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排序方式: 共有884条查询结果,搜索用时 31 毫秒
81.
Li Z Mizuno S Nakamura T 《American journal of physiology. Gastrointestinal and liver physiology》2007,292(2):G639-G646
Cholestasis, an impairment of bile outflux, frequently occurs in liver diseases. In this process, an overaccumulation of bile acids causes hepatocyte necrosis and apoptosis, leading to advanced hepatitis. Hepatocyte growth factor (HGF) is mitogenic toward hepatocytes, but it is still unclear whether HGF has physiological and therapeutic functions during the progression of cholestasis. Using anti-HGF IgG or recombinant HGF in mice that had undergone bile duct ligation (BDL), we investigated the involvement of HGF in cholestasis-induced hepatitis. After the BDL surgery, HGF and c-Met mRNA levels transiently increased in livers during the progression of cholestatic hepatitis. When c-Met tyrosine phosphorylation was blocked in the livers of BDL-treated mice by anti-HGF IgG, hepatic dysfunction became evident, associated with the acceleration of hepatocyte necrosis and apoptosis. Inversely, administration of recombinant HGF into the mice led to the prevention of cholestasis-induced inflammation: HGF suppressed the hepatic expression of intracellular adhesion molecule-1 and neutrophil infiltration in BDL-treated mice. As a result, parenchymal necrosis was suppressed in the HGF-injected BDL mice. In addition, HGF supplement therapy reduced the number of apoptotic hepatocytes in cholestatic mice, associated with the early induction of Bcl-xL. The administration of HGF enhanced hepatic repair, via accelerating G1/S progression in hepatocytes. Our study showed that 1) upregulation of HGF production is required for protective mechanisms against cholestatic hepatitis and 2) enhancement of the intrinsic defense system by adding HGF may be a reasonable strategy to attenuate hepatic inflammation, necrosis, and apoptosis under bile-congestive conditions. 相似文献
82.
We examined the influences of regular sexual activity and marital status on salivary testosterone levels in healthy adult
Japanese men. Forty-four men (20–66 years) collected their saliva thrice a day (0900–1000, 1300–1400, and 1700–1800). The
testosterone levels at each collection time negatively correlated with the ages of the participants; therefore, residual testosterone
levels were used for analyses after correcting for age by linear regression. The testosterone-lowering effect of marriage
was marginal and the regular sexual activity more strongly associated with lower testosterone levels in morning saliva. The
possible neurofeedback systems underlying the phenomenon are discussed. 相似文献
83.
Furuhata S Ando K Oki M Aoki K Ohnishi S Aoyagi K Sasaki H Sakamoto H Yoshida T Ohnami S 《Molecular and cellular biochemistry》2007,298(1-2):125-138
Among the many tissue stem or progenitor cells recently being unveiled, endothelial progenitor cells (EPCs) have attracted
particular attention, not only because of their cardinal role in vascular biology and embryology but also because of their
potential use in the therapeutic development of a variety of postnatal diseases, including cardiovascular and peripheral vascular
disorders and cancer. The aim of this study is to provide some basic and comprehensive information on gene expression of EPCs
to characterize the cells in molecular terms. Here, we focus on EPCs derived from CD34-positive mononuclear cells of human
umbilical cord blood. The EPCs were purified and expanded in culture and analyzed by a high-density oligonucleotide microarray
and real-time RT-PCR analysis. We identified 169 up-regulated and 107 down-regulated genes in the EPCs compared with three
differentiated endothelial cells of human umbilical vein endothelial cells (HUVEC), human lung microvascular endothelial cells
(LMEC) and human aortic endothelial cells (AoEC). It is expected that the obtained list include key genes which are critical
for EPC function and survival and thus potential targets of EPC recognition in vivo and therapeutic modulation of vasculogenesis
in cancer as well as other diseases, in which de novo vasculogenesis plays a crucial role. For instance, the list includes
Syk and galectin-3, which encode protein tyrosine kinase and β-galactoside-binding protein, respectively, and are expressed higher in EPCs than
the three control endothelial cells. In situ hybridization showed that the genes were expressed in isolated cells in the fetal
liver at E11.5 and E14.5 of mouse development. 相似文献
84.
Shiina I Sano Y Nakata K Suzuki M Yokoyama T Sasaki A Orikasa T Miyamoto T Ikekita M Nagahara Y Hasome Y 《Bioorganic & medicinal chemistry》2007,15(24):7599-7617
Two new synthetic pathways to the anti-cancer agent tamoxifen and its derivatives were developed. The first route involved the aldol reaction of benzyl phenyl ketone with acetaldehyde followed by Friedel–Crafts substitution with anisole in the presence of Cl2Si(OTf)2 to produce 1,1,2-triaryl-3-acetoxybutane, a precursor of the tamoxifen derivatives. The second one utilized the novel three-component coupling reaction among aromatic aldehydes, cinnamyltrimethylsilane, and aromatic nucleophiles using HfCl4 as a Lewis acid catalyst to produce 3,4,4-triarylbutene, that is also a valuable intermediate of the tamoxifen derivatives. The former strategy requires a total of 10 steps from the aldol formation to the final conversion to tamoxifen, whereas the latter needs only three or four steps to produce tamoxifen and droloxifene including the installation of the side-chain moiety and the base-induced double-bond migration to form the tetra-substituted olefin structure. This synthetic strategy seems to serve as a new and practical pathway to prepare not only the tamoxifen derivatives but also the other SERMs (selective estrogen receptor modulators) including estrogen-dependent breast cancer and osteoporosis agents. 相似文献
85.
