Facile synthesis of carbon-11-labeled cholesterol-based cationic lipids as new potential PET probes for imaging of gene delivery in cancer.

abstract：:Previous studies have demonstrated a persistent rise in serum cortisol concentrations after cardiac surgery. To further investigate this finding and to evaluate the effect of hemodilution that occurs with the onset of cardiopulmonary bypass (CPB), concentrations of cortisol-binding globulin (CBG), total and unbound co...

journal_title：Steroids

authors： Roth-Isigkeit AK,Dibbelt L,Schmucker P

更新日期：2000-09-01 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：:Testosterone (17 beta -hydroxy-4-androsten-3-one ; T) and dihydrotestosterone (17 beta -hydroxy-5 alpha -androstan-3-one ; DHT) concentrations were determined by radioimmunoassay in different fetal tissues taken from male guinea-pigs. Androgen concentrations were maximal in the components of the Wolffian duct (vas def...

journal_title：Steroids

authors： Rigaudière N

更新日期：1981-08-01 00:00:00

abstract：BACKGROUND:Estrogen replacement therapy increases risk for ovarian epithelial cancer, a cancer of mainly older women, yet the response of older ovarian surface epithelium (OSE) to repeat estrogen exposure overtime has not been studied. We have previously reported significant reductions in estrogen receptor (ER) protein...

journal_title：Steroids

authors： Gulliver LS,Hurst PR

更新日期：2012-05-01 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：:The therapeutic use of progesterone following traumatic brain injury has recently entered phase III clinical trials as a means of neuroprotection. Although it has been hypothesized that progesterone protects against calcium overload following excitotoxic shock, the exact mechanisms underlying the beneficial effects of...

journal_title：Steroids

authors： Luoma JI,Kelley BG,Mermelstein PG

更新日期：2011-08-01 00:00:00

abstract：:Phytochemical analysis of the fruits of Raphia vinifera led to the isolation of four new steroidal saponins (1-4), along with six known secondary metabolites (6-10). The structures of the isolated compounds were determined based on the analyses of NMR and mass spectrometric data, and chemical degradation reactions. Am...

journal_title：Steroids

authors： Chi GF,Sop RVT,Mbaveng AT,Omollo Ombito J,Fotso GW,Nguenang GS,Kuete V,Efferth T,Ngadjui BT

更新日期：2020-11-01 00:00:00

abstract：:The hydrolysis of 108 esters of norethisterone (17 alpha-ethynyl-17 beta-hydroxyestr-4-en-3-one) was studied in vitro using a rabbit liver preparation. Introduction of a double or triple bond into a straight-chain ester did not inhibit hydrolysis but a marked reduction in hydrolysis was produced on replacement of a me...

journal_title：Steroids

authors： Naderi S,Fotherby K

更新日期：1983-03-01 00:00:00

abstract：:There are currently two main candidates for the membrane receptor for 1,25(OH)2D3: the 1,25D3-MARRS protein/ERp57; and the classical VDR. The 1,25D3-MARRS protein is essential for hormone-stimulated phosphate and calcium uptake in chick intestinal cells, whereas the VDR is not. The 1,25D3-MARRS protein also shows a hi...

journal_title：Steroids

authors： Nemere I

更新日期：2005-05-01 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：:A convenient procedure for the synthesis of 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol via a modified homologation sequence of the intermediate 3 alpha,7 alpha,12 alpha-triformyloxy-24-oxo-25-diazo-25-homo-5 beta-cholane involving a homogeneous medium is described. This involves treating the intermediate alp...

journal_title：Steroids

authors： Dayal B,Bagan E,Speck J,Salen G

更新日期：1980-04-01 00:00:00

abstract：:Steroid delta 4-5 alpha- and delta 4-5 beta-reductase activity was determined in 16 human mammary tumors and 8 DMBA-induced rat mammary tumors using a spectrophotometric assay. Steroid delta 4-5 alpha-reductase was present in all tumors investigated while delta 4-5 beta-reductase was detected in only 6 estrogen recept...

