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71.
A total of 301 oocytes were recovered from crab-eating monkeys and subjected to insemination in vitro resulting in two fertilized ova. Sixteen monkeys in 24 cycles received 37.5 IU of hMG daily from the second day of the menstrual cycle for 7 to 10 days. Oocytes were recovered under laparotomy at 20 to 49 hr after administration of 1,000–1,500 IU of hCG. The maturation rate of the recovered oocytes was 24.2% as judged from morphological criteria under the light microscope. With additional maturation culture, the rate increased to 36.2%. The matured oocytes were inseminated at 3 to 4 hr after aspiration using homologous spermatozoa which had been capacitated in vitro. Two oocytes were judged as being fertilized based on the presence of 3 and 5 pronuclei, respectively, when examined 12 hr after the insemination. This is the first report of in vitro fertilized ova in nonhuman primates in Japan.  相似文献   
72.
When mature green tomato fruits are stored at 22?C for 30 days,they ripen normally and soften, but if they are kept at 33?Cfor 15 days (heat treatment), then stored at 22?C they do notsoften. The effect of heat treatment on the development of polygalacturonase(PG, EC 3.2.1.15 [EC] ) activities in tomato fruits during storagetherefore was studied. When mature green tomato fruits werestored at 22?C, PG activity, which had not been detectable inthe fruits, appeared as the color changed and increased dramaticallythereafter. PG activity, however, did not appear during heattreatment. When heat-treated fruits were transferred to 22?C,PG activity appeared after a 6-day lag period and increasedduring the next 30 days at 22?C to about 15% of the value detectedin ripe tomato fruits. The PG in ripe tomato fruits was composed of two isoenzymesthat had different mol wts. A high molecular form (PG-1, molwt 100K) appeared during the early stage of ripening and a lowmolecular form (PG-2, mol wt 44K) a little later. PG-2 increasedvigorously during ripening and eventually accounted for mostof the enzyme activity in the ripe fruits. Only a single isoenzyme(Y-PG, mol wt 100K), however, was detected in heat-treated tomatofruits stored at 22?C for 30 days. PG-1 and Y-PG gave the samemol wt on Sephacryl S-200 gel nitration, but could be separatedby Toyopearl HW-55 F gel filtration. (Received October 31, 1983; Accepted February 20, 1984)  相似文献   
73.
An extracellular amylase was obtained from a culture medium of Bacillus cereus NY-14. This enzyme was purified to show a single band on disc gel electrophoresis by ammonium sulfate fractionation and Sephadex G-100 gel filtration to 1101-fold of the activity of the original culture liquor. The purified enzyme had a molecular weight of 55,000, an isoelectric point of 6.13, an optimum pH of 6.0, and an optimum temperature of 55°C. The pH-stability range was wide; the enzyme retained more than 80% of its initial activity in the range of pH 5.5 to 12. It was stable below 35°C and required calcium ions for the stabilization. The action pattern of this enzyme on amylaceous polysaccharides was unique in that the predominant product was maltopentaose. The purified amylase could also digest starch granules of such plants as rice, barley, corn, and kuzu to produce maltopentaose as the main product.  相似文献   
74.
Histamine is a potent mediator in allergic inflammatory processes and is released by basophils and mast cells. The aim of this study was to investigate the effect of histamine on in vitro migration of human fetal lung fibroblasts (HFL-1) to human plasma fibronectin (HFn), a chemoattractant. Using the blindwell chamber technique, histamine alone had no chemotactic activity. However, histamine augmented HFn-induced HFL-1 migration at concentrations ranging between 0 and 10?7 M (290.6 ± 20.8%) (P < 0.05). The concentration-response was bell-shaped. The effect of histamine increased with time. The stimulatory effect of histamine on HFL-1 migration was inhibited by an H4 receptor antagonist, JNJ7777120 (10?5 M). Histamine’s effect was also inhibited by pertussis toxin (50 ng/ml), showing that the effect was mediated by the H4 receptor. This study demonstrated that histamine has the potential to stimulate human lung fibroblast migration, and thus may contribute to regulation of wound healing and the development of fibrotic disorders of the lung.  相似文献   
75.
Amyloid-β peptide (Aβ), which is generated by the β- and γ-secretase-mediated proteolysis of β-amyloid precursor protein (APP), plays an important role in the pathogenesis of Alzheimer's disease (AD). We recently reported that prostaglandin E(2) (PGE(2) ) stimulates the production of Aβ through both EP(2) and EP(4) receptors and that activation of the EP(4) receptor stimulates Aβ production through endocytosis and activation of γ-secretase. We here found that transgenic mice expressing mutant APP (APP23) mice showed a greater or lesser apparent cognitive deficit when they were crossed with mice lacking EP(2) or EP(4) receptors, respectively. Mice lacking the EP(4) receptor also displayed lower levels of Aβ plaque deposition and less neuronal and synaptic loss than control mice. Oral administration of a specific EP(4) receptor antagonist, AE3-208 to APP23 mice, improved their cognitive performance, as well as decreasing brain levels of Aβ and suppressing endocytosis and activation of γ-secretase. Taken together, these results suggest that inhibition of the EP(4) receptor improves the cognitive function of APP23 mice by suppressing Aβ production and reducing neuronal and synaptic loss. We therefore propose that EP(4) receptor antagonists, such as AE3-208, could be therapeutically beneficial for the prevention and treatment of AD.  相似文献   
76.
S1P(3)-sparing S1P(1) agonists have attracted attention as a suppressant of autoimmunity with reduced side effects. Our synthetic efforts and extensive SAR studies led to the discovery of 10b named CS-2100 with the EC(50) value of 4.0 nM for human S1P(1) and over 5000-fold selectivity against S1P(3). The in vivo immunosuppressive efficacy was evaluated in rats on host versus graft reaction and the ID(50) value was determined at 0.407mg/kg. The docking studies of CS-2100 with the homology model of S1P(1) and S1P(3) showed that the ethyl group on the thiophene ring of CS-2100 was sterically hindered by Phe263 in S1P(3), not in the case of Leu276 in S1P(1). This observation gives an explanation for the excellent S1P(3)-sparing characteristic of CS-2100.  相似文献   
77.
Introduction of the 2,2-dimethyl-4-phenylpiperazin-5-one scaffold into the P(3)-P(1) portion of the (2S,4S,5S)-5-amino-6-dialkylamino-4-hydroxy-2-isopropylhexanamide backbone dramatically increased the renin inhibitory activity without using the interaction to the S(3)(sp) pocket. Compound 31 exhibited >10,000-fold selectivity over other human proteases, and 18.5% oral bioavailability in monkey.  相似文献   
78.
Utilizing X-ray crystal structure analysis, (3S,5R)-5-[4-(2-chlorophenyl)-2,2-dimethyl-5-oxopiperazin-1-yl]piperidine-3-carboxamides were designed and identified as renin inhibitors. The most potent compound 15 demonstrated favorable pharmacokinetic and pharmacodynamic profiles in rat.  相似文献   
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