-
FEMS Microbiology Reviews Mar 2012The incidence of infections caused by Candida species (candidosis) has increased considerably over the past three decades, mainly due to the rise of the AIDS epidemic,... (Review)
Review
The incidence of infections caused by Candida species (candidosis) has increased considerably over the past three decades, mainly due to the rise of the AIDS epidemic, an increasingly aged population, higher numbers of immunocompromised patients and the more widespread use of indwelling medical devices. Candida albicans is the main cause of candidosis; however, non-C. albicans Candida (NCAC) species such as Candida glabrata, Candida tropicalis and Candida parapsilosis are now frequently identified as human pathogens. The apparent increased emergence of these species as human pathogens can be attributed to improved identification methods and also associated with the degree of diseases of the patients, the interventions that they were subjected and the drugs used. Candida pathogenicity is facilitated by a number of virulence factors, most importantly adherence to host surfaces including medical devices, biofilm formation and secretion of hydrolytic enzymes (e.g. proteases, phospholipases and haemolysins). Furthermore, despite extensive research to identify pathogenic factors in fungi, particularly in C. albicans, relatively little is known about NCAC species. This review provides information on the current state of knowledge on the biology, identification, epidemiology, pathogenicity and antifungal resistance of C. glabrata, C. parapsilosis and C. tropicalis.
Topics: Animals; Antifungal Agents; Candida; Candida glabrata; Candida tropicalis; Candidiasis; Drug Resistance, Fungal; Humans
PubMed: 21569057
DOI: 10.1111/j.1574-6976.2011.00278.x -
Virulence Dec 2022Antifungal resistance to pathogens increases morbidity and mortality of immunosuppressive patients, an emerging crisis worldwide. Understanding the prevalence and... (Review)
Review
Antifungal resistance to pathogens increases morbidity and mortality of immunosuppressive patients, an emerging crisis worldwide. Understanding the prevalence and antifungal susceptibility pattern is necessary to control and treat candidiasis. We aimed to systematically analyse the susceptibility profiles of species published in the last ten years (December 2011 to December 2021) from mainland China. The studies were collected from PubMed, Google Scholar, and Science Direct search engines. Out of 89 included studies, a total of 44,716 isolates were collected, mainly comprising (49.36%), (21.89%), (13.92%), and (11.37%). The lowest susceptibility was detected for azole group; fluconazole susceptibilities against , and were 93.25%, 91.6%, 79.4%, 77.95%, 76%, 50%, and 0% respectively. Amphotericin B and anidulafungin were the most susceptible drugs for all species. Resistance to azole was mainly linked with mutations in , and genes. Mutation in and in and causing resistance to echinocandins was stated in two studies. Gaps in the studies' characteristics were detected, such as 79.77%, 47.19 %, 26.97%, 7.86%, and 4.49% studies did not mention the mortality rates, age, gender, breakpoint reference guidelines, and fungal identification method, respectively. The current study demonstrates the overall antifungal susceptibility pattern of species, gaps in surveillance studies and risk-reduction strategies that could be supportive in candidiasis therapy and for the researchers in their future studies.
Topics: Humans; Amphotericin B; Anidulafungin; Antifungal Agents; Azoles; Candida; Candida albicans; Candida glabrata; Candida parapsilosis; Candida tropicalis; Candidiasis; Echinocandins; Fluconazole; Microbial Sensitivity Tests
PubMed: 36120738
DOI: 10.1080/21505594.2022.2123325 -
Frontiers in Cellular and Infection... 2021is one of the most common opportunistic yeast pathogens of humans, especially prevalent in tropical and subtropical regions. This yeast has broad ecological... (Review)
Review
is one of the most common opportunistic yeast pathogens of humans, especially prevalent in tropical and subtropical regions. This yeast has broad ecological distributions, can be found in both terrestrial and aquatic ecosystems, including being associated with a diversity of trees, animals, and humans. Evolutionary theory predicts that organisms thriving in diverse ecological niches likely have efficient mechanisms to generate genetic diversity in nature. Indeed, abundant genetic variations have been reported in natural populations (both environmental and clinical) of . However, at present, our understanding on how genetic diversity is generated in natural population remains controversial. In this paper, I review the current understanding on the potential modes of reproduction in . I describe expectations of the three modes of reproduction (sexual, parasexual, and asexual) and compare them with the observed genotypic variations in natural populations. Though sexual and parasexual reproduction cannot be excluded, the analyses suggest asexual reproduction alone could explain all the observations reported so far. The results here have implications for understanding the evolution and epidemiology of and other related human fungal pathogens.
