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41.
Shizuo Oi Mitsunori Matsumae Futoshi Takei Masaki Shinoda Osamu Sato Satoshi Matsumoto 《Child's nervous system》1996,12(5):242-247
The process of the development of the intracranial vessels was studied by means of immunohistochemical analysis of factor VIII in normal and exencephalic chick fetuses. The results revealed that the development of blood vessels in exencephalic brain was far advanced beyond the norm, with intense immunoreactivity to factor VIII on postincubation day 16 exceeding that on day 21 in normal controls. Compared with results regarding the direction of the overgrowth in the neuronal maturation process in the previous study using the chick exencephaly model, the findings of overmatured blood vessels were compatible with NSE- and somatostatin-positive elements that appeared especially in the overgrowth foci. The results of the present study suggested the pathogenic development of the area cerebrovasculosa in the neural placode as a phenomenon consequent upon hypervascularization in response to neuronal overgrowth, as seen in human cases of exencephaly or anencephaly. We emphasize the significance of this specific phenomenon in the development of the fetal central nervous system, namely neurovascular developmental interaction. 相似文献
42.
Shin-ichi Hirano Naoki Agata Yutaka Hara Hiroshi Iguchi Masataka Shirai Hiroshi Tone Norimoto Urakawa 《Cancer chemotherapy and pharmacology》1991,28(4):266-272
Summary In the present study we examined the effects of pirarubicin [(2R)-4-0-tetrahydropyranyladriamycin, THP] on a cardiovascular system. An injection of THP (0.39–3.13 mg/kg, i. v.) reduced the mean blood pressure and caused an increase in the respiratory air rate in anesthetized rats. At 1.5×10–6–1.5×10–5
m, THP markedly relaxed a contraction induced by 10–7
m norepinephrine in rat aorta with endothelium but not in that without endothelium. At a dose of 0.02–0.5 mg, THP produced an increase in the contractile force and the perfusion flow of isolated perfused guinea pig hearts. At a higher concentration (4.5×10–5–1.5×10–4
m), it produced a slight increase in the contractile force of the left atria in guinea pigs. This positive inotropic action of THP was inhibited by diphenhydramine (10–6–5×10–5
m), chlorpheniramine (3×10–7–3×10–5
m), and tripelennamine (3×10–7–3×10–5
m) but not by propranolol (10–6
m), cimetidine (10–5
m), diltiazem (10–6
m), or ryanodine (10–8
m). THP given i. v. at 2.5 mg/kg elevated the plasma histamine level in anesthetized dogs. From these data, we conclude that THP mainly relaxed the rat aorta in the presence of endothelium and that at higher concentrations, it increased the contractile force in the cardiac muscle, probably mediated through the release of histamine. 相似文献
43.
Nobuyuki Enomoto Yoshiyuki Takei Kazuyoshi Kon Shunhei Yamashina Satoko Suzuki Kenichi Ikejima Nobuhiro Sato 《Nihon Arukōru Yakubutsu Igakkai zasshi》2005,40(3):213-218
The hepatotoxic effects of alcohol have been described in detail, but factors responsible for its hepatotoxicity have only partially characterized. It now appears that Kupffer cell derived TNF-alpha participates in several aspects of alcoholic liver injury. On the other hand, protease inhibitors have been used successfully for treatment of intractable diseases in which TNF-alpha is involved in the pathogenesis, including ulcerative colitis and Crohn's disease. Here, we will review new evidence for the proposal that serine protease inhibitors prevents alcoholic liver injury via mechanisms dependent on Kupffer cell derived TNF-alpha. 相似文献
44.
