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31.
Kazumichi Yamada Satoshi Goto Taro Oyama Makoto Yoshikawa Shinji Nagahiro Yukitaka Ushio 《Acta neuropathologica》1995,89(2):172-177
The present study concerns the vulnerability of striatal interneurons immunopositive for the Ca2+-binding protein calretinin to ischemic neuronal injury. An immunohistochemical study was carried out on the striata of rats which had undergone transient middle cerebral artery occlusion. Two weeks after the ischemia, there was a marked reduction in the number of calretinin-positive neurons in the ipsilateral ischemic lesion, although the striatal interneurons positive for parvalbumin, which are a neuronal population distinct from the calretinin-immunoreactive cells in the striatum, were spared in the insulted areas. The present data indicate that the striatal calretinin-positive neurons are less resistant to transient ischemia, suggesting that there may exist vulnerability differences among the striatal interneurons in ischemia-induced neuronal injury. 相似文献
32.
Satoshi Abe 《Journal of orthopaedic science》1997,2(2):75-83
The purpose of this study was to validate the hypothesis of neural histogenesis of Ewing's sarcoma of bone and related tumors
by light microscopic, electron microscopic, and immunohistochemical analysis. We studied 32 round-cell sarcomas (19 cases
of Ewing's sarcoma of bone, 3 extraskeletal Ewing's sarcomas, 5 peripheral primitive neuroectodermal tumors (PNET) and 5 cases
of unclassified small round-cell type of neurogenic sarcoma (NS). Immunoreactivity for MIC2 was observed in all cases of Ewing's
sarcoma and PNET, and in 1 cases of NS. Positive immunoreactivity for neural markers (NSE, synaptophysin, S-100) was found
frequently in some tumors. Ultrastructurally, some specific features of neural differentiation, such as a fragmented basal
lamina and neurosecretory granule-like particles, were found even in typical cases of Ewing's sarcoma of bone, which presented
without a rosette arrangement and were almost negative for neural immuno-markers, but positive for MIC2. These ultrastructural
neural features were observed less frequently in Ewing's sarcoma of bone than in PNET and NS. However, no significant correlation
was demonstrated between the immunoreactivity for neural markers and the ultrastructural and histological neural features.
These results support the hypothesis of a neural origin of Ewing's sarcoma and related neoplasms, and suggest that some overlapping
entity could persist in PNET and Ewing's sarcoma and that this entity could be seen in histological and immunohistochemical
studies of both tumors. 相似文献
33.
M. Nakamura Michitaka Ozaki Shohei Fuchinoue Satoshi Teraoka Kazuo Ota 《Transplant international》1997,10(2):89-95
Ischemia-reperfusion injury by free radicals and lipid peroxides is observed in various organs. Ascorbic acid (AsA) or glutathione
(GSH) in various doses (AsA:2, 0.5, 0.1 mmol/kg, GSH:2 mmol/kg) was intraperitoneally administered to male Wistar rats. The
entire small intestines were resected just before ischemia, after ischemia, and after 20 min of reperfusion (n = 7–10 at each time point). At each time point, the specimens were subjected to assays of lipid peroxides, GSH, and glutaminase
activity of the tissues; they were also examined histologically. In the AsA group, the production of lipid peroxides after
reperfusion was significantly suppressed in a dose-dependent manner, and the ratio of oxidized GSH to total GSH was also significantly
low. Tissue glutaminase activity decreased to a lesser extent, and the degree of injury was apparently less marked in the
AsA group. This study indicates that AsA acts as an antioxidant against peroxidative tissue injury, possibly by scavenging
radicals, preserving reduced GSH, and reducing the peroxidative reaction.
Received: 21 June 1996 Received after revision: 8 October 1996 Accepted: 12 November 1996 相似文献
34.
