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Featured researches published by Tomokazu Hata.


Pediatric Diabetes | 2011

The relationship between the age of onset of type 1 diabetes and the subsequent development of a severe eating disorder by female patients.

Masato Takii; Yasuko Uchigata; Junji Kishimoto; Chihiro Morita; Tomokazu Hata; Takehiro Nozaki; Keisuke Kawai; Yasuhiko Iwamoto; Nobuyuki Sudo; Chiharu Kubo

Takii M, Uchigata Y, Kishimoto J, Morita C, Hata T, Nozaki T, Kawai K, Iwamoto Y, Sudo N, Kubo C. The relationship between the age of onset of type 1 diabetes and the subsequent development of a severe eating disorder by female patients.


Nutrition & Diabetes | 2014

Higher sleep fragmentation predicts a lower magnitude of weight loss in overweight and obese women participating in a weight-loss intervention

Ryoko Sawamoto; Takehiro Nozaki; Tomokazu Furukawa; Tokusei Tanahashi; Chihiro Morita; Tomokazu Hata; Gen Komaki; Nobuyuki Sudo

Background:Sleep has been identified as having an influence on the success of weight-loss interventions; however, knowledge of the mechanisms and the extent to which sleep disturbances affect the magnitude of weight reduction is inconclusive.Objective:To determine if sleep duration and quality can predict the magnitude of weight reduction in a weight-loss intervention program for overweight and obese women.Methods:Ninety overweight and obese women aged 25–65 years completed the 7-month weight-loss phase of our weight-loss intervention. Sleep duration and quality were evaluated before the intervention by the Pittsburg Sleep Quality Index (PSQI), a self-report questionnaire, and by actigraphy. Serum levels of ghrelin, leptin, cortisol and insulin also were measured at baseline. Insulin resistance was measured by the homeostasis model assessment of insulin resistance (HOMA-IR).Results:The mean reduction rate of body mass index (BMI) after the intervention was 13.6%. Multiple linear regression revealed that the number of wake episodes (WEs) per night had a significant relationship with the reduction of BMI even after adjusting for other clinical variables (β=−0.341, P=0.001). The participants with five or more WEs per night (high-WE group) had a significantly lower reduction in BMI compared with those with fewer than five (normal-WE group), after adjusting for confounding variables. In contrast, the PSQI-assessed parameters, reflecting the subjective assessments of sleep quality and duration, failed to detect an association with the reduction in BMI. Baseline HOMA-IR was significantly higher in the high-WE group than in the normal-WE group after adjusting for confounding variables.Conclusions:Higher sleep fragmentation, as manifested by the increased number of WEs, predicts a lower magnitude of weight reduction in persons participating in weight-loss programs.


Biopsychosocial Medicine | 2011

The longitudinal BMI pattern and body composition of patients with anorexia nervosa who require urgent hospitalization: A case control study

Keisuke Kawai; Sakino Yamashita; Takeharu Yamanaka; Motoharu Gondo; Chihiro Morita; Takehiro Nozaki; Shu Takakura; Tomokazu Hata; Yu Yamada; Sunao Matsubayashi; Masato Takii; Chiharu Kubo; Nobuyuki Sudo

BackgroundThe prevention of serious physical complications in anorexia nervosa (AN) patients is important. The purpose of this study is to clarify which physical and social factors are related to the necessity for urgent hospitalization of anorexia nervosa (AN) patients in a long-term starvation state. We hypothesized that the change of longitudinal BMI, body composition and social background would be useful as an index of the necessity for urgent hospitalization.MethodsAN patients were classified into; urgent hospitalization, due to disturbance of consciousness or difficulty walking(n = 17); planned admission (n = 96); and outpatient treatment only groups (n = 136). The longitudinal BMI pattern and the clinical features of these groups were examined. In the hospitalization groups, comparison was done of body composition variation and the social background, including the educational level and advice from family members.ResultsAfter adjusting for age and duration of illness, the BMI of the urgent hospitalization group was lower than that of the other groups at one year before hospitalization (P < 0.01) and decreased more rapidly (P < 0.01). Urgent hospitalization was associated with the fat free mass (FFM) (P < 0.01). Between the groups, no considerable difference in social factors was found.ConclusionsThe longitudinal pattern of BMI and FFM may be useful for understanding the severity in AN from the viewpoint of failure of the homeostasis system.