journal_title：Steroids

authors： Abul-Hajj YJ

更新日期：1979-01-01 00:00:00

abstract：:Extranuclear estrogen receptors may mediate rapid effects of estradiol that communicate with nuclear receptors and contribute to proliferation of human cancers bearing these signaling proteins. To assess these growth-promoting pathways, we undertook controlled homogenization and fractionation of NIH-H23 non-small cell...

journal_title：Steroids

authors： Pietras RJ,Márquez DC,Chen HW,Tsai E,Weinberg O,Fishbein M

更新日期：2005-05-01 00:00:00

abstract：:A series of amphiphilic derivatives of (3β,17β)-3-hydroxyandrost-5-ene-17-carboxylic acid (1) with the polyamine spermine and three other diamines, 1,2-diaminoethane, piperazine and cadaverine, were synthesized and their antimicrobial activity and cytotoxicity were investigated. Among the target compounds, several one...

journal_title：Steroids

authors： Özdemir Z,Bildziukevich U,Šaman D,Havlíček L,Rárová L,Navrátilová L,Wimmer Z

更新日期：2017-12-01 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：:Optimal assay conditions for cholesterol 7 alpha-hydroxylase activity in swine liver microsomes were determined. The enzyme activity is induced three-fold by feeding cholestyramine to the swine. This suggests that cholesterol 7 alpha-hydroxylase is likely to be the rate-limiting enzyme for biosynthesis of bile acids i...

journal_title：Steroids

authors： Li JR,Kim DN

更新日期：1979-03-01 00:00:00

abstract：:A sensitive accurate assay for the placental microsomal 3 beta-hydroxysteroid dehydrogenase (E.C.1.1.1.51) has been developed using tritiated substrates. Kinetic analysis of the enzyme with 3 beta-hydroxy-5-androsten-17-one and 3 beta-hydroxy-5-pregnen-20-one indicates that the apparent Km values for these substrates ...

journal_title：Steroids

authors： Gibb W

更新日期：1979-04-01 00:00:00

abstract：:It has been previously demonstrated that 1,25 dihydroxyvitamin D(3) (1,25-D(3)) exerts inhibitory effects in breast cancer cells. The aim of this study was to determine whether mitogen-activated protein kinase (MAPK) pathways are associated with 1,25-D(3)-induced cell death in breast cancer. We used three breast cell ...

journal_title：Steroids

authors： Brosseau CM,Pirianov G,Colston KW

更新日期：2010-12-12 00:00:00

abstract：:Structural modifications of natural products with complex structures like steroids require great synthetic effort. A review of literature is presented on the chemistry of the steroidal hormone 17α-methyltestosterone that is approved by Food and Drug Administration (FDA) in the United States as an androgen for estrogen...

journal_title：Steroids

authors： El-Desoky el-SI,Reyad M,Afsah EM,Dawidar AA

更新日期：2016-01-01 00:00:00

abstract：:Enzyme immunoassays (EIA) are commonly utilized for the evaluation of androgens in biological fluids; however, careful consideration must be given to cross-reactivity with other endogenous sex-steroid hormones. Our purpose was to determine the validity of a commonly-utilized commercially-available dihydrotestosterone ...

journal_title：Steroids

authors： Yarrow JF,Beck DT,Conover CF,Beggs LA,Goldberger BA,Borst SE

更新日期：2013-12-11 00:00:00

abstract：:This article describes the oxidation of cholesta-5,7-dien-3beta-yl acetate (4) with the urea-hydrogen peroxide adduct (UHP) using methyltrioxorhenium (MTO) as catalyst, under various conditions. Specifically, the effects of using different solvents (CHCl(3) and ethers) and additives (EtOH and pyridine) on the course o...

