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Dive into the research topics where Hiroaki Ohta is active.

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Featured researches published by Hiroaki Ohta.


Journal of Bone and Mineral Metabolism | 2013

Guidelines for the use of bone metabolic markers in the diagnosis and treatment of osteoporosis (2012 edition)

Yoshiki Nishizawa; Hiroaki Ohta; Masakazu Miura; Masaaki Inaba; Schoichi Ichimura; Masataka Shiraki; Junichi Takada; Osamu Chaki; Hiroshi Hagino; Saeko Fujiwara; Masao Fukunaga; Takami Miki; Noriko Yoshimura

Recently the clinical application of bone metabolic markers has achieved significant progress and the measurements of these indices give us a better understanding of the pathogenesis of osteoporosis. Bone metabolic markers were adapted to select drug treatment for osteoporosis and to evaluate drug efficacy. Therefore, the proper application and assessment of bone metabolic markers in clinical practice is very important. To achieve these aims, the committee on the guidelines for the use of biochemical markers of bone turnover in osteoporosis authorized by the Japan Osteoporosis Society has summarized recent progress in bone markers and proposed the proper utilization of bone markers. Although the use of bone metabolic markers now has an important role in the daily management of osteoporosis, their use in Japan is still insufficient because of insurance coverage limitations. Since the Japan Osteoporosis Society first created the 2001 guidelines, new bone metabolic markers have been introduced into clinical practice. The availability of new osteoporosis treatments that promote bone formation has changed the clinical application of bone metabolic markers in current practice. Therefore, revisions to the current clinical practice are needed which led to the proposal to create these new 2012 guidelines.


Journal of Cellular Physiology | 2010

Cells of Extraembryonic Mesodermal Origin Confer Human Dystrophin in the Mdx Model of Duchenne Muscular Dystrophy

Yayoi Kawamichi; Chang-Hao Cui; Masashi Toyoda; Hatsune Makino; Akane Horie; Yoriko Takahashi; Kenji Matsumoto; Hirohisa Saito; Hiroaki Ohta; Kayoko Saito; Akihiro Umezawa

Duchenne muscular dystrophy is an X‐linked recessive genetic disease characterized by severe skeletal muscular degeneration. The placenta is considered to be a promising candidate cell source for cellular therapeutics because it contains a large number of cells and heterogenous cell populations with myogenic potentials. We analyzed the myogenic potential of cells obtained from six parts of the placenta, that is, umbilical cord, amniotic epithelium, amniotic mesoderm, chorionic plate, villous chorion, and decidua basalis. In vitro cells derived from amniotic mesoderm, chorionic plate, and villous chorion efficiently transdifferentiate into myotubes. In addition, in vivo implantation of placenta‐derived cells into dystrophic muscles of immunodeficient mdx mice restored sarcolemmal expression of human dystrophin. Differential contribution to myogenesis in this study may be attributed to placental portion‐dependent default cell state. Molecular taxonomic characterization of placenta‐derived maternal and fetal cells in vitro will help determine the feasibility of cell‐based therapy. J. Cell. Physiol. 223:695–702, 2010.


Current Medical Research and Opinion | 2016

Lack of cooperation between physicians and dentists during osteoporosis treatment may increase fractures and osteonecrosis of the jaw

