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PURPOSE: To clarify the appropriate concentration and dose of hypertonic saline solution (HSS) for preventing delayed neuronal death in the hippocampal CA1 subfield after transient forebrain ischemia in gerbils. METHODS: Thirty gerbils were randomly assigned to five groups: physiological saline solution (PSS) group, ischemia/reperfusion treated with PSS 2 mL x kg(-1); 5% HSS group, treated with 5% HSS 2 mL x kg(-1); 7.5% HSS group, treated with 7.5% HSS 2 mL x kg(-1); 10% HSS group, treated with 10% HSS 2 mL x kg(-1); 20% HSS group, treated with 20% HSS 2 mL x kg(-1). Transient forebrain ischemia was induced by occluding the bilateral common carotid arteries for four minutes. Five days later, histopathological changes in the hippocampal area were examined, and the degenerative ratio of the pyramidal cells were measured according to the following formula: (number of degenerative pyramidal cells/total number of pyramidal cells per 1 mm of hippocampal CA1 subfield) x 100. RESULTS: In PSS and 20% groups, neuronal cell damage was observed five days after ischemia. In the other three groups, these changes were not observed. The degenerative ratios of pyramidal cells were as follows; PSS group: 91.6 +/- 5.6%, 5% HSS group: 7.2 +/- 1.6%, 7.5% group: 8.3 +/- 1.4%, 10% HSS group: 6.2 +/- 1.1%, 20% HSS group: 85.8 +/- 8.7% (P < 0.05; PSS and 20% HSS vs three other groups). CONCLUSION: This study demonstrates that 5, 7.5 or 10% HSS 2 mL x kg(-1) may prevent delayed neuronal death in the hippocampal CA1 subfield after cerebral ischemia/reperfusion in gerbils.  相似文献   
3.
A left ventricular rupture due to embolic myocardial infarction is extremely rare. A 72-year-old woman developed an acute embolic myocardial infarction and mitral regurgitation due to infective endocarditis. Two days after the infarction, a left ventricular free wall rupture occurred after transesophageal echo examination. She received an epicardial patch and mitral valve replacement. Perioperatively, an intra-aortic balloon pump and long-term antibiotics were used. The postoperative course was uneventful, and she is doing well 10 months after surgery.  相似文献   
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To elucidate the mechanisms of the intracellular signal transduction elicited with bradykinin in NG108-15 neuroblastoma x glioma hybrid cells, we examined the activation of Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) by bradykinin stimulation. When the extract of NG108-15 cells was immunoprecipitated with the affinity-purified antibody to brain CaM kinase II, a 50-kDa protein in the immunoprecipitate mainly became autophosphorylated in a Ca2+/calmodulin-dependent manner. The results suggest that the 50-kDa protein is the subunit of CaM kinase II in NG108-15 cells. The Ca2+/calmodulin-independent activity (autonomous activity) of the enzyme increased twice within 10 s by stimulation with 1 microM bradykinin in the cells. The increase in the autonomous activity of the enzyme had two phases: the transient early-peak phase and the long late-plateau phase. The former was abolished by the pretreatment of the cells with 10 mM caffeine or 20 microM BAPTA-AM, and the latter was abolished by the removal of the extracellular Ca2+ with 1 mM EGTA or by the pretreatment with 1 microM nifedipine. Stimulation of 32P-labeled NG108-15 cells with 1 microM bradykinin increased the autophosphorylation of CaM kinase II and this increase was abolished by pretreatment with caffeine or BAPTA-AM. These results suggest that CaM kinase II is activated via the inositol phospholipid signaling pathway induced with bradykinin in NG108-15 cells.  相似文献   
6.
The reductive retention of62Cu-PTSM was comparatively studied in the brain and Ehrlich ascites tumor cells by electron spin resonance spectrometry and nonradioactive Cu-PTSM. In the brain, only the mitochondrial fraction showed the ability to reduce Cu-PTSM, and the other subcellular fractions did not. In contrast, the cytosolic fraction of Ehrlich ascites tumor cells was the specific site of Cu-PTSM reduction. It was therefore considered that the retention of Cu-PTSM in the brain is closely related to mitochondrial reduction, most probably involving the mitochondrial electron transport system.  相似文献   
7.
Late Effects of Childhood Acute Leukemia and Its Treatment   总被引:1,自引:0,他引:1  
Late effects of childhood acute leukemia and its treatment were studied in 766 patients (684 ALL, 73 ANLL, and 9 others) in Japan who had remained in remission for more than 1 year after their first complete remission. Delayed adverse sequelae involve a wide variety of organs and their functions. Short stature was present in 2.61%, obesity in 3.79%, abnormalities of growth hormone secretion in 1.5%, delayed secondary sex characteristics in 1.5% of males and 0.6% of females, motor disturbances in 1.17%, sensory disturbances in 0.91%, intellectual and learning disabilities in 2.48%, abnormal findings in routine neurologic examinations in 1.31%, EEG abnormalities in 4.30%, brain CT abnormalities in 5.09% and cardiac dysfunction in 1.07%. Various other disorders were seen in 20 patients. Many of these delayed adverse sequelae are caused by or related to central nervous system prophylaxis and systemic combination chemotherapy. The results suggest that it is needed to improve therapeutic methods through the stratification of patients by risk factors and detailed analysis of prognostic factors. Moreover it is important to render medical and psychosocial support to long-term survivors of childhood leukemia through interactions between the patient, parents and medical staff.  相似文献   
8.
