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61.
Taurine improves insulin sensitivity in the Otsuka Long-Evans Tokushima Fatty rat, a model of spontaneous type 2 diabetes 总被引:9,自引:0,他引:9
Nakaya Y Minami A Harada N Sakamoto S Niwa Y Ohnaka M 《The American journal of clinical nutrition》2000,71(1):54-58
BACKGROUND: Taurine, a potent antioxidant, has been reported to improve streptozotocin-induced diabetes mellitus, in which the development of diabetes results from an attack by oxygen free radicals on pancreatic beta cells. However, taurine also increases the excretion of cholesterol via conversion to bile acid and would be expected to improve insulin resistance. OBJECTIVE: The effects of taurine on insulin sensitivity were examined in a model rat of insulin resistance and type 2 diabetes-the Otsuka Long-Evans Tokushima Fatty (OLETF) rat. DESIGN: Male OLETF rats were divided into 2 groups at the age of 16 wk: a taurine-supplemented group and an unsupplemented group. As a nondiabetic control, Long-Evans-Tokushima-Otsuka rats were used. An oral-glucose-tolerance test and hyperinsulinemic euglycemic clamp were performed at the ages of 23 and 25 wk. RESULTS: The OLETF rats had hyperglycemia and insulin resistance and they had a greater accumulation of abdominal fat than did control rats. Abdominal fat accumulation, hyperglycemia, and insulin resistance were significantly lower in the taurine-supplemented group than in the unsupplemented group. Serum and liver concentrations of triacylglycerol and cholesterol were significantly higher in the OLETF rats than in the control rats and were significantly lower in the taurine-supplemented group than in the unsupplemented group, presumably because of the increased secretion of cholesterol into bile acid. Taurine-supplemented rats also showed higher nitric oxide secretion, evidenced by increased urinary excretion of nitrite. CONCLUSION: Taurine effectively improves metabolism in OLETF rats by decreasing serum cholesterol and triacylglycerol, presumably via increased secretion of cholesterol into bile acid and decreased production of cholesterol because of increased nitric oxide production. 相似文献
62.
Are children living near high-voltage power lines at increased risk of acute lymphoblastic leukemia? 总被引:2,自引:0,他引:2
Kleinerman RA Kaune WT Hatch EE Wacholder S Linet MS Robison LL Niwa S Tarone RE 《American journal of epidemiology》2000,151(5):512-515
In the National Cancer Institute/Children's Cancer Group case-control study of childhood acute lymphoblastic leukemia (1989-1993), living in a home with a high-voltage wire code was not associated with disease risk. To further investigate risk near power lines, the authors analyzed distance to transmission and three-phase primary distribution lines within 40 m of homes and created an exposure index of distance and strength of multiple power lines (408 case-control pairs). Neither distance nor exposure index was related to risk of childhood acute lymphoblastic leukemia, although both were associated with in-home magnetic field measurements. Residence near high-voltage lines did not increase risk. 相似文献
63.
64.
Fuller TR Oka M Otsuka K Yokoyama N Liberman RP Niwa SI 《Psychiatric services (Washington, D.C.)》2000,51(7):864-866
INTRODUCTION BY THE COLUMN EDITORS: Because the mental health system in Japan has emphasized hospital-based treatment (1), patients with schizophrenia often remain institutionalized for long periods, even after their symptoms have stabilized. In addition, the introduction of modern community-based methods of treatment and rehabilitation was delayed by an antipsychiatry movement in the 1970s and the ascendance of a reductionistic biological approach to services (2). Lack of adequate outpatient services and community residential care in Japan has been a serious obstacle to destigmatization of mental disorders and has contributed to the heavy burden and stress experienced by families of mentally ill persons (3). More than 80 percent of patients discharged from mental hospitals return to live with their families, who are ill prepared to provide the supportive services required for community tenure.Involvement in work activities can facilitate community reentry for people with serious and persistent mental illness because employment displaces symptoms, provides structure and meaning in daily life, offers socialization with peers, and permits workers to earn income for shelter and food. In this issue's Rehab Rounds column, the authors describe an innovative vocational rehabilitation program for patients with schizophrenia that was designed to overcome obstacles to discharge and community adjustment. The program at Yabuki Prefecture Psychiatric Hospital, in the northern prefecture of Fukushima, Japan, has been successful in training patients for competitive work while capitalizing on the importance of work in Japanese culture and its traditionally supportive employer-employee relationships. The program is termed "hybrid" because it combines elements of transitional employment with supported employment (4). 相似文献
65.
