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1.
S.A. Sholl  R.C. Wolf 《Steroids》1980,36(2):209-218
For the purpose of describing the pathway by which estrogens are synthesized in the rhesus monkey (Macacamulatta) corpus luteum (CL), CL were obtained during the midluteal phase of the menstrual cycle and fragments incubated with equimolar amounts of [7-3H]pregnenolone plus [4-14C]progesterone. Metabolites including 3H-progesterone, 3H, 14C-20α-dihydroprogesterone, 3H, 14C-17-hydroxyprogesterone, 3H-estrone and 3H-estradiol-17β appeared in the medium during the first 20 minutes of incubation, 3H, 14C-Androstenedione was not consistently noted until after 60 minutes. Despite the fact that the 14C/3H-17-hydroxyprogesterone ratio quickly approached a constant value in the medium, 14C-estrogens were not detected in the medium or tissue fragments suggesting that progesterone was not a principal precursor for estrogen synthesis. As evidenced by the observation that the 14C/3H-progesterone ratio was significantly higher in luteal fragments than the 17-hydroxyprogesterone ratio, 17-hydroxyprogesterone appeared to be synthesized from pregnenolone both by way of progesterone and by another route which did not include progesterone. C21- and C18-Steroids were more concentrated in tissue fragments after 120 minutes of incubation than in the medium indicating that these steroids were sequestered by luteal tissue.  相似文献   
2.
Under the protection of ascorbic acid a 2-hydroxyestrone bovine serum albumin conjugate was prepared containing intact 2-hydroxyestrone as determined by gas chromatographymass spectrometry. Using this antigen highly specific antibodies were raised in rabbits. Cross-reactivity for 2-hydroxyestradiol and 2-hydroxyestriol was 26 and 4.5%, respectively. An assay procedure of 2-hydroxyestrone in human plasma is described. Using special precautions the assay allows the determination of 2-hydroxyestrone in plasma samples of women (50–95 pg/ml), pregnant women (105–220 pg/ml), men (45–65 pg/ml) and children (20–40 pg/ml).  相似文献   
3.
Bryan MB  Scott AP  Cerný I  Young BA  Li W 《Steroids》2004,69(7):473-481
There is growing evidence that sea lampreys, Petromyzon marinus L., produce gonadal steroids differing from those of other vertebrates by possessing an additional hydroxyl group at the C15 position. Here we demonstrate that sea lamprey testes produce 15alpha-hydroxyprogesterone (15alpha-P) in vitro when incubated with tritiated progesterone, that 15alpha-P is present in the plasma of sea lampreys, and that plasma concentrations of immunoreactive (ir) 15alpha-P rise dramatically in response to injections of gonadotropin-releasing hormone (GnRH). The identity of the tritiated 15alpha-P produced in vitro was confirmed by co-elution with standard 15alpha-P on high performance liquid chromatography, co-elution with standard and acetylated 15alpha-P on thin layer chromatography, and specific binding to antibodies raised against standard 15alpha-P. The in vitro conversion was used to produce tritiated 15alpha-P label for a radioimmunoassay (RIA), which is able to detect 15alpha-P in amounts as low as 2 pg per tube. The RIA has been used to measure the plasma concentrations of 15alpha-P in males given two serial injections, 24 h apart, of either lamprey GnRH I or GnRH III (50, 100, or 200 microg/kg) or saline control, with plasma being sampled 8 and 24 h after the second injection. Plasma concentrations of ir-15alpha-P rose from < 1 to 36 ng/ml (mean of all treatments) 8 h after injection and declined within 24 h. This is the first time that an RIA has detected such high steroid concentrations in lampreys. This finding is suggestive of a role for 15alpha-P in control of reproduction in the sea lamprey.  相似文献   
4.
Available data indicate that progesterone is able to treat pregnancy-induced hypertension (preeclampsia). Dydrogesterone and 17alpha-hydroxyprogesterone caproate might also be used for this purpose. Prevention of hypertensive disorders in preeclampsia also seems possible, but studies are needed to confirm this.  相似文献   
5.
Ralph Fingerhut 《Steroids》2009,74(8):662-1442

Background

While the sensitivity of newborn screening for the salt wasting form of congenital adrenal hyperplasia (CAH) is good, the positive predictive value is poor due to the high false positive rate of the immunological assays for 17-OHP. Cross-reactivity with steroid sulfates is one of the main causes for false positive results. Several approaches have been described to improve CAH screening: adjusting cut-off levels to gestational age or birth weight, and second-tier molecular genetic analysis or second-tier liquid chromatography-tandem mass spectrometry (TMS).

Methods

17-OHP was extracted with diethyl ether from dried blood spots in order to separate 17-OHP from polar steroids (like steroid sulfates). The dried ether extracts of calibrators, controls, and patient samples were redissolved and measured with the 17-OHP test kit (Wallac).