Akira Taguchi; Masataka Shiraki; Toshitsugu Sugimoto; Hiroaki Ohta; Satoshi Soen

Abstract Objective: Our previous questionnaire-based survey suggested that discontinuation of antiresorptive agents before tooth extraction may increase adverse events and disturb osteoporosis treatment without completely preventing osteonecrosis of the jaw (O.N.J.). We also found little cooperation between physicians and dentists in Japan. However, limitations of our previous study included a survey of doctors belonging to small clinics and a small sample size. Our current study aimed to confirm the results of our previous survey in doctors mainly belonging to academia. Methods: A structured questionnaire including 14 key clinical queries was sent to 1812 physicians of the Japan Osteoporosis Society, and 629 responses were received. Results: Dentists requested discontinuation of many medications that were not associated with the incidence of O.N.J. A total of 523 respondents had received discontinuation requests from dentists. Of these, 97 respondents experienced 119 adverse events including 25 fractures and seven incidences of O.N.J. The ratios of valid responses for fractures were 3.6% and 5.3% in patients with a discontinuation of <3 and ≥3 months, respectively. Those for O.N.J. were 0.7% and 1.6%, respectively. Respondents who refused discontinuation requests reported no cases of O.N.J. Approximately 17% of respondents had patients who discontinued osteoporosis treatment following a requested drug discontinuation after tooth extraction. Approximately 62% of respondents did not request oral health care by a dentist before antiresorptive therapy, and 72% reported no cooperation between physicians and dentists in their region. Conclusions: This study reconfirms the results of our previous survey. Discontinuation of antiresorptive treatment may increase both fractures and O.N.J. Immediate development of a strategy for sharing information about O.N.J. among physicians, dentists, and patients is required to reduce the incidence of both O.N.J. and skeletal events in osteoporosis treatment. Study limitations were selection bias due to low response rate and possible inaccurate responses to the questionnaire.


Obstetrics & Gynecology | 2004

Uterine cervical diverticulum resembling a degenerated leiomyoma.

Izumi Umezaki; Koichiro Takagi; Motohiko Aiba; Hiroaki Ohta

BACKGROUND: Uterine diverticulum is a very rare anomaly. Most previously reported cases were called “pregnancy-associated sacculations,” and only 2 cases were considered true uterine diverticula. CASE: A 41-year-old woman presented with fever and lower abdominal pain. An extrauterine mass was detected, and a hysterectomy was performed. Pathological examination revealed a cystic uterine diverticulum lined with cervical glands and myometrium arising from the cervix. The final diagnosis was an infected uterine cervical diverticulum. CONCLUSION: Cervical diverticulum is a rare lesion that should be added to the differential diagnosis of a woman presenting with a pelvic mass.


Scientific Reports | 2015

Sexual Satisfaction of infertile couples assessed using the Golombok-Rust Inventory of Sexual Satisfaction (GRISS)

Mayumi Shoji; Toshio Hamatani; Shoko Ishikawa; Naoaki Kuji; Hiroaki Ohta; Hideo Matsui; Yasunori Yoshimura

Recently, infertility treatment-related psychological effects are receiving increased attention. However, whether sexual satisfaction is reduced amongst infertile couples remains to be elucidated. In this study, sexual satisfaction of Japanese infertile couples was assessed using a validated questionnaire designed to assess the male and female partner individually, and the couple as a whole for the first time. This study randomly included 170 infertile couples seen at the outpatient clinic and 170 couples that had recently achieved spontaneous pregnancy. All couples were given the Japanese version of the Golombok-Rust Inventory of Sexual Satisfaction (GRISS). In couples aged 35 years or older, the male partners showed significantly worse sexual satisfaction scores than the female partners. Sexual satisfaction also deteriorated with therapeutic interventions, with mental factors affected more than physical factors. Therapeutic interventions such as timed sexual intercourse and assisted reproductive technology were considered emotionally stressful for infertile couples, with sexual satisfaction accordingly lower in this group than in couples achieving spontaneous pregnancy. GRISS successfully evaluated lower sexual satisfaction associated with infertility, and hence is a useful tool for identifying couples whose sexual satisfaction could be enhanced by counselling or other stress-reduction modalities.


Journal of Bone and Mineral Metabolism | 2017

Decreased rate of hip fracture and consequent reduction in estimated medical costs in Japan

Hiroaki Ohta; Mitsuko Mouri; Tatsuhiko Kuroda; Toshitaka Nakamura; Masataka Shiraki; Hajime Orimo

The frequency of hip fractures associated with aging of the population is declining in many countries. Even in Japan, where this frequency has been increasing continually, a shift to decreasing frequency has been noted in recent reports. The objective of this study was to investigate the effects of this decrease and to estimate the number of hip fracture patients and the resulting reduction in national medical care expenditures. The differences in the number of patients were estimated by multiplying the population for each sex and each age group by the fracture rates before the decrease (2007) and after the decrease (2012). Total reduced cost was calculated by multiplying the treatment cost required for hip fracture and the annual medical cost of nursing care. The estimated number of hip fracture patients decreased by approximately 4000 in the elderly female population, and the resulting reduction in medical costs was approximately US


Fetal Diagnosis and Therapy | 2003

A Case of Fetal Subdural Hematoma at 31 Weeks of Gestation in a Woman on Warfarin Therapy after Cabrol’s Operation

Yoshio Matsuda; Kazunari Hashiguchi; Yoshika Akizawa; Rie Saito; Hiroaki Ohta

280 million. The number of patients with hip fractures has decreased in elderly Japanese women; as a result, the medical costs for treatment and nursing care might decrease.


