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排序方式: 共有3138条查询结果,搜索用时 31 毫秒
121.
Aki Tomizawa Kazuhiro Nogawa Yuuka Watanabe Mitsuhiro Oishi Kumihiko Tanaka Kouichi Sakata 《Chronobiology international》2019,36(6):751-757
We investigated how differences in circadian rhythm type affect the health of workers engaged in shift work. Employees, who were newly hired in a steel company between 2007 and 2011, received the Morningness–Eveningness Questionnaire (MEQ) survey. The target participants were 153 male shift workers who were not being treated with any antihyperlipidemic drugs and underwent periodic physical examinations including blood tests at least twice. According to the score of the MEQ at the time of joining the company, we classified the subjects into five types. Longitudinal changes in serum lipid level were estimated among the circadian rhythm types adjusted for age, BMI, and other covariates using a linear mixed model. The regression coefficient of total cholesterol level in the “definitely and moderately morning” group was ?17.83 (95% confidence interval (CI): ?33.42 to ?2.23), and in the “intermediate ‘group’ was ?16.84 [95% CI: ?30.40 to ?3.28], compared to the moderate evening type.” The total cholesterol level was higher in the moderately evening type than in any of the other groups. Between the Morningness–Eveningness (ME) type and Low-density lipoprotein (LDL) cholesterol levels, compared with the “moderately evening type” group, the regression coefficient in the “intermediate type” group was ?16.08 (95% CI: ?28.79 to ?3.37), and in the “definitely and moderately morning type” group was ?17.50 [95% CI: ?32.11 to ?2.88]. The “moderately evening type” group had a higher LDL cholesterol level than any of the other groups. Evening-type circadian rhythm type shift workers are more prone to elevated serum lipid levels. 相似文献
122.
We investigated the in vitro stimulatory effect of ganglioside (GM3, GD1a, GD1b, GT1b, or GQ1b)-containing liposomes on human immune cells. The effect of ganglioside-containing liposomes on the concentration of cytoplasmic free calcium ions ([Ca2+]1) in human immunocytes was examined using the confocal laser fluorescence microscopic method. The GD1a- and GT1b-containing liposomes significantly increased [Ca2+]1 of human T lymphocytes compared with the GM3-, GD1b- and GQ1b-containing ones. The response of CD8+ and CD4+ cells was significantly higher than that of CD20+ cells. Our results show that the increase in [Ca2+]i may be caused by not the number of sialic acids contained in the gangliosides but the conformation of the sialic acid moiety to protrude exteriorly from the liposomal membrane surface, and that a sort of receptor recognizing the sialic acid moiety exists on human T lymphocytes (both CD8+ and CD4+ cells), which may be involved in the activation of the cells. The present results are almost the same as those obtained for the rat T lymphocyte system previously reported. This clearly confirms that a sort of ganglioside surely stimulates T lymphocytes directly, which is not species-specific but conserved in humans and rats among animal species. 相似文献
123.
Yamada K 《Molecular and cellular biochemistry》1999,190(1-2):39-45
Results of microcalorimetric titrations of calcium-binding proteins with calcium or magnesium have been reviewed and evaluated. Results were analyzed mostly in terms of heat capacity changes, which is most closely related to the structural changes of the molecule on metal binding. Two high-affinity sites of rabbit skeletal troponin C are distinguishable in terms of their affinity to calcium and associated enthalpy changes. Heat capacity changes on calcium binding to one of the two high-affinity sites is negative and is in the range ascribed to the ligand binding. In contrast, that to the other of the high-affinity sites is large and positive, indicating that a substantial area of hydrophobic groups become exposed to the solvent. In frog skeletal troponin C, the anomalous positive heat capacity changes occur in one of the low-affinity calcium-specific sites, so that this may be involved in the regulation of contraction. Unlike skeletal troponin C, both of the two high-affinity sites of cardiac troponin C show negative heat capacity changes. In calmodulin, heat capacity changes are positive but small, indicating that calcium binding may induce clustering of the hydrophobic residues on the surface of the molecule. In parvalbumins, heat capacity changes are negative, characteristic of most ligand binding. 相似文献
124.
Masuda T Ohmi K Yamaguchi H Hasegawa K Sugiyama T Matsuda Y Iino M Nonomura Y 《Molecular and cellular biochemistry》1999,190(1-2):99-104
Recently we have established an aortic smooth muscle cell line, p53LMAC01 obtained from p53 knockout mice. This cell line showed some differentiated properties which were accelerated by 5-azacytidine treatment [1]. In this study, further characterization of p53LMAC01 cell line was investigated according to cell growth and differentiation, and especially focused into the changes of cell feature, actin filaments' formation, and changes of intracellular calcium concentrations to sympathetic nerve transmitter, norepinephrine. While the cell feature was changed from flattened shape to extended form during 4 days, actin filaments were developing, arranging in parallel to longitudinal direction, and gathering under the surface membrane. In 11 days many cells died and detached from substrate, while actin filaments became poor except for the surface membrane in the remained cells. Appearance of calcium response to noradrenalin needed several days after passage as well as a morphological change of the cells for the extended form and development of actin filaments. The calcium response was maintained on 11 days, which coincided with the result that the cells hold actin filaments under the surface membrane. These results suggest that p53LMAC01 cell line maintains several differentiated characters of adult smooth muscle cell and that their expression needs several days after passage. 相似文献
125.
126.
