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121.
In the Western World ischemic coronary disease is the leading cause of morbidity and mortality. Therapeutic approaches mostly aim to restore flow to a localized segment by angioplasty or bypass surgery. Therapeutic angiogenesis and or arteriogenesis describes a strategy where blood vessel formation is induced for the purposes of treating and/or preventing ischemic disease. At present, at least 17 clinical trials of myocardial angiogenesis have been presented involving over 900 patients. Therapeutic angiogenesis makes use of the administration of angiogenic growth factor protein or gene to promote the development of endogenous collateral vessels in ischemic myocardium. Most recently, interest has grown in the potential angiogenesis effects of cell therapy—such as autologous bone marrow cells or cultured stem cells—and there are now several groups initiating phase I/II trials in this area. (Mol Cell Biochem 264: 143–149, 2004)  相似文献   
122.
Clusterin has been implicated in lipid metabolism and atherogenesis, however, the influence of genetic variation has not been examined in Japanese. In this study, we identified 11 single nucleotide polymorphisms (SNPs) of clusterin gene by direct sequencing. Among them, one promoter SNP (-4453T>G), one missense SNP (4183G>A), and 2 common SNPs (5608T>C and 6316delT) were genotyped in 525 asymptomatic hypertensives not treated with lipid lowering agents. -4453T>G, 4183G>A, and 5608T>C showed no correlation with the clinical characteristics, however, in the 6316delT, an insertion (I)/deletion (D) polymorphism, D/D subjects had significantly higher levels of total cholesterol and low-density lipoprotein (LDL)-cholesterol than I/I subjects in females but not in males. Female subjects with the D allele (D/D+I/D) had greater intima-media thickness of the carotid artery than I/I subjects. In a multiple logistic regression analysis, the D allele of 6316delT was detected as an independent predictor for the plaque prevalence. In conclusion, the clusterin gene polymorphism may contribute to the serum lipid levels and the progression of carotid atherosclerosis in hypertensive Japanese females.  相似文献   
123.
Thrombopoietin (TPO) is the growth factor for megakaryocytes and platelets, however, it also acts as a potent regulator of stem cell proliferation. To examine the significance of TPO expression in proliferation of hepatic oval cells, the effect of adenovirus-mediated TPO gene transfer into livers of the Solt-Farber model, which mimics the condition where liver regeneration is impaired, was examined. Hepatic TPO mRNA peaked its expression at 2 days after gene transduction and then gradually decreased. The peripheral platelet number began to increase at 4 days (P<0.05) and reached its plateau at 9 days (P<0.01). Oval cells expressed c-Mpl, a receptor for TPO as well as immature hematopoietic and hepatocytic surface markers such as CD34 and AFP. The proliferating cell nuclear antigen-positive oval cells in rats into which adenovirus-TPO gene was transferred at 7 and 9 days were significantly greater than those in adenovirus-LacZ gene transferred (P<0.05, each), and the total numbers of oval cells in the adenovirus-TPO gene transferred at 9 and 13 days were also significantly greater than those in adenovirus-LacZ gene transferred (P<0.05, each). Expression of SCF protein was increased at 4, 7, and 9 days by TPO gene administration and that of c-Kit was increased at 4 and 7 days. These data suggest that adenovirus-mediated TPO gene transfer stimulated oval cell proliferation in liver as well as increasing peripheral platelet counts, emphasizing the significance of the TPO/c-Mpl system in proliferation of hepatic oval cells.  相似文献   
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Cryptochrome (CRY) is a blue-light-absorbing protein involved in the photic entrainment of the circadian clock in Drosophila melanogaster. We have investigated the locomotor activity rhythms of flies carrying cryb mutant and revealed that they have two separate circadian oscillators with different responsiveness to light. When kept in constant light conditions, wild-type flies became arrhythmic, while cryb mutant flies exhibited free-running rhythms with two rhythmic components, one with a shorter and the other with a longer free-running period. The rhythm dissociation was dependent on the light intensities: the higher the light intensities, the greater the proportion of animals exhibiting the two oscillations. External photoreceptors including the compound eyes and the ocelli are the likely photoreceptors for the rhythm dissociation, since rhythm dissociation was prevented in so1;cryb and norpAP41;cryb double mutant flies. Immunohistochemical analysis demonstrated that the PERIOD expression rhythms in ventrally located lateral neurons (LNvs) occurred synchronously with the shorter period component, while those in the dorsally located per-expressing neurons showed PER expression most likely related to the longer period component, in addition to that synchronized to the LNvs. These results suggest that the Drosophila locomotor rhythms are driven by two separate per-dependent clocks, responding differentially to constant light.  相似文献   
126.
To clarify the characteristics of thermophilic bacteria in cattle manure compost, enzymatic activity and species diversity of cultivated bacteria were investigated at 54, 60, 63, 66 and 70 degrees C, which were dependent on composting temperature. The highest level of thermophilic bacterial activity was observed at 54 degrees C. Following an increase in temperature to 63 degrees C, a reduction in bacterial diversity was observed. At 66 degrees C, bacterial diversity increased again, and diverse bacteria including Thermus spp. and thermophilic Bacillus spp. appeared to adapt to the higher temperature. At 70 degrees C, bacterial activity measured as superoxide dismutase and catalase activity was significantly higher than at 66 degrees C. However, the decomposition rate of protein in the compost was lower than the rate at 66 degrees C due to the higher compost temperature.  相似文献   
127.
We studied the phylogeny, population structure, and demographic history of Scolopsis taenioptera in the western Pacific Ocean. Using the 80 samples collected from four locations, we obtained the nucleotide sequences of mitochondrial cytochrome c oxidase subunit I and cytochrome b genes. We identified two distinct lineages showing a clear phylogeographic break that was possibly due to the Pleistocene sea-level change. One lineage was distributed in Iloilo (Philippines) and the other in Terengganu (Malaysia), Rayong (Thailand), and Ha Long Bay (Vietnam). The Terengganu and Rayong populations showed clear signs of demographic expansion; the Iloilo and Ha Long Bay populations were relatively stable or spatially expanded as geographically subdivided populations.  相似文献   
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129.
Bile alcohols in bile, urine, and feces of a patient with cerebrotendinous xanthomatosis have been analyzed by a combination of capillary gas-liquid chromatography and mass spectrometry after fractionation into groups according to mode of conjugation. The presence of at least 18 bile alcohols, which were excreted mainly as glucurono-conjugates in bile and urine, and as unconjugated forms in feces, was demonstrated. The following bile alcohols were identified with certainty by direct comparison with reference compounds: 5 beta-cholestane-3 alpha,7 alpha,12 alpha-triol; (23R)-5 beta-cholestane-3 alpha,7 alpha,12 alpha,23-tetrol; 5 alpha- and 5 beta-cholestane-3 alpha,7 alpha,12 alpha,24-tetrols; 5 alpha- and 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrols; 27-nor-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25-pentol; (22R)-5 beta-cholestane-3 alpha,7 alpha,12 alpha,22,25-pentol; (23R)- and (23S)-5 beta-cholestane-3 alpha,7 alpha, 12 alpha,23,25-pentols; 3 alpha,12 alpha,25-trihydroxy-5 beta-cholestane-7-one; (24R)- and (24S)-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,25-pentols; 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25,26-pentol. Although the bile alcohol profile in urine was quite different from those in bile and feces, the determination of urinary bile alcohols as well as of biliary and fecal bile alcohols could be used for diagnosis of cerebrotendinous xanthomatosis.  相似文献   
130.
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