Shin-ichi Fukumoto Naoko Yamauchi Hisashi Moriguchi Yoshitaka Hippo Akira Watanabe Junji Shibahara Hirokazu Taniguchi Shumpei Ishikawa Hirotaka Ito Shogo Yamamoto Hiroko Iwanari Mitsugu Hironaka Yuichi Ishikawa Toshiro Niki Yasunori Sohara Tatsuhiko Kodama Masaharu Nishimura Masashi Fukayama Hirotoshi Dosaka-Akita Hiroyuki Aburatani 《Clinical cancer research》2005,11(5):1776-1785
PURPOSE: Squamous cell carcinoma (SCC) and adenocarcinoma of the lung are currently subject to similar treatment regimens despite distinct differences in histology and epidemiology. The aim of this study is to identify a molecular target with diagnostic and therapeutic values for SCC. EXPERIMENTAL DESIGN: Genes specifically up-regulated in SCC were explored through microarray analysis of 5 SCCs, 5 adenocarcinomas, 10 small cell lung carcinomas, 27 normal tissues, and 40 cancer cell lines. Clinical usefulness of these genes was subsequently examined mainly by immunohistochemical analysis. RESULTS: Seven genes, including aldo-keto reductase family 1, member B10 (AKR1B10), were identified as SCC-specific genes. AKR1B10 was further examined by immunohistochemical analysis of 101 non-small cell lung carcinomas (NSCLC) and its overexpression was observed in 27 of 32 (84.4%) SCCs and 19 of 65 (29.2%) adenocarcinomas. Multiple regression analysis showed that smoking was an independent variable responsible for AKR1B10 overexpression in NSCLCs (P < 0.01) and adenocarcinomas (P < 0.01). AKR1B10 staining was occasionally observed even in squamous metaplasia, a precancerous lesion of SCC. CONCLUSION: AKR1B10 was overexpressed in most cases with SCC, which is closely associated with smoking, and many adenocarcinoma cases of smokers. These results suggest that AKR1B10 is a potential diagnostic marker specific to smokers' NSCLCs and might be involved in tobacco-related carcinogenesis. 相似文献
45.
Kiyokazu Takebayashi Yoshimoto Sekine Nori Takei Yoshio Minabe Haruo Isoda Hiroyasu Takeda Katsuhiko Nishimura Kazuhiko Nakamura Katsuaki Suzuki Yasuhide Iwata Harumi Sakahara Norio Mori 《Neuropsychopharmacology》2004,29(5):1019-1026
Long-term toluene abuse causes a variety of psychiatric symptoms. However, little is known about abnormalities at the neurochemical level in the living human brain after long-term exposure to toluene. To detect neurochemical changes in the basal ganglia of subjects with a history of long-term toluene use, proton magnetic resonance spectroscopy (1H MRS) was performed in 12 abstinent toluene users and 13 healthy comparisons with no history of drug abuse. N-acetylaspartate (NAA), creatine plus phosphocreatine (Cr + PCr), choline-containing compounds (Cho), and myo-inositol (MI) levels were measured in the left and right basal ganglia. The Cho/Cr + PCr ratio, a marker of membrane metabolism, was significantly increased in the basal ganglia of toluene users in comparison to that of the control subjects. Furthermore, the increase in the Cho/Cr + PCr ratio was significantly correlated with the severity of residual psychiatric symptoms. These findings suggest that long-term toluene use causes membrane disturbance in the basal ganglia, which is associated with residual psychiatric symptoms that persist even after long-term abstinence from toluene use. 相似文献
46.
Gender difference in alcoholic liver injury] 总被引:1,自引:0,他引:1
Nobuyuki Enomoto Yoshiyuki Takei Shunhei Yamashina Kenichi Ikejima Satoko Suzuki Tsuneo Kitamura Nobuhiro Sato 《Nihon Arukōru Yakubutsu Igakkai zasshi》2004,39(3):163-167
Gender differences of alcoholic liver injury have been described previously, but mechanisms have only partially characterized. For example, it is known that females develop alcoholic liver injury more rapidly and to a greater extent than males. It now appears that estrogen participates in several aspects of this phenomenon. On the other hand, attention has been directed towards the effect of ethanol ingestion on Kupffer cell function, which is stimulated by gut-derived endotoxins via mechanisms dependent on increased gut permeability and the possible relationship between Kupffer cell and alcohol-induced liver injury. 相似文献
47.
