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71.
This study determined the physical fitness component that contributes to improving and maintaining health status for each age group as well as quantifying the degree of the relationship between health status and physical fitness in middle-aged and elderly females. The participants were 2,371 females aged 30 to 69 years. Ten physical fitness tests and medical checkups were performed. The participants were divided into a healthy group and an unhealthy group according to health status. Multiple discriminant analysis was applied to the multivariate data. Correct discriminant probabilities of the multiple discriminant function to discriminate the healthy and unhealthy groups for females ranged from 63.0% to 77.5%. These results suggest that there is a relatively high relationship between health status and physical fitness level for middle-aged and elderly females. With each individual's discriminant score calculated by the obtained multiple discriminant function as the index of the degree of health, the Pearson's correlation coefficient of the discriminant score and the performance in each physical fitness test were calculated. The aging change from 30 to 69 years old was classified into four patterns according to the contribution. The result of this study is considered to be useful as objective data to prepare an exercise program considering the contribution of the physical fitness component of health status. 相似文献
72.
This study aimed to determine the accuracy of segmental body composition variables estimated by single-frequency BIA with 8-point contact electrodes (SF-BIA8), compared with dual-energy X-ray absorptiometry (DXA). Subjects were 72 obese Japanese adults (43 males and 29 females) aged 30 to 66 years. Segmental body composition variables (fat free mass: FFM, fat mass: FM, and percent fat mass: %FAT) were measured by these techniques. The correlations between impedance values and FFM measured by DXA were calculated. To examine the consistency in predicted values (SF-BIA8) with the reference (DXA), significant mean differences were tested by t-test and the degree of the difference was assessed by effect size. Correlations between the reference and predicted values were calculated. Additionally, the standard error of estimation (SEE) when estimating the reference from the predictor and the relative value of the SEE to the mean value of the DXA measurement (%SEE) were calculated. Systematic error was examined by Bland-Altman plots. High correlations were found between impedance and FFM measured by SF-BIA8. FFM in the extremities showed high correlations with the reference values, but systematic error was found. SF-BIA8 tended to overestimate FFM in the trunk. The consistencies in %FAT and FM with the reference value are inferior to those for FFM, and SEE values in %FAT and FM were greater than those for FFM. The accuracy of the estimated values in the trunk (FFM, %FAT, and FM) are inferior to those of the total body and extremities. 相似文献
73.
We have recently shown that autophagy is induced by ischemia and reperfusion in the mouse heart in vivo. Ischemia stimulates autophagy through an AMP activated protein kinase (AMPK)-dependent mechanism, whereas reperfusion after ischemia stimulates autophagy through a Beclin 1-dependent, but AMPK-independent, mechanism. Autophagy plays distinct roles during ischemia and reperfusion: autophagy may be protective during ischemia, whereas it may be detrimental during reperfusion. We will discuss the role of AMPK in mediating autophagy during myocardial ischemia in vivo. 相似文献
74.
Diversity of Ca2+-induced morphology revealed by morphological phenotyping of Ca2+-sensitive mutants of Saccharomyces cerevisiae 下载免费PDF全文
Yeast cell morphology can be treated as a quantitative trait using the image processing software CalMorph. In the present study, we investigated Ca(2+)-induced morphological changes in Ca(2+)-sensitive (cls) mutants of Saccharomyces cerevisiae, based on the discovery that the characteristic Ca(2+)-induced morphological changes in the Ca(2+)-sensitive mutant zds1 reflect changes in the Ca(2+) signaling-mediated cell cycle control pathway. By applying hierarchical cluster analysis to the quantitative morphological data of 58 cls mutants, 31 of these mutants were classified into seven classes based on morphological similarities. The patterns of morphological change induced by Ca(2+) in one class differed from those of another class. Based on the results obtained using versatile methods for phenotypic analysis, we conclude that a high concentration of Ca(2+) exerts a wide variety of effects on yeast and that there are multiple Ca(2+)-regulatory pathways that are distinct from the Zds1p-related pathway. 相似文献
75.
Nishida K Yamaguchi O Hirotani S Hikoso S Higuchi Y Watanabe T Takeda T Osuka S Morita T Kondoh G Uno Y Kashiwase K Taniike M Nakai A Matsumura Y Miyazaki J Sudo T Hongo K Kusakari Y Kurihara S Chien KR Takeda J Hori M Otsu K 《Molecular and cellular biology》2004,24(24):10611-10620
The molecular mechanism for the transition from cardiac hypertrophy, an adaptive response to biomechanical stress, to heart failure is poorly understood. The mitogen-activated protein kinase p38alpha is a key component of stress response pathways in various types of cells. In this study, we attempted to explore the in vivo physiological functions of p38alpha in hearts. First, we generated mice with floxed p38alpha alleles and crossbred them with mice expressing the Cre recombinase under the control of the alpha-myosin heavy-chain promoter to obtain cardiac-specific p38alpha knockout mice. These cardiac-specific p38alpha knockout mice were born normally, developed to adulthood, were fertile, exhibited a normal life span, and displayed normal global cardiac structure and function. In response to pressure overload to the left ventricle, they developed significant levels of cardiac hypertrophy, as seen in controls, but also developed cardiac dysfunction and heart dilatation. This abnormal response to pressure overload was accompanied by massive cardiac fibrosis and the appearance of apoptotic cardiomyocytes. These results demonstrate that p38alpha plays a critical role in the cardiomyocyte survival pathway in response to pressure overload, while cardiac hypertrophic growth is unaffected despite its dramatic down-regulation. 相似文献
76.
