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41.
Toshikazu Saito M.D. Hideaki Ishizawa M.D. Fumiaki Tsuchiya M.D. Hiroki Ozawa M.D. Naohiko Takahata M.D. 《Psychiatry and clinical neurosciences》1986,40(2):189-194
Abstract: Monoamine and their acid metabolites were determined in the CSF of 18 drug-treated chronic schizophrenic patients with the symptoms of tardive dyskinesia and neuroleptic-induced Parkinsonism (Parkinsonism). Six healthy volunteers were used as the control group.
The norepinephrine (NE) levels were found to be significantly higher in the patients with tardive dyskinesia than in the controls. Furthermore, elevated CSF NE levels were also observed in the patients with Parkinsonism. Epinephrine (E) and Dopamine (DA) were not present in the CSF of the control group, whereas measurable levels of DA could be detected in 4 out of 9 and E was found in 8 out of 9 patients with tardive dyskinesia. The mean concentration of HVA was slightly but not significantly elevated in the patients with tardive dyskinesia and Parkinsonism. The mean values of CSF 5-HIAA were all within the normal range in both patient groups. From the above results, it was suggested that abnormal adrenergic activity rather than abnormal dopaminergic activity may play an important role as a mechanism in the etiopathogenesis of extrapyramidal disorders. Furthermore, in the patients with Parkinsonism, CSF neurochemical observations were similar to those of the patients with tardive dyskinesia in this study. It may help to explain the clinical coexistence of tardive dyskinesia and neuroleptic-induced Parkinsonism. 相似文献
The norepinephrine (NE) levels were found to be significantly higher in the patients with tardive dyskinesia than in the controls. Furthermore, elevated CSF NE levels were also observed in the patients with Parkinsonism. Epinephrine (E) and Dopamine (DA) were not present in the CSF of the control group, whereas measurable levels of DA could be detected in 4 out of 9 and E was found in 8 out of 9 patients with tardive dyskinesia. The mean concentration of HVA was slightly but not significantly elevated in the patients with tardive dyskinesia and Parkinsonism. The mean values of CSF 5-HIAA were all within the normal range in both patient groups. From the above results, it was suggested that abnormal adrenergic activity rather than abnormal dopaminergic activity may play an important role as a mechanism in the etiopathogenesis of extrapyramidal disorders. Furthermore, in the patients with Parkinsonism, CSF neurochemical observations were similar to those of the patients with tardive dyskinesia in this study. It may help to explain the clinical coexistence of tardive dyskinesia and neuroleptic-induced Parkinsonism. 相似文献
42.
43.
Yoshihiro Hanaki Satoru Sugiyama Kazumi Taki Tadayuki Kato Shohachi Suzuki Takayuki Ozawa Prof. M.D. 《Heart and vessels》1988,4(3):149-152
Summary The present study was designed to clarify whether or not a difference between arterial and venous lactate (lactate) levels is useful for evaluation of mitochondrial function in ischemia-reperfused myocardium. In the first experiment, 12 dogs were divided into 2 groups: 10-min occlusion of the left anterior descending coronary artery (LAD) followed by 10-min reperfusion, or 30-min occlusion followed by 40-min reperfusion, were performed. The lactate levels in the femoral artery and the great cardiac vein were measured enzymatically. Lactate was reversed immediately after occlusion. Ten min and 20 min were required for the recovery of lactate in the 10-min-occlusion with 10-min-reperfusion, and 30-min-occlusion with 40-min-reperfusion groups, respectively. In the second experiment, 36 dogs were divided into 6 groups: 10-min occlusion of LAD; 10-min occlusion with 10-min reperfusion; 30-min occlusion; and 30-min occlusion with 10-, 20-, or 40-min reperfusion were performed. Mitochondria from normal and occluded or reperfused areas were prepared, and the respiratory function of the mitochondria was measured polarographically. No significant decreases in the mitochondrial function were observed in the 10-min-occlusion, and 10-min-occlusion with 10-min-reperfusion groups. On the other hand, respiratory function of mitochondria was impaired by 30-min occlusion and was not improved by 10- or 20-min reperfusion. Significant recovery in the mitochondrial function was observed after 40-min reperfusion. That is, differing recovery time courses between lactate and the mitochondrial function were observed. 相似文献
44.
