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1.
The excretion of ethynyl steroids in milk from a lactating woman taking a daily dose of an oral contraceptive (Conlumin) containing 1 mg of norethindrone and 50 micrograms of mestranol has been studied. Milk was diluted with aq. triethylamine sulphate and steroids were extracted on a Sep-Pak C18 cartridge at 60-64 degrees C. Groups of unconjugated steroids, glucuronides, mono- and disulphates were separated on triethylaminohydroxypropyl Sephadex LH-20. Following hydrolysis and further purification, steroids possessing an ethynyl-substituent were isolated by chromatography on sulphohydroxypropyl Sephadex LH-20 in silver form. Gas chromatographic-mass spectrometric analysis of the O-methyloxime-trimethylsilyl ether derivatives of these steroids, showed the presence of norethindrone and mestranol in the free fraction and of tetrahydro metabolites of norethindrone with 3 alpha,5 alpha, 3 alpha,5 beta and 3 beta,5 alpha configurations in the mono- and disulphate fractions. The disulphate of the 3 alpha,5 alpha isomer was the most abundant ethynyl steroid in milk after 13 days of administration. The site of conjugation of the monosulphates was established by acetylation prior to solvolysis and analysis by gas chromatography-mass spectrometry. This showed that the 3 alpha,5 alpha isomer was conjugated mainly in the 17 beta-position while the 3 alpha,5 beta isomer was conjugated at C-3.  相似文献   

2.
Conjugated ethynyl and endogenous steroids in plasma and urine from two women taking an oral contraceptive (Conlumin) containing 1 mg norethindrone and 50 micrograms mestranol have been analyzed by methods based on anion and ligand exchange chromatography and gas chromatography-mass spectrometry. Conjugated norethindrone and its reduced metabolites with 3 alpha,5 alpha, 3 alpha,5 beta, 3 beta,5 beta and 3 beta,5 alpha configurations were identified in the fluids. The quantitatively major metabolites in plasma were a disulphate of the 3 alpha,5 alpha isomer and a monosulphate of the 3 alpha,5 beta isomer. The renal clearance of the former compound was low. The major urinary metabolite of norethindrone was the 3 alpha,5 beta isomer conjugated with glucuronic or sulphuric acid. Disulphates constituted only a small portion of urinary ethynyl steroids. Metabolic profiles of endogenous neutral steroids in plasma and urine during the contraceptive cycle were compared with profiles during a physiological menstrual cycle. The concentrations of steroids in plasma during contraception were similar to those during the follicular and mid phases of the menstrual cycle, whereas levels of progesterone metabolites were higher in the luteal phase. The urinary excretion of steroids was 15-30% lower during the contraceptive cycle, due to a decrease in excretion of C21O5 steroids, 11-oxygenated androgens and etiocholanolone. The increase of urinary progesterone metabolites seen during the luteal phase was not observed during contraception, but the excretion of 5 beta-pregnane-3 alpha,20 alpha-diol glucuronide was higher than during the follicular and mid phases of the menstrual cycle.  相似文献   

3.
A method for the combined extraction and purification of steroids from testicular tissue is described. The tissue is homogenized and extracted with n-hexane/isopropyl alcohol, and the column to which a Sep-Pak C18 cartridge is attached. Following a wash of the Lipidex/Sep-Pak beds with water to remove inorganic and polar organic substances, steroids are eluted with 85% aqueous methanol. Most of the nonpolar lipids and phospholipids remain on the Lipidex/Sep-Pak. The steroid fraction is acidified with acetic acid, diluted to 70% methanol, and passed through a small bed of Lipidex 5000 to remove cholesterol. Recoveries of testosterone and progesterone are about 90%.  相似文献   

4.
Treatment of well-nourished female rats with a combination of 5 micrograms ethynyl estradiol and 100 micrograms ethynodiol diacetate, increased the DNA content, 3H thymidine incorporation into DNA and mitotic activity in the non-regenerating liver, but impaired liver regeneration after partial hepatectomy. In rats which were moderately malnourished by feeding 25 percent less calories and 50 percent of recommended allowance for vitamins A and B2, OC treatment had similar stimulatory effect on non-regenerating liver, but did not impair liver regeneration after partial hepatectomy. Analysis of nucleotide bases after hydrolysis of unpolymerized nucleotides and nucleosides revealed significant perturbations due to OC treatment. However, the impaired liver regeneration due to OC treatment of well-nourished rats could not be attributed to diminished availability of bases, particularly thymidine. Data on mitotic index and binucleate cell numbers suggest that besides inhibiting mitosis (DNA duplication), OC treatment of well-nourished rats may also impair partitioning of binucleate cells.  相似文献   

