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Having an insight into graphene and graphene derivatives such as graphene oxide, reduced graphene oxide and graphene quantum dots is necessary since it can help scientists to detect possible properties and features that could be useful when using these carbon materials in preparation of a nanocomposites. In recent years, graphene and its derivatives have attracted a lot of attention and been extensively applied in biosensors due to fascinating properties, such as large surface area, optical and magnetic properties, and high elasticity for the detection of microorganisms as they can be modified with some other materials such as macromolecules, oxide metals and metals to improve the electrochemical behaviour of the biosensor. In this review paper, biosensor design strategies based on graphene and its derivatives (graphene-based nanocomposites in biosensors) are described. Then their application for the detection of microorganisms including prions, viroids, viral and bacterial cells as well as fungi, protozoa, microbial toxins and even microbial sources of antibiotics is reviewed.

Background: Colorectal surgery is associated with the highest rate of surgical site infection (SSI). This study analyses the effectiveness of an interventional surveillance program on SSI rates after elective colorectal surgery. Material and methods: Cohort study showing temporal trends of SSI rates and Standardized Infection Ratio (SIR) in elective colorectal surgery over a 12-year period. Prospectively collected data of a national SSI surveillance program was analysed and the effect of specific interventions was evaluated. Patient and procedure characteristics, as well as SIR and SSI rates were stratified by risk categories and type of SSI analysed using stepwise multivariate logistic regression models. Results: In a cohort of 42,330 operations, overall cumulative SSI incidence was 16.31%, and organ-space SSI (O/S–SSI) was 8.59%. There was a 61.63% relative decrease in SSI rates (rho = -0.95804). The intervention which achieved the greatest SSI reduction was a bundle of 6 measures. SSI in pre-bundle period was 19.73% vs. 11.10% in post-bundle period (OR 1.969; IC 95% 1.860–2.085; p < 0.0001). O/S–SSI were 9.08% vs. 6.06%, respectively (OR 1.547; IC 95% 1.433–1.670; p < 0.0001). Median length of stay was 7 days, with a significant decrease over the studied period (rho = -0.98414). Mortality of the series was 1.08%, ranging from 0.35% to 2.0%, but a highly significant decrease was observed (rho = -0.67133). Conclusions: Detailed analysis of risk factors and postoperative infection in colorectal surgery allows strategies for reducing SSI incidence to be designed. An interventional surveillance program has been effective in decreasing SIR and SSI rates. © 2022 The Authors

Aim: Here, we evaluate the ddPCR platform using an evaluated qPCR-based diagnostic assay for the detection of Leishmania infection in Cutaneous Leishmaniasis patients. Methods: A standard curve of cultured Leishmania parasite material and clinical samples of CL patients were tested with ddPCR to determine the analytical and diagnostic performance. Results: The limit of detection of the assay on the ddPCR platform was much higher than the published limit of detection of the same assay on the qPCR platform (100 vs 1 parasites/mL, respectively). Conclusion: While the performance of this assay in ddPCR format was acceptable for research purposes, it is not sufficient for clinical diagnostic purposes. The assay is more suited to the qPCR platform. Keywords: Leishmania, ddPCR, Molecular diagnosis, Cutaneous Leishmaniasis

Leishmaniasis comprises a spectrum of parasitic diseases caused by protozoans of the genus Leishmania. Molecular tools have been widely employed for the detection of Leishmania due to its high sensitivity and specificity. However, the analytical performance of molecular platforms as PCR and real time PCR (qPCR) including a wide variety of molecular markers has never been evaluated. Herein, the aim was to evaluate the analytical performance of 4 PCR-based assays (designed on four different targets) and applied on conventional and real-time PCR platforms. We evaluated the analytical performance of conventional PCR and real time PCR, determining exclusivity and inclusivity, Anticipated Reportable Range (ARR), limit of detection (LoD) and accuracy using primers directed to kDNA, HSP70, 18S and ITS-1 targets. We observed that the kDNA was the most sensitive but does not meet the criterion of exclusivity. The HSP70 presented a higher LoD in conventional PCR and qPCR in comparison with the other markers (1 × 101 and 1 × 10-1 equivalent parasites/mL respectively) and had a higher coefficient of variation in qPCR. No statistically significant differences were found between the days of the test with the four molecular markers. The present study revealed that the 18S marker presented the best performance in terms of analytical sensitivity and specificity for the qPCR in the species tested (species circulating in Colombia). Therefore, we recommend to explore the analytical and diagnostic performance in future studies using a broader number of species across America. © 2017 León, Muñoz, Hernández, Ayala, Flórez, Teherán, Cubides and Ramírez.