Hikaru Matsuda Yoshiyuki Taenaka Nobukazu Ohkubo Masakatu Ohtani Kyouichi Nishigaki Shigeaki Ohtake Takuya Miura Nobuyuki Taenaka† Hisateru Takano Hajime Hirose Yasunaru Kawashima 《Artificial organs》1988,12(5):423-430
Pneumatic ventricular assist device (VAD) was utilized for cardiogenic shock after intracardiac operation in two children with complex cardiac anomalies based with single ventricle. In the first case (a 10-year-old), after a modified Fontan operation, VAD was placed between the functional left atrium and ascending aorta, serving as a "artificial single ventricle" with neither pumping chamber nor artificial support in the right side of the heart. The systemic circulation was maintained by keeping relatively high central venous pressure. In another child (a 3-year-old) who underwent repair of incompetent atrioventricular valve leaving intracardiac lesions, VAD was placed between the common atrium and ascending aorta, serving as a pump for both pulmonary and systemic circulation with regulation of pulmonary blood flow through an aortopulmonary Gore-Tex shunt. The circulatory assist with VAD was utilized for 5 and 6 days, respectively. Although weaning from the device was not feasible in both patients because of the pulmonary dysfunction, these experience showed the possible use of VAD for cardiogenic shock after surgery in patients with complex cardiac anomalies. 相似文献
45.
K Takeuchi K Matsubayashi S Kimura A Kawamoto T Ozawa K Shimada 《Nihon Ronen Igakkai zasshi. Japanese journal of geriatrics》1992,29(7-8):549-553
Lacunes on brain MRI, causal blood pressure, 24-hour ambulatory blood pressure and common carotid blood flow measured by the doppler method were studied in 31 elderly patients with Parkinson's disease (mean age 67.5 +/- 7.3 years). Nineteen patients with Parkinson's disease (61%) had at least one lacune. Patients with lacunes (P(+)) were significantly higher in age than patients without lacune (P(-)). The difference of casual blood pressure between patients in the two groups was not significant. On the other hand, the average of ambulatory blood pressure measurements during a 24-hour period was significantly higher in the P(+) group than in the P(-) group. The average of carotid blood flow was also significantly lower in the P(+) group than in the P(-) group, however, after adjustment for age, the difference between them became insignificant. In conclusion, the incidence of silent lacunes on brain MRI was fairly common in elderly patients with Parkinson's disease. A high average 24-hour ambulatory blood pressure was suggested to be one of the risk factors of lacunar stroke in elderly cases of Parkinson's disease. The concept of "combine type" in Parkinsonism was supposed to be suitable as well as in senile dementia of Alzheimer type. 相似文献
46.
K Matsubayashi S Kimura T Iwasaki K Okumiya T Hamada M Fujisawa K Takeuchi T Kawamoto T Ozawa 《Nihon Ronen Igakkai zasshi. Japanese journal of geriatrics》1992,29(11):823-828
Visual analogue scale of happiness (VAS-H) was applied to elderly Himalayan highlanders to investigate the influence of life-style and socio-cultural background on subjective happiness. The score of "VAS-H" and neuropsychological function tests in 733 Himalayan highlanders who belonged to 5 separate villages were compared with those in 313 Japanese elderly subjects. The places of study consisted of 4 villages (Khalimabad; K, Gulmit; G, Pasu; P, Shimshal; S) in Hunza area in Pakistan, and Namche Bazar; N in Nepal. Degree of modern civilization was highest in K, followed by N, G, P and lowest was that in S by historical and sociological aspects. The mean VAS-H sore in Himalayan highlanders and the degree of modern civilization in the area was in inverse proportion. Himalayan elderly women showed a significant lower score on VAS-H compared with elderly Himalayan men or elderly Japanese subjects. The VAS-H score in the Japanese elderly correlated significantly with the stability of posture and walk, and that of Himalayan highlanders correlated significantly with manual skill. In conclusion, the life style or socio-cultural background strongly affected subjective happiness in the elderly. The VAS-H was useful in comparing subjective happiness in different cultures. 相似文献
47.
Incidental brain lesions on magnetic resonance imaging and neurobehavioral functions in the apparently healthy elderly. 总被引:9,自引:0,他引:9
K Matsubayashi K Shimada A Kawamoto T Ozawa 《Stroke; a journal of cerebral circulation》1992,23(2):175-180
BACKGROUND AND PURPOSE: Controversies exist whether incidental neuroradiological brain lesions in the elderly are associated with depressed neuropsychological function. To address this important issue in a cross-sectional study, we related brain lesions on magnetic resonance imaging to a variety of cognitive and neurobehavioral function tests in an independent, normal elderly population. METHODS: We studied 73 independent asymptomatic elderly individuals (mean +/- SD age 70 +/- 6 years) to determine the relations between degree of brain atrophy, location and number of "lacunes," and grade of periventricular hyperintense lesions with a variety of cognitive and neurobehavioral function scores. RESULTS: We found that severity of neuroradiological changes increased while neuropsychological function scores declined with age. After adjustment for the effect of age, advanced periventricular hyperintensities, but not brain atrophy or patchy "lacunar" lesions, were associated with declines in all neuropsychological functions tested. CONCLUSION: We conclude that incidental advanced periventricular diffuse or patchy white matter changes may play a role in the development of cognitive and neurobehavioral impairments in apparently normal elderly persons. 相似文献
48.
