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991.
992.
A selective inhibitor of Na+/Ca2+ exchanger, SEA0400, preserves cardiac function and high-energy phosphates against ischemia/reperfusion injury 总被引:2,自引:0,他引:2
Feng NC Satoh H Urushida T Katoh H Terada H Watanabe Y Hayashi H 《Journal of cardiovascular pharmacology》2006,47(2):263-270
The Ca2+ overload by Ca2+ influx via Na+/Ca2+ exchanger (NCX) is a critical mechanism in myocardial ischemia/reperfusion injury. We investigated protective effects of a novel selective inhibitor of NCX, SEA0400, on cardiac function and energy metabolism during ischemia and reperfusion. Langendorff-perfused rat hearts were exposed to 35 minutes global ischemia and 40 minutes reperfusion. Using 31P nuclear magnetic resonance spectroscopy, cardiac phosphocreatine (PCr), ATP, and pHi were monitored. SEA0400 did not change the basic cardiac function, but improved the recovery of left ventricular developed pressure (LVDP) after reperfusion (27.6 +/- 4.9 mm Hg in control, 101.2 +/- 19.3 mm Hg in 0.1 microM, and 115.5 +/- 13.3 mm Hg in 1 microM SEA0400, means +/- SE, n = 6, P < 0.05). SEA0400 reduced left ventricular end-diastolic pressure and increased coronary flow after reperfusion. SEA0400 improved the recoveries of cardiac phosphocreatine and ATP after reperfusion, but did not affect pHi. There were significant linear correlations between left ventricular developed pressure and cardiac phosphocreatine (r = 0.79, P < 0.05), and left ventricular developed pressure and ATP (r = 0.80, P < 0.05). However, SEA0400 increased the incidence and duration of reperfusion ventricular arrhythmias. SEA0400 added only after reperfusion also improved both the contractile function and energy metabolism. It is concluded that the selective inhibition of NCX may be effective to preserve high-energy phosphates and to improve cardiac function after reperfusion, but may not be able to prevent fatal arrhythmias. 相似文献
993.
Chikara Ogura Kazuaki Majima Kazuyoshi Nakasawa Ikan Nakamura Yoichi Umezawa Hajime Ueda 《European journal of clinical pharmacology》1978,13(6):413-418
Summary A new method, 24-hour polygraphy (EEG, EMG, and EOG), was applied not only to investigate the influence of hypnotics on night sleep, but to examine the precise influence on sleep-wake-fulness rhythm the day following administration. The hypnotics used were flurazepam 15 mg and nitrazepam 5 mg. The subjects were healthy volunteers, 5 men and 4 women, aged 20–50 years. The polygraphic record was made three times for each subject. Flurazepam prolonged sleep time (%) significantly (p<0.05), shortened sleep latency (p<0.05), decreased waking period (p<0.05), and increased the percentage of Stage 2 sleep (p<0.1) in comparison to nitrazepam. Flurazepam 15 mg appears to be a better hypnotic than nitrazepam 5 mg, but caution is required in its use because of a greater residual sedative effect on the following day. Some nondrug factors affecting sleep and a method for detecting the residual effect of hypnotics are discussed. 相似文献
994.
This report consists of two cases who died after a neurological disorder of the central nervous system consistent with Behcet's disease clinically and pathologically. Post-mortem examination of the central nervous system revealed mild diffuse meningo- encephalitis with multiple foci of softening, demyelination and glial cell accumulation in the pons, midbrain, cerebral peduncle and internal capsule. The significance of these morphological findings has been discussed from an etiological viewpoint of Neuro-Behcet's syndrome. 相似文献
995.
A case of diprosopus, a very rare malformation belonging to dupli-citas, of a female newborn is reported. This diprosopus monauchenos tetrophthalmus triotus dioris was delivered from a 33 years old multipara. Autopsy revealed duplication of cerebral hemispheres, 1st, 2nd and 3rd cranial nerves, hypophysis, intracranial internal carotid arteries, basilar artery and tip of tongue. This diprosopus had also congenital cardiac and great vessel anomalies consisting of double outlet right ventricle without pulmonary stenosis, coarctation of aorta (infantile type), ventricular septal defect, patent ductus arteriosus, patent foramen ovale and thick right ventricular wall. Except for mesenterium commune, the organs in the chest and abdomen, and the extremities were normal in position, shape and number. ACTA PATH. JAP. 20: 239–249, 1970. 相似文献
996.
