Experimental rat vaginal infection with Candida parapsilosis

The experimental vaginopathic potential of Candida parapsilosis was determined in ovariectomized rats maintained under pseudoestrus by estrogen administrations. Of the 3 strains of C. parapsilosis tested, that isolated from the vagina of a woman affected by vulvovaginal candidosis gave a prolonged and sustained experimental vaginitis, not different in extent and duration from that caused by a vaginal isolate of C. albicans from a vaginitis patient. The other two isolates of C. parapsilosis (one from the vagina of an asymptomatic subject and another from soil) were unable to infect rat vagina. Microscopic observations of PAS-stained vaginal smears from rats infected with the vaginopathic isolate of C. parapsilosis showed pronounced adherence of yeasts to exfoliated cells. In addition, this isolate of C. parapsilosis produced an elevated quantity of acid proteinase in vitro.     

Cultivation ofCandida blankii in simulated bagasse hemicellulose hydrolysate

Summary All fourCandida blankii isolates evaluated for growth in simulated bagasse hemicellulose hydrolysate utilized the sugars and acetic acid completely. The utilization ofd-xylose,l-arabinose and acetic acid were delayed by the presence ofd-glucose, but after glucose depletion the other carbon sources were utilized simultaneously. The maximum specific growth rate of 0.36 h^–1 and cell yield of 0.47 g cells/g carbon source assimilate compared with published results obtained withC. utilis. C. blankii appeared superior toC. utilis for biomass production from hemicellulose hydrolysate in that it utilizedl-arabinose and was capable of growth at higher temperatures.     

Ultrastructural localization of ‘anixiopsin’: a lectin of the fungus Anixiopsis stercoraria (Hansen) Hansen

In order to localize the anixiopsin, a lectin of the keratinolytic fungus Anixiopsis stercoraria, the authors used a monospecific antiserum prepared by immunization of rabbits with their own erythrocytes coated in vitro with anixiopsin. In light and scanning electron microscopies, lectinic sites were visualized by means of latex microspheres sensitized with anti-rabbit IgG antibodies. In transmission electron microscopy using the IgG fraction of the rabbit anti-anixiopsin immune sera and protein A-gold, anixiopsin seemed mainly present on the outermost cell wall layer of the ascospores, in a pseudomembraneous structure dense to electrons. Implications of these results on physical and biological properties of the lectin are discussed.     

High rate of Candida deep-seated infection in patients under chronic hemodialysis with extended central venous catheter use

BackgroundHemodialysis has been described as an important risk factor for the development of candidemia in patients suffering from chronic renal failure.AimsThe aim of this study was to evaluate the epidemiology of candidemia in outpatients with renal replacement therapy (RRT) by hemodialysis where the fungemia clearly represents a healthcare-associated infection.MethodsWe retrospectively collected clinical and laboratory data from patients undergoing at least 3 months of RRT by hemodialysis who developed candidemia within 48 h of hospital admission.ResultsWe identified 14 patients with candidemia with central venous catheters (CVC) in place for 11–277 days before developing fungemia. Deep-seated infection was documented in 6 out of 14 candidiasis cases (43%), including 5 cases of endocarditis (36%).ConclusionsCVC in patients under RRT should be promptly replaced by fistulas and grafts to avoid bloodstream infections. Facing a case of candidemia, adequate source control and prompt initiation of antifungal therapy are mandatory to avoid morbidity and mortality.     

Th17 Inflammation Model of Oropharyngeal Candidiasis in Immunodeficient Mice

Oropharyngeal Candidiasis (OPC) disease is caused not only due to the lack of host immune resistance, but also the absence of appropriate regulation of infection-induced immunopathology. Although Th17 cells are implicated in antifungal defense, their role in immunopathology is unclear. This study presents a method for establishing oral Th17 immunopathology associated with oral candidal infection in immunodeficient mice. The method is based on reconstituting lymphopenic mice with in vitro cultured Th17 cells, followed by oral infection with Candida albicans (C. albicans). Results show that unrestrained Th17 cells result in inflammation and pathology, and is associated with several measurable read-outs including weight loss, pro-inflammatory cytokine production, tongue histopathology and mortality, showing that this model may be valuable in studying OPC immunopathology. Adoptive transfer of regulatory cells (T_regs) controls and reduces the inflammatory response, showing that this model can be used to test new strategies to counteract oral inflammation. This model may also be applicable in studying oral Th17 immunopathology in general in the context of other oral diseases.     

Primary allenic alcohols of high optical purity via lipase catalyzed resolution

The lipase from Candida rugosa lipase (CRL) was used for the preparation of optically active primary allenic alcohols with axial chirality. The biocatalytic material used was the commercial CRL (C-CRL) and propan-2-ol-treated CRL (PT-CRL). The kinetic resolution of (±)-1 and (±)-3a–c in water using C-CRL resulted in either the absence of or low enantiomeric ratio, whereas PT-CRL increased the E-value. Under optimized conditions (temperature and medium used) (+)-S-3a and (−)-R-4 were isolated in excellent yields and high optical purity (o.p.). The resolution was carried out on multigram scale in water/n-hexane at 4 °C.     

Glutathione levels during thermal induction of the yeast-to-mycelial transition in Candida albicans

Glutathione (GSH) levels were directly monitored by reverse phase HPLC during the thermal yeast-to-mycelial induction of Candida albicans. The GSH levels decreased approximately 100-fold within 120 min which corresponded to the time of maximal yeast-to-mold conversion. The yeast to mold conversion was inhibited by 1-p-chlorophenyl-4,4-dimethyl-5-diethylamino-1-penten-3-one (CDDP), a thiol-specific alkylator, which prevented the decline in GSH levels. These results are discussed with respect to the potential involvement of intracellular GSH levels in regulation of the yeast-to-mold dimorphism in Candida albicans.     

Purification and characterization of two isoforms from Candida rugosa lipase B

Two isoforms of Candida rugosalipase B (LB1 and LB2) were purified by anionic exchange chromatography. The lipases had the same N-terminal sequence, carbohydrate content and pH and thermal stability but different pIs and significant differences in their activities against different p-nitrophenol esters and triacylglycerides.