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81.
A method of the microdetermination of delta 17-6-keto-PGF1 alpha, a hydrolyzed metabolite of PGI3, is described. An authentic delta 17-6-keto-PGF1 alpha (120 mg) was prepared from eicosapentaenoic acid (EPA) incubated with homogenate of bovine aortic intima. [18O]delta 17-6-Keto-PGF1 alpha was synthesized by repeating base-catalyzed hydrolysis of methyl ester derivatives in [18O]water, to obtain an internal standard in gas chromatography/selected ion monitoring (GC/SIM) of delta 17-6-keto-PGF1 alpha. Good linear response over the range of 10 pg-10ng was demonstrated. Chromatographic conditions using a MP-65HT column presented nearly baseline separation of delta 17-6-keto-PGF1 alpha and 6-keto-PGF1 alpha. We were able to detect delta 17-6-keto-PGF1 alpha in the range from 6 to 26 pg/ml of the human plasma. The present method can be applied to the determination of delta 17-6-keto-PGF1 alpha in the human urine and plasma.  相似文献   
82.
A monoclonal antibody against cis-3-hexen-1-ol was prepared and used to separate and/or concentrate delta 17-6-keto-prostaglandin F1 alpha (PGF1 alpha) in the human sera. cis-3-Hexen-1-ol was conjugated with the human serum albumin (HSA) according to the N-succinimidylester method and hyperimmunized to BALB/c mouse. The monoclonal antibodies were obtained from hybridoma clones established by a fusion between SP2/0-Ag14-k13 mouse myeloma cells and splenocytes of a mouse. A monoclonal antibody, named 4G9-12B, recognized the epitope characteristic for omega 3-olefin structure. The 4G9-12B antibody became more specific for delta 17-6-keto-PGF1 alpha than 6-keto-PGF1 alpha by applying inhibition ELISA using amino-residue coating plates. Using the prepared immunoaffinity columns of this antibody, delta 17-6-keto-PGF1 alpha was clearly detected in 6 pg/ml of the human blood sera by GC/MS analysis. These results suggest that the monoclonal antibody to the partial structure of trienoic prostanoid, omega 3-olefin unit, and that its immunoaffinity columns are useful in separating and concentrating delta 17-6-keto-PGF1 alpha in the human blood or urine.  相似文献   
83.
Verbascoside was found to be produced in all calli derived from eleven species that contained the compound in their leaves. Cell suspension cultures were also established in three species, i.e., Leucosceptrum japonicum f. barbinerve, Syringa josikaea, and Sy. vulgaris, all of which were found to produce verbascoside at more than 1 g/l. Of the three species, suspension cultures of L. japonicum f. barbinerve showed rapid growth and the highest yield of verbascoside (1.89 g/l). In these cultures, the effects of major salt concentration in B5 medium on cell growth and verbascoside production were examined. Maximum cell growth and maximum verbascoside production were both achieved by reducing the major salt concentration to half that of the original medium.  相似文献   
84.
Summary Genetically transformed kiwi fruit (Actinidia deliciosa) plants were obtained from hypocotyl and stem segments co-cultured with Agrobacterium tumefaciens strain EHA101 harboring a binary vector, pLAN411 or pLAN421, which contained the neomycin phosphotransferase II (nptII) gene and the -glucuronidase (GUS) gene. After co-culturing with the A. tumefaciens, the hypocotyl or stem segments were cultured on a selection medium containing 25g/ml kanamycin and 500g/ml Claforan. After one month in culture, shoots had regenerated from the cuttings. Green shoots were analyzed for NPTII activity and GUS activity. Eighty-five percent of the green shoots examined expressed the nptII and GUS genes. GUS histochemical assays revealed strong GUS expression in guard cells, mesophyll cells, and trichomes.  相似文献   
85.
A sialoglycoprotein and a fucose sulfate glycoconjugate (FSG) were purified from egg jelly of the sea urchin Hemicentrotus pulcherrimus . Sialoglycoprotein which consisted of sialic acid (90%, w/w) and protein (10%, w/w) did not cause induction of the acrosome reaction and sperm isoagglutination. FSG which contained one mol sulfate/mol fucose possessed 2.0 times protein to fucose by weight. The proteins in intact FSG were separated to two major (258 kDa and 237 kDa) and one minor (120 kDa) proteins by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) in the presence of 2-mercaptoethanol (2-ME) while the proteins could not be separated by HPLC in the presence of 0.1% SDS or SDS-PAGE without 2-ME. However, after carboxymethylation of FSG, two major (260 kDa and 240 kDa) proteins and two minor (140 kDa and 135 kDa) proteins were separated from the fucose sulfate moiety by HPLC in the presence of 0.1% SDS or SDS-PAGE without 2-ME. When FSG was first carboxymethylated with non-radioactive iodoacetic acid and then reduced with 2-ME and finally carboxymethylated with 14C-iodoacetic acid, the most of radioactivity was detected in 140 kDa and 135 kDa proteins. Carboxymethylted-FSG was less potent than intact FSG in induction of the acrosome reaction. Fucoidan, a fucose sulfate polymer, did not induce the acrosome reaction.  相似文献   
86.