Hisao Komatsu Junko Nogaya Masaaki Ueki Satoshi Yokono Kenji Ogli 《Clinical and experimental pharmacology & physiology》1994,21(6):495-499
1. We previously reported that volatile anaesthetics produce incidences of a transient opisthotonus in mice, a sign of CNS stimulation. This study was performed to investigate mechanisms by which enflurane-induced opisthotonus (EIO) occurs. 2. The effects of pretreatment of N-methyl-d-aspartate (NMDA) antagonists dizocilpine (MK-801; DIZ) and ketamine (KET), GABAA antagonists picrotoxin (PIC), pentylenetetrazol (PTZ) and glycine antagonist strychnine (STR) on the incidence of EIO were determined. Prior to exposure to 2.0% enflurane in air, male ddN mice were given intraperitoneal injections of 0.2 mL saline (control), 0.5–5.0 mg/kg DIZ, 20–80 mg/kg KET, 2.9 mg/kg PIC, 40.0 mg/kg PTZ and 0.75 mg/kg STR. After the injection, the behavioural state of the mice was observed for 20 min (the pre-enflurane period). During the exposure to enflurane the time for immobilization, that is, anaesthetic induction time (IT), and the incidence of EIO were measured. 3. Dizocilpine (1.0–5.0 mg/kg) and KET (80 mg/kg) significantly (P<0.01) reduced both the incidence of EIO and IT in a dose-dependent manner. During the pre-enflurane period DIZ produced incidences (5–40%) of transient seizures in a dose-dependent manner, while KET did not induce them at all. The two GABAa antagonists had no detectable effect on the EIO. Strychnine significantly enhanced the EIO. These CNS stimulants resulted in a 3–10% incidence of transient seizure and/or opisthotonus during the pre-enflurane period, but there was no correlation between DIZ-induced seizure and EIO. 4. These results suggest that the EIO is mediated by the NMDA and the STR-sensitive glycine receptors, but not the GABAA receptor. We speculate that DIZ acts on the NMDA-receptor and/or disrupts the balance between the inhibitory and the excitatory systems. 相似文献
35.
Kiyoshi Nakatsuka Yoshiki Nishizawa Satoshi Hagiwara Hidenori Koyama Takami Miki Hironobu Ochi Hirotoshi Morii 《Calcified tissue international》1990,47(6):378-382
Summary Total body bone mineral (TBBM) content in rats was measured by dual photon absorptiometry (DPA). TBBM showed significant increases
over 4 weeks in control groups with significant bone loss over the same time in prednisolone-injected rats on low calcium
feed. Daily injections of calcitonin significantly reduced loss of bone mass. Both prednisolone- and prednisolone-calcitonin-injected
groups showed significantly elevated serum alkaline phosphatase with the prednisolone-calcitonin group also exhibiting elevated
serum calcium and phosphate levels, confirming the impact of the experimental protocol. TBBM measured by DPA in all groups
correlated well (r=0.928,P<0.001 n=20) with the total ash weight suggesting that the method reflects total skeletal mineral content in the small animal.
TBBM measurement by DPA proves well-suited to monitoring bone mineral in a small animal experimental setting. 相似文献
36.
Hideya Ohnishi Kazuyoshi Nishihara Keiyoshi Tamae Shoshu Mitsuyama Ryuji Abe Satoshi Toyoshima Eiji Abe 《Surgery today》1996,26(11):929-932
Granular cell tumors (GCT) are rare neoplasms, and only 173 cases of benign GCT of the breast have been documented. We report herein the cases of two patients with this tumor and discuss the methods of diagnosis and treatment. The first patient was a 60-year-old woman who presented with a firm ill-defined mass in her left breast. Mammography showed a dense shadow with spicula and skin thickness, and ultrasonography revealed a hypoechoic mass with an irregular border. Radical mastectomy was performed under the wrong preoperative diagnosis of breast cancer. The second patient was a 31-year-old woman who presented with an elastic-hard mass in her left breast. Mammography showed a well-demarcated dense mass, and ultrasonography revealed a well-defined hypoechoic mass with a large depth-width ratio. Fine-needle aspiration cytology (FNAC) showed a large number of histiocytic cells with abundant granular cytoplasm. An excisional biopsy was performed, and histological examination confirmed a diagnosis of GCT. GCT is benign, but often misdiagnosed as breast cancer both clinically and radiologically. Therefore, histological examination is essential for making a correct diagnosis, while FNAC is also useful. Local resection is still the treatment of choice, and surgeons should do their utmost to avoid performing needless radical mastectomy. 相似文献
37.
38.
Oral adsorbent (AST-120) reduces blood levels of urea and creatinine in experimental studies. It has also been shown to retard the progression of chronic renal failure in clinical studies. In the present study, the effect of AST-120 was examined in the rat model of subtotal nephrectomy (sNPX). This experimental model of chronic renal failure is characterized by glomerular hyperfunction, glomerular hypertrophy, increased mesangial trapment of macromolecules and subsequent glomerular sclerosis. We report the effect of AST-120 on glomerular hyperfunction, glomerular hypertrophy and mesangial trapment of macromolecules in the early stage and glomerular function and histology in the late stage of the rat model of sNPX. From 2 days after sNPX, rats were fed regular rat chow with (AST group: AST) or without (control) AST-120. At 2 weeks, iron dextran (ID) was injected intravenously. Three days after the injection, mesangial trapment of ID was largely ameliorated in AST when compared with control (p less than 0.02). The value of mean planar area of glomerulus (PAmean) in AST was significantly lower than that in control (p less than 0.05). At 2 and 9 weeks, the values of GFR and RPF in AST were all statistically higher than those in control. At 9 weeks, whereas average glomerular sclerosis index (SI: 0-4 scale) was 1.07 in control, significantly lower SI (0.57) was noted in AST (p less than 0.05). Thus, AST-120 has effects on glomerular hypertrophy, increased mesangial trapment of macromoleculus and finally the progression of chronic renal failure in the rat model of sNPX. The effects are not through reducing glomerular hyperfunction.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
39.