5.
Metabolites of 17alpha-ethynylestradiol (EE2) were obtained from human urine following ingestion of tritium-labeled EE2. Over 95% of the recovered activity was found as conjugated steroids and these were separated into four groups by chromatography of the urine extract on Sephadex LH-20 with chloroform-methanol (1/1) + 0.01M NaCl. The two major conjugate fractions appeared to be almost exclusively glucosiduronates. Enzymatic hydrolysis liberated at least ten different EE2 metabolites as shown by chromatography on Sephadex LH-20 with benzene-methanol (85/15). After additional separation and purification of these metabolites, positive identification was obtained for nine radioactive compounds by either gas liquid chromatography-mass spectrometry or reverse-isotope recrystallization. Five were ethynyl compounds: EE2, 2-MeO EE2, 16beta-OH EE2, 2-OH EE2 and 6alpha-OH EE2. The other four were de-ethynylated estrogens: estrone, estradiol-17beta, estriol, and 2-Me-O-estradiol-17beta.  相似文献   

6.
Combinations of 3 progestins, ethynodiol diacetate, norethynodrel and norgestrel, and 2 oestrogens, ethinyloestradiol and mestranol, were fed to larval Oregon-R fruit flies. None of the steroids studied induced X-linked recessive lethal mutations above the control level in Drosophila melanogaster.  相似文献   

7.
P Kim  M Hedman  B de la Torre  E Diczfalusy 《Steroids》1985,45(3-4):235-245
Litter-mate adult male rats were treated with daily intramuscular injections of ACTH (10.5 micrograms), dexamethasone (2.0 mg), ethynyl estradiol (1.7 micrograms) and hCG (5 IU) for three consecutive days. The animals were sacrificed on the fourth day and the intratesticular and peripheral plasma steroid levels were analyzed. The steroids measured by radioimmunoassay included pregnenolone, 17-hydroxypregnenolone, dehydroepiandrosterone, progesterone, 17-hydroxyprogesterone, androstenedione, testosterone and dihydrotestosterone. In addition, the sulphoconjugated forms of pregnenolone, dehydroepiandrosterone, testosterone and dihydrotestosterone were estimated in the peripheral blood. The administration of ACTH diminished the intratesticular levels of all steroids studied. Also dexamethasone and ethynyl estradiol treatment suppressed all intratesticular steroid levels, except that of pregnenolone (the former) and of 17-hydroxyprogesterone (the latter). The suppressive effect of ethynyl estradiol was strongest on the levels of the delta 5-steroids and that of dexamethasone on the delta 4-steroids; the latter was significantly stronger than the effect of ACTH. The stimulatory effect of hCG was limited to the metabolism of progesterone and was restricted to the sequence: 17-hydroxyprogesterone----androstenedione----testosterone---- dihydrotestosterone. Dexamethasone-suppression, and hCG-stimulation of the intratesticular levels of delta 4-steroids, was mirrored by corresponding changes in the peripheral plasma levels, with the exception of the plasma levels of androstenedione which were not influenced by any of the treatments studied. Also the suppression of intratesticular testosterone and dihydrotestosterone levels by ACTH, dexamethasone, or ethynyl estradiol was closely reflected by their plasma levels both in the unconjugated and sulphoconjugated forms. On the hand, the administration of ACTH diminished the intratesticular levels of pregnenolone and progesterone but significantly increased those in the plasma. Moreover, both ACTH and ethynyl estradiol reduced the levels of all delta 5-steroids in testicular tissue, but not in the peripheral plasma, although they decreased the circulating levels of pregnenolone sulphate and dehydroepiandrosterone sulphate. The data are interpreted as suggesting that the hormonal agents studied interfere with testicular steroidogenesis through different mechanisms.  相似文献   