journal_title：Steroids

authors： Musumeci D,Sica D

更新日期：2002-06-01 00:00:00

abstract：:The effect of cortisol and prostaglandin inhibitors on the growth and development of germinating mung bean, Vigna radiata L. Wilzek, cv. Jumbo was investigated. Cortisol, indomethacin, and a mixture of cortisol with aspirin, or benoxaprofen significantly increased radicle length and the number of lateral roots as comp...

journal_title：Steroids

authors： Gawienowski AM,Csernus KM,Simon JE,Craker LE

更新日期：1985-08-01 00:00:00

abstract：:Two-hydroxyestrone (2OHE-1) and 16alpha-hydroxyestrone (16OHE-1) are two estrogen metabolites that may play important roles in the development or promotion of breast cancer. Our study assessed the reliability of a newly developed kit procedure for measuring 2OHE-1. Although under certain conditions the assay would not...

journal_title：Steroids

authors： Spierto FW,Gardner F,Smith SJ

更新日期：2001-01-01 00:00:00

abstract：:20-Hydroxyecdysterone - (2β,3β,5β,22R)-2,3,14,20,22,25-hexahydroxycholest-7-en-6-one was isolated in satisfactory yield using ethanol extraction from the aerial part of Silene wolgensis (Hornem.) Otth; sometimes Silene wolgensis (Willd.) Bess. ex Spreng. The complexation of the phytoecdysteroid with β-cyclodextrin was...

journal_title：Steroids

authors： Temirgaziyev BS,Kučáková K,Baizhigit YA,Jurášek M,Džubák P,Hajdúch M,Dolenský B,Drašar PB,Tuleuov BI,Adekenov SM

更新日期：2019-07-01 00:00:00

abstract：:Preimplantation rabbit embryos were incubated with pregnenolone and dehydroisoandrosterone under conditions which gave formazan precipitation by the histochemical technique. The metabolic fate of the labeled steroids was assessed simultaneously. There was no concomitant transformation of pregnenolone to progesterone a...

journal_title：Steroids

authors： Bleau G

更新日期：1981-02-01 00:00:00

abstract：:Complete analysis of the proton nuclear magnetic resonance spectrum of desoxycorticosterone (DOC) has been made using selective double irradiation, two-dimensional experiments, relaxation rate, and nuclear Overhauser effect measurements in order to specify the structure and conformation of products encountered during ...

journal_title：Steroids

authors： Kouadio L,Bernard P,Sabot JF,Petit-Ramel MM,Barbier CM,Pinatel HJ

更新日期：1988-03-01 00:00:00

abstract：:This paper describes three simple and short methods for the conversion of cholic acid into cholylaldehyde with protected hydroxyl groups. The first method involves lithium aluminum hydride reduction of the tetrahydropyranyl ether of methyl cholate and oxidation of the resulting primary alcohol with pyridinium chloroch...

journal_title：Steroids

authors： Batta AK,Tint GS,Dayal B,Shefer S,Salen G

更新日期：1982-06-01 00:00:00

abstract：:Bioconversion of the aromatase inhibitor formestane (4-hydroxyandrost-4-ene-3,17-dione) (1) by the fungus Rhizopus oryzae ATCC 11145 resulted in a new minor metabolite 3,5α-dihydroxyandrost-2-ene-4,17-dione (2) and the known 4β,5α-dihydroxyandrostane-4,17-dione (3) as the major product. The structural elucidation and ...

journal_title：Steroids

authors： Martin GD,Narvaez J,Bulmer R,Durrant MC

更新日期：2016-09-01 00:00:00

abstract：:The mechanistic aspects of the alkali-catalyzed rearrangement of 16alpha-hydroxy-17-keto steroid 1 to 17beta-hydroxy-16-keto steroid 2 are elucidated by use of (18)O- and deuterium-labeling experiments. The (18)O-labeling experiments refute the gem-hydration-quasi-diaxial dehydration mechanism for the rearrangement pr...

journal_title：Steroids

authors： Numazawa M,Nagaoka M,Matsuzaki H,Yamashita K,Komatsu S,Osawa Y

更新日期：2008-09-01 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