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971.
972.
Suzuki T Matsuura A Kouketsu A Hisakawa S Nakagawa H Miyata N 《Bioorganic & medicinal chemistry》2005,13(13):4332-4342
A series of suberoylanilide hydroxamic acid (SAHA)-based non-hydroxamates was designed, synthesized, and evaluated for their histone deacetylase (HDAC) inhibitory activity. Among these, methyl sulfoxide 15 inhibited HDACs in enzyme assays and caused hyperacetylation of histone H4 while not inducing the accumulation of acetylated alpha-tubulin in HCT116 cells. 相似文献
973.
Tatsuya Maruhashi Kensuke Noma Yumiko Iwamoto Akimichi Iwamoto Nozomu Oda Masato Kajikawa Takeshi Matsumoto Takayuki Hidaka Yasuki Kihara Kazuaki Chayama Ayumu Nakashima Chikara Goto James K. Liao Yukihito Higashi 《PloS one》2014,9(10)
Objective
Rho-associated kinase (ROCK) signaling pathway has been shown to mediate various cellular functions including cell proliferation, migration, adhesion, apoptosis, and contraction, all of which may be involved in pathogenesis of atherosclerosis. Endogenous nitric oxide (NO) is well known to have an anti-atherosclerotic effect, whereas the exogenous NO-mediated cardiovascular effect still remains controversial. The purpose of this study was to evaluate the effect of exogenous NO on ROCK activity in vascular smooth muscle cells (VSMCs) in vitro and in vivo.Methods
VSMCs migration was evaluated using a modified Boyden chamber assay. ROCK activities were measured by Western blot analysis in murine and human VSMCs and aorta of mice treated with or without angiotensin II (Ang II) and/or sodium nitroprusside (SNP), an NO donor.Results
Co-treatment with SNP inhibited the Ang II-induced cell migration and increases in ROCK activity in murine and human VSMCs. Similarly, the increased ROCK activity 2 weeks after Ang II infusion in the mouse aorta was substantially inhibited by subcutaneous injection of SNP.Conclusions
These findings suggest that administration of exogenous NO can inhibit ROCK activity in VSMCs in vitro and in vivo. 相似文献974.
Yada T Shimokawa H Hiramatsu O Haruna Y Morita Y Kashihara N Shinozaki Y Mori H Goto M Ogasawara Y Kajiya F 《American journal of physiology. Heart and circulatory physiology》2006,291(3):H1138-H1146
We have recently demonstrated that endogenous H2O2 plays an important role in coronary autoregulation in vivo. However, the role of H2O2 during coronary ischemia-reperfusion (I/R) injury remains to be examined. In this study, we examined whether endogenous H2O2 also plays a protective role in coronary I/R injury in dogs in vivo. Canine subepicardial small coronary arteries (>or=100 microm) and arterioles (<100 microm) were continuously observed by an intravital microscope during coronary I/R (90/60 min) under cyclooxygenase blockade (n=50). Coronary vascular responses to endothelium-dependent vasodilators (ACh) were examined before and after I/R under the following seven conditions: control, nitric oxide (NO) synthase (NOS) inhibitor NG-monomethyl-L-arginine (L-NMMA), catalase (a decomposer of H2O2), 8-sulfophenyltheophylline (8-SPT, an adenosine receptor blocker), L-NMMA+catalase, L-NMMA+tetraethylammonium (TEA, an inhibitor of large-conductance Ca2+-sensitive potassium channels), and L-NMMA+catalase+8-SPT. Coronary I/R significantly impaired the coronary vasodilatation to ACh in both sized arteries (both P<0.01); L-NMMA reduced the small arterial vasodilatation (both P<0.01), whereas it increased (P<0.05) the ACh-induced coronary arteriolar vasodilatation associated with fluorescent H2O2 production after I/R. Catalase increased the small arterial vasodilatation (P<0.01) associated with fluorescent NO production and increased endothelial NOS expression, whereas it decreased the arteriolar response after I/R (P<0.01). L-NMMA+catalase, L-NMMA+TEA, or L-NMMA+catalase+8-SPT further decreased the coronary vasodilatation in both sized arteries (both, P<0.01). L-NMMA+catalase, L-NMMA+TEA, and L-NMMA+catalase+8-SPT significantly increased myocardial infarct area compared with the other four groups (control, L-NMMA, catalase, and 8-SPT; all, P<0.01). These results indicate that endogenous H2O2, in cooperation with NO, plays an important cardioprotective role in coronary I/R injury in vivo. 相似文献
975.
