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141.
Data presented in this paper show that the size of the endogenous coenzyme Q (CoQ) pool is not a limiting factor in the activation of mitochondrial glycerophosphate-dependent respiration by exogenous CoQ(3), since successive additions of succinate and NADH to brown adipose tissue mitochondria further increase the rate of oxygen uptake. Because the inhibition of glycerophosphate-dependent respiration by oleate was eliminated by added CoQ(3), our data indicate that the activating effect of CoQ(3) is related to the release of the inhibitory effect of endogenous free fatty acids (FFA). Both the inhibitory effect of FFA and the activating effect of CoQ(3) could be demonstrated only for glycerophosphate-dependent respiration, while succinate- or NADH-dependent respiration was not affected. The presented data suggest differences between mitochondrial glycerophosphate dehydrogenase and succinate or NADH dehydrogenases in the transfer of reducing equivalents to the CoQ pool. 相似文献
142.
Elias E Lalun N Lorenzato M Blache L Chelidze P O'Donohue MF Ploton D Bobichon H 《Experimental cell research》2003,291(1):176-188
143.
Ivo Šafařík Pavel Mucha Jiří Pechoč Jaroslav Stoklasa Mirka Šafaříková 《Biotechnology letters》2001,23(11):851-855
A Davis tube (a matrix-free, flow-through magnetic separator used mainly in mineral processing) has been tested for separation of magnetic affinity biopolymer adsorbents from larger volumes of suspensions. Both magnetic chitosan and magnetic cross-linked erythrocytes could be efficiently separated from litre volumes of suspensions. Up to 90% adsorbent recovery was achieved under optimised separation conditions. 相似文献
144.
Bernátová I Pechánová O Babál P Kyselá S Stvrtina S Andriantsitohaina R 《American journal of physiology. Heart and circulatory physiology》2002,282(3):H942-H948
The effects of the red wine polyphenolic compounds (Provinol) on hypertension, left ventricular hypertrophy, myocardial fibrosis, and vascular remodeling were investigated after chronic inhibition of nitric oxide (NO) synthase by administration of N(G)-nitro-L-arginine methyl ester (L-NAME) to rats. Rats were divided into four groups: a control group, a group treated for 4 wk with L-NAME (40 mg x kg(-1) x day(-1)), and two groups treated with L-NAME followed by 3 wk of either spontaneous recovery or recovery with Provinol treatment (40 mg x kg(-1) x day(-1)). Administration of Provinol produced a greater readiness of the decrease in blood pressure than that in the spontaneous recovery group. Provinol significantly depressed myocardial fibrosis and expedited the decrease in aortic cross-sectional area, the increase in endothelium-dependent relaxation, and the decrease in contraction of the aorta. These effects of Provinol were associated with a greater increase of NO synthase activity in the left ventricle and the aorta. The present study provides evidence that Provinol accelerates the regression of blood pressure and improves structural and functional cardiovascular changes produced by chronic inhibition of NO synthesis. 相似文献
145.
Stiborová M Simánek V Frei E Hobza P Ulrichová J 《Chemico-biological interactions》2002,140(3):231-242
Using the 32P-postlabeling assay, we investigated the ability of quaternary benzo[c]phenanthridine alkaloids, sanguinarine, chelerythrine and fagaronine, to form DNA adducts in vitro. Two enhanced versions of the assay (enrichment by nuclease P1 and 1-butanol extraction) were utilized in the study. Hepatic microsomes of rats pre-treated with beta-naphthoflavone or those of uninduced rats, used as metabolic activators, were incubated in the presence of calf thymus DNA and the alkaloids, with NADPH used as a cofactor. Under these conditions sanguinarine and chelerythrine, but not fagaronine, formed DNA adducts detectable by 32P-postlabeling. DNA adduct formation by both alkaloids was found to be concentration dependent. When analyzing different atomic and bond indices of the C11-C12 bond (ring B) in alkaloid molecules we found that fagaronine behaved differently from sanguinarine and chelerythrine. While sanguinarine and chelerythrine showed a preference for electrophilic attack indicating higher potential to be activated by cytochrome P450, fagaronine exhibited a tendency for nucleophilic attack. Our results demonstrate that sanguinarine and chelerythrine are metabolized by hepatic microsomes to species, which generate DNA adducts. 相似文献
146.
