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Publications (5)5.77 Total impact

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    ABSTRACT: We studied the time course of serum insulin level in a patient who injected large amounts of regular insulin in an attempted suicide. A 58-year-old woman attempted suicide by subcutaneously injecting herself with 2400 U regular insulin. On arrival, the serum glucose level was 2.4 mmol/L (44 mg/dL) and the serum insulin level was 40,000 pmol/L (5700 μIU/mL). The serum insulin level was high, with a maximum of 110,000 pmol/L (16,000 μIU/mL) at 13 h after injection, followed by an initial rapid decrease and a subsequent slow decrease, with hyperinsulinemia lasting as long as 5 days after injection. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2012.00211.x, 2012).
    Journal of diabetes investigation. 10/2012; 3(5):468-70.
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    ABSTRACT: In contrast to the large number of studies on autoimmunity against the thyroid gland in patients with type 1 diabetes mellitus, little is known about the anti-islet autoimmune status in patients with autoimmune thyroid diseases (AITDs). We therefore studied the anti-islet autoimmune status in patients with AITD and the clinical and genetic characteristics of AITD patients with anti-islet autoimmunity. The positivity and titer of glutamic acid decarboxylase antibody (GAD Ab) were studied in 866 Japanese patients with AITD (546 with Graves disease and 320 with Hashimoto thyroiditis), 221 patients with thyroid disease of nonautoimmune origin, and 282 control subjects. The clinical characteristics and genotypes of HLA-DRB1, DQB1, and CTLA4 were compared between AITD patients with and without GAD Ab. The prevalence of GAD Ab was significantly higher in AITD patients than in control subjects (5.8% vs 2.1%, P = .01), particularly in Graves disease (7.1% vs 2.1%, P = .0019). The prevalence of diabetes mellitus was significantly higher in AITD patients with GAD Ab than in those without (40.0% vs 10.1%, P < .0001), particularly in those with a high titer of GAD Ab (high vs low titer: 64% vs 16%, P = .001) and also in those positive for insulinoma-associated antigen 2 (IA-2) Ab (IA-2 positive vs negative: 75.0% vs 31.3%, P = .016). The AITD patients with GAD Ab were characterized by younger age at onset of diabetes, lower body mass index, higher hemoglobin A(1c) level, and higher frequency of insulin therapy than those without GAD Ab. The frequency of the DRB1*0405-DQB1*0401 haplotype was significantly higher in AITD patients with GAD Ab than in those without GAD Ab and control subjects. A single nucleotide polymorphism (rs3087243) of CTLA4 was significantly associated with AITD, but not with positivity of GAD Ab. These results indicate that patients with AITD, and in particular Graves disease, are prone to develop β-cell autoimmunity and insulin-requiring diabetes, particularly those with a high titer of GAD Ab and/or positive for both GAD and IA-2 Ab. Glutamic acid decarboxylase Ab positivity in AITD patients was associated with HLA, conferring susceptibility to type 1 diabetes mellitus.
    Metabolism: clinical and experimental 06/2011; 60(6):761-6. · 3.10 Impact Factor
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    ABSTRACT: The maximum dosage of metformin allowed for clinical use in Japan is much less than half that in Western countries, making it difficult to apply the results of clinical trials in Western countries to Japanese patients. In particular, the efficacy and safety of metformin in elderly patients are largely unknown. Among 1508 patients who were newly prescribed metformin at our hospital from 2000-2006, patients with sufficient clinical data were retrospectively studied for the safety (n=1132) and efficacy (n=568) of the drug. Of 568 patients in whom the efficacy of metformin was analyzed, 180 patients (31.7%) were elderly, aged 65 years or over. Metformin was effective for the treatment of type 2 diabetes in Japanese patients, with significant improvement in HbA1c level at all time-points after 1 month, with the largest decrease by approximately 0.9% in patients treated with 750 mg/day and approximately 0.7% in those treated with 500 mg/day, at 4 months. Metformin improved glycemic control in elderly patients as well as non-elderly patients. The efficacy was independent of age, sex, degree of obesity and concomitant use of other drugs. No significant difference was observed in elevated lactic acid levels between elderly and non-elderly patients. No case of lactic acidosis was observed. These results suggest that the efficacy of metformin in Japanese elderly patients with type 2 diabetes is not different from that in non-elderly patients, and that its safety might be linked to specific and well-documented contraindications rather than age itself.
    Geriatrics & Gerontology International 01/2011; 11(1):55-62.
