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The effects of consecutive oral administration of morphine on the cyclic AMP synthesizing system and cyclic AMP dependent protein kinase activity in the cerebral cortex of mice were examined. The administration of morphine (2--4 weeks) induced an increase of the cyclic AMP formation by activating adenylate cyclase, whereas responses of the cyclic AMP synthesizing system to biogenic amines (norepinephrine, dopamine and histamine) added in vitro was found to be significantly attenuated in these animals. Cyclic AMP dependent protein kinase activity in the cerebral cortex was also increased following a consecutive oral administration of morphine. These changes in the activities of adenylate cyclase and protein kinase were found mainly in crude mitochondrial and/or synaptosomal fractions. Morphine induced decrease in the response of the cyclic AMP synthesizing system to biogenic amines was rapidly reversed, and a significant increase of the cyclic AMP formation in the presence of added norepinephrine compared with that found in morphinized animals was observed following the administration of levallorphan, a narcotic antagonist. On the other hand, the changes in adenylate cyclase and cyclic AMP dependent protein kinase activities were not affected significantly by levallorphan administration. These results suggest that alterations in activities of cyclic AMP synthesizing system and of cyclic AMP dependent protein kinase may be involved in processes of the formation of morphine dependence. Possible involvement of abrupt increments in the sensitivity of "norepinephrine receptor-adenylate cyclase" system and a subsequent increase in cerebral cyclic AMP is also suggested as a cause of morphine withdrawal syndrome. 相似文献
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I Arai C Usuki-Ito M Muramatsu S Otomo T Shiraishi Y Oomura 《Physiology & behavior》1990,47(1):197-202
The involvement of a feeding-related endogenous sugar acid, 2-buten-4-olide (2-B4O) on central regulation of gastric acid secretion, and its antiulcer effects on several gastric and duodenal experimental ulcer models were investigated in rats. Spontaneous gastric acid secretion was not affected by 2-B4O at doses below 10 mg/kg. The peripheral secretagogue-stimulated gastric secretions were significantly increased by pretreatment with 2-B4O. Gastric acid secretion induced by 2-deoxy-D-glucose (2-DG) was significantly suppressed by pretreatment with 2-B4O at doses between 0.1 and 100 mg/kg. Gastric and duodenal ulcerations induced by cold stress plus indomethacin, restraint and water immersion stress, pylorus ligation or cysteamine were also inhibited by pretreatment with 2-B4O. The results suggest that antiulcer effects of 2-B4O are due to suppression of gastric acid secretion via reduction of activity of the vagus nerve and gastric-related hypothalamic neurons. Thus, 2-B4O may be useful for treatment of gastroduodenal ulcer. 相似文献
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Yoshikazu Uchiyama Akiko Abe Chisako Muramatsu Takeshi Hara Junji Shiraishi Hiroshi Fujita 《Journal of digital imaging》2015,28(1):116-122
Detection of lacunar infarcts is important because their presence indicates an increased risk of severe cerebral infarction. However, accurate identification is often hindered by the difficulty in distinguishing between lacunar infarcts and enlarged Virchow-Robin spaces. Therefore, we developed a computer-aided detection (CAD) scheme for the detection of lacunar infarcts. Although our previous CAD method indicated a sensitivity of 96.8 % with 0.71 false positives (FPs) per slice, further reduction of FPs remained an issue for the clinical application. Thus, the purpose of this study is to improve our CAD scheme by using template matching in the eigenspace. Conventional template matching is useful for the reduction of FPs, but it has the following two pitfalls: (1) It needs to maintain a large number of templates to improve the detection performance, and (2) calculation of the cross-correlation coefficient with these templates is time consuming. To solve these problems, we used template matching in the lower dimension space made by a principal component analysis. Our database comprised 1,143 T1- and T2-weighted images obtained from 132 patients. The proposed method was evaluated by using twofold cross-validation. By using this method, 34.1 % of FPs was eliminated compared with our previous method. The final performance indicated that the sensitivity of the detection of lacunar infarcts was 96.8 % with 0.47 FPs per slice. Therefore, the modified CAD scheme could improve FP rate without a significant reduction in the true positive rate. 相似文献
