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991.
Genetic variations at urotensin II and urotensin II receptor genes and risk of type 2 diabetes mellitus in Japanese 总被引:1,自引:0,他引:1
Suzuki S Wenyi Z Hirai M Hinokio Y Suzuki C Yamada T Yoshizumi S Suzuki M Tanizawa Y Matsutani A Oka Y 《Peptides》2004,25(10):1803-1808
Urotensin II is among the most potent vasoactive hormones known and the urotensin II (UTS2) gene is localized to 1p36-p32, one of the regions reported to show possible linkage with type 2 diabetes in Japanese. When we surveyed genetic polymorphisms in the UTS2 and urotensin II receptor (GPR14) gene, we identified two SNPs with amino acid substitutions (designated T21M and S89N and an SNP in the promotor region (-605G>A) of the UTS2 gene, and two SNPs in the non-coding region of the GPR14 gene. We then studied these three SNPs in the UTS2 gene and two SNPs in the GPR14 gene in 152 Japanese subjects with type 2 diabetes mellitus and two control Japanese populations. The allele frequency of 89N was significantly higher in type 2 diabetic patients than in both elderly normal subjects (P = 0.0018) and subjects with normal glucose tolerance (P = 0.0011), whereas the allele frequency of T21M and -605G>A in the UTS2 gene and those of two SNPs in the GPR14 gene were essentially identical in these three groups. Furthermore, in the subjects with normal glucose tolerance, 89N was associated with significantly higher insulin levels on oral glucose tolerance test, suggesting reduced insulin sensitivity in subjects with 89N. These results strongly suggest that subjects with S89N in the UTS2 gene are more insulin-resistant and thus more susceptible to type 2 diabetes mellitus development. 相似文献
992.
993.
When methane (CH(4)) and O(2) are present, nitrogen can be removed from wastewater that does not contain other organic carbon sources. In this study, microbial activities during methane-dependent denitrification (MDD) were investigated by adding inhibitors of methane-oxidation and denitrification. Sludge susceptible to MDD showed methane oxidation activity in the presence of CH(4) and O(2), and denitrification activity with methanol and acetate under anoxic conditions. Methyl fluoride (CH(3)F) is known to inhibit methane oxidation. When CH(3)F was present, MDD did not occur, perhaps because methane oxidation was inhibited. Tungstate (WO(4)(2-)), a known inhibitor of nitrate reduction, also lowered denitrification activity in the sludge, and partly inhibited methane oxidation. When WO(4)(2-) was added to the medium, MDD almost ceased, perhaps because of a synergic inhibitory effect on denitrification and methane oxidation. These results show that both methane oxidation and denitrification contribute to MDD. 相似文献
994.
Tanitame A Oyamada Y Ofuji K Kyoya Y Suzuki K Ito H Kawasaki M Nagai K Wachi M Yamagishi J 《Bioorganic & medicinal chemistry letters》2004,14(11):2857-2862
In this study, we report the design, synthesis and structure-activity relationships of novel indazole derivatives as DNA gyrase inhibitors with Gram-positive antibacterial activity. Our results show that selected compounds from this series exhibit potent antibacterial activity against Gram-positive bacteria including multi-drug resistant strains that is methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecalis (VRE). 相似文献
995.
Laxmi YR Suzuki N Kim SY Shibutani S 《Bioorganic & medicinal chemistry letters》2004,14(15):4051-4054
A phosphoramidite chemical synthesis of oligodeoxynucleotides containing a diastereoisomer of (E)-alpha-(N(2)-deoxyguanosinyl)-N-desmethyltamoxifen, a major tamoxifen (TAM)-derived DNA adduct in animal and women treated with TAM, was described. The site-specifically modified oligodeoxynucleotide can be used for mutagenesis, DNA repair, and 3D structural studies and also as standard for quantitative analysis of TAM-DNA adducts in animal and human. 相似文献
996.
Shimazawa R Suzuki T Dodo K Shirai R 《Bioorganic & medicinal chemistry letters》2004,14(12):3291-3294
Potent dysidiolide analogs were synthesized by structural hybridization of dysidiolide and vitamin D(3). These analogs exhibited strong inhibitory activity toward dual-specificity phosphatase Cdc25A (IC(50)=0.44-0.89 microM). 相似文献
997.
998.
Tsukamoto H Hishinuma T Suzuki N Tayama R Hiratsuka M Yoshihisa T Mizugaki M Goto J 《Prostaglandins & other lipid mediators》2004,73(3-4):191-213
Thiazolidinedione, peroxisome proliferator-activated receptor gamma (PPARgamma) agonist, has been used as an anti-diabetic drug and as an useful tool to elucidate multiple PPARgamma functions by in vitro and in vivo studies. We investigated the effects of thiazolidinediones on prostanoid production in lipopolysaccharide-stimulated cells. The high concentrations (>10 microM) of rosiglitazone and pioglitazone significantly increased lipopolysaccharide-stimulated prostanoid production such as thromboxane A2 and prostaglandin E2. However, PPARgamma antagonist could not inhibit them. In PPARgamma-deficient cells, thiazolidinediones increased prostaglandin E2 production. Thiazolidinediones increased arachidonic acid (AA) release from the cell membrane by not stimulating AA releasing process involving several phospholipase A2s but inhibiting AA reuptaking process. The expression of cyclooxygenase-1 and cyclooxygenase-2 were not affected by thiazolidinediones. In this study, we demonstrated that high concentrations of TZDs increased AA release by the inhibition of AA reuptaking process, leading to subsequent increase in the prostanoid production in a PPARgamma-independent manner. This mechanism provides useful information for the elucidation of multiple PPARgamma functions and diabetic drug therapy. 相似文献
999.
1000.
Genetic and geographical differentiation of <Emphasis Type="Italic">Pandaka</Emphasis> gobies in Japan 总被引:1,自引:1,他引:0
Takahiko?MukaiEmail author Toshiyuki?Suzuki Mutsumi?Nishida 《Ichthyological Research》2004,51(3):222-227
The mitochondrial DNA (mtDNA) phylogeny of Japanese Pandaka species (Perciformes: Gobiidae) was inferred from partial nucleotide sequences of the mitochondrial 12S and 16S rRNA genes (1083bp). The resultant mtDNA tree showed two major clades (clade I and clade II), which were inconsistent with the present taxonomic classification. One of the major clades was further divided into two geographical groups, distributed on the Japanese Major Islands (clade I-A) and from Amami-oshima Island to Iriomote Island (clade I-B). The mtDNA haplotypes in clade II were found only on Iriomote Island. The mtDNA divergences in clade I indicated that the Japanese Major Island (clade I-A) and Ryukyu (clade I-B) groups have been geographically isolated from each other for millions of years, based on the putative molecular divergence rate. The geographical distributions of mtDNA haplotypes in clade I-A and clade I-B also suggested that Pandaka gobies had not dispersed to distant offshore islands, indicating that their geographical differentiation may be closely associated with the geological history of the Japanese and Ryukyu Archipelagos.This revised version was published online in January 2005 with corrections to the repetition of the 1st authors name. 相似文献