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Dive into the research topics where Masamichi Ogawa is active.

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Featured researches published by Masamichi Ogawa.


Clinical Endocrinology | 1999

Mutations in intron 3 of GH-1 gene associated with isolated GH deficiency type II in three Japanese families

Takashi Kamijo; Yoshitaka Hayashi; Akira Shimatsu; Eiichi Kinoshita; Masaaki Yoshimoto; Masamichi Ogawa; Hisao Seo

Isolated GH deficiency (IGHD) type II is a disorder inherited in an autosomal dominant manner. Three mutations at the donor splice site of intron 3 of the GH‐I gene have been identified in five families. In this report, we describe a novel mutation also at the donor splice site of intron 3 in patients with IGHD type II.


The Journal of Pediatrics | 1991

Screening for growth hormone gene deletions in patients with isolated growth hormone deficiency

Takashi Kamijo; John A. Phillips; Masamichi Ogawa; Li-Fang Yuan; Yi-fan Shi; Xiu-lan Bao

2. Cornblath DR, McArthur JC. Predominantly sensory neuropathy in patients with AIDS and AIDS-related complex. Neurology 1988;38:794-6. 3. Cornblath DR, McArthur JC, Kennedy PG, et al. Inflammatory demyelinating peripheral neuropathies associated with human T-cell lyrnphotropic virus type III infection. Ann Neurol 1987;21:32-40. 4. Snider WD, Simpson DM, Neilson G, et al. Neurological complications of acquired immunodeficiency syndrome: analysis of 50 patients. Ann Neurol 1983;14:403-18. 5. McArthur JC, Cohen BA, Seines OA, et al. Low prevalence of neurological and neuropsychological abnormalities in otherwise healthy HIV-l-infected individuals: results from the multicenter AIDS cohort study. Ann Neurol 1989;26: 601-15. 6. Pahwa S, Kaplan M, Fikrig S, et al. Spectrum of human T-cell lymphotropic virus type III infection in children: recognition of symptomatic, asymptomatic, and seronegative patients. JAMA 1986;255:2299-305. 7. Bach M, Bach F. The use of monoclonal anti T-cell antibodies to study T-cell imbalances in human disease. Clin Exp lmmunol 1981;45:449-56. 8. Hart IK, Kennedy PG. Guillain-Barre syndrome associated with cytomegalovirus infection. Q J Med 1988;67:425-30.


Growth Hormone & Igf Research | 1999

Hereditary isolated growth hormone deficiency caused by GH1 gene mutations in Japanese patients

Takashi Kamijo; Yoshitaka Hayashi; Hisao Seo; Masamichi Ogawa

Most patients with hereditary isolated growth hormone deficiency (IGHD) are either heterozygous or homozygous for a growth hormone (GH) gene abnormality. GH1 gene deletions (6.7 and 7.6 kb) from eight Japanese families with IGHD type IA has been detected by Southern blot analysis or polymerase chain reaction and Smal digestion. Heterozygous point mutations at the donor splice site of intron 3 in the GH1 gene have been identified among autosomal dominant IGHD type II patients. Recently, we have identified two kinds of splicing mutations in intron 3 in four Japanese families with IGHD type II. We believe a newly diagnosed G to A mutation at the fifth base of intron 3 in a Japanese family is responsible for the IGHD type II phenotype.


Journal of Pediatric Endocrinology and Metabolism | 2005

Growth hormone releasing hormone receptor (GHRH-R) gene mutation in indian children with familial isolated growth hormone deficiency : A study from western India

Meena P. Desai; Pradnya S. Upadhye; Takashi Kamijo; Michiyo Yamamoto; Masamichi Ogawa; Yoshitaka Hayashi; Hisao Seo; Shilpa R. Nair

