Based on the stochastic inclined rods model proposed by H. Matsuura et al., we study the motion of actin myosin system in an overdamped regime. Our model is composed ofan inclined spring (rod), a myosin head and a myo...Based on the stochastic inclined rods model proposed by H. Matsuura et al., we study the motion of actin myosin system in an overdamped regime. Our model is composed ofan inclined spring (rod), a myosin head and a myosin filament. The results of calculation show that the modelcan convert the random motion to one-directional motion, and the myosin head works as a resonator of random noise, which absorbs the energy through a stochastic resonance. The results show that the inclined rod and the intermolecular potential are very important for the system to move.展开更多
The number of older adults （individuals ≥65 years）, particularly women, in our society is increasing and understanding the impact of exercise on muscle capacity （e.g., strength and power） and subsequently physica...The number of older adults （individuals ≥65 years）, particularly women, in our society is increasing and understanding the impact of exercise on muscle capacity （e.g., strength and power） and subsequently physical function is of utmost importance to prevent disability and maintain independence. Muscle capacity declines with age and this change negatively impacts physical function in older women. Exercise, specifically resistance training, is recommended to counteract these declines; however, the synergistic relationships between exercise, muscle capacity, and physical function are poorly understood. This review will summarize the literature regarding age-related changes in the aforementioned variables and review the research on the impact of resistance training interventions on muscle capacity and physical function in older women. Recommendations for future research in this area will be discussed.展开更多
Mitochondrial dysfunction in aged skeletal muscle has been mainly attributable to mtDNA deletions, uncoupling in oxidative phosphorylation, leading to ATP deficit. Moreover, the accumulation of damaged mitochondria is...Mitochondrial dysfunction in aged skeletal muscle has been mainly attributable to mtDNA deletions, uncoupling in oxidative phosphorylation, leading to ATP deficit. Moreover, the accumulation of damaged mitochondria is associated with imperfect autophagocytosis and declined biogenesis of efficient mitochondria. Mitochondria-associated apoptotic signaling is involved in the loss of fibers and atrophy of the remaining fibers by ROS, TNF-α, and denervation, leading to sarcopenia. Current investigations have indicated that exercise, especially resistance exercise, has extensively preventive effects on sarcopenia. Whether caloric restriction in aged animals is suitable for aged people remains to be further clinlically experimented. Additionally, it will be interesting to develop effectively supplementary and alternative medical methods associated with Chinese tonifying herbs to prevent or reverse sarcopenia in the future because of their efficacy and less frequent side effects.展开更多
The syndrome of femoral adductors is a common disorder of the sport injury. It is manifested by pain in the pubic and medial femoral regions, which is exacerbated by walking and squatting down. The author had treated ...The syndrome of femoral adductors is a common disorder of the sport injury. It is manifested by pain in the pubic and medial femoral regions, which is exacerbated by walking and squatting down. The author had treated 32 cases of the syndrome by electroacupuncture and moxibustion with satisfactory therapeutic results as reported in the following.展开更多
Purpose： Macrophages are known to be important for healing numerous injured tissues depending on their functional phenotypes in response to different stimuli. The objective of this study was to reveal macrophage phen...Purpose： Macrophages are known to be important for healing numerous injured tissues depending on their functional phenotypes in response to different stimuli. The objective of this study was to reveal macrophage phenotypic changes involved in exercise-induced skeletal muscle injury and regeneration. Methods： Adult male Sprague-Dawley rats experienced one session of downhill running （16~ decline, 16 m/min） for 90 min. After exercise the blood and soleus muscles were collected at 0 h, 6 h, 12 h, 1 d, 2 d, 3 d, 1 w and 2 w after exercise, separately. Results： It was showed that CD6B＋ M1 macrophages mainly infiltrated into musc｜e necrotic sites at 1-3 d, while CD163＋ M2 macrophages were present in muscles from 0 h to 2 weeks after exercise. Using transmission electron microscopy, we observed activated satellite cells 1 d after exercise. Thl-associated transcripts of iNOS and Cc12 were inhibited post exercise, while COX-2 mRNA was dramatically increased 12 h after running （p 〈 0.01 ）. M2 phenotype marker Arg-1 increased 12 h and 3 d （p 〈 0.05, p 〈 0.01 ） after exercise, and Clecl0a and Mrc2 were up-regulated in muscles 12 h following exercise （p 〈 0.05, p 〈 0.05）. Conclusion： The data demonstrate the dynamic patterns of macrophage phenotype in skeletal muscle upon eccentric exercise stimuli, and M1 and M2 phenotypes perform different functions during exercise- induced skeletal muscle injury and recovery.展开更多