PLOS ONE | 2017

Regulation of gut luminal serotonin by commensal microbiota in mice

Tomokazu Hata; Yasunari Asano; Kazufumi Yoshihara; Tae Kimura-Todani; Noriyuki Miyata; Xue Ting Zhang; Shu Takakura; Yuji Aiba; Yasuhiro Koga; Nobuyuki Sudo

Gut lumen serotonin (5-hydroxytryptamine: 5-HT) contributes to several gastrointestinal functions such as peristaltic reflexes. 5-HT is released from enterochromaffin (EC) cells in response to a number of stimuli, including signals from the gut microbiota. However, the specific mechanism by which the gut microbiota regulates 5-HT levels in the gut lumen has not yet been clarified. Our previous work with gnotobiotic mice showed that free catecholamines can be produced by the deconjugation of conjugated catecholamines; hence, we speculated that deconjugation by bacterial enzymes may be one of the mechanisms whereby gut microbes can produce free 5-HT in the gut lumen. In this study, we tested this hypothesis using germ-free (GF) mice and gnotobiotic mice recolonized with specific pathogen-free (SPF) fecal flora (EX-GF). The 5-HT levels in the lumens of the cecum and colon were significantly lower in the GF mice than in the EX-GF mice. Moreover, these levels were rapidly increased, within only 3 days after exposure to SPF microbiota. The majority of 5-HT was in an unconjugated, free form in the EX-GF mice, whereas approximately 50% of the 5-HT was found in the conjugated form in the GF mice. These results further support the current view that the gut microbiota plays a crucial role in promoting the production of biologically active, free 5-HT. The deconjugation of glucuronide-conjugated 5-HT by bacterial enzymes is likely one of the mechanisms contributing to free 5-HT production in the gut lumen.


Eating and Weight Disorders-studies on Anorexia Bulimia and Obesity | 2013

The outcome of Japanese anorexia nervosa patients treated with an inpatient therapy in an internal medicine unit

Naoko Amemiya; Masato Takii; Tomokazu Hata; Chihiro Morita; Shu Takakura; K. Oshikiri; H. Urabe; Shoji Tokunaga; Takehiro Nozaki; Keisuke Kawai; Nobuyuki Sudo; Chiharu Kubo

OBJECTIVE: To investigate the outcome of Japanese anorexia nervosa (AN) patients who were treated with the standard Japanese inpatient therapy. METHOD: Of the 88 female AN patients treated with our inpatient therapy between January 1997 and December 2002, 67 (76.1%) who agreed to cooperate in this study were assessed by the Global Clinical Score (GCS) at admission and follow-up, 6.3±1.8 years after discharge. Their clinical characteristics at admission and discharge were also examined. RESULTS: Four (6.0%) patients had died before follow-up. BMI was significantly increased during inpatient therapy. At follow-up, excellent, much improved, symptomatic, and poor outcomes on GCS were 57.1%, 14.3%, 14.3% and 14.3%, respectively. Younger age at admission and larger BMI at discharge were significantly associated with a better outcome. DISCUSSION: This study shows the potential for the use of this method for the treatment of AN patients in countries without specialized eating disorder units.


Obesity Facts | 2016

Predictors of Dropout by Female Obese Patients Treated with a Group Cognitive Behavioral Therapy to Promote Weight Loss.

