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Kazuo Kitagawa Masayasu Matsumoto Keisuke Kuwabara Masafumi Tagaya Toshiho Ohtsuki Ryuji Hata Hirokazu Ueda Nobou Handa Kazufumi Kimura Takenobu Kamada 《Brain research》1991,561(2)
We investigated the effects of mild and non-lethal ischemic insult on neuronal death following subsequent lethal ischemic stress in various brain regions, using a gerbil model of bilateral cerebral ischemia. Single 10-min ischemia consistently caused neuronal damage in the hippocampal CA1, CA2, CA3 and CA4, layer III/IV of the cerebral cortex, dorsolateral part of the caudoputamen and ventrolateral part of the thalamus. On the other hand, in double ischemia groups, 2-min ischemic insult 2 days before 10-min ischemia exhibited significant protection in the CA1 and CA3 of the hippocampus, the cerebral cortex, the caudoputamen and the thalamus. Five-min ischemic insult 2 days before 10-min ischemia also showed protective effect in the same areas as those of 2-min ischemia except for the CA1 region of the hippocampus, while 1-min ischemic insult exhibited no protective effect in any brain regions. In the immunoblot analysis, both 2- and 5-min ischemia caused increased synthesis of heat shock protein 72 (HSP 72) in the hippocampus, but 1-min ischemia did not. The present study demonstrated that the ‘ischemic tolerance’ phenomenon was widely found in the brain and also suggested that ischemic treatment severe enough to cause HSP 72 synthesis might be needed for induction of ‘ischemic tolerance’. 相似文献
23.
Takahide Nagashima Hideaki Tanaka Masafumi Ito Koichi Hirata Soichi Katayama Kazuo Watanabe 《Clinical neurology》2006,46(1):40-44
We report a patient of relapsing polychondritis (RP) with antecedent aseptic meningitis. A 65-year-old man has developed headache and fever. Neurological examination showed meningeal signs, and cerebrospinal fluid (CSF) examination revealed meningeal inflammation which contained 450 polymorphonuclear cells/microl, 302 mononuclear cells/microl, and 0 red cells/microl, with 79 mg protein/dl. Serologic testing for autoimmune disease as well as the culture and cytology of CSF were negative. He admitted our hospital as having aseptic meningitis and experienced antibiotic therapy. However, his pyrexia continued and he developed repeating visual and hearing impairment reacting to steroid. Three months later, he became behaviorally deaf, and bilateral auricular chondritis occurred with nonerosive seronegative inflammatory polyarthritis. The result of condral biopsy was consistent with the diagnosis of RP showing cartilage surrounded by an intense inflammatory cell response with a decreased number of chondrocytes. A clinical diagnosis was made and prednisolone 60 mg/day was begun with the result of resolution of the auricular chondritis, and slight improvement of his deafness. Aseptic meningitis is a rare complication of RP. Only one report detailed RP patient who had preceding meningitis. RP is a potentially lethal disease resulting from suffocation by airway collapse, the complications of a cardiac large vessel, and so on. For improvement of a life prognosis, an early diagnosis and treatment are indispensable. Although RP is a rare discovery, it is necessary that RP should be taken into consideration and be differentiated as a cause of relapsing aseptic meningitis. 相似文献
24.
We measured plasma heparin cofactor II (HC II) activity in patients with disseminated intravascular coagulation (DIC) due to various underlying diseases together with the levels of antithrombin III (AT III), pseudocholinesterase (a marker of hepatic synthesis), and various haemostatic molecular markers. Both HC II and AT III were decreased in DIC secondary to all the underlying diseases studied, except acute promyelocytic leukemia (APL), when compared with healthy subjects. The lowest HC II and AT III levels was observed in coagulopathy secondary to liver disease, the HC II level in sepsis was the second lowest. In DIC due to APL, the decrease in HC II was not accompanied by a decrease in AT III. Thus, we divided all 124 samples tested into APL and non-APL groups. The HC II level correlated positively with fibrinogen and plasminogen in both the APL and non-APL groups. In the APL group, the HC II level had a significant negative correlation with the thrombin-AT III complex (TAT), fibrinogen/fibrin degradation products, and D-dimer levels as well as the prothrombin time, while AT III showed no correlations with any of the haemostatic parameters. These results suggest that HC II may be consumed preferentially by thrombin in APL patients with DIC, and thus may spare the consumption of AT III. Accordingly, HC II seems to be a superior indicator of DIC than AT III in APL patients. Moreover, replacement therapy with HC II instead of AT III may be useful to treat DIC associated with APL. In the non-APL group, the HC II levels were positively correlated with the levels of AT III and pseudocholinesterase activity. This indicates that plasma HC II levels are closely related not only to consumption coagulopathy but also to hepatic synthetic activity, as is the case for plasma AT III. 相似文献
25.
