156 results on '"BIOFILMES"'
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2. Urinary catheter: can exposure time and gauge affect biofilm formation?
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Amorim Batista, Odinéa Maria, Maciel Monteiro, Rachel, Buzanelo Machado, Marinila, Menis Ferreira, Adriano, Moura da Costa Valle, Andreia Rodrigues, Watanabe, Evandro, de Araújo Madeiro, Maria Zélia, and Batista Moura, Maria Eliete
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URINE microbiology ,BIOFILMS ,CELL culture ,ELECTRON microscopy ,NEEDLE biopsy ,PSEUDOMONAS diseases ,STAPHYLOCOCCUS aureus ,TREATMENT duration ,URINARY catheters ,DATA analysis software ,DESCRIPTIVE statistics ,CATHETER-related infections ,IN vitro studies - Abstract
Copyright of Acta Paulista de Enfermagem is the property of Universidade Federal de Sao Paulo, Escola Paulista de Enfermagem and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2018
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3. Biofilm formation and antibiotic susceptibility of Staphylococcus and Bacillus species isolated from human allogeneic skin
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Micaela do Canto Canabarro, Gertrudes Corção, Mercedes Passos Geimba, and Karine Lena Meneghetti
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Clinical Microbiology - Research Paper ,Multidrug tolerance ,Resazurin ,Tetracycline ,medicine.drug_class ,Staphylococcus ,Antibiotics ,Bacillus ,Microbial Sensitivity Tests ,medicine.disease_cause ,Microbiology ,Minimum inhibitory concentration ,Media Technology ,medicine ,Humans ,Antibiotic tolerance ,Skin banks ,Allograft contamination ,biology ,Chemistry ,Hematopoietic Stem Cell Transplantation ,Biofilm ,Aloenxertos ,biology.organism_classification ,Anti-Bacterial Agents ,Antibacterianos ,Biofilms ,Gentamicin ,Biofilmes ,Bacteria ,medicine.drug - Abstract
Human skin banks around the world face a serious problem with the high number of allogeneic skins that are discarded and cannot be used for grafting due to persistent bacterial contamination even after antibiotic treatment. The biofilm formation capacity of these microorganisms may contribute to the antibiotic tolerance; however, this is not yet widely discussed in the literature. Thisstudy analyzed bacterial strains isolated from allogeneic human skin samples,which were obtained from a hospital skin bank that had already been discardeddue to microbial contamination. Biofilm formation and susceptibility topenicillin, tetracycline, and gentamicin were evaluated by crystal violetbiomass quantification and determination of the minimum inhibitoryconcentration (MIC), minimum biofilm inhibitory concentration (MBIC), andminimum biofilm eradication concentration (MBEC) by the broth microdilutionmethod with resazurin dye. A total of 216 bacterial strains were evaluated, and204 (94.45%) of them were classified as biofilm formers with varying degrees ofadhesion. MBICs were at least 512 times higher than MICs, and MBECs were atleast 512 times higher than MBICs. Thus, the presence of biofilm in allogeneicskin likely contributes to the inefficiency of the applied treatments as antibiotictolerance is known to be much higher when bacteria are in the biofilmconformation. Thus, antibiotic treatment protocols in skin banks shouldconsider biofilm formation and should include compounds with antibiofilmaction.
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- 2021
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4. Lesiones endodónticas persistentes
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Biagio, Bianca, Silveira, Cláudia Fernandes de Magalhães, Lopes, Gabriela, Berger, Sandrine Bittencourt, Gregorio, Danielle, Pizzurno, Lucia Gloria Diana Aguilar, Carvalho-Ferreira, Terezinha de Jesus, Pellizzaro, Delise, and Guiraldo, Ricardo Danil
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Biofilm ,Candida albicans ,Periodontite periapical ,Biofilmes ,Periodontitis apical ,Periapical periodontitis - Abstract
Apical periodontitis is mainly caused by both microrganisms and their virulence factors. This process can be associated with the survival of its causative agents due to coronary microleakage after chemical-mechanical preparation and filling. However, persistent apical periodontitis can be solved through endodontic retreatment or apical surgery. In addition, its association with systemic diseases has been reported in different studies. The aim of the current study is to perform a literature review on studies about apical periodontitis, with emphasis on current microbial profile and treatment modalities. Studies have shown significant heterogeneity in microbial profile, as well as likely associations with some diseases. Moreover, they have mainly focused on investigating persistent apical periodontitis based on molecular biology. It was possible concluding that, although Enterococcus faecalis is the species most often associated with failure in endodontic treatments, the incidence of other microrganisms, such as Candida albicans, Streptococcus spp., Actinobacteria spp., has been observed at the same, or even at higher, level than that of E. faecalis. Retreatment should always be taken into consideration as the first option to treat morbidities, although surgery can be performed if retreatment is not successful. La periodontitis apical es causada principalmente por microorganismos y sus factores de virulencia. Este proceso puede ocurrir a través de la supervivencia de los agentes causales debido a la microinfiltración coronaria luego de la preparación químico-mecánica y la obturación. Sin embargo, la periodontitis apical persistente puede ser solucionada a través del retratamiento endodóntico o la cirugía apical. Este trabajo tuvo como objetivo realizar una revisión de literatura sobre la periodontitis apical destacando el perfil microbiano actual y modalidades de tratamiento. Las investigaciones han demostrado gran diversidad en lo que respecta al perfil microbiano, así como posibles asociaciones con algunas enfermedades sistémicas. Además, los estudios han dado gran enfoque a la periodontitis apical persistente a nivel molecular. Pudimos concluir que a pesar del Enterococcus faecalis ser la especie más comúnmente asociada a la falla del tratamiento endodóntico, se ha observado la presencia de otros tipos de microorganismos, como: Candida albicans, Streptococcus spp., Actinobacteria spp. En relación con las modalidades de tratamiento, el retratamiento debe ser considerado como primera opción y en caso de fracaso, la cirugía puede ser realizada. A periodontite apical é causada principalmente por microrganismos e seus fatores de virulência. Esse processo pode estar associado à sobrevivência de seus agentes causadores devido à microinfiltração coronariana após preparo químico-mecânico e preenchimento. No entanto, a periodontite apical persistente pode ser resolvida através de retratamento endodôntico ou cirurgia apical. Além disso, sua associação com doenças sistêmicas tem sido relatada em diferentes estudos. O objetivo do presente estudo é realizar uma revisão de literatura sobre periodontite apical, com ênfase no perfil microbiano atual e modalidades de tratamento. Estudos têm demonstrado significativa heterogeneidade no perfil microbiano, bem como prováveis associações com algumas doenças. Além disso, eles se concentraram principalmente na investigação da periodontite apical persistente com base na biologia molecular. Foi possível concluir que, embora Enterococcus faecalis seja a espécie mais frequentemente associada ao insucesso em tratamentos endodônticos, a incidência de outros microrganismos, como Candida albicans, Streptococcus spp., Actinobacteria spp. nível superior ao de E. faecalis. O retratamento deve sempre ser considerado como a primeira opção para tratar as morbidades, embora a cirurgia possa ser realizada se o retratamento não for bem sucedido.
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- 2022
5. Estudio de la tecnología de plasma frío utilizando el software VOSviewer
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Brito , Amanda Cândido, Silva , Lucas Donizete da, Vianna , Priscila Cristina Bizam, Paiva , Aline Dias, Gonçalves , Letícia Dias dos Anjos, and Naves, Emiliane Andrade Araújo
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Enfermedades transmitidas por los alimentos ,Biofilm ,Plasma frio atmosférico ,Alimentación ,Bacterial adhesion ,Adhesión bacteriana ,Seguridad microbiológica ,Atmospheric cold plasma ,Plasma frío atmosférico ,Adesão bacteriana ,Microbiological safety ,Alimentos ,Food ,Foodborne diseases ,Biofilms ,Doenças transmitidas por alimentos ,Segurança microbiológica ,Biofilmes - Abstract
One of the biggest challenges for food industry is to offer microbiologically safe and nutritious products to consumers. Foodborne diseases are considered a recurring public health problem, in addition to causing economic impacts for industries. Pathogenic bacteria can be introduced into foods during several steps along the production chain. In this context, microbial biofilms stand out as sources of contamination of food and processing surfaces. These biofilms form communities resistant to conventional chemical sanitizers. Thus, the demand for new alternatives for surface decontamination is evident, giving rise to interest in the application of cold plasma. This review aimed a systematic work of the literature on the use of cold plasma, using the Science Direct database, with the keywords cold plasma and biofilms. The selected articles were analyzed in Vosviewer software. After interpreting density maps, it was noticed that the most published topics related to cold plasma were food safety, food preservation and plasma. It was found that the cold plasma is a new approach, for which promising results have been observed for the microbiological safety of foods, being a viable alternative for decontamination of surfaces and foods, as well as for the reduction of microbial adhesion and formation of biofilms on food and processing surfaces. However, further studies are needed for validation and industrial commercialization and on its effects on sensory characteristics of foods subjected to this treatment. Uno de los mayores desafíos para la industria alimentaria es ofrecer productos microbiológicamente seguros y nutritivos a los consumidores. Las enfermedades transmitidas por alimentos son consideradas un problema de salud pública recurrente, además de causar impactos económicos para las industrias. Las bacterias patógenas pueden introducirse en los alimentos durante varios pasos a lo largo de la cadena de producción. En este contexto, las biopelículas microbianas se destacan como fuentes de contaminación de alimentos y superficies de procesamiento. Estas biopelículas forman comunidades resistentes a los desinfectantes químicos convencionales. Así, se hace evidente la demanda de nuevas alternativas para la descontaminación de superficies, despertando el interés por la aplicación del plasma frío. Esta revisión tuvo como objetivo un estudio sistemático de la literatura sobre el uso de plasma frío, utilizando la base de datos Science Direct, con las palabras clave cold plasma y biofilms. Los artículos seleccionados fueron enviados para su análisis en el software Vosviewer. Después de interpretar los mapas de densidad obtenidos, se observó que los temas más estudiados relacionados con el plasma frío fueron la seguridad alimentaria, la conservación de alimentos y el plasma. Se encontró que la tecnología de plasma frío es un nuevo enfoque, para el cual se han observado resultados promisorios para la seguridad microbiológica de los alimentos, siendo una alternativa viable para la descontaminación de superficies y alimentos, así como para la reducción de la adhesión microbiana y formación de biopelículas en alimentos y superficies de procesamiento. Sin embargo, se necesitan más estudios para su validación y comercialización industrial y sobre sus efectos en las características sensoriales de los alimentos sometidos a este tratamiento. Um dos maiores desafios das indústrias de alimentos é oferecer produtos seguros do ponto de vista microbiológico e nutritivos aos consumidores. As doenças transmitidas por alimentos são consideradas um problema recorrente à saúde pública, além de causarem impactos econômicos para as indústrias. Bactérias patogênicas podem ser introduzidas nos alimentos durante várias etapas, ao longo da cadeia de produção. Nesse contexto, destacam-se os biofilmes microbianos como fontes de contaminação de alimentos e de superfícies processadoras. Estes biofilmes formam comunidades resistentes aos sanitizantes químicos convencionais. Assim, fica evidente a demanda por novas alternativas para descontaminação de superfícies, surgindo o interesse pela aplicação do plasma frio. Esta revisão objetivou um estudo sistemático da literatura sobre o uso do plasma frio, utilizando a base de dados da Science Direct, com as palavras-chave cold plasma e biofilms. Os artigos selecionados foram submetidos para análise no software Vosviewer. Após interpretação dos mapas de densidade obtidos percebeu-se que os temas mais estudados relacionados ao plasma frio foram segurança de alimentos, preservação de alimentos e plasma. Constatou-se que a tecnologia de plasma frio é uma abordagem nova, para a qual tem sido observado resultados promissores para a segurança microbiológica dos alimentos, sendo uma alternativa viável para descontaminação de superfícies e de alimentos, assim como para a redução da adesão microbiana e formação de biofilmes em alimentos e superfícies de processamento. Entretanto, são necessários estudos complementares para validação e comercialização industrial e sobre seus efeitos sobre as características sensoriais dos alimentos submetidos a esse tratamento.
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- 2022
6. Population pharmacokinetic modeling of tobramycin in preclinical acute and chronic lung infection by mucoid and non-mucoid biofilm-forming Pseudomonas aeruginosa
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Dias, Bruna Bernar, Dalla Costa, Teresa Cristina Tavares, and Carreño, Fernando Olinto
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Biofilm ,Microdialysis ,Tobramicina ,Pseudomonas aeruginosa ,Tobramycin ,Farmácia ,Pneumonia ,Lung infection ,PopPK model ,Biofilmes - Abstract
Introdução: Infecções pulmonares por bactérias formadoras de biofilmes são um desafio na prática clínica, devido à tolerância aos antimicrobianos que reduz as concentrações livres na biofase dificultando o sucesso terapêutico. Ao mesmo tempo, os processos infeciosos causam alterações fisiológicas que podem alterar a distribuição de antimicrobianos no sítio de ação. Em trabalhos prévios do grupo de pesquisa investigou-se a penetração pulmonar e no líquido de revestimento pulmonar (ELF) da tobramicina (TOB) utilizando microdiálise em modelo animal de infecção aguda e crônica por Pseudomonas aeruginosa formadora de biofilme. Observou-se que as concentrações livres plasmáticas e livres pulmonares da TOB são semelhantes em animais hígidos, porém as concentrações brônquicas são 90% menores. Nos animais com infecção aguda (7 d) com cepa não-mucoide observou-se uma redução na penetração pulmonar e no ELF em torno de 70%. Nos animais com infecção crônica (14 d) com cepa mucoide observou-se concentrações plasmáticas e pulmonares reduzidas, com aumento do clearance plasmático do fármaco. Objetivo: O objetivo deste trabalho foi desenvolver modelo farmacocinético populacional (popPK) para descrever as concentrações plasmáticas totais e livres pulmonares e no ELF da TOB em infecções agudas e crônicas causadas por P. aeruginosa e utilizar o modelo desenvolvido para avaliar a probabilidade de atingir o alvo terapêutico (PTA) de diferentes regimes posológicos. Metodologia: O modelo popPK foi desenvolvido no software NONMEM 7.4 (Icon®). Usando o modelo, simulações de concentrações livres no pulmão e no ELF de diferentes regimes posológicos recomendados na clínica foram feitas e a PTA do índice PK/PD concentração máxima livre/concentração inibitória mínima (ƒCmáx/CIM) > 10 foi investigado utilizando os dados de CIM de P. aeruginosa do EUCAST. Uma PTA > 90 % foi considerada como desfecho clínico favorável. Resultados: O modelo popPK com três compartimentos, incluindo o pulmão, foi capaz de descrever todos os cenários investigados. As concentrações de TOB no ELF foram menores do que as concentrações pulmonares e, em todos os grupos, foram descritas por um fator de distribuição derivado do compartimento pulmonar. A infecção foi uma covariável no volume do pulmão (V3) e apenas a infecção crônica foi incluída como covariável no volume do compartimento central (V1) e no clearance total (CL). As simulações demonstraram que a dose única diária tem maior PTA no pulmão do que a dose fracionada três vezes ao dia. Nenhuma posologia investigada pela via intravenosa gerou concentrações no ELF adequadas para erradicação bacteriana. Os tratamentos recomendados, que geram concentrações pulmonares adequadas para tratar pneumonias agudas e crônicas por P. aeruginosa formadora de biofilme (PTA > 90%) foram TOB 4,5 mg/kg q24h e 11 mg/kg q24h, respectivamente. Conclusões: O modelo foi capaz de descrever a redução nas concentrações pulmonares nos animais infectados e a proporcionalidade entre concentrações livres no pulmão e ELF nas condições hígido e infectados. Os resultados do PTA indicam a necessidade de investigar na clínica posologias alternativas para uso da TOB no tratamento de pneumonias. Introduction: Biofilm-forming lung infections are a challenge in clinical practice due to tolerance to antimicrobials that reduces free concentrations at the biophase, making therapeutic success difficult. At the same time, infectious cause physiological changes that can alter antimicrobial’s distribution at the site of action. In previous work our research group have been studying tobramycin (TOB) lung and epithelial lining fluid (ELF) penetration in animal models of acute and chronic lung infection by biofilm-forming P. aeruginosa. It was observed that TOB free plasma and free lung concentrations are similar in healthy animals, however free ELF concentrations are 90% lower. In animals with acute infection (7 days) with non-mucoid biofilm-forming P. aeruginosa, there was a reduction in TOB lung and ELF penetration around 70%. In animals with chronic infection (14 days) with mucoid biofilm-forming P. aeruginosa, reduced TOB free plasma and free lung concentrations were observed, with increased plasma clearance of the drug. Objective: The aim of this work was to develop a population pharmacokinetic (popPK) model to describe TOB total plasma, free lung and free ELF concentrations in acute and chronic P. aeruginosa lung infection, and use this model to evaluate the probability of target attainment (PTA) of different therapeutic regimes. Methods: The popPK model was developed in NONMEM 7.4 (Icon®). Using the developed model, simulations of free lung and ELF concentrations in different therapeutic regimes recommended in clinical practice were performed and the PTA of the PK/PD index maximum free concentration/minimum inhibitory concentrations (ƒCmax/CIM) > 10 was investigated using the EUCAST database for P. aeruginosa MIC. A PTA > 90% was assumed as adequate clinical outcomes. Results: The popPK model with three compartments including the lung was able to describe all the investigated scenarios. The ELF concentrations were lower than the lung concentrations, and for all groups they were explained by a penetration factor derived from lung compartment. Infection was a covariate in the volume of the lung compartment (V3) and only the chronic infection was included as covariate for the central compartment (V1) and total clearance (CL). Simulations demonstrated that once daily dose has higher PTA in the lung than the same dose divided three times a day. None of the intravenous dosages investigated was able to achieve enough concentrations in ELF to bacterial eradication. The recommended treatments, which produced adequate lung free concentrations to treat acute and chronic pneumonia by biofilm-forming P. aeruginosa (PTA > 90%) were TOB 4.5 mg/kg q24h and 11 mg/kg q24h, respectively. Conclusions: The model was able to describe the reduction in TOB lung concentrations in the infected animals and the proportionality between free lung and ELF concentrations in healthy and infected conditions. The PTA results indicate the need to investigate alternative TOB posologies to treat pneumonia in the clinic.
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- 2022
7. Influence of milk proteins on the adhesion and formation of Bacillus sporothermodurans biofilms : implications for dairy industrial processing
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Vanessa Pereira Perez Alonso, Dirce Yorika Kabuki, Mônica A. Cotta, Rodrigo Cezar de Campos Ferreira, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Sanitizer ,Casein ,Dairy industry ,Soro do leite ,Microscopia ,Plate count ,Whey ,Bacillus sporothermodurans ,Artigo original ,Food science ,Microscopy ,biology ,Chemistry ,fungi ,Biofilm dispersal ,Biofilm ,Adhesion ,biology.organism_classification ,Spore ,Biofilms ,Biofilm life cycle ,Biofilm architecture ,Total bacterial count ,Biofilmes ,Caseina ,Food Science ,Biotechnology - Abstract
Agradecimentos: This work was supported by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, Brazil) - Finance Code 001. The authors acknowledge financial support from IFGW - UNICAMP, for granting equipment access at the Multiuser Laboratory (LAMULT). The authors thank Prof. Dr. Richard Landers (IFGW, UNICAMP) for XPS analyses and Laboratório Multiusuário (LAMULT - IFGW) for SEM analyses. We also thank Dr. Darla Goeres for the kind assistance with the methodology (Single Tube Method). The authors also are grateful to Dr. Meg da S. Fernandes. We also acknowledge the following companies for providing the consumables used in this work: CCQA/ITAL collection (DSMZ 10599), ECOLAB Brazil (stainless steel surfaces and sanitizers), iTram Higiene, Spain (enzymatic products), Alibra Brazil (casein), and Arla Foods (whey) Abstract: Bacillus sporothermodurans is a producer of highly heat-resistant spores, which is a problem for the dairy industry worldwide. In this work, we studied the attachment and biofilm formation on stainless steel surfaces in contact with milk proteins (casein and whey). The results of the biofilm formation were obtained by the plate count method. In conjunction, biofilms (niches and cell sizes) were measured by scanning electron microscopy (SEM) on the 1st, 5th and 10th day. X-ray photoelectron spectroscopy (XPS) was a complementary technique that probed the conditioning of the substrate surface after 24 h. The milk proteins affected the total bacterial count in the samples, and also influenced the biofilm architecture. Sessile cell counts varied from 4.3 log CFU/cm2 in the attachment stage to up to 10.2 log CFU/cm2 in the matured biofilm stage. The spore counts varied from
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- 2022
8. Isolamento e identificação de amebas de vida livre potencialmente patogênicas em amostras de ambientes de hospital público da cidade de Porto Alegre, RS Isolation and identification of potentially pathogenic free-living amoebae in samples from environments in a public hospital in the city of Porto Alegre, Rio Grande do Sul
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Ana Maris Carlesso, Amauri Braga Simonetti, Geórgia Lazzari Artuso, and Marilise Brittes Rott
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Amebas de vida livre ,Poeira ,Biofilmes ,Ambiente hospitalar ,Acanthamoeba ,Free-living amoebae ,Dust ,Biofilm ,Hospital environment ,Arctic medicine. Tropical medicine ,RC955-962 - Abstract
Um estudo sobre a presença de amebas de vida livre em um hospital público foi desenvolvido na Cidade de Porto Alegre, RS. Poeira e biofilmes de 15 ambientes hospitalares, incluindo CTI, UTI pediátrica, cozinha, emergência, centro cirúrgico ambulatorial e centro cirúrgico, reservatórios de água, torneira e 6 bebedouros coletivos foram coletados mensalmente, de julho de 2004 a março de 2005, usando-se suabes estéreis, preparados para a pesquisa. As AVL foram isoladas em cultivo, utilizando-se meio de ágar não nutriente adicionado de Escherichia coli, mortas pelo calor. A identificação dos protozoários foi feita pela observação morfológica de cistos e trofozoítos, segundo critérios morfológicos de Page (1988). Das 135 amostras coletadas dos 15 ambientes estudados, 47 (35%) foram positivas para AVL. Destas, 34% apresentaram características morfológicas próprias do gênero Acanthamoeba.A study on the presence of free-living amoebae in a public hospital was developed in the city of Porto Alegre, State of Rio Grande do Sul. Dust and biofilms were collected using sterile swabs that had been prepared for this study, from 15 hospital environments, including the intensive care center, pediatric intensive care unit, kitchen, emergency room, outpatient surgical center, clinical surgical center, water storage tanks, taps and six drinking fountains for general use, every month from July 2004 to March 2005. The FLAs were isolated by culturing, using non-nutrient agar medium with the addition of heat-killed Escherichia coli. The protozoa were identified by morphological observation of cysts and trophozoites, in accordance with Page's morphological criteria (1988). Among the 135 samples collected from the 15 environments, 47 (35%) were positive for FLAs. Of these, thirty-four percent presented morphological characteristics particular to the genus Acanthamoeba.