Aoi W Naito Y Nakamura T Akagiri S Masuyama A Takano T Mizushima K Yoshikawa T 《The Journal of nutritional biochemistry》2007,18(2):140-145
Milk fermented with a starter containing Lactobacillus helveticus and Saccharomyces cerevisiae is drunk on a daily basis by many people in Japan and has several beneficial effects. We studied the influence of this fermented milk product on muscle damage after prolonged exercise in rats. Wistar rats were divided into four groups: rested controls, rested rats given fermented milk diet, exercised rats and exercised rats given fermented milk diet. After 3 weeks of acclimatization, both exercise groups were made to run on a treadmill at 26 m/min for 60 min. Exercise increased the serum creatine kinase level, as well as myeloperoxidase activity and the level of thiobarbituric-acid-reactive substances in the gastrocnemius muscle after 24 h. These changes were ameliorated by intake of fermented milk. An increase of CINC-1 was also ameliorated by fermented milk. Furthermore, milk diet increased the mRNA and protein levels of protective proteins such as antioxidants and chaperone proteins. These results indicate that fermented milk can ameliorate delayed-onset muscle damage after prolonged exercise, which is associated with an increased antioxidant capacity of muscles. 相似文献
86.
Epigenetic field for cancerization 总被引:2,自引:0,他引:2
Ushijima T 《Journal of biochemistry and molecular biology》2007,40(2):142-150
87.
We designed and synthesized a Py-Im polyamide seco-CBI conjugate protected by a photocleavable group and demonstrated that it was selectively activated by UV irradiation both in vitro and in vivo. Sequence-specific alkylating Py-Im polyamides containing photolabile linkers may be useful for developing novel chemical- or enzyme-activated anticancer agents and may facilitate spatiotemporal control of gene expression. 相似文献
88.
Sugimoto T Horaguchi K Shoji H 《Journal of industrial microbiology & biotechnology》2011,38(12):1985-1991
Submerged batch cultures of Aspergillus kawachii grown on indigestible dextrin were investigated for potential improvements in glucoamylase (GA) production. In flask culture,
specific GA productivities per dry weight biomass using dextrin and indigestible dextrin were 11.0 and 56.1 mU/mg-DW, respectively.
Indigestible dextrin was a poor substrate for enzymatic hydrolysis. Rates of glucose formation from dextrin and indigestible
dextrin by enzymatic hydrolysis were 0.477 and 0.100 mg-glucose/ml/h, respectively. For this reason, residual glucose concentrations
in batch cultures grown on indigestible dextrin remained below 1.32 mg/ml where glucose-limiting conditions were easily maintained.
Batch culture using indigestible dextrin had the same residual glucose profile as dextrin fed-batch culture, and nearly the
same GA activity was obtained after 42.5 h of growth. However, between 42.5 and 66 h, the GA production rate of the indigestible
dextrin batch culture (11.5 mU/ml/h) was higher than that of the dextrin fed-batch culture (6.5 mU/ml/h). During this period,
a high amount of residual maltooligosaccharide was detected in the culture supernatant grown on indigestible dextrin. The
high GA productivity observed in the indigestible dextrin batch culture may have resulted from the absence of glucose and
the simultaneous presence of maltooligosaccharides throughout growth. 相似文献
89.
RUNX3 suppresses gastric epithelial cell growth by inducing p21(WAF1/Cip1) expression in cooperation with transforming growth factor {beta}-activated SMAD 总被引:3,自引:0,他引:3 下载免费PDF全文
Chi XZ Yang JO Lee KY Ito K Sakakura C Li QL Kim HR Cha EJ Lee YH Kaneda A Ushijima T Kim WJ Ito Y Bae SC 《Molecular and cellular biology》2005,25(18):8097-8107
90.
DNA is an attractive memory unit because of its immense information density. Here, we describe a memory model made of DNA, called Nested Primer Molecular Memory (NPMM). NPMM consists of many DNA strands, and each DNA strand consists of two areas: a data area and a data address area. When the address of target data is specified, only the target data can be extracted from NPMM. In this paper, we evaluate the validity of the basic operations of NPMM and then discuss the feasibility of scaled-up NPMM through some laboratory experiments. In the latter, we deal with scaled-up NPMM simulated by the Concentration Scaling method. 相似文献