8.
This study compares the binding of medroxyprogesterone acetate (MPA) and 17a-ethynyloestradiol to plasma proteins of various species (baboons, monkeys, dogs, rabbits, guinea-pigs, rats) with that in man. Plasma samples were collected from each species and subjected to centrifugation, filtration; equilibrium dialysis and polyacrylamide gel electrophoresis (PAGE). The results confirm the presence in the plasma of the species examined of a protein with a high capacity and low affinity for ethynyl estradiol and MPA. This protein appears to be the albumin. Ethynyl estradiol was bound to a greater extent than MPA in each species. There was a lack of binding of ethynyl estradiol to SHBG (sex hormone binding globulin) in any species, nor was binding reduced by dihydrotestosterone. This was attributed to a general steric effect of the introduction of the 17-alpha ethynyl group. It was also shown that more than 90% of ethynyl estradiol is loosely bound, mainly to serum albumin, with similar apparent association constants; in all species except dog and guinea-pig, binding occurred only to albumin. For MPA, less binding of MPA than ethinyl estradiol occurred in all species except the rabbit, and binding was significantly lower in the guinea-pig than in the other species. PAGE showed that binding occurred only to albumin. Stability of MPA-albumin complexes on PAGE varied and appeared to be less stable than the ethynyl estradiol-albumin complex. These variations in stability may account for the differences in biological activities of the steroids in different species.  相似文献   

9.
N- or C-terminal fusions of red-fluorescent protein (RFP) with various fungal cellulose-binding domains (CBDs) belonging to carbohydrate binding module (CBM) family 1 were expressed in a Pichia pastoris expression system, and the resulting fusion proteins were used to examine the feasibility of large-scale affinity purification of CBD-tagged proteins on cellulose columns. We found that RFP fused with CBD from Trichoderma reesei CBHI (CBD(Tr)(CBHI)) was expressed at up to 1.2g/l in the culture filtrate, which could be directly injected into the cellulose column. The fusion protein was tightly adsorbed on the cellulose column in the presence of a sufficient amount of ammonium sulfate and was efficiently eluted with pure water. Bovine serum albumin (BSA) was not captured under these conditions, whereas both BSA and the fusion protein were adsorbed on a phenyl column, indicating that the cellulose column can be used for the purification of not only hydrophilic proteins but also for hydrophobic proteins. Recovery of various fusion proteins exceeded 80%. Our results indicate that protein purification by expression of a target protein as a fusion with a fungal family 1 CBD tag in a yeast expression system, followed by affinity purification on a cellulose column, is simple, effective and easily scalable.  相似文献   

10.
Quantitative extraction and subsequent purification of small biological samples often involve cumbersome procedures. We have devised a short and efficient method for the quantitative extraction of the corticosteroid and the 20α reduced steroid series from culture medium containing 20% sera in a single, pure fraction with separation from cholesterol. Passage through a C18-bonded reversed-phase Sep-Pak® cartridge of the acidified culture medium and subsequent extraction of the steroid fraction with methanol yields a single fraction containing all steroids in 90% recovery and reduced quantities of cholesterol down to 30%. The extract can then be used without further purification for quantitative analysis by high-performance liquid chromatography or derivatized and analyzed by gas chromatography and gas chromatography—mass spectrometry.  相似文献   

11.
Guinea pig has a unique mammalian VIP   总被引:1,自引:0,他引:1  
Mammalian vasoactive intestinal peptide (VIP) has been reported to be identical in four species. This report describes the extraction of guinea pig (GP) intestinal VIP, its purification and sequence. Frozen intestines were extracted in five volumes of methanol and the methanol cakes reextracted with acid. VIP in the acid extract was concentrated onto ion-exchange cellulose and was brought to final purity through a series of HPLC steps. GP VIP differs from other mammalian VIP's by four amino acid substitutions: (sequence in text) This is further evidence that the GP gastroenteropancreatic axis has a unique evolutionary separation from other mammals.  相似文献   

12.
In this study, we evaluated four methods to separate and purify Toxoplasma gondii tachyzoites from in vivo and in vitro culture systems, including trypsin digestion, purification with a 3-μm filter, CF-11 cellulose purification, and Percoll purification. Our results indicate that both purification with a 3-μm filter and CF11 cellulose purification methods remove leukocytes or HeLa cells, and can therefore be used as candidate methods for the purification of in vivo and in vitro culture products. Trypsin digestion had a high tachyzoite recovery rate, but 22.35% of leukocytes and 69.64% of HeLa cells remained in the purified products. Percoll solution [30% (v/v)] also had a high tachyzoite recovery rate, but 3.44% of leukocytes and 61.61% of HeLa cells remained in the purified products. The 40% Percoll solution was also a candidate method for purifying tachyzoites from in vivo culture products, with a 65.45% tachyzoite recovery rate and without leukocytes.  相似文献   