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- 2007
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9. Mycobacterium tuberculosis and Paracoccidioides brasiliensis Formation and Treatment of Mixed Biofilm In Vitro
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Caroline Maria Marcos, Marcelo A. Pereira-da-Silva, Kaila P. Medina-Alarcón, Mariana Bastos dos Santos, Maria José Soares Mendes-Giannini, Giovana Garcia Ferin, Fernando Rogério Pavan, Iara Pengo Tobias da Silva, Ana Marisa Fusco-Almeida, Marlus Chorilli, Luis Octávio Regasini, Universidade Estadual Paulista (UNESP), Universidade de São Paulo (USP), and Paulista Central University Center (UNICEP)
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Microbiology (medical) ,3’hydroxychalcone ,Bacilli ,Tuberculosis ,BIOFILMES ,Immunology ,nanoemulsion ,Microbiology ,Mycobacterium tuberculosis ,Minimum inhibitory concentration ,Cellular and Infection Microbiology ,medicine ,Original Research ,Paracoccidioides brasiliensis ,biology ,Chemistry ,Biofilm ,biology.organism_classification ,medicine.disease ,QR1-502 ,In vitro ,mixed biofilm ,Infectious Diseases ,Antibacterial activity - Abstract
Made available in DSpace on 2022-04-29T08:36:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-11-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Co-infection of Mycobacterium tuberculosis and Paracoccidioides brasiliensis, present in 20% in Latin America, is a public health problem due to a lack of adequate diagnosis. These microorganisms are capable of forming biofilms, mainly in immunocompromised patients, which can lead to death due to the lack of effective treatment for both diseases. The present research aims to show for the first time the formation of mixed biofilms of M. tuberculosis and P. brasiliensis (Pb18) in vitro, as well as to evaluate the action of 3’hydroxychalcone (3’chalc) -loaded nanoemulsion (NE) (NE3’chalc) against monospecies and mixed biofilms, the formation of mixed biofilms of M. tuberculosis H37Rv (ATCC 27294), 40Rv (clinical strains) and P. brasiliensis (Pb18) (ATCC 32069), and the first condition of formation (H37Rv +Pb18) and (40Rv + Pb18) and second condition of formation (Pb18 + H37Rv) with 45 days of total formation time under both conditions. The results of mixed biofilms (H37Rv + Pb18) and (40Rv + Pb18), showed an organized network of M. tuberculosis bacilli in which P. brasiliensis yeasts are connected with a highly extracellular polysaccharide matrix. The (Pb18 + H37Rv) showed a dense biofilm with an apparent predominance of P. brasiliensis and fragments of M. tuberculosis. PCR assays confirmed the presence of the microorganisms involved in this formation. The characterization of NE and NE3’chalc displayed sizes from 145.00 ± 1.05 and 151.25 ± 0.60, a polydispersity index (PDI) from 0.20± 0.01 to 0.16± 0.01, and zeta potential -58.20 ± 0.92 mV and -56.10 ± 0.71 mV, respectively. The atomic force microscopy (AFM) results showed lamellar structures characteristic of NE. The minimum inhibitory concentration (MIC) values of 3’hidroxychalcone (3’chalc) range from 0.97- 7.8 µg/mL and NE3’chalc from 0.24 - 3.9 µg/mL improved the antibacterial activity when compared with 3’chalc-free, no cytotoxicity. Antibiofilm assays proved the efficacy of 3’chalc-free incorporation in NE. These findings contribute to a greater understanding of the formation of M. tuberculosis and P. brasiliensis in the mixed biofilm. In addition, the findings present a new possible NE3’chalc treatment alternative for the mixed biofilms of these microorganisms, with a high degree of relevance due to the lack of other treatments for these comorbidities. School of Pharmaceutical Sciences Department of Clinical Analysis Universidade Estadual Paulista (UNESP) Institute of Physics of Sao Carlos (IFSC) University of Sao Paulo (USP) IFSC/USP Exact Sciences and Engineering Paulista Central University Center (UNICEP) Department of Chemistry and Environmental Sciences Institute of Biosciences Humanities and Exact Sciences Universidade Estadual Paulista Department of Drug and Medicines School of Pharmaceutical Sciences Universidade Estadual Paulista Department of Biological School of Pharmaceutical Sciences Universidade Estadual Paulista School of Pharmaceutical Sciences Department of Clinical Analysis Universidade Estadual Paulista (UNESP) Department of Chemistry and Environmental Sciences Institute of Biosciences Humanities and Exact Sciences Universidade Estadual Paulista Department of Drug and Medicines School of Pharmaceutical Sciences Universidade Estadual Paulista Department of Biological School of Pharmaceutical Sciences Universidade Estadual Paulista
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- 2021
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10. Clinical, microbiological, and immunological evaluation of patients in corrective orthodontic treatment
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Magda Feres, Mariana Umekita Shirozaki, Marília Pacífico Lucisano, Michel Reis Messora, Arthur Belém Novaes Júnior, Andiara De Rossi, Raquel Assed Bezerra da Silva, Léa Assed Bezerra da Silva, and Fábio Lourenço Romano
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0301 basic medicine ,BIOFILMES ,Bleeding on probing ,Dentistry ,Orthodontics ,Orthodontics, Corrective ,03 medical and health sciences ,Gingivitis ,0302 clinical medicine ,Statistical significance ,Humans ,Medicine ,In patient ,Periodontology ,Tumor Necrosis Factor-alpha ,business.industry ,Research ,Biofilm ,Dental Plaque Index ,Significant difference ,Gingival Crevicular Fluid ,030206 dentistry ,Red complex ,lcsh:RK1-715 ,030104 developmental biology ,lcsh:Dentistry ,Analysis of variance ,Periodontal Index ,medicine.symptom ,business - Abstract
Background The objective was to analyze clinical, microbiological, and immunological periodontal parameters in patients in corrective orthodontic treatment. Materials and methods Twenty-eight patients were selected. Plaque index (PI), bleeding on probing (BOP), width of keratinized gingiva, levels of 40 bacterial species, and of 3 cytokines (IL-1β, MMP-8, and TNF-α) in gingival crevicular fluid (GCF) were evaluated at T0, before orthodontic treatment; T1, 6 months; and T2, 12 months post-treatment. Non-parametric, Friedman, Wilcoxon, ANOVA, and Spearman correlation coefficient tests were used for statistical analyses, with the significance level of 5%. Results No significant difference was found for the width of keratinized gingiva, but PI presented a significant increase at T1 and T2 (p p p > 0.05). In the microbiological analysis, red complex pathogens were in significantly greater proportions in T2 compared with T0 (p r = 0.49 p = .01) and TNF-α (r = 0.39 and p = .05). Conclusion In conclusion, corrective orthodontic treatment caused clinical periodontal alterations regarding biofilm accumulation and gingival bleeding, with alteration of periodontopathogens.
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- 2020
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11. Desenvolvimento de filmes biodegradaveis a partir de derivados do grão de quinoa (Chenopodium quinoia Willdenow) da variedade 'Real'
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Araujo Farro, Patricia Cecilia, Menegalli, Florência Cecília, 1944-2017, Sobral, Paulo José do Amaral, Freire, Maria Teresa de Alvarenga, Cunha, Rosiane Lopes da, Laurindo, João Borges, Yamashita, Fabio, Grosso, Carlos Raimundo Ferreira, Universidade Estadual de Campinas. Faculdade de Engenharia de Alimentos, Programa de Pós-Graduação em Engenharia de Alimentos, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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X-ray ,Farinhas ,Quinoa ,Biofilm ,Flours ,ATR-FTIR spectroscopy ,Starch ,Extraction ,Amido ,Extração ,ATR-FTIR espectroscopia ,Biofilmes ,Raios X - Abstract
Orientadores: Florencia Cecilia Menegalli, Paulo Jose do Amaral Sobral Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Resumo: O grão de quinoa (Chenopodium quinoa, Willdenow) é um pseudocereal originário da América do Sul Andina, que tem gerado interesse industrial crescente e cultivo diversificado em diversos países de América do Norte e da Europa. Recentemente nos países da América Latina tem-se despertado um interesse comum na busca de tecnologias de desenvolvimento de biomateriais, como uma forma de diminuir a poluição gerada pelos resíduos sintéticos, utilizando os recursos naturais próprios da região. O Brasil destaca-se pela sua preocupação pelo meio ambiente e manutenção das fontes destes recursos, através de programas experimentais de adaptação de culturas, como a quinoa, nos cerrados brasileiros, com resultados satisfatórios. O uso potencial da quinoa na indústria alimentícia tem sido alvo de estudos diversos. No entanto, é pouco explorada a aplicabilidade de produtos derivados deste grão, como farinhas e amido, na área de biomateriais. Dentro desse contexto, os principais objetivos deste trabalho foram: (1) desenvolver tecnologias pouco agressivas de extração de matérias-primas a partir do grão de quinoa: farinha integral (FI); farinha por extração úmida (FU) e amido (AQ); (2) caracterização das propriedades físico-químicas e estruturais destes produtos; (3) análises reológicas de soluções formadoras de filmes a partir do amido; (4) avaliação de diferentes formulações utilizadas na elaboração de filmes utilizando um planejamento fatorial completo analisando os efeitos de concentração de glicerol, do pH da solução filmogênica, e das condições de secagem (T(ºC) / t (horas)) em função da solubilidade e das propriedades mecânicas dos filmes; (5) otimização do processo de elaboração de filmes e caracterização dos filmes ótimos quanto às propriedades termomecânicas, óticas e estruturais, e cristalinidade (FTIR e Raios X). Os filmes elaborados a partir das diferentes matérias-primas obtidas do grão de quinoa foram elaborados utilizando 4% de matéria prima/ 100 g de solução filmogênica. Esta porcentagem da matéria prima foi determinada através das análises reológicas. Foi utilizado um planejamento fatorial completo 23, onde as três variáveis independentes foram: concentração de glicerol (16,6; 20; 25; 30 e 33,4 g/100 g matéria-prima), nível de pH de soluções filmogênica (9,7; 10; 10,5; 11 e 11,3) e condições de secagem (30°C/20h; 34°C/17h; 40°C/10h; 46°C/9h e 50°C/5h). As variáveis respostas foram: teste mecânico de tração (força na tração e elongação no ponto de ruptura); teste mecânico de perfuração (força na perfuração e deformação na perfuração) e solubilidade em água a 25ºC. Uma vez determinadas as equações dos modelos matemáticos, foi aplicada a função desejabilidade para estabelecer as condições ótimas de elaboração de filmes. Para o filme de amido de quinoa, a condição ótima foi obtida com concentração de glicerol de 21,2%, pH de 10,7 e condição de secagem de 36ºC/14h. Para o filme de FU: Concentração de glicerol de 21%, nível de pH de 10,48 e condição de secagem de 42ºC/8h. E para o filme de FI foi de concentração de glicerol de 20%, nível de pH de 10,6 e condição de secagem de 38ºC/12h. Os filmes de amido de quinoa mostraram-se incolores e pouco opacos, apresentando reduzida solubilidade em água e boa resistência à tração e flexibilidade. Os filmes de farinha por extração úmida apresentaram leve cor amarela, moderada opacidade e flexibilidade. Já os filmes de farinha integral apresentaram cor amarela intensa, moderada opacidade, alta flexibilidade mas baixa resistência no teste de tração Abstract: Quinoa (Chenopodium quinoa, Willdenow) is a native and oldest pseudocereal grain from the Andean region in South America. Nowadays, due to an increasing industrial interest, quinoa seeds are grown in different countries as in North America and Europe. Recently, Latin American countries have shared a common interest regarding the use of natural resources in technologies capable of minimizing pollution. In that sense, special attention has been given towards the development of new biomaterials that could diminish synthetic residues. In the last years, Brazil participated in experimental programs of culture adaptation, with satisfactory results for quinoa crops. In spite of the great amount of studies concerning the potential use of quinoa in the food industry, the use of the quinoa seeds as source of starch and flour and their applicability in the biomaterials development field has not yet been fully explored. The aims of this work were: (1) to develop a non aggressive raw material (starch and flours) extraction technique, (2) determine the structural and physical-chemical properties of the quinoa products (3) characterization of the film-forming solutions through rheological analyses (4) to evaluate the effects of the glycerol content, pH and drying conditions of film-forming solutions on some functional properties of its edible films using an experimental design (response surface methodology). The responses were mechanical properties as puncture strength, puncture deformation, tensile strength, elongation and Young modulus and solubility, (5) optimization of the films elaborative process and characterization (thermomechanical, optical and structural properties, and crystallinity - FTIR and X-ray) of the optimal quinoa films. According to an experimental design 23, films were produced from film forming solutions (FFS) containing 4g of Quinoa products (QP) /100g of FFS (this percentage of QP was determined by rheological tests), glycerol (16.6, 20.0, 25.0, 30.0 and 33.4 g/100 g starch) used as a plasticizer, and a constant pH of FFS (9.7, 10.0, 10.5, 11.0 and 11.3). Drying conditions varied from temperature and time (30°C/20h; 34°C/17h; 40°C/10h; 46°C/9h and 50°C/5h) in an oven with circulation and renewal of air. The five levels of each variable were coded as -1.68, - 1, 0, +1, +1.68. All tests were run at room conditions (22-25ºC and 55-65% relative humidity) using samples previously conditioned at 58% of relative humidity at 22-25ºC for 7 days. The optimal films elaboration conditions were determined by the desirability function. For each quinoa product, conditions were different. For films based on starch (S), the optimal condition was obtained when using 21,2% glycerol content, pH= 10,7 and drying condition of 36ºC/14h, for films of flour extracted by wet milling (FWM), 21% glycerol content, pH= 10,48 and drying condition of 42ºC/8h, and, finally, for films of whole flour (WF), 20% glycerol content, pH= 10,6 and drying condition of 38ºC/12h The S films were colorless and scarcely opaque, showed reduced water solubility, and presented good qualities of tensile strength. FWM films presented a yellowish color, moderate opacity, tensile strength and flexibility. WF films presented an intense yellowish color, moderate opacity and high flexibility but low tensile strength Doutorado Doutor em Engenharia de Alimentos
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- 2021
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12. Analise funcional e estrutural da proteina BigR de Xylella fastidiosa envolvida na regulação do operon Xf0768-0764
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Barbosa, Rosicler Lazaro, 1978, Benedetti, Celso Eduardo, 1964, Marques, Marilis do Valle, Nunes, Luiz Roberto, Souza, Anete Pereira de, Souza, Alessandra Alves de, Universidade Estadual de Campinas. Instituto de Biologia, Programa de Pós-Graduação em Genética e Biologia Molecular, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Xylella fastidiosa ,Regulação da expressão gênica ,Gene expression regulation ,BigR protein ,Fatores de transcrição ,Biofilm ,Transcriptional factor ,Proteina bigR ,Biofilmes - Abstract
Orientador: Celso Eduardo Benedetti Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia Resumo: O gene XF0767 de Xylella fastidiosa está localizado num operon composto por mais quatro genes classificados como proteínas hipotéticas (XF0768-XF0767-XF0766-XF0765-XF0764). Este operon está conservado em uma série de bactérias associadas a plantas, incluindo Agrobacterium tumefaciens, Mezorhizobium loti e Sinorhizobium meliloti. A região upstream ao códon de iniciação deste operon possui seqüências canônicas correspondentes a sítios -35 e ¿10 de regiões promotoras reguladas por fatores sigma70. O objetivo deste trabalho foi caracterizar o sistema de regulação do operon pela proteína XF0767, nomeada BigR (biofilm growth-associated repressor), visando à compreensão deste sistema e sua importância para a bactéria. A proteína BigR se liga na seqüência repetida invertida (9-4-9) localizada na região ¿10 do promotor do operon XF0768-0764, denominada BigRbox. BigR inibe a atividade do operon reprimindo a expressão do gene repórter GFP em Escherichia coli, Agrobacterium tumefaciens e Xylella fastidiosa. Mutações no BigRbox dos promotores de Xylella e Agrobacterium afetam a ligação do repressor e abole a transcrição do gene repórter. Esses dados indicam, portanto, que BigR compete com a RNA polimerase pelo mesmo sítio de ligação ao DNA, revelando assim o mecanismo de regulação do operon. BigR apresenta similaridade com fatores transcricionais de bactérias contendo domínio HTH (helix-turn-helix) de ligação ao DNA. Apesar de BigR ter sido inicialmente classificada como uma proteína da família SmtB/ArsR, as quais regulam operons relacionados à resistência a metais, nossos dados indicam que BigR não atua como sensor de metal. A adição de cádmio, ferro e cobre na mistura de ligação causam uma aparente dissociação do complexo DNA/BigR, entretanto, estudos in vivo na presença de metais não evidenciaram nenhuma alteração na expressão do gene repórter. Mutantes deficientes em BigR também não apresentam diferença de crescimento na presença de metais. O gene XF0768 codifica uma proteína nomeada BLH (beta-lactamase-like hydrolase) por pertencer à superfamília das metalo-beta-lactamases. Dada a presença de BigR e BLH no operon de Xylella e Agrobacterium, a atividade do operon foi analisada em diferentes condições como crescimento das células repórter in planta, co-cultivo com bactérias endofíticas e deficiência nutricional. Entretanto, uma maior atividade do operon em Xylella e Agrobacterium foi detectada apenas na condição de biofilme. Células de Agrobacterium aderidas em raiz de tabaco também apresentaram maior expressão do gene repórter quando comparadas às células em suspensão. Mutantes de Agrobacterium deficientes em BigR (bigR-) apresentam maior expressão do gene repórter, confirmando que BigR age como o repressor transcricional do operon. A quantificação da formação de biofilme das células mutante e selvagem revelou uma maior densidade de biofilme no mutante bigR- em superfície de vidro e também maior quantidade de células aderidas em raiz de tabaco, indicando que o operon pode estar envolvido com o processo de adesão ou desenvolvimento do biofilme bacteriano. Do ponto de vista estrutural, foi mostrado que a proteína BigR truncada no N-terminal (?BigR) encontra-se estruturada na forma de trímero, diferindo do observado para as proteínas com domínio HTH que em geral formam dímeros e monômeros. BigR é estável termicamente, começando a perder estrutura à 74oC, mas retendo um sinal residual de a-hélice até 90oC. Tratamentos com altas concentrações de (NH4) SO 2 4 interferiram na ligação da proteína ao DNA alvo e no conteúdo de estrutura secundária sem alterar, contudo, sua estabilidade térmica. A purificação e cristalização da proteína ?BigR resultou na coleta de alguns conjuntos de dados da proteína nativa e derivada, através de soaking ou marcada com SeMet. Apesar dos dados obtidos serem de boa qualidade, até o momento, não foi possível a resolução da estrutura cristalográfica desta proteína Abstract: The XF0767 gene from Xylella fastidiosa is located in an operon composed by a set of genes (XF0768-XF0767-XF0766-XF0765-XF0764) of unknown function. This operon is conserved in a number of plant-associated bacteria including Agrobacterium tumefaciens, Mezorhizobium loti e Sinorhizobium meliloti. The DNA region upstream of the operon has canonical sequences corresponding to ¿35 and ¿10 elements found in sigma70-regulated promoters. The aim of this work was to elucidate the biological function of the protein encoded by XF0767, named BigR (biofilm growth-associated repressor), as a transcriptional regulator and its importance to the bacteria. BigR binds to an inverted repeat sequence (9-4-9) located in the ¿10 region of the XF0768-0764 operon promoter. This sequence was named BigRbox. BigR repressed transcription of its own operon upon binding to the BigRbox in Xylella fastidiosa and Agrobacterium tumefaciens. Mutations in the BigRbox significantly affected the repressor binding and abolished transcription of the reporter gene in both bacteria, indicating that BigR compete with the RNA polymerase for the same promoter site. BigR is similar to HTH transcriptional factors of the SmtB/ArsR family, which control tolerance and detoxification of heavy metals in prokaryotes. Despite the similarities, BigR does not appear to function as a metal sensor, as initially predicted. Although binding of BigR to its target DNA was diminished in the presence of cadmium, copper and iron, operon regulation in response to metals was not demonstrated in vivo. In addition, Agrobacterium mutants deficient in BigR did not show changes in growth rates in the presence of metals. BLH is an unusual beta-lactamase-like hydrolase coded by the XF0768 gene. To gain insights into the possible function of the operon, the activity of reporter cells was observed in the presence of different compounds and conditions including in planta growth, effect of endophytic competition and nutrient deficiency. Significantly, an increased operon activity was observed in Xylella and Agrobacterium biofilms. Agrobacterium cells attached to tobacco roots also showed high levels of reporter gene expression in comparison to cells in suspension. A. tumefaciens mutants deficient in the BigR showed constitutive expression of the operon, confirming that BigR acts as a transcriptional repressor. Biofilm quantification showed increased biofilm formation in glass surfaces as well as in tobacco roots, indicating that the operon may play a role in cell adherence or biofilm development. Structurally, the truncated BigR protein (?BigR) is a trimmer in solution, as opposed to most HTH regulators known, which are usually found as dimmers or monomers. BigR is stable at high temperatures (74oC); however, treatments with high concentrations of ammonium sulfate interfere with the protein secondary structure and its DNA binding capacity, without affecting its thermal stability. Good quality X-ray diffraction data were collected for the native and derivative ?bigR protein; however, structure resolution was not possible probably due to problems with the crystals Doutorado Genética de Microorganismos Doutor em Genética e Biologia Molecular
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- 2021
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13. Composição microbiologica e bioquimica do biofilme dental formado em diferentes tempos e sua relação com a desmineralização do esmalte
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Vale, Glauber Campos, Tabchoury, Cinthia Pereira Machado, 1969, Serra, Mônica Campos, Graner, Renata de Oliveira Mattos, Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba, Programa de Pós-Graduação em Odontologia, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Sucrose ,Biofilm ,Dental enamel ,Esmalte dentário ,Biofilmes ,Sacarose - Abstract
