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N-(2-Ethylhexyl)-3-hydroxybutyramide hydrogen succinate (M-2H) has been reported to increase REM sleep. The effects of M-2H on the metabolisms of monoamines which have been implicated in the regulation of the sleep-wakefulness cycle were studied in rats. M-2H (500 mg/kg p.o.) increased the levels of 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid and 3-methoxy-4-hydroxyphenylethyleneglycol sulfate in various regions of the rat brain. However, no appreciable changes occurred in levels of serotonin (5-HT), norepinephrine, dopamine, or 3,4-dihydroxyphenylacetic acid. The effect of M-2H (500 mg/kg p.o.) on 5-HT metabolism was investigated with intraventricularly-injected [14C]-5-HT. Although [14C]-5-HT level was not significantly changed, [14C]-5-HIAA level was above control level in four brain regions such as the hypothalamus, hippocampus, midbrain and pons-medulla at 3 h after the administration of M-2H. M-2H retarded the efflux of intraventricularly-injected [14C]-5-HIAA in all brain regions except the cortex. These results suggest that M-2H preferentially impaired the transport system for acid metabolites of monoamines, resulting in increase of monoamine metabolite levels in the brain. 相似文献
4.
Kenji Yoshimi Masatoshi Takeda Tsuyoshi Nishimura Takashi Kudo Yu Nakamura Kunitoshi Tada Nobuyoshi Iwata 《Brain research》1991,560(1-2):149-158
Changes in MAP2 and clathrin immunoreactivity were studied in gerbil hippocampus after transient cerebral ischemia. MAP2 immuno-reactivity decreased significantly by 1 h in the subiculum-CA1 and CA2 areas which correspond to reactive change, while no decrease was observed in CA1 until day 4. Before the initiation of delayed neuronal death, MAP2 immunoreactivity was not changed in CA1. On the other hand clathrin immunoreactivity increased in the pyramidal cell layer of CA1 by 3 h after ischemia and remained high for 2 days. Clathrin immunoreactivity in the pyramidal cell layer of CA1 diminished after delayed neuronal death. The transient change of clathrin was noted especially in CA1 in the period prior to delayed neuronal death. These results imply an abnormal change in clathrin turnover after ischemia, which may participate in the pathogenesis of delayed neuronal death. 相似文献
5.
Symptomatic narcolepsy, once regarded as common, is now believed to be very rare. A 32-year-old man had a history of recurrent sleep attacks. A magnetic resonance imaging scan revealed a third ventricle tumor. The tumor was totally removed, and the histology was a craniopharyngioma. The symptoms ceased after the operation. The chronological correlation and the anatomical location of the tumor suggest that the patient had a symptomatic narcolepsy caused by the tumor. This is the first report that documents the cessation of narcolepsy attacks after tumor removal. 相似文献
6.
We report a 47-year-old alcoholic man with alcoholic pellagra encephalopathy (APE) showing myoclonus and ataxia as chief complaints. He had been a heavy drinker for 30 years. He had noticed appetite loss and subsequently showed a subacutely progressive gait disturbance. He had no history of diarrhea, dementia, or dermatitis. On admission, he showed severe alcoholic liver cirrhosis with a large amount of ascites, limbs and truncal ataxia, myoclonus of the limbs and areflexia, although his consciousness was alert and there were no sign of dermatitis. Though the plasma level of ammonia was normal, we started administration of amino acids suspecting hepatic encephalopathy. Symptoms showed no improvement, and subsequent administration of thiamine was also ineffective. A decreased serum level of niacin was demonstrated. After administration of nicotinamide, the symptoms improved gradually. This patient received a diagnosis of APE. Endemic pellagra, characterized by the classical triad of dermatitis, diarrhea and dementia, is known to be caused by a dietary deficiency of the niacin, and has now become very rare in developed countries. At present, pellagra is encountered most often in patients with chronic alcoholism, which is called APE. APE patients often show only disturbance of consciousness. Although several reports has described ataxia and myoclonus in patients with APE, APE patients with myoclonus and ataxia as chief complaints have not previously been reported. On autopsy cases, central chromatolysis of neurons in the dentate nucleus of the cerebellum, gracile and cuneate nuclei, and the Clarke's column has been demonstrated. The APE patients would show myoclonus and ataxia as their first symptoms. In conclusion, we would like to emphasize that administration of niacin should be started for the treatment of chronic alcoholic patients showing myoclonus and ataxia even without the classical triads found in endemic pellagra patients. 相似文献
7.