Expression of T-cadherin in the rat carotid artery wall after balloon injury and in different rat organs 总被引:1,自引:0,他引:1
Kudriashova EIu Bashtrykov PP Ivanov DB Antropova IuG Il'inskaia OP Tararak EM Bochkov VN Parfenova EV 《Tsitologiia》2002,44(3):285-295
T-cadherin is an unusual glycosilphosphatidylinositol (GPI)-anchored member of the cadherin family of cell adhesion proteins. In contrast to classical cadherins, tissue distribution of T-cadherin so far remained unknown. We examined tissue distribution of T-cadherin in rats using Western blotting and immunohistochemical method. Our results show that T-cadherin is expressed in all types of muscles (cardiac, striated, and smooth muscles), in brain neurons, and spinal cord, in the vessel endothelium, at the apical pole of intestinal villar epithelium, in the basal layer of skin, and eosophagal epithelium. Blood-derived and lymphoid cells as well as connective tissue were T-cadherin-negative. The highest level of T-cadherin expression was revealed in the cardiovascular system. Although T-cadherin was detected in smooth muscle cells, its role in the intimal thickening and restenosis is not known. We examined T-cadherin expression within 1-28 days after balloon injury of rat left carotid arteries. T-cadherin expression was valued immunohistochemically with semiquantitative method. In uninjured arteries, T-cadherin was expressed in endothelial (vWF-positive) cells, and smooth muscle (alpha-actin-positive) cells (SMCs). After denudation of arterial wall, T-cadherin was present both in the media and neointima. We revealed dynamics of T-cadherin expression in the media of injured artery: an essential increase being registered at the stage of cell migration and proliferation in the media and neointima (1-7 days), followed by its decrease to the baseline level (10-28 days). The high upregulation of T-cadherin expression in the media and neointima during migration and proliferation of vascular cells after vessel injury enables us to suggest the involvement of T-cadherin in vessel remodeling after balloon catheter injury. 相似文献
147.
Gromov PS Østergaard M Gromova I Celis JE 《Progress in biophysics and molecular biology》2002,80(1-2):3-22
Decoding of the genome information in terms of regulation and function will be the next great challenge in the life sciences in this millennium and indeed, today we are experiencing a rapid explosion of technology for the high throughput expression analysis of genes and their products (functional genomics). In particular, the field of proteomics is booming as proteins are often the functional molecules and represent important targets for the pharmaceutical industry. The proteomic technology is complex, and comprises a plethora of state-of-the-art techniques to resolve, identify and detect their interacting partners, as well as to store and communicate protein information in comprehensive two-dimensional polyacrylamide gel electrophoresis (2D PAGE) databases. Besides annotating the genome, these databases will offer a global approach to the study of gene expression both in health and disease. Here, we review the current status of human 2D PAGE databases that we are systematically constructing for the study of bladder cancer and skin ageing. 相似文献
148.
TFIIH plays an essential role in RNA polymerase I transcription 总被引:7,自引:0,他引:7
149.
Barinka C Rinnová M Sácha P Rojas C Majer P Slusher BS Konvalinka J 《Journal of neurochemistry》2002,80(3):477-487
Glutamate carboxypeptidase II (GCPII, EC 3.4.17.21) is a membrane peptidase expressed in a number of tissues such as kidney, prostate and brain. The brain form of GCPII (also known as NAALADase) cleaves N-acetyl-aspartyl glutamate to yield free glutamate. Animal model experiments show that inhibition of GCPII prevents neuronal cell death during experimental ischaemia. GCPII thus represents an important target for the treatment of neuronal damage caused by excess glutamate. In this paper we report expression of an extracellular portion of human glutamate carboxypeptidase II (amino acids 44-750) in Drosophila Schneider's cells and its purification to homogeneity. A novel assay for hydrolytic activity of recombinant human GCPII (rhGCPII), based on fluorimetric detection of released alpha-amino groups was established, and used for its enzymological characterization. rhGCPII does not show dipeptidylpeptidase IV-like activity assigned to the native form of the enzyme previously. Using a complete set of protected dipeptides, substrate specificity of rhGCPII was elucidated. In addition to the previously described substrates, four novel compounds, Ac-Glu-Met, Ac-Asp-Met and, surprisingly, Ac-Ala-Glu and Ac-Ala-Met were identified as substrates for GCPII, and their respective kinetic constants determined. The glycosylation of rhGCPII was found indispensable for the enzymatic activity. 相似文献
150.
Styrene is an important industrial chemical that has shown genotoxicity in many toxicology assays. This is believed to be related to the DNA-binding properties of styrene-7,8-oxide (SO), a major metabolite of styrene. In this review, we have summarized knowledge on various aspects of styrene genotoxicity, especially in order to understand the formation and removal of primary DNA lesions, and the usefulness of biomarkers for risk assessment. Biological significances of specific DNA adducts and their role in the cascade of genotoxic events are discussed. Links between markers of external and internal exposure are evaluated, as well as metabolic aspects leading to the formation of DNA adducts and influencing biomarkers of biological effect. Finally, we suggest a design of a population study, which may contribute to our understanding genotoxic events in the exposure either to single xenobiotic or complex mixture. 相似文献