SUMMARYAvian malaria is a vector transmitted disease caused byPlasmodiumand recent studies suggest that variation in its prevalence across avian hosts is correlated with a variety of ecological traits. Here we examine the relationship between prevalence and diversity ofPlasmodiumlineages in southeastern Amazonia and: (1) host ecological traits (nest location, nest type, flocking behaviour and diet); (2) density and diversity of avian hosts; (3) abundance and diversity of mosquitoes; and (4) season. We used molecular methods to detectPlasmodiumin blood samples from 675 individual birds of 120 species. Based on cytochromebsequences, we recovered 89 lineages ofPlasmodiumfrom 136 infected individuals sampled across seven localities.Plasmodiumprevalence was homogeneous over time (dry season and flooding season) and space, but heterogeneous among 51 avian host species. Variation in prevalence among bird species was not explained by avian ecological traits, density of avian hosts, or mosquito abundance. However,Plasmodiumlineage diversity was positively correlated with mosquito abundance. Interestingly, our results suggest that avian host traits are less important determinants ofPlasmodiumprevalence and diversity in southeastern Amazonia than in other regions in which they have been investigated.

Chagas disease is a zoonotic infection widely distributed in tropical and subtropical regions of America, including more than 50% of the Colombian territory. In the last years, an increase of outbreaks of acute Chagas disease has been observed in the east of the country due to environmental changes and mammal movements toward human settlements. Given the importance of dogs (Canis lupus familiaris) as reservoir hosts and sentinels of Trypanosoma cruzi infection across different regions of America, in this study we reported a serological and molecular detection of T. cruzi infection in 242 dogs from an endemic area of Meta department (East of Colombia), with recent emergence of acute Chagas disease outbreaks. The distribution of T. cruzi infection in dogs was not homogeneous, ranging from 0–41.4% and 0–5.1% in different sampling sectors, through serological (ELISA/IFAT) and molecular methods (conventional and real time PCR), respectively. Statistical analysis indicated that dog infection was associated with specific sampling sectors. Our results show a moderate seroprevalence of infection and active circulation of T. cruzi in dogs from this zone, which suggest areas with potential risk of infection to human that must be taken into consideration when Chagas disease control programs need to be implemented. © 2017 Elsevier B.V.

Interest in larval source management (LSM) as an adjunct intervention to control and eliminate malaria transmission has recently increased mainly because long-lasting insecticidal nets (LLINs) and indoor residual spray (IRS) are ineffective against exophagic and exophilic mosquitoes. In Amazonian Peru, the identification of the most productive, positive water bodies would increase the impact of targeted mosquito control on aquatic life stages. The present study explores the use of unmanned aerial vehicles (drones) for identifying Nyssorhynchus darlingi (formerly Anopheles darlingi) breeding sites with high-resolution imagery (~0.02m/pixel) and their multispectral profile in Amazonian Peru. Our results show that high-resolution multispectral imagery can discriminate a profile of water bodies where Ny. darlingi is most likely to breed (overall accuracy 86.73%- 96.98%) with a moderate differentiation of spectral bands. This work provides proof-of-concept of the use of high-resolution images to detect malaria vector breeding sites in Amazonian Peru and such innovative methodology could be crucial for LSM malaria integrated interventions., Author summary The most efficient malaria vector in the Latin American region is Nyssorhynchus darlingi (formerly Anopheles darlingi). In Amazonian Peru, where malaria is endemic, Ny. darlingi feeds both indoors and outdoors (endophagy, exophagy), depending on the local environment, and rests outdoors (exophily). LLINs and IRS, the most common tools employed for vector control, target endophagic and endophilic mosquitoes. Thus, they are only partially effective against Ny. darlingi. Control of the aquatic stages of vector mosquitoes, larval source management (LSM), targets the most productive breeding sites nearest to human habitation. In four riverine communities, we used drones with high-resolution imagery as a key initial step to analyze water bodies within the estimated flight range of Ny. darlingi, ~ 1 km. We found distinctive spectral profiles for water bodies that were positive versus negative for Ny. darlingi. The methodology and analysis reported here provide the basis for testing whether LSM can be combined successfully with LLINs and IRS to contribute to the elimination of transmission in malaria hotspots in the Amazon.

