Ryoichi Nagatomi

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BACKGROUND Although considerable experimental and animal evidence shows that green tea may possess potent activities of neuroprotection, neurorescue, and amyloid precursor protein processing that may lead to cognitive enhancement, no human data are available. OBJECTIVE The objective was to examine the association between green tea consumption and(More)
Muscle satellite cells are the resident stem cells of adult skeletal muscle. Here, we have examined the role of the multifunctional protein presenilin-1 (PS1) in satellite cell function. PS1 acts as a crucial component of the gamma-secretase complex, which is required to cleave single-pass transmembrane proteins such as Notch and amyloid-beta precursor(More)
BACKGROUND Interleukin (IL)-6 is locally produced in skeletal muscles and shows a remarkable increase in plasma after eccentric exercises. OBJECTIVE To elucidate the cell types in the muscles responsible for IL-6 production after eccentric exercises. STUDY DESIGN Controlled laboratory study. METHODS An eccentric contraction model was made using(More)
The aim of this study was to elucidate the mechanism responsible for lymphopenia after exercise. Seven young healthy men volunteered for this study. Peripheral blood mononuclear cells (PBMC) were cultured with cortisol and analyzed for C-X-C motif chemokine receptor 4 (CXCR4) expression by flow cytometry. To determine the effects of exercise, subjects(More)
Although there is ample evidence supporting the effectiveness of physical activity in the prevention and treatment of osteoporosis, there are no previous studies to examine the effect of office-based brief high-impact exercise (HIE) on bone mineral density (BMD) in healthy premenopausal women. This study evaluated the effects of office-based HIE on BMD in(More)
PURPOSE We evaluated the association of nocturia with fracture and death in a large, community based sample of Japanese individuals 70 years old or older. MATERIALS AND METHODS The baseline in this population based study was determined in 2003 by an extensive health interview with each participant. In this study we followed 784 individuals with a mean ±(More)
Myofibroblasts are one of the key cellular components involved in fibrosis of skeletal muscle as well as in other tissues. Transforming growth factor-beta1 (TGF-beta1) stimulates differentiation of mesenchymal cells into myofibroblasts, but little is known about the regulatory mechanisms of myofibroblastic differentiation. Since Notch2 was shown to be(More)
Changes elicited by physical exercise in the numbers or the activity of blood T lymphocytes, NK cells and neutrophils are sometimes considered as indicators of altered immunocompetence. By comparing the pathological conditions, in which the changes in the numbers of cells resemble observations in the exercise studies, however we notice large discrepancies(More)
We analyzed the role of Hypoxia-inducible factor (HIF)-1alpha in myoblast differentiation by examining the expression and regulation of HIF-1alpha in proliferating and differentiating C2C12 myoblast, and by knocking down HIF-1alpha of C2C12 myoblasts with small interfering RNA (siRNA), given that HIF-1alpha has been shown to be involved in differentiative(More)
β(2) agonists reduce the frequency of exacerbations in patients with bronchial asthma and chronic obstructive pulmonary disease caused by respiratory virus infection. β(2) agonists reduce the production of pro-inflammatory cytokines. However, the inhibitory effects of β(2) agonists on the infection of rhinovirus, the major cause of exacerbations, have not(More)