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961.
962.
The cytoprotective action of the synthetic resveratrol (Resv) congener, E-3,3′,5,5′-tetrahydroxystilbene (designated as HST-1) against indomethacin (IND)-induced stomach ulceration has been established using a mice model. HST-1 reversed the adverse effects of IND on several inflammatory (myeloperoxidase, cytokines, adhesion molecules etc.) and ulcer-healing (cyclooxygenases, prostaglandin, growth factors and their receptors etc.) parameters in mice. More importantly, HST-1 down-regulated TNF-α and the TNF-α-mediated activation of NF-κB and JNK/MAPK pathways that are the key determinants in the IND-gastropathy. The effect of HST-1 on all these factors was significantly better than that of Resv, misoprostol, and omeprazole. HST-1 also did not induce small intestinal mucosal injury, unlike some of the proton pump inhibitors. On the other hand, Resv reduced activation of the prosurvival ERK1/2 pathway that may explain its contraindicative property in the gastrointestinal tract.  相似文献   
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964.
Molecular and Cellular Biochemistry - Heart failure (HF) is a functional lack of myocardial performance due to a loss of molecular control over increases in calcium and ROS, resulting in...  相似文献   
965.
We have shown that the interaction of pepstatin A with human immunodeficiency virus-1 protease (HIV-1 protease) can be characterized by a high-affinity mode (Ki = 478 +/- 27 nM), resulting in pure competitive inhibition of the hydrolytic activity of HIV-1 protease toward the fluorogenic substrate. Binding of pepstatin in this mode induces a blue shift in the endogenous fluorescence arising from the tryptophan residues in HIV-1 protease. This shift is maximal in the presence of 10 microM pepstatin. Haloperidol, in contrast, interacts with HIV-1 protease with weaker affinity (Ki = 19 +/- 1 microM) in a mode which results in pure noncompetitive inhibition of the hydrolytic activity of HIV-1 protease. Binding of haloperidol in this mode induces a red shift in the endogenous fluorescence arising from the tryptophan residues in HIV-1 protease. This shift is maximal in the presence of 200 microM haloperidol. Addition of both pepstatin and haloperidol at concentrations in the range of their Ki values results in additive inhibition of the hydrolytic activity of HIV-1 protease, as well as an additive effect on the tryptophan fluorescence of protease. However, at saturating concentrations of pepstatin and haloperidol, the effect of haloperidol was predominant, as measured by the changes in the intrinsic fluorescence of HIV-1 protease.  相似文献   
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In order to assess a new strategy of DNA vaccine for a more complete understanding of its action in immune response, it is important to determine the in vivo biodistribution fate and antigen expression. In previous studies, our group focused on the prophylactic and therapeutic use of a plasmid DNA encoding the Mycobacterium leprae 65-kDa heat shock protein (Hsp65) and achieved an efficient immune response induction as well as protection against virulent M. tuberculosis challenge. In the present study, we examined in vivo tissue distribution of naked DNA-Hsp65 vaccine, the Hsp65 message, genome integration and methylation status of plasmid DNA. The DNA-Hsp65 was detectable in several tissue types, indicating that DNA-Hsp65 disseminates widely throughout the body. The biodistribution was dose-dependent. In contrast, RT-PCR detected the Hsp65 message for at least 15 days in muscle or liver tissue from immunized mice. We also analyzed the methylation status and integration of the injected plasmid DNA into the host cellular genome. The bacterial methylation pattern persisted for at least 6 months, indicating that the plasmid DNA-Hsp65 does not replicate in mammalian tissue, and Southern blot analysis showed that plasmid DNA was not integrated. These results have important implications for the use of DNA-Hsp65 vaccine in a clinical setting and open new perspectives for DNA vaccines and new considerations about the inoculation site and delivery system.  相似文献   
968.
Molecular Biology Reports - The metazoan mitogenomes usually display conserved gene arrangement while thrips are known for their extensive gene rearrangement, and duplication of the control region....  相似文献   
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970.

Background  

Enzymes belonging to the same super family of proteins in general operate on variety of substrates and are inhibited by wide selection of inhibitors. In this work our main objective was to expand the scope of studies that consider only the catalytic and binding pocket amino acids while analyzing enzyme specificity and instead, include a wider category which we have named the Interface Forming Residues (IFR). We were motivated to identify those amino acids with decreased accessibility to solvent after docking of different types of inhibitors to sub classes of serine proteases and then create a table (matrix) of all amino acid positions at the interface as well as their respective occupancies. Our goal is to establish a platform for analysis of the relationship between IFR characteristics and binding properties/specificity for bi-molecular complexes.  相似文献   
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