Hydroxylative activity of Aspergillus niger towards androst-4-ene and androst-5-ene steroids.

abstract：:The inhibition of testosterone 5alpha-reductase activity by 3-oxo-4-androstene-17beta-carboxylic acid in the male reproductive organs of the rat was demonstrated in vitro. The medium for incubation of caput epididymis showed the highest concentration of 5alpha-dihydrotestosterone (5alpha-DHT) whereas the highest conce...

journal_title：Steroids

authors： Saksena SK,Lau IF,Chang MC

更新日期：1976-06-01 00:00:00

abstract：:During the periparturient period, dairy cows are subjected to physiological changes that may induce immunosuppression and an increased susceptibility of the animal to bacterial infections such as mastitis. The incidence of clinical environmental mastitis is high during the last period of gestation, at parturition and ...

journal_title：Steroids

authors： Winters KR,Meyer E,Van Merris VM,Van Den Broeck WL,Duchateau L,Burvenich C

更新日期：2003-05-01 00:00:00

abstract：:The abilities of a variety of estrogens and antiestrogens to stimulate DNA synthesis in the prepuberal rat uterus were compared. One microgram of each compound was administered in vivo via a single intraperitoneal injection. DNA synthesis was assayed in vitro in isolated nuclei 24 h later. The relative mitogenicities ...

journal_title：Steroids

authors： Stack G,Korach K,Gorski J

更新日期：1989-08-01 00:00:00

abstract：:Ethynylestradiol (EE2) is one of the most potent endocrine disrupting compounds capable to induce estrogenic effects even at trace level concentrations in the aquatic environment. Methods for detecting EE2 in such concentrations are generally based on GC or HPLC coupled to at least one mass spectrometer. Another appro...

journal_title：Steroids

authors： Schneider C,Schöler HF,Schneider RJ

更新日期：2004-04-01 00:00:00

abstract：:Immature hypophysectomized rats were injected with PMS; some groups received hCG 48h later. The C17,20-lyase activity in the granulosa cells removed from the large preovulatory follicles was estimated by the amount of labelled acetic acid produced from 21 (14C) progesterone or 17-hydroxyprogesterone. 17 alpha-hydroxyl...

journal_title：Steroids

authors： Johnson DC,Griswold T

更新日期：1983-11-01 00:00:00

abstract：:The first convenient chemical synthesis of 7alpha-hydroxyandrost-4-ene-3,17-dione is reported. Androsta-4,6-diene3, 17-dione was converted into its 6alpha, 7alpha-epoxy-derivative; reduction of the epoxide with aluminum amalgam gave 7alpha-hydroxyandrost-4-ene-3,17-dione. This reducing agent is more efficient than chr...

journal_title：Steroids

authors： Hossain AM,Kirk DN,Mitra G

更新日期：1976-05-01 00:00:00

abstract：:17-Hydroxyprogesterone is a well-known precursor of androstenedione in adrenal biosynthesis. This study using sheep adrenal incubations demonstrates that 11-deoxycortisol, the precursor of cortisol synthesis, also can be a precursor of androstenedione. Indeed, our data show that androstenedione synthesis is negatively...

journal_title：Steroids

authors： Auzéby A,Bogdan A,Touitou Y

更新日期：1991-01-01 00:00:00

abstract：:Most pregnant women have symptoms of gastroesophageal reflux disease (GERD) during pregnancy. Postmenopausal hormone replacement therapy is associated with GERD. The effects of estradiol on lower esophageal sphincter (LES) motility and GERD are not clearly known. The purpose of this study is to investigate the effects...

journal_title：Steroids

authors： Tsai CC,Tey SL,Chang LC,Su YT,Lin KJ,Huang SC

更新日期：2018-08-01 00:00:00

abstract：:The accurate analysis of trace components in complex biological matrices requires the use of reliable internal standards. For liquid chromatography/mass spectrometry analysis, the stable isotope-labeled analogues of the analyte molecules are the most appropriate internal standards. In this paper the synthesis of the 3...

journal_title：Steroids

authors： Mitamura K,Mabuchi T,Nagae K,Nakajima M,Matsumoto R,Fujioka S,Sato K,Satoh née Okihara R,Iida T,Ogawa S,Hofmann AF,Ikegawa S

更新日期：2012-11-01 00:00:00

abstract：:Neutral steroids are difficult to analyse using desorption ionisation methods coupled with mass spectrometry (MS). However, steroids with an unhindered ketone group can readily be derivatised with the Girard P (GP) reagent to give GP hydrazones. Steroid GP hydrazones contain a quaternary nitrogen atom and are readily ...

