Chikako Tomiyama
RMIT University
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Featured researches published by Chikako Tomiyama.
Environmental Health and Preventive Medicine | 2013
Kimie Saito; Hagiko Aoki; Naoshi Fujiwara; Masahiro Goto; Chikako Tomiyama; Yuka Iwasa
ObjectivesResidents who lost land and houses due to disasterous heavy rainfall-related events on July 13, 2004 and the Chuetsu Earthquake on October 23, 2004 were moved to emergency temporary housing. The change in life style due to living under such conditions is assumed to increase oxidative stress level. In this study, we investigated the oxidative stress level in elderly residents of emergency temporary housing, and analyzed its association with lifestyle and body composition following these disasters.MethodsA noninvasive oxidative stress marker, urinary 8-hydroxydeoxyguanosine (8-OHdG), and body composition were measured in 73 elderly residents of emergency temporary housing.ResultsIn the elderly female residents, the urinary 8-OHdG level tended to decrease with time after the disasters. 8-OHdG levels were slightly higher in females than males and significantly higher among those who exercised regularly compared to those who did not, particularly in females. A weak correlation was noted between the urinary 8-OHdG level and muscle ratio in females.ConclusionsThe in vivo oxidative stress level in our study cohort of elderly residents of emergency temporary housing changed following the change in life style, but remained within the normal range. The increase in oxidative stress levels of elderly females was related to menopause. A decrease in estrogen levels due to menopause inhibits its antioxidant effects, which increases 8-OHdG levels. Although it is difficult to determine, a decrease in daily stressors over time following the disaster could be a cause of the decrease in oxidative stress levels. We suggest that the close evaluation of the stress level of disaster victims is desirable, in combination with evidence of antioxidative substances and the psychosocial influence of suffering as a consequence of the disaster.
Clinical and Experimental Immunology | 2011
Chikako Tomiyama; Hisami Watanabe; Y. Izutsu; Mayumi Watanabe; Toru Abo
Concanavalin A (Con A)‐induced hepatitis is a mouse model of acute autoimmune hepatitis. The aim of this study was to investigate the role of hepatic dendritic cells (DC) in the immune modulation of tissue damage. Almost all hepatic DC were plasmacytoid DC (CD11c+ I‐Alow B220+); however, conventional DC were CD11c+ I‐Ahigh B220–. At an early stage (3–6 h) after Con A administration, the number of DC in both the liver and spleen decreased, increasing thereafter (12–24 h) in parallel with hepatic failure. The hepatic CD11c+ DC population contained many CD11b‐ cells, while the majority of splenic CD11c+ DC were CD11b+. After Con A administration, the proportion of I‐A+ and CD11b+ cells within the CD11c+ DC population tended to increase in the liver, but not in the spleen. Similarly, expression of the activation markers CD80, CD86 and CD40 by CD11c+ DC increased in the liver, but not in the spleen. Next, adoptive transfer of DC isolated from the liver and spleen was performed 3 h after Con A administration to examine the immunomodulatory function of DC. Only hepatic DC had the ability to suppress hepatic failure. Analysis of cytokine production and subsequent identification of the effector cells showed that hepatic DC achieved this by suppressing the production of interleukin (IL)‐12 and IL‐2, rather than modulating effector cell function.
Acupuncture in Medicine | 2015
Mayumi Watanabe; Eisuke Kainuma; Chikako Tomiyama
Objective To study the effects of repetitive manual acupuncture treatment on acute stress in mice and to explore its impact on the immune system. Methods Thirty-six mice were randomly allocated to one of four groups: control, acupuncture, stress and acupuncture+stress (n=9 each). Mice in the two acupuncture groups were given daily acupuncture treatment superficially (to skin depth) at CV6, CV12 and bilateral ST25, LR14, GB20, GB21, BL10, BL11, BL13, BL14, BL19, BL23 and BL25 for 7 days. On the eighth day mice in the stress and acupuncture+stress groups were exposed to acute stress for 2 h by confinement in a 50 mL centrifuge tube. Body temperature, blood glucose, the number and subpopulation ratios of leucocytes in the liver, spleen and thymus, natural killer (NK) cell percentage cytotoxicity and serum corticosterone and interferon gamma IFNγ were quantified. Results Mice exposed to stress (irrespective of acupuncture treatment) exhibited hypothermia and hyperglycaemia. However, the increase in glucose level was mitigated by repetitive acupuncture treatment (p<0.05). Percentage cytotoxicity and the level of corticosterone were significantly increased after stress but were unaffected by acupuncture. IFNγ levels did not differ between the groups. Hepatic innate immunity in the liver appeared to be stimulated by repetitive acupuncture treatment as proportions of extrathymic T cells, NK cells and NKT cells in the liver were greatest in the acupuncture+stress group and significantly increased relative to the control group. Conclusions Repetitive manual acupuncture mitigated stress-induced hyperglycaemia and enhanced markers of innate immunity in the liver within the range of normal homoeostasis. As long as acupuncture stimuli were appropriately applied, they did not appear to be stressful to the mice.