Results

760 normal, 1049 false positive, and 232 samples of confirmed cases with CAH were analysed. Mean 17-OHP values were significantly lower after extraction: Normal samples: 17.5 nmol/L vs. 3.2 nmol/L; false positive samples: 97.0 nmol/L vs. 25.9 nmol/L; CAH: 275 nmol/L vs. 205 nmol/L. With a cut-off value of 11.9 nmol/L (mean + 3 SD of the normal values), 404 of the false positives turned out to be normal. Ether extraction revealed two distinct subgroups of initially false positives rather than a continuum with normal distribution of 17-OHP values.

Conclusion

Diethyl ether extraction provided evidence for two causes of false positive results in CAH screening. It reduced the rate of false positives by about 40% without loss of sensitivity.  相似文献   
6.
An enhancement of 17α-hydroxyprogesterone (17α-HP) production from progesterone by biotransformation using hydroxypropyl-β-cyclodextrin (HPβCD) complexation together with aeration and sonication technique was demonstrated. The progesterone–hydroxypropyl-β-cyclodextrin complex was prepared by co-evaporation method. The percentage yield of 17α-HP from P of 11.26 ± 0.64% at 24 h was observed in Curvularia lunata ATCC 12017. In the complex form of P, together with sonication at 40 kHz for 5 s and aeration, the yield of 17α-HP was increased to 72.92 ± 4.28% which was about 6.5 and 1.3 times of that from the uncomplexed (P) and the complexed (PC), respectively without sonication and aeration. The increased aqueous solubility of P by complexation with HPβCD was the main factor which increased the yield of 17α-HP, while aeration had more effect on P than PC. Sonication did not significantly increased the yield of the product from both P and PC. When both aeration and sonication were used in the PC system, the product yield was increased significantly more than that from P. The result from this study can be applied for the biotransformation of other poor aqueous soluble precursors.  相似文献   
7.
Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency is a common autosomal recessive disorder. Ornithine transcarbamylase (OTC) deficiency is the most common urea cycle disorder and demonstrates X-linked inheritance. In female OTC deficiency, phenotypes are variable according to X-inactivation patterns. These disorders develop separately, and their co-morbidity is extremely rare. We report one girl with CAH showing recurrent hyperammonemia and hepatitis after 2 years-of-age due to additional OTC deficiency.  相似文献   
8.
Pteropyrum scoparium Jaub. & Spach (Polygonaceae) is a naturally growing shrub used as food crop in Oman. The chemical investigation of the ethyl acetate extracts of the leaf afforded phenylethanoid, benzofuranylethanoid and ethyl esters of caproic and lauric acids (1–3), proanthocyanidin trimer epicatechin-3-O-gallate-(4  8)-epicatechin-3-O-gallate-(4  8)-epicatechin-3-O-gallate (4) and epicatechin-3-O-gallate (5). Compounds 1 and 3 are new and isolated for the first time from P. scoparium. The structures of compounds were assigned based on 1D and 2D NMR spectroscopy and ESI–MS analysis. Compounds 1 and 3 were tested for free radical scavenging anti-oxidant properties and found to inhibit 2,2′-diphenyl-1-picrylhydrazyl radical (DPPH) by 1.7% and 41.0%, respectively compared to 71% and 78% for gallic acid and butylated hydroxyanisole used as control.  相似文献   
9.
以少根根霉 (Rhizopusarrhizus)脂肪酶为催化剂 ,有机溶剂为反应介质 ,合成了 3种短链脂肪酸酯 .研究了反应温度、溶剂、底物浓度、底物摩尔比、吸水剂用量等因素对酯化反应的影响 .确定了3种酯的最佳合成条件 :(1)己酸乙酯 :反应温度为 4 0℃ ,环己烷为溶剂 ,0 2 5mol L底物浓度 ,酸醇摩尔比为 1∶1 2 ;(2 )乙酸异丙酯 :5 0℃ ,环己烷为溶剂 ,0 15mol L底物浓度 ,摩尔比为 1∶1;(3)乙酸异戊酯 :5 0℃ ,异辛烷为溶剂 ,0 2 0mol L底物浓度 ,摩尔比为 1∶1.三种酯合成时均需 0 12 5g ml的0 5nm分子筛为吸水剂 ,在 8h后 ,合成酯转化率达到 97%~ 99% .  相似文献   
10.
红曲霉胞外脂酶催化己酸乙酯合成研究   总被引:11,自引:0,他引:11  
己酸乙酯是浓香型曲渣的主体香昧成分,也是曲酒优质品率低的主要限制因素。60年代Iwai⑴发现在适当条件下脂酶可直接催化酸和醇合成酯。Langrand⑵比较了各种脂酶合成短碳链羧酸酯的能力。我们在对酒窖生香微生物的研究中发现红曲霉、根霉具有较强的己酸己酯合成能力,属首次报道⑶。本文主要报道利用红曲霉的脂酶合成己酸乙酯条件试验的结果。  相似文献   
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