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1.
Hidenori Endo Chikako Nito Hiroshi Kamada Tatsuro Nishi Pak H Chan 《Journal of cerebral blood flow and metabolism》2006,26(12):1479-1489
Recent studies have revealed that the phosphatidylinositol 3-kinase (PI3-K) pathway is involved in apoptotic cell death after experimental cerebral ischemia. The serine-threonine kinase, Akt, functions in the PI3-K pathway and prevents apoptosis by phosphorylation at Ser473 after a variety of cell death stimuli. After phosphorylation, activated Akt inactivates other apoptogenic factors, including glycogen synthase kinase-3beta (GSK3beta), thereby inhibiting cell death. However, the role of Akt/GSK3beta signaling in the delayed death of hippocampal neurons in the CA1 subregion after transient global cerebral ischemia (tGCI) has not been clarified. Transient global cerebral ischemia for 5 mins was induced by bilateral common carotid artery occlusion combined with hypotension. Western blot analysis showed a significant increase in phospho-Akt (Ser473) and phospho-GSK3beta (Ser9) in the hippocampal CA1 subregion after tGCI. Immunohistochemistry showed that expression of phospho-Akt (Ser473) and phospho-GSK3beta (Ser9) was markedly increased in the vulnerable CA1 subregion, but not in the ischemic-tolerant CA3 subregion. Double staining with phospho-GSK3beta (Ser9) and terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end labeling showed different cellular distributions in the CA1 subregion 3 days after tGCI. Phosphorylation of Akt and GSK3beta was prevented by LY294002, a PI3-K inhibitor, which facilitated subsequent DNA fragmentation 3 days after tGCI. Moreover, transgenic rats that overexpress copper/zinc-superoxide dismutase, which is known to be neuroprotective against delayed hippocampal CA1 injury after tGCI, had enhanced and persistent phosphorylation of both Akt and GSK3beta after tGCI. These findings suggest that activation of the Akt/GSK3beta signaling pathway may mediate survival of vulnerable hippocampal CA1 neurons after tGCI. 相似文献
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We examined the effects of dopamine (DOA) 10 μg·kg−1·min−1 I.V. and dobutamine (DOB) 10 μg·kg−1. min−1 I.V. on the contractility of the fatigued diaphragm in 26 anesthetized, mechanically ventilated dogs. Animals were divided
into two groups of 13 each: the DOA and DOB groups. Diaphragmatic fatigue was induced by intermittent supramaximal bilateral
electrophrenic stimulation at a frequency of 20 Hz applied for 30 min. Diaphragmatic contractility was assessed from changes
in transdiaphragmatic pressure (Pdi). After diaphragmatic fatigue, Pdi at low-frequency (20 Hz) stimulation decreased significantly compared with the prefatigue value (P<0.05), whereas no change in Pdi was observed at high-frequency (100 Hz) stimulation. In the fatigued diaphragm, Pdi at both stimuli increased with an infusion of either DOA (P<0.05) or DOB (P<0.05). The increase of Pdi at 20 Hz stimulation was significantly larger in the DOB group compared with that of the DOA group (P<0.05). In each group, Pdi at both stimuli decreased after the cessation of administration. The integrated diaphragmatic electric activity (Edi) in the two groups did not change at any frequency of stimulation throughout the study. We conclude that DOB in comparison
with DOA is more effective in improving the contractility of the fatigued diaphragm. 相似文献
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Accumulated evidence from a number of previous structural MRI studies have revealed 1) the existence of abnormalities even at the brain structural level in subjects at an early stage of endogeneous psychotic illness, including schizophrenia and bipolar disorder, and 2) the existence of similar brain structural abnormalities to the patients even in individuals at high-risk of endogeneous psychotic illness. Recently, an increasing number of studies have investigated the associations between the functional polymorphism of candidate genes for susceptibility to schizophrenia and regional brain volume, a highly heritable trait marker, to uncover the linkage between the candidate genes and endophenotype of schizophrenia. Firstly, this review article overviewed recent literature examining the relationship between the candidate genes for susceptibility to schizophrenia and indices obtained from neuroimaging modalities. In contrast, a relatively limited number of previous studies examined associations between candidate genes for susceptibility to bipolar disorder and regional brain volume, although the high heritability of bipolar disorder has been reported as comparable to that of schizophrenia. Then, we discussed the possibility of endophenotyping of bipolar disorder and introduced our preliminary study. Finally, methodological considerations and future directions of endophenotyping of endogeneous psychosis were suggested. 相似文献
