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Sidi Mohammed Lahbib Seddiki,1 Zahia Boucherit-Otmani,1 Kebir Boucherit,1 Souad Badsi-Amir,2 Mourad Taleb,3 Dennis Kunkel41Laboratory: Antifungal Antibiotic, Physico-Chemical Synthesis and Biological Activity, University of Tlemcen, Algeria; 2Department of Anesthesiology, 3Department of Epidemiology, University Hospital of Sidi Bel Abbes, Algeria; 4Dennis Kunkel Microscopy Inc, Kailua, HI, USAAbstract: Nosocomial candidiasis remains a potential risk in intensive care units (ICUs), wherein Candida albicans is most responsible for its occurrence. Equally, non-C. albicans species, especially C. glabrata, are also involved. These infections are frequently associated with biofilms that contaminate medical devices, such as catheters. These biofilms constitute a significant clinical problem, and cause therapeutic failures, because they can escape the immune response and considerably decrease sensitivity to antifungal therapy. The diagnosis of catheter-related candidiasis is difficult; however, the differentiation between an infection of the catheter (or other medical implant) and a simple contamination is essential to start an antifungal treatment. Among the methods used for this type of study is the Brun-Buisson method, but this method only examines the infectivity of catheters caused by bacteria. For this reason, we wanted to adapt this method to the yeast cells of Candida spp. To assess the various types of infectivity of catheters (contamination, colonization, or infection) and their corresponding rates, as well as the responsible yeast species, we conducted our study, between February 2011 and January 2012, in the ICU at the University Hospital Center of Sidi Bel Abbes, Algeria; during this study, we took photographic images of the tongue of one patient and of that patient's implanted orobronchial catheter. In addition, catheters contaminated by C. albicans biofilms were observed by scanning electron microscopy.Keywords: ICU, contamination, colonization, infection

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The aim of this work is to study the effect of the physicochemical environment on in vivo distribution of amphotericin B, which was prepared in acetic acid/acetate buffer pH 5.4 at a concentration of 10-4 M. Rats were injected intraperitoneally with this antifungal solution at the doses of 1, 2 or 5 mg/kg body weight. At predefined time, amphotericin B from tissues and plasma was extracted and analysed using the second derivative spectrophotometry methodology. The level of amphotericin B in tissues and plasma depended on the administered dose and decreased over a period of time. The highest concentrations were found in the spleen, followed by the liver, but were lower in kidneys and plasma. Amphotericin B was accumulated in the intraperitoneal cavity (the peritoneal adipose tissue) in large quantities proportional to the dose administered intraperitoneally. This formulation has the advantage of being easy to prepare and inexpensive, it seems very promising for the treatment of fungal infections of spleen and peritoneal cavity. [ABSTRACT FROM AUTHOR]

Providing a live data monitoring of raptor abundances and spatial localization of their most important nesting areas is very helpful in building a strong future study and applying a sound strategy for effective safeguarding of these emblematic species. Using geographic information system (GIS) and global positioning system (GPS) techniques, we investigated spatial patterns of raptors distribution in the northeastern areas of Algeria during two consecutive breeding seasons (2014 and 2015). The total area sampled (31,000 km2) host diverse raptor species (14 species), among them, the threatened species Egyptian vulture (Neophron percnopterus; 108 individuals and 19 active nests) and red-footed falcon (Falco vespertinus; 12individuals). The value of the region is attested by the presence of an abundant population of nesting black kite (Milvus migrans; 337 individuals). The large-scale spatial analyses of the studied region illustrate certain similarities in nesting habitat selection among raptors. Almost all species (90% of 209 nests detected) preferred to nest within multispecies assemblages (20 raptor assemblages found) and occupied altitudinal rocky cliffs across the inland region (semi-arid zones) rather than coastal region (sub-humid zones). Among all raptor species, exclusively, the common kestrel (Falco tinnunculus) is relatively synanthropic, because it was found to breed within cities (tolerate human activities). The raptor community in the coastal versus inland regions differed by 14%. The latter area seems to be more preferred in nest building, probably consequence of their semi-arid bioclimatic and landscapes characteristics, where high elevations and grasslands forming mosaics with Oak, Alpine, and Cedar forests are patchily distributed. The study is a first mapping database of important nesting sites dispatched across the northeastern areas of Algeria, and it can be effectively used in future complementary researches that aim to elucidate environmental factors that affect raptors life cycle.