Topics: Animals; Candida tropicalis; Ecosystem; Fungi; Humans; Reproduction
PubMed: 34760719
DOI: 10.3389/fcimb.2021.751676 -
Frontiers in Microbiology 2017has emerged as one of the most important species. It has been widely considered the second most virulent species, only preceded by . Besides, this species has been... (Review)
Review
has emerged as one of the most important species. It has been widely considered the second most virulent species, only preceded by . Besides, this species has been recognized as a very strong biofilm producer, surpassing in most of the studies. In addition, it produces a wide range of other virulence factors, including: adhesion to buccal epithelial and endothelial cells; the secretion of lytic enzymes, such as proteinases, phospholipases, and hemolysins, bud-to-hyphae transition (also called morphogenesis) and the phenomenon called phenotypic switching. This is a species very closely related to and has been easily identified with both phenotypic and molecular methods. In addition, no cryptic sibling species were yet described in the literature, what is contradictory to some other medically important species. is a clinically relevant species and may be the second or third etiological agent of candidemia, specifically in Latin American countries and Asia. Antifungal resistance to the azoles, polyenes, and echinocandins has already been described. Apart from all these characteristics, has been considered an osmotolerant microorganism and this ability to survive to high salt concentration may be important for fungal persistence in saline environments. This physiological characteristic makes this species suitable for use in biotechnology processes. Here we describe an update of , focusing on all these previously mentioned subjects.
PubMed: 29081766
DOI: 10.3389/fmicb.2017.01927 -
Frontiers in Fungal Biology 2022Antifungal resistance in humans, animals, and the environment is an emerging problem. Among the different fungal species that can develop resistance, is ubiquitous and... (Review)
Review
Antifungal resistance in humans, animals, and the environment is an emerging problem. Among the different fungal species that can develop resistance, is ubiquitous and causes infections in animals and humans. In Asia and some Latin American countries, is among the most common species related to candidemia, and mortality rates are usually above 40%. Fluconazole resistance is especially reported in Asian countries and clonal spread in humans and the environment has been investigated in some studies. In Brazil, high rates of azole resistance have been found in animals and the environment. Multidrug resistance is still rare, but recent reports of clinical multidrug-resistant isolates are worrisome. The molecular apparatus of antifungal resistance has been majorly investigated in clinical isolates, revealing that this species can develop resistance through the conjunction of different adaptative mechanisms. In this review article, we summarize the main findings regarding antifungal resistance and through an "One Health" approach.
PubMed: 37746212
DOI: 10.3389/ffunb.2022.957021 -
Antimicrobial Resistance and Infection... Mar 2021Candida tropicalis (C. tropicalis) is an important opportunistic pathogenic Candida species that can cause nosocomial infection. In this study, we analyzed the...
BACKGROUND
Candida tropicalis (C. tropicalis) is an important opportunistic pathogenic Candida species that can cause nosocomial infection. In this study, we analyzed the distribution and drug susceptibility of C. tropicalis and the relationship between ERG11 and UPC2 expression and resistance to azole antifungal agents.
METHODS
C. tropicalis was cultured and identified by Sabouraud Agar Medium, CHROM Agar Candida and ATB tests (Bio-Mérieux, France). Total RNA was extracted from the collected strains, and the ERG11 and UPC2 mRNA expression levels were analyzed by quantitative real-time PCR.
RESULTS
In total, 2872 clinical isolates of Candida, including 319 strains of C. tropicalis, were analyzed herein; they were mainly obtained from the Departments of Respiratory Medicine and ICU. The strains were predominantly isolated from airway secretion samples, and the detection trend in four years was mainly related to the type of department and specimens. The resistance rates of C. tropicalis to fluconazole, itraconazole and voriconazole had been increasing year by year. The mRNA expression levels of ERG11 and UPC2 in the fluconazole-resistant group were significantly higher than they were in the susceptible group. In addition, there was a significant positive linear correlation between these two genes in the fluconazole-resistant group.