13.
The use of the Ames test for the analysis of industrial effluents from cellulose production and sewage waters varying in the degree of purification with the aid of a metabolic activation system from rat and fish liver with Salmonella strains TA 98 and TA 100 revealed a strong direct mutagenic effect of strain TA 100 in samples after cellulose chlorination. The multistage procedure of sewage water purification allows to remove practically completely the mutagenic substances. A simultaneous study of cytotoxic effects of industrial effluents on mammalian cells shows that the mutagenic activity is exhibited in not toxic concentrations. The urgency of a regular biological control over the genotoxicity of industrial effluents from the sulfate production of cellulose is under discussion.  相似文献   

14.
《Process Biochemistry》2004,39(5):565-570
Expanded bed purification of α-amylase and cellulase directly from unclarified fermentation broth was carried out on specially prepared composite affinity matrices. The concept used was incorporation of polymeric substrates/substrate analogue during cross-linking of cellulose to prepare rigid, porous, cross-linked composite affinity matrices for target enzymes. Of the several polymeric substrates/substrate-analogue used, alginic acid (AA) and microcrystalline cellulose (MCC) when used to prepare cross-linked composite matrices with cellulose, resulted in best affinity purification matrices for α-amylase and cellulase, respectively. These matrices were suitable for purification of the enzymes by batch, packed bed as well as expanded bed purification protocols. The optimized expanded bed protocol for α-amylase from Bacillus spp. B3 gave 51-fold purification on AA-CELBEADS with 69% recovery, whereas, cellulase from Bacillus spp. B21 was purified on MCC-CELBEADS to 18-fold purification with 97% recovery. The SDS-PAGE of both purified preparations showed single bands indicating significant purification on composite affinity adsorbents in a single step strategy.  相似文献   

15.
The concentrations of triglyceride in the blood of female rats increased 2- and 4-fold during treatment with 5 and 15 mug/kg of ethynyl estradiol, respectively. The rate of secretion of triglyceride increased 66% over controls with livers obtained from the rats administered ethynyl estradiol. Ethynyl estradiol induced a hypocholesterolemia in the donor animals but the secretion of cholesterol into the perfusate from livers obtained from these animal was not affected. Adrenal corticosterone levels were depressed 48% in animals receivint of ethynyl estradiol on the liver or secondary to other hormonal changes.  相似文献   

16.
Summary Aspenwood, wheat straw, wheat chaff and alfalfa stems were treated under pressure with either steam or ammonia. The material was then water or methanol/water extracted. The extent of enzymatic hydrolysis of the cellulose portion of the treated substrates was compared using two different cellulases, a commercial preparation, Celluclast, and those from the fungus Trichoderma harzianum. Both steam and ammonia treatment enhanced the accessibility of the cellulose as measured by hydrolysis. Methanol extraction of steamed material generally reduced the access of the enzyme to the cellulose, whereas methanol extraction of ammonia-treated material increased accessibility. The optimum combinations of pretreatment and extraction method depended on the substrate and on the enzyme system; no treatment suitable for all situations could be selected.  相似文献   

17.
Chromatographic behaviour of rat-liver monophosphoinositide   总被引:2,自引:2,他引:0       下载免费PDF全文
1. Chromatography of rat-liver lipids on a column of silicic acid or a mixture of silicic acid and Hyflo Super-Cel, with chloroform–methanol mixtures, gave monophosphoinositide-containing fractions which were invariably contaminated by the presence of nitrogen-containing phospholipids. The behaviour of the inositide was extremely sensitive to column loading and the results with different batches of silicic acid were not reproducible. 2. However, when chromatography on an alumina column was used, the solvent system chloroform–methanol–water (23:23:4, by vol.) completely eluted the neutral lipids, choline-containing phospholipids and phosphatidylethanolamine. An increase of the water content of the solvent to 14% (by vol.) then led to the elution of the monophosphoinositide component, now free from nitrogen-containing phospholipids, but still contaminated by the presence of a phospholipid, which from its properties was taken to be polyglycerophosphatide. 3. Most of the polyglycerophosphatide could be removed from a rat-liver lipid extract by silicic acid chromatography with chloroform–methanol (19:1, v/v). The other phospholipids were then eluted and applied to an alumina column, whereby a monophosphoinositide fraction of much greater purity was obtained. 4. Further purification of the monophosphoinositide was achieved by chromatography on a mixture of silicic acid and cellulose powder. The final product was virtually pure by thin-layer chromatography and gave the expected analysis for monophosphoinositide.  相似文献   

