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1.
Dehydroepiandrosterone, testosterone and progesterone 7-carboxymethyl derivatives were prepared : 7α and 7β epimers were separated and coupled to bovine serum albumin. Preliminary studies of the antisera induced by these antigens showed that they have high affinity and good specificity.  相似文献   

2.
Aromatase activity and concentrations of cortisol, progesterone and testosterone were measured in samples of breast and abdominal adipose tissue obtained from both pre- and postmenopausal subjects. Enzyme activity was determined by the incorporation of tritium from [1 beta-3H]androstenedione into water and found to be in close agreement to that measured when tritium labelled oestrone (E1) and oestradiol (E2) were isolated. No significant difference in enzyme activity was noted between breast and abdominal adipose tissue. Increased aromatase activity was not observed in adipose tissue taken from a subject with endometrial cancer. Cortisol concentrations were found to be significantly higher (P less than 0.05) in abdominal as compared to breast tissue. Without attaining statistical significance progesterone concentrations were higher in abdominal as compared to breast adipose tissue. Aromatase activity was not related to either cortisol or testosterone tissue concentration, but an inverse relationship between progesterone concentration and aromatase activity was observed (r = 0.542, P less than 0.02). On the basis of results obtained a hypothesis for the increased conversion of androgen to oestrogen as seen after the menopause has been proposed.  相似文献   

3.
Synthesis and anticancer activity of thiosemicarbazones   总被引:3,自引:0,他引:3  
Twenty-six thiosemicarbazones (III-1-III-26) were synthesized via three steps starting from hydrazine hydrate and carbon disulfide. The testing of anticancer activity of these compounds in vitro against P-388, A-549, and SGC-7901 shows that compounds III-15 and III-16 possess a higher inhibitory ability for P-388 and SGC-7901. Further testing shows that the value of IC50 of compound III-16 against SGC-7901 reaches to 0.032 microM.  相似文献   

4.
It was found that testosterone propionate (3 mg/kg of body weight) and progesterone (1 mg/kg of body weight) partially prevent an augmentation of the carboxypeptidase H activity in the mouse pituitary gland under stress caused by a single intraperitoneal administration of olive oil. In testicles, testosterone prevented augmentation of the enzyme activity within 0.5 hours but increased it through in 4 and 24 hours after treatment. Progesterone in testicles augmented the enzyme activity within 0.5 hours, but not in 4 and 24 hours. Sex steroids were not affected by stressinduced carboxypeptidase H activity in hypothalamus and adrenal medulla. It was concluded that carboxypeptidase H did not take part in integration of hypothalamus-pituitary-adrenal and hypothalamus-pituitary-gonadal axis under the stress.  相似文献   

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Plasma concentrations of testosterone, androstenedione and progesterone in freemartins, and normal cyclic and non-cyclic heifers were studied. The plasma testosterone concentrations were in general less than 10 pg/ml in all animals. The mean androstenedione concentration of 28 pg/ml in 10- to 12-month-old freemartins was significantly lower than the mean of 58 to 60 pg/ml for normal 10- to 12-month-old heifers. At 24 months of age the mean androstenedione concentration in the freemartins had risen significantly to 65 pg/ml.  相似文献   

8.
The strain of Absidia coerulea was used to investigate the transformations of testosterone, androstenedione, progesterone and testosterone derivatives with additional C1–C2 double bond and/or 17-methyl group. All the examined substrates were transformed, mainly hydroxylated. It was found that the position and stereochemistry of the introduced hydroxyl group, as well as the yield of products, depended on the structure of the substrate. The first three substrates (hormones) underwent hydroxylation at C-14, and additional hydroxylation at 7 was observed in progesterone. The presence of the double bond (C1–C2) in 1-dehydrotestosterone did not influence the position of hydroxylation, but the product with additional C14–C15 double bond (at the same site as hydroxylation) was formed. 17-Methyltestosterone was hydroxylated at the 7 position, and also the dehydrogenated product (at the same site, with C6–C7 double bond) was obtained. The testosterone derivative with both C1–C2 double bond and 17-methyl group underwent hydroxylation at the 7 or 11β position, and a little amount of 14, 15 epoxide was formed.  相似文献   

9.
Steroidal thiosemicarbazones, semicarbazones and hydrazones have received extensive attention of scientists recently because they exhibit some biological activities such as antibacterial, antiviral and anticancer. Using different steroids as starting materials, through different chemical methods, 24 steroidal compounds with thiosemicarbazone, semicarbazone or hydrazone groups in their structures, were synthesized, characterized by IR, NMR and MS. The antiproliferative activity of the compounds was evaluated against human gastric cancer (SGC-7901) and human liver cancer (Bel-7404) cells. The structure–activity relationship of these compounds was discussed. The results showed that compound 3 and 12a12c exhibited significant inhibitory activity to Bel-7404 cells, and IC50 values of them were 4.2, 11.0, 7.4 and 15.0 μM respectively (Cisplatin, IC50: 11.6 μM).  相似文献   

10.
Malaria is a devastating illness caused by multiple species of the Plasmodium genus. The parasite’s falcipain proteases have been extensively studied as potential drug targets. Here we report the testing of two established cysteine protease inhibitor scaffolds against both chloroquine sensitive and chloroquine resistant parasites. A subset of purine derived nitriles killed the parasite with moderate potency, and these inhibitors do not seem to exert their antiproliferative effects as cysteine protease inhibitors. Compound potency was determined to be similar against both parasite strains, indicating a low probability of cross resistance with chloroquine. These compounds represent a novel antimalarial scaffold, and a potential starting point for the development new inhibitors.  相似文献   