Chromogenic anti-Xa activity procedures were developed for monitoring LMW heparins on the Automated Coagulation Laboratory 300 Plus (ACL, Instrumentation Laboratory) system. For daily monitoring, a "Routine" procedure was devised which allows accurate measurements between plasma levels of 0.1 and 1.0 u/ml LMW heparin. For lower levels a "Routine-Low" method was developed which assesses activities between 0.05 and 0.4 u/ml. Due to variabilities in dODs of individual baseline plasmas, levels below 0.05 u/ml might be inaccurate when pooled normal plasma is used to establish the reference curve. While levels less than 0.05 u/ml should rarely be encountered when monitoring LMW heparins for routine clinical use, pharmacokinetic studies require accurate measurements below that level. For this reason a "Research-High" and a "Research-Low" procedure was designed. For these procedures a study subject's own baseline plasma was used to establish the reference curve. The "Research-High" measures activities between 0.4 and 2.0 u/ml, the "Research-Low" between zero and 0.4 u/ml. The procedures have excellent within-run and inter-run coefficients of variation (less than 5%) and high levels of accuracies. Even inter-instrumental reproducibilities are less than 10%. Different manufacturers' LMW heparins can be analyzed by these assays. The procedures offer full automation, great cost-effectiveness due to lower reagent volumes, rapid turn-around time and great accuracy and reproducibility. 相似文献
49.
Okamoto E Watanabe K Hashiba K Inoue T Iwazawa E Momoi M Hashimoto T Mitamura Y 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(5):495-502
An implantable secondary battery is one of the key components in a total artificial heart system. Because a 2 year cycle life is required, the cycle life of the secondary battery as well as its charge and discharge properties are important parameters for selection of an appropriate battery. We carried out cycle life tests on four kinds of rechargeable batteries (a Ni-MH secondary battery, a Ni-Cd secondary battery, a Li-ion battery with a graphite anode, and a Li-ion battery with a nongraphitizable carbon electrode) to determine their suitability as implanted back-up batteries. Each of the batteries was charge/discharge cycled at 37 degrees C to 39 degrees C using a charge current of 1 C ampere, and they were each fully discharged under either pulsatile discharge loads, which mimicked pulsatile operation, or a nonpulsatile load equivalent to the average of the pulsatile loads. The two Li-ion batteries made by different manufacturers both met the minimum requirement of cycle life of more than 1,500 cycles, considering safety coefficient regardless of the discharge pattern. In addition, the temperature increase of these Li-ion batteries (3 degrees C) was lower than that of Ni-Cd and Ni-MH batteries (15-25 degrees C). Out of these four batteries, the two Li-ion batteries are the most suitable for use in a totally implantable artificial heart system. 相似文献
50.
Ishikawa-Sakurai M Yoshida M Imamura M Davies KE Ozawa E 《Human molecular genetics》2004,13(7):693-702
An intracellular protein, dystrophin, plays an important role in keeping muscle fibers intact by binding at its N-terminal end to the subsarcolemmal cytoskeletal actin network and via its C-terminal end to the transmembraneous protein beta-dystroglycan. Duchenne muscular dystrophy is caused by the loss of dystrophin, which can result from the loss of this binding. The N-terminal part of the latter binding site of dystrophin has been well documented using overlay assay and X-ray diffraction assays. However, the binding site at the C-terminal region of dystrophin has not been examined in detail. In the present work, we report a detailed analysis of the C-terminal binding domain as follows. (1). The full binding activity corresponding to the effective binding in vivo is expressed by the dystrophin fragment spanning amino acids 3026-3345 containing the ZZ domain at the C-terminus. Determination of this binding range is important not only for understanding of the mechanism of dystrophy, but also useful for the design of truncated dystrophin constructs for gene therapy. (2). The ZZ domain binds to EF1 domain in the dystrophin fragment to reinforce the binding activity. (3). The cysteine 3340 in the ZZ domain is essential for the binding of dystrophin to beta-dystroglycan. A reported case of DMD due to missense mutation C3340Y may be caused by inability to fix dystrophin beneath the cell membrane. (4). The binding mode of utrophin is different from that of dystrophin. The difference is conspicuous concerning the cysteine residues present in the ZZ domain. 相似文献