Copyright of Phytothérapie is the property of John Libbey Eurotext Ltd. 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.)

Copyright of Journal of Medical Mycology / Journal de Mycologie Médicale is the property of Elsevier B.V. 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.)

Cystic fibrosis patients' lungs are chronically colonized by multiple microbial species capable of forming biofilms. This study aimed to characterize the polymicrobial biofilm formed by Candida spp. and S. aureus, co-isolated from sputum samples of cystic fibrosis patients regarding microbial density, metabolic activity, and structure. 67 samples from 28 patients were collected with a 96% alteration rate. 34% showed alterations by both Candida spp. and Gram-positive bacteria, predominantly Candida spp. and S. aureus in 77% of cases, accounting for 6 associations. Biofilm biomass was quantified using the crystal violet assay, and metabolic activity was assessed using the MTT reduction assay. Scanning electron microscopy analyzed the C. tropicalis/S. aureus24 biofilm architecture. Candida spp. isolates demonstrated the ability to form mixed biofilms with S. aureus. The C. tropicalis/S. aureus24 association exhibited the highest production of biofilm and metabolic activity, along with the C. albicans17/C. rugosa/S. aureus7 in both single and mixed biofilms., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Cystic fibrosis (CF) is an inherited disease that results from mutations in the gene responsible for the cystic fibrosis transmembrane conductance regulator (CFTR). The airways become clogged with thick, viscous mucus that traps microbes in respiratory tracts, facilitating colonization, inflammation and infection. CF is recognized as a biofilm-associated disease, it is commonly polymicrobial and can develop in biofilms. This review discusses Candida spp. and both Gram-positive and Gram-negative bacterial biofilms that affect the airways and cause pulmonary infections in the CF context, with a particular focus on mixed-species biofilms. In addition, the review explores the intricate interactions between fungal and bacterial species within these biofilms and elucidates the underlying molecular mechanisms that govern their dynamics. Moreover, the review addresses the multifaceted issue of antimicrobial resistance in the context of CF-associated biofilms. By synthesizing current knowledge and research findings, this review aims to provide insights into the pathogenesis of CF-related infections and identify potential therapeutic approaches to manage and combat these complex biofilm-mediated infections., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Cystic fibrosis (CF) is a rare disease in Algeria, and its prognosis is poor in developing countries. The clinical and demographic knowledge of Algerian pediatric patients diagnosed with CF is incomplete due to the nonexistence of a national medical registry. Hence, the present study is the first Algerian multicentre study on CF., Methods: This retrospective study was conducted in western Algeria. Over 1 year, the study included all pediatric patients with a confirmed diagnosis of CF in the pediatric hospital of Oran. Patient characteristics, clinical manifestations, and the prescribed treatment were reported., Results: Thirty-four children (16 boys and 18 girls) participated in this study. Only 15 were diagnosed before the age of 6 months. The sweat chloride test was positive in all patients. Respiratory manifestations were found in all patients, chronic diarrhoea in 29 of them, and growth retardation in 10. Moreover, 25 (73.5%) had low to low intermediate socioeconomic levels. After diagnosis, respiratory complications marked the evolution of the 34 patients, with bronchial congestion observed in 33 of them, while 10 (29.4%) patients presented severe bronchopneumonia and 4 (11.8%) were affected by asthma. Consequently,  three (8.8%) died at an average age of 9 years mainly because of respiratory failure., Conclusion: The prognosis of CF is poor in Algeria compared to other developed countries due to the longer diagnostic delay and limited therapeutic alternatives. This representative subset of Algerian pediatric patients with CF will serve as a reference for future studies on CF in Algeria., (© 2024 Wiley Periodicals LLC.)