Akihiko Suto Akira Tsuyuki Nobuyoshi Hiraoka Yasuhiro Hosoda Kiyoshi Kikuchi Yasuo Fujishir 《Surgery today》1994,24(10):915-917
A case of cystadenocarcinoma of the appendix with a large cystic lesion is reported. A 49-year-old man undergoing a routine ultrasonic scan was incidentally found to have an abdominal mass measuring some 30 cm in size. The clinical presentation was asymptomatic, and the patient underwent a laparotomy without ascertaining a diagnosis preoperatively. The lesion, which derived from the appendix, was removed and was found to be cystic and contained huge amounts of mucin. The histological findings revealed a well-differentiated cystadenocarcinoma of the appendix, and immunohistochemical staining of the epithelium and mucinous implants in the mass demonstrated a positive reaction for carcinogenic antigens, including carcinoembryonic antigen and carbohydrate antigen. 相似文献
8.
A model was developed which estimates the costs of osteoporosis risk evaluation and treatment, and the resulting savings in terms of reduced fracture frequency, for the adult female population of the United States. In the absence of treatment, the model predicts 1.44 million fractures will occur annually from non-violent causes. Treatment of all women beginning at age 50 with an agent that slows bone loss by 50% would reduce the number of these fractures by 0.59 million. Selective treatment of the 47% of women at the greatest fracture risk would reduce the number of fractures by 0.45 million, but would only cost 47% as much as treating all women. Additional data are required before the model can be used to evaluate specific treatment regimens. However, it appears that selective treatment of those at highest risk would yield the greatest benefit to cost ratio, if only benefits related to reduced fracture frequency are considered. 相似文献
9.
Relevance of inflammatory cell infiltrates for complete atrioventricular block in experimental murine myocarditis. 总被引:2,自引:0,他引:2
BACKGROUND: There are few systemic pathologic studies on myocarditis. This study aimed to clarify the pathologic characteristics of murine myocarditis. METHODS: We recorded serial electrocardiograms in experimental viral myocarditis in mice and then examined their cardiac pathology. After taking baseline electrocardiograms, we inoculated the mice intraperitoneally with the encephalomyocarditis virus. Electrocardiograms were serially recorded until 220 days after the virus inoculation. RESULTS: Serial electrocardiograms revealed ectopic beats, low voltage of the QRS complex, and the appearance of complete atrioventricular (AV) block. Corresponding myocardial lesions were found in the hearts of mice with these ectopic beats. Mononuclear cell infiltrations into the His bundle were most frequently found in mice with complete AV block. CONCLUSIONS: Inflammatory change with cellular infiltrations was the most common pathologic finding in mice with complete AV block. In clinical settings, anti-inflammatory therapy might be recommended for patients with myocarditis complicated with conduction disturbances. 相似文献
10.
Nobuyoshi Kawaharada Kiyofumi Morishita Johji Fukada Yoshikazu Hachiro Yasuaki Fujisawa Tatsuya Saito Yoshihiko Kurimoto Tomio Abe 《European journal of cardio-thoracic surgery》2005,27(4):622-625
OBJECTIVE: The risk of stroke caused by dislodgment of loose atheromatous plaque or mural emboli is increased by cross-clamping of the aorta. Some patients undergo descending thoracic aortic aneurysm repair with proximal aortic cross-clamping between the left common carotid artery and the left subclavian artery. The objective of this study was to determine the influence of proximal aortic cross-clamping in arteriosclerotic aneurysm or dissecting aneurysm repair. METHODS: Between May 1984 and May 2003, 81 patients underwent elective surgery for distal arch or descending aortic aneurysm repair with proximal aortic cross-clamping between the left common carotid artery and the left subclavian artery. To evaluate the influence of the proximal aortic cross-clamping, patients were divided into two groups: patients who had undergone arteriosclerotic aneurysm repair (group I, n=25) and patients who had undergone dissecting aneurysm repair (group II, n=56). RESULTS: Eight (9.9%) of the 81 patients had a stroke. Six strokes occurred in operations for arteriosclerotic aneurysm repair group I and two strokes occurred in operations for dissecting aneurysm repair group II (24 vs 3.6%; p=0.009). In-hospital mortality rates were 12% in group I and 8.9% in group II (p=0.70). Major postoperative complications included renal failure requiring hemodialysis (in 4.2% of the patients in group I and in 8.3% of the patients in group II, p=0.99) and pulmonary complication (in 20% of the patients in group I and in 16% of the patients in group II, p=0.67). CONCLUSION: Cross-clamping between head vessels should be avoided if at all possible when operating on patients who have arteriosclerotic descending thoracic aneurysms. 相似文献