Nuki Y Uchinokura S Miyata S Fukushima T Hamasuna R Nakano S Wakisaka S Akiyama Y Itoh H Kataoka H 《Human cell》2004,17(3):145-150
A cell line designated NYGM was established from a human cerebral glioblastoma multiforme (GBM) obtained from a 75-year-old Japanese woman. The cell line has grown slowly without interruption and has been propagated continuously by serial passages (more than 80 passage) during the past 3 years. The cultured cells were fusiform or polyhedral in shape. The population doubling time was 24 hours. The chromosomal number varied between 77 and 88, with modal chromosomal number of 84. NYGM cells concomitantly expressed MET receptor tyrosine kinase (a product of c-met protooncogene) and its ligand HGF/SF (hepatocyte growth factor/scatter factor), as well as HGF activator and HGF activator inhibitors. The cells might be useful for the study of pericellular regulation of HGF/SF-MET signaling and HGF activation of GBM cells. 相似文献
77.
Chondrosarcoma of the urinary bladder and establishment of a human chondrosarcoma cell line (OCUU-6)
Chondrosarcoma is a very rare tumor of the urinary bladder, with only 4 cases reported to date. In this study, we report on a case of a 73-year-old male who presented bladder mass and right hydroureteronephrosis. Radical cystectomy, right nephrectomy and left ureterocutaneoustomy were performed, and histological study disclosed chondrosarcoma of the urinary bladder. As reported in other cases, the tumor was highly aggressive with a short clinical course, and the patient died of carcinomatous pleuritis at one month after surgery. Subsequently, we successfully established a human chondrosarcoma cell line (OCUU-6) from the pleural effusion of the patient. 相似文献
78.
Escherichia coli outer-membrane endoprotease OmpT has suitable properties for processing fusion proteins to produce peptides and proteins. However, utilization of this protease for such production has been restricted due to its generally low cleavage efficiency at Arg (or Lys)-Xaa, where Xaa is a nonbasic N-terminal amino acid of a target polypeptide. The objective of this study was to generate a specific and efficient OmpT protease and to utilize it as a processing enzyme for producing various peptides and proteins by converting its substrate specificity. Since OmpT Asp(97) is proposed to interact with the P1' amino acid of its substrates, OmpT variants with variations at Asp(97) were constructed by replacing this amino acid with 19 natural amino acids to alter the cleavage specificity at Arg (P1)-Xaa (P1'). The variant OmpT that had a methionine at this position, but not the wild-type OmpT, efficiently cleaved a fusion protein containing the amino acid sequence -Arg-Arg-Arg-Ala-Arg downward arrow motilin, in which motilin is a model peptide with a phenylalanine at the N terminus. The OmpT variants with leucine and histidine at position 97 were useful in releasing human adrenocorticotropic hormone (1-24) (serine at the N terminus) and human calcitonin precursor (cysteine at the N terminus), respectively, from fusion proteins. Motilin was produced by this method and was purified up to 99.0% by two chromatographic steps; the yield was 160 mg/liter of culture. Our novel method in which the OmpT variants are used could be employed for production of various peptides and proteins. 相似文献
79.
Activated microglia have been suggested to produce a cytotoxic cytokine, tumor necrosis factor alpha (TNF alpha), in many pathological brains. Thus, determining the molecular mechanism of this induction and suppression has been the focus of a great deal of research. Using lipopolysaccharide (LPS) as an experimental inducer of TNF alpha, we investigated the regulatory mechanism by which TNFalpha is induced or suppressed in microglia. We found that LPS-induced TNF alpha is suppressed by pretreatment with the p38 mitogen-activated protein kinase (p38MAPK) inhibitor SB203580. Similar suppression was achieved by pretreatment with specific protein kinase C (PKC) inhibitors, G?6976, myristoylated pseudosubstrate (20-28), and bisindolylmaleimide. These results suggest that PKC alpha activity as well as p38MAPK activity is associated with TNF alpha induction in LPS-stimulated microglia. The requirement of PKC alpha in LPS-dependent TNFalpha induction was verified in PKC alpha-downregulated microglia which could be induced by phorbol-12-myristate-13-acetate pretreatment. Simultaneously, PKC alpha was found to be requisite for the activation of p38MAPK in LPS-stimulated microglia. In addition, the PKC alpha levels in the LPS-stimulated microglia were observed to decrease in response to the p38MAPK inhibitor, indicating that the PKC alpha levels are regulated by the p38MAPK activity. We therefore concluded that PKC alpha and p38MAPK are interactively linked to the signaling cascade inducing TNFalpha in LPS-stimulated microglia, and that in this cascade, PKC alpha is requisite for the activation of p38MAPK, leading to the induction of TNF alpha. 相似文献
80.