土槿皮乙酸体外诱导A375-S2细胞凋亡 总被引:6,自引:1,他引:6
目的 :研究土槿皮乙酸 (pseudolaricacidB)诱导A375 S2细胞凋亡的作用 ,探讨其抗癌作用机制。方法 :采用噻唑蓝 (MTT)法、形态学观察、DNA凝胶电泳及Westernblot检测法。结果 :土槿皮乙酸可剂量 时间依赖性的诱导A375 S2细胞凋亡 ,5 μmol·L-1土槿皮乙酸处理 36h的细胞 ,Hoechst 332 5 8荧光染色后有明显的凋亡小体出现 ;凝胶电泳法显示有明显的DNAladder出现。细胞内抑制凋亡蛋白Bcl 2 ,Bcl xL和caspase激活的DNA酶抑制物(ICAD)表达量时间依赖性地减少 ,而促凋亡蛋白Bax表达量增加。结论 :土槿皮乙酸对A375 S2细胞的杀伤作用主要通过诱导细胞凋亡 ,降低Bcl 2 ,Bcl xL和ICAD蛋白的表达 ,增加Bax蛋白表达为其诱发A375 S2细胞凋亡的机制之一。 相似文献
48.
49.
Qiong Wang Miao Liu Wei-Wei Liu Wen-Bo Hao Shin-ichi Tashiro Satoshi Onodera 《Journal of Asian natural products research》2013,15(5):413-423
Improper adjustments of autophagy and silent information regulator 1 (Sirt-1) expression were reported to be closely associated with metabolic disorders. In this study, we examined the roles of Sirt-1 and autophagy in streptozotocin-induced diabetes mellitus, assessed the relationship between autophagy and Sirt-1, and investigated the protective mechanism of silibinin. Diabetes was induced in 6-week-old mice by intravenous injection of streptozotocin (150 mg/kg/day, for 2 weeks). In the treatment groups, silibinin (50 mg/kg/day, intramuscular injection, for 8 weeks) or inhibitors (50 mg/kg/day, subcutaneous injection, for 8 weeks) were given. Diabetic control animals received vehicle for the same time. Compared with diabetic controls, silibinin or autophagy inhibitor, 3-methyladenine, treated mice showed decreased levels of glycosylated hemoglobin A1C (P < 0.01), serum triglyceride (P < 0.01), cholesterol (P < 0.01), blood glucose (P < 0.05), autophagy (P < 0.05), and apoptosis ratio (P < 0.05) of pancreatic β-cells. Systemic administration of silibinin reversed streptozotocin-induced downregulation of Sirt-1 expression. Sirt-1 may play a role in regulating the physiological level of autophagy and is associated with loss of pancreatic β-cells and metabolic biochemical disorders. Through promoting Sirt-1 expression and recovering autophagy physiologically, silibinin may reverse hyperglycemia and repair damaged pancreatic β-cells. 相似文献
50.
目的水飞蓟素和CH11共同作用诱导人黑色素瘤细胞A375-S2凋亡的分子机制。方法结晶紫法测定细胞生长抑制率;细胞凋亡的形态学观察,LDH法测定凋亡与坏死的比率;用免疫印迹法检测凋亡抑制性的去乙酰化酶SIRT1、Bc l-2家族成员(抗凋亡蛋白Bc l-2,Bc l-xL和促凋亡蛋白Bax)、细胞色素C和Caspase-3的表达。结果水飞蓟素和CH11共同作用能诱导A375-S2细胞发生凋亡;形态学观察可见凋亡小体的形成;免疫印迹法检测发现水飞蓟素和CH11共同作用的A375-S2细胞中Bax蛋白的表达增加,Bc l-2蛋白和Bc l-xL蛋白的表达降低,细胞色素C释放增加,pro-caspase-3表达量明显降低。结论水飞蓟素协同CH11能明显促进A375-S2细胞的凋亡。 相似文献