Takashi Murakami Hitoshi Horigome Kiyoji Tanaka Yoshio Nakata Yasutomi Katayama Akira Matsui 《Blood coagulation & fibrinolysis》2007,18(5):389-394
Obesity is a risk factor for cardiovascular disease and thromboembolic events. We investigated the effects of weight reduction by a 12-week calorie-restricted diet with or without aerobic exercise (diet group and diet plus exercise group) on leptin and anticoagulation proteins levels. Forty-two obese nondiabetic individuals were evaluated for blood levels of leptin, protein C activity, free protein S antigen and for body fat area calculated on computerized tomography before and after intervention. Before intervention, serum levels of leptin and free protein S antigen correlated positively with several adiposity-related parameters. After the program, body weight and fat area were significantly decreased in both groups. Body mass index and leptin levels decreased in both groups, with a larger change in the diet plus exercise group than in the diet group. Although protein C activity levels did not change in both groups, free protein S antigen levels decreased significantly in the diet plus exercise group. In conclusion, the 12-week programs had significant effects on the initial weight reduction and body fat mass, decreasing lepin levels in obese nondiabetic individuals. To clarify whether aerobic exercise has additional or direct effects on the anticoagulation system, a study in a large number of individuals is needed. 相似文献
26.
Tomomi Iwashita Kazuo Kitazawa Jun-Ichi Koyama Hisashi Nagashima Toru Koyama Yuichiro Tanaka Kazuhiro Hongo Hiroshi Okudera Kazufumi Okamoto 《Journal of clinical neuroscience》2007,14(1):68-71
A patient with cerebral deep sinus thrombosis, which was not diagnosed on the first examination, is reported. A 46-year-old woman presented with headache and vomiting. Neurological examination and a brain computed tomography (CT) scan showed no obvious abnormal findings. The patient suffered disturbed consciousness on the day after the examination, and was admitted to our emergency centre. A CT scan and magnetic resonance imaging revealed an ischaemic lesion in the left basal ganglia, suggesting deep sinus occlusion. Anticoagulant therapy was administered. One day after admission, a CT scan showed a haematoma and severe brain swelling in the same region. Cerebral angiography demonstrated a straight sinus occlusion. Intracranial pressure was not controlled with hypothermia, and the patient died 25 days after admission. Review of the initial CT scan revealed subtle, early findings of deep venous thrombosis that were missed on first examination. 相似文献
27.
Yuji Katayama Naoki Minato Masayuki Sakaguchi Atsushi Nakashima Kazuhiro Hisajima 《Annals of thoracic and cardiovascular surgery》2005,11(6):419-423
Pseudoaneurysm is an uncommon and serious complication of infective endocarditis (IE). It is often fatal because of its rapid progress, high rates of rupture and recurrence, and worsening effects on the systemic condition. We report the rare case of a patient who developed a pseudoaneurysm of the sinus of Valsalva two months after emergency aortic valve replacement for active IE. At the previous operation, we had directly closed a small fistulous hole in the non-coronary sinus of Valsalva using two mattress sutures with autologous pericardial pledgets, because the tissue surrounding the hole did not appear to be infected on visual inspection. A pseudoaneurysm developed from this portion due to detachment of sutures. If the fistula had been completely resected during the first surgery instead of performing a simple closure, the pseudoaneurysm of the sinus of Valsalva would not have formed. However, the primary aim of the first emergency surgery was to spare the life of a critically ill patient. In the second surgery, the pseudoaneurysm was completely resected with the aortic wall--including the non-coronary sinus of Valsalva and the communicating hole. Then, patch plasty of the non-Valsalva sinus was successfully performed. 相似文献
28.
