Hiroshi Aizawa
Jikei University School of Medicine
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Featured researches published by Hiroshi Aizawa.
Journal of Dermatology | 1995
Hiroshi Aizawa; Michihito Niimura
The purpose of this study was to measure the serum levels of IGF‐1 in women with postadolescent acne compared to normal controls, and evaluate the relationship of these levels to the levels of androgens, in order to investigate the possible role of IGF‐1 in the pathogenesis of acne. Eighty‐two female patients with acne between 20 and 25 years of age and thirty‐one age‐matched control women were studied. We measured the serum levels of total testosterone (T), free testosterone (FT), dihydrotestosterone (DHT), dehydroepiandrosterone sulfate (DHEA‐S), and insulin‐like growth factor‐1 (IGF‐1).
Journal of Dermatology | 1996
Hiroshi Aizawa; Michihito Niimura
The purpose of this study was to evaluate serum levels of basal insulin and glucose‐stimulated insulin, and to evaluate their correlations with androgen levels in women with acne. Serum levels of total testosterone (T), free testosterone (FT), dihydrotestosterone (DHT), dehydroepiandrosterone sulfate (DHEA‐S), sex hormone binding globulin (SHBG), insulin‐like growth factor‐1 (IGF‐1), and immunoreactive insulin (IRI) were measured and compared in thirty women with moderate or severe acne and thirteen healthy controls. Serum FT, DHT and DHEA‐S levels in the acne group were significantly higher than those in the control group. In the acne group, there were no significant correlations between insulin or IGF‐1 levels and T, FT, DHT and SHBG, despite the positive correlation between insulin and IGF‐1. In order to determine the effects of insulin secretion as a dynamic response to an oral glucose tolerance test (OGTT) on serum androgen levels in acne patients, we examined the responses of serum insulin and androgen levels to a 75 g, 2 hour OGTT in the acne group and in the control group. Basal insulin levels were not significantly higher than those in the control group, but the summed insulin levels during the OGTT in the acne group were significantly higher than those in the control group. Serum T and FT levels in the acne group decreased during the OGTT, but these changes were not so significant when compared to normal controls. In conclusion, we tried to demonstrate mild insulin resistance during the OGTT in acne patients. However, postmeal transient hyperinsulinemia does not seem to play an important role in determining hyperandrogenemia in acne patients.
Journal of Dermatology | 1992
Hiroshi Aizawa; Michihito Niimura
Spironolactone at 50 mg/day was orally administered for four weeks to 13 male patients with rosacea in order to observe its clinical effectiveness. Serum estradiol (E2), 17OH‐progesterone (17OH‐P4), testosterone (T), androstenedione (Δ4A), dihydrotestosterone (DHT), dehydroepiandrosterone sulfate (DHEA‐S) were measured prior to and after treatment. Although there were no significant changes in T, Δ4A, DHT, or DHEA‐S, the serum levels of 17OH‐P4 increased significantly. E2 tended to increase, although the change was not significant Two of the 13 patients discontinued spironolactone treatment because of general malaise, but seven of the remaining eleven patients exhibited an improvement in their rosacea. These findings demonstrate that a low dose of spironolactone is effective in the treatment of rosacea in some male patients and suggest that it is possible that changes in the metabolism of sex steroid hormones such as cytochrome p‐450 isozymes have some bearing on the etiology of rosacea.
Journal of Dermatology | 1996
Toshiya Ebata; Ronko Itamura; Hiroshi Aizawa; Michihito Niimura
Serum levels of sex hormones were measured in adult patients with atopic dermatitis (AD) and compared with those in sex‐ and age‐matched healthy controls. In 40 male patients with AD, serum levels of testosterone (T) (447 ± 96 vs 593 ± 149 ng/dl, P<0.001), free testosterone (FT) (14.6 ± 3.2 vs 20.0 ± 5.1 pg/ml, P<0.001) and estradiol (E2) (27.2 ± 7.2 vs 33.2 ± 7.9 pg/ml, P<0.05) were significantly lower and serum levels of luteinizing hormone (LH) (4.57 ± 1.6 vs 3.11 ± 1.2 mIU/ml, P<0.001) were significantly higher than those in healthy controls. There were no significant differences in serum levels of dihydrotestosterone (DHT), dehydroepiandrosterone sulfate (DHEA‐S), dehydroepiandrosterone (DHEA), or follicle stimulating hormone (FSH) between the two groups. In 25 female patients with atopic dermatitis, T, FT, DHT and DHEA‐S levels did not differ from controls. In conclusion, serum T levels were lower in male patients with AD. However, similar changes were not seen in female patients.
Journal of Dermatology | 1995
Hiroshi Aizawa; Yoshiko Nakada; Michihito Niimura
Androgens are essential for the development of acne. The object of this study was to elucidate the androgen status of women with adolescent (Tanners stage IV–V) acne alone and compare them to age‐matched normal controls. We measured serum levels of total testosterone (T), free testosterone (FT), dihydrotestosterone (DHT), and dehydroepiandrosterone sulfate (DHEA‐S) in 15 women with adolescent acne and 13 age‐matched healthy controls. No significant differences were found between the mean levels of T, FT or DHT levels in patients and controls. However, the mean levels of DHEA‐S in the patient population (1886 ± 829 ng/ml) were significantly (p<0.05) higher than normal controls (1287 ± 620 ng/ml). There was also no correlation between androgen levels and acne severity. Thus it is unlikely that serum androgens play a principal role in women with adolescent acne.
Journal of Dermatology | 1992
Hiroshi Aizawa; Michihito Niimura; Yukiko Kon
As part of a study of the mechanism of metronidazols efficacy in the treatment of acne and rosacea, its effects on the endocrine milieu and sebum excretion rate were assessed. Thirteen healthy males received oral metronidazole treatment (500 mg/day) for 4 weeks.
Journal of Dermatology | 1989
Ryoichi Kamide; Takeshi Ishikawa; Hiroshi Aizawa; Ikuko Aoki; Michihito Niimura
An 80‐year‐old Japanese woman with temporal arteritis was treated with systemic recombinant human interleukin‐2 (IL‐2) (1 × 106 unit/day for six weeks). The presenting symptoms of headache and skin necrosis and abnormal laboratory findings, such as an elevated erythrocyte sedimentation rate and CRP, promptly improved without any serious side effects. Although the pathogenesis of temporal arteritis and the mechanism(s) of the beneficial effect of IL‐2 on it still remain unknown, this preliminary study highly encourages further investigations.
Journal of Dermatology | 1992
Hiroshi Aizawa; Michihito Niimura
In order to evaluate the hormonal milieu in young men with severe acne, we measured serum estradiol (E2), total testosterone (T), free testosterone (FT), dihydrotestosterone (DHT), dehydro‐epiandrosterone sulfate (DHEA‐S), and sex hormone binding globulin (SHBG) levels in sixteen male patients aged 20–30 years with severe acne, including twelve cases of nodular‐cystic acne, and in seventeen age‐matched normal controls.
Journal of Dermatology | 1996
Toshiya Ebata; Hiroshi Aizawa; Ryoichi Kamide
Skin research | 1997
Hirono Izumi; Toshiya Ebata; Yuko Sato; Hiroshi Aizawa; Ryoichi Kamide; Michihito Niimura