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The preparation of (3,3,4,4-D4)-PGE2, (3,3,4,4-D4)-PGF, (3,3,4,4-D4)-9α,11α-dihydroxy-15-ketoprost-5-enoic acid and (3,3,4,4-D4)-9α,11α,15-trihydroxyprost-5-enoic acid is described. These compounds have been used for quantitative determination of corresponding nondeuterated prostaglandins by gas-liquid chromatography-mass spectrometry. The method is based on addition of a known amount of carrier to the sample and after purification and derivatization the ratio between the protium and deuterium form is measured in the mass spectrometer. Ions originating in deuterated and nondeuterated molecules are focused one at a time on the electron multiplier using an accelerating voltage alternator.With this technique 400 pg of PGF can be determined with a precision of ±3.7% (SD). The recoveries from plasma samples, containing 1–2.5 ng/ml of any of the compounds, is about 100±10%.  相似文献   

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During the early stages of germination, a lipid-body lipoxygenase is expressed in the cotyledons of sunflowers (Helianthus annuus L.). In order to obtain evidence for the in vivo activity of this enzyme during germination, we analyzed the lipoxygenase-dependent metabolism of polyunsaturated fatty acids esterified in the storage lipids. For this purpose, lipid bodies were isolated from etiolated sunflower cotyledons at different stages of germination, and the storage triacylglycerols were analyzed for oxygenated derivatives. During the time course of germination the amount of oxygenated storage lipids was strongly augmented, and we detected triacylglycerols containing one, two or three residues of (9Z,11E,13S)-13-hydro(pero)xy-octadeca-9,11-dienoic acid. Glyoxysomes from etiolated sunflower cotyledons converted (9Z,11E,13S)-13-hydroxy-octadeca-9,11-dienoic acid to (9Z,11E)-13-oxo-octadeca-9,11-dienoic acid via an NADH-dependent dehydrogenase reaction. Both oxygenated fatty acid derivatives were activated to the corresponding CoA esters and subsequently metabolized to compounds of shorter chain length. Cofactor requirement and formation of acetyl-CoA indicate degradation via -oxidation. However, -oxidation only proceeded for two consecutive cycles, leading to accumulation of a medium-chain metabolite carrying an oxo group at C-9, equivalent to C-13 of the parent (9Z,11E,13S)-13-hydroxy-octadeca-9,11-dienoic acid. Short-chain -oxidation intermediates were not detected during incubation. Similar results were obtained when 13-hydroxy octadecanoic acid was used as -oxidation substrate. On the other hand, the degradation of (9Z,11E)-octadeca-9,11-dienoic acid was accompanied by the appearance of short-chain -oxidation intermediates in the reaction mixture. The results suggest that the hydroxyl/oxo group at C-13 of lipoxygenase-derived fatty acids forms a barrier to continuous -oxidation by glyoxysomes.  相似文献   

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C-15 epimers of 15-hydroxy-15-methyl-9-oxoprostanoic acid (AY-22,469), administered perorally, were similar in activity to AY-22,469 in inhibiting basal gastric acid secretion and ulcer formation induced by pylorus ligation in the rat. For these prostaglandin analogues the stereochemistry at C-15 does not appear to be of importance with respect to these activities.  相似文献   

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3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholest-24-enoic acid, formed in the peroxisomal oxidation of 3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholestanoyl-CoA by the THCA-CoA oxidase in rat liver, was isolated and purified on reverse phase HPLC. The configuration of the C-24/25 double bond was determined to be trans (E) by using 1H-NMR spectrometry.  相似文献   

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Stereoselective synthesis of a promising flower-inducing 9,10-ketol octadecadienoic acid (KODA) analog, (9R,12S,13R,15Z)-9-hydroxy-12,13-methylene-10-oxooctadec-15-enoic acid, was designed to obtain the desired stereoisomer via coupling between chiral sulfone and aldehyde segments. A known chiral cyclopropane derivative was converted to the sulfone segment via carbon-chain elongation and sulfonylation. Dec-9-en-1-ol was converted to the aldehyde segment, whose C-9 configuration was introduced by Sharpless asymmetric dihydroxylation. Coupling of the both segments and subsequent assembly gave the desired (9R,12S,13R,15Z)-analog. The (9S,12S,13R,15Z)-analog was also synthesized by using the enatiomeric aldehyde segment. This strategy made it possible to synthesize the remaining stereoisomeric analogs.  相似文献   

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A 42-cM map of proximal mouse chromosome 9, including eight loci defined by restriction fragment length variants, has been generated. Linkage was established by haplotype analyses of 114 interspecific backcross mice and indicated the following gene order: (centromere) Pvs-5.3 cM-Icam-1/Ldlr-18.4 cM-Thy-1-1.8 cM-Ncam-0.9 cM-Hexa-7.9 cM-Gsta-7.9 cM-Trf. Three of these loci, Pvs, Icam-1, and Hexa, have not been mapped previously. Together with previous mapping studies the current results suggested that chromosomal segments of mouse chromosomes 7 and 9 and chromosomal segments of human chromosomes 11, 15, and 19 derive from a single putative primordial chromosome. The studies support the postulate that detailed analysis of chromosome organization will be useful in defining events in mammalian evolution.  相似文献   