Movement of the lateral and medial poles of the working condyle during mastication in patients with unilateral posterior crossbite. 总被引:1,自引:0,他引:1
Shouichi Miyawaki Yuko Tanimoto Yoshiko Araki Akira Katayama Takuo Kuboki Teruko Takano-Yamamoto 《American journal of orthodontics and dentofacial orthopedics》2004,126(5):549-554
Patients with unilateral posterior crossbite often show reverse sequential jaw movement patterns on the frontal view during mastication on the crossbite side. Recent studies show that such patients are prone to suffer from temporomandibular joint (TMJ) disc displacement, particularly the lateral portion. The purpose of this study was to examine the movement of the lateral and medial poles of the working condyle during mastication in such patients. Subjects were 12 consecutive patients with unilateral posterior crossbites and without TMJ disc displacements and 12 normal subjects. An optoelectronic jaw-tracking system with 6 degrees of freedom was used to record the motion of the lateral and medial poles of the working condyle during mastication of standardized hard, gummy jelly. The data from the first 10 cycles were analyzed. The lateral and medial poles of the condyle on the crossbite side moved more in the medial direction and less in the lateral direction during mastication in the crossbite patients than the condyle in the normal subjects. The lateral pole of the working condyle moved more in the posterior and inferior directions and less in the anterior direction than the medial pole in all subjects. These results suggest that these condylar movements in patients with unilateral posterior crossbites might be related to the susceptibility to TMJ disc displacement, particularly the lateral portion. 相似文献
29.
Takafumi Nagaoka Yoichi Katayama Toshikazu Kano Kazutaka Kobayashi Hideki Oshima Chikashi Fukaya Takamitsu Yamamoto 《Neuromodulation》2007,10(3):206-215
Objective. Employing [18F]fluorodeoxyglucose (FDG) positron emission tomography (PET) to assess the correlation between the effect of deep brain stimulation (DBS) on the subthalamic nucleus (STN) and the regional cerebral metabolic rate of glucose (rCMRGlc) in advanced Parkinson's disease patients (N = 8). Materials and Methods. On the basis of patients’ diary records, we performed FDG‐PET during the off‐period of motor activity with on‐ or off‐stimulation by STN‐DBS on separate days and analyzed the correlation between changes in motor symptoms and alterations in the rCMRGlc. Result. When FDG‐PET was performed, the motor score on the unified Parkinson's disease rating scale (UPDRS) was 64% lower with on‐stimulation than with off‐stimulation (p < 0.001, Wilcoxon single‐rank test). STN‐DBS increased the rCMRGlc in the posterior part of the right middle frontal gyrus, which corresponded to the premotor area, and the right anterior lobe of the cerebellum (p < 0.005, paired t‐test). No region exhibited a decrease in rCMRGlc. Among the items of the UPDRS motor score, the changes in resting tremor and rigidity of the left extremities showed a significant correlation with the changes in rCMRGlc observed in the right premotor area (p < 0.02 and p < 0.05, respectively, Spearman's rank correlation). Conclusions. STN‐DBS either activates the premotor area or normalizes the deactivation of the premotor area. These FDG‐PET findings obtained are consistent with the idea that STN‐DBS modifies the activities of neural circuits involved in motor control. 相似文献
30.
T Oikawa K Hirotani H Ogasawara T Katayama O Nakamura T Iwaguchi A Hiragun 《European journal of pharmacology》1990,178(2):247-250
The effects of vitamin D3 and two analogues on embryonic angiogenesis were studied in 4.5-day-old chick embryo chorioallantoic membranes. The active metabolite of vitamin D3, 1 alpha,25-dihydroxyvitamin D3, and a synthetic vitamin D3 analogue, 22-oxa-1 alpha,25-dihydroxyvitamin D3, inhibited angiogenesis in a dose-dependent manner, the inhibition occurring in the picomolar range. In contrast, vitamin D3 was not effective. The results suggest that these two vitamin D3 analogues might be promising anti-angiogenic agents for controlling the angiogenesis which occurs in several pathological conditions, including tumor development. 相似文献