CONCLUSIONS
Overexpression of the ERG11 and UPC2 genes in C. tropicalis could increase resistance to azole antifungal drugs. The routine testing for ERG11 and UPC2 in high-risk patients in key departments would provide a theoretical basis for the rational application of azole antifungal drugs.
Topics: Antifungal Agents; Azoles; Candida tropicalis; China; Drug Resistance, Fungal; Fluconazole; Fungal Proteins; Humans; Itraconazole; Voriconazole
PubMed: 33722286
DOI: 10.1186/s13756-021-00890-2 -
The Libyan Journal of Medicine 2014Volatile oils obtained from lemon grass [Cymbopogon citratus (DC.) Stapf, Poaceae family] are used in traditional medicine as remedies for the treatment of various...
BACKGROUND
Volatile oils obtained from lemon grass [Cymbopogon citratus (DC.) Stapf, Poaceae family] are used in traditional medicine as remedies for the treatment of various diseases.
AIMS
In the present study, lemon grass essential oil (LGEO) was evaluated for its in vivo topical and oral anti-inflammatory effects, and for its in vitro antifungal activity using both liquid and vapor phases.
METHODS
The chemical profile of LGEO as determined by gas chromatography-mass spectrometry analysis revealed two major components: geranial (42.2%), and neral (31.5%). The antifungal activity of LGEO was evaluated against several pathogenic yeasts and filamentous fungi using disc diffusion and vapor diffusion methods.
RESULTS
LGEO exhibited promising antifungal effect against Candida albicans, C. tropicalis, and Aspergillus niger, with different inhibition zone diameters (IZDs) (35-90 mm). IZD increased with increasing oil volume. Significantly, higher anti-Candida activity was observed in the vapor phase. For the evaluation of the anti-inflammatory effect, LGEO (10 mg/kg, administered orally) significantly reduced carrageenan-induced paw edema with a similar effect to that observed for oral diclofenac (50 mg/kg), which was used as the positive control. Oral administration of LGEO showed dose-dependent anti-inflammatory activity. In addition, topical application of LGEO in vivo resulted in a potent anti-inflammatory effect, as demonstrated by using the mouse model of croton oil-induced ear edema. To our knowledge, this is the first such report to be published. The topical application of LGEO at doses of 5 and 10 µL/ear significantly reduced acute ear edema induced by croton oil in 62.5 and 75% of the mice, respectively. In addition, histological analysis clearly confirmed that LGEO inhibits the skin inflammatory response in animal models.
CONCLUSION
RESULTS of the present study indicate that LGEO has a noteworthy potential for the development of drugs for the treatment of fungal infections and skin inflammation that should be explored in future studies.
Topics: Animals; Anti-Inflammatory Agents; Antifungal Agents; Aspergillus niger; Candida albicans; Candida tropicalis; Cymbopogon; Ear; Edema; Female; Foot; Gas Chromatography-Mass Spectrometry; Male; Medicine, Traditional; Mice; Oils, Volatile; Phytotherapy; Plant Extracts; Plant Oils
PubMed: 25242268
DOI: 10.3402/ljm.v9.25431 -
Canadian Journal of Microbiology Jun 2023is among the most important species in terms of epidemiology, virulence and resistance. Considering the increase in incidence and high rates of mortality... (Review)
Review
is among the most important species in terms of epidemiology, virulence and resistance. Considering the increase in incidence and high rates of mortality associated with this species, knowledge of its adhesion and biofilm formation abilities is needed. These traits determine the persistence and survival of yeast on different indwelling medical devices and host sites. is among the most adherent species, and it has been described as a strong biofilm producer. Environmental factors, phenotypic switching and quorum sensing molecules can affect adhesion and biofilm growth. can form sexual biofilms, which are promoted by mating pheromones. biofilms are regulated by a wide and complex network of genes and signaling pathways that are currently poorly understood. Morphological studies showed improved biofilm architecture, which was related to the expression of several hypha-specific genes. Based on recent updates, research is still needed to increase our knowledge on the genetic network of adhesion and biofilm formation by , as well as the protein diversity that mediates interactions with inert materials and biological surfaces. Here, we have reviewed the main aspects related to adhesion and biofilm formation in and summarized current knowledge on the significance of these virulence factors in this opportunistic species.