Deli MA Sakaguchi S Nakaoke R Abrahám CS Takahata H Kopacek J Shigematsu K Katamine S Niwa M 《Neuroreport》2000,11(17):3931-3936
A hydrophobic, fibrillogenic peptide fragment of human prion protein (PrP106-126) had in vitro toxicity to neurons expressing cellular prion protein (PrP(C)). In this study, we proved that primary cultures of mouse cerebral endothelial cells (MCEC) express PrP(C). Incubation of MCEC with PrP106-126 (25-200 microM) caused a dose-dependent toxicity assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, lactate dehydrogenase release, bis-benzimide staining for nuclear morphology, and trypan blue exclusion test. Pentosan polysulphate (50-100 microg/ml), a drug effective in scrapie prophylaxis, dose-dependently attenuated the injury. MCEC cultures from mice homogenous for the disrupted PrP gene were resistant to the toxicity of PrP106-126. In conclusion, cerebral endothelium expressing PrP(C) may be directly damaged during spongiform encephalopathies. 相似文献
66.
H. Aotsuka K. Tobita H. Hamada M. Uchishiba S. Tateno K. Matsuo T. Fujiwara K. Niwa 《Pediatric cardiology》1996,17(6):351-359
The proximal isovelocity surface area (PISA) method for calculating volume flow through the regurgitant orifice has attracted
significant attention. A number of in vitro studies and clinical studies in adults suggest that the method is accurate. However,
when applying the method to children it must be noted that the absolute regurgitation volume is small, and the range of body
sizes is wide. This study investigated the accuracy of the PISA method for quantitative assessment of the severity of mitral
regurgitation in children. Twenty children aged 7 months to 12 years (average 4.7 years) with mitral regurgitation but without
interventricular shunt or aortic stenosis were selected for this study. Underlying cardiac diseases included atrioventricular
septal defects in nine, isolated mitral regurgitation in five, and association with other heart defects in six. The PISA radius
(r) and the duration of regurgitation (T) were measured on color M-mode recordings, with the M line passing through the center of the PISA. Assuming that the PISA
is a hemisphere, maximal regurgitant flow rate (MFR: ml/s) was calculated as MFR = 2π×~ r
2×~ V (r= maximal radius, V= aliasing velocity), and regurgitant stroke volume (RSVpisa) as RSVpisa = 2π×~ MSR ×~ V×~ T (MSR = mean square of the PISA radius during regurgitation). As a validating standard, total stroke volume (TSV) using two-dimensional
echocardiography determined by the area–length volumetry method and forward stroke volume (FSV) by the pulsed Doppler method
were measured, and regurgitant stroke volume (RSVD: RSVD= TSV − FSV) and regurgitant fraction (RF: RF = RSVD/TSV) were calculated. A linear correlation was found between MFR, RSVpisa, and RSVD (X) (MFR = 4.2X + 54.0, r= 0.84. RSVpisa = 1.0X + 9.8, r= 0.90), and both RSVpisa and MFR divided by body surface area (BSA: m2) revealed a significant correlation with regurgitant fraction (X) by nonlinear regression analysis (RSVpisa/BSA = 26.2 ×~
X/(1 − X) + 16.8, r= 0.85. MFR/BSA = 121.8 ×~ X/(1 − X) + 92.2, r= 0.79). It is concluded that maximal regurgitant flow rate, regurgitant stroke volume, and regurgitant fraction can be accurately
predicted in children using the PISA method by Doppler echocardiography. 相似文献
67.
Y Kataoka Y Sakurai K Mine K Yamashita M Fujiwara M Niwa S Ueki 《Pharmacology, biochemistry, and behavior》1987,28(1):101-103
The present study was designed to clarify the functional role of neuropeptide Y (NPY) in the regulation of muricide induced by olfactory bulbectomy (OB) in relation to that of noradrenaline (NA) in the medial amygdala (AME). NA injected into AME inhibited muricide dose-dependently in OB rats. NPY at doses of 5 and 10 micrograms/microliter injected alone into AME failed to suppress muricide. When NPY 10 micrograms was injected into AME in combination with the maximal non-effective dose of NA, which was determined in each rat, muricide was suppressed in 80% of OB rats. The present study has provided the first evidence suggesting that NPY may be involved in the regulation of OB-induced muricide. 相似文献
68.
Daisuke Ueda Kosuke Niwa Hiroshi Nishikawa Yasuaki Tsuchida Keigo Yamashita 《Clinical Case Reports》2022,10(8)
A 71‐year‐old woman was admitted to the hospital due to cardiac tamponade. Computed tomography revealed that the diameter and wall thickness of the ascending aorta were 36 and 9 mm, respectively. An emergent ascending aortic replacement was performed uneventfully. The pathological findings indicated frank rupture of intramural hematoma. 相似文献
69.
70.
Niwa K Hirose R Mizuno T Hirose Y Tamaya T 《European journal of gynaecological oncology》2007,28(2):145-146
An extremely rare case of a pseudomyxoma peritonei (PMP) and mucinous pyometral fluid, possibly arising from an ovarian borderline mucinous tumor is reported. A 68-year-old Japanese patient received an expolatory laparatomy under a working diagnosis of a PMP, left ovarian cystic tumor and an umbilical hernia. Surgery and platinum-based chemotherapy induced a 15-month disease-free condition. 相似文献