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21.
A series of (2-aryl-5-methylimidazol-4-ylcarbonyl)guanidines and (2-aryl-5-methyloxazol-4-ylcarbonyl)guanidines were synthesized and evaluated as NHE-1 inhibitors. The structure–activity relationships well matched those of furan derivatives, which were previously investigated. The (2,5-disubstituted)phenyl compounds showed better activities than the other analogues in both imidazole and oxazole compounds. Especially, 2-(2,5-dichlorophenyl)imidazole 52, and 2-(2-methoxy-5-chlorophenyl)imidazole 54 compounds exhibited potent cardioprotective efficacy both in vitro and in vivo as well as high NHE-1 inhibitory activities.  相似文献   
22.
To investigate the nanomechanics of the erythrocyte membrane we developed a hybrid model that couples the actin-spectrin network to the lipid bilayer. This model features a Fourier space Brownian dynamics model of the bilayer, a Brownian dynamics model of the actin protofilament, and a modified wormlike-chain model of the spectrin (including a cable-dynamics model to predict the oscillation in tension). This model enables us to predict the nanomechanics of single or multiple units of the protein network, the lipid bilayer, and the effect of their interactions. The present work is focused on the attitude of the actin protofilament at the equilibrium states coupled with the elevations of the lipid bilayer through their primary linkage at the suspension complex in deformations. Two different actin-spectrin junctions are considered at the junctional complex. With a point-attachment junction, large pitch angles and bifurcation of yaw angles are predicted. Thermal fluctuations at bifurcation may lead to mode-switching, which may affect the network and the physiological performance of the membrane. In contrast, with a wrap-around junction, pitch angles remain small, and the occurrence of bifurcation is greatly reduced. These simulations suggest the importance of three-dimensional molecular junctions and the lipid bilayer/protein network coupling on cell membrane mechanics.  相似文献   
23.
The aim of this study was to explore whether FAS ?670?A/G and ?1,377?G/A polymorphisms confer susceptibility to autoimmune rheumatic diseases. A meta-analysis was conducted on the associations between the FAS ?670?A/G and ?1,377?G/A polymorphisms and autoimmune rheumatic diseases using allele contrast, a recessive model, a dominant model, and an additive model. Thirteen articles with 21 comparison studies (16 on FAS ?670?A/G and 5 on ?1,377?G/A polymorphisms) including systemic lupus erythematosus (SLE), four systemic sclerosis, four Sjogren’s syndrome, three rheumatoid arthritis (RA), one juvenile idiopathic arthritis, and one spondyloarthropathy were available for the meta-analysis. Meta-analysis revealed an association between rheumatic diseases and the FAS ?670?A/G polymorphism in the dominant model (odds ratio [OR]?=?0.761, 95?% confidence interval [CI]?=?0.621–0.932, p?=?0.008]. Stratification by ethnicity indicated an association between the FAS ?670?G allele carrier and rheumatic diseases in Asian (OR?=?0.569, 95?% CI?=?0.409–0.791, p?=?0.001). Furthermore, stratification by disease indicated an association between the FAS ?670?G allele carrier and SLE and RA (OR?=?0.578, 95?% CI?=?0.358–0.934, p?=?0.025; OR?=?0.609, 95?% CI?=?0.398–0.934, p?=?0.023, respectively). The FAS ?670?G allele was negatively associated with SLE susceptibility. Meta-analysis of the FAS ?1,377?G/A polymorphism stratified by disease showed an association between the FAS ?1,377 A allele and SLE (OR?=?0.783, 95?% CI?=?0.613–0.997, p?=?0.047). Meta-analyses using the dominant model also showed a significant association in SLE (OR?=?0.712, 95?% CI?=?0.528–0.961, p?=?0.027). This meta-analysis demonstrates that the FAS ?670?A/G polymorphism confers susceptibility to rheumatic diseases in Asians and SLE and RA, and the FAS ?1,377?G/A polymorphism is associated with SLE susceptibility.  相似文献   
24.