The cardiac myosin light chain I (LCI) is one of the cardiac muscle structural proteins. A sensitive immunoradiometric assay kit for LCI by using LCI monoclonal antibodies is developed. We estimated LCI in the patients with Duchenne muscular dystrophy (DMD) and Kugelberg-Welander disease (KW). The results suggested that LCI has close relationships with the functional disturbances of skeletal muscles, especially disturbances of pulmonary ventilation. Therefore we studied properties and localizations of LCI in the skeletal muscles by Western blotting and immunohistochemical methods. In Western blotting method LCI monoclonal antibodies have a band of 27 KD proteins of skeletal muscles. LCI has also found to be localized in type 1 fibers in frozen sections of biopsied of human skeletal muscles. LCI was measured from 47 patients with DMD and 8 patients with KW. The average serum LCI levels in the patients with DMD were 11.79 ng/dl and its levels in the patients with KW were in the normal range (under 2.5 ng/dl). Among 12 patients receiving negative pressure chest respirator, the levels of LCI were also under 2.5 ng/dl. Serum LCI decreased with increasing age and reduced physical activity. The levels of LCI has obvious positive correlations with CK and myoglobin. These results suggested that the measurements of serum LCI are useful as one of the markers of disease severity and the determination of suitable time of using respirator.  相似文献   
9.
To determine the clinical recommended dosage regimen of risedronate for the treatment of involutional osteoporosis in Japanese patients, dose-response relationships for the efficacy and safety of this drug were investigated using a multi-center, randomized, double-blind, parallel group comparative design with four dose levels of risedronate (placebo, 1 mg, 2.5 mg and 5 mg per day). A total of 211 patients diagnosed with involutional osteoporosis according to the criteria proposed by the Japanese Society for Bone and Mineral Research were randomized and received one of the four doses once daily for 36 weeks. All patients were supplemented with 200 mg of calcium daily in the form of calcium lactate. The primary efficacy endpoint was the percent change in bone mineral density of the lumbar spine (L2-L4 BMD) determined by dual-energy X-ray absorptiometry (DXA) from baseline to the time of final evaluation. Changes in biochemical markers of bone turnover and safety profile were also compared. Percent changes in L2-L4 BMD at final evaluation in the placebo, and 1-, 2.5-, and 5-mg risedronate groups were 0.79+/-5.30, 2.71+/-4.93, 5.29+/-3.96, and 5.15+/-4.25% (mean+/-SD), respectively. A linear dose-response relationship was obtained up to a dose of 2.5 mg, whereas no further increase in BMD was observed at 5 mg. The decrease in bone turnover markers, including N-terminal osteocalcin, phosphorus, and urinary deoxypyridinoline, also showed a linear dose-response relationship up to a dose of 2.5 mg. Alkaline phosphatase level decreased linearly up to a dose of 5 mg. Risedronate was well tolerated in this 36-week study with 1- to 5-mg doses. Neither the overall incidence of adverse events nor the percentage of patients without problem in overall safety assessment differed significantly among the dose groups including the placebo group. Based on these results, a once-daily dose of 2.5 mg of risedronate, which is half that used in Caucasians, is recommended for the treatment of involutional osteoporosis in Japanese patients.  相似文献   
10.
Surgical treatment for the recurrence of colorectal cancer   总被引:2,自引:0,他引:2  
We report the results of a retrospective study conducted on patients who developed recurrence following surgery for colorectal cancer, and present a practical plan to improve the survival rates. Of 974 patients who underwent surgery for colorectal cancer in our hospital during the 20 years between 1974 and 1993, 152 developed recurrence, as local recurrence in 70 (7.2%), as liver metastasis in 47 (4.8%), and as pulmonary metastasis in 35 (3.6%). The number of patients who underwent reoperation or curative resection was 54 (77.1%) and 13 (24.1%), respectively, of those with local recurrence, 16 (34.0%) and 6 (37.5%) of those with liver metastasis, and 6 (17.1%) and 6 (100.0%) of those with pulmonary metastasis. The 3- and 5-year survival rates were 13.4% and 8.9%, respectively, after reoperation for local recurrence, 14.4% and 0%, after reoperation for liver metastasis, and 53.3% and 53.3% after reoperation for pulmonary metastasis. Although evaluation was difficult owing to the small number of patients with lung metastasis, resection of a pulmonary lesion resulted in a good outcome. Furthermore, a significant difference in 3- and 5-year survival rates was observed between patients who underwent reoperation and those who underwent conservative treatment, for whom the survival rates were 0% and 0% following local recurrence, 4.6% and 0% following liver metastasis, and 0% and 0% following lung metastasis, at 3 and 5 years, respectively. These findings indicate that aggressive surgery for recurrence may result in a better outcome.  相似文献   
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