Topics: Candida tropicalis; Gene Regulatory Networks; Biofilms; Quorum Sensing; Phenotype
PubMed: 36809069
DOI: 10.1139/cjm-2022-0195 -
Cellular and Molecular Gastroenterology... 2022We previously showed that abundance of Candida tropicalis is significantly greater in Crohn's disease patients compared with first-degree relatives without Crohn's...
BACKGROUND & AIMS
We previously showed that abundance of Candida tropicalis is significantly greater in Crohn's disease patients compared with first-degree relatives without Crohn's disease. The aim of this study was to determine the effects and mechanisms of action of C tropicalis infection on intestinal inflammation and injury in mice.
METHODS
C57BL/6 mice were inoculated with C tropicalis, and colitis was induced by administration of dextran sodium sulfate in drinking water. Disease severity and intestinal permeability subsequently were evaluated by endoscopy, histology, quantitative reverse-transcription polymerase chain reaction, as well as 16S ribosomal RNA and NanoString analyses (NanoString Technologies, Seattle, WA).
RESULTS
Infected mice showed more severe colitis, with alterations in gut mucosal helper T cells (Th)1 and Th17 cytokine expression, and an increased frequency of mesenteric lymph node-derived group 2 innate lymphoid cells compared with uninfected controls. Gut microbiome composition, including changes in the mucin-degrading bacteria, Akkermansia muciniphila and Ruminococcus gnavus, was altered significantly, as was expression of several genes affecting intestinal epithelial homeostasis in isolated colonoids, after C tropicalis infection compared with uninfected controls. In line with these findings, fecal microbiome transplantation of germ-free recipient mice using infected vs uninfected donors showed altered expression of several tight-junction proteins and increased susceptibility to dextran sodium sulfate-induced colitis.
CONCLUSIONS
C tropicalis induces dysbiosis that involves changes in the presence of mucin-degrading bacteria, leading to altered tight junction protein expression with increased intestinal permeability and followed by induction of robust Th1/Th17 responses, which ultimately lead to an accelerated proinflammatory phenotype in experimental colitic mice.
Topics: Animals; Candida tropicalis; Colitis; Dextran Sulfate; Gastrointestinal Microbiome; Humans; Immunity, Innate; Lymphocytes; Mice; Mice, Inbred C57BL
PubMed: 34890843
DOI: 10.1016/j.jcmgh.2021.11.008 -
Frontiers in Cellular and Infection... 2022is an emergent pathogen with a high rate of mortality associated with its biofilm formation. Biofilm formation has important repercussions on the public health system....
is an emergent pathogen with a high rate of mortality associated with its biofilm formation. Biofilm formation has important repercussions on the public health system. However, little is still known about its biofilm life cycle. The present study analyzed the biofilm life cycle of and during various timepoints (24, 48, 72, and 96 h) through biomass assays, colony-forming unit (CFU) counting, and epifluorescence and scanning electron microscopies. Our results showed a significant difference between and biofilms in each biomass and viability assay. All-time samples in the biomass and viability assays confirmed statistical differences between the species through pairwise Wilcoxon tests ( < 0.05). demonstrated a lower biomass growth but reached nearly the same level of biomass at 96 h, while the CFU counting assays exhibited a superior number of viable cells within the biofilm. Statistical differences were also found between and biofilms from 48- and 72-h microscopies, demonstrating with a higher number of total cells within biofilms and cells with a superior cell area and higher matrix production. Therefore, the present study proved the higher biofilm production of .
Topics: Animals; Biofilms; Candida; Candida albicans; Candida tropicalis; Life Cycle Stages
PubMed: 36061861
DOI: 10.3389/fcimb.2022.953168