Precise measurements of the partial pressure of CO2 (PCO2) in oceanic and lagoonal surface waters from Palau Barrier Reef and Majuro Atoll were taken to ascertain the net effect of
these coral reef systems on air-sea CO2 exchange. PCO2 in the surface water in the lagoon of Palau Barrier Reef and Majuro Atoll was 48 and 14 μatm higher than in the surrounding
oceanic water, respectively. A total carbon dioxide vs. total alkalinity diagram indicates that calcification is mainly responsible
for CO2 evasion in these coral reef systems.
Accepted: 31 March 1997 相似文献
976.
The endotoxins from two recently-classified subspecies of Fusobacterium, namely F. necrophorum subsp. necrophorum and F. necrophorum subsp. funduliforme, were compared. Chemical analysis of the isolated endotoxins revealed that they were clearly different. Distinct levels of polysaccharides were demonstrated. The endotoxins isolated were devoid of heptose and 3-deoxy-D-manno-octulosonate (KDO). The endotoxins of F. n. necrophorum and F. n. funduliforme contained lipid A in a ratio of 4:1 which may account for the variations in their virulence. 相似文献
977.
Localization of a gene for benign adult familial myoclonic epilepsy to chromosome 8q23.3-q24.1. 下载免费PDF全文
M Mikami T Yasuda A Terao M Nakamura S Ueno H Tanabe T Tanaka T Onuma Y Goto S Kaneko A Sano 《American journal of human genetics》1999,65(3):745-751
Benign adult familial myoclonic epilepsy is an autosomal dominant idiopathic epileptic syndrome characterized by adult-onset tremulous finger movement, myoclonus, epileptic seizures, and nonprogressive course. It was recently recognized in Japanese families. In this study, we report that the gene locus is assigned to the distal long arm of chromosome 8, by linkage analysis in a large Japanese kindred with a maximum two-point LOD score of 4.31 for D8S555 at recombination fraction of 0 (maximum multipoint LOD score of 5.42 for the interval between D8S555 and D8S1779). Analyses of recombinations place the locus within an 8-cM interval, between D8S1784 and D8S1694, in which three markers, D8S1830, D8S555, and D8S1779, show no recombination with the phenotypes. Although three other epilepsy-related loci on chromosome 8q have been recognized-one on chromosome 8q13-21 (familial febrile convulsion) and two others on chromosome 8q24 (KCNQ3 and childhood absence epilepsy)-the locus assigned here is distinct from these three epilepsy-related loci. This study establishes the presence of a new epilepsy-related locus on 8q23.3-q24.11. 相似文献
978.
979.
An adenovirus vector-mediated reverse genetics system for influenza A virus generation 总被引:1,自引:0,他引:1 下载免费PDF全文
Plasmid-based reverse genetics systems allow the generation of influenza A virus entirely from cloned cDNA. However, since the efficiency of virus generation is dependent on the plasmid transfection efficiency of cells, virus generation is difficult in cells approved for vaccine production that have low transfection efficiencies (e.g., Vero cells). Here we established an alternative reverse genetics system for influenza virus generation by using an adenovirus vector (AdV) which achieves highly efficient gene transfer independent of cell transfection efficiency. This AdV-mediated reverse genetics system will be useful for generating vaccine seed strains and for basic influenza virus studies. 相似文献
980.