Fe de erratas. The fifth author's name is spelled incorrectly. The correct name is: Carlos A. Valencia-Hernandez. The correct citation is: Hernández C, Cucunubá Z, Flórez C, Olivera M, Valencia-Hernandez C.A., Zambrano P, et al. (2016) Molecular Diagnosis of Chagas Disease in Colombia: Parasitic Loads and Discrete Typing Units in Patients from Acute and Chronic Phases. PLoS Negl Trop Dis 10(9): e0004997. doi: 10.1371/journal.pntd.0004997 Background: The diagnosis of Chagas disease is complex due to the dynamics of parasitemia in the clinical phases of the disease. The molecular tests have been considered promissory because they detect the parasite in all clinical phases. Trypanosoma cruzi presents significant genetic variability and is classified into six Discrete Typing Units TcI-TcVI (DTUs) with the emergence of foreseen genotypes within TcI as TcIDom and TcI Sylvatic. The objective of this study was to determine the operating characteristics of molecular tests (conventional and Real Time PCR) for the detection of T. cruzi DNA, parasitic loads and DTUs in a large cohort of Colombian patients from acute and chronic phases. Methodology/Principal Findings: Samples were obtained from 708 patients in all clinical phases. Standard diagnosis (direct and serological tests) and molecular tests (conventional PCR and quantitative PCR) targeting the nuclear satellite DNA region. The genotyping was performed by PCR using the intergenic region of the mini-exon gene, the 24Sa, 18S and A10 regions. The operating capabilities showed that performance of qPCR was higher compared to cPCR. Likewise, the performance of qPCR was significantly higher in acute phase compared with chronic phase. The median parasitic loads detected were 4.69 and 1.33 parasite equivalents/mL for acute and chronic phases. The main DTU identified was TcI (74.2%). TcIDom genotype was significantly more frequent in chronic phase compared to acute phase (82.1% vs 16.6%). The median parasitic load for TcIDom was significantly higher compared with TcI Sylvatic in chronic phase (2.58 vs.0.75 parasite equivalents/ml). Conclusions/Significance: The molecular tests are a precise tool to complement the standard diagnosis of Chagas disease, specifically in acute phase showing high discriminative power. However, it is necessary to improve the sensitivity of molecular tests in chronic phase. The frequency and parasitemia of TcIDom genotype in chronic patients highlight its possible relationship to the chronicity of the disease. © 2016 Hernández et al.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:25:55Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:41:46Z : No. of bitstreams: 1 2-s2.0-79959529864.pdf: 404547 bytes, checksum: 3dd112d0ead1a181b75b1f2328b2f7f9 (MD5) Made available in DSpace on 2014-05-27T11:25:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-06-28 A água é a matéria-prima mais utilizada na produção de várias formas farmacêuticas, sendo um constituinte da própria formulação e exigindo para tal uma série de especificações físico-químicas e microbiológicas. Além disso, é um insumo de utilização imprescindível para testes laboratoriais e procedimentos de limpeza de equipamentos e utensílios. O presente trabalho teve como objetivo verificar o grau de contaminação química e microbiana em água purificada utilizada em farmácias magistrais da região de São José do Rio Preto, SP. As coletas foram realizadas segundo recomendações da USP Pharmacopeia, com os devidos cuidados de assepsia, e as amostras encaminhadas imediatamente ao laboratório de controle de qualidade. Foram analisados vários parâmetros físico-químicos, tais como aspecto, pH, condutividade, resíduo por evaporação, amônia, cálcio, cloreto, metais pesados, sulfato e substâncias oxidáveis, além de parâmetros microbiológicos, como contagem total de aeróbios e pesquisa de coliformes totais e termotolerantes e Pseudomonas aeruginosa. Os resultados indicaram alguns parâmetros de não conformidade: em 10% das amostras analisadas para o pH e pesquisa de impurezas inorgânicas, em 17% para condutividade, em 14% para substâncias oxidáveis e em 20% para análise microbiológica, ressaltando a necessidade de maior rigor na produção e qualidade da água purificada produzida e/ou armazenada nesses estabelecimentos farmacêuticos. Water is the raw material used most in the production of diverse pharmaceutical forms and, being a constituent of the formulation itself, is subject to a number of physico-chemical and microbiological specifications. In addition, it is indispensable for laboratory tests and the cleaning of equipment and apparatus. The aim of this study was to ascertain the degree of physicochemical and microbiological contamination of purified water used in compounding pharmacies in the city of São José do Rio Preto, SP, Brazil. Samples were taken as recommended in the USP Pharmacopeia, with careful aseptic technique, and sent immediately the to quality control laboratory. Physicochemical properties were analyzed, including appearance, pH, conductivity, residue after evaporation, ammonia, calcium, chloride, heavy metals, sulfate and oxidizable substances, and microbiological tests were performed: total aerobic microbial count and detection of total and thermotolerant coliforms and Pseudomonas aeruginosa. Results showed that some parameters did not conform to the standards, especially pH, conductivity, inorganic impurities, oxidizable substances and microbiological test data, in 10%, 17%, 10%, 14% and 20% of the analyzed samples, respectively, This points to the need for greater care in the production and/or storage of purified water in these pharmaceutical establishments. Departamento de Fármacos e Medicamentos Faculdade de Ciências Farmacêuticas UNESP, Rodovia Araraquara-Jaú, km 1, Araraquara, SP, CEP 14801-902 Departamento de Fármacos e Medicamentos Faculdade de Ciências Farmacêuticas UNESP, Rodovia Araraquara-Jaú, km 1, Araraquara, SP, CEP 14801-902

