Indoximod opposes the immunosuppressive effects mediated by IDO and TDO via modulation of AhR function and activation of mTORC1.

Indoximod has shaped our understanding of the biology of IDO1 in the control of immune responses, though its mechanism of action has been poorly understood. Previous studies demonstrated that indoximod creates a tryptophan (Trp) sufficiency signal that reactivates mTOR in the context of low Trp concentrations, thus opposing the effects caused by IDO1. Here we extend the understanding of indoximod's mechanism of action by showing that it has pleiotropic effects on immune regulation.

Enterococcus in surface waters from the Des Moines River (Iowa) watershed: location, persistence and vancomycin resistance.

The object of this study was to quantify vancomycin-resistant enterococci in surface water from Central Iowa obtained from April 2007 to August 2007. Water from established sampling sites in four watersheds was plated on bile-esculin agar. Presumptively identified enterococci were categorized as "above the level of concern" if the sample contained ≥ 107 CFU per 100 ml.

Quantitative real time PCR detection of Clostridium difficile growth inhibition by probiotic organisms.

Background: Probiotic microorganisms are potential treatments for Clostridium difficile diarrheal disease (CDD) but better methods are needed to determine the relative potency of probiotic microorganisms against pathogenic organisms in mixed cultures.

Aim: Quantify C. difficile in the presence of putative probiotic organisms using molecular methods to determine relative probiotic potency.

Sodium choleate (NaCho) effects on Candida albicans: implications for its role as a gastrointestinal tract inhabitant.

Candida albicans at times resides in the intestinal tract, where it experiences exposure to bile salts suggesting a study of the effects of crude bile salts in the form of sodium choleate (NaCho) on C. albicans growth, expression of virulent phenotypes, and adaptation to physiological challenges in vitro. Growth and phenotype alteration was examined by challenging clinical isolates of C.

Antifungal mechanisms supporting boric acid therapy of Candida vaginitis.

Background: Boric acid is a commonly cited treatment for recurrent and resistant yeast vaginitis, but data about the extent and mechanism of its antifungal activity are lacking.

Objectives: The aim of this study was to use in vitro methods to understand the spectrum and mechanism of boric acid as a potential treatment for vaginal infection.

Methods: Yeast and bacterial isolates were tested by agar dilution to determine the intrinsic antimicrobial activity of boric acid.

Tetracycline effects on Candida albicans virulence factors.

Object: To determine if tetracycline, previously reported to increase the probability of developing symptomatic vaginal yeast infections, has a direct effect on Candida albicans growth or induction of virulent phenotypes.

Method: In vitro, clinical isolates of yeast were cultivated with sublethal concentrations of tetracycline and yeast cell counts, hyphal formation, drug efflux pump activity, biofilm production, and hemolysin production were determined by previously reported methods.

Results: Tetracycline concentrations above 150 microg/mL inhibited Candida albicans, but at submicrogram/mL, a modest growth increase during the early hours of the growth curve was observed.

Effect of commonly used herbicides on the virulence factor CDR1 in Candida albicans.

The ubiquitous yeast Candida albicans becomes a troublesome pathogen by inducing virulence factors in response to environmental stimuli. Among these virulence factors is a drug-exporting transport protein, Cdrlp, which renders cells resistant to certain antifungal drugs. The expression of the CDR1 gene responds to a wide spectrum of stimuli, including drugs, heat shock, and steroid hormones.

Adherence and blocking of Candida albicans to cultured vaginal epithelial cells: treatments to decrease adherence.

Background: Pathogenesis of mucosal microorganisms depends on adherence to the tissues they colonize and infect. For Candida albicans, cell surface hydrophobicity may play a significant role in tissue binding ability.

Methods: A continuous cell line of vaginal epithelial cells (VEC) was grown in keratinocyte serum-free medium (KSFM) with supplements and harvested by trypsinization.

Key physiological differences in Candida albicans CDR1 induction by steroid hormones and antifungal drugs.

The Candida albicans CDR1 gene, encoding an ABC transporter that functions as an efflux pump, is thought to be involved in pathogenic adaptation and uses mammalian hormones and other environmental cues to regulate its activity. Exposure of several clinical isolates of C. albicans to 1 x 10(-8) M 17beta-oestradiol increased CDR1 expression and the isolates showed a positive correlation between oestrogen induction of CDR1 and growth in the presence of oestrogen.

Surface modifying substances that reduce apparent yeast cell hydrophobicity.

Objective: To determine whether several topical compounds and other chemical entities are able to diminish the surface hydrophobicity of yeast cells.

Method: Hydrophobicity of yeast cells was determined by binding styrene microspheres to the surface of untreated yeast or yeast pre-incubated with various substances with potential for cell surface modification. The degree of microsphere adherence to yeast cells was measured by flow cytometry.

Flow cytometry of Candida albicans for investigations of surface marker expression and phagocytosis.

Several cytoplasmic virulence factors of Candida albicans are altered in the presence of estrogen and this fact may imply the existence of a global virulence regulatory system in this organism. The response of virulence-associated surface markers to estrogen, however, has not been studied. We exploited flow cytometry methods for assessment of the iC3b receptor analog and mannoproteins on 2 clinical yeast strains selected for their different rates of growth in the presence of estradiol 17beta.

Evaluation of relative yeast cell surface hydrophobicity measured by flow cytometry.

Objective: To develop an efficient method for evaluating cell surface hydrophobicity and to apply the method to demonstrate the effects of fungal growth conditions on cell surface properties.

Methods: Yeast isolates were suspended in phosphate-buffered saline and mixed with deep blue-dyed polystyrene microspheres. Flow cytometry was used to detect the degree of microsphere binding to yeast cells.

Isolation and partial characterization of Hsp90 from Candida albicans.

Hsp90 is a stress-induced protein involved in many cellular processes including the regulation of signal transduction and steroid hormone response pathways in higher eukaryotic cells. Candida albicans hsp90 has a mass of 82 -Da and has previously been implicated as a virulence factor. A 47-kDa C-terminal fragment of Candida hsp90 is a target for an immune response to C.