Ryoko Sawamoto; Takehiro Nozaki; Tomokazu Furukawa; Tokusei Tanahashi; Chihiro Morita; Tomokazu Hata; Gen Komaki; Nobuyuki Sudo

Objective: To investigate predictors of dropout from a group cognitive behavioral therapy (CBT) intervention for overweight or obese women. Methods: 119 overweight and obese Japanese women aged 25-65 years who attended an outpatient weight loss intervention were followed throughout the 7-month weight loss phase. Somatic characteristics, socioeconomic status, obesity-related diseases, diet and exercise habits, and psychological variables (depression, anxiety, self-esteem, alexithymia, parenting style, perfectionism, and eating attitude) were assessed at baseline. Significant variables, extracted by univariate statistical analysis, were then used as independent variables in a stepwise multiple logistic regression analysis with dropout as the dependent variable. Results: 90 participants completed the weight loss phase, giving a dropout rate of 24.4%. The multiple logistic regression analysis demonstrated that compared to completers the dropouts had significantly stronger body shape concern, tended to not have jobs, perceived their mothers to be less caring, and were more disorganized in temperament. Of all these factors, the best predictor of dropout was shape concern. Conclusion: Shape concern, job condition, parenting care, and organization predicted dropout from the group CBT weight loss intervention for overweight or obese Japanese women.


Obesity science & practice | 2016

A change in objective sleep duration is associated with a change in the serum adiponectin level of women with overweight or obesity undergoing weight loss intervention

Ryoko Sawamoto; Takehiro Nozaki; Tomokazu Furukawa; Tokusei Tanahashi; Chihiro Morita; Tomokazu Hata; Megumi Nakashima; Gen Komaki; Nobuyuki Sudo

Although the serum adiponectin level is inversely correlated to body mass index and closely associated with obesity and related diseases, neither the impact of weight loss on the adiponectin level nor other factors that might influence the adiponectin level during weight loss intervention are well documented.


The Journal of Eating Disorders | 2015

Three cases of appendicitis with anorexia nervosa under inpatient care

Shu Takakura; Hiroaki Yokoyama; Chie Suzuyama; Keita Tatsushima; Makoto Yamashita; Motoharu Gondou; Chihiro Morita; Tomokazu Hata; Masato Takii; Keisuke Kawai; Nobuyuki Sudo

BackgroundLittle is known about the occurrence of appendicitis during the re-nourishment period in anorexia nervosa (AN). We report three cases of appendicitis in patients with AN that occurred after hospitalization for treatment of AN.Case presentationCase 1 is a 34-year-old female, case 2 is a 17-year-old female and case 3 is a 38-year-old female. Constipation was observed in all three cases. Careful management of defecation might be essential to prevent appendicitis among AN patients during the re-nourishment period under inpatient care. In addition, mild and diffuse symptoms were observed in all three cases. Therefore, diagnosis proved to be difficult to make and abdominal computed tomography was particularly helpful in all cases. As the symptoms were diffuse, the condition of appendicitis turned out to be more severe and complicated in one case. Additionally, the incidence of appendicitis in AN in the current study might be higher than that in the normal population.ConclusionsThese findings suggest that appendicitis should be considered as one of the potentially important complications in the therapy for AN.


Biopsychosocial Medicine | 2017

Predictors of successful long-term weight loss maintenance: a two-year follow-up

Ryoko Sawamoto; Takehiro Nozaki; Tomoe Nishihara; Tomokazu Furukawa; Tomokazu Hata; Gen Komaki; Nobuyuki Sudo


Archive | 2018

The Gut Microbiome Derived from Anorexia Nervosa Patients Impairs Weight Gain and Behavioral Performance in Mice

Tomokazu Hata; Noriyuki Miyata; Shu Takakura; Kazufumi Yoshihara; Yasunari Asano; Tae Kimura-Todani; Makoto Yamashita; Xue-Ting Zhang; Natsuru Watanabe; Katsunaka Mikami; Yuji Aiba; Yasuhiro Koga; Nobuyuki Sudo

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Gen Komaki

International University of Health and Welfare

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