11.
Ribonucleotide reductase (RR) is an important therapeutic target for anticancer drugs. The structure of human RR features a 1:1 complex of two homodimeric subunits, hRRM1 and hRRM2. Prokaryotically expressed and highly purified recombinant human RR subunits, hRRM1 and hRRM2, were used for holoenzyme-based [(3)H]CDP reduction in vitro assay. Ten new thiosemicarbazones (7-16) were synthesized and screened for their RR inhibitory activity. Two thiosemicarbazones derived from p-hydroxy benzaldehyde (9 and 10) were found to be active but less potent than the standard, Hydroxyurea (HU). Guided by the activity of compounds 9 and 10, 11 new thiosemicarbazones (17-27) derived from p-hydroxy benzaldehyde were prepared and screened for their RR inhibitory activity. All the 11 compounds were more potent than HU.  相似文献   

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13C and 1H NMR relaxation rates were measured for the glutathione-VO2+ 2:1 complex in aqueous solution. The kinetics of the dissociation of the peptide from the coordination sphere were delineated and the structure of the complex was determined. The two carboxyl groups were shown to be the main binding sites.  相似文献   

14.
Peripheral plasma concentrations of progesterone, total oestrogens and testosterone (measured by RIAs) and LH (monitored by the mouse Leydig cell bio-assay) were measured in 8 female camels for a complete oestrous cycle (23.1 +/- 1.2 days). The absence of an LH surge and a low concentration of progesterone (less than 1 ng/ml) during oestrus (5 days) and throughout the cycle indicated a failure of spontaneous ovulation and absence of a subsequent luteal phase in this species. High concentrations of testosterone and oestrogens indicated that the oestrous cycle in the camel is mostly follicular and that the increasing values of the two hormones during follicular development (5 days) is probably the stimulus to behavioural oestrus.  相似文献   

15.
E. Nieschlag 《Andrologie》2012,22(3):136-140
The world population continues to grow rapidly while resources for sustainable living dwindle and manmade ecological problems increase proportionally to the overpopulation. Family planning is required to reduce population growth in developing countries and to stabilize populations in developed countries. Contraception makes abortion superfluous and provides the key to family planning. Women increasingly demand that men share the burden and risks of contraception and ?? as opinion polls show ?? men would be willing to use contraceptives if they were available. Research has established the principle of hormonal male contraception based on suppression of gonadotropins and spermatogenesis. All hormonal male contraceptives use testosterone, but in East Asian men, testosterone alone can suppress spermatogenesis to a level compatible with contraceptive protection. In Caucasians additional agents are required of which progestins are favoured.  相似文献   

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The influence of estrogen, progesterone and testosterone on the activities of alkaline and acid phosphatases, adenosine triphosphatase and succinate dehydrogenase were determined by cytochemical methods in sarcoma 180 and Ehrlich's carcinoma cells transplanted in male and female Swiss mice. The results revealed differential effects of the sex hormones on different enzymes which seemed to depend on the type of tumour cell studied and the sex of the host mice.  相似文献   

19.
Parthenolide is an important sesquiterpene lactone with potent anticancer activities. In order to further improve its biological activity, a series of parthenolide semicarbazone or thiosemicarbazone derivatives was synthesized and evaluated for their anticancer activity. Derivatives were tested in vitro against 5 human tumor cell lines, and many of these showed higher cytotoxicity than parthenolide. Five compounds were further studied for their antitumor activity in mice. The in vivo result indicated that compound 4d showed both promising antitumor activity against mice colon tumor and small side effects on immune systems. The cell apoptosis and cell cycle distribution of compound 4d were also studied. Molecular docking studies revealed multiple interactions between 4d and NF-κB. Our findings demonstrate the potential of semicarbazones as a promising type of compounds with anticancer activity.  相似文献   

20.
Thiosemicarbazides and their analogs have shown potential medical applications as antiviral, antibacterial and anticancer drugs. We designed, synthesized and evaluated in vitro anticancer activity against ovarian (A2780), cervix (HeLa), colon (LoVo), breast (MCF-7) and brain (MO59J) human cancer cell lines of seven novel compounds –S-glycosylated thiosemicarbazones. We assessed the cyto- and genotoxic properties of all novel compounds using a variety of methods including comet assay, XTT assay, various fluorescent assays and toxicology PathwayFinder expression array. We tried to evaluate their possible mechanism of action with particular attention to induction of DNA damage and repair, apoptosis, oxidative stress analysis and cellular response in terms of changes in gene expression. The most sensitive cell line was human ovarian cancer. The results revealed that the major activity against A2780 cancer cell line displayed by our compounds is induction of DNA damage. This effect is not associated with apoptosis or oxidative stress induction and the resulting damage will not lead to cell cycle arrest. We also observed up-expression of heat shock related genes and NQO1 gene in response to our compounds. The second effect seems to be specific to glycosylated S-bond compounds as we observed it earlier. Upregulation of heat shock protein encoding genes suggest that our compounds induce stressful conditions. The nature of this phenomena (heat shock, pH shift or hypoxia) needs further study.  相似文献   

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