Biomedical Research-tokyo | 2015
Chikako Tomiyama; Mayumi Watanabe; Takashi Honma; Akihiro Inada; Takayoshi Hayakawa; Masae Ryufuku; Toru Abo
The effect of repetitive mild hyperthermia on body temperature, the autonomic nervous system, and innate and adaptive immunity was investigated using a new hyperthermia treatment system, nanomist sauna (NMS). Six healthy volunteers participated and the concentration of catecholamines and cortisol, and the frequency and function of leukocytes in the peripheral blood were investigated before and after successive 7 days of hyperthermia treatment (20 min/day, 40°C, 100% relative humidity). After treatment, the blood level of adrenaline and cortisol on the 7th day was decreased compared with the 1st day, indicating the suppression of the sympathetic nervous system activity. Moreover, the frequency of CD56(+)NK, CD56(+)NKT and B cells on the 7th day tended to be increased compared with the 1st day. The frequency of HLA-DR-positive NK and NKT cells and expression of HLA-DR on B and T cells increased. The cytotoxicity of NK cells and proliferative response of B cells were also elevated. The results indicate that repetitive mild hyperthermia treatment might suppress excessive sympathetic dominance and modify immunity. Additionally, because it can provide the same effects as conventional hyperthermia treatments with minimal burden to the body, NMS may be a novel patient- and elderly-friendly hyperthermia treatment for health promotion.
Medical Hypotheses | 2014
Toru Abo; Mayumi Watanabe; Chikako Tomiyama; Yasuhiro Kanda
Capillary vessel flow in the base of the fingernail can be observed by microscopy. This flow is switched off under some conditions, such as coldness, surprise, and anger and is switched on again under other conditions, such as warming, relaxation, and mild exercise. In other words, capillary vessels perform two functions: switching flow on and off. It is speculated that the switch-off function is necessary to direct energy production to the glycolysis pathway, while the switch-on function is necessary for the mitochondrial pathway. This is because glycolysis takes place under anaerobic conditions, while oxidative phosphorylation in the mitochondria proceeds under aerobic conditions in the body. To switch off circulation, the negative electric charges on the surface of erythrocytes and the capillary wall may be decreased by stimulation of the sympathetic nerves and secretion of steroid hormones. Negative charge usually acts as repulsive force between erythrocytes and between erythrocytes and the capillary wall. By decreasing the negative charge, erythrocytes can aggregate and also adhere to the capillary wall. These behaviors may be related to the capillary flow switch-off function. Here, it is emphasized that the capillary vessels possess not only a switch-on function but also a switch-off function for circulation.
Hepato-gastroenterology | 2013
Yoshinobu Sato; Chikako Tomiyama; Satoshi Yamamoto; H. Oya; T. Kobayashi; H. Kokai; Kohei Miura; Hirose Y; K. Hatakeyama
BACKGROUND/AIMS Liver cirrhotic patients are immunological compromised hosts. Preoperative status in cirrhotic patients affects postoperative infection complications. This study investigates the perioperative immunological changes in the differentiation by MELD score. METHODOLOGY Fifteen patients underwent LDLT and were divided two groups, Group I (n=5, MELD score >=20) and Group II (n=10, MELD score <20). Immunological status of cirrhotic patients was analyzed for Th1, Th2, Treg and Th17 by flow cytometry using monoclonal antibody CD3/CD19,CD4/8, FoxP3, IL-17, IFN-γ and TNF-α. RESULTS T cell decreased and increased gradually following LDLT. The preoperative T cell count of MELD score 33 patients was very low. CD4 and CD8 T cells also decreased after LDLT. The preoperative CD8+ T cell count of MELD score 33 patients was very low. Th17 decreased and recovered gradually in the all patients after LDLT. However Th17 of MELD score 33 did not recover. IFN-γ-producing cells in naive T cells decreased after LDLT. Preoperatively those in the Group I was lower than those in the Group II. The population of Treg decreased in the Group I, however, it increased in the Group II on 7 days after LDLT. CONCLUSIONS The patients with MELD score >20 showed a decrease of cytotoxic immunity with both diminution and delay of CD8+ T cells and Th17 helper T cells. The cytotoxic immunity of the patients with MELD score <20 was maintained and recovered in the early period after LDLT. The patients with MELD score >20 might be at high risk of infection after LDLT.
Biomedical Research-tokyo | 2011
Hanaa Y. Bakir; Chikako Tomiyama; Toru Abo
Biomedical Research-tokyo | 2014
Yuiko Aso-Ishimoto; Satoshi Yamagiwa; Takafumi Ichida; Ryoko Miyakawa; Chikako Tomiyama; Yoshinobu Sato; Hisami Watanabe; Yutaka Aoyagi
Health | 2012
Mayumi Watanabe; Osamu Takano; Chikako Tomiyama; Hiroaki Matsumoto; Nobuatsu Urahigashi; Eisuke Kainuma; Takeo Madarame; Minoru Fukuda; Toru Abo
Health | 2013
Mayumi Watanabe; Osamu Takano; Chikako Tomiyama; Jianjun Guan; Guanhui Hou; Hidetoshi Mori; Kazushi Nishijo; Toru Abo; Kohei Akazawa