Orientador: Cinthia Pereira Machado Tabchoury Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba Resumo: O biofilme dental exposto a sacarose in situ por 13 dias ou mais apresenta altas concentrações de polissacarídeos extra-celulares (PEC), altas contagens da lactobacilos e baixa concentração inorgânica. Entretanto, essas mudanças e suas conseqüências em estágios inferiores de formação de biofilme são desconhecidas. Assim, o objetivo deste estudo foi avaliar a composição microbiológica e bioquímica do biofilme dental formado na presença de sacarose ou glicose + frutose em diferentes tempos, com a finalidade de observar a dinâmica de maturação do biofilme e sua relação com a desmineralização do esmalte. Doze voluntários adultos utilizaram em 3 fases cruzadas de 14 dias, um dispositivo intra-oral palatino contendo 6 blocos de esmalte dental humano, os quais foram expostos 8 vezes ao dia aos seguintes tratamentos: água destilada e deionizada (T1), solução de glicose 10% + frutose a 10% (T2) ou solução de sacarose a 20% (T3). O biofilme foi coletado após 3, 7 e 14 dias de formação e avaliado quanto à composição microbiológica e bioquímica. A análise microbiológica consistiu nas contagens de microrganismos totais (MT), estreptococos totais (ET), estreptococos do grupo mutans (EM), lactobacilos (LB), %EM/MT, %EM/ET e LB/MT. As variáveis bioquímicas avaliadas foram Ca, F, Pi, polissacarídeos intra (PIC) e extracelulares (PEC) no biofilme. Nos espécimes dentais, a perda mineral do esmalte seccionado longitudinalmente foi determinada. Maior desmineralização foi encontrada nos blocos submetidos ao T3 do que nos tratados com T1 e T2 (p < 0,05), sendo a perda mineral considerada significante a partir de 7 dias (p < 0,05). As concentrações de F, Ca e Pi no biofilme dental foram menores no T2 e T3 do que no T1 (p < 0,05), ), sendo que para F e Ca não houve diferença entre os tempos (p > 0,05) e para Pi, 7 e 14 dias mostraram maiores concentrações que no biofilme de 3 dias (p < 0,05). As concentrações de PIC foram significantemente maiores no T2 e T3 do que no T1 (p < 0,05), havendo um aumento com 7 e 14 dias, enquanto as de PEC foram maiores no T3 do que no T1 e T2 (p < 0,05), não mostrando diferença entre os tempos. Em relação à composição microbiana, os resultados mais evidentes foram em relação à contagem de LB e %LB/MT que apresentaram-se maiores no biofilme tratado com T2 e T3 do que no T1, entretanto essa diferença só foi observada a partir do 7o. dia (p < 0,05). Os resultados sugerem que mudanças na composição do biofilme formado na presença de sacarose já são evidentes a partir do 3o. dia de formação, entretanto a perda mineral só é significativa com 7 dias Abstract: Dental biofilm exposed in situ to sucrose for 13 days or longer presents high concentration of extracellular polysaccharide (EPS), high lactobacilli counts and low inorganic concentration. However, these changes and their consequences at earlier stages of biofilm formation are unknown. Thus, the aim of this study was to evaluate the microbiological and biochemical composition of dental biofilm formed in the presence of sucrose or glucose + fructose at different periods, in order to observe its dynamic of maturation and its relationship with enamel demineralization. Twelve adult volunteers wore, for 3 crossover phases of 14 days, an intra-oral palatal appliance containing 6 human enamel blocks, which were exposed 8 times/day to the following treatments: distilled and deionized water (T1), 10% glucose + 10% fructose solution (T2) or 20% sucrose solution (T3). The biofilm was collected after 3, 7 and 14 days of formation and evaluated with regard to microbiological and biochemical composition. Microbiological analyses consisted in counts of total microorganisms (TM), total streptococci (TS), mutans streptococci (MS), lactobacilli (LB), %MS/TM, %MS/TS and %LB/TM. The biochemical variables evaluated were F, Ca, Pi, intra (IPS) and extracellular (EPS) polysaccharides. In dental specimens, enamel cross-sectional mineral loss was determined. Higher mineral loss was found in enamel blocks treated with T3 than those exposed to T1 and T2 (p < 0.05), however only with 7 days the mineral loss was considered significant (p < 0.05). The concentrations of F, Ca and Pi in dental biofilm were lower in T2 and T3 than in T1 (p < 0.05). Also, for F and Ca no difference was observed among the periods (p > 0.05) and for Pi, 7 and 14-day biofilm showed higher concentrations than 3-day biofilm (p < 0.05). IPS concentrations were significantly higher in T2 and T3 than in T1 (p < 0.05), showing increased concentrations with 7 and 14 days (p < 0.05), whereas EPS concentration did not show statistical difference among the periods (p > 0.05), but showed higher values in T3 than in T1 and T2 (p < 0.05). With respect to microbiological composition, the most evident results were related to LB counts and % LB/TM that showed higher values in T2 and T3 than in T1 (p < 0.05), but this difference was observed only with 7-day biofilm (p < 0.05). The results suggest that the changes on composition of biofilm formed under sucrose exposure are evident at 3 days of formation, however the mineral loss is only significant with 7 days of biofilm formation Mestrado Cariologia Mestre em Odontologia
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- 2021
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14. Caracterização dos padrões de expressão de glucosiltransferases B e C, da proteina ligante de glucano B e de possiveis genes reguladores em genotipos distintos de Streptococcus mutans
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Stipp, Rafael Nobrega, 1982-2020, Mattos-Graner, Renata de Oliveira, 1971, Mayer, Marcia Pinto Alves, Gonçalves, Reginaldo Bruno, Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Biofilm ,Reverse transcriptase polymerase chain reaction ,Biofilmes ,Reação em cadeia da polimerase via transcriptase reversa - Abstract
Orientador: Renata de Oliveira Mattos-Graner Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba Resumo: Streptococcus mutans são os principais patógenos da cárie dentária, pois são capazes de se acumular no biofilme dentário na presença de sacarose, e sob condições altamente acidogênicas, promovem a desmineralização dentária. As glucosiltransferases B (GtfB) e C (GtfC) produzidas por S. mutans são fundamentais neste processo, porque catalisam a síntese de glucanos extracelulares insolúveis, a partir da sacarose. A proteína ligante de glucano B (GbpB) parece também participar do acúmulo de S. mutans nos biofilmes, embora por processos ainda não compreendidos. Pouco se sabe sobre os mecanismos que regulam a expressão dos genes que codificam essas proteínas de virulência (gtfB, gtfC e gbpB). Neste sentido, objetivamos caracterizar o padrão de expressão dos genes gtfB, gtfC e gbpB e de seus possíveis genes regulatórios (vicR, comE, ciaR e rr11) em genótipos distintos de S. mutans. Para isso, foram realizadas análises de transcrição reversa-PCR semi-quantitativa (RT-PCR) dos genes alvo em diferentes fases de curvas de crescimento planctônico, em meio Brain Heart Infusion, a 37°C, em condições de anaerobiose. RNAs das células nas diferentes fases de crescimento foram extraídos e submetidos a reações de transcriptase reversa com primers arbitrários, para obtenção dos cDNAs totais. Análises de PCR semi-quantitativas dos cDNAs foram então realizadas com primers específicos e normalizados pela expressão do gene housekeeping 16SRNA, cuja expressão foi constante nas condições experimentais estudas. Os padrões de transcrição de gtfB e gtfC foram específicos ao background genético da cepa estudada. Os níveis de transcritos de gtfB e de gtfC foram coordenados durante fases específicas de crescimento, mas divergências nas curvas expressão dos mesmos ocorreram em grande parte dos genótipos. Os níveis de transcritos de gbpB foram também variáveis entre cepas, mas assumiram padrão independente de genes gtf e foi caracterizado por menores variações entre as diferentes fases de crescimento. Os genes regulatórios demonstraram picos de expressão nas fases log e/ou estacionária de crescimento, de acordo com o genótipo testado. Os resultados indicam que o padrões de expressão dos genes estruturais (gtfB, gtfC e gbpB) e regulatórios são cepa-específicos e que gtfB e gtfC são regulados por sistemas independentes, os quais parecem ser ativados em fases distintas de crescimento Abstract: Streptococcus mutans, the main pathogen of dental caries, have the capacity to accumulate in the dental biofilm in the presence of sucrose, under highly acidic conditions that are responsible for teeth demineralization. The glucosyltransferases B (GtfB) and C (GtfC) produced by S. mutans are essential in this process, because catalyze the synthesis of water-insoluble from sucrose. The Glucan-binding protein B (GbpB) appears to also participate in S. mutans accumulation, but under processes that are still unclear. Little is known about the mechanisms that regulate expression of genes encoding these proteins (gtfB, gtfC and gbpB). In this sense, we aimed to characterize the patterns of transcription of gtfB, gtfC and gbpB in distinct S. mutans genotypes. For that purpose, semi-quantitative analysis of reverse transcription¿PCR (RT-PCR) were performed in strains at different phases of the growth curves in Brain Heart Infusion broth bath cultures at 37°C, under anaerobiosis. RNAs were extracted from cells at different growth phases, and applied in reactions of reverse transcription with arbitrary primers to yield total cDNAs. Semi-quantitative PCR reactions were then performed with the cDNAs using specific primers to each target gene, and normalized by the expression of the housekeeping gene 16SRNA, whose expression remained constant at the experimental conditions. Patterns of expression of gtfB and gtfC were specific to the strain background. Transcriptions of gtfB e de gtfC were coordinated in specific phases of growth, but the curves of transcription diverged at different phases in the majority of the genotypes studied. The levels of gbpB transcripts were variable between strains and assumed an independent pattern when compared with gtf genes. The levels of gbpB transcripts were characterized by lesser variations between the different phases of growth. The regulatory genes have shown peaks of expression at log and/or stationary phases of growth and the curves of transcript levels were strain-dependent. The results indicate that patterns of expression of gtfB, gtfC and gbpB and regulatory genes are strain-specific, and that gtfB and gtfC are regulated by distinct systems that may be activated at distinct phases of growth Mestrado Microbiologia e Imunologia Mestre em Biologia Buco-Dental
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- 2021
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15. Identification and characterization of bacterial biofilm production in clinical isolates of Staphylococcus spp. against antimicrobials
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Carlos Alberto Medeiros Neto, Sibele Ribeiro de Oliveira, Lamartine Rodrigues Martins, Mariana Quitéria de Morais Silva, Igor Vasconcelos Rocha, and Maria Izabelly Silva Pimentel
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Hemocultura ,Gram-positive bacteria ,Staphylococcus ,Erythromycin ,Infectious and parasitic diseases ,RC109-216 ,Biology ,medicine.disease_cause ,Azithromycin ,biofilmes ,Microbiology ,Levofloxacin ,medicine ,Internal medicine ,Biofilm ,General Medicine ,biochemical phenomena, metabolism, and nutrition ,biology.organism_classification ,RC31-1245 ,Staphylococcus aureus ,hemocultura ,Medicine ,Coagulase ,staphylococcus ,Biofilmes ,medicine.drug - Abstract
Justification and Objectives: Circulating blood is sterile and the presence of microorganisms can be of clinical interest, especially in the hospital environment, being able to cause infectious processes and substantially increase morbidity and mortality. The objective of this work was to characterize the isolates of the genus Staphylococcus spp. from bloodstream infections as to the production of bacterial biofilm and resistance to the main antimicrobials used in clinical practice. Methods: Blood cultures were collected with an indication of positivity for bacterial growth from multiple sectors of the study hospital, which were subsequently processed to identify the bacterial genus through the use of phenotypic tests for Gram positive bacteria. The verification of the resistance profile was performed following the Kirby-Bauer disk diffusion. The identification of the production and quantification of the bacterial biofilm occurred following the protocol described by O’toole (2010). Results: The most frequent clinical isolate was Coagulase negative Staphylococci 38 (54.29%), followed by Staphylococcus aureus 32 (45.71%). Resistance to erythromycin, norfloxacin, levofloxacin and azithromycin was observed in most isolates (70%). Regarding methicillin, more MRSA (59.38%) than MR-CONS (47.37%) were isolated. The ICU was the place where the formation of the biofilm showed indicative data of greater adherence, which was associated with MRSA strains. Conclusion: The bacterial isolates associated with bloodstream infections showed high resistance to antimicrobials. The presence of MRSA and MR-CONS with strong and/or moderate biofilm production capacity represents a greater risk to the health of patients affected by infections caused by these agents.
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- 2021
16. Aplicação e avaliação de revestimento à base de biopolímeros em embalagens de poli (etileno tereftalato) (PET) para alimentos
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Leber, Ana Silvia Machado Lettry, 1974, Anjos, Carlos Alberto Rodrigues, 1957, Fakhouri, Farayde Matta, Cabral, Antônio Carlos Dantas, Bolini, Helena Maria André, Schmidt, Flavio Luis, Soares, Beatriz Maria Curtio, Universidade Estadual de Campinas. Faculdade de Engenharia de Alimentos, Programa de Pós-Graduação em Tecnologia de Alimentos, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Biofilm ,Polyesters ,Biopolímeros ,Plastic ,PET (Polietileno Tereftalato) ,Biopolymers ,Coatings ,Packaging ,Revestimentos ,Plásticos ,Poliésteres ,Embalagem de alimentos ,Biofilmes ,PET (Polyethylene terephthalate) - Abstract
Orientadores: Carlos Alberto Rodrigues Anjos, Farayde Matta Fakhouri Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Resumo: Este trabalho teve como objetivo geral a aplicação de revestimentos de fontes biodegradáveis e renováveis em embalagens plásticas de poli (etileno tereftalato) (PET) com a finalidade de formar películas capazes de manterem-se estáveis e aderidas à superfície externa e avaliar o potencial destes revestimentos em relação às propriedades físicas, físico-químicas, barreira ao oxigênio e ao vapor de água, além de análises sensoriais visuais das embalagens revestidas. Os testes preliminares incluiram diferentes combinações de soluções de amido e gelatina e diferentes tipos de amidos, com a finalidade de encontrar as melhores condições de aplicação manual e de melhor aderência. Inicialmente foi realizado um estudo de caracterização do amido de mandioca, gelatina e mistura de ambos. Foi possível observar que esses dois materiais influenciaram o comportamento das soluções formadoras de películas, além dos processos de gelatinização e retrogradação. As soluções foram aplicadas nas embalagens por imersão e condicionadas e estabilizadas em câmaras climatizadas. Os resultados mostraram que os revestimentos aplicados promoveram boa melhora de certas propriedades (como barreiras a gases e à luz) das embalagens e a formulação que se mostrou com melhores resultados para a taxa de permeabilidade ao oxigênio (TPO2), à transmissão de luz e a mais estável à resistência térmica foi a de proporção 4 partes de amido para 1 de gelatina (4A:1G). Também foi verificado que soluções com maior porcentagem de amido promoveram menores valores de TPO2, ou seja maior barreira e melhor proteção à embalagem revestida. Em relação às análises sensoriais visuais, observou-se que as amostras com maior porcentagem de amido, apresentaram maior opacidade, percebida pelos avaliadores, porém quando as mesmas amostras foram acondicionadas com produto simulante, essa diferença não foi percebida de maneira significativa, não afetando a aparência. Conclui-se que a aplicação de revestimentos provenientes de fontes renováveis pode ser uma alternativa de barreira a algumas características de embalagens atualmente utilizadas no mercado de alimentos, o que pode contribuir com a diminuição do impacto ambiental uma vez que possui uma camada biodegradável Abstract: The objective of this research was to apply biobased coatings of biodegradable and renewable sources on plastic PET packages, in order to form biofilms able to remain stable and adhered to the external surface and to evaluate the potential of these coatings in relation to the physical, physical chemical, oxygen and water vapor barrier, as well as visual sensorial analysis of the coated packages. Preliminary tests included different combinations of starch and gelatin solutions in order to find the best conditions for manual application and better adherence. Initially, a characterization study of cassava starch, gelatin and a mixture of both was carried out. It was possible to observe that these two materials influenced the behavior of the film-forming solutions, besides the processes of gelatinization and retrogradation. The solutions were applied in the packages by immersion and condicions and stabilized in climatized chambers. The results showed that the applied coatings promoted better improvement of some properties (oxygen, water vapor and light barriers) of the packages and the formulation that showed the best results for the oxygen permeability rate (TPO2), for light transmission and the most stable thermal resistance was the proportion 4 starch portions to 1 gelatin (4A: 1G). It was also verified that solutions with higher percentage of starch promoted smaller values of TPO2 values, ie higher barrier and better protection to the coated package. In relation to the visual sensorial analyzes, it was observed that the samples with higher starch percentage presented higher opacity, perceived by the tasters, but when the same samples were conditioned with simulant product, this difference was not perceived in a significant way, not affecting the appearance. The results that showed the potencial development and industrial application are the formulations with the two materials (starch and gelatin) together, because these both have synergy and generated the best stability and performance results with the best protection to improve the barriers properties of the package. The conditions that showed the best barrier and the best adhesion and application performance results were chosen to realize visual sensory evaluation. It is concluded that the application of biobased coatings may be an alternative to improve barrier to some packaging characteristics currently used in the food market, which factor may help to reduce the impact to environment, because this new packaging concept has a biobased layer Doutorado Embalagens de Alimentos Doutora em Tecnologia de Alimentos
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- 2021
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17. Antimicrobial activity of plants from Brazilian Cerrado against Streptococcus mutans
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Berto, Luciana Aranha, 1985, Rosalen, Pedro Luiz, 1960, Groppo, Francisco Carlos, 1966, Oshima-Franco, Yoko, Motta, Cristiane de Cassia Bergamaschi, Franco, Gilson Cesar Nobre, Müller, Karina Cogo, Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba, Programa de Pós-Graduação em Odontologia, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Streptococcus mutans ,Biofilm ,Atividade antimicrobiana ,Lantana ,Antimicrobial agents ,Biofilmes - Abstract
Orientadores: Pedro Luiz Rosalen, Francisco Carlos Groppo Texto em português e inglês Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba Resumo: Apesar do constante desenvolvimento do conhecimento, prevenção e tratamento da cárie dental, esta doença continua tendo alta prevalência no Brasil e no mundo. Por este motivo, tem crescido o interesse por novos agentes farmacológicos que possam auxiliar no controle do biofilme dental, atuando contra o principal microrganismo associado ao desenvolvimento da cárie, o Streptococcus mutans. Desta forma, o objetivo deste trabalho foi avaliar a atividade antimicrobiana do extrato de quatro plantas do cerrado brasileiro (e suas frações) contra S. mutans UA159. Extratos hidroalcoólicos de Lantana camara (Lc), Copaifera langsdorffii (Cl), Psidium guajava (Pg) e Cochlospermum regium (Cr), foram submetidos a testes de avaliação da atividade antimicrobiana para determinação das concentrações inibitória (CIM) e bactericida (CBM) mínima, inibição da aderência e queda de pH em solução. O extrato bruto das quatro plantas apresentaram potencial antimicrobiano e foram fracionados por gradiente de polaridade, sendo obtidas, para cada extrato, as frações hexânica (FHx), clorofórmica (FCh), acetato de etila (FAc) e aquosa (FAq). Estas foram submetidas aos experimentos já citados para determinação da(s) fração(ões) ativa(s) de cada extrato, selecionadas com base nos resultados dos testes de atividade antimicrobiana e no rendimento. Foram selecionadas, para a etapa subsequente de avaliação em biofilme, 6 frações ativas: Lc-FHx e Lc-FCl, ambas com CIM = 15,6 µg/ml, e rendimento 9,5 e 17,5%, respectivamente; Cl-FHx, que apresentou CIM = 15,6 µg/ml, atividade inibitória sobre a queda de pH em solução e rendimento igual a 21%; Pg-FHx, com CIM = 125 µg/ml, 93,4% de inibição da aderência na concentração de 62,5 µg/ml e rendimento igual a 2,0%; Cr-FHx, com CIM = 125 µg/ml, apresentou atividade inibitória sobre queda de pH do meio e rendimento igual a 1,0% e Cr-FAq, que obteve CIM elevado, entretanto, inibiu 86,7% de aderência bacteriana, na concentração de 62,5 µg/ml, sendo o rendimento desta fração 32%. As frações selecionadas foram submetidas a avaliações complementares, como: viabilidade bacteriana (time kill), inibição de formação e queda de pH em biofilme de S. mutans, utilizando discos de hidroxiapatita. Nos testes em biofilme, destacaram-se três frações: Lc-FHx, que em concentração 20xCIM, proporcionou redução na viabilidade do microrganismo e diminuição da formação do biofilme tratado diariamente por 5 dias; Lc-FCh, que em concentração equivalente a 20xCIM, reduziu a formação de biofilme e Cl-FHx, que além de reduzir a formação de biofilme na concentração de 20xCIM, interferiu na viabilidade do microrganismo, nas duas concentrações testadas (10xCIM e 20xCIM). A composição química das frações ativas em biofilme foi analisada por CG-EM. As demais frações testadas nesta etapa não diferiram do controle negativo (veículo) nos testes aplicados. Nenhuma das frações avaliadas afetou a redução de pH do meio pelo biofilme. Em conclusão, as frações com polaridades baixa ou intermediária das espécies Lantana camara e Copaifera langsdorffii mostraram ter potencial para gerar novos compostos anti-cárie de origem natural, tendo apresentado atividade antimicrobiana sobre o biofilme formado por S. mutans Abstract: Despite the continuous development of knowledge, prevention and treatment of dental caries, the disease continues to have a high prevalence in Brazil and worldwide. For this reason, there is been a strong interest for new pharmacological agents that can assist biofilm control, acting against the main microorganism associated with the development of caries, Streptococcus mutans. Thus, the aim of this study was to evaluate the antimicrobial activity of the extract of four plants from Brazilian cerrado (and its fractions) against S. mutans UA159. Hydroalcoholic extracts of Lantana camara (Lc), Copaifera langsdorffii (Cl), Psidium guajava (Pg) and Cochlospermum regium (Cr) were evaluated by means of antimicrobial tests for the determination of minimum inhibitory (MIC) and bactericidal (MBC) concentrations, inhibition of adhesion and pH-drop of S. mutans. The crude extract of four plants showed antimicrobial potential and were fractionated by polarity gradient, and 4 fractions were obtained for each extract: hexane (FHx), chloroform (FCh), ethyl acetate (FAc) and aqueous (FAq) fractions. These fractions were subjected to previously mentioned tests to determine the active fraction(s) of each extract. For the subsequent evaluation step in biofilm, 6 active fractions were selected: Lc-FHx and Lc- FCl, both with MIC = 15.6 µg/ml, and yield of 9.5% and 17.5%, respectively; Cl-FHx, which showed MIC = 15.6 µg/ml, an inhibitory activity on the pH drop in solution and yield of 21%; Pg-FHx with MIC = 125 µg/ml, 93.4% of inhibition of adhesion in the concentration of 62.5 µg/ml and yield of 2.0%; Cr-FHx, with MIC = 125 µg/ml, an inhibitory activity against pH drop and a yield of 1.0% and Cr- Aq, which showed a high MIC value, however, it inhibited 86.7% of bacterial adhesion at a concentration of 62.5 µg/ml, and had a yield of 32%. The selected fractions were subjected to additional tests as bacterial viability (time-kill), inhibition of formation and pH drop in biofilms of S. mutans, using hydroxyapatite disks. Three active fractions stood out in tests on biofilm: Lc-FHx which decreased the viability of the microorganism and biofilm formation in the concentration of 20xMIC, Lc- FCx, which reduced biofilm formation in the 20xMIC concentration, and Cl ¿ FHx, which reduced biofilm formation in the 20xMIC concentration and interfered with the viability of the microorganism at the two tested concentrations (10xMIC and 20xMIC). The chemical composition of active fractions was analyzed by GC-MS. The other fractions tested in biofilm did not differ from the negative control (vehicle). None of the evaluated fractions affected the pH drop by biofilm. In conclusion, Lantana camara and Copaifera langsdorffii fractions with low or intermediate polarities showed potential to generate new naturally occurring anticarie compounds and presented antimicrobial activity against biofilms formed by S. mutans Doutorado Farmacologia, Anestesiologia e Terapêutica Doutora em Odontologia
