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151.
152.
AimsWe investigated the effect of globin digest (GD) on the liver injury and hepatic gene expression profile in galactosamine (GalN)-induced liver injury.Main methodsThe effect of GD on the liver injury was examined by measuring the activities of serum transferases and hepatic antioxidant enzymes, histopathological analysis, gene expression profile, and proteins of the peroxisome proliferator-activated receptor alpha (PPARα) and met proto-oncogene (c-Met) in SD rats at 24 h after GalN administration. The effect of GD on the expression of PPARα and its target gene in AML-12 mouse hepatocytes was also examined.Key findingsGD suppressed the elevated activities of serum transferases in GalN-induced liver injury in SD rats. The thiobarbituric acid reactive substance content in GalN-injured liver was a decreasing tendency by GD. GD suppressed the increased oxidized glutathione content, and increased the decreased protein, reduced glutathione contents, and catalase activity in GalN-injured liver. GD may improve the antioxidant defense system and protein synthesis in GalN-injured liver. GD suppressed the elevated expression of the genes related to the inflammation, and decreased the histopathological grade value of inflammatory cell infiltration in GalN-injured liver. GD increased the expression of PPARα protein in GalN-injured liver, and also increased the expression of PPARα and its target gene in AML-12 hepatocytes. The total and phosphorylated c-Met proteins in GalN-injured liver were the increasing tendencies by GD.SignificanceThese findings indicate that GD has the hepatoprotective effect on GalN-induced liver injury in SD rats.  相似文献   
153.
Chromosomal mapping of the butterfly lizards Leiolepis belliana belliana and L. boehmei was done using the 18S-28S and 5S rRNA genes and telomeric (TTAGGG)n sequences. The karyotype of L. b. belliana was 2n = 36, whereas that of L. boehmei was 2n = 34. The 18S-28S rRNA genes were located at the secondary constriction of the long arm of chromosome 1, while the 5S rRNA genes were found in the pericentromeric region of chromosome 6 in both species. Hybridization signals for the (TTAGGG)n sequence were observed at the telomeric ends of all chromosomes, as well as interstitially at the same position as the 18S-28S rRNA genes in L. boehmei. This finding suggests that in L. boehmei telomere-to-telomere fusion probably occurred between chromosome 1 and a microchromosome where the 18S-28S rRNA genes were located or, alternatively, at the secondary constriction of chromosome 1. The absence of telomeric sequence signals in chromosome 1 of L. b. belliana suggested that its chromosomes may have only a few copies of the (TTAGGG)n sequence or that there may have been a gradual loss of the repeat sequences during chromosomal evolution.  相似文献   
154.
Stearoyl-coenzyme A desaturase 1 (SCD1) is the rate-limiting enzyme in the synthesis of monounsaturated fatty acids. However, the impact of SCD1 on atherosclerosis remains unclear. The aim of this study was to determine whether SCD1 affects macrophage reverse cholesterol transport (RCT) in mice. Compared to the control, adenoviral-mediated SCD1 overexpression in RAW264.7 macrophages increased cholesterol efflux to HDL, but not to apoA-I, without clear changes in ABCA1, ABCG1 and SR-BI expressions. While knockdown of ABCG1 and SR-BI did not affect the SCD1-induced cholesterol efflux to HDL, SCD1-overexpressing macrophages promoted the formation of both normal- and large-sized HDL in media, accompanying increased apolipoprotein A-I levels in HDL fractions. Transformation to larger particles of HDL was independently confirmed by nuclear magnetic resonance-based lipoprotein analysis. Interestingly, media transfer assays revealed that HDL generated by SCD1 had enhanced cholesterol efflux potential, indicating that SCD1 transformed HDL to a more anti-atherogenic phenotype. To study macrophage RCT in vivo, 3H-cholesterol-labeled RAW264.7 cells overexpressing SCD1 or the control were intraperitoneally injected into mice. Supporting the in vitro data, injection of SCD1-macrophages resulted in significant increases in 3H-tracer in plasma, liver, and feces compared to the control. Moreover, there was a shift towards larger particles in the 3H-tracer distribution of HDL fractions obtained from the mice.  相似文献   
155.