18.
The effects of glucagon on the concentration and output of cAMP were studied in liver slices and in perfused livers from female rats and from animals treated with ethynyl estradiol (15 μg/kg daily for 14 days). The basal content of cAMP in liver slices, or of cAMP released into the perfusion medium in the absence of glucagon, was unaffected by prior treatment of the animal with estrogen. When glucagon was added to the medium, the concentration of cAMP in liver slices was 2.29 ± 0.32 and 1.10 ± 0.11 pmol cAMP/mg wet weight from control and ethynyl estradiol treated rats, respectively. When glucagon was added, the output of cAMP by perfused livers was maximal at 20 minutes with livers from either control or ethynyl estradiol treated rats. Output of cAMP by the perfused liver, when glucagon was added to the medium, was 8.76 ± 0.69 and 1.84 ± 0.08 nmol/g by livers from control and ethynyl estradiol treated rats, respectively. This effect was the same whether animals had been fasted for 12 hours previously, or were allowed free access to food until sacrifice. Clearly, as measured by cAMP accumulation, prior treatment of the rat with ethynyl estradiol reduced the sensitivity of the hepatic cAMP response to glucagon.  相似文献   

19.
Plasma membrane (PM) steroid recognition sites are thought to be responsible only for rapid, non-genomic responses without any link to the nuclear receptor-mediated genomic effects of steroids. We focused on a PM "glucocorticoid-importer" (GC-importer) that imports GC into rat liver cells. This site interacts also with particular gestagens (progesterone, P; medroxyprogesterone, MP; ethynodiol, Ethy) and estrogens (ethinylestradiol, EE(2); mestranol), which do not bind to the nuclear GC receptor (GR). To elucidate the role of the GC-importer, we transfected a rat wild-type hepatocyte (CC-1) and a hepatoma cell line, unable to import GC (MH 3924), with a GC<-->GR-responsive luciferase (luc)-reporter gene. Selected steroids were tested for their ability to induce or inhibit luc expression. Corticosterone (B) and dexamethasone (Dex), but also the GC-antagonists cortexolone (Cortex), P and MP, induced luc. Even the PM-impermeable BSA-derivatives of B, Dex and Cortex did so to almost the same extent as the free steroids. MH 3924 cells respond stronger than CC-1 to luc inducing steroids. Luc expression was inhibited by RU 38 486, but also by EE(2) and Ethy. The thiol reactive mesylate-derivatives of B, Dex and Cortex induced to a considerably lesser extent than the free or BSA-steroids. The thiol reagent mersalyl blocks cellular entry of GC and inhibits luc induction in CC-1 cells. Incubation with EE(2) and B of PM-vesicles, isolated from liver cells, resulted in a decrease of the density of two 75 and 52kDa G-proteins reflecting a diminished exchange of GDP by GTP. CONCLUSION: the PM-residing GC-importer, now renamed "Steroid Hormone Recognition and Effector Complex" (SHREC) is an interdependent part of the complete GC signal propagation in which G-proteins are involved. Free SH-groups of SHREC are a prerequisite for genomic GC activity. Specific interactions between SHREC and GC-agonist/-antagonist trigger steroid-dependent signaling. However, import of the ligand into the cell terminates it. Thus, the PM-related non-genomic steroid responses are clearly linked to the GR-related genomic effects.  相似文献   

20.
Centrifugal liquid-liquid partition chromatography presents significant advantages for the separation and purification of plant metabolites owing to the short operational time of the process and the elimination of possible irreversible adsorption of compounds. The crude chloroform extract from roots of Plumbago auriculata was analysed by countercurrent chromatography using hexane:ethyl acetate:methanol:water (40:10:10:2, v/v) as solvent system. The isolation of the naphthoquinones plumbagin and epi-isoshinanolone, the steroids sitosterol and 3-O-glucosylsitosterol, plumbagic and palmitic acids was easily achieved. Naphthoquinones are typical components of Plumbago species and they show interesting biological activities.  相似文献   

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