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- 2021
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18. Comportamento de 'Clostridium difficile' em diferentes meios de cultivo e carne embalada a vácuo, capacidade de formação de biofilmes e controle por sanitizantes
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Tsuchiya, Ana Claudia, 1987, Kuaye, Arnaldo Yoshiteru, 1952, Kabuki, Dirce Yorika, 1964, Silva, Nathalia Cristina Cirone, Bromberg, Renata, Junqueira, Valeria Christina Amstalden, Universidade Estadual de Campinas. Faculdade de Engenharia de Alimentos, Programa de Pós-Graduação em Tecnologia de Alimentos, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Spores ,Sanitizantes ,Multirresistência ,Biofilm ,Sanitizers ,Clostridium difficile ,Esporos ,Biofilmes ,Multiresistance - Abstract
Orientadores: Arnaldo Yoshiteru Kuaye, Dirce Yorika Kabuki Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Resumo: Clostridium difficile é um bacilo anaeróbio responsável por doença intestinal associada ao tratamento prévio com antibióticos, manifestando desde uma diarreia leve até casos graves de colite pseudomembranosa. Os casos de infecção estão relacionados à contaminação em hospitais, porém pesquisas recentes sugerem possível associação ao consumo de alimentos contaminados, pois C. difficile já foi isolado de animais de produção. O C. difficile é um micro-organismo capaz de aderir e formar biofilmes em superfícies de equipamentos e utensílios utilizados no processamento de carnes, causando um elevado risco de contaminação de alimentos. Desta forma os objetivos do estudo foram: a) avaliar o comportamento de cepas de C. difficile isolados de carnes em diferentes meios de cultura, PYG (Peptone yeast extract glucose) e BHI (Brain heart infusion), a 4 ºC e 7 ºC por 28 dias e, a 15 ºC por 10 dias e em carnes embaladas a vácuo a 7 ºC e 15 ºC por 35 e 15 dias, respectivamente; b) avaliar a capacidade de adesão e/ou formação de biofilme de C. difficile (VPI 10463 e LHCD 809) em diferentes matrizes, BHI, BHI modificado com cisteína e BHI modificado para pH 5,6-5,8 sob duas temperaturas, 15 ºC e 25 ºC por até 10 dias, em superfície de cupons de aço inoxidável AISI 304; c) avaliar estratégias para controle e inibição de C. difficile, dentre elas aplicação de sanitizantes em biofilmes formados após 6 dias de contato e sobre suspensão de esporos de C. difficile; d) avaliar o perfil de susceptibilidade de cepas isoladas de carnes a 8 antimicrobianos (ampicilina, clindamicina, ceftizoxime, moxifloxacina, metronidazol, tetraciclina, ceftriaxone e vancomicina). Os resultados revelaram o efeito bacteriostático da estocagem às temperaturas de 4 ºC e 7 ºC, no entanto, um abuso de temperatura (15 ºC) proporcionou a multiplicação de C. difficile. O desenvolvimento de C. difficile VPI 10463 em carnes embaladas a vácuo é favorecido pelo aumento de temperatura. Tanto a cepa de C. difficile padrão VPI 10463, quanto a cepa LHCD 809 isolada de carne de frango foram capazes de aderir e formar biofilmes multiformes em superfície de aço inoxidável. Embora o sanitizante a base de hipoclorito de sódio tenha apresentado maior redução do biofilme de C. difficile a sua eliminação não foi total, indicando a necessidade de um processo mais efetivo de higienização. Para eliminação de esporos de C. difficile o hipoclorito de sódio foi o agente com maior efeito esporicida, seguido do ácido peracético. A biguanida e o quaternário de amônio não apresentaram nenhuma atividade sobre os esporos de C. difficile. A multirresistência a pelo menos três agentes antimicrobianos foi encontrada em 36,4% dos isolados, o que evidência a importância do monitoramento periódico para avaliar o surgimento de cepas resistentes. Dessa forma, os alimentos in natura e os processados representam um risco para saúde pública, agindo como possíveis veículos para transmissão de C. difficile, portanto, estratégias adequadas para reduzir a contaminação de alimentos são extremamente recomendadas Abstract: Clostridium difficile is an anaerobic bacillus responsible for intestinal disease associated with previous treatment with antibiotics, ranging from mild diarrhea to severe cases of pseudomembranous colitis. Infection cases are related to contamination in hospitals, but recent research suggests a possible association with the consumption of contaminated foods, since C. difficile has already been isolated from production animals. C. difficile is a microorganism capable of adhering and forming biofilms on surfaces of equipment and utensils used in meat processing, causing a high risk of food contamination. In this way the objectives of this study were: a) to evaluate the behavior of C. difficile strains isolated from meat in different culture media, PYG (Peptone yeast extract glucose) and BHI (Brain heart infusion) at 4 ºC and 7 ºC for 28 days and at 15 ºC for 10 days and in vacuum packed meats at 7 ºC and 15 ºC for 35 and 15 days, respectively; b) to evaluate the adhesion and/or biofilm formation capacity of C. difficile (VPI 10463 and LHCD 809) in different matrices, BHI, cysteine-modified BHI and BHI modified to pH 5.6-5.8 under two temperatures, 15 ºC and 25 ºC for up to 10 days, on stainless steel AISI 304 coupon surfaces; c) to evaluate strategies for C. difficile control and inhibition, among them application of sanitizers in biofilms formed after 6 days of contact and on spore suspension of C. difficile; d) to evaluate the susceptibility profile of strains isolated from meat to 8 antimicrobials (ampicillin, clindamycin, ceftizoxime, moxifloxacin, metronidazole, tetracycline, ceftriaxone and vancomycin). The results revealed the bacteriostatic effect of storage at temperatures of 4 ºC and 7 ºC, however, a temperature abuse (15 ºC) resulted in the multiplication of C. difficile. The development of C. difficile VPI 10463 in vacuum packed meats is favored by the increase in temperature. Both the C. difficile strain VPI 10463 and the LHCD 809 strain isolated from chicken meat were able to adhere and form multiform biofilms on stainless steel surfaces. Although the sanitizer based on sodium hypochlorite showed a greater reduction of C. difficile biofilm, its elimination was not complete, indicating the need for a more effective hygienization process. For elimination of C. difficile spores sodium hypochlorite was the agent with the highest sporicidal effect, followed by peracetic acid. Biguanide and quaternary ammonium showed no activity on C. difficile spores. The multiresistance of at least three antimicrobial agents was found in 36.4% of the isolates, evidencing the importance of periodic monitoring to evaluate the emergence of resistant strains. Thus, in natura and processed foods represent a risk to public health, acting as possible vehicles for transmission of C. difficile, therefore, adequate strategies to reduce food contamination are highly recommended Doutorado Tecnologia de Alimentos Doutora em Tecnologia de Alimentos CAPES
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- 2021
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19. Estudos estruturais e funcionais de proteínas relacionadas à patogenicidade de Xylella fastidiosa
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Santos, Clelton Aparecido dos, 1984, Souza, Anete Pereira de, 1962, Aparicio, Ricardo, 1971, Vilas-Bôas, Laurival Antonio, Tasic, Ljubica, Kobarg, Jörg, Peroni, Luis Antonio, Universidade Estadual de Campinas. Instituto de Biologia, Programa de Pós-Graduação em Genética e Biologia Molecular, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Xylella fastidiosa ,Biofilm ,Tol-Pal system ,DsbC ,5'-Nucleotidase ,Biofilmes ,Sistema Tol-Pal - Abstract
Orientadores: Anete Pereira de Souza, Ricardo Aparício Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia Resumo: Xylella fastidiosa é uma bactéria responsável por inúmeras doenças de plantas em culturas economicamente importantes ao redor do mundo, incluindo a clorose variegada dos citros. Após a infecção de seu hospedeiro, as células de X. fastidiosa é apta a formarem uma estrutura de biofilme que bloqueia os vasos xilemáticos, levando a uma condição de estresse hídrico na planta hospedeira e desencadeando o desenvolvimento da doença. Tendo como estímulo a relevância econômica da citricultura para o Brasil e, visando reduzir os prejuízos provocados pelos problemas fitossanitários que acometem esta cultura, foi realizado um consórcio de pesquisa com o intuito de se conhecer completamente o genoma da linhagem 9a5c de X. fastidiosa. Inúmeras proteínas associadas com patogenicidade, adaptação e sobrevivência bacteriana foram identificadas, incluindo XfDsbC (proteína disulfeto isomerase), Xf5'-Nt (5'-nucelotidase), XfTolB (proteína de translocação B) e XfPal (lipoproteína associada ao peptidoglicano) que foram caracterizadas neste estudo. Empregando ferramentas de caracterização de proteínas, aspectos funcionais e estruturais destas quatro proteínas alvos foram avaliados. Dentre os resultados destaca-se a imunodetecção de XfDsbC, Xf5'-Nt, XfTolB e XfPal durante as diferentes fases de formação e desenvolvimento do biofilme de X. fastidiosa, que é tido como o principal mecanismo de patogenicidade deste fitopatógeno, confirmando a predição inicial de tais proteínas como associadas à patogenicidade bacteriana. Adicionalmente, resultados funcionais e estruturais revelaram detalhes finos do papel biológico desempenhado por cada uma das proteínas estudadas. Juntos, os resultados apresentados neste trabalho contribuem para o melhor entendimento de patogenicidade bacteriana, especialmente com respeito ao fitopatógeno X. fastidiosa Abstract: Xylella fastidiosa is a plant pathogen bacterium responsible for numerous economically important crops diseases around the world, including the citrus variegated chlorosis. Following the host infection, the X. fastidiosa cells are able to form a biofilm structure which block the xylem vessels, leading to a hydric stress condition in the host plant and triggers the disease development. Given the economic relevance of citriculture for Brazil and in order to reduce the damage caused by phytosanitary problems that affect the citrus production, a research consortium was established with the aim to elucidate the complete genome sequence of the X. fastidiosa 9a5c strain. Numerous proteins associated with bacterial pathogenicity, adaptation and survival have been identified, including XfDsbC (protein disulfide isomerase), Xf5'-Nt (5'-nucleotidase), XfTolB (protein translocation B) and XfPal (peptidoglycan-associated lipoprotein) which were characterized in this study. Using tools for protein characterization, structural and functional aspects of these four protein targets were evaluated. Among the results, we highlight the immunodetection of XfDsbC, Xf5'-Nt, XfTolB and XfPal during the different stages of X. fastidiosa biofilm formation and development which is considered the primary mechanism of pathogenicity of this pathogen. These findings, confirming the initial prediction that relates such proteins as associated with bacterial pathogenicity. Additionally, structural and functional results revealed accurate details of the biological role played by each protein studied. Taken together, the findings presented in this study contribute to a better understanding of bacterial pathogenesis, especially with regard to the plant pathogen X. fastidiosa Doutorado Genética de Microorganismos Doutor em Genética e Biologia Molecular
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- 2021
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20. Análise biomolecular de comunidades microbianas subgengivais associadas às periodontites crônica e agressiva generalizadas
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Cruz, Sergio Eduardo Braga da, Gonçalves, Reginaldo Bruno, 1966, Saito, Daniel, 1974, Grisi, Daniela Corrêa, Napimoga, Marcelo Henrique, Höfling, José Francisco, Nociti Junior, Francisco Humberto, Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba, Programa de Pós-Graduação em Biologia Buco-Dental, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Biofilm ,Clonagem molecular ,Molecular cloning ,Biofilmes - Abstract
Orientadores: Reginaldo Bruno Gonçalves, Daniel Saito Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba Resumo: Há um consenso que outros micro-organismos além de Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf) e Treponema denticola (Td) estariam correlacionados às periodontites, inclusive algumas espécies ainda não identificadas. Nosso objetivo foi estudar as microbiotas subgengivais de indivíduos com periodontite crônica generalizada (PCG) e periodontite agressiva generalizada (PAG) para avaliar diferenças entre suas microbiotas. MATERIAL E MÉTODOS-Foram selecionados 15 indivíduos com PCG e 14 com PAG. Coletou-se amostra do biofilme subgengival de uma bolsa periodontal profunda (BP-PS ? 7mm) e uma moderada (BM - PS entre 5 e 6 mm) de cada indivíduo. Foi preparado e analisado, por meio de DGGE, o perfil bacteriano entre os grupos. A similaridade e a análise de cluster do padrão de UTO's foram verificadas utilizando-se coeficiente de Jaccard e a construção do dendrograma realizada por UPGMA. Realizou-se também análise clonal direta de 10 amostras de BP de cada grupo e as sequências foram agrupadas em táxons com similaridade >97%. RESULTADOS-DGGE - No perfil de DGGE foi observada uma tendência para a formação de grupos em BP, mas não em BM, com a presença de dois grupos maiores e distintos de oito indivíduos tanto para PCG como PAG, com variação de similaridade intra-grupo entre 53,6-68,4% e 50,2-64,7%, respectivamente. Análise clonal - Foram identificados 109 táxons conhecidos a partir de 987 clones. Ao todo 44 gêneros bacterianos, 28 gêneros comuns aos dois grupos, nove que se apresentaram apenas para PCG e sete para PAG. Entre os dois grupos foram observados 34 táxons comuns, sendo 42 específicos para PAG e 37 para PCG. A espécie Tf foi detectada em 90% dos indivíduos com PCG e 80% com PAG, Pg foi detectada em 70% com PCG e 50% com PAG e Td foi detectada em 40% com PCG e 30% PAG. A espécie Aa foi encontrada em somente 20% de PCG e 30% de PAG. A espécie Filifactor alocis foi observada em altas taxas e prevalência em PCG (58 clones, 90%) e PAG (91 clones, 90%). As espécies encontradas exclusivamente por grupo com prevalência acima de dois pacientes foram: PCG: Treponema lecithinolyticum, Selenomonas dianae, Prevotella pleuritidis, Dialister pneumosintes; e para PAG: Fusobacterium nucleatum ss vincentii, Veillonella parvula, Peptococcus sp. Cepa GEA8, Streptococcus gordonii, Lautropia mirabilis, Gemella sanguinis, Afipia broomeae. Para os filotipos, PCG: Peptostreptococcaceae sp. Clone-MCE10_174, Fusobacterium sp. C-I035, Veillonellaceae sp. C-JS031; PAG: Peptostreptococcaceae sp. C-PUS9170, Treponema sp. CG093. Apesar de não haver exclusividade entre grupos, é de nota os filotipos Synergistes sp. clone W028 (80% e 60%) e o clone D084 (70% e 10%) em PCG e PAG, respectivamente. O filotipo Bacteroidetes sp. AU126 foi encontrado tanto em PCG (60%) como PAG (30%). CONCLUSÃO - O presente trabalho demonstrou por meio de DGGE uma tendência a um perfil microbiano comum entre a maioria das amostras estudadas, entretanto, sem seu completo delineamento como dois grupos distintos microbiologicamente. A análise clonal, apesar de algumas espécies específicas entre grupos, demonstrou pequenas diferenças, sem, entretanto, delinear grupos microbiologicamente específicos. Abstract: There is an agreement that not only the already known periodontopathogens, Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf) and Treponema denticola (Td) would be involved in periodontitis, but also some others micro-organisms not-yet-identified. The scope of this study is to compare the subgingival microbiota in generalized chronic periodontitis (GCP) or generalized aggressive periodontitis (GAP) subjects. MATERIAL AND METHODS - 15 subjects with GCP and 14 with GAP were enrolled. One subgingival biofilm sample from a periodontal deep pocket (DP) with PD ? 7mm and one from a moderate pocket (MP) with PD from 5 to 6 mm were harvested from each subject. The microbial profiles (OTU's) were compared between groups by DGGE and the similarity OTU profile was analyzed by Jaccard coefficient and the dendrogram and cluster analyses were made by UPGMA. The direct clonal analysis of the 16SrDNA from 10 samples of each group from DP was made. The sequences were grouped in clusters of taxa with > 97% similarity. RESULTS - DGGE - It was observed in the profile a tendency for eight subjects from each group to assemble as clusters in the DP, but not for the MP samples, with similarities between 53.6-68.4% (GCP) and 50.2-64.7% (GAP). Clonal analyses - One-hundred-and-nine already recognized taxa were obtained from 987 clones. From a total of 44 bacterial genera, 28 were common for both groups; nine were exclusive to PCG and seven to PAG subjects. It was found 34 common taxa between GCP and GAP, 37 were specific for GCP and 42 for GAP. The Tf species was found in 90% from GCP subjects and 80% from GAP subjects, Pg was found in 70% from GCP and in 50% from GAP and Td was detected in 40% from GCP and 30% from GAP. The Aa species were found in only 20% GCP subjects and in 30% from GAP. Filifactor alocis species were detected in high prevalence in both GCP (58 clones, 90%) and PAG (91 clones, 90%). The species which were detected exclusively in each group, with 20% prevalence or more were, for GCP: Treponema lecithinolyticum, Selenomonas dianae, Prevotella pleuritidis, Dialister pneumosintes; and GAP: Fusobacterium nucleatum ss vincentii, Veillonella parvula, Peptococcus sp. Cepa GEA8, Streptococcus gordonii, Lautropia mirabilis, Gemella sanguinis, Afipia broomeae. In relation to phylotypes, PCG: Peptostreptococcaceae sp. Clone-MCE10_174, Fusobacterium sp. C-I035, Veillonellaceae sp. C-JS031; PAG: Peptostreptococcaceae sp. C-PUS9170, Treponema sp. C-G093. Despite not been found exclusively for neither GCP nor GAP, the phylotypes Synergistes sp. clone W028 (80% e 60%) and clone D084 (70% e 10%) had a notable presence in GCP and GAP, respectively. The phylotype Bacteroidetes sp. AU126 was found in GCP (60%) and GAP (30%) groups. CONCLUSION - The present study demonstrated by DGGE a slight tendency to the clustering of the microbial profile of some GCP and GAP subjects, although these were not well delineated. The clonal analyses showed some differences, but also could not show GCP and GAP as microbiologic distinct profiles. Doutorado Microbiologia e Imunologia Doutor em Biologia Buco-Dental
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- 2021
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21. Influência da degradação biomecânica sobre propriedades físico-químicas de cimentos ionoméricos restauradores com diferentes composições
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Fúcio, Suzana Beatriz Portugal de, Puppin-Rontani, Regina Maria, 1959, Grande, Rosa Helena Miranda, Imparato, José Carlos Pettorossi, Uchôa, Marinês Nobre dos Santos, Consani, Simonides, Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba, Programa de Pós-Graduação em Materiais Dentários, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Cimentos de ionômeros de vidro ,Streptococcus mutans ,Degradation ,Nanotecnologia ,Biofilm ,Glass ionomer cements ,Nanotechnology ,Degradação ,Biofilmes - Abstract
Orientador: Regina Maria Puppin-Rontani Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba Resumo: A interação direta entre restauração e biofilme dentário está presente constantemente na cavidade bucal e suas conseqüências relacionam-se tanto com as características físicas e químicas do material quanto com a virulência da bactéria aderida. O objetivo deste estudo foi avaliar diferentes cimentos ionoméricos restauradores submetidos, in vitro, à biodegradação por biofilme de Streptococcus mutans e à abrasão por escovação. Cada material selecionado (Ketac N100, Vitremer, Ketac Molar Easymix e Fuji IX) foi utilizado na forma recém-manipulada ou na forma de discos, confeccionados sob condições assépticas. Enquanto o material pré-presa foi inserido em poços para o teste de difusão em ágar e análise dos halos de inibição de crescimento do S. mutans UA159 (n=8), os discos foram distribuídos em diferentes testes: a) teste de aderência desta cepa em 2 horas aos materiais, com a contagem das unidades formadoras de colônias (n=10); b) testes relacionados ao acúmulo bacteriano por sete dias (n=10) - peso úmido do biofilme, pH do meio de cultura a cada 48 horas (renovação do meio) e flúor liberado neste mesmo meio. Após os sete dias de biodegradação, os discos foram lavados e avaliados quanto à rugosidade e micro-morfologia de superfície. Como grupo controle, dez discos foram mantidos em umidade relativa pelo mesmo período para avaliação da superfície. A abrasão por escovação (degradação mecânica) foi realizada em seguida, e os espécimes foram reavaliados. Os dados obtidos nos testes de difusão, aderência e peso úmido do biofilme foram avaliados estatisticamente pelos testes de Kruskal-Wallis e Mann-Whitney, enquanto os dados de pH, flúor e rugosidade foram avaliados por ANOVA e Tukey (?=5%). Não houve diferença estatisticamente significante entre os materiais quanto à aderência inicial (p=0,6272) e peso final do biofilme (p=0,9612). Entretanto, Vitremer apresentou os maiores halos de inibição, valores de pH nas primeiras 48 horas superiores ao Ketac N100 e Fuji IX, e liberação de flúor superior ao Ketac N100 e Ketac Molar Easymix durante todo o período experimental. Ketac N100 apresentou maior halo de inibição que os materiais convencionais e menor liberação de flúor, com uma diminuição nos valores ao longo do tempo de aproximadamente doze vezes. Quanto à rugosidade, houve interação entre os três fatores: material, meio de armazenamento (umidade x biofilme) e abrasão (antes x depois). Vitremer foi o único material que não apresentou diferença entre os grupos de armazenamento, com similares valores de rugosidade, enquanto os outros materiais apresentaram maiores valores após a biodegradação. Quando a degradação foi cumulativa (biomecânica), Ketac N100 obteve os menores valores de rugosidade. Microscopicamente foi observado um aspecto corroído na matriz biodegradada e a exposição das partículas na superfície dos materiais após os seguidos desafios. Portanto, a incorporação da nanotecnologia ao nano-ionômero auxiliou na obtenção de resistência à degradação biomecânica superior aos outros materiais estudados. Entretanto, suas propriedades químicas anti-cariogênicas foram negativamente influenciadas e consideradas inferiores ao Vitremer Abstract: The direct interaction between restoration and dental biofilm frequently occurs in the oral cavity. Its consequences are related to physico-chemical characteristics of the restorative material and to virulence of the bacteria adhered. The aim of this study was to evaluate different restorative glass ionomer cements subjected to biodegradation by Streptococcus mutans biofilm and to brushing abrasion in vitro. Each material studied (Ketac N100, Vitremer, Ketac Molar Easymix e Fuji IX) was tested as recently handled mix or as set discs, prepared under aseptic conditions. At that condition, the material was inserted into wells for agar diffusion test and analysis of growth inhibition zones of S. mutans UA159 (n=8), while the discs were distributed in different tests: a) two-hours adherence test of this strain on those ionomeric materials, by counting the colony-forming units (n = 10); b) tests related to bacterial accumulation for seven days (n = 10) - biofilm wet weight, pH of growth medium every 48 hours (medium renewal) and fluoride released in that same medium. After seven days of biodegradation, the discs were washed and evaluated about surface roughness (Ra) and micromorphology. As control group, ten discs were kept in relative humidity for the same period. Then, toothbrush abrasion test (mechanical degradation) was performed, and specimens were reevaluated. Data from inhibition zones, S. mutans adherence and wet weight of biofilm were submitted to Kruskal-Wallis and Mann-Whitney tests. ANOVA and Tukey tests were applied to fluoride-released, pH and roughness data. The level of significance was set at 5%. There was no statistically significant difference among the materials regarding the initial adherence (p = 0.6272) and final biofilm weight (p = 0.9612). Vitremer showed the largest inhibitory zones, higher pH values than Ketac N100 and Fuji IX at the first exchange medium (48h), and higher fluoride release than Ketac N100 e Ketac Molar Easymix throughout the experimental period. Ketac N100 showed greater inhibitory zone than conventional ionomers and the lowest fluoride release, with a fall in values over time about twelve times. Concerning surface roughness, there was significant interaction among factors: material, storage (humidity/biofilm) and abrasion (before/after). Vitremer showed similar Ra values between storage groups, while other materials presented higher Ra values after biodegradation test. Concerning cumulative biomechanical challenge, Ketac N100 presented the lowest Ra values. The corroded aspect after biodegradation and the exposition of fillers after mechanical degradation were visualized at micrographs. Therefore, the nanotechnology incorporation in the nano-ionomer promoted better resistance to biomechanical degradation than other materials studied. However, its anticariogenic chemical properties were negatively influenced and considered inferior to Vitremer Doutorado Materiais Dentários Doutor em Materiais Dentários