Adult T-cell leukemia/lymphoma (ATL) is a fatal malignancy caused by infection with human T-lymphotropic virus type-1 and there is no accepted curative therapy for ATL. We searched for biological active substances for the prevention and treatment of ATL from several species of herbs. The ATL cell growth-inhibitory activity and apoptosis assay showed that carnosol, which is an ingredient contained in rosemary (Rosmarinus officinalis), induced apoptosis in ATL cells. Next, to investigate the apoptosis-inducing mechanism of carnosol, we applied proteomic analysis using fluorescent two-dimensional differential gel electrophoresis and mass spectrometry. The proteomic analysis showed that the expression of reductases, enzymes in glycolytic pathway, and enzymes in pentose phosphate pathway was increased in carnosol-treated cells, compared with untreated cells. These results suggested that carnosol affected the redox status in the cells. Further, the quantitative analysis of glutathione, which plays the central role for the maintenance of intracellular redox status, indicated that carnosol caused the decrease of glutathione in the cells. Further, N-acetyl-l-cystein, which is precursor of glutathione, canceled the efficiency of carnosol. From these results, it was suggested that the apoptosis-inducing activity of carnosol in ATL cells was caused by the depletion of glutathione.  相似文献   
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157.
When compared with other epithelial ovarian cancers, the clinical characteristics of ovarian clear cell adenocarcinoma (CCC) include 1) a higher incidence among Japanese, 2) an association with endometriosis, 3) poor prognosis in advanced stages, and 4) a higher incidence of thrombosis as a complication. We used high resolution comparative genomic hybridization (CGH) to identify somatic copy number alterations (SCNAs) associated with each of these clinical characteristics of CCC. The Human Genome CGH 244A Oligo Microarray was used to examine 144 samples obtained from 120 Japanese, 15 Korean, and nine German patients with CCC. The entire 8q chromosome (minimum corrected p-value: q = 0.0001) and chromosome 20q13.2 including the ZNF217 locus (q = 0.0078) were amplified significantly more in Japanese than in Korean or German samples. This copy number amplification of the ZNF217 gene was confirmed by quantitative real-time polymerase chain reaction (Q-PCR). ZNF217 RNA levels were also higher in Japanese tumor samples than in non-Japanese samples (P = 0.027). Moreover, endometriosis was associated with amplification of EGFR gene (q = 0.047), which was again confirmed by Q-PCR and correlated with EGFR RNA expression. However, no SCNAs were significantly associated with prognosis or thrombosis. These results indicated that there may be an association between CCC and ZNF217 amplification among Japanese patients as well as between endometriosis and EGFR gene amplifications.  相似文献   
158.
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160.
The antinociceptive effect of Tyr-d-Arg-Phe-Sar (TAPS) at the spinal level was characterized with the mouse tail-flick test. Intrathecal (i.t.) administration of TAPS produced a dose-dependent antinociception. The antinociception induced by TAPS was completely blocked by i.t. pretreatment with the mu-opioid receptor antagonist beta-funaltrexamine, the mu(1)-opioid receptor antagonist naloxonazine or the kappa-opioid receptor antagonist nor-binaltorphimine, but not with the delta-opioid receptor antagonist naltrindole. Moreover, TAPS-induced antinociception was dose-dependently attenuated by i.t. pretreatment with an antiserum against dynorphin B, but not against dynorphin A, alpha-neo-endorphin, [Met(5)]enkephalin, or [Leu(5)]enkephalin. In mice lacking prodynorphin, TAPS-induced antinociception was significantly reduced compared to that in wild-type mice. These results suggest that TAPS mainly stimulates mu(1)-opioid receptors, which subsequently induce the release of dynorphin B, which then acts on kappa-opioid receptors to produce antinociception.  相似文献   
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