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    ABSTRACT: The antiproteinuric effect of the angiotensin II receptor-antagonist losartan has been observed in patients with type 2 diabetes mellitus (T2DM). Proteinuria is considered to be a predictor of the progression of kidney disease. The aims of the present study were to compare and examine the ability of losartan and amlodipine to ameliorate albuminuria in hypertensive Japanese patients (systolic blood pressure ≥140 mm Hg or diastolic blood pressure ≥90 mm Hg) with T2DM and whether the change in albuminuria was associated with a change in glomerular filtration rate (GFR). This prospective, open-label, randomized, comparative study was conducted over 3 months at the Kinki University School of Medicine, Osaka-Sayama, Japan. Hypertensive patients with T2DM were enrolled and randomly assigned to 1 of 2 study groups receiving either losartan (25-100 mg/d) or the calcium channel-blocker amlodipine (2.5-5 mg/d). Urinary albumin excretion (UAE), creatinine clearance, and GFR were recorded at study initiation (baseline) and study end (month 3). The GFR was measured from the fractional renal accumulation of (99m)Tc-diethylenetriaminepentaacetic acid. Adverse events (AEs) were monitored by a clinical research nurse during the examination. Fifty patients were asked to enroll and 38 returned the informed written consent. Thirty-five Japanese patients were included in the final study analysis. Seventeen patients were assigned to the losartan group (male sex, 10 [58.8%]; mean [SD] age, 58.1 [8.2] years) and 18 were assigned to the amlodipine group (male sex, 10 [55.6%]; mean [SD] age, 57.4 [8.9] years); no significant between-group difference in demographics was observed. A significant decrease from baseline to month 3 of mean (SD) UAE was observed in the losartan group (352.5 [556.6] mg/d vs 275.7 [466.1] mg/d; P = 0.048). No significant difference in mean (SD) UAE was observed in the amlodipine group for the same time period (298.2 [416.6] mg/d vs 322.7 [415.4] mg/d). There was a statistically significant difference found in the mean (SD) percent change of UAE from baseline to month 3 in the losartan group compared with the amlodipine group (-23.52 [28.42] vs +27.90 [63.51]; P = 0.004). Neither group was associated with a significant change in GFR during the course of the study. No patient discontinued the study due to AEs that were considered, by the investigator, to be possibly or probably associated with study treatment. Treatment with losartan, but not amlodipine, was associated with a reduction in albuminuria in these hypertensive Japanese patients with T2DM within a period as short as 3 months. Neither drug was associated with a significant change in GFR. Therefore, the reduction of UAE was independent of a change in the GFR.
    Current Therapeutic Research 03/2007; 68(2):94-106. · 0.45 Impact Factor
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    ABSTRACT: We report a rare case of type 1 diabetes in a woman associated with acromegaly who was treated with surgery after pregnancy. An 18-year-old woman came to our hospital in April, 1998, complaining of thirst, polydipsia, polyuria, appetite loss, body weight loss of 8 kg in a month, and amenorrhea beginning 2 months earlier. Based on laboratory data, she was diagnosed as having type 1 diabetes mellitus. Although we suspected her of having acromegaly because of high growth hormone (GH) levels (6.9 or 8.5 ng/ml), blood levels of insulin-like growth factor 1 (IGF-1) and IGF-binding protein-3 (IGFBP-3) were within normal range and the circadian rhythm of her blood GH levels was normally maintained. Her blood GH level was elevated to 12.6 ng/ml 15 minutes after a TRH administration. Blood GH levels were suppressed from 49 ng/ml to 1.5 ng/ml 4 hours after an oral administration of 2.5 mg of bromocriptine. A magnetic resonance images (MRIs) showed pituitary swelling, but no nodules were found in the pituitary. Therefore, we diagnosed her as having acromegaly and observed her without surgery, while prescribing diet therapy and intensive insulin therapy for diabetes. We started a treatment of oral administration of 7.5 mg of bromocriptine per day for the acromegaly from April 28, 2000, because her elevated GH was suspected of causing her diabetes to be poorly controlled. During a pregnancy from October, 2000 to September, 2001, diabetic control was improved with increased administration of insulin under a constant dose of bromocriptine. She delivered a normal full-term infant. After the bromocriptine therapy was stopped as she hoped to breastfeed, blood levels of GH and IGF-1 became elevated and her diabetic control deteriorated. As her pituitary tumor observed in pituitary MRIs became larger during the course, a transsphenoidal surgery was performed on March 8, 2002. After the surgery, blood levels of GH and IGF-1 lowered and diabetic control improved again. We concluded as follows: to rule out acromegaly in patients with poorly controlled diabetes, 1) measurements of serum GH and IGF-1 should be performed, and 2) pituitary MRIs should be performed if blood levels of GH or IGF-1 are high.
    Endocrine Journal 09/2005; 52(4):413-20. · 2.23 Impact Factor