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Nishi-Tokyo-shi, Japan

Showa Women's University is a women's private university in Setagaya, Tokyo, Japan. It also contains a school with all levels from kindergarten to high school Wikipedia.


Kano Y.,University of Electro - Communications | Miura S.,University of Shizuoka | Eshima H.,University of Electro - Communications | Ezaki O.,Showa Womens University | Poole D.C.,Kansas State University
Journal of Applied Physiology | Year: 2014

During contractions, regulation of microvascular oxygen partial pressure (PmvO2), which drives blood-myocyte O2 flux, is a function of skeletal muscle fiber type and oxidative capacity and can be altered by exercise training. The kinetics of PmvO2 during contractions in predominantly fast-twitch muscles evinces a more rapid fall to far lower levels compared with slow-twitch counterparts. Peroxisome proliferator- activated receptor γ coactivator 1α (PGC-1α) improves endurance performance, in part, due to mitochondrial biogenesis, a fiber-type switch to oxidative fibers, and angiogenesis in skeletal muscle. We tested the hypothesis that improvement of exercise capacity by genetic overexpression of PGC-1α would be associated with an altered PmvO2 kinetics profile of the fast-twitch (white) gastrocnemius during contractions toward that seen in slow-twitch muscles (i.e., slowed response kinetics and elevated steady-state PmvO2). Phosphorescence quenching techniques were used to measure PmvO2 at rest and during separate bouts of twitch (1 Hz) and tetanic (100 Hz) contractions in gastrocnemius muscles of mice with overexpression of PGC-1α and wild-type littermates (WT) mice under isoflurane anesthesia. Muscles of PGC-1α mice exhibited less fatigue than WT (P < 0.01). However, except for the PmvO2 response immediately following onset of contractions, WT and PGC-1α mice demonstrated similar PmvO2 kinetics. Specifically, the time delay of the PmvO2 response was shortened in PGC-1α mice compared with WT (1 Hz: WT, 6.6 ± 2.4 s; PGC-1α, 2.9 ± 0.8 s; 100 Hz: WT, 3.3 ± 1.1 s, PGC-1α, 0.9 ± 0.3 s, both P < 0.05). The ratio of muscle force to PmvO 2 was higher for the duration of tetanic contractions in PGC-1α mice. Slower dynamics and maintenance of higher PmvO2 following muscle contractions is not obligatory for improved fatigue resistance in fast-twitch muscle of PGC-1α mice. Moreover, overexpression of PGC-1α may accelerate O2 utilization kinetics to a greater extent than O2 delivery kinetics. Copyright © 2014 the American Physiological Society. Source


Yamazaki T.,Japan National Institute of Health Sciences | Kishimoto K.,Japan National Institute of Health Sciences | Ezaki O.,Japan National Institute of Health Sciences | Ezaki O.,Showa Womens University
Journal of Lipid Research | Year: 2012

Postprandial hyperlipidemia (lipemia) is a risk factor for atherosclerosis. However, mouse models of postprandial hyperlipidemia have not been reported. Here, we report that ddY mice display marked postprandial hypertriglyceridemia in response to dietary fat. In ddY mice, the fasting serum total triacylglyceride (TG) concentration was 134 mg/dl, which increased to 571 mg/dl after an intragastric safflower oil load (0.4 ml/mouse). In C57BL/6J mice, these concentrations were 57 and 106 mg/dl, respectively. By lipoprotein analysis, ddY mice showed increases in chylomicron-and VLDL-sized TG fractions (remnants and VLDL) after fat load. In C57BL/6J mice, post-heparin plasma LPL activity after fat load was increased 4.8-fold relative to fasting. However, in ddY mice, the increase of LPL activity after fat load was very small (1.2-fold) and not significant. High fat feeding for 10 weeks led to obesity in ddY mice. A difference in LPL amino acid composition between C57BL/6J and ddY mice was detected but was deemed unlikely to cause hypertriglyceridemia because hypertriglyceridemia was not evident in other strains harboring the ddY-type LPL sequence. These findings indicate that postprandial hypertriglyceridemia in ddY mice is induced by decreased LPL activity after fat load and is associated with obesity induced by a high-fat diet. Copyright © 2012 by the American Society for Biochemistry and Molecular Biology, Inc. Source


Yamanaka K.,Showa Womens University | Kadota H.,University of Tokyo | Kadota H.,Kochi University of Technology | Nozaki D.,University of Tokyo
Frontiers in Human Neuroscience | Year: 2013