Fungal-bacterial infections are being increasingly recognized in clinical settings, and the interaction between these species in polymicrobial biofilms often lead to infections that are highly resistant to treatment. In this in vitro study, we analyzed the formation of mixed biofilms using clinically isolated Candida parapsilosis and Enterobacter cloacae. Additionally, we assessed the potential of conventional antimicrobials, both alone and in combination, for treating polymicrobial biofilms built by these human pathogens. Our results demonstrate that C. parapsilosis and E. cloacae are capable of forming mixed biofilms, as confirmed by scanning electron microscopy. Interestingly, we found that colistin alone or in combination with antifungal drugs was highly effective reducing up to 80% of the total biomass of polymicrobial biofilms., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background and Purpose: Amphotericin B (AmB) is the standard treatment for systemic fungal infections; however, the formation of reactive oxygen species reduces the efficacy and stability of this molecule. The present study aimed to evaluate the effect of the combination of AmB with ascorbic acid and α-tocopherol on its autoxidation and antifungal activity., Materials and Methods: The antifungal activity against Candida albicans was evaluated by the viable cell counting method and checking their morphological changes with a scanning electron microscope. Monomer state of AmB was assessed by scanning the UV absorbance in the range of 300-450 nm and the lipid peroxidation was measured using quantification of thiobarbituric acid reactive-substances (TBARS)., Results: Based on the findings, the addition of ascorbic acid (3×10 2 µg/mL) and α-tocopherol (16 µg/mL) to the reaction medium of AmB increased its antifungal  activity while maintaining its molecular stability. Moreover, the level of TBARS formed in the reaction medium of AmB was significantly reduced after combination  with ascorbic acid and α-tocopherol., Conclusion: Given their availability, their anti-free radical activity, and their low toxicity, the incorporation of ascorbic acid and α-tocopherol into the reaction medium of AmB seems to be a promising approach to obtain an effective antifungal formulation., (Copyright: © 2021, Published by Mazandaran University of Medical Sciences on behalf of Iranian Society of Medical Mycology and Invasive Fungi Research Center.)

The authors wish to make the following correction to this paper [1] [...].

Candida albicans is one of the most common human fungal pathogens and represents the most important cause of opportunistic mycoses worldwide. Surgical devices including catheters are easily contaminated with C. albicans via its formation of drug-resistant biofilms. In this study, amphotericin-B-resistant C. albicans strains were isolated from surgical devices at an intensive care center. The objective of this study was to develop optimized effective inhibitory treatment of resistant C. albicans by terpenoids, known to be produced naturally as protective signals. Endogenously produced farnesol by C. albicans yeast and plant terpenoids, carvacrol, and cuminaldehyde were tested separately or in combination on amphotericin-B-resistant C. albicans in either single- or mixed-infections. The results showed that farnesol did not inhibit hyphae formation when associated with bacteria. Carvacrol and cuminaldehyde showed variable inhibitory effects on C. albicans yeast compared to hyphae formation. A combination of farnesol with carvacrol showed synergistic inhibitory activities not only on C. albicans yeast and hyphae, but also on biofilms formed from single- and mixed-species and at reduced doses. The combined terpenoids also showed biofilm-penetration capability. The aforementioned terpenoid combination will not only be useful in the treatment of different resistant Candida forms, but also in the safe prevention of biofilm formation.