journal_title：Steroids

authors： Khan MA,Wang Y,Heidelberger S,Alvelius G,Liu S,Sjövall J,Griffiths WJ

更新日期：2006-01-01 00:00:00

abstract：:A procedure utilizing co-chromatography and complementary antiserum comparisons was employed to assess the specificity of a cortisol radioimmunoassay for use in the chronically catheterized fetal sheep preparation. Complementary antiserum comparisons is a technique by which two different cortisol antisera, prepared fr...

journal_title：Steroids

authors： Magyar DM,Buster JE,Elsner CW,Nathanielsz PW,Oliveros R,Abraham GE

更新日期：1979-01-01 00:00:00

abstract：OBJECTIVE:The cut-off value for salivary cortisol measurement for the diagnosis of Cushing's syndrome (CS) may depend both on the severity of the disease and the composition of control group. Therefore, we examined the utility of midnight salivary cortisol measurements in patients who were evaluated for signs and sympt...

journal_title：Steroids

authors： Sereg M,Toke J,Patócs A,Varga I,Igaz P,Szücs N,Horányi J,Pusztai P,Czirják S,Gláz E,Rácz K,Tóth M

更新日期：2011-01-01 00:00:00

abstract：:Inflammatory cytokines interleukin-1 (IL-1) and tumor necrosis factor-α (TNF-α) regulate the activity of the hypothalamo-pituitary-adrenal (HPA) axis at several levels. Although hypothalamic CRH secretion may be the primary mechanism by which these cytokines activate the HPA axis, IL-1 expression is increased within t...

journal_title：Steroids

authors： Tkachenko IV,Jääskeläinen T,Jääskeläinen J,Palvimo JJ,Voutilainen R

更新日期：2011-09-01 00:00:00

abstract：:An efficient procedure for the chemical synthesis of 3 beta-hydroxy-5 alpha-cholest-8-en-7-one and 3 beta-hydroxy-5 alpha-cholest-8-en-11-one is described. These ketosterols have been shown to have possible significant hypocholesterolemic effects when fed to normal rats at a level of 0.15% in a laboratory chow diet. T...

journal_title：Steroids

authors： Parish EJ,Nanduri VB,Seikel JM,Kohl HH,Nusbaum KE

更新日期：1986-11-01 00:00:00

abstract：:Besides regulating water and electrolyte homeostasis, the mineralocorticoid receptor (MR) elicits pathophysiological effects in the renocardiovascular system. Although the MR's closest relative, the glucocorticoid receptor (GR), acts as a transcription factor at the same hormone-response-element (HRE), activated gluco...

journal_title：Steroids

authors： Grossmann C,Ruhs S,Seiferth A,Gekle M

更新日期：2010-08-01 00:00:00

abstract：:Using a whole cell suspension assay technique, we have examined both the specific binding of testosterone (T) and dihydrotestosterone (17 beta-hydroxy-5 alpha-androstan-3-one) (DHT) and the subsequent distribution of androgen binding activity within MCF-7 human breast cancer cells. We have observed that both androgens...

journal_title：Steroids

authors： MacIndoe JH,Woods GR,Lee FJ

更新日期：1981-10-01 00:00:00

abstract：:The syntheses of 15beta-carboxyethylmercapto-5alpha-dihydrotestosterone, 15beta-carbosyethylmercapto-5alpha-androstane-3beta, 17beta-diol and 15beta-carboxyethylmercapto-5alpha-androstane-3alpha, 17beta-diol and the preparation of their bovine serum albumin (BSA) conjugates are described. These conjugates were employe...

journal_title：Steroids

authors： Rao PN,Khan AH,Moore PH Jr

更新日期：1977-02-01 00:00:00

abstract：:The ability of human adult adrenal to utilize progesterone (P4) for cortisol (F) synthesis in vitro has been compared with that of fetal adrenal tissue. Explant cultures were studied for 6 days using Ham's F10 medium supplemented with 10% fetal bovine serum (FBS), with or without added P4 as substrate. Short-term (4h)...

journal_title：Steroids

authors： Branchaud CL,Lipowski L,Dhanani B,Goodyer CG,Lefebvre Y

更新日期：1986-04-01 00:00:00

abstract：:The reaction of 23-oxotigogenin acetate with TMSOTf in THF afforded the corresponding bisnorcholanic lactone in 60% yield. The analogous reactions carried out in dichloromethane or benzene gave the rearranged products--the isomeric spirostanic ketone (10-15%) and bisfuran (40-42%). Similar products were also obtained ...

journal_title：Steroids

authors： Jastrzebska I,Siergiejczyk L,Tomkiel AM,Urbańczyk-Lipkowska Z,Wójcik D,Morzycki JW

更新日期：2009-08-01 00:00:00

abstract：:Nuclear membrane bound testosterone 5 alpha-reductase solubilized in active form from human prostatic tissue by 0.5% n-octyl beta-D-glucopyranoside was purified by a four-step chromatographic procedure including DEAE-Trisacryl ion exchange, hydroxylapatite adsorption, testosterone-Sepharose affinity and Sepharose 4B g...