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- 2021
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22. Affinity of Staphylococcus aureus for prostheses colonization compared to other bacteria. An in vitro study
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Mariângela Esther Alencar Marques, Mércia de Carvalho Almeida, Isadora Delfino Caldeira, Bruno Carvalho Henriques, Cesar Alberto Talavera Martelli, Gisele Alborghetti Nai, Fausto Viterbo de Oliveira Neto, Lizziane Kretli Winkelstroter Eller, Denis Aloísio Lopes Medina, Maria Júlia Schadeck Portelinha, and Mayla Silva Cayres de Oliveira
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Implante mamario ,medicine.medical_treatment ,Procedimientos quirúrgicos vasculares ,Breast implant ,medicine.disease_cause ,Procedimentos cirúrgicos vasculares ,Prosthesis ,Enterococcus faecalis ,Microbiology ,Staphylococcus epidermidis ,Biopelículas ,Prostheses and implants ,medicine ,Politetrafluoroetileno ,Próteses e implantes ,Escherichia coli ,Polytetrafluoroethylene ,General Environmental Science ,biology ,Chemistry ,Biofilm ,biology.organism_classification ,Proteus mirabilis ,Prótesis e implantes ,Implantes mamários ,Staphylococcus aureus ,Biofilms ,Vascular surgical procedures ,General Earth and Planetary Sciences ,Bacteria ,Biofilmes - Abstract
Staphylococcus aureus biofilms have been recognized as a leading cause of multiple infections, including implant-associated infections and chronic wounds. We evaluated the colonization capacity of two distinct textured prostheses by different bacterial strains. Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Proteus mirabilis and Enterococcus faecalis were evaluated. Initially, the hydrophobicity and biofilm formation capacity were determined. Subsequently, 20 fragments of vascular prosthesis and 20 silicone prostheses were embedded in suspensions with the microorganisms and incubated. The prostheses were then sown in culture medium and incubated for 48 hours. Petri dishes were photographed and analyzed by fractal dimension. The Kruskal-Wallis test and the Dunn test were applied for the analysis of biofilm formation. To compare the mean intensity for the type of bacteria and the type of prosthesis, a general linear model was applied. Staphylococcus aureus was the bacterium with the highest colonization density in both prostheses (p = 0.0001). E. coli showed strong adherence in the biofilm formation capacity test (p = 0.0001), however, it did not colonize either prosthesis. We demonstrated that Staphylococcus aureus has a greater affinity for vascular and silicone prostheses than other bacteria. Se ha reconocido que las biopelículas de Staphylococcus aureus son una de las principales causas de infecciones múltiples, incluidas las infecciones asociadas a implantes y las heridas crónicas. Evaluamos la capacidad de colonización de dos prótesis texturizadas distintas por diferentes cepas bacterianas. Se evaluaron Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Proteus mirabilis y Enterococcus faecalis. Inicialmente se determinó la hidrofobicidad y la capacidad de formación de biopelículas. Posteriormente, se embebieron 20 fragmentos de prótesis vasculares y 20 prótesis de silicona en suspensiones con los microorganismos y se incubaron. A continuación, las prótesis se sembraron en medio de cultivo y se incubaron durante 48 horas. Las placas de Petri se fotografiaron y analizaron por dimensión fractal. Se aplicaron la prueba de Kruskal-Wallis y la prueba de Dunn para el análisis de la formación de biopelículas. Para comparar la intensidad media para el tipo de bacteria y el tipo de prótesis, se aplicó un modelo lineal general. Staphylococcus aureus fue la bacteria con mayor densidad de colonización en ambas prótesis (p = 0,0001). Escherichia coli mostró una fuerte adherencia en la prueba de capacidad de formación de biopelículas (p = 0,0001), sin embargo, no colonizó ninguna de las prótesis. Demostramos que Staphylococcus aureus tiene una mayor afinidad por las prótesis vasculares y de silicona que otras bacterias. Biofilmes de Staphylococcus aureus foram reconhecidos como uma das principais causas de infecções múltiplas, incluindo infecções associadas a implantes e feridas crônicas. Avaliamos a capacidade de colonização de duas próteses texturizadas distintas por diferentes cepas bacterianas. Foram avaliados Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Proteus mirabilis e Enterococcus faecalis. Inicialmente, foram determinadas a hidrofobicidade e a capacidade de formação de biofilme. Posteriormente, 20 fragmentos de próteses vasculares e 20 próteses de silicone foram incluídos em suspensões com os microrganismos e incubados. As próteses foram então semeadas em meio de cultura e incubadas por 48 horas. As placas de Petri foram fotografadas e analisadas pela dimensão fractal. O teste de Kruskal-Wallis e o teste de Dunn foram aplicados para a análise da formação de biofilme. Para comparar a intensidade média para o tipo de bactéria e o tipo de prótese, foi aplicado um modelo linear geral. Staphylococcus aureus foi a bactéria com maior densidade de colonização em ambas as próteses (p = 0,0001). Escherichia coli apresentou forte aderência no teste de capacidade de formação de biofilme (p = 0,0001), porém não colonizou nenhuma das próteses. Demonstramos que o Staphylococcus aureus tem maior afinidade por próteses vasculares e de silicone do que outras bactérias.
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- 2021
23. Influencia de caracteristicas fisicas e quimicas de plastificantes na confecção e no comportamento estrutural e higroscopico de filmes de alginato de calcio
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Santana, Audirene Amorim, Kieckbusch, Theo Guenter, 1942-2021, Grosso, Carlos Raimundo Ferreira, Collares, Fernanda de Paula, Universidade Estadual de Campinas. Faculdade de Engenharia Química, Programa de Pós-Graduação em Engenharia Química, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Poliois ,Biofilm ,Alginate ,Plasticizer ,Alginato de calcio ,Polyols ,Plastificante ,Transição vítrea ,Glass transition ,Biofilmes - Abstract
Orientador: Theo Guenter Kieckbusch Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica Resumo: O consumidor consciente tem dado preferência a alimentos processados de melhor qualidade nutricional e com vida de prateleira prolongada, sempre com a devida preocupação com os efeitos prejudiciais acumulativos ao meio ambiente do descarte de subprodutos. Filmes biodegradáveis estão inseridos neste contexto. Eles são produzidos a partir de polímeros naturais, principalmente polissacarídeos e proteínas, com potencial aplicação na indústria farmacêutica e alimentícia. O alginato é um polissacarídeo que tem extensa aplicação em biotecnologia devido a sua habilidade de formar géis fortes e insolúveis ao ser reticulado com Ca++. Essa reação é tão rápida e localizada, impedindo a posterior moldagem do gel em forma de filmes. Para a confecção de filmes insolúveis é necessário primeiro fabricar um filme de alginato de sódio de baixa reticulação com cálcio, já contendo plastificante, que é então exposto a uma solução contendo cálcio para completar a reticulação por difusão. Nesse contato, entretanto, a solução reticuladora pode solubilizar o plastificante e o filme formado não apresenta uma flexibilidade desejável. Assim, o objetivo deste estudo foi selecionar formulações para a confecção de filmes de alginato de cálcio estruturados com plastificantes que apresentem baixa tendência de lixiviação/solubilização em meios aquosos. O estudo enfocou primeiramente plastificantes convencionais (glicerol, manitol, xilitol, sorbitol, maltitol e poli-etileno glicol-300). Também foram considerados os açúcares simples (frutose, lactose e sacarose), ácido graxo de cadeia curta (ácido hexanóico), surfactante não-iônico (Tween 20) e solutos não-convencionais (etanolamina, lactato de sódio, triacetina e citrato de tributila). Apenas formulações que produziam filmes transparentes de boa manuseabilidade foram consideradas, e esse critério eliminou os filmes plastificados com poli-etileno glicol-300, maltitol, lactose, sacarose, frutose, etanolamina, lactato de sódio, Tween 20, triacetina e ácido hexanóico. A seleção definitiva de plastificantes considerou, o aspecto visual, conteúdo de umidade, solubilidade em água, permeabilidade ao vapor de água, grau de intumescimento, resistência à tração e alongamento dos filmes formados. Os plastificantes que produziram filmes que satisfizeram requisitos mínimos para esses atributos foram glicerol, xilitol, manitol e citrato de tributila. Filmes com esses plastificantes foram submetidos à determinação de observações microscópicas de sua estrutura (MEV) e de isotermas de sorção, cor e opacidade e temperatura de transição vítrea. Os resultados confirmaram a excelente ação plastificante do glicerol e um comportamento similar do xilitol. O manitol e o citrato de tributila formam filmes de baixa higroscopicidade, mas são pouco flexíveis. Um compromisso entre alta resistência mecânica, boa aparência e baixa solubilidade em água pode ser obtido usando uma mistura de citrato de tributila e glicerol Abstract: Responsible consumers are looking for processed food with higher nutritional value and extended shelf live, without disregarding the damaging cumulative effects of sub products discharge on the environment. Biodegradable films are part of this concept. They are produced from natural polymers, mainly saccharides and proteins, with potential applications in the pharmaceutical or food industries. Alginates are polysaccharides with large applications in biotechnology due to their ability to form strong and insoluble gels when crosslinked with Ca++. This reaction is fast and localized, preventing subsequent casting of the gel in the form of a film. In order to produce smooth and insoluble films, a weekly reticulated film already containing the plasticizer is confectioned first, and then exposed to a calcium solution and the reticulation is complemented by diffusion. During the contact period, however, the solution is prone to leach the plasticizer, and the resulting film will not present the required flexibility. The objective of this study was to select calcium alginate film forming formulations structured with plasticizers that show low solubilization/leaching susceptibilities in aqueous environments. The study examined initially the more conventional plasticizers (glycerol, mannitol, xylitol, sorbitol maltitiol, polyethylene glycol (PEG 300)). Consideration was then given to the simpler sugars (like fructose, lactose and sucrose), short chain fatty acids (hexanoico acid), non ionic surfactant (Tween 20) and non conventional solutes like ethanolamine, sodium lactate, triacetin and tributyl citrate. The final selection of adequate plasticizers was based on visual aspect, moisture content, solubility in water, water vapor permeability, degree of swelling in water, tensile strength and elongation of the films. The plasticizers that produced films with an adequate compromise within these attributes were glycerol, xylitol, mannitol and tributyl citrate. Films containing these plasticizers were submitted to microscopic observations of their structure (MEV), and their sorption isotherms, color and transparency, and glass transition temperature were determined. The results confirmed the excellent and powerful plasticizing effect of glycerol and a similar behavior of xylitol. Mannitol and tributyl citrate form films with lower hygroscopicity, but are less flexible. A compromise between high mechanical resistance, attractive appearance and low solubility in water can be obtained with a mixture of tributyl citrate and glycerol Mestrado Engenharia de Processos Mestre em Engenharia Química
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- 2021
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24. Dentifricio de baixa concentração de fluoreto
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Zamataro, Claudia Bianchi, Tenuta, Livia Maria Andaló, 1976, Araujo, Fernando Borba de, Nobre dos Santos, Marinês, Universidade Estadual de Campinas. Faculdade de Odontologia de Piracicaba, Programa de Pós-Graduação em Odontologia, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Bioquímica ,Biofilm ,Biochemistry ,Biofilmes - Abstract
Orientador: Livia Maria Andalo Tenuta Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba Resumo: A eficiência anticárie dos dentifrícios fluoretados contendo 1000-1500 µg F/g está bem estabelecida, porém eles têm sido considerados fator de risco para fluorose dental. Para reduzir esse risco, dentifrícios contendo baixa concentração de fluoreto (F) (500-550 µg F/g) têm sido recomendados, mas sua eficiência anticárie ainda não foi demonstrada. Assim, o objetivo deste trabalho foi: 1. comparar a disponibilidade de F na saliva após utilização de dentifrício de baixa concentração de F (BC, 500 µg F/g, NaF), ou dentifrício de concentração convencional (CC, 1100 µg F/g, NaF), seguida ou não de enxágüe; e 2: avaliar in situ o potencial anticariogênico desses dentifrícios, estudando o efeito do F disponível no biofilme dental após a escovação, associado ou não aos produtos formados no esmalte pelo tratamento com os dentifrícios. Em ambos os estudos, foi empregado um delineamento cruzado e duplo cego. No estudo 1, amostras de saliva não estimulada de 5 voluntários foram coletadas antes e imediatamente após a escovação e nos tempos 1, 2, 3, 4, 5, 10, 15, 20, 30, 45 e 60 min após a escovação com BC ou CC, seguida ou não de enxágüe. A área sob a curva da concentração de F na saliva versus tempo foi calculada para determinar a biodisponibilidade de F salivar. Esta foi reduzida em 2,5 x pelo enxágüe pósescovação (p0,05). No estudo 2, doze voluntários realizaram escovação com dentifrícios contendo concentrações de F distintas (placebo (P) ¿ controle negativo, CC ou BC) e utilizaram um dispositivo palatino contendo blocos de esmalte bovino, previamente tratados ou não com suspensão do respectivo dentifrício. Os blocos foram cobertos com uma placa teste de S. mutans IB 1600 e após 30 min in situ, a placa foi coletada e a concentração de F no fluido foi determinada através de técnica microanalítica com eletrodo íon específico. Um bochecho com sacarose foi realizado como desafio cariogênico e após 45 min os blocos remanescentes e a placa teste foram coletados para avaliação, respectivamente, da perda mineral (simulando o efeito de diferentes espessuras de placa) e da concentração de F no fluido. O pré-tratamento dos blocos de esmalte com os dentifrícios fluoretados isoladamente não impediu a perda mineral em relação ao controle (p>0,05), mas causou aumento na concentração de F no fluido da placa (p0.05). In study 2, twelve volunteers brushed with dentifrices containing distinct F concentrations (placebo (P) ¿ negative control, LC or CC) and used a palatal appliance containing bovine enamel blocks previously treated or not with a slurry of assigned dentifrice. The blocks were covered with a test plaque from S. mutans IB 1600 and after 30 min in situ, F concentration in the fluid of plaque was assessed. A sucrose rinse was performed as a cariogenic challenge and after 45 min the remaining blocks and plaque test were removed to evaluate, respectively, mineral loss (as a function of plaque thickness) and F concentration in plaque fluid. The isolated effect of the pretreatment of enamel blocks with F dentifrices did not reduced mineral loss when compared to the control (p>0.05), but resulted in higher F concentration in the plaque fluid (p
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- 2021
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25. Biofilmes monoespécie e multiespécies de patógenos gram-positivos de origem láctea em diferentes substratos
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Alonso, Vanessa Pereira Perez, 1979, Kabuki, Dirce Yorika, 1964, Fernandes, Meg da Silva, Junqueira, Valeria Christina Amstalden, Universidade Estadual de Campinas. Faculdade de Engenharia de Alimentos, Programa de Pós-Graduação em Ciência de Alimentos, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Staphylococcus aureus ,Bacillus cereus ,Biofilm ,Enterococcus faecalis ,Listeria monocytogenes ,Biofilmes ,Estafilococos aureos - Abstract
Orientador: Dirce Yorika Kabuki Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Resumo: Patógenos causadores de Doenças transmitidas por alimentos (DTAs), frequentemente são encontrados em produtos lácteos e preocupam a indústria de alimentos por sua capacidade de formação de biofilme em superfícies de aço inoxidável. Bacillus cereus, Enterococcus faecalis, Listeria monocytogenes e Staphylococcus aureus são patógenos Gram positivos encontrados em produtos lácteos e, neste estudo, a capacidade de formação de biofilme monoespécie e multiespécies em superfície de aço inoxidável a 25ºC em diferentes substratos foram avaliadas. A formação de biofilmes foi verificada pela técnica da contagem em placas nos tempos 6h, 24h, 48h, 96h, 168h e 220h. Os cupons de aço inoxidável (AISI 304) foram colocados em diferentes substratos, caldo infusão de cerebro e coração (BHI), soro de leite e leite desnatado, inoculados com aproximadamente 103 UFC/ml de patógenos de origem láctea. Os micro-organismos avaliados foram capazes de formar biofilmes monoespécie e multiespécies, com contagens de até 7 log UFC/cm2. Foi observado maior esporulação do B. cereus em caldo BHI e leite desnatado, quando comparado com soro de leite. E. faecalis apresentou maior crescimento quando em biofilme multiespécies e quando em monoespécie maior equilíbrio entre os diferentes substratos. Por outro lado, S. aureus, B. cereus e L. monocytogenes quando em biofilme multiespécies no soro de leite, apresentaram pouco crescimento, sendo que L. monocytogenes apresentou o mesmo padrão de comportamento também no leite desnatado Abstract: Pathogens that cause food-borne diseases are often found in dairy products and are concerned about the food industry for their ability to form biofilm on surfaces of stainless steel. Bacillus cereus, Enterococcus faecalis, Listeria monocytogenes and Staphylococcus aureus are pathogens Gram-positive found in milk products and, in this study, the ability to form biofilm highly industrialized and single-species fishing and multi-species in stainless steel surface at 25C in different substrates were evaluated.The formation of biofilms was verified by the technique of counting cards in time 6h, 24h, 48h, 96h, 168h and 220H. The coupons of stainless steel (AISI 304) were placed in different substrates, broth brain heart infusion (BHI), whey and skimmed milk, inoculated with approximately 103 CFU/ml of pathogens of dairy origin. The microorganism, were capable of forming biofilms highly industrialized and single-species fishing and multi-species, with counts of up to 7 log CFU/cm2. There was a higher sporulation of B. cereus in BHI broth and skimmed milk, when compared with whey. E. faecalis showed greater growth when in multi-species biofilm and when in highly industrialised and single-species fishing greater balance between the different substrates. Moreover a reduction of S. aureus, B. cereus and L. monocytogenes was observed in the presence of the in multi-species biofilm in whey, showed little growth, and L. monocytogenes presented the same pattern of behavior also in skimmed milk Mestrado Ciência de Alimentos Mestra em Ciência de Alimentos CAPES
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- 2021
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26. Caracterização de três fatores de transcrição pertencentes à família LysR de Xylella fastidiosa
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Pelloso, Alexandre César, 1983, Souza, Anete Pereira de, 1962, Aparicio, Ricardo, 1971, Venancio, Emerson José, Dias, Sandra Martha Gomes, Universidade Estadual de Campinas. Instituto de Biologia, Programa de Pós-Graduação em Genética e Biologia Molecular, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Biofilm ,Blotting, Western ,Small-angle X-ray scattering ,Xylella fastidiosa - Pathogenicity ,Xylella fastidiosa - Patogenicidade ,Raios X - Espalhamento a baixo ângulo ,Biofilmes ,Western blotting - Abstract