The antimicrobial activity of propolis against some gram-positive and gram-negative bacteria and its chemical composition were evaluated by the method of agar-well diffusion and GC-MS, respectively. Some typical compounds samples were identified in the propolis samples. Principal component analysis revealed that the chemical composition of propolis samples was distinct based on the geographical location of the samples. It was found that flavonoids, chrysin, flavanones and cinnamic acid were the predominant compounds in the propolis samples. © 2006 Academic Journals.

Background: Citrus Huanglongbing (HLB) is the most devastating bacterial citrus disease worldwide. Three Candidatus Liberibacter species are associated with different forms of the disease: Candidatus Liberibacter asiaticus, Candidatus Liberibacter americanus and Candidatus Liberibacter africanus. Amongst them, Candidatus Liberibacter asiaticus is the most widespread and economically important. These Gram-negative bacterial plant pathogens are phloem-limited and vectored by citrus psyllids. The current management strategy of HLB is based on early and accurate detection of Candidatus Liberibacter asiaticus in both citrus plants and vector insects. Nowadays, real time PCR is the method of choice for this task, mainly because of its sensitivity and reliability. However, this methodology has several drawbacks, namely high equipment costs, the need for highly trained personnel, the time required to conduct the whole process, and the difficulty in carrying out the detection reactions in field conditions. Results: A recent DNA amplification technique known as Loop Mediated Isothermal Amplification (LAMP) was adapted for the detection of Candidatus Liberibacter asiaticus. This methodology was combined with a Lateral Flow Dipstick (LFD) device for visual detection of the resulting amplicons, eliminating the need for gel electrophoresis. The assay was highly specific for the targeted bacterium. No cross-reaction was observed with DNA from any of the other phytopathogenic bacteria or fungi assayed. By serially diluting purified DNA from an infected plant, the sensitivity of the assay was found to be 10 picograms. This sensitivity level was proven to be similar to the values obtained running a real time PCR in parallel. This methodology was able to detect Candidatus Liberibacter asiaticus from different kinds of samples including infected citrus plants and psyllids. Conclusions: Our results indicate that the methodology here reported constitutes a step forward in the development of new tools for the management, control and eradication of this destructive citrus disease. This system constitutes a potentially field-capable approach for the detection of the most relevant HLB-associated bacteria in plant material and psyllid vectors. Fil: Rigano, Luciano Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencias y Tecnología "Dr. Cesar Milstein"; Argentina. University of Otago. Department of Microbiology and Immunology; Nueva Zelanda Fil: Malamud, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencias y Tecnología "Dr. Cesar Milstein"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina Fil: Orce, Ingrid Georgina. Instituto de Tecnología Agroindustrial del Noroeste Argentino. Estación Experimental Agroindustrial Obispo Colombres; Argentina Fil: Filippone, María Paula. Instituto de Tecnología Agroindustrial del Noroeste Argentino. Estación Experimental Agroindustrial Obispo Colombres; Argentina Fil: Marano, Maria Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; Argentina Fil: Do Amaral, Alexandre Morais. Ministerio Da Agricultura Pecuaria E Abastecimento de Brasil. Empresa Brasileira de Pesquisa Agropecuaria; Brasil Fil: Castagnaro, Atilio Pedro. Instituto de Tecnología Agroindustrial del Noroeste Argentino. Estación Experimental Agroindustrial Obispo Colombres; Argentina Fil: Vojnov, Adrian Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencias y Tecnología "Dr. Cesar Milstein"; Argentina