journal_title：Steroids

authors： Quemener E,Amet Y,di Stefano S,Fournier G,Floch HH,Abalain JH

更新日期：1994-12-01 00:00:00

abstract：:A method for the synthesis and purification of 6beta-iodomethyl-19-norcholest-5(10)-ene-3beta-ol-131I of greater than 98 mole% chemical purity and greater than 99% radiochemical purity is presented. Carbon-13 and proton NMR were used to establish the identity and purity. Discrepancies in the characterization of this c...

journal_title：Steroids

authors： Scott KN,Couch MW,Mareci TH,Williams CM

更新日期：1976-08-01 00:00:00

abstract：:Bile acid conjugates are found in human breast cyst fluid in average concentrations about 50-fold greater than those in blood. Because epidemiologic studies have linked colon and breast cancer and aberrant bile acid profiles are associated with colon cancer risk, we decided to study the influence of bile acid conjugat...

journal_title：Steroids

authors： Raju U,Katz J,Levitz M

更新日期：1997-10-01 00:00:00

abstract：:Many flavonoids and isoflavonoids have anti-diabetic effects in animal models. However, the mechanisms that are involved are generally unclear. Since 11β-hydroxysteroid dehydrogenases (HSD11Bs) play important roles in diabetes, we hypothesize that flavonoids and isoflavonoids may affect diabetes by targeting two isofo...

journal_title：Steroids

authors： Zhu Q,Ge F,Dong Y,Sun W,Wang Z,Shan Y,Chen R,Sun J,Ge RS

更新日期：2018-04-01 00:00:00

abstract：:Agave plants are popular for their myriad applications in traditional medicine attributed to their reported anti-inflammatory, immunomodulatory, cytotoxic and antifungal activities. The aim of this study was to examine the anti-inflammatory, immunomodulatory and ulceroprotective activity of Agave species in relation t...

journal_title：Steroids

authors： El-Hawary SS,El-Kammar HA,Farag MA,Saleh DO,El Dine RS

更新日期：2020-08-01 00:00:00

abstract：:Two new sterols, (24E)-24-n-propylidenecholesterol and 24 epsilon-n-propylcholesterol, were isolated from a cultured marine Chrysophyte. Since most of the steroids found in marine invertebrates are unchanged or modified sterols of algal or symbiotic origin, the discovery of these two unusual sterols in a unicellular a...

journal_title：Steroids

authors： Rohmer M,Kokke WC,Fenical W,Djerassi C

更新日期：1980-02-01 00:00:00

abstract：:Human mammary medullary carcinoma cells (passages 16 to 21) were cultured for 2 days to allow for attachment, followed by 6 days of culture in either fetal calf serum, human cord blood, human amniotic fluid, or growth factors in the presence or absence of purified human alpha-fetoprotein (AFP). When growth factors wer...

journal_title：Steroids

authors： Leal JA,Gangrade BK,Kiser JL,May JV,Keel BA

更新日期：1991-05-01 00:00:00

abstract：:To simultaneously measure some targeted endocrine disruptors and several forms of sex hormones in rat serum, an accurate analytical procedure was developed. First, a comparison between a polymeric-based solid-phase extraction (SPE) and a micro-extraction by packed sorbent was performed to choose the optimal method to ...

journal_title：Steroids

authors： Tournier M,Pouech C,Quignot N,Lafay F,Wiest L,Lemazurier E,Cren-Olivé C,Vulliet E

更新日期：2015-12-01 00:00:00

abstract：:In the present study the possible dual effects of adenosine as substrate and adenosine receptor agonist in rat granulosa cells, cumulus-oocyte complexes, luteal cells and ovarian membranes are discussed. Adenosine is an indispensable compound in cell energy metabolism, as precursor to cofactors, second messenger and n...

journal_title：Steroids

authors： Billig H,Rosberg S,Johanson C,Ahrén K

更新日期：1989-11-01 00:00:00

abstract：:Removal of free calcium ions from the incubation medium of isolated bovine adrenocortical cells with EGTA reduced basal cortisol synthesis and blocked the effects of ACTH; additional calcium restored normal steroid synthesis. Calcium channel blockers, verapamil and nitrendipine and the calmodulin antagonist, trifluope...

journal_title：Steroids

authors： Davies E,Kenyon CJ,Fraser R

更新日期：1985-06-01 00:00:00

abstract：:Radioimmunoassay (RIA) for testosterone (T) in unchromatographed plasma extracts from ATD-treated rats gave spuriously high values for T. Cross-reaction and chromatographic studies subsequently showed that ATD and, to a much greater extent, its metabolite(s) were responsible for this overestimation. Celite column chro...

journal_title：Steroids

authors： Donaldson MD,Forest MG

更新日期：1980-12-01 00:00:00