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IgG1 monoclonal antibody to purified seminal fluid phosphatase was raised by fusion of spleen cells from immunized mice with cell line Sp2/O-Ag 14 using simple method of screening for antiphosphatase antibody secreting clones. All molecular forms of catalytically active seminal fluid phosphatase and prostatic tissue phosphatase, resolved by chromatofocusing in pH gradient, react with this monoclonal antibody and with rabbit antiserum to purified seminal fluid phosphatase. Peptides of Mr 25,000 to 76,000 and of Mr 13,000 to 76,000 were adsorbed from the prostatic tissue extract and from seminal plasma on the monoclonal antibody-Sepharose column.  相似文献   

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A creatine kinase assay based on estimation of creatine liberated from creatine phosphate was accurate and reproducible for use with seminal or prostatic fluid, after allowance was made for acid phosphatase interference. Comparison of this method with one which relies on enzymic coupling of ATP formation to NADP+ oxidation shows that the latter under-estimates creatine kinase activity by a factor of about 3. This discrepancy could be due to the high ATPase activity found in prostatic and seminal fluid. Uncritical use of the NADP+ assay might account for different seminal creatine kinase values reported in the literature. Interrelationships between ATPase, creatine kinase and zinc suggest that seminal ATPase is a prostatic secretory product while creatine kinase may be multiglandular in origin.  相似文献   

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A monoclonal antibody with anti-sialyl-lacto-N-fucopentaose II specificity, originally thought to be a specific tumor marker in pancreas- and gastrointestinal tumors, reacts strongly with fucose-rich glycoproteins from human seminal plasma obtained by phenol/saline extraction. They are presumed to come from the prostatic gland secretion. Because of the specificity of this monoclonal antibody it can be deduced that the sialyl-Lea-sequence: N-acetyl-alpha-neuraminyl-(2----3)-beta-D-galactopyranosyl-(1--- -3)-[alpha-L-fucopyranosyl-(1----4)]-2-acetamido-2-deoxy-beta-D-gluco pyranosyl-(1----3)-D-galactopyranosyl is present on these glycoproteins. This is also supported by our carbohydrate analysis.  相似文献   

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Two Lifschütz-positive C24-bile acids were isolated from bladder bile of hens. One of these was identified by isotope dilution experiments after conversion to a 3H-labeled compound, and also by GLC after methoxylation, as 3beta,7alpha-dihydroxychol-5-enoic acid, a key intermediate of chenodeoxycholic acid biogenesis. The other, to which the structure 3beta,7alpha-dihydroxychol-4-enoic acid had been assigned previously, was proved to be its 3alpha-epimer by several experiments. These findings favor the alternative pathway of chenodeoxycholic acid biogenesis proposed by Yamasaki and his associates.  相似文献   

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Several grams of labelled trans linoleic and linolenic acids with high chemical and isomeric purities (>97%) have been prepared for human metabolism studies. A total of 12.5 g of (9Z, 12E)-[1-(13)C]-octadeca-9,12-dienoic acid and 6.3 g of (9Z,12Z, 15E)-[1-(13)C]-octadeca-9,12,15-trienoic acid were obtained in, respectively, seven steps (7.8% overall yield) and 11 steps (7% overall yield) from 7-bromo-heptan-1-ol. The trans bromo precursors used for the labelling were synthesised by using copper-catalysed couplings. The trans fatty acids were then obtained via the nitrile derivatives. A total of 23.5 g of (9Z,12Z)-[1-(13)C]-octadeca-9, 12-dienoic acid and 10.4 g of (9Z,12Z,15Z)-[1-(13)C]-octadeca-9,12, 15-trienoic acid were prepared in five steps in, respectively, 32 and 18% overall yield. Large quantities of bromo and chloro precursors were synthesised from the commercially available acid according to Barton's procedure. In all cases, the main impurities (>0.5%) of each labelled fatty acid have been characterised.  相似文献   

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11 alpha-Hydroxy-9,15-dioxo-2,3,4,5,20-pentanor-19-carboxyprostano ic acid (PGE-M) and 9 alpha,11 alpha-dihydroxy-15-oxo-2,3,4,5,20-pentanor-19-carboxyprostanoic acid (PGF-M) in urine were determined in an isotope dilution assay by gas chromatography/triple-stage quadrupole mass spectrometry. After addition of the 2H7-labeled internal standard, O-methylhydroxylamine hydrochloride in acetate buffer was added either directly (PGE-M) or after standing overnight at pH 10 (PGF-M) to form the methoxime. The sample was acidified to pH 2.5 and PGE-M and PGF-M were extracted with ethyl acetate/hexane. Then the prostanoids were derivatized to the pentafluorobenzyl ester and purified by thin-layer chromatography and the trimethylsilyl ether was formed. The products were quantified by gas chromatography/triple-stage quadrupole mass spectrometry. For PGE-M, the fragment ions m/z 349 and m/z 356 (2H7 standard) (daughter ions of m/z 637 and m/z 644 (2H7 standard] were used. The results of the PGE-M assay were compared with those of an assay using the [2H3]methoxime as the internal standard. For determination of PGF-M, the daughter ions m/z 484 and m/z 491 (2H7 standard) with the parent ions m/z 682 and m/z 689 (2H7 standard) were chosen.  相似文献   

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