Aims: The aim of this study was to evaluate the presence of yeasts in dental chair unit waterlines (DCUWLs) and to test their ability to form biofilms., Materials and Methods: Eighteen dental waterlines were analysed by culture in liquid Sabouraud in order to allow the quantification and the purification of isolated yeasts from their internal surfaces. All isolates were identified by standard laboratory procedures, including CHROMagar Candida medium for orientation, commercial yeast identification system Api Candida, MALDI-TOF MS and DNA sequencing. To evaluate their kinetics of antifungal susceptibility during different phases of biofilm formation, these yeasts were subjected to three antifungal agents., Results: From the 18 DCUWLs studied, 10 were altered (55.56%). Eleven strains of Candida sp. [Candida albicans (2), Candida guilliermondii (5) and Candida glabrata (4)] and two species of non-Candida; Rhodotorula spp. (1) and Trichosporon spp. (2) were identified. The majority of yeasts in planktonic form were susceptible to amphotericin B, caspofungin and voriconazole, except C. albicans was resistant to voriconazole. In the biofilm form, caspofungin was the most effective antifungal agent for all isolated strains. For the other antifungal agents, sessile cells were resistant., Conclusion: Several types of yeasts were identified; the most frequently isolated genus was Candida. The majority of these yeasts had the ability to form biofilms and resisted antifungal agents used in this study., (© 2018 FDI World Dental Federation.)

Cosmetics, like any product containing water and organic/inorganic compounds, require preservation against microbial contamination to guarantee consumer’s safety and to increase their shelf-life. The microbiological safety has as main goal of consumer protection against potentially pathogenic microorganisms, together with the product’s preservation resulting from biological and physicochemical deterioration. This is ensured by chemical, physical, or physicochemical strategies. The most common strategy is based on the application of antimicrobial agents, either by using synthetic or natural compounds, or even multifunctional ingredients. Current validation of a preservation system follow the application of good manufacturing practices (GMPs), the control of the raw material, and the verification of the preservative effect by suitable methodologies, including the challenge test. Among the preservatives described in the positive lists of regulations, there are parabens, isothiasolinone, organic acids, formaldehyde releasers, triclosan, and chlorhexidine. These chemical agents have different mechanisms of antimicrobial action, depending on their chemical structure and functional group’s reactivity. Preservatives act on several cell targets; however, they might present toxic effects to the consumer. Indeed, their use at high concentrations is more effective from the preservation viewpoint being, however, toxic for the consumer, whereas at low concentrations microbial resistance can develop.

Yeasts can adhere to medical implants and cause infections responsible for high morbidity and mortality among hospitalized patients. The objective of this study is to investigate the infectivity on peripheral vascular catheters collected from general surgery and cardiology in University Hospital of Tlemcen. The results showed that from 29 samples altered by yeast, 35 Candida sp. strains were isolated. However, Candida albicans is the most isolated species in an infectious context. Risk factors that accompanied the infections are the duration of implantation, male gender, and bacterial presence., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

The Candida yeasts are the fourth leading cause of death from systemic infections, the risk may increase when the infection also involves bacteria. Yeasts and bacteria can adhere to medical implants, such as peripheral vascular catheters, and form a multicellular structures called "mixed biofilms" more resistant to antimicrobials agents. However, the formation of mixed biofilms on implants leads to long-term persistent infections because they can act as reservoirs of pathogens that have poorly understood interactions., (Copyright © 2016 Elsevier Masson SAS. All rights reserved.)

Background: Candidemia are the most common fungal infections in hospitals. However, the catheters are subject to be altered by Candida biofilms which increase the risk of invasive nosocomial infections due to the high resistance to antifungal agents. Therefore, the minimum inhibitory concentrations of planktonic (MIC) and sessile cells (CIMS) were evaluated., Methods: To review the in vivo biofilms structures of Candida sp. formed on the inner and/or external surfaces of collected catheters, we used scanning electron microscopy (SEM). The level of biofilm resistance was assessed against two conventional antifungal agents: amphotericin B (AmB), which belongs to the class of polyenes, and fluconazole (FLZ) which is an azole., Results: The SEM observation of biofilms of Candida sp. reveals complex structures. Compared to MICs, the calculation of CIMS showed an increase of 32 times with AmB and of 128 times with FLZ., Conclusion: Catheters offer an ideal surface to Candida sp. to form biofilms. This complex structure induces the increase of the resistance of sessile cells against two antifungal agents, AmB and FLZ., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)