The afferent arteriole （AA） of rat kidney exhibits the myogenic response, in which the vessel constricts in response to an elevation in blood pressure and dilates in response to a pressure reduction. Additionally, t...The afferent arteriole （AA） of rat kidney exhibits the myogenic response, in which the vessel constricts in response to an elevation in blood pressure and dilates in response to a pressure reduction. Additionally, the AA exhibits spontaneous oscillations in vascular tone at physiological luminal pressures. These time-periodic oscillations stem from the dynamic exchange of Ca^2＋ between the cytosol and the sarcoplasmie reticulum, cou- pled to the stimulation of Ca^2＋-activated potassium and chloride channels, and to the modulation of voltage-gated L-type Ca^2＋ channels. The effects of physiological factors, including blood pressure and vasoactive substances, on AA vasomotion remain to be well characterized. In this paper, we analyze a mathematical model of Ca^2＋ signaling in an AA smooth muscle cell. The model represents detailed transmembrane ionic trans- port, intracellular Ca^2＋ dynamics as well as kinetics of nitric oxide （NO） and superoxide （O2^-） formation, diffusion and reaction. NO is an important factor in the maintenance of blood pressure and O2^- has been shown to contribute significantly to the functional alternations of blood vessels in hypertension. We perform a bifurcation analysis of the model equations to assess the effect of luminal pressure, NO and O2^- on the behaviors of limit cycle oscillations.展开更多
Exploration and activity are often described as trade-offs between the fitness benefits of gathering information and resources, and the potential costs of increasing exposure to predators and para- sites. More explora...Exploration and activity are often described as trade-offs between the fitness benefits of gathering information and resources, and the potential costs of increasing exposure to predators and para- sites. More exploratory individuals are predicted to have higher rates of parasitism, but this relationship has rarely been examined for virus infections in wild populations. Here, we used the multimammate mouse Mastomys natalensis to investigate the relationship between exploration, activity, and infection with Morogoro virus （MORV）. We characterized individual exploratory behav- ior （open field and novel object tests） and activity （trap diversity）, and quantified the relationship between these traits and infection status using linear regression. We found that M. natalensis expresses consistent individual differences, or personality types, in exploratory behavior （repeat- ability of 0.30, 95% CI： 0.21-0.36）. In addition, we found a significant contrasting effect of age on ex- ploration and activity where juveniles display higher exploration levels than adults, but lower field- activity. There was however no statistical evidence for a behavioral syndrome between these 2 traits. Contrary to our expectations, we found no correlation between MORV infection status and exploratory behavior or activity, which suggests that these behaviors may not increase exposure probability to MORV infection. This would further imply that variation in viral infection between individuals is not affected by between-individual variation in exploration and activity.展开更多
文摘Based on the stochastic inclined rods model proposed by H. Matsuura et al., we study the motion of actin myosin system in an overdamped regime. Our model is composed ofan inclined spring (rod), a myosin head and a myosin filament. The results of calculation show that the modelcan convert the random motion to one-directional motion, and the myosin head works as a resonator of random noise, which absorbs the energy through a stochastic resonance. The results show that the inclined rod and the intermolecular potential are very important for the system to move.
文摘The number of older adults （individuals ≥65 years）, particularly women, in our society is increasing and understanding the impact of exercise on muscle capacity （e.g., strength and power） and subsequently physical function is of utmost importance to prevent disability and maintain independence. Muscle capacity declines with age and this change negatively impacts physical function in older women. Exercise, specifically resistance training, is recommended to counteract these declines; however, the synergistic relationships between exercise, muscle capacity, and physical function are poorly understood. This review will summarize the literature regarding age-related changes in the aforementioned variables and review the research on the impact of resistance training interventions on muscle capacity and physical function in older women. Recommendations for future research in this area will be discussed.
文摘Mitochondrial dysfunction in aged skeletal muscle has been mainly attributable to mtDNA deletions, uncoupling in oxidative phosphorylation, leading to ATP deficit. Moreover, the accumulation of damaged mitochondria is associated with imperfect autophagocytosis and declined biogenesis of efficient mitochondria. Mitochondria-associated apoptotic signaling is involved in the loss of fibers and atrophy of the remaining fibers by ROS, TNF-α, and denervation, leading to sarcopenia. Current investigations have indicated that exercise, especially resistance exercise, has extensively preventive effects on sarcopenia. Whether caloric restriction in aged animals is suitable for aged people remains to be further clinlically experimented. Additionally, it will be interesting to develop effectively supplementary and alternative medical methods associated with Chinese tonifying herbs to prevent or reverse sarcopenia in the future because of their efficacy and less frequent side effects.