BACKGROUND Various mutations of the growth hormone releasing hormone receptor (GHRH-R) gene have been recently described to cause familial isolated growth hormone (GH) deficiency (FIGHD), with the GHRH-R nonsense mutation E72X reported in patients with FIGHD from South Asia. The molecular genetic basis of FIGHD in Indian children is not known. OBJECTIVE To look for the GHRH-R E72X non-sense mutation in our patients with FIGHD and describe its clinical phenotype. PATIENTS AND METHOD A total of 31 patients from 22 families diagnosed 4-20 years previously, 20 patients with familial IGHD-IB from 11 families and 11 patients with non-familial isolated GH deficiency (NFIGHD) (phenotypes IGHD-IB in eight patients and -IA in three) were included. Twenty-eight of 31 patients with IGHD-IB came from two states of Western India, 27 of them Hindus from 18 families (three consanguineous) and one from an inbred Moslem kindred. RESULTS Twenty-two of the patients (71%) (18 FIGHD and four NFIGHD) had a homozygous G-->T transversion in exon 3, with this GHRH-R gene mutation E72X in 90% (18/20) of patients with FIGHD, 36% (4/11) of NFIGHD, altogether 78% (22/28) with phenotype IB. One parent pair with IGHD had homozygous E72X mutation, the rest were heterozygous carriers. Two siblings with IGHD due to homozygous E72X mutation were also heterozygous carriers for GH-1 gene 6.7 kb deletion, inherited from their mother, heterozygous for both GH-1 and GHRH-R mutations. Initial chronological age was 10.89 +/- 3.69 years, bone age 6.4 +/- 3.4 years, and mean height SDS was -5.83 +/- 1.41. The clinical phenotype, with sharp features, lean habitus, lack of frontal bossing or hypoglycemia, was characteristic. The mean peak GH was 1.25 +/- 0.75 ng/ml, IGF-I and IGFBP-3 below -2 SDS with no response to GHRH in those tested. MRI (n = 10) showed pituitary hypoplasia, mean vertical height 2.61 +/- 0.76 mm. Among the other 7/11 NFIGHD patients, four with phenotype IB were negative for genotypes tested in this study; of three patients with phenotype IA, two had the GH-1 gene 6.7 kb deletion, and one was a compound heterozygote with 6.7 and 7.6 kb deletions. CONCLUSIONS The majority of patients with FIGHD from different communities belonged to non-consanguineous Hindu families from Western India. The GHRH-R gene E72X mutation was found in 71% of this series, in 90% of FIGHD, 36% of NFIGHD, and in 78% with phenotype IB. The characteristic phenotype helped in suspecting this mutation. GHRH-R gene mutations may be the most reasonable candidate for IGHD-IB with the E72X mutation predominating in the Indian subcontinent. More extensive studies need to be undertaken.


Clinical Pediatric Endocrinology | 2015

Frequencies of spontaneous breast development and spontaneous menarche in Turner syndrome in Japan.

Toshiaki Tanaka; Yutaka Igarashi; Keiichi Ozono; Kenji Ohyama; Masamichi Ogawa; Hisao Osada; Kazumichi Onigata; Susumu Kanzaki; Hitoshi Kohno; Yoshiki Seino; Hiroaki Takahashi; Toshihiro Tajima; Katsuhiko Tachibana; Hiroyuki Tanaka; Yoshikazu Nishi; Tomonobu Hasegawa; Keinosuke Fujita; Tohru Yorifuji; Reiko Horikawa; Susumu Yokoya

Abstract. The Growject® database on human GH treatment in Turner syndrome was analyzed in the Turner Syndrome Research Collaboration, and the relationships of the frequencies of spontaneous breast development and spontaneous menarche with karyotype and GH treatment were investigated. One hundred and three cases started GH treatment with 0.5 IU/kg/ week (0.5 IU group), and their dose was increased to 0.35 mg/kg/wk midway through the treatment course. Another 109 cases started GH at a dose of 0.35 mg/kg/wk (0.35 mg group). Spontaneous breast development was observed in 77 (36.3%) of the 212 patients, and spontaneous menarche occurred in 31 patients (14.6%). The frequency of spontaneous breast development was significantly lower in patients with the 45,X karyotype and significantly higher in patients with a structural abnormality of the second X chromosome. The frequency of spontaneous menarche was significantly higher in patients with mosaicism characterized by X monosomy and a cellular line with no structural abnormality of the X chromosome. No significant differences in frequencies of spontaneous breast development and spontaneous menarche were observed between the two dose groups, indicating that GH treatment does not increase the frequency of spontaneous puberty.


European Journal of Pediatrics | 1999

A Japanese family with autosomal dominant growth hormone deficiency.

H. Saitoh; T. Fukushima; Tomohiro Kamoda; A. Tanae; Takashi Kamijo; Michiyo Yamamoto; Masamichi Ogawa; Yoshitaka Hayashi; Sachiko Ohmori; Hisao Seo

Abstract We report a 1-year-old Japanese boy and his father with isolated growth hormone deficiency II. In both cases, a G → A transition of the first base of the donor splice site of intron 3 of the growth hormone-1 gene was detected. All unaffected family members were homozygous normal. Conclusion This is the fourth reported case of autosomal isolated growth hormone deficiency II with a G → A transition. The CG dinucleotide at the exon 3-intron 3 junction of the growth hormone-1 gene appears to be a hot spot for point mutations.


Journal of Pediatric Endocrinology and Metabolism | 1997

A CASE OF ISOLATED GROWTH HORMONE (GH) DEFICIENCY WITH COMPOUND HETEROZYGOUS ABNORMALITY AT THE GH-1 GENE LOCUS

Y. Nishi; Masamichi Ogawa; Takashi Kamijo; Y. Igarashi; N. Iwatani; H. Kohno; T. Masumura; Y. Byun; J. Koga

We report a Japanese boy with IGHD who is a compound heterozygote at the GH-1 gene locus. The patient and his mother were heterozygous for a 6.7 kb deletion of the GH-1 gene. A T-->C transition at position -123, an A-->G transition at position -6 and an A-->T transition at position -1 in the GH-1 promoter region and the addition of AGAA at base 250 in intron I were observed in one allele of the patient and his father. These results demonstrate that familial IGHD is a heterogeneous disease that perturbs different steps in the expression of the GH-1 gene.