Brain & Development | 2013

Enhanced expression of myogenic differentiation factors and skeletal muscle proteins in human amnion-derived cells via the forced expression of MYOD1

Yoshika Akizawa; Hitoshi Kanno; Yayoi Kawamichi; Yoshio Matsuda; Hiroaki Ohta; Hisaichi Fujii; Hideo Matsui; Kayoko Saito

The case of a complicated pregnancy of a woman who had undergone Cabrol’s operation, and whose baby suffered from subdural hematoma is presented. Although the outcome of this case was not so severe, we would like to inform about the risk to both the mother and her fetus as a result of serious complications.


Osteoporosis and sarcopenia | 2016

Recent nutritional trends of calcium and vitamin D in East Asia

Hiroaki Ohta; Kazuhiro Uenishi; Masataka Shiraki

OBJECTIVES Mesenchymal stem cells are expected to be an ideal cell source for cellular and gene therapy. We previously showed that cells derived from the human placenta can be induced to differentiate into myotubes in vitro and to express dystrophin in mdx/scid mice in vivo. In this study, we examined whether amnion-derived cells can be efficiently transduced and differentiated using lentiviral vectors carrying human MYOD1. METHODS The amnion-derived cells were isolated from human preterm placentas. They were transduced with the MYOD1 vector, and mRNA levels for MYOD1, MYF5, MYOG, MYH2 and DMD were determined by quantitative-reverse transcriptase-polymerase chain reaction, and also examined immunocytochemically. RESULTS Approximately 70% of amnion-derived cells were efficiently transduced by the lentiviral vectors. MYOD1 activates MYF5 and MYOG, MYH2 and DMD after a 7-day culture. The concerted upregulations of these myogenic regulatory factors enhanced MYH2 and DMD expressions. PAX7 was below the detectable level. Both myosin heavy chain and dystrophin were demonstrated by immunocytochemistry. CONCLUSIONS MYOD1 activates MYF5 and MYOG, the transcription factor genes essential for myogenic differentiation, and the concerted upregulation of these myogenic regulatory factors enhanced MYH2 and DMD expressions. The amniotic membrane is an immune-privileged tissue, making MYOD1-transduced amnion-derived cells an ideal cell source for cellular and gene therapy for muscle disorders. This is the first report showing that amnion-derived cells can be modified by exogenous genes using lentiviral vectors. Furthermore, MYOD1-transduced amnion-derived cells are capable of the dystrophin expression necessary for myogenic differentiation.


Microbiology and Immunology | 2008

Diagnosis of toxic shock syndrome by two different systems : clinical criteria and monitoring of TSST-1-reactive T cells

Yoshio Matsuda; Hidehito Kato; Erina Ono; Ken Kikuchi; Mitsue Muraoka; Koichiro Takagi; Ken'ichi Imanishi; Shun'ichi Itoh; Tatsuo Itoh; Tetsuya Ogawa; Kosaku Nitta; Sayaka Inokuchi; Toshifumi Hibi; Hiroaki Ohta; Takehiko Uchiyama

Calcium intake may play an important role on bone health. The recent national nutritional survey in Japan revealed the gradual decrease in calcium intake to around 480 mg/day. In addition, the patients with low level of vitamin D become too large in proportion. The present perspective proposes to increase calcium intake in Asian population.

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Hajime Orimo

Health Science University

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Toshitaka Nakamura

University of Occupational and Environmental Health Japan

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Akira Taguchi

Matsumoto Dental University

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Yoshio Matsuda

International University of Health and Welfare

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