Orientadores: Anete Pereira de Souza, Ricardo Aparício Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia Resumo: Após o sequenciamento do genoma da Xylella fastidiosa, linhagem 9a5c houve um grande aumento de informações relacionadas a este organismo. Porém grande parte das proteínas desta bactéria ainda não apresentam funções preditas. No presente estudo, objetivou-se a caracterização inicial de três proteínas deste micro-organismo, a saber: XfCysB (orf Xf0683), XfLysRL (orf Xf1448) e XfycjZ (orf Xf1480). Essas proteínas apresentam alta similaridade com membros da família de reguladores transcricionais do tipo LysR (LTTR). Os LTTR constituem a família de reguladores mais comuns em procariotos e apresentam funções diversas tais como regulação de genes envolvidos no metabolismo, divisão celular, quorum sense, virulência, resposta ao estresse oxidativo, entre outras. Dentre as proteínas em estudo, a única proteína que possui predição dentro da família LysR é a XfCysB, cujas proteínas homólogas, já caracterizadas, estão envolvidas na regulação do operon cys, o qual está envolvido na biossíntese de cisteína. Após a clonagem das proteínas, a caracterização estrutural foi feita por Cromatografia de Exclusão por Peso Molecular, em que foi possível observar o estado oligomérico da proteína; Dicroísmo Circular para verificar se a proteína apresenta estrutura secundária estruturada e SAXS (Espalhamento de Raios-X a Baixos Ângulos) ,apenas para a proteína XfLysRL, para a determinação do envelope da proteína em solução. A caracterização funcional foi feita pela análise da expressão das proteínas durante as diferentes fases de formação do biofilme (5, 10, 15, 20 e 30 dias de crescimento) de X. fastidiosa por Western blot utilizando anticorpos específicos para cada proteína em estudo. Com os resultados obtidos pode-se estimar que a massa molecular da proteína XfLysRL é de 50 kDa quando em solução, indicando que a XfLysRL encontra-se na forma dimérica, uma vez que a massa molecular do monômero é de 23,7 kDa. Possui também a estrutura secundária estruturada, sendo estável de 4°C a 44 ° C. Foi possível verificar também que a proteína está monodispersa quando em solução, é estruturalmente globular e pôde-se produzir, com os dados obtidos, um primeiro modelo para a estrutura da proteína. Já a proteína XfCysB teve a sua massa estimada em 45,3 kDa quando em solução e de 195,1 kDa quando na presença do seu co-indutor específico, além de apresentar uma estrutura secundária estruturada. Em relação à proteína XfycjZ pôde-se observar que esta quando em solução possui uma massa molecular estimada em 174,8 kDa demonstrando que sua forma oligomérica é de tetrâmero. Os estudos funcionais indicam que as três proteínas são expressas durante a formação do biofilme de X. fastidiosa, ou seja, estão presentes nos 6 tempos analisados. Deste modo, o estudo detalhado das presentes proteínas torna-se importante devido a sua presença na formação do biofilme de X. fastidiosa, um dos mecanismos de patogenicidade da bactéria. Outro fator importante é a utilização dos resultados da caracterização estrutural na elucidação do papel desempenhado pelas proteínas, visto que a estrutura protéica está diretamente envolvida com sua função Abstract: After sequencing the genome of Xylella fastidiosa, strain 9a5c, there was a large increase in information related to this organism, but most of the proteins produced by these bacteria do not have predicted functions. In this study, the objective was the initial characterization of three proteins of this organism, namely XfCysB (orf Xf0683) XfLysRL (orf Xf1448) and XfycjZ (orf Xf1480). These proteins show high similarity to members of the family of LysR-type transcriptional regulators (LTTR). The LTTR family of regulators is the most common in prokaryotes and has diverse functions such as regulation of genes involved in metabolism, cell division, quorum sense, virulence, oxidative stress response, among others. Among the proteins under study, the only protein that has more specific prediction of classification within the family is the LysR XfCysB, which already characterized homologous proteins are involved in the regulation of cys operon, which is involved in the biosynthesis of cysteine. After cloning the protein, structural characterization was performed using the techniques of Exclusion Chromatography for Molecular Weight that shows the oligomeric state of the protein; circular dichroism to determine if protein has folded and stable secondary structure and SAXS (X-Ray Scattering at Small Angle) for the determination of protein structure in solution. Functional characterization was performed by analyzing the expression of proteins during different stages of biofilm formation (5, 10, 15, 20 and 30 days of growth) of X. fastidiosa by producing antibodies specific for each protein under study and performance of Western blot using total protein extract of the antibody produced against biofilm. With results obtained it was possible to estimate that the molecular weight of protein was 50 kDa XfLysRL in solution, indicating that the XfLysRL is in dimeric form, since the molecular weight of the monomer is 23.7 kDa. It also has a stable secondary structure folded and supporting a rise in temperature to 44° C. It was also verified that the protein is monodisperse in solution, is structurally globular and could be produced, with the data obtained, a first model for the structure of the protein. The protein XfCysB had its mass estimated at 45.3 kDa in solution and 195.1 kDa in the presence of its coinducer specific, besides presents a folded secondary structure. Regarding the protein XfycjZ was observed that when this solution has a molecular mass of 174.8 kDa demonstrating that it's oligomeric form is a tetramer. Functional studies indicate that the three proteins were expressed during the biofilm formation of X. fastidiosa, follows that they are present in 6 times analyzed. Thus, the detailed study of these proteins is important because their presence in biofilm formation of X. fastidiosa, one of the mechanisms of pathogenicity of the bacteria. Another important factor is the use of results in the structural elucidation of the role of proteins because the protein structure is directly involved in its function Mestrado Genética Vegetal e Melhoramento Mestre em Genética e Biologia Molecular
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- 2021
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27. Evaluation of sulfamethoxazole removal by biologic treatment and photodegradation by UV-LED
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Barbosa, Ariane Corrêa, 1986, Tonetti, Adriano Luiz, 1973, Guimarães, José Roberto, Aquino, Sérgio Francisco de, Paz, Lyda Patrícia Sabogal, Fadini, Pedro Sérgio, Universidade Estadual de Campinas. Faculdade de Engenharia Civil, Arquitetura e Urbanismo, Programa de Pós-Graduação em Engenharia Civil, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Remoção de contaminantes emergentes ,Biofilm ,Photodegradation ,Emerging pollutants removal ,Fotodegradação ,Biological treatment ,Biofilmes ,Tratamento biológico - Abstract
Orientador: Adriano Luiz Tonetti Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo Resumo: A presença de antimicrobianos no solo e corpos d'água pode promover e disseminar genes e bactérias resistentes. A adoção de sistemas de tratamento descentralizados, mesmo quando as águas residuais geradas são destinadas à Estações de Tratamento de Esgoto (ETE), é uma alternativa para mitigar a contaminação pelos contaminantes emergentes. Por isso, o entendimento da remoção dos antimicrobianos em diferentes técnicas de tratamento deve ser buscado. Nesse contexto, o presente estudo avaliou a remoção do sulfametoxazol (SMX) em diferentes técnicas de tratamento de efluentes que, quando combinados, podem gerar água para reúso. Na primeira etapa do estudo foi aplicado efluente sintético nos seguintes reatores biológicos: Reator Anaeróbio de Leito Fixo (RALF), Filtro Biológico Percolador (FBP) e Filtro de Areia (FA). O RALF apresentou eficiência de remoção entre 0 e 45%. O FBP e FA proporcionaram um melhor desempenho na remoção do SMX atingindo valores máximos de remoção global de 80%. Nessa etapa também foi avaliado o desempenho do RALF quando exposto à diferentes concentrações de SMX (0, 10 e 50 µg L-1. Foi verificado uma redução significativa na eficiência de remoção da matéria orgânica quando aplicado o efluente sintético enriquecido com 50 µg L-1 de SMX. Na segunda etapa, aplicando efluente bruto em FBP e FA de construção similar da etapa anterior e em vermifiltros, avaliou-se a remoção do SMX. Contudo, não foi observado a remoção desse antimicrobiano em nenhum dos reatores supracitados. Na terceira etapa do estudo, a fim de avaliar o uso de processos físico-químicos para o polimento do efluente doméstico tratado por reatores biológicos, foram estudadas duas técnicas de fotodegradação: fotólise e peroxidação assistida por UV usando lâmpadas LED (UV-LED-H2O2). Somente a fotólise não foi suficiente para a degradação do sulfametoxazol em uma solução a 800 µg L-1 em água ultrapura. Quando aplicado o processo UV-LED-H2O2 resultou na degradação média de 80% desse antimicrobiano. Os resultados obtidos nesse estudo evidenciam a necessidade em melhorar as técnicas de tratamento biológico e aplicar técnicas de fotodegradação a fim de remover o SMX Abstract: The presence of antimicrobials in aquatic environments and soil is a significant means of the spread of genes and antibiotic-resistant bacteria. Implementing decentralized treatment is recommended to mitigate the release of antimicrobials into water bodies, even when wastewater is discharged into the municipal sewer system. Therefore, it is pivotal to understand the efficiency of different wastewater treatment technologies at removing antimicrobial compounds both onsite and offsite. In this context, this study investigated the removal efficiency of Sulfamethoxazole (SMX) in different reactors of wastewater treatment that, when combined, provide reusable water. In the first stage, synthetic domestic wastewater was applied in the following biological reactors: Anaerobic Packed Bed Reactor (APBR), Trickling Filter (TF), and Sand Filter (SF). The APBR removed up to 45% of SMX while better performance was obtained by the TF and SF, which attained the highest removal of 80\%. In this phase, the influence of the SMX concentration (0, 10, and 50 µg L-1) on the APBR performance was also evaluated. A significant reduction in the removal efficiency of organic matter was verified when the synthetic effluent enriched with 50 µg L-1 of SMX was applied. In the second stage, the removal efficiency of SMX in real domestic wastewater was evaluated in the TF and SF of similar configurations as in the previous step and Vemifilter (VF). However, the results showed no noticeable reduction of SMX by these reactors. In the third stage, the use of physicochemical processes to assist the treatment of domestic effluents by biological reactors was studied. The SMX degradation was studied employing photolysis (UV) and ultraviolet radiation-assisted peroxidation using a light-emitting diode (UV-LED-H2O2). Photolysis alone was ineffective in the removal of SMX at the concentration of 800 µg L-1 in ultra-pure water. Nonetheless, the photodegradation process was improved with the addition of hydrogen peroxide (UV-LED-H2O2, attaining a removal efficiency of SMX of 80%.The results obtained in this study high light the need to improve biological treatments and apply photodegradation techniques to remove SMX Doutorado Saneamento e Ambiente Doutora em Engenharia Civil CAPES 88882.435132/2019-01 FAPESP 2017/07490-4
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- 2021
28. Use of wide-field optical fluorescence for visualization of oral biofilm in a patient with peri-implant mucositis: a new approach
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Sérgio Araújo Andrade, Sebastião Pratavieira, Vanderlei Salvador Bagnato, and Fernando de Pilla Varotti
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Mucositis ,Peri-implant mucositis ,medicine.medical_treatment ,Dentistry ,Case Report ,Gram-negative anaerobic bacteria ,03 medical and health sciences ,0302 clinical medicine ,Diagnosis, oral ,medicine ,030212 general & internal medicine ,Dental implant ,Mucosite ,Implantação dentária ,Dental implantation ,business.industry ,Biofilm ,Soft tissue ,Relato de Caso ,General Medicine ,medicine.disease ,Wide field ,Optical fluorescence ,Diagnóstico bucal ,Bactérias anaeróbias Gram-negativas ,Biofilms ,030220 oncology & carcinogenesis ,Medicine ,Implant ,business ,Biofilmes - Abstract
Peri-implant diseases, caused by bacteria from biofilm related to dental implants, are one of the main causes of late loss of implants. In this sense, peri-implant diseases are divided into peri-implant mucositis, when it affects only the soft tissues, and peri-implantitis, when there is a bone involvement, which can lead to the failure of dental implant therapy. Thus, biofilm removal is essential for peri-implant health, allowing long-term success in implant therapy. To improve the visualization of oral biofilm, which is usually transparent or colorless, disclosing agents have been routinely used. However, disclosing agents have allergenic potential and can cause staining extrinsically in restorative and prosthetic materials, leading to aesthetic impairment. Thus, the use of fluorescence has been studied as an alternative for visualization of oral biofilm. Therefore, this report describes the use of wide-field optical fluorescence for visualization of oral biofilm associated with implants and teeth, in a routine appointment and follow-up of a partially edentulous patient with peri-implant mucositis. In addition, this report showed wide-field optical fluorescence can be used in a clinical routine of care of patients with dental implants. In this sense, wide-field optical fluorescence allowed easy and immediate visualization of the mature oral biofilm for its adequate removal, evaluation of the quality of restoration to sealing of screw access-hole of implant and identification of cariogenic lesions, without risk of allergic reactions or staining of prostheses and restorations.
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- 2021
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29. Editorial : Developing bioactive materials for dental applications
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Mary Anne Melo, Fabricio Collares, Salvatore Sauro, UCH. Departamento de Odontología, and Producción Científica UCH 2021
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bioactive ,Technology ,Engineering ,Biomedical materials ,business.industry ,Materials Science (miscellaneous) ,nanotecehnology ,biomaterial ,Biofilm ,Biomaterial ,Nanotechnology ,Nanotecnología ,biofilm ,Adhesivos dentales ,Dental adhesives ,Biofilms ,Biofilmes ,dental (restorative) composites ,Materiales biomédicos ,business - Abstract
Este artículo se encuentra disponible en la siguiente URL: https://www.frontiersin.org/articles/10.3389/fmats.2021.751618/full
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- 2021
30. Influence of caries activity and number of saliva donors: mineral and microbiological responses in a microcosm biofilm model
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Françoise Hélène van de Sande, Cácia Signori, Tamires Timm Maske, Elenara Ferreira de Oliveira, Maximiliano Sérgio Cenci, and Chayane Souza Viana
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Saliva ,Microcosm ,Dental Caries Susceptibility ,Demineralization ,Streptococcus mutans ,Humans ,Food science ,General Dentistry ,Minerals ,Enamel paint ,Chemistry ,Biofilm ,Cárie dentária ,RK1-715 ,Caries activity ,visual_art ,Biofilms ,Desmineralização do dente ,Dentistry ,visual_art.visual_art_medium ,Dental caries ,Original Article ,Biofilmes - Abstract
Objective this study evaluated the mineral and microbiological response of biofilms originating from different types of saliva inoculum with distinct levels of caries activity. Methodology the biofilms grown over enamel specimens originated from saliva collected from a single donor or five donors with two distinct levels of caries activity (caries-active and caries-free) or from pooling saliva from ten donors (five caries-active and five caries-free). The percentage surface hardness change (%SHC) and microbiological counts served as outcome variables. Results the caries activity of donors did not affect the %SHC values. Inoculum from five donors compared to a single donor showed higher %SHC values (p=0.019). Higher lactobacilli counts were observed when saliva from caries-active donors was used as the inoculum (p=0.017). Pooled saliva from both caries activity levels showed higher mutans streptococci counts (p
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- 2021
31. Pseudonajide peptide derived from snake venom alters cell envelope integrity interfering on biofilm formation in Staphylococcus epidermidis
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Sylvie Nonin-Lecomte, Reynald Gillet, Muriel Primon-Barros, Rafael Gomes Von Borowski, Sophie Chat, Alexandre José Macedo, Rafael de Oliveira Schneider, Institut de Génétique et Développement de Rennes (IGDR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ), Universidade Federal do Rio Grande do Sul [Porto Alegre] (UFRGS), Cibles Thérapeutiques et conception de médicaments (CiTCoM - UMR 8038), Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Brazilian Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)CAPES [001], Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)National Council for Scientific and Technological Development (CNPq), Fundacao de Amparo a Pesquisa do Estado do Rio Grande do Sul (FAPERGS-PRONEN), French Centre National de Recherche Scientifique (CNRS)Centre National de la Recherche Scientifique (CNRS), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique )-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), and Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)
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Microbiology (medical) ,Pseudonajide ,Hepcidinas ,Venenos de serpentes ,Cell Survival ,Amino Acid Motifs ,Antimicrobial peptides ,lcsh:QR1-502 ,Gene Expression ,Peptide ,[CHIM.THER]Chemical Sciences/Medicinal Chemistry ,Biology ,Microbiology ,Permeability ,Bacterial cell structure ,lcsh:Microbiology ,biofilm ,Cell Line ,03 medical and health sciences ,Cell Wall ,Staphylococcus epidermidis ,Animals ,Humans ,030304 developmental biology ,snake venom ,chemistry.chemical_classification ,0303 health sciences ,030306 microbiology ,Cell Membrane ,Biofilm ,Antimicrobial ,biology.organism_classification ,[SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology ,Anti-Bacterial Agents ,3. Good health ,Teichoic Acids ,chemistry ,Snake venom ,pseudonajide ,Biofilms ,Cell envelope ,Antimicrobial peptide ,Biofilmes ,Antimicrobial Cationic Peptides ,Snake Venoms ,Research Article - Abstract
Background The increase in bacterial resistance phenotype cases is a global health problem. New strategies must be explored by the scientific community in order to create new treatment alternatives. Animal venoms are a good source for antimicrobial peptides (AMPs), which are excellent candidates for new antimicrobial drug development. Cathelicidin-related antimicrobial peptides (CRAMPs) from snake venoms have been studied as a model for the design of new antimicrobial pharmaceuticals against bacterial infections. Results In this study we present an 11 amino acid-long peptide, named pseudonajide, which is derived from a Pseudonaja textilis venom peptide and has antimicrobial and antibiofilm activity against Staphylococcus epidermidis. Pseudonajide was selected based on the sequence alignments of various snake venom peptides that displayed activity against bacteria. Antibiofilm activity assays with pseudonajide concentrations ranging from 3.12 to 100 μM showed that the lowest concentration to inhibit biofilm formation was 25 μM. Microscopy analysis demonstrated that pseudonajide interacts with the bacterial cell envelope, disrupting the cell walls and membranes, leading to morphological defects in prokaryotes. Conclusions Our results suggest that pseudonajide’s positives charges interact with negatively charged cell wall components of S. epidermidis, leading to cell damage and inhibiting biofilm formation.
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- 2020
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32. Effect of calcium glycerophosphate, associated or not with fluoride, on the physiology, structure, matrix composition, cultivable cells, pH and on the concentrations of fluoride, calcium and phosphate of mixed biofilms of S. mutans and C. albicans
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Souza, Thamires Priscila Cavazana [UNESP], Universidade Estadual Paulista (Unesp), Delbem, Alberto Carlos Botazzo [UNESP], Pessan, Juliano Pelim [UNESP}, and Monteiro, Douglas Roberto [UNESP]
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Streptococcus mutans ,fluoride ,Candida albicans ,fosfato ,biofilmes ,flúor ,biofilm ,phosphate - Abstract
Submitted by Thamires Priscila Cavazana null (thamyk3cavazana@hotmail.com) on 2020-08-18T12:53:19Z No. of bitstreams: 1 Tese Final.pdf: 1391584 bytes, checksum: 365029cec810a745e1a3e265e7f41715 (MD5) Approved for entry into archive by Claudio Hideo Matsumoto null (claudio@foa.unesp.br) on 2020-08-18T17:47:39Z (GMT) No. of bitstreams: 1 souza_tpc_dr_araca_par.pdf: 308555 bytes, checksum: 7df37634c586760fb9f2bef4d2bc2729 (MD5) Made available in DSpace on 2020-08-18T17:47:39Z (GMT). No. of bitstreams: 1 souza_tpc_dr_araca_par.pdf: 308555 bytes, checksum: 7df37634c586760fb9f2bef4d2bc2729 (MD5) Previous issue date: 2020-07-24 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) O presente estudo teve como objetivo verificar o efeito do glicerofosfato de cálcio (CaGP), associado ou não ao fluoreto (F), na fisiologia, pH e componentes da biomassa e fluido de biofilmes mistos contendo Streptococcus mutans e Candida albicans, formados in vitro. Para formação dos biofilmes colocou-se uma suspenção (1×107 células/mL de C. albicans + 1×108 células/mL de S. mutans) em saliva artificial, suplementada com sacarose, em poços de placas de microtitulação. A cada 24 horas, metade do conteúdo da saliva artificial era renovado. Após os períodos de 72, 78 e 96 horas de formação, os biofilmes recebiam tratamentos, por um minuto, com soluções contendo CaGP (0.125, 0.25 ou 0.5%) com ou sem 500 ppm F, e soluções contendo somente F (500 e 1100 ppm F), adotadas como controles positivos, e saliva artificial, considerada como controle negativo. Para estudo da fisiologia microbiológica, após o terceiro tratamento foram realizados os testes de quantificação de células cultiváveis, biomassa total (teste colorimétrico de cristal violeta), atividade metabólica (redução de XTT), análise estrutural do biofilme (microscopia eletrônica de varredura) e quantificação dos componentes da matriz extracelular (proteína, carboidrato e DNA). Todos os ensaios foram realizados em triplicata, em três ocasiões diferentes. Os resultados foram submetidos à análise de variância a um critério, seguida pelo teste Fisher LSD (p
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- 2020
33. Impacto do tempo de contaminação por Escherichia coli na formação de biofilme em instrumentos cirúrgicos
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Simone Gonçalves dos Santos, Adriana Cristina de Oliveira, and Síntia de Souza Evangelista
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0301 basic medicine ,Microbiological culture ,Contaminação de Equipamentos ,RT1-120 ,Colony Count, Microbial ,Biopelícula ,Nursing ,medicine.disease_cause ,Tryptic soy broth ,Instrumentos Cirúrgicos ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Contaminación de Equipamientos ,medicine ,Escherichia coli ,Humans ,Food science ,General Nursing ,Chemistry ,Biofilm ,Seguridad del Paciente ,Contamination ,Segurança do Paciente ,Stainless Steel ,Surgical Instruments ,030104 developmental biology ,030220 oncology & carcinogenesis ,Biofilms ,Equipment Contamination ,Instrumentos Quirúrgicos ,Patient Safety ,Biofilmes - Abstract
Objectives: to evaluate the microbial load and adherence of Escherichia coli in different areas of the surgical instrument surface exposed to experimental contamination over time. Methods: experimental study in which fragments of crile forceps (serrated, rod and rack) were contaminated by immersion in Tryptic Soy Broth, containing 106 CFU/mL of E. coli, for 1, 2, 4, 6, 8, 12 and 24 hours. Microbial load and bacterial adherence were evaluated using microbiological culture and scanning electron microscopy, respectively. Results: there was an increase in the microbial load on the surgical instrument, proportional to the contamination interval, ranging from 102 after 1 hour to 105 CFU/cm2 in 24 hours. The presence of exopolysaccharide was detected after two hours of contamination. Conclusions: microbial load and adhesion of E. coli increased over time, reaching 105 CFU/cm2 after 24 hours of contamination, starting biofilm formation after two hours. RESUMEN Objetivos: evaluar la carga microbiana y adherencia de Escherichia coli en diferentes áreas de la superficie de instrumento quirúrgico expuesto a la contaminación experimental a lo largo del tiempo. Métodos: estudio experimental en que fragmentos de tenacillas quirúrgicas (sierra, asta y cremallera), contaminados por inmersión en Tryptic Soy Broth, conteniendo 106 UFC/mL de E. coli, por 1, 2, 4, 6, 8, 12 y 24 horas. La carga microbiana y la adherencia bacteriana evaluadas con uso de cultivo y microscopia electrónica de barredura, respectivamente Resultados: verificó aumento de la carga microbiana en el instrumento quirúrgico, proporcional al intervalo de contaminación, variando de 102 tras 1 hora a 105 UFC/cm2 en 24 horas. La presencia de polisacárido detectada tras 2 horas de contaminación. Conclusiones: carga microbiana y adherencia de E. coli aumentaron a lo largo del tiempo, atingiendo 105 UFC/cm2 tras 24 horas de contaminación, iniciándose formación de biopelícula tras 2 horas. RESUMO Objetivos: avaliar a carga microbiana e a aderência de Escherichia coli em diferentes áreas da superfície de instrumento cirúrgico exposto à contaminação experimental ao longo do tempo. Métodos: estudo experimental em que fragmentos de pinças crile (serrilha, haste e cremalheira) foram contaminados por imersão em Tryptic Soy Broth, contendo 106 UFC/mL de E. coli, por 1, 2, 4, 6, 8, 12 e 24 horas. A carga microbiana e a aderência bacteriana foram avaliadas com uso de cultura microbiológica e microscopia eletrônica de varredura, respectivamente. Resultados: verificou-se aumento da carga microbiana no instrumento cirúrgico, proporcional ao intervalo de contaminação, variando de 102 após 1 hora a 105 UFC/cm2 em 24 horas. A presença de exapolissacarídeo foi detectada após 2 horas de contaminação. Conclusões: carga microbiana e aderência de E. coli aumentaram ao longo do tempo, atingindo 105 UFC/cm2 após 24 horas de contaminação, iniciandose formação de biofilme após 2 horas.