Acta Paediatrica | 1991

Growth Hormone Secretion and the Therapeutic Effects of Human Growth Hormone: First Japanese Results of the Kabi Pharmacia International Growth Study/International Cooperative Growth Study

Toshiaki Tanaka; Kazuo Shizume; Itsuro Hibi; Kazue Takano; S. Suwa; M. Irie; Y. Okada; Masamichi Ogawa; Akimasa Okuno; K. Kato; H. Kono; M. Sudo; J. Takahara; Kazuo Chihara; Yoshikazu Nishi; K. Hanyu; Katsuhiko Tachibana; T. Hirano; K. Fujieda

Data for a total of 942 new cases of hypopituitarism, out of 3493 patients treated with recombinant human growth hormone (GH) for more than 1 year, have been analysed. The mean peak GH correlated well with clinical variables related to growth and was considered to be a good index of GH secretory capacity. Mean peak GH was correlated inversely with obesity (r= ‐0.253, p < 0.01). The lower the height velocity before treatment, the mean peak GH and the height SDS, the greater was the therapeutic effect achieved. The patients with mean peak GH less than or equal to 5 ng/ml were defined as having complete GH deficiency (GHD), and those with a mean peak GH of 5‐10 ng/ml as having partial GHD. The clinical entity of GH neurosecretory dysfunction could not be identified from either the clinical variables examined or the therapeutic effect. The appearance of GH antibody was considered to be of no clinical significance because its incidence and titre were both low.


Clinical Pediatric Endocrinology | 2012

Favorable Impact of Growth Hormone Treatment on Cholesterol Levels in Turner Syndrome

Hitoshi Kohno; Yutaka Igarashi; Keiichi Ozono; Kenji Ohyama; Masamichi Ogawa; Hisao Osada; Kazumichi Onigata; Susumu Kanzaki; Yoshiki Seino; Hiroaki Takahashi; Toshihiro Tajima; Katsuhiko Tachibana; Hiroyuki Tanaka; Yoshikazu Nishi; Tomonobu Hasegawa; Kenji Fujieda; Keinosuke Fujita; Reiko Horikawa; Susumu Yokoya; Toru Yorifuji; Toshiaki Tanaka

Background: Patients with Turner syndrome (TS) are prone to having metabolic abnormalities, such as obesity, dyslipidemia, hypertension, hyperinsulinemia and type 2 diabetes mellitus, resulting in increased risks of developing atherosclerotic diseases. Objective: To determine the effect of growth hormone (GH) therapy on serum cholesterol levels in prepubertal girls with TS enrolled in the Turner syndrome Research Collaboration (TRC) in Japan. Patients and methods: Eighty-one girls with TS were enrolled in the TRC, and their total cholesterol (TC) levels before GH therapy were compared with reported levels of healthy school-aged Japanese girls. TC levels after 1, 2 and 3 yr of GH treatment were available for 28 of the 81 patients with TS. GH was administered by daily subcutaneous injections, 6 or 7 times/wk, with a weekly dose of 0.35 mg/kg body weight. Results: Baseline TC levels revealed an age-related increase in TS that was in contrast to healthy girls showing unchanged levels. During GH therapy, TC decreased significantly after 1 yr of GH treatment and remained low thereafter. Conclusions: Girls with untreated TS showed an age-related increase in TC that was a striking contrast to healthy girls, who showed unchanged levels. GH therapy in girls with TS brought about a favorable change in TC that indicates the beneficial impact of GH on atherogenic risk.


Acta Paediatrica | 2008

A Highly Sensitive Sandwich Enzyme Immunoassay of Urinary Growth Hormone as a Diagnostic Tool for Growth Hormone Deficiency

H. Tomita; Takashi Kamijo; Osamu Mori; Masamichi Ogawa; E. Ishikawa; Z. Mohri; Yoshiaki Murakami

A total of 41 children with short stature were studied. Their heights were below 2 SD of the mean heights of Japanese boys and girls of their own age groups. They were divided into three groups according to serum peak G H levels in pharmacological tests: 0 up to 5 ngiml, complete G H deficiency (n = 9) between 5 and 10 ng/ml, partial G H deficiency (n = 5) above 10 ng/ml, normal short stature (n = 27). In each subject, both 24-hour and early morning urine specimens were collected. Urinary G H concentration was determined by a highly sensitive sandwich EIA as described previously (1).

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Hitoshi Kohno

Boston Children's Hospital

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Toshiaki Tanaka

Boston Children's Hospital

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