Search results for "Candida albicans."
showing 10 items of 309 documents
Diagnosis of systemic candidiasis by enzyme immunoassay detection of specific antibodies to mycelial phase cell wall and cytoplasmic candidal antigens
1993
Diagnosis of systemic Candida infections was attempted by the use of an enzyme-linked immunosorbent assay (EIA) to detect IgG antibodies towards cell wall-bound and cytoplasmic candidal antigens. Cell wall antigens were sequentially solubilized by treatment of germinated blastoconidia of Candida albicans (ATCC 26555 strain) with beta-mercaptoethanol (beta ME extract) and digestion with Zymolyase 20T, a beta-glucanase preparation (Zymolyase extract). Protoplasts obtained after treatment with Zymolyase were osmotically lysed (cytoplasmic antigens). Sera were obtained from patients with systemic (n = 28) and superficial (n = 46) candidiasis. Control sera were obtained from normal healthy indiv…
Candida albicans UBI3 and UBI4 promoter regions confer differential regulation of invertase production to Saccharomyces cerevisiae cells in response …
2002
Candida albicans ubiquitin genes UBI3 and UBI4 encode a ubiquitin-hybrid protein involved in ribosome biogenesis and polyubiquitin, respectively. In this work we show that UBI3 and UBI4 promoter regions confer differentialexpr ession consistent with the function of their encoded gene products. Hybrid genes were constructed containing the SUC2 coding region under the controlof UBI3 or UBI4 promoters in the yeast vector pLC7. Invertase production in Saccharomyces cerevisiae transformants was differentially regulated: the UBI4 promoter was induced by stress conditions (thermalupshift and/or starvation) whereas the UBI3 promoter conferred constitutive invertase production in growing yeast cells…
Flow cytometric assay for estimating fungicidal activity of Amphotericin B in human serum
1992
We describe a simple and rapid bioassay for estimating fungicidal activity of Amphotericin B in human serum using flow cytometry. The method exploits the fact that Candida albicans damaged by Amphotericin B show a decrease in size and take up propidium iodide to exhibit a red fluorescence after deoxycholate treatment. These phenomena display characteristic dose dependencies, and their assessment permits serum fungicidal activity to be broadly grouped into three categories: (1) subfungicidal; (2) fungicidal; and (3) strongly fungicidal. In normal human serum, these three categories correspond to Amphotericin B concentrations of 0 less than or equal to 0.5 micrograms/ml, 0.75-1.5 micrograms/m…
Identification of Candida dubliniensis among oral yeast isolates from an Italian population of human immunodeficiency virus-infected (HIV+) subjects
2002
Candida dubliniensis, an emerging oral pathogen, phenotypically resembles Candida albicans so closely that it is easily misidentified as such. The aim of the present study was to evaluate the usefulness of two phenotypic methods, growth at 45 degrees C and 2,3,5-triphenyltetrazolium chloride (TTC) reduction, for confirming presumptive identification of C. dubliniensis and C. albicans by colony color on CHROMagar Candida (CAC) medium. A combination of these methods was used to establish the prevalence of oral C. dubliniensis in an Italian population of 45 human immunodeficiency virus (HIV)-infected subjects. Twenty-two samples (48.9%) were positive for yeasts on CAC medium producing a total …
A Novel Peptide with Antifungal Activity from Red Swamp Crayfish Procambarus clarkii
2022
The defense system of freshwater crayfish Procambarus clarkii as a diversified source of bioactive molecules with antimicrobial properties was studied. Antimicrobial activity of two polypeptide-enriched extracts obtained from hemocytes and hemolymph of P. clarkii were assessed against Gram positive (Staphylococcus aureus, Enterococcus faecalis) and Gram negative (Pseudomonas aeruginosa, Escherichia coli) bacteria and toward the yeast Candida albicans. The two peptide fractions showed interesting MIC values (ranging from 11 to 700 μg/mL) against all tested pathogens. Polypeptide-enriched extracts were further investigated using a high-resolution mass spectrometry and database search and 14 n…
Comparative genomics of yeast species: new insights into their biology
2003
The genomes of two hemiascomycetous yeasts (Saccharomyces cerevisiae and Candida albicans) and one archiascomycete (Schizosaccharomyces pombe) have been completely sequenced and the genes have been annotated. In addition, the genomes of 13 more Hemiascomycetes have been partially sequenced. The amount of data thus obtained provides information on the evolutionary relationships between yeast species. In addition, the differential genetic characteristics of the microorganisms explain a number of distinctive biological traits. Gene order conservation is observed between phylogenetically close species and is lost in distantly related species, probably due to rearrangements of short regions of D…
Efficacy of a genetically engineered Candida albicans tet-NRG1 strain as an experimental live attenuated vaccine against hematogenously disseminated …
2009
ABSTRACT We report on the efficacy of the genetically engineered Candida albicans tet-NRG1 strain as an experimental live, attenuated vaccine against disseminated candidiasis in both immunocompetent and immunodeficient mice mostly dependent on T-cell immunity. This experimental vaccination model may represent an important tool to unravel the mechanisms of protective immunity during candidiasis.
Characterization of the Differential Pathogenicity of Candida auris in a Galleria mellonella Infection Model
2021
ABSTRACT Candida auris is an emergent multidrug-resistant fungal pathogen considered a severe global threat due to its capacity to cause nosocomial outbreaks and deep-seated infections with high transmissibility and mortality. However, evidence on its pathogenicity and the complex host-pathogen interactions is still limited. This study used the in vivo invertebrate model in Galleria mellonella to assess its virulence, exploring the mortality kinetics, melanization response, and morphological changes after fungal infection compared to Candida albicans and Candida parapsilosis, with known high and low pathogenicity, respectively. All C. auris isolates presented less virulence than C. albicans…
Comparison of disc diffusion assay with the CLSI reference method (M27-A2) for testing in vitro posaconazole activity against common and uncommon yea…
2007
Objectives To evaluate the suitability of disc diffusion (DD) assay for testing posaconazole activity and to corroborate its activity against recently isolated yeasts by the CLSI reference microdilution M27-A2 method. Methods A total of 224 yeast isolates (7 species with 52 to 11 isolates each, and 15 species with 1 to 6 isolates) were evaluated, 125 were recent bloodstream isolates, 30 isolates from other sources and six ATCC isolates that included amphotericin B-resistant Candida albicans ATCC 200955, Candida lusitaniae (ATCC 200950, 200951, 200952 and 200953) and amphotericin B- and itraconazole-resistant Candida tropicalis ATCC 200956. MICs were determined at 24 and 48 h by following th…
LAAE-14, a new anti-inflammatory drug, increases the survival ofCandida albicans-inoculated mice
2003
LAAE-14, a lipidic acid-amido ether derivative, has been recently described as a new anti-inflammatory drug. We have studied the effect of treatment with this compound on the susceptibility of mice to in vivo experimental Candida albicans infection. ICR mice orally treated with LAAE-14 (25 mg kg(-1)) and experimentally intravenously infected showed a significantly increased survival as compared to control mice. In vitro, the compound did not inhibit the growth of C. albicans yeast cells or the yeast-to-hyphal transition. The in vitro production of prostaglandin E2 by peritoneal macrophages in response to the yeasts and hyphae of C. albicans was significantly decreased upon treatment with LA…