文摘The syndrome of femoral adductors is a common disorder of the sport injury. It is manifested by pain in the pubic and medial femoral regions, which is exacerbated by walking and squatting down. The author had treated 32 cases of the syndrome by electroacupuncture and moxibustion with satisfactory therapeutic results as reported in the following.
文摘Purpose： Macrophages are known to be important for healing numerous injured tissues depending on their functional phenotypes in response to different stimuli. The objective of this study was to reveal macrophage phenotypic changes involved in exercise-induced skeletal muscle injury and regeneration. Methods： Adult male Sprague-Dawley rats experienced one session of downhill running （16~ decline, 16 m/min） for 90 min. After exercise the blood and soleus muscles were collected at 0 h, 6 h, 12 h, 1 d, 2 d, 3 d, 1 w and 2 w after exercise, separately. Results： It was showed that CD6B＋ M1 macrophages mainly infiltrated into musc｜e necrotic sites at 1-3 d, while CD163＋ M2 macrophages were present in muscles from 0 h to 2 weeks after exercise. Using transmission electron microscopy, we observed activated satellite cells 1 d after exercise. Thl-associated transcripts of iNOS and Cc12 were inhibited post exercise, while COX-2 mRNA was dramatically increased 12 h after running （p 〈 0.01 ）. M2 phenotype marker Arg-1 increased 12 h and 3 d （p 〈 0.05, p 〈 0.01 ） after exercise, and Clecl0a and Mrc2 were up-regulated in muscles 12 h following exercise （p 〈 0.05, p 〈 0.05）. Conclusion： The data demonstrate the dynamic patterns of macrophage phenotype in skeletal muscle upon eccentric exercise stimuli, and M1 and M2 phenotypes perform different functions during exercise- induced skeletal muscle injury and recovery.
文摘The afferent arteriole （AA） of rat kidney exhibits the myogenic response, in which the vessel constricts in response to an elevation in blood pressure and dilates in response to a pressure reduction. Additionally, the AA exhibits spontaneous oscillations in vascular tone at physiological luminal pressures. These time-periodic oscillations stem from the dynamic exchange of Ca^2＋ between the cytosol and the sarcoplasmie reticulum, cou- pled to the stimulation of Ca^2＋-activated potassium and chloride channels, and to the modulation of voltage-gated L-type Ca^2＋ channels. The effects of physiological factors, including blood pressure and vasoactive substances, on AA vasomotion remain to be well characterized. In this paper, we analyze a mathematical model of Ca^2＋ signaling in an AA smooth muscle cell. The model represents detailed transmembrane ionic trans- port, intracellular Ca^2＋ dynamics as well as kinetics of nitric oxide （NO） and superoxide （O2^-） formation, diffusion and reaction. NO is an important factor in the maintenance of blood pressure and O2^- has been shown to contribute significantly to the functional alternations of blood vessels in hypertension. We perform a bifurcation analysis of the model equations to assess the effect of luminal pressure, NO and O2^- on the behaviors of limit cycle oscillations.
文摘Exploration and activity are often described as trade-offs between the fitness benefits of gathering information and resources, and the potential costs of increasing exposure to predators and para- sites. More exploratory individuals are predicted to have higher rates of parasitism, but this relationship has rarely been examined for virus infections in wild populations. Here, we used the multimammate mouse Mastomys natalensis to investigate the relationship between exploration, activity, and infection with Morogoro virus （MORV）. We characterized individual exploratory behav- ior （open field and novel object tests） and activity （trap diversity）, and quantified the relationship between these traits and infection status using linear regression. We found that M. natalensis expresses consistent individual differences, or personality types, in exploratory behavior （repeat- ability of 0.30, 95% CI： 0.21-0.36）. In addition, we found a significant contrasting effect of age on ex- ploration and activity where juveniles display higher exploration levels than adults, but lower field- activity. There was however no statistical evidence for a behavioral syndrome between these 2 traits. Contrary to our expectations, we found no correlation between MORV infection status and exploratory behavior or activity, which suggests that these behaviors may not increase exposure probability to MORV infection. This would further imply that variation in viral infection between individuals is not affected by between-individual variation in exploration and activity.