Dotlike Hemosiderin Spots Are Associated With Past Hemorrhagic Strokes in Patients With Lacunar Infarcts 总被引:1,自引:0,他引:1
Toshio Imaizumi MD PhD Toshimi Honma MD PhD Yoshifumi Horita MD Satoshi Iihoshi MD PhD Tatsufumi Nomura MD Kazuhisa Yoshifuji MD Jun Niwa MD PhD 《Journal of neuroimaging》2005,15(2):157-163
BACKGROUND AND PURPOSE: Dotlike hemosiderin spots ongradient-echo T2(*)-weighted magnetic resonance imaging of the brain have been histologically diagnosed as old microbleeds associated with small vessel disease (SVD). The authors hypothesize that the presence of many dotHSs may be correlated with the fragility of small vessels and the recurrence of SVD, including lacunar infarction and deep intracerebral hemorrhage (ICH). METHODS: To investigate how dotHSs are related to past history of SVD, the number of subcortical or deep dotHSs was investigated in 146 patients with lacunar infarctions (95 men, 51 women, age 38 to 90 [66.6+/-9.4] years). They were divided into 2 subgroups according to history of deep ICHs or lacunar infarctions. The odds ratio (OR) for past history was estimated from logistic regression analyses with the number of subcortical or deep dotHSs as well as other factors. RESULTS: Of 146 patients with lacunar infarctions, 11 had past symptomatic ICHs and 19 had past symptomatic lacunar infarctions. An elevated rate of history of ICH was found for lacunar infarction patients with many deep dotHSs (>or=3; OR, 9.1; 95% confidence interval, 1.6-51, P=.015). However, history of lacunar infarction was not significantly associated with the number of subcortical or deep dotHSs. CONCLUSIONS: Our findings suggest that many deep dotHSs on T2(*)-weighted magnetic resonance imaging may be correlated with deep ICH-lacunar infarction type of SVD recurrence but not lacunar infarction-lacunar infarction type. 相似文献
40.
Hang Zhao Takeshi Sugawara Shihiro Miura Tetsuya Iijima Satoshi Kashimoto 《Journal canadien d'anesthésie》2007,54(3):201-207
PURPOSE: The purpose of this study was to determine if intrathecal landiolol, a beta1-blocker, can modulate formalin-induced nociception and spinal c-Fos expression in mice, in the absence of anesthesia. METHODS: Thirty-two mice were randomly assigned to one of four groups: the control group (n = 8) received intrathecal normal saline 10 microL, while the other three groups (n = 8 for each) received intrathecal landiolol at escalating doses of 250 microg.kg(-1), 500 microg.kg(-1) and 750 microg.kg(-1) respectively, immediately after induction of anesthesia with isoflurane. After awakening, inflammatory pain was induced by 10 microL of 5% formalin solution injected into the dorsal surface of the right hind paw. The nociceptive behaviours including licking, biting and lifting of the injected paw were cumulatively recorded as seconds of behaviours/min during phase I (0-10 min) and phase II (10-45 min). The c-Fos protein expressions in the spinal dorsal horn were detected with immunohistochemical techniques in the control and landiolol 750 microg.kg(-1) groups. RESULTS: Compared to the control group, intrathecal injection of landiolol 750 microg.kg(-1) significantly decreased pain-related behaviours in phase I, while intrathecal landiolol 250 microg.kg(-1), 500 microg.kg(-1) and 750 microg.kg(-1) significantly decreased pain-related behaviours in phase II during the formalin test. The numbers of c-Fos immunoreactive nuclei in the L5 spinal dorsal horn were significantly lower in the landiolol 750 microg.kg(-1) group compared to the control group (landiolol 750 microg.kg(-1) 2.4 +/- 1.1 vs control 9.2 +/- 3.9; P < 0.01). CONCLUSION: The present study indicates that intrathecally administered landiolol produces significant antinociceptive effects in the formalin test. Although further studies exploring the detailed mechanism are needed, these data suggest a potential role of beta1-adrenoreceptors in spinal nociceptive processing. 相似文献