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91.
We evaluated the effects of rowing on the morphology and function of the leg extensor muscle in old people. The area and
the power of the leg extensor muscle were measured in 15 oarsmen – age [mean (SD)] 65 (3) years; height 171 (4) cm, body mass
68 (6) kg – and in 15 sedentary men – age 66 (4) years, height 170 (4) cm, body mass 67 (7) kg – who were matched on the basis
of their body size. The leg extensor muscle area of the oarsmen was larger than that of the sedentary men [77.8 (5.4) vs 68.4
(5.1) cm2, P<0.05]. Also the bilateral leg extension power of the oarsmen was larger than that of the sedentary men [1,624 (217) vs 1,296
(232) W, P<0.05]. Thus, the leg extension power per the leg extensor muscle area was not significantly different between two groups
[20.9 (2.0) vs 19.9 (2.1) W·cm–2) and leg extension power was correlated to the leg extensor muscle area (59–89 cm2, r=0.74, P<0.001). Also the 2,000-m rowing ergometer time of the oarsmen [495 (14) s; range 479–520 s] was related to leg extensor muscle
area (68–89 cm2, r=0.63, P<0.01). The results suggest that rowing prevents age-related muscle wasting and weakness.
Electronic Publication 相似文献
92.
Distribution of eye- and arm-movement-related neuronal activity in the SEF and in the SMA and Pre-SMA of monkeys 总被引:4,自引:0,他引:4
We analyzed neuronal activity in the supplementary eye field (SEF), supplementary motor area (SMA), and presupplementary motor area (pre-SMA) during the performance of three motor tasks: capturing a visual target with a saccade, reaching one arm to a target while gazing at a visual fixation point, or capturing a target with a saccade and arm-reach together. Our data demonstrated that each area was involved in controlling the arm and eye movements in a different manner. Saccade-related neurons were found mainly in the SEF. In contrast, arm-movement-related neurons were found primarily in the SMA and pre-SMA. In addition, we found that the activity of both arm-movement- and saccade-related neurons differed depending on the presence or absence of an accompanying saccade or arm movement. Such context dependency was found in all three areas. We also discovered that activity preceding eye or arm movement alone, and eye and arm movement combined, appeared more often in the pre-SMA and SEF, suggesting their involvement in effector-independent aspects of motor behavior. Subsequent analysis revealed that the laterality of arm representation differed in the three areas: it was predominantly contralateral in the SMA but largely bilateral in the pre-SMA and SEF. 相似文献
93.
Saito S Iida A Sekine A Ogawa C Kawauchi S Higuchi S Ohno M Nakamura Y 《Journal of human genetics》2002,47(8):419-444
We screened DNAs from 48 Japanese individuals for single-nucleotide polymorphisms (SNPs) in genes encoding 13 cytochrome
P450 (CYP) enzymes and 14 aldehyde dehydrogenases (ALDHs) by directly sequencing their entire genomic regions except for repetitive
elements. This approach identified 810 SNPs and 96 insertion/deletion polymorphisms among the 27 genes. Of the 810 SNPs, 229
were identified among the CYP genes and 581 in the ALDH genes; of the total, 48 SNPs were located in 5′ flanking regions, 619 in introns, 91 in exons, and 52 in 3′ flanking regions.
These variants should contribute to studies designed to investigate possible correlations between genotypes and phenotypes
of disease susceptibility or responsiveness to drug therapy.
Received: April 23, 2002 / Accepted: April 25, 2002 相似文献
94.
Influence of PD‐L1 cross‐linking on cell death in PD‐L1‐expressing cell lines and bovine lymphocytes
Ryoyo Ikebuchi Satoru Konnai Tomohiro Okagawa Kazumasa Yokoyama Chie Nakajima Yasuhiko Suzuki Shiro Murata Kazuhiko Ohashi 《Immunology》2014,142(4):551-561
Programmed death‐ligand 1 (PD‐L1) blockade is accepted as a novel strategy for the reactivation of exhausted T cells that express programmed death‐1 (PD‐1). However, the mechanism of PD‐L1‐mediated inhibitory signalling after PD‐L1 cross‐linking by anti‐PD‐L1 monoclonal antibody (mAb) or PD‐1–immunogloblin fusion protein (PD‐1‐Ig) is still unknown, although it may induce cell death of PD‐L1+ cells required for regular immune reactions. In this study, PD‐1‐Ig or anti‐PD‐L1 mAb treatment was tested in cell lines that expressed PD‐L1 and bovine lymphocytes to investigate whether the treatment induces immune reactivation or PD‐L1‐mediated cell death. PD‐L1 cross‐linking by PD‐1‐Ig or anti‐PD‐L1 mAb primarily increased the number of dead cells in PD‐L1high cells, but not in PD‐L1low cells; these cells were prepared from Cos‐7 cells in which bovine PD‐L1 expression was induced by transfection. The PD‐L1‐mediated cell death also occurred in Cos‐7 and HeLa cells transfected with vectors only encoding the extracellular region of PD‐L1. In bovine lymphocytes, the anti‐PD‐L1 mAb treatment up‐regulated interferon‐γ (IFN‐γ) production, whereas PD‐1‐Ig treatment decreased this cytokine production and cell proliferation. The IFN‐γ production in B‐cell‐depleted peripheral blood mononuclear cells was not reduced by PD‐1‐Ig treatment and the percentages of dead cells in PD‐L1+ B cells were increased by PD‐1‐Ig treatment, indicating that PD‐1‐Ig‐induced immunosuppression in bovine lymphocytes could be caused by PD‐L1‐mediated B‐cell death. This study provides novel information for the understanding of signalling through PD‐L1. 相似文献
95.
