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Five new C 21 steroidal glycosides (1–5) were isolated from the stems of Marsdenia tenacissima. The chemical structures and relative configurations of the new compounds were elucidated by mass spectrometry and NMR spectroscopy. Cellular assay of these compounds showed that they are weak cytotoxic to various cell lines.
The aim of this study was to investigate the effect of various bile acids on hepatic type I 11β-hydroxysteroid dehydrogenase (11β-HSD1) activity in vitro. The rat liver microsome fraction was prepared and 11β-HSD1 activity was assayed using cortisol and corticosterone as substrates for the enzyme reaction. The substrate and various concentrations of bile acids were added to the assay mixture. After...
Accurate measurement of testosterone concentration is of critical importance when diagnosing and treating male hypogonadism, congenital adrenal hyperplasia, premature or delayed puberty, and androgen excess in polycystic ovary syndrome or other virilizing conditions. However, some assays have inherent limitations and biases that affect measurement of low-testosterone values. Therefore, we developed...
Treatment of ecdysteroids with excess of TBAF in THF was shown to proceed with stereoselective oxidation at the 9α position of the carbon skeleton. The stereochemistry of the products was confirmed by X-ray analysis. Using this method, 9α-hydroxyecdysteroids were obtained in good yield. The results open a route to novel type of natural and modified steroids that are difficult to access otherwise.
Benign prostatic hyperplasia (BPH) is the noncancerous proliferation of the prostate gland associated with benign prostatic obstruction and lower urinary tract symptoms (LUTS) such as frequency, hesitancy, urgency, etc. Its prevalence increases with age affecting around 70% by the age of 70 years. High activity of 5α-reductase enzyme in humans results in excessive dihydrotestosterone levels in peripheral...
The detection of misuse with naturally occuring steroids is a great challenge for doping control laboratories. Intake of natural anabolic steroids alters the steroid profile. Thus, screening for exogenous use of these steroids can be established by monitoring a range of endogenous steroids, which constitute the steroid profile, and evaluate their concentrations and ratios against reference ranges...
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