Hydrophobic and charge-charge interactions of Salmonella typhimirium and Serratia marcescens were determined and related to their content of fimbriae and lipopolysaccharide (LPS). The cell surface structures were characterized with hydrophobic interaction chromatography (HIC), electrostatic interaction chromatography (ESIC) and particle electrophoresis measurements. The degree of interaction at the air-water interface was tested using a monolayered lipid film applied to an aqueous surface. The cell surface hydrophobicity of S. typhimurium in the presence of fimbriae was less in smooth than in rought bacteria. Examination of a series of rough mutants of S. typhimurium indicates that reduction of the O-side chain and core oligosaccharides was correlated with increased cell hydrophobicity. The enrichment factors at the air-water interface were significantly higher for fimbriated than for non-fimbriated S. typhimurium cells. Fimbriated S. marcescens cells were less hydrophobic and adhered to a lesser degree at the air-water surface than non-fimbriated counterparts. Electrophoretic measurements and adsorption to ion exchangers gives different information about the surface charge of bacteria. The latter technique gives the interaction between localized charged surfaces.Abbreviations HIC hydrophobic interaction chromatography - ESIC electrostatic interaction chromatography - LPS lipopolysaccharide - PBS phosphate buffered saline solution  相似文献   
87.
The antioxidative effect of α-tocopherol incorporated into lecithin liposomes was studied. Lipid peroxidation of liposome membranes, assayed as malondialdehyde production, was catalyzed by ascorbic acid and Fe2+. The peroxidation reaction, which did not involve the formation of singlet oxygen, superoxide, hydrogen peroxide, or a hydroxyl radical, was inhibited by α-tocopherol and a model compound of α-tocopherol, 2,2,5,7,8-pentamethyl-6-hydroxy-chroman (TMC), but not by phytol, α-tocopherylquinone, or α-tocopheryl acetate. One mole of α-tocopherol completely prevented peroxidation of about 100 moles of polyunsaturated fatty acid. Decrease in membrane fluidity by lipid peroxidation, estimated as increase of fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) embedded in the membrane, was also inhibited by α-tocopherol and TMC, reflecting their antioxidant functions. Cholesterol did not act as an antioxidant, even when incorporated in large amount into the liposome membranes, but it increased the antioxidative efficiency of α-tocopherol. When a mixture of liposomes with and without α-tocopherol was incubated with Fe2+ and ascorbic acid, α-tocopherol did not protect the liposomes not containing α-tocopherol from peroxidation. However, preincubation of the mixture, or addition of Triton X-100 allowed the α-tocopherol to prevent peroxidation of the liposomes not containing α-tocopherol. In contrast, in similar experiments, liposomes containing TMC prevented peroxidation of those without TMC without preincubation. Tocopherol in an amount so small as to exhibit only a slight antioxidative effect was oxidized when incorporated in egg lecithin liposomes, but it mostly remained unoxidized when incorporated in dipalmitoyllecithin liposomes, indicating that oxygen activated by ascorbic acid-Fe2+ does not oxidize α-tocopherol directly. Thus, decomposition of α-tocopherol may be caused by its interaction with peroxy and/or alkoxyl radicals generated in the process of lipid peroxidation catalyzed by Fe2+ and ascorbic acid.  相似文献   
88.
Injection of γ-carrageenin into t he pleural cavity of rats caused the accumulation of the pleural exudate. When levels of prostaglandins (PGs) and thromboxane (TX) B2 were quantified by gas chromatography-mass spectrometry as their methyl ester (ME)-dimethyllisopropylsilyl (DMiPS) ether or ME-methoxine-DMiPS ether derivatives, 6-keto-PGF reached the maximum at 1 hr after carrageenin, then PGE2 and TXB2 showed peaks at 3 hr and waned off before 9 hr. he PGF level was kept low, but PGD2, PGE1 and PGF were not detected. Aspirin (100 mg/kg, i.p.) significantly decreased the PG and TXB2 levels and suppressed the rate of plasma exudation until 5 hr, but did not at 7 hr, when it was measured by the amount of exuded pontamine sky blue injected intravenously. OKY-025 (300 mg/kg, i.p.), a selective TXA synthetase inhibitor, and tranylcypromine (20 mg/kg, i.p.), a PGI synthetase inhibitor, could not extensively inhibit the accumulation of the exudate. These results suggest that the cyclooxygenase products of arachidonic acid, particularly PGE2, definitely play an important role in the exudation during the first 5 hr.  相似文献   
89.
Summary Chemical polymerization of adenosine-5-phosphorimidazolide was conducted in the presence of oligouridylate templates. Oligo U with chain length more than eight served as a template and facilitated oligoadenylate formation. No template activity was observed when oligo U up to a hexamer was used. These results correlate with thermal transition temperatures of oligo U-pA complexes.  相似文献   
90.
Abstract: This paper describes a new, sensitive assay for dopamine-β-hydroxylase (DBH) activity in human cerebrospinal fluid (CSF), serum and brain tissues by high performance liquid chromatography (HPLC) with electrochemical detection (ED). Dopamine (DA) was used as a substrate and was incubated under optimal conditions. Norepinephrine (NE) formed enzymatically from DA was isolated by a double-column procedure, the first column of Dowex-50-H+ and the second column of aluminum oxide. NE was adsorbed on the second aluminum oxide column and then eluted with 0.5 M-hydrochloric acid and assayed by HPLC-ED. Epinephrine (EN) was added to each incubation mixture as an internal standard, and this assay was therefore highly reproducible. The peak height in HPLC was linear from 500 fmol to 100 pmol of NE and EN. The lower limit of detection for NE formed enzymatically was about 30 pmol, which indicated that the sensitivity of this procedure was comparable to that of radioassay procedures. We applied the method to measurement of the activity of and examination of some of the characteristics of DBH in human CSF. DBH activity in CSF of Parkinsonian patients was lower than that of control patients. The properties of DBH in human CSF were similar to those in serum and adrenal medulla.  相似文献   
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