Transcranial magnetic stimulation (TMS) has often been used in conjunction with electroencephalography (EEG), which is effective for the direct demonstration of cortical reactivity and corticocortical connectivity during cognitive tasks through the spatio-temporal pattern of long-latency TMS-evoked potentials (TEPs). However, it remains unclear what pattern is associated with the inhibition of a planned motor response. Therefore, we performed TMS-EEG recording during a go/stop task, in which participants were instructed to click a computer mouse with a right index finger when an indicator that was moving with a constant velocity reached a target (go trial) or to avoid the click when the indicator randomly stopped just before it reached the target (stop trial). Single-pulse TMS to the left (contralateral) or right (ipsilateral) motor cortex was applied 500 ms before or just at the target time. TEPs related to motor execution and inhibition were obtained by subtractions between averaged EEG waveforms with and without TMS. As a result, in TEPs induced by both contralateral and ipsilateral TMS, small oscillations were followed by a prominent negative deflection around the TMS site peaking at approximately 100 ms post-TMS (N100), and a less pronounced later positive component (LPC) over the broad areas that was centered at the midline-central site in both go and stop trials. However, compared to the pattern in go and stop trials with TMS at 500 ms before the target time, N100 and LPC were differently modulated in the go and stop trials with TMS just at the target time. The amplitudes of both N100 and LPC decreased in go trials, while the amplitude of LPC decreased and the latency of LPC was delayed in both go and stop trials. These results suggested that TMS-induced neuronal reactions in the motor cortex and subsequent their propagation to surrounding cortical areas might change functionally according to task demand when executing and inhibiting a motor response. © 2013 Yamanaka, Kadota and Nozaki. Source


Yamanaka K.,Showa Womens University | Yamanaka K.,University of Tokyo | Yamamoto Y.,University of Tokyo
Clinical Neurophysiology | Year: 2010

Objective: This study aimed to determine the underlying bases of single-trial electroencephalographic (EEG) activities of movement-related potential (MRP) and α-band event-related desynchronisation (α-ERD), both of which are cortical activities related to motor response execution because of their dependence on response time and laterality. Methods: We compared stimulus- and response-triggered EEG power and phase dynamics ipsilateral and contralateral to the response hand in Go trials during visual Go/NoGo reaction time tasks. Results: Two lateralised EEG power and phase dynamics were observed: transient power decreases in α-band EEG (corresponding to α-ERD) and consistent contralateral phase lags of θ-band EEG. Conclusions: α-ERD around the response onset is not substantially reflected in the MRP waveforms mainly because of phase inconsistency. Lateralised MRP waveforms around the response onset are mainly attributed to consistent contralateral phase lags in θ-band additive EEG deflections. Significance: Our results indicate that while both α-ERD and lateralised MRP are related to motor response execution, they reflect separate cortical activities. Analysis of EEG power and phase dynamics can help in elucidating the detailed underlying bases of cortical activities. © 2010 International Federation of Clinical Neurophysiology. Source


Aoki M.,Sanyo | Takao T.,Showa Womens University | Takao K.,Nihon University | Koike F.,Nihon University | Suganuma N.,Kochi University
Tobacco Induced Diseases | Year: 2014

Background: Despite the fact that smokers have deficit in detecting taste, particularly bitter taste, no study has investigated its biological correlate. Methods. In this context, we compared the expression of the bitter taste receptor gene, taste 2 receptor (TAS2R) in the tongues of smokers and non-smokers. Tissue samples were collected from the lateral portion of the tongues of 22 smokers and 22 age- and gender-matched healthy volunteers (19 males and three females) with no history of smoking. Reverse transcriptase-polymerase chain reaction was used to examine the expression of TAS2R in the two groups, and the effect of aging on TAS2R expression was also assessed. Results: TAS2R expression was significantly lower among smokers than non-smokers (t = 6.525, P <.0001, 11.36 ± 6.0 vs. 2.09 ± 2.8, mean ± SD, non-smokers vs. smokers). Further, a positive correlation between age and expression of TAS2R was observed in non-smokers (r =.642, P =.001), but not smokers (r =.124, P =.584). This correlation difference was significant (Z = 1.96, P =.0496). Conclusions: Smokers showed a significantly lower expression of the bitter taste receptor gene than non-smokers, which is potentially caused by their inability to acquire such receptors with age because of cigarette smoking, in contrast to non-smokers. © 2014 Aoki et al.; licensee BioMed Central Ltd. Source

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