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- 2020
34. Intra‐clade metabolomic profiling of MAR4 Streptomyces from the Macaronesia Atlantic region reveals a source of anti‐biofilm metabolites
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Rita G. Sobral, Susana P. Gaudêncio, Marisa Paulino, Camila C. Godinho, Vanessa T. Almeida, Alejandra Prieto-Davó, Florbela Pereira, Inês R. Grilo, Norberto Peporine Lopes, Leonardo Gobbo-Neto, and Anelize Bauermeister
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Staphylococcus aureus ,BIOFILMES ,medicine.disease_cause ,Microbiology ,Streptomyces ,03 medical and health sciences ,Metabolomics ,Antibiotic resistance ,Tandem Mass Spectrometry ,Phylogenetics ,medicine ,Marinobacter hydrocarbonoclasticus ,Phylogeny ,Ecology, Evolution, Behavior and Systematics ,030304 developmental biology ,0303 health sciences ,biology ,Terpenes ,030306 microbiology ,Biofilm ,biology.organism_classification ,Antimicrobial ,Anti-Bacterial Agents ,Biofilms ,Chromatography, Liquid - Abstract
The search for new and effective strategies to reduce bacterial biofilm formation is of utmost importance as bacterial resistance to antibiotics continues to emerge. The use of anti-biofilm agents that can disrupt recalcitrant bacterial communities can be an advantageous alternative to antimicrobials, as their use does not lead to the development of resistance mechanisms. Six MAR4 Streptomyces strains isolated from the Madeira Archipelago, at the unexplored Macaronesia Atlantic ecoregion, were used to study the chemical diversity of produced hybrid isoprenoids. These marine actinomycetes were investigated by analysing their crude extracts using LC-MS/MS and their metabolomic profiles were compared using multivariate statistical analysis (principal component analysis), showing a separation trend closely related to their phylogeny. Molecular networking unveiled the presence of a class of metabolites not previously described from MAR4 strains and new chemical derivatives belonging to the napyradiomycin and marinone classes. Furthermore, these MAR4 strains produce metabolites that inhibit biofilm formation of Staphylococcus aureus and Marinobacter hydrocarbonoclasticus. The anti-biofilm activity of napyradiomycin SF2415B3 (1) against S. aureus was confirmed.
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- 2019
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35. Formação e prevenção de biofilmes em cateteres urinários: uma análise biliométrica
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Evandro Watanabe, Rachel Maciel Monteiro, Denise de Andrade, Odinéa Maria Amorim Batista, Marinila Buzanelo Machado, Maria Eliete Batista Moura, and Pedro Castanhia Amadio Domingues
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Bibliometric analysis ,business.industry ,urinary catheters ,QH301-705.5 ,Urinary system ,Biofilm ,Agriculture ,Cateteres Urinários ,Bibliometrics ,Microbiology ,Biofilmes ,Urinary Catheters ,Bibliometria ,bibliometrics ,Biofilms ,Health Sciences ,Medicine ,biofilms ,Biology (General) ,General Agricultural and Biological Sciences ,business ,CATETERISMO URINÁRIO - Abstract
To map the scientific production about biofilms formation and prevention on urinary catheters. It is a bibliometric, exploratory, and descriptive research performed in Web of Science™, in three stages, and utilizing HistCite™ software. In this regard, descriptors “Biofilm*” AND “Urinary Catheter*” were utilized within the period between 1945 and 2016. A total of 329 articles about biofilm on urinary catheter were found from 1985 to 2016. These articles were written by 1,262 authors from 452 institutions located in 50 countries. The relation among the 15 selected articles, the most impacting ones, evidences the existence of experimental researches; most of them was in vitro. The control of biofilm formation on urinary catheters remains as a major challenge in the health area, because new ways are necessary to improve the prevention and minimization of this phenomenon. Mapear a produção científica acerca da formação e prevenção de biofilmes em cateteres urinários. Trata-se de uma pesquisa bibliométrica, exploratória e descritiva, realizada no Web of Science™, em três estágios, e utilizando o software HistCite™. Nesse sentido, foram utilizados os descritores “Biofilme*” E “Cateter Urinário*” no período de 1945 a 2016. Foram encontrados 329 artigos sobre biofilme em cateter urinário no período de 1985 a 2016. Estes artigos foram escritos por 1.262 autores de 452 instituições localizadas em 50 países. A relação entre os 15 artigos selecionados, os mais impactantes, evidencia a existência de pesquisas experimentais; a maioria delas foi in vitro. O controle da formação de biofilme nos cateteres urinários permanece como um grande desafio na área da saúde, pois são necessárias novas formas de melhorar a prevenção e a minimização desse fenômeno.
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- 2020
36. Diversidade Microbiana em Região Peri-Implantar de Pacientes com Histórico de Doença Periodontal e Parâmetros Clínicos
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Tassiana Carvalho Mendonça Galvão, Juliana Barbosa de Faria, Luis Henrique Borges, Camila Beatriz Silva, Eleonora de Paula Amaral, Bárbara Bellocchio Bertoldo, Taíssa Cássia de Souza Furtado, Denise Bertulucci Rocha Rodrigues, Vinicius Rangel Geraldo-Martins, Sanivia Aparecida de Lima Pereira, and Ruchele Dias Nogueira
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Implantes dentales ,Mucositis periimplantaria ,Implantação dentária ,Mucosite peri-implantar ,Peri-implant mucositis ,Biofilm ,Dental implants ,General Earth and Planetary Sciences ,Peri-implantitis ,Peri-implantite ,Periimplantitis ,Biofilmes ,General Environmental Science - Abstract
Although implant rehabilitations are successful, a small portion of patients may present peri-implant mucositis and peri-implantitis due to the bacteria biofilm formation. The purpose of the present study was to evaluate the presence of Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Fusobacterium nucleatum (Fn) and Scardovia wiggsiae (Sw) in Peri-implant gingival Fluid (PGF) of patients who received implants 12 months ago and associated with periodontitis (PD) history and clinical data. Samples were collected from 44 volunteers and analyzed by PCR with specific primers. The results showed that Pg were detected in 34%, Fn and Pi, 81.8%, and Sw 75% of the volunteers. Pg was frequently detected in patients who had a history of PD (p0.05, q0,5, q0,05, q
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- 2022
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37. BIOFILME: AMEAÇA INVÍSIVEL EM AMBIENTES CIRÚRGICOS.
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Rodrigues da SILVA, Hygor, Roberto Reginato REGINI, Jefferson, and NEGRI, Melyssa
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INFECTION , *COMMUNICABLE diseases , *PUBLIC health , *BIOFILMS , *ANTI-infective agents - Abstract
Acquired infections related to health care (IRHC) represent serious public health problems and the main risk factors for the use of medical devices or surgical implants that are a source of microbial infection. It is known that most populations' microorganisms, regardless of the context in which they are, tend to preferentially form aggregates of various species or a single species, forming a microbial community called biofilm. The microbial biofilms are groups of cells adhered to a surface and to each other, embedded in a matrix of extracellular polymeric substances, in which the same are produced by the microorganisms in order to increase their chance of survival in a given environment, acting as a barrier filter, generating a reduced penetration of antimicrobial agents. Thus in the area of health, the formation of biofilms on medical devices directly connected to the patient, even in the presence of the same machines or in indirect contact with the individual, are situations that bring concerns to professionals. Therefore, to Acquired infections related to health care (IRHC) represent serious public health problems and the main risk factors for the use of medical devices or surgical implants that are a source of microbial infection. It is known that most populations' microorganisms, regardless of the context in which they are, tend to preferentially form aggregates of various species or a single species, forming a microbial community called biofilm. The microbial biofilms are groups of cells adhered to a surface and to each other, embedded in a matrix of extracellular polymeric substances, in which the same are produced by the microorganisms in order to increase their chance of survival in a given environment, acting as a barrier filter, generating a reduced penetration of antimicrobial agents. Thus in the area of health, the formation of biofilms on medical devices directly connected to the patient, even in the presence of the same machines or in indirect contact with the individual, are situations that bring concerns to professionals. Therefore, to better understand this process IRHC by microbial communities is important to understand how biofilm formation occurs in a hospital setting, its complications and ways to prevent this process, so this work is to clarify the scientific community's health complexity that is a biofilm within a hospital setting. [ABSTRACT FROM AUTHOR]
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- 2013
38. Effectiveness of manual and electric brushes in the removal of biofilm from full dentures.
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Machado de ANDRADE, Ingrid, Costa CRUZ, Patrícia, Fuzaro ZAMBONE, Bárbara, SILVA-LOVATO, Cláudia Helena, Freitas de SOUZA, Raphael, Monteiro de SOUZA-GUGELMIN, Maria Cristina, and de Freitas Oliveira PARANHOS, Helena
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TOOTHBRUSHES ,ORAL hygiene products ,ORAL hygiene ,DENTURE equipment ,BIOFILMS - Abstract
Copyright of RGO: Revista Gaúcha de Odontologia is the property of RGO: Revista Gaucha de Odontologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2013
39. Antibacterial properties of silver nanoparticles as a root canal irrigant against Enterococcus faecalis biofilm and infected dentinal tubules
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C. T. Rodrigues, Marco Antonio Hungaro Duarte, Norberti Bernardineli, L. R. S. M. de Vasconcelos, Milton Carlos Kuga, Raquel Zanin Midena, Thais Cristina Pereira, and F. B. de Andrade
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Silver ,BIOFILMES ,Root canal ,Metal Nanoparticles ,02 engineering and technology ,Silver nanoparticle ,Enterococcus faecalis ,Microbiology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,stomatognathic system ,medicine ,Animals ,General Dentistry ,Gram-Positive Bacterial Infections ,Root Canal Irrigants ,biology ,Chlorhexidine ,Biofilm ,030206 dentistry ,biochemical phenomena, metabolism, and nutrition ,021001 nanoscience & nanotechnology ,Antimicrobial ,biology.organism_classification ,Anti-Bacterial Agents ,medicine.anatomical_structure ,Dentinal Tubule ,chemistry ,Biofilms ,Sodium hypochlorite ,Cattle ,0210 nano-technology ,medicine.drug - Abstract
AIM To evaluate the antimicrobial action of an irrigant containing silver nanoparticles in an aqueous vehicle (AgNp), sodium hypochlorite and chlorhexidine against Enterococcus faecalis biofilm and infected dentinal tubules. METHODOLOGY Bovine dentine blocks were used for E. faecalis biofilm development for 21 days and irrigated with 94 ppm AgNp solution, 2.5% NaOCl and 2% chlorhexidine for 5, 15 and 30 min. For infection of dentinal tubules with E. faecalis, dentine specimens from bovine incisors were submitted to a contamination protocol over 5 days, with eight centrifugation cycles on every alternate day, and irrigated with the same solutions and time intervals used for the biofilm. The specimens were stained with the Live/Dead technique and evaluated using a confocal laser scanning microscope (CLSM). The bioImage_L software was used for measurement of the total biovolume of biofilm in μm3 and percentage of viable bacteria (green cells) in biofilm and in dentinal tubules found after the irrigation. Statistical analyses were performed using Kruskal-Wallis and Dunn's tests for quantification of viable cells in biofilm, the Friedman test for comparisons of viable bacteria in dentinal tubules in different areas of the root canal and the Mann-Whitney U-test to compare the action of the irrigants between the two methods (P
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- 2018
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40. Can sono-photodynamic therapy enhance the antibacterial effect of curcumin against Streptococcus mutans biofilm?
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Vanderlei Salvador Bagnato, Adilson César de Abreu Bernardi, Alessandra Nara de Souza Rastelli, João Felipe Besegato, Priscila Borges Gobbo de Melo, Universidade Estadual Paulista (UNESP), University of Araraquara - Uniara, and Universidade de São Paulo (USP)
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Physics and Astronomy (miscellaneous) ,biology ,BIOFILMES ,Chemistry ,medicine.medical_treatment ,Biofilm ,Photodynamic therapy ,Antibacterial effect ,biology.organism_classification ,Streptococcus mutans ,biofilm ,Microbiology ,chemistry.chemical_compound ,photodynamic therapy ,Curcumin ,medicine ,curcumin ,sono-photodynamic therapy ,Instrumentation - Abstract
Made available in DSpace on 2022-04-29T08:33:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-10-01 Sono-photodynamic therapy (SPDT) is a combined therapy which employs the use of a light source and ultrasound activation for antimicrobial purposes. This study evaluated the antibacterial effect of curcumin-mediated SPDT against Streptococcus mutans biofilm. Absorption spectra of curcumin was determined under UV-visible region (200-800 nm). The generation of reactive oxygen species was evaluated using a fluorescence probe (singlet oxygen sensor green). Minimum inhibitory and minimum bacterial concentrations were determined. S. mutans biofilm was cultured and treated according to the groups as follows: L - PS - U- (negative control), chlorhexidine (positive control), L + PS + U- (aPDT groups), L - PS + U+ (SDT groups), L + PS + U+ (SPDT groups). Before irradiation, the biofilms were incubated for 5 min and irradiated by blue light emitting-diode at 15 J cm-2. For the dark toxicity, the groups were exposed to the same conditions, but no light was used. After treatments, counting of colonies forming units was performed. Confocal microscopy images were obtained. Data were statistically analyzed by ANOVA and Tukey's test (p 0.05). Curcumin under 80 µM showed higher absorption than 40 µM. For the generation of reactive species, antimicrobial photodynamic therapy and SPDT exhibited similar behavior. Minimum inhibitory concentration and minimum bactericidal concentration were 40 and 80 µM, respectively. Curcumin under 40 and 80 µM showed no dark toxicity. SPDT showed better results than isolated therapies, since significant reduction (3.8 log10; p 0.001) over the cell viability was observed. This result was confirmed by confocal images. Curcumin showed promising results as a photosensitizer for SPDT. Moreover, curcumin-mediated SPDT exhibited enhanced antibacterial effects and may be an alternative therapy to control the oral biofilm. Department of Restorative Dentistry School of Dentistry São Paulo State University - UNESP Araraquara Department of Biology and Health Sciences University of Araraquara - Uniara Physics Institute of São Carlos-IFSC University of São Paulo - Usp Department of Restorative Dentistry School of Dentistry São Paulo State University - UNESP Araraquara
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- 2021
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41. Effects of curcumin-mediated antimicrobial photodynamic therapy associated to different chelators against Enterococcus faecalis biofilms
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Patrícia de Almeida Rodrigues, Victor Feliz Pedrinha, Daniela Alejandra Cusicanqui Méndez, Evelyn Giuliana Velásquez Espedilla, Thiago Cruvinel, Flaviana Bombarda de Andrade, and Maricel Rosario Cardenas Cuéllar
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Curcumin ,BIOFILMES ,Biophysics ,Ethylenediaminetetraacetic acid ,Dermatology ,Enterococcus faecalis ,Microbiology ,chemistry.chemical_compound ,Anti-Infective Agents ,Animals ,Pharmacology (medical) ,Chelation ,Chelating Agents ,Colony-forming unit ,Photosensitizing Agents ,biology ,Chemistry ,Biofilm ,Antimicrobial ,biology.organism_classification ,Photochemotherapy ,Oncology ,Biofilms ,Brain heart infusion ,Cattle - Abstract
Background The aim of this study was to evaluate curcumin-mediated antimicrobial photodynamic therapy (aPDT) action combined or not with ethylenediaminetetraacetic acid (EDTA) and hydroxyethylidene bisphosphonate (HEBP) on Enterococcus faecalis biofilms. Methods Enterococcus faecalis biofilms were grown on dentin bovine discs in brain heart infusion (BHI) medium with 1% glucose, in aerobic conditions at 37°C for 7 days. Then, they were randomly distributed to one of experimental conditions, as follows: control, 75 J.cm−2 LED, 600 μmol.L−1 curcumin, 17% EDTA, 18% HEBP, 600 μmol.L−1 curcumin plus 75 J.cm−2 LED, 600 μmol.L−1 curcumin plus 17% EDTA, 600 μmol.L−1 curcumin plus 18% HEBP, 600 μmol.L−1 curcumin plus 17% EDTA and 75 J.cm−2 LED or 600 μmol.L−1 curcumin plus 18% HEBP and 75 J.cm−2 LED. The viability of microorganisms and the vitality of biofilms were determined by colony forming unit counts and confocal scanning laser microscopy (CSLM), respectively. Statistical analysis was conducted by Kruskal Wallis and Dunn's post-hoc tests (α = 0.05). Results The results showed that all combinations of aPDT with chelators significantly reduced the viability of microbial cells and the vitality of biofilms in comparison to control, even when considering deeper layers of biofilms. Conclusion The combination of curcumin with EDTA and HEBP similarly improved the effect of aPDT on E. faecalis biofilms.
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- 2021
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42. Genetic diversity and research of Escherichia coli, extended spectrum β-lactamase (ESBL) producing, isolated from milk of cows with clinical mastitis
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Orsi, Henrique, Universidade Estadual Paulista (Unesp), Rall, Vera Lúcia Mores [UNESP], and Hernandes, Rodrigo Tavanelli [UNESP]
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KPC ,Phylogenetic group ,Grupo filogenético ,Biofilm ,PFGE ,Biofilmes - Abstract
Submitted by Henrique Orsi (henrique.orsi@unesp.br) on 2020-04-20T19:05:27Z No. of bitstreams: 1 Dissertação Henrique - Publicação no repositório.pdf: 2075102 bytes, checksum: b32bf50b1002f1113ad4f30dc07e1854 (MD5) Submitted by Henrique Orsi (henrique.orsi@unesp.br) on 2020-04-20T19:05:27Z No. of bitstreams: 1 Dissertação Henrique - Publicação no repositório.pdf: 2075102 bytes, checksum: b32bf50b1002f1113ad4f30dc07e1854 (MD5) Submitted by Henrique Orsi (henrique.orsi@unesp.br) on 2020-04-20T19:05:27Z No. of bitstreams: 1 Dissertação Henrique - Publicação no repositório.pdf: 2075102 bytes, checksum: b32bf50b1002f1113ad4f30dc07e1854 (MD5) Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2020-04-23T18:08:43Z (GMT) No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2020-04-23T18:08:43Z (GMT) No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Submitted by Henrique Orsi (henrique.orsi@unesp.br) on 2020-04-20T19:05:27Z No. of bitstreams: 1 Dissertação Henrique - Publicação no repositório.pdf: 2075102 bytes, checksum: b32bf50b1002f1113ad4f30dc07e1854 (MD5) Made available in DSpace on 2020-04-23T18:08:43Z (GMT). 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No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Previous issue date: 2020-02-21 Made available in DSpace on 2020-04-23T18:08:43Z (GMT). No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Previous issue date: 2020-02-21 Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2020-04-23T18:08:43Z (GMT) No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Made available in DSpace on 2020-04-23T18:08:43Z (GMT). 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No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Previous issue date: 2020-02-21 Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2020-04-23T18:08:43Z (GMT) No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Made available in DSpace on 2020-04-23T18:08:43Z (GMT). No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Previous issue date: 2020-02-21 Made available in DSpace on 2020-04-23T18:08:43Z (GMT). No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Previous issue date: 2020-02-21 Submitted by Henrique Orsi (henrique.orsi@unesp.br) on 2020-04-20T19:05:27Z No. of bitstreams: 1 Dissertação Henrique - Publicação no repositório.pdf: 2075102 bytes, checksum: b32bf50b1002f1113ad4f30dc07e1854 (MD5) Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2020-04-23T18:08:43Z (GMT) No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Made available in DSpace on 2020-04-23T18:08:43Z (GMT). No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Previous issue date: 2020-02-21 Made available in DSpace on 2020-04-23T18:08:43Z (GMT). No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Previous issue date: 2020-02-21 Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2020-04-23T18:08:43Z (GMT) No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Made available in DSpace on 2020-04-23T18:08:43Z (GMT). No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Previous issue date: 2020-02-21 Made available in DSpace on 2020-04-23T18:08:43Z (GMT). No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Previous issue date: 2020-02-21 Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2020-04-23T18:08:43Z (GMT) No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2020-04-23T18:08:43Z (GMT) No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Made available in DSpace on 2020-04-23T18:08:43Z (GMT). No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Previous issue date: 2020-02-21 Made available in DSpace on 2020-04-23T18:08:43Z (GMT). No. of bitstreams: 1 orsi_h_me_bot_par.pdf: 774710 bytes, checksum: 6284042e47ae892dfc37b4fce119612b (MD5) Previous issue date: 2020-02-21 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) A mastite bovina é uma inflamação da glândula mamária, geralmente ocasionada por micro-organismos, que causa grandes prejuízos às fazendas leiteiras, devido ao uso de medicamentos, pagamento aos médicos veterinários, descarte de leite e até do animal e a Escherichia coli é o principal agente etiológico causador da forma clínica dessa doença. Neste trabalho, foram pesquisados genes para a classificação de E. coli diarreiogênica (DEC) ou de E. coli patogênica extra-intestinal (ExPEC), dentro dos grupos filogenéticos, além de genes que codificam fatores de virulência e resistência aos antimicrobianos. Também foram realizados testes de quantificação de produção de biofilme e produção de beta-lactamase de espectro estendido (ESBL). Entre os 161 isolados, dois (1,2%) foram classificados como DEC. Considerando-se os genes pesquisados, os mais frequentes foram fimH (160 = 99,3%), traT (126 = 78,3%), ecpA (108 = 67%) e ompT (60 = 37,3%). Em relação aos grupos filogenéticos, a maioria foi classificada nos grupos B1 (52,8%) e A (36,6%). Quanto à produção de biofilme, 68 (42,2%) foram classificadas como não produtoras, 80 (49,7%) como fracas, 11 (6,8%) como moderadas e apenas duas (1,2%) foram fortes produtoras. Apenas dois (1,2%) isolados apresentaram positividade no teste fenotípico de ESBL, com a presença do gene blaCTX-M-15. Considerando-se outros genes de resistência, blaTEM foi encontrado em sete (4,3%) isolados e blaSHV em um (0,6%). Os dois (1,2%) isolados escN+ apresentaram padrão de aderência “localizado-like” em células HeLa e seu potencial de induzir lesão attaching/effacing foi confirmado através de teste de coloração fluorescente da actina (FAS). Em relação ao PFGE, foram encontrados 10 clones, envolvendo tanto animais diferentes quanto o mesmo animal em diferentes períodos de coleta, indicando manejo inadequado. Não foi possível definir um perfil genético característico para as E. coli patogênicas da glândula mamária (MPECs) e, como apenas dois isolados apresentaram genes e padrão de adesão característicos de DEC, parece haver pouco potencial zoonótico para os isolados causadores de mastite bovina clínica. Bovine mastitis is an inflammation of the mammary gland, usually caused by microorganisms, which causes great damage to dairy farms, due to the use of medicines, payment to veterinarians, disposal of milk and even the animal and Escherichia coli is the main etiologic agent that causes the clinical form of this disease. In this study, genes were searched for the classification of diarrhogenic E. coli (DEC) or extra-intestinal pathogenic E. coli (ExPEC), within the phylogenetic groups, in addition to genes that encode virulence factors and resistance to antimicrobials. Quantification tests of biofilm production and production of extended spectrum beta-lactamase (ESBL) were also performed. Among the 161 isolates, two (1.2%) were classified as DEC. Considering the researched genes, the most frequent were fimH (160 = 99.3%), traT (126 = 78.3%), ecpA (108 = 67%) and ompT (60 = 37.3%). Regarding phylogenetic groups, most were classified in groups B1 (52.8%) and A (36.6%). As for the production of biofilm, 68 (42.2%) were classified as non-producing, 80 (49.7%) as weak, 11 (6.8%) as moderate and only two (1.2%) were strong producers. Only two (1.2%) isolates were positive in the ESBL phenotypic test, with the presence of the blaCTX-M-15 gene. Considering other resistance genes, blaTEM was found in seven (4.3%) isolates and blaSHV in one (0.6%). The two (1.2%) escN+ isolates showed a “localized-like” adhesion pattern in HeLa cells and their potential to induce attaching/effacing lesion was confirmed through fluorescent actin staining (FAS) test. Regarding PFGE, 10 clusters were found, involving both different animals and the same animal in several periods of collection, indicating inadequate handling. It was not possible to define a characteristic genetic profile for mammary pathogenic E. coli (MPECs) and, as only two isolates had genes and adhesion pattern characteristic of DEC, there is little zoonotic potential for isolates that cause clinical bovine mastitis. CAPES: 001
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- 2020
43. Influence of organic loading rate on ciprofloxacin and sulfamethoxazole biodegradation in anaerobic fixed bed biofilm reactors
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Rodrigo B. Carneiro, Caio M. Mukaeda, Álvaro J. Santos-Neto, Marcelo Zaiat, and Carolina A. Sabatini
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Environmental Engineering ,Hydraulic retention time ,Sulfamethoxazole ,Methanogenesis ,BIOFILMES ,0208 environmental biotechnology ,02 engineering and technology ,010501 environmental sciences ,Management, Monitoring, Policy and Law ,01 natural sciences ,Waste Disposal, Fluid ,Bacteria, Anaerobic ,Bioreactors ,Biogas ,Ciprofloxacin ,Bioreactor ,Anaerobiosis ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Packed bed ,Sewage ,Chemistry ,Biofilm ,General Medicine ,Biodegradation ,Pulp and paper industry ,020801 environmental engineering ,Biodegradation, Environmental ,Biofilms ,Sewage treatment - Abstract
Antibiotic compounds, notably sulfamethoxazole (SMX) and ciprofloxacin (CIP), are ubiquitous emerging contaminants (ECs), which are often found in domestic sewage. They are associated with the development of antimicrobial resistance. Operational parameters, e.g. organic loading rate (OLR), hydraulic retention time (HRT) and sludge retention time, may influence EC biodegradation in wastewater treatment plants. This study assessed the impact of the OLR variation on the biodegradation of CIP and SMX, applying two configurations of anaerobic fixed bed reactors: anaerobic packed bed biofilm reactor (APBBR) and anaerobic structured bed biofilm reactor (ASBBR). A significant reduction in the biodegradation of SMX (APBBR: 93-69%; ASBBR: 94-81%) and CIP (APBBR: 85-66%; ASBBR: 85-64%) was observed increasing OLR from 0.6 to 2.0 kgCOD m-3 d-1. The decrease in the HRT from 12 to 4 h resulted in higher liquid-phase mass transfer coefficient (APBBR: ks from 0.01 to 0.05 cm h-1; ASBBR: ks from 0.07 to 0.24 cm h-1), but this was not enough to overcome the decrease in the antibiotic-biomass contact time on biofilm, thus reducing the bioreactors' performance. The ASBBR favored biomethane production (from 7 to 17 mLCH4 g-1VSS L-1 d-1) and biodegradation kinetics (kbio from 1.7 to 4.2 and for SMX and from 2.1 to 4.8 L g-1VSS d-1 for CIP) due to the higher relative abundance of the archaea community in the biofilm and the lower liquid-phase mass transfer resistance in the structured bed. CIP and SMX cometabolic biodegradation was associated to the hydrogenotrophic methanogenesis (mainly Methanobacterium genus) in co-culture with fermentative bacteria (notably the genera Clostridium, Bacillus, Lactivibrio, Syntrophobacter and Syntrophorhabdus). The anaerobic fixed bed biofilm reactors proved to be highly efficient in biodegrading the antibiotics, preventing them from spreading to the environment.