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Isao Kurosaki Kazuhiro Tsukada Hidenori Ueki Akira Ohya Katsuyoshi Hatakeyama 《Journal of Hepato-Biliary-Pancreatic Surgery》1997,4(1):131-134
We report a case of advanced gallbladder cancer in a 37-year-old man who presented in June 1993 with malignant obstructive jaundice. After percutaneous transhepatic biliary drainage and several diagnostic imaging examinations, the patient underwent laparotomy under a diagnosis of extremely advanced gallbladder cancer involving the confluence of the hepatic ducts. The tumor, however, was judged to be unresectable because of its massive spread into the liver along Glisson's sheath, and because of histologically proven peritoneal dissemination. After exploratory laparotomy, one course of anticancer chemotherapy (cisplatin, 100 mg/body IV, on day 1, and 5-fluorouracil, 1000 mg/body, on days 1–5, by continuous infusion) was administered and the completely obstructed hepatic duct was dramatically re-canalized. Four courses of chemotherapy were administered over a 16-month period until jaundice recurred. For these 16 months, the patient's quality of life was well maintained without biliary drainage. He died of increased peritoneal dissemination approximately 2 years after the first course of anticancer chemotherapy. 相似文献
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Gou Takeo Masakatsu Motomura Hidenori Matsuo Kiyosumi Ohishi Toshiro Yoshimura Shigenobu Nagataki Mitsuhiro Tsujihata 《Muscle & nerve》1993,16(8):840-848
We investigated the effect of the lgG from patients with myasthenia gravis (MG) on the degradation of normal rat junctional acetylcholine receptor (AChR) labeled with 125l-α-bungarotoxin (BuTx) and calculated the degradation rate (DR). The DR for the lgG from these patients was significantly higher than that from healthy volunteers and patients with other autoimmune diseases. For MG, DR was significantly correlated with the severity of the disease but not with anti-AChR antibody titer. DR was accelerated by lgG from patients with generalized MG whose antibody titers were in the normal range and by lgG from patients with ocular MG. These results indicate that measurement of the DR of junctional AChR in normal rats is more closely correlated with the severity of the disease than is measurement of anti-AChR antibody and that the former is a sensitive and confirmatory method for evaluating MG. © 1993 John Wiley & Sons, Inc. 相似文献
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Ito Y Yoshida H Tomoda C Miya A Kobayashi K Matsuzuka F Yasuoka H Kakudo K Inohara H Kuma K Miyauchi A 《Pathology》2005,37(4):296-298
AIMS: Galectin-3, a member of the beta-galactoside binding family of lectins, has been regarded as a useful tool for discriminating malignant tumours from benign nodules of the thyroid, including the distinction between follicular carcinoma and adenoma. However, there are follicular tumours with unclear vascular or capsular invasion, which makes diagnosis more difficult. In this study, we investigated the relationship between galectin-3 expression and the degree of vascular or capsular invasion of follicular tumours. METHODS: We immunohistochemically investigated galectin-3 expression in 260 cases of follicular tumour with various degrees of vascular or capsular invasion classified into four categories. RESULTS: The galectin-3 expression level significantly increased with the degree of vascular or capsular invasion (p<0.0001). However, its diagnostic value for follicular carcinoma was not high because the sensitivity and specificity were 68.7% and 57.5%, respectively. CONCLUSIONS: Our findings suggest that galectin-3 plays a role in the transformation of follicular tumours from benign to malignant; however, when diagnosing follicular tumours, the presence of this protein should not be required for diagnosing malignant transformation in all cases. Therefore, we must conclude that galectin-3 should only be considered an adjuvant marker for follicular carcinoma. 相似文献