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Shigeyuki Asano Takao Muramatsu Hiromu Kanno Haruki Wakasa 《Pathology international》1987,37(7):887-900
Dermatopathic lymphadenopathy (DPL) is characterized by lymph node enlargement with reactive process and is generally caused by chronic inflammatory skin disease. Interdigitating reticulum cells (IDCs) with broad cytoplasm, innumerable cytoplasmic interdigitation, and bizarre shaped nuclei are the most striking cell type in DPL. According to the shape of the nucleus, arrangement of the tubulovesicular complexes (TVC) and amount of melanin granules, these cells fall into two types: type I has a marked indented nucleus, innumerable TVC and some desmosomal junctions and fewer melanin granules, while type II has a large amount of melanin granules. On the other hand, LCs contain a few loose melanin granules. It appears that IDCs and Langer-hans cells (LCs), surrounded by T-lymphocytes, are similar in morphology and function, but both of them can be characterized by the positive of S-100 protein and Leu 6, absence of lysozymes and CEA by PAP method, and positive of ATP-ase and ACP-ase, and they differ only by having or not having Birbeck granules. The mechanism of the proliferation of IDCs in DPL and delineation of the functional relationship between the accessory cells and the T-lymphocytes remains to be investigated. ACTA PATHOL. JPN. 37:887–900, 1987. 相似文献
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Genetic heterogeneity of uncharacterized childhood autoimmune diseases with lymphoproliferation 下载免费PDF全文
Masatoshi Takagi Akihiro Hoshino Kenichi Yoshida Hiroo Ueno Kohsuke Imai Jinhua Piao Hirokazu Kanegane Motoi Yamashita Tsubasa Okano Hideki Muramatsu Yusuke Okuno Yuichi Shiraishi Kenichi Chiba Hiroko Tanaka Satoru Miyano Seishi Ogawa Yasuhide Hayashi Seiji Kojima Tomohiro Morio 《Pediatric blood & cancer》2018,65(2)
Autoimmune diseases in children are rare and can be difficult to diagnose. Single causative genes have been identified for some pediatric autoimmune diseases. Such orphan diseases may not be diagnosed properly due to the variability of patients' phenotypes. Guidelines for the diagnostic process need to be developed. Fifteen patients with uncharacterized childhood autoimmune diseases with lymphoproliferation that had negative testing for autoimmune lymphoproliferative syndrome were subjected to whole‐exome sequencing to identify genes associated with these conditions. Five causative genes, CTLA4, STAT3, TNFAIP3, IKZF1, and PSTPIP1, were identified. These genes should be considered as candidates for uncharacterized childhood autoimmune diseases with lymphoproliferation. 相似文献
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Koji Kato Hirotoshi Sakaguchi Hideki Muramatsu Yuko Sekiya Nozomu Kawashima Atsushi Narita Sayoko Doisaki Nobuhiro Watanabe Nao Yoshida Kimikazu Matsumoto 《Pediatric transplantation》2018,22(2)
In SCT, death from transplant‐related complications is the major obstacle hindering improvement of transplant outcomes, and proper supportive care is essential to reduce TRM. The transplant outcomes of 210 pediatric patients with malignant and non‐malignant disorders who consecutively underwent SCT in our institution from 2000 to 2013 were analyzed. The transplant years were divided into three periods: A (2000‐2004), B (2005‐2008), and C (2009‐2013), and an improvement in 5‐year OS and a decrease in 5‐year TRM were observed over these time periods; that is, OS was 61.5%, 60.3%, and 79.5% (P = .062), and TRM was 19.9%, 7.9%, and 0.0% (P < .001) in periods A, B, and C, respectively. On multivariate analysis, the prognostic factor for TRM for all patients was administration of danaparoid (HR = 0.109, 95% CI = 0.033‐0.363, P < .001), and for patients with hematological malignancies in allogeneic SCT, the prognostic factors were danaparoid (HR = 0.046, 95% CI = 0.006‐0.326, P = .002) and advanced disease at SCT (HR = 4.802, 95% CI = 1.734‐13.30, P = .003). A reduction in TRM after SCT was observed over the time periods, and supportive care with danaparoid was found to be significantly effective in reducing TRM in SCT for children. 相似文献
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