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- 2020
44. Atividade antimicrobiana de superfícies de cobre frente à formação de biofilmes por Salmonella enteritidis e sua potencial aplicação na indústria avícola
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Pontin, Karine Patrin, Nascimento, Vladimir Pinheiro do, and Borges, Karen Apellanis
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Antimicrobial properties ,Cobre ,Salmonella enteritidis ,Industria avícola ,Salmonella ,Biofilm ,Atividade antimicrobiana ,Biofilmes ,Copper - Abstract
Salmonella é considerada um dos patógenos de maior relevância para o setor avícola, uma vez que a carne de frango representa a principal fonte de infecção desta bactéria para o homem. O sorovar S. Enteritidis é identificado como o mais frequentemente envolvido nas salmoneloses alimentares. Na indústria, o controle de biofilmes é rotineiramente realizado através da higienização com a utilização de desinfetantes, os quais apresentam toxicidade conhecida e eficácia variável, devido à evolução da resistência antimicrobiana. O cobre vem sendo aplicado como superfície de contato com poder antimicrobiano em diversos países e pode ser utilizado como um complemento das práticas padrão de limpeza e desinfecção das superfícies industriais, conferindo redução da formação de biofilmes, diminuição da carga bacteriana persistente e aumentando a segurança dos alimentos. Neste contexto, o presente estudo teve como objetivo avaliar as propriedades antimicrobianas de superfícies de cobre e suas ligas na prevenção da formação do biofilme por S. Enteritidis e avaliar o potencial de corrosão das superfícies, quando em contato com desinfetante. Para avaliação da atividade antimicrobiana, foram utilizados cupons com área de 1 cm2, compostos de cobre 99,9% (C11000), latão (C26000), cobre revestido com estanho e, como controle, aço inoxidável (AISI 316). O método utilizado foi o de diluição, com teste de suspensão de células planctônicas e contagem bacteriana realizada através do método de Drop plate, com posterior incubação em temperaturas que simulam ambientes de processamento avícola (4ºC, 12ºC e 25ºC). Para a avaliação do potencial de corrosão, foram realizados ensaios de polarização potenciostática com as mesmas superfícies. Diferenças estatísticas significativas (p
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- 2020
45. Myristyltrimethylammonium Bromide (MYTAB) as a cationic surface agent to inhibit Streptococcus mutans grown over dental resins: an in vitro study
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Castelo Branco Leitune, Isadora Martini Garcia, Júlia Silveira Nunes, Mary Anne S. Melo, Fabrício Mezzomo Collares, Fernanda Visioli, and Mena Silva Pa
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Materials science ,Dental materials ,lcsh:Biotechnology ,Biomedical Engineering ,biocompatible materials ,02 engineering and technology ,Biomaterials ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,anti-bacterial agents ,stomatognathic system ,Bromide ,Anti-bacterial agents ,lcsh:TP248.13-248.65 ,Ultimate tensile strength ,dental materials ,quaternary ammonium compounds ,Biocompatible materials ,lcsh:R5-920 ,biology ,dentistry ,Biofilm ,Cationic polymerization ,Cárie dentária ,030206 dentistry ,Compostos de amônio quaternário ,021001 nanoscience & nanotechnology ,biology.organism_classification ,Streptococcus mutans ,Monomer ,chemistry ,Antibacterianos ,Materiais dentários ,Biofilms ,Materiais biocompatíveis ,dental caries ,Dental caries ,biofilms ,0210 nano-technology ,Antibacterial activity ,lcsh:Medicine (General) ,Photoinitiator ,Biofilmes ,Quaternary ammonium compounds ,Nuclear chemistry - Abstract
This in vitro study evaluated the effect of myristyltrimethylammonium bromide (MYTAB) on the physical, chemical, and biological properties of an experimental dental resin. The resin was formulated with dental dimetacrylate monomers and a photoinitiator/co-initiator system. MYTAB was added at 0.5 (G0.5%), 1 (G1%), and 2 (G2%) wt %, and one group remained without MYTAB and was used as the control (GCtrl). The resins were analyzed for the polymerization kinetics, degree of conversion, ultimate tensile strength (UTS), antibacterial activity against Streptococcus mutans, and cytotoxicity against human keratinocytes. Changes in the polymerization kinetics profiling were observed, and the degree of conversion ranged from 57.36% (±, 2.50%) for G2% to 61.88% (±, 1.91%) for G0.5%, without a statistically significant difference among groups (p >, 0.05). The UTS values ranged from 32.85 (±, 6.08) MPa for G0.5% to 35.12 (±, 5.74) MPa for GCtrl (p >, 0.05). MYTAB groups showed antibacterial activity against biofilm formation from 0.5 wt % (p <, 0.05) and against planktonic bacteria from 1 wt % (p <, 0.05). The higher the MYTAB concentration, the higher the cytotoxic effect, without differences between GCtrl e G0.5% (p >, 0.05). In conclusion, the addition of 0.5 wt % of MYTAB did not alter the physical and chemical properties of the dental resin and provided antibacterial activity without cytotoxic effect.
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- 2020
46. Conjugate of chitosan nanoparticles with chloroaluminium phthalocyanine: synthesis, characterization and photoinactivation of Streptococcus mutans biofilm
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Antonio Claudio Tedesco, Luandra Aparecida Unten Takahashi, Leonardo Lobo Ribeiro Cavalcante, Fabiana Almeida Curylofo-Zotti, Silmara Aparecida Milori Corona, and Aline Evangelista Souza-Gabriel
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Indoles ,BIOFILMES ,030303 biophysics ,Biophysics ,Nanoparticle ,Dermatology ,Streptococcus mutans ,030207 dermatology & venereal diseases ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Zeta potential ,Organometallic Compounds ,Animals ,Pharmacology (medical) ,Photosensitizer ,0303 health sciences ,Chitosan ,Photosensitizing Agents ,biology ,Chemistry ,Biofilm ,biology.organism_classification ,Antimicrobial ,Oncology ,Photochemotherapy ,Biofilms ,Phthalocyanine ,Nanoparticles ,Cattle ,Phototoxicity ,Nuclear chemistry - Abstract
Background Antimicrobial photodynamic therapy (aPDT) using chloroaluminium phthalocyanine (ClAlPc) has high oxidative power allowing for the control of biofilms, especially when the photosensitizer is administered in an appropriate release vehicle. This study aimed to develop/characterize the ClAlPc encapsulated in chitosan nanoparticles (CSNPs), and evaluate its antimicrobial properties against S. mutans biofilms. Methods CSNPs were prepared by ion gelation, and characterization studies included particle size, polydispersion index (IPd), zeta potential, accelerated stability, absorption spectrum and ClAlPc quantification. The S. mutans biofilms were formed in bovine dentin blocks at 37 °C for 48 h under microaerophilic conditions. 8 μM ClAlPc was combined with a diode laser (InGaAlP) at 660 nm and 100 J/cm2. The aPDT toxicity was verified by dark phototoxicity. The antimicrobial activity was verified by CFU/mL and biofilm was analyzed by scanning electron microscopy (SEM). The number of viable bacteria was analyzed by ANOVA and Tukey HSD tests (α = 0.05). Results The characterization revealed that the ClAlPc nanoparticles were found in nanometer-scale with adequate photophysical and photochemical properties. The aPDT mediated by ClAlPc + CSNPs nanoconjugate showed a significant reduction in the viability of S. mutans (1log10 CFU/mL) compared to the negative control (PBS, p 0.05). SEM revealed change in biofilm morphology following the treatment of bacteria with aPDT ClAlPc + CSNPs. Cells were arranged as single or in shorted chains. Irregular shapes of S. mutans were found. Conclusion ClAlPc nanoparticles are considered stable and aPDT mediated by ClAlPc + CSNPs nanoconjugate was effective against S. mutans biofilm.
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- 2020
47. Rational selection of antifungal drugs to propose a new formulation strategy to control Candida biofilm formation on venous catheters
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Paula Reginatto, Irene Clemes Külkamp Guerreiro, Saulo Fernandes de Andrade, Alexandre Meneghello Fuentefria, Simone Jacobus Berlitz, and Vanessa Zafanelli Bergamo
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Film-forming system ,medicine.medical_specialty ,Polyurethane ,Antifungal Agents ,Clinical Microbiology - Research Paper ,Microbiology ,Composição de medicamentos ,Association ,03 medical and health sciences ,Medical microbiology ,Amphotericin B ,Media Technology ,medicine ,Central Venous Catheters ,030304 developmental biology ,Candida ,Anidulafungina ,Voriconazole ,Catheter ,0303 health sciences ,030306 microbiology ,business.industry ,Biofilm ,Candidiasis ,Drug Synergism ,bacterial infections and mycoses ,Corpus albicans ,Drug Combinations ,análise [Compostos químicos] ,Biofilms ,Catheter-Related Infections ,Anidulafungin ,Ketoconazole ,Sinergismo farmacológico ,business ,Antifúngicos ,Fluconazole ,Biofilmes ,medicine.drug - Abstract
INTRODUCTION: Infections associated with medical devices are often related to colonization by Candida spp. biofilm; in this way, numerous strategies have been developed and studied, mainly in order to prevent this type of fungal growth. AIM: Considering the above, the main objective of the present study is to make a rational choice of the best antifungal therapy for the in vitro treatment of the biofilm on venous catheters, proposing an innovative formulation of a film-forming system to coat the surface in order to prevent the formation of biofilms. METHODOLOGY: Anidulafungin, fluconazole, voriconazole, ketoconazole, amphotericin B, and the association of anidulafungin and amphotericin B were tested against biofilms of C. albicans, C. tropicalis, and C. parapsilosis strains in microtiter plates and in a polyurethane catheter. Besides, anidulafungin, amphotericin B, and the combination of both were incorporated in a film-forming system and were evaluated against biofilm. RESULTS: The superior activity of anidulafungin was demonstrated in relation to the other antifungal agents. Although amphotericin B showed good activity, high concentrations were required. The combination showed a synergistic action, in solution and in the formulation, showing excellent results, with activity above 90%. CONCLUSION: Due to the superiority of anidulafungin and the synergistic activity of the combination, these alternatives were the most promising options for use in a formulation proposal as a new strategy to combat the Candida spp. biofilm. These formulations demonstrated high in vitro performance in the prevention of biofilms, indicating that they are candidates with great potential for in vivo tests. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s42770-020-00242-z) contains supplementary material, which is available to authorized users.
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- 2020
48. Valorization of chicken feet by-product of the poultry industry: high qualities of gelatin and biofilm from extraction of collagen
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Linda L Ho, Fernando Tobal Berssaneti, Roberta B Gardim, Ada P. B. Quispe, Felix Martin Carbajal Gamarra, Giovanna B Borini, Segundo A. V. Llanos, Jorge Heredia, Stella Zamuner, Poliana Fernandes de Almeida, Thiago M. B Farias, and José Carlos Curvelo Santana
- Subjects
collagen ,food.ingredient ,Absorption of water ,Polymers and Plastics ,BIOFILMES ,sensorial quality ,Gelatin ,Article ,health care product ,lcsh:QD241-441 ,gelatin ,Acetic acid ,chemistry.chemical_compound ,0404 agricultural biotechnology ,food ,lcsh:Organic chemistry ,By-product ,chemical quality ,Food science ,chicken feet ,business.industry ,Extraction (chemistry) ,0402 animal and dairy science ,Biofilm ,04 agricultural and veterinary sciences ,General Chemistry ,Poultry farming ,040401 food science ,040201 dairy & animal science ,chemistry ,Yield (chemistry) ,biofilms ,business - Abstract
In this research, products with high quality were obtained from natural sources. The sensorial qualities, chemical characterization, and physical properties of gelatin extracted from chicken feet were compared with commercial gelatins. The extraction process was performed using acetic acid on a concentration ranging from 0.318% to 3.682%, processing time between 1.0 h and 8.4 h and extraction temperature between 43.3 °, C and 76.8 °, C. After the end of each assay, the yield was measured. Results showed that, under the best conditions, the collagen extraction yield was above 8%, and comprised 78.525 g/100 g of protein. Collagen analyzed by ICP-MS was composed of 99.44% of macro-minerals that are of great importance to human health. ATR-FTIR analysis showed that approximately 70.90% of the total protein from chicken feet is collagen, whereas, in commercial gelatin, only 30.31% is collagen. When comparing chicken gelatin with commercial gelatin, most sensory attributes were similar and chicken gelatin gained acceptance by more than 80% of the consumers. Additionally, the collagen films obtained from chicken feet and swine showed water absorption, odors, and texture characteristics similar to commercial material, such as latex and celofane. Consequently, due to its similarity to human skin, it is possible to apply it as a biocurative.
- Published
- 2020
49. Biofilm formation by Aquaspirillum spp. and saprophytic Leptospira spp. isolated from environmental source of Argentine
- Author
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Silvina Quintana, Sylvia Grune Loffler, Pablo Aguirre, Bibiana Brihuega, Yanina Paola Videla, and Exequiel Scialfa
- Subjects
Argentina ,Biology ,Saprofitismo ,Microbiology ,Isolation ,Aquaspirillum ,Leptospira ,medicine ,Aquaspirillum spp ,Saprophytism ,Molecular Biology ,Aislamiento ,Biofilm ,cell aggregation ,Isolation (microbiology) ,medicine.disease ,biology.organism_classification ,Leptospirosis ,Cell aggregation ,Fresh water ,Aquatic environment ,Biotecnología Agrícola y Biotecnología Alimentaria ,Biofilmes ,Food Science ,Biotechnology - Abstract
Leptospirosis is a zoonotic disease of global distribution, caused by bacteria of the genus Leptospira. These spirochetes are living organisms free of mud and water; pathogenic leptospires can survive several days in fresh water when pH and temperature are adequate. During 2016, water samples were collected from Callvú Leovú stream (Azul, Buenos Aires); samples were inoculated in liquid EMJH medium and incubated at 28° C for 90 days. Six isolates of saprophytic leptospires and six of spirils (Aquaspirillum spp.) were obtained. The isolates were inoculated in EMJH (liquid and semi-solid) medium and sterile stream water at 4-10° C and 28-30° C; development was observed periodically using dark field microscopy. Both bacteria (alone or together) grew exponentially in first three weeks in all media incubated at 28-30° C; the semi-solid medium was the most efficient at 28-30° C of incubation, and the bacteria remained viable after 16 weeks. At 4-8° C both bacteria remained undetectable but viable in media incubated at 4-8° C for three weeks until the temperature was optimal (thermal stimulation). Leptospires developed in all media used and remained viable for 112 to 168 days (at 4-8° C incubation) in liquid media. The formation of cellular aggregate between Leptospira spp. and Aquaspirillum spp. was independent at the incubation temperature. These results suggest that Aquaspirillum spp. coexists with the genus Leptospira in surface waters, and their presence may indicate possible circulation of leptospires. Instituto de Patobiología Fil: Scialfa, Exequiel. Ministerio de Salud. División Zoonosis Rurales; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Agronomía; Argentina Fil: Videla, Yanina. Ministerio de Salud. División Zoonosis Rurales; Argentina. Comisión de Investigaciones Científicas de la Provincia de Buenos Aires; Argentina Fil: Grune Loffler, Sylvia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patobiología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fil: Quintana, Silvina. Instituto de Análisis Fares Taie; Argentina Fil: Aguirre, Pablo. Ministerio de Salud. División Zoonosis Rurales; Argentina Fil: Brihuega, Bibiana Felicitas. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patobiología; Argentina
- Published
- 2019
50. Cefepime and Amoxicillin Increase Metabolism and Enhance Caspofungin Tolerance of Candida albicans Biofilms
- Author
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Lucas Pereira de Alencar, Patrícia Bruna Leite Mendes, Rosana Serpa, Jonathas Sales de Oliveira, Marcos Fábio Gadelha Rocha, José Júlio Costa Sidrim, Antonio José de Jesus Evangelista, Raimunda Sâmia Nogueira Brilhante, Débora Castelo Branco de Souza Collares Maia, Reginaldo Gonçalves de Lima-Neto, Ana Raquel Colares de Andrade, Vandbergue Santos Pereira, and Rossana de Aguiar Cordeiro
- Subjects
Microbiology (medical) ,medicine.drug_class ,Cefepime ,Antibiotics ,lcsh:QR1-502 ,Microbiology ,lcsh:Microbiology ,biofilm ,03 medical and health sciences ,chemistry.chemical_compound ,Chitin ,β-lactam antibiotics ,Candida albicans ,medicine ,cefepime ,030304 developmental biology ,Amoxicilina ,Original Research ,0303 health sciences ,amoxicillin ,biology ,030306 microbiology ,Biofilm ,Amoxicillin ,biochemical phenomena, metabolism, and nutrition ,biology.organism_classification ,Corpus albicans ,Anti-Bacterial Agents ,chemistry ,Antibacterianos ,Caspofungin ,Biofilmes ,medicine.drug - Abstract
It is well known that prolonged antibiotic therapy alters the mucosal microbiota composition, increasing the risk of invasive fungal infection (IFI) in immunocompromised patients. The present study investigated the direct effect of β-lactam antibiotics cefepime (CEF) and amoxicillin (AMOX) on biofilm production by Candida albicans ATCC 10231. Antibacterials at the peak plasmatic concentration of each drug were tested against biofilms grown on polystyrene surfaces. Biofilms were evaluated for biomass production, metabolic activity, carbohydrate and protein contents, proteolytic activity, ultrastructure, and tolerance to antifungals. CEF and AMOX enhanced biofilm production by C. albicans ATCC 10231, stimulating biomass production, metabolic activity, viable cell counts, and proteolytic activity, as well as increased biovolume and thickness of these structures. Nevertheless, AMOX induced more significant changes in C. albicans biofilms than CEF. In addition, it was shown that AMOX increased the amount of chitin in these biofilms, making them more tolerant to caspofungin. Finally, it was seen that, in response to AMOX, C. albicans biofilms produce Hsp70 - a protein with chaperone function related to stressful conditions. These results may have a direct impact on the pathophysiology of opportunistic IFIs in patients at risk.
- Published
- 2019
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