Synthesis and dipeptidyl peptidase inhibition of N-(4-substituted-2,4-diaminobutanoyl)piperidines

In this paper, we report the synthesis of diastereomerically pure N-(4-substituted-2,4-diaminobutanoyl)piperidines. These compounds were prepared to investigate the influence of the 4-substitution on the dipeptidyl peptidase II (DPP II) activity and selectivity of the parent N-(2,4-diaminobutanoyl)piperidine. The (4S)-methyl compound showed subnanomolar inhibition, comparable with the parent compound. The (4R)-methyl group or bigger substituents decreased the activity.

Attachment of Candida to mammalian tissues--clinical and experimental studies

In this study we investigated whether a correlation between the frequency of candidal vaginitis and in vitro adherence of Candida albicans to human vaginal epithelial cells exists. The in vitro adherence of C. albicans to epithelial cells collected from 347 women of fertility and postmenopausal age, who did not suffer from vaginitis was assessed microscopically. Epithelial cells from women of the groups with known high frequency of vaginitis: diabetic and pregnant women revealed increased ability of in vitro adherence in comparison with a control group. We also investigated whether a correlation between the hormonal status of the women and adherence capacity of the epithelial cells exists. In vivo attachment of C. albicans to epithelial cells was studied in an experimental murine vaginitis model and assessed histopathologically in tissue sections or microscopically in mounts of exfoliated cells. Attempts were made to block the in vivo attachment and prevent infection by pretreating the animals with substances analogous to the fungal cell walls: substances which were previously found to be inhibitory in the in vitro adherence assay. Chitin, its component - N-acetylglucosamine (NAG) and a soluble extract derived from chitin (CSE) inhibited in vivo attachment and prevented infection.