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41.
Using a genome-wide single nucleotide polymorphism (SNP) panel, we observed population structure in a diverse group of Europeans and European Americans. Under a variety of conditions and tests, there is a consistent and reproducible distinction between “northern” and “southern” European population groups: most individual participants with southern European ancestry (Italian, Spanish, Portuguese, and Greek) have >85% membership in the “southern” population; and most northern, western, eastern, and central Europeans have >90% in the “northern” population group. Ashkenazi Jewish as well as Sephardic Jewish origin also showed >85% membership in the “southern” population, consistent with a later Mediterranean origin of these ethnic groups. Based on this work, we have developed a core set of informative SNP markers that can control for this partition in European population structure in a variety of clinical and genetic studies.  相似文献   
42.
Linoleic acid, and its hydroperoxides and secondary autoxidation products were orally administered to rats (400 mg/rat). Their effects on hepatic lipid metabolism were examined. Linoleic acid reduced the activities of de novo synthesis of fatty acids and acetyl-CoA carboxylase. It decreased the CoASH level and caused the accumulation of long-chain acyl-CoA. Hydroperoxides changed the compositions of unsaturated fatty acids in the hepatic lipids and lowered the content of neutral lipids. Secondary products stimulated carnitine palmitoyltransferase and decreased the content of neutral lipids. They reduced the activities of de novo synthesis of fatty acids and acetyl-CoA carboxylase, and the levels of CoASH and acetyl-CoA. Thus, the effect of secondary products was apparently different from those of linoleic acid and its hydroperoxides.  相似文献   
43.
We report the discovery of a novel benzylpiperidine derivative with serotonin transporter (SERT) inhibitory activity and 5-HT1A receptor weak partial agonistic activity showing the antidepressant-like effect. The 3-methoxyphenyl group and the phenethyl group of compound 1, which has weak SERT binding activity, but potent 5-HT1A binding activity, were optimized, leading to compound 35 with potent and balanced dual SERT and 5-HT1A binding activity, but also potent CYP2D6 inhibitory activity. Replacement of the methoxy group in the left part of compound 35 with a larger alkoxy group, such as ethoxy, isopropoxy or methoxy-ethoxy group ameliorated CYP2D6 inhibition, giving SMP-304 as a candidate. SMP-304 with serotonin uptake inhibitory activity and 5-HT1A weak partial agonistic activity, which could work as a 5-HT1A antagonist, displayed faster onset of antidepressant-like effect than a representative SSRI paroxetine in an animal model.  相似文献   
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This study has investigated the effect of a long period of overeating on the glycemic control and pancreatic beta-cell function in neonatally streptozocin treated impaired glucose tolerant mice. Neonatally streptozocin (60 mg/kg) treated male ICR mice with 150-200 mg/dl of fed blood glucose levels were divided into two groups at 6 weeks of age. One group was maintained on a cafeteria diet (SZC) and the other on ordinary mouse chow (SZ) until 30 weeks of age. Normal male ICR mice were divided into a cafeteria diet group (CC) and an ordinary chow group (Cont). SZC and CC consumed 134-124% of the caloric intake in SZ and Cont throughout the study. Marked elevation of the fed blood glucose level was observed and the glucose tolerance was progressively impaired in SZC. On pancreas perfusion at 30 weeks of age, insulin secretion to 30 mM glucose in SZC was significantly decreased compared with that in SZ. That in CC was slightly decreased compared with that in Cont. The pancreatic insulin concentration in SZC was significantly less than that in SZ. We conclude that chronic hyperglycemia, induced by the long period of overeating, accelerated the selective loss of beta-cell sensitivity to glucose. Even in normal mice that did not have marked hyperglycemia, insulin secretion to glucose was suppressed, probably by chronic stimulation of the beta-cell due to the long period of dietary excess.  相似文献   
46.
Trilobatin [4?-(β-D-glucopyranosyloxy)-2?,4”,6?-trihydroxydihydrochalcone] was synthesized from commercially available naringin in three steps with an overall yield of 30%. The key step was the acid-catalyzed site-selective hydrolysis of terminal α-rhamnopyranosidic linkage in neohesperidose involved in naringin under controlled conditions, by applying a high-pressure steam sterilizer.  相似文献   
47.
A non-dialyzable extract of fresh spinach leaves exhibited a strong antioxidant activity towards oxidation of linoleic acid and suppressed the melanin formation of a mouse melanoma cell line, B16 melanoma 4A5, without any significant effect on the proliferation of cells.  相似文献   
48.
To establish a non-radioactive, cell-free detection system for protein N-myristoylation, metabolic labeling in a cell-free protein synthesis system using bioorthogonal myristic acid analogues was performed. After Cu(I)-catalyzed azide–alkyne cycloaddition (CuAAC) with a biotin tag, the tagged proteins were separated by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) and blotted on a polyvinylidene fluoride (PVDF) membrane, and then protein N-myristoylation was detected by enhanced chemiluminescence (ECL) using horseradish peroxidase (HRP)-conjugated streptavidin. The results showed that metabolic labeling in an insect cell-free protein synthesis system using an azide analogue of myristic acid followed by CuAAC with alkynyl biotin was the most effective strategy for cell-free detection of protein N-myristoylation. To determine whether the newly developed detection method can be applied for the detection of novel N-myristoylated proteins from complementary DNA (cDNA) resources, four candidate cDNA clones were selected from a human cDNA resource and their susceptibility to protein N-myristoylation was evaluated using the newly developed strategy. As a result, the products of three cDNA clones were found to be novel N-myristoylated protein, and myristoylation-dependent specific intracellular localization was observed for two novel N-myristoylated proteins. Thus, the metabolic labeling in an insect cell-free protein synthesis system using bioorthogonal azide analogue of myristic acid was an effective strategy to identify novel N-myristoylated proteins from cDNA resources.  相似文献   
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The effectiveness of hybrid vigor, which can counteract deleterious effects of inbreeding in flightless Harmonia axyridis Pallas (Coleoptera: Coccinellidae), was investigated. First, we performed the reciprocal cross between two isofemale lines and compared survival and reproductive characteristics between isofemale and hybrid lines under laboratory conditions. The survival of one of the hybrid lines was significantly higher than that of the two isofemale lines. Early fecundity tended to be higher in the two hybrid lines than in the two isofemale lines. Second, we compared the effectiveness of control of Aphis gossypii Glover (Homoptera: Aphididae) between isofemale and hybrid lines by release experiments in greenhouses. The number of A. gossypii was suppressed in treatments in which two hybrid lines were released compared with those in which two isofemale lines were released. These results suggest that hybrid vigor is effective as a method for assuring the quality of flightless H. axyridis.  相似文献   
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