Brap2 functions as a cytoplasmic retention protein for p21 during monocyte differentiation 总被引:5,自引:0,他引:5
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Asada M Ohmi K Delia D Enosawa S Suzuki S Yuo A Suzuki H Mizutani S 《Molecular and cellular biology》2004,24(18):8236-8243
The cell cycle inhibitor p21 plays an important role in monocytic cell differentiation, during which it translocates from the nucleus to cytoplasm. This process involves the negative regulation of the p21 nuclear localization signal (NLS). Here, we sought to determine the relationship between the cytoplasmic translocation of p21 and another molecule, Brap2, a cytoplasmic protein which binds the NLS of BRCA1 and was recently reported to inactivate KSR in the Ras-activating signal pathway under the name of IMP. We report that p21 and Brap2 directly interact, both in vitro and in vivo, in a manner requiring the NLS of p21 and the C-terminal portion of Brap2. When it is cotransfected with Brap2, p21 is expressed in the cytoplasm. Monocytic differentiation of the promyelomonocytic cell lines U937 and HL60 is associated with the upregulation of Brap2 expression concomitantly with the upregulation and cytoplasmic relocalization of p21. Our results underscore the role played by Brap2 in the process of cytoplasmic translocation of p21 during monocyte differentiation. 相似文献
127.
Yorimitsu M Muranaka S Sato EF Fujita H Abe K Yasuda T Inoue M Utsumi K 《Physiological chemistry and physics and medical NMR》2004,36(2):95-107
We previously showed that Ca2+-induced cyclosporin A-sensitive membrane permeability transition (MPT) of mitochondria occurred with concomitant generation of reactive oxygen species (ROS) and release of cytochrome c (Free Rad. Res.38, 29-35, 2004). To elucidate the role of alpha-tocopherol in MPT, we investigated the effect of alpha-tocopherol on mitochondrial ROS generation, swelling and cytochrome c release induced by Ca2+ or hydroxyl radicals. Biochemical analysis revealed that alpha-tocopherol suppressed Ca2+-induced ROS generation and oxidation of critical thiol groups of mitochondrial adenine nucleotide translocase (ANT) but not swelling and cytochrome c release. Hydroxyl radicals also induced cyclosporin A-sensitive MPT of mitochondria. alpha-Tocopherol suppressed the hydroxyl radical-induced lipid peroxidation, swelling and cytochrome c release from mitochondria. These results indicate that alpha-tocopherol inhibits ROS generation, ANT oxidation, lipid peroxidation and the opening of MPT, thereby playing important roles in the prevention of oxidative cell death. 相似文献
128.
129.
Leah?C.?Solberg Amber?E.?Baum Nasim?Ahmadiyeh Kazuhiro?Shimomura Renhua?Li Fred?W.?Turek Gary?A.?Churchill Joseph?S.?Takahashi Eva?E.?RedeiEmail author 《Mammalian genome》2004,15(8):648-662
The Wistar–Kyoto (WKY) rat exhibits physiological and behavioral similarities to endophenotypes of human depression. In the forced swim test (FST), a well-characterized antidepressant-reversible test for behavioral despair in rodents, WKYs express characteristics of behavioral despair; increased immobility, and decreased climbing. To map genetic loci linked to behavior in the FST, we conducted a quantitative trait loci (QTL) analysis of the segregating F2 generation of a WKY × Fisher 344 (F344) reciprocal intercross. Using linear-model-based genome scans to include covariate (sex or lineage)-by-QTL interaction effects, four significant QTL influencing climbing behavior were identified. In addition, we identified three, seven, and two suggestive QTL for climbing, immobility, and swimming, respectively. One of these loci was pleiotropic, affecting both immobility and climbing. As found in human linkage studies, several of these QTL showed sex- and/or lineage-dependent effects. A simultaneous search strategy identified three epistatic locus pairs for climbing. Multiple regression analysis was employed to characterize the joint contributions of these QTL and to clarify the sex- and lineage-dependent effects. As expected for complex traits, FST behavior is influenced by multiple QTL of small effect, each contributing 5%–10%, accounting for a total 10%–30% of the phenotypic variance. A number of loci mapped in this study share overlapping candidate regions with previously identified emotionality QTL in mice as well as with susceptibility loci recognized by linkage or genome scan analyses for major depression or bipolar disorder in humans. The presence of these loci across species suggests that these QTL may represent universal genetic factors contributing to mood disorders. 相似文献
130.
Suzuki Y Asano K Shiraishi Y Oguma T Shiomi T Fukunaga K Nakajima T Niimi K Yamaguchi K Ishizaka A 《Prostaglandins, leukotrienes, and essential fatty acids》2004,71(6):375-382
Thromboxane A2 receptor (TP) mediates bronchial smooth muscle cell (BSMC) contraction, airway hyperresponsiveness, and airway inflammation in patients with asthma. In the present study, a pathogenic role of TP activation in airway remodeling was examined using primary cultures of human BSMC. A TP agonist, I-BOP, concentration-dependently enhanced not only bromodeoxyuridine (BrdU) uptake but also cell proliferation of BSMC. A TP-selective antagonist, AA-2414, blocked the effects of I-BOP on both BrdU uptake and cell proliferation. I-BOP-induced BrdU uptake was significantly blocked by two non-selective tyrosine kinase inhibitors, genistein and herbimycin A, or a Src family tyrosine kinase inhibitor, PP2, but not by an inhibitor of epidermal growth factor (EGF) receptor-associated tyrosine kinase, AG1478. In conclusion, TP receptor activation causes DNA synthesis and cell proliferation of human BSMC by activating tyrosine kinases including Src, but not by EGF receptor transactivation. 相似文献