Summary Deactivation ofCandida rugosa lipase was found to be complex. Hydrophobic interaction induced by iso-octane influenced the initial phase of deactivation, and increased the turn-over rate of the intermediate in the transition phase. After urea-treatment the structure of the last phase was not further influenced by thermal treatment, whereas that of initial phase was more sensitive to temperature change. Charge interaction was important in maintaining the structure during the deactivation, and especially anion charge might be a major factor.  相似文献   
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Hypercholesterolemia is a risk factor for coronary heart disease (CHD) and also could contribute to impaired immune response. The National Cholesterol Education Program Expert Panel recommends a therapeutic lifestyle change (TLC) diet to reduce the risk for CHD. We investigated the effects of changing from a high-fat Western diet to a low-fat diet in accordance with a TLC diet on immune functions of older adults with hypercholesterolemia to determine whether improving the lipid profile via dietary intervention would have beneficial effects on immune functions. In a double-blind study, 18 subjects consumed both a Western diet (38% fat) and a TLC diet (28% fat) for 32 days in a randomized order. Measures of cellular immune responses, including delayed-type hypersensitivity (DTH) response, in vitro lymphocyte proliferation, and interleukin (IL)-2 production, and production of proinflammatory mediators, including tumor necrosis factor-alpha, IL-6, IL-1beta, and prostaglandin E2, were determined. DTH response and lymphocyte proliferative response increased significantly (29% and 27%, respectively) after consumption of a TLC diet. Our results indicate that consumption of a TLC diet enhances T cell-mediated immune functions in older adults with elevated cholesterol level. This might be a clinically important benefit, considering the decline of T cell-mediated immune functions with aging and evidence of impaired immune function associated with hypercholesterolemia.  相似文献   
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The threat of a highly pathogenic avian influenza (HPAI) H5N1 virus causing the next pandemic remains a major concern. In this study, we evaluated the immunogenicity and efficacy of an inactivated whole-virus H5N1 pre-pandemic vaccine (MG1109) formulated by Green Cross Co., Ltd containing the hemagglutinin (HA) and neuraminidase (NA) genes of the clade 1 A/Vietnam/1194/04 virus in the backbone of A/Puerto Rico/8/34 (RgVietNam/04xPR8/34). Administration of the MG1109 vaccine (2-doses) in mice and ferrets elicited high HI and SN titers in a dose-dependent manner against the homologous (RgVietNam/04xPR8/34) and various heterologous H5N1 strains, (RgKor/W149/06xPR8/34, RgCambodia/04xPR8/34, RgGuangxi/05xPR8/34), including a heterosubtypic H5N2 (A/Aquatic bird/orea/W81/05) virus. However, efficient cross-reactivity was not observed against heterosubtypic H9N2 (A/Ck/Korea/H0802/08) and H1N1 (PR/8/34) viruses. Mice immunized with 1.9 μg HA/dose of MG1109 were completely protected from lethal challenge with heterologous wild-type HPAI H5N1 A/EM/Korea/W149/06 (clade 2.2) and mouse-adapted H5N2 viruses. Furthermore, ferrets administered at least 3.8 μg HA/dose efficiently suppressed virus growth in the upper respiratory tract and lungs. Vaccinated mice and ferrets also demonstrated attenuation of clinical disease signs and limited virus spread to other organs. Thus, this vaccine provided immunogenic responses in mouse and ferret models even against challenge with heterologous HPAI H5N1 and H5N2 viruses. Since the specific strain of HPAI H5N1 virus that would potentially cause the next outbreak is unknown, pre-pandemic vaccine preparation that could provide cross-protection against various H5 strains could be a useful approach in the selection of promising candidate vaccines in the future.  相似文献   
29.
To survive in a subzero environment, polar organisms produce ice-binding proteins (IBPs). These IBPs prevent the formation of large intracellular ice crystals, which may be fatal to the organism. Recently, a recombinant FfIBP (an IBP from Flavobacterium frigoris PS1) was cloned and produced in Pichia pastoris using fed-batch fermentation with methanol feeding. In this study, we demonstrate that FfIBP produced by P. pastoris has a glycosylation site, which diminishes the thermal hysteresis activity of FfIBP. The FfIBP expressed by P. pastoris exhibited a doublet on SDS-PAGE. The results of a glycosidase reaction suggested that FfIBP possesses complex N-linked oligosaccharides. These results indicate that the residues of the glycosylated site could disturb the binding of FfIBP to ice molecules. The findings of this study could be utilized to produce highly active antifreeze proteins on a large scale.  相似文献   
30.
An olfactory receptor protein of C. elegans, ODR-10, was expressed in Escherichia coli as a fusion protein, with GST and 6x His-tag. The expression of the target protein was analyzed by SDS-PAGE and Western blot, and was confirmed to be expressed at the membrane fraction of the host E. coli. The surface of a quartz crystal microbalance (QCM) was coated with crude membrane extracts, containing the expressed receptor protein, and the interaction between the olfactory receptor and various odorant molecules examined. Compared with other odorants, diacetyl (2,3-butanedione), known as a natural ligand for the ODR-10 receptor, interacted most strongly with the expressed protein. Various concentrations of diacetyl were applied to the expressed ODR-10 receptor, and the response of the QCM showed a linear relationship to the logarithmic value of the odorant concentration. This piezoelectric biosensor system, using olfactory receptor proteins expressed in E. coli, can be used in diagnostics, toxic chemical detection and the quality control of food.  相似文献   
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