96.
Nakagawa Y Murai T Hasegawa C Hirata M Tsuchiya T Yagami T Haishima Y 《Journal of biomedical materials research. Part B, Applied biomaterials》2003,66(1):347-355
Contamination by endotoxin of nine kinds of wound dressings made of natural biomaterials (calcium alginate, collagen, chitin, and poly-L-leucine) was examined with the use of water extracts. By applying the Limulus amoebocyte lysate (LAL) test, high concentrations of endotoxin were detected in extracts from three kinds of products made of calcium alginate. These extracts evoked fever in rabbits and induced the release of a proinflammatory (pyrogenic) cytokine, interleukin-6 (IL-6), from human monocytic cells (MM6-CA8). The effects disappeared when the extracts were treated with endotoxin-removing gel column chromatography or with an endotoxin antagonist, B464, confirming that the contaminating pyrogen was endotoxin. A noteworthy finding was that one of the endotoxin-containing extracts showed very weak IL-6-inducibility in human monocytic cells in contrast to its high pyrogenicity to rabbits. The discrepancy could be explained based on differences between humans and rabbits in sensitivity to the endotoxin, because the extract showed higher proinflammatory-cytokine (TNF-alpha)-inducibility in rabbit whole-blood cells (WBCs) than human WBCs. The results suggest that the LAL test is a useful method of detecting endotoxin contamination in wound dressings and the MM6-CA8 assay is a good supplement to the LAL test for evaluating pyrogenicity in humans accurately. 相似文献
97.
Ogoh S Yoshiga CC Secher NH Raven PB 《The journal of physiological sciences : JPS》2006,56(3):227-233
The influence of the carotid-cardiac baroreflex on blood pressure regulation was evaluated during supine rest and 40 degrees head-up tilt (HUT) in 9 healthy young subjects with and without full cardiac vagal blockade. The carotid baroreflex responsiveness, or maximal gain (G(MAX)), was assessed from the beat-to-beat changes in heart rate (HR) and mean arterial pressure (MAP) by the variable neck pressure and suction technique ranging in pressure from +40 to -80 Torr, with and without glycopyrrolate (12.0 +/- 1.0 microg/kg body weight; mean +/- SE). In the supine position, glycopyrrolate increased the HR to 91 +/- 3 bpm, from 54 +/- 3; MAP to 89 +/- 2 mmHg, from 76 +/- 2; and cardiac output to 6.8 +/- 0.3 l.min(-1), from 4.9 +/- 0.3 (P < 0.05). The G(MAX) of the carotid baroreflex control of HR was reduced to -0.06 +/- 0.01 bpm.mmHg(-1), from -0.30 +/- 0.02 (P < 0.05) with no significant effect on the G(MAX) of the carotid baroreflex control of MAP. During HUT the carotid baroreflex control of MAP was unchanged, though the G(MAX) of the carotid baroreflex control of HR was increased (P < 0.05). During HUT, central blood volume, assessed by electrical thoracic admittance, and total vascular conductance were decreased with and without glycopyrrolate. Furthermore, glycopyrrolate reduced G(MAX) of the carotid baroreflex control of HR during HUT (P < 0.05) with no significant effect on G(MAX) of the carotid baroreflex control of MAP. These data suggest that during supine rest and HUT-induced decreases in central blood volume, the carotid baroreflex control of HR is mediated primarily via parasympathetic activity. Furthermore, the maintenance of arterial blood pressure during postural stress is primarily mediated by arterial and cardiopulmonary reflex regulation of sympathetic activity and its effects on the systemic vasculature. 相似文献
98.
Localization of nuclear receptor subfamily 4, group A,member 3 (NR4A3) in Lewy body disease and multiple system atrophy 下载免费PDF全文
99.
Macroautophagy is a dynamic process whereby cytoplasmic molecules are sequestered within autophagosomes. Based on amino acid similarity, there exist two groups of mammalian autophagy-related gene (Atg) 8 homologues [microtubule-associated protein 1 light chain 3 (LC3) and γ-aminobutyric-acid type A receptor associated proteins (GABARAPs)], which play essential role in autophagosomal formation. Despite recent progress in studies on LC3, the other Atg8 homologues remain to be poorly understood, especially in pathological condition. In this study, we determined whether Atg8 homologues are affected in Lewy body disease, including Parkinson's disease (PD) and dementia with Lewy bodies (DLB). Our findings indicated that biochemical and pathological properties of LC3 were altered and that the level of LC3 was increased in an insoluble fraction from the brain of patients with DLB, whereas the level of GABARAPs was decreased in DLB. Furthermore, immunohistochemical staining revealed that both LC3 and GABARAPs were localized in Lewy bodies in PD and DLB. These findings suggest that autophagic function is impaired through alteration of Atg8 homologues in Lewy body disease. 相似文献
100.
Yukito Ichinose MD Yasuro Fukuyama MD Hiroshi Asoh MD Chie Ushijima MD Tatsuro Okamoto MD Jiro Ikeda MD Junichi Okamoto MD Maki Sakai MD 《The Annals of thoracic surgery》2003,76(6):1810-1814