Hajime Kazamatsuri M.D. Mineko Hattori Ph.D. 《Psychiatry and clinical neurosciences》1979,33(3):319-322
Serum levels of both phenytoin and phenobarbital were determined by homogenous enzyme immunoassay in 59 epileptic patients treated chronically with either Comital-L or Hydantol-F tablets. The majority of the patients receiving Comital-L tablets showed low serum levels of phenytoin and high serum levels of phenobarbital, while patients treated with the usual daily dosage of Hydantol-F tablets showed adequate therapeutic serum levels of both phenytoin and phenobarbital. From the results obtained, the dose ratio of phenobarbital to phenytoin in Comital-L tablet seemed inappropriate to obtain adequate therapeutic serum levels of both drugs simultaneously. Since the dosage of each anticonvulsant drug used concurrently should be established individually, the use of such fixed-dosage mixture tablets of antiepileptic drugs as Comital-L or Hydantol-F in daily clinical practice should be reconsidered from the viewpoint of serum level monitoring of antiepileptic drugs. 相似文献
997.
Yoshida J Kumagai S Tabuchi T Kosaka H Akasaka S Kasai H Oda H 《International archives of occupational and environmental health》2006,79(2):115-122
Objectives: To investigate the effect of dioxin on the formation of oxidative DNA damage and urinary mutagenicity, we measured the concentrations
of serum dioxins and lymphocytic 8-hydroxydeoxyguanosine (8-OH-dG) in 57 male waste incinerator workers, urinary 8-OH-dG and
urinary mutagenicity in 29 male waste incinerator workers. Methods: Information about the subjects was obtained from a questionnaire. Concentrations of polychlorinated dibenzo-p-dioxin (PCDD), polychlorinated dibenzofuran (PCDF), and coplanar-polychlorinated-biphenyl (Co-PCB) in serum samples from
the workers were measured with a high-resolution gas chromatograph /high-resolution mass spectrometer. Lymphocytic and urinary
8-OH-dG levels were measured with a high-performance liquid chromatography-electrochemical detector system. The urinary mutagenicity
was measured with umu assay. Results: The lymphocytic 8-OH-dG level showed a negative association with the serum dioxin level (total value of TEQ-PCDD, PCDF,
and Co-PCB). Urinary 8-OH-dG did not show correlation with serum dioxin level, but showed positive correlation with the smoking
index. Conclusions: With respect to the subjects‘ serum dioxin level, dioxin did not increase the urinary 8-OH-dG level by oxidative DNA damage,
but upregulation of the primary defenses with oxidative damage and/or DNA repair system activity might have occurred. 相似文献
998.
Jia L Takahashi M Yoshioka T Morimoto H Ise H Ikeda U 《Current vascular pharmacology》2006,4(1):59-65
In the past decade, researchers have defined committed stem or progenitor cells from various tissues, including bone marrow, peripheral blood, brain, liver and reproductive organs, in both adult animals and humans. Recently, endothelial progenitor cells (EPCs) were isolated from peripheral blood mononuclear cells and were shown to be incorporated into foci of neovascularization. This finding that circulating EPCs may home into sites of neovascularization and differentiate into mature endothelial cells in situ is consistent with the concept of 'vasculogenesis' and suggests that vasculogenesis and angiogenesis might constitute complementary mechanisms for postnatal neovascularization. Furthermore, experimental and clinical studies on ischemic cardiovascular diseases suggest a therapeutic potential for EPC transplantation. In this review, we summarize the biological features of EPCs and discuss their therapeutic potential for the treatment of cardiovascular diseases. 相似文献
999.
Ochiai T Nishimura K Noguchi H Kitajima M Tsuruoka Y Takahashi Y Tsukada A Watanabe E Nagaoka I Futagawa S 《Journal of surgical oncology》2006,94(1):45-50
BACKGROUND AND OBJECTIVES: Phosphoribosylation of 5-fluorouracil (5-FU) is an essential step which leads to tumor growth inhibition and orotate phosphoribosyl transferase (OPRT) is the main enzyme that involves in this conversion of 5-FU to 5-fluorouridine monophosphate. This retrospective study was aimed to evaluate the correlation between tumor OPRT activity and the clinical outcome in colorectal cancer (CRC) patients treated by oral 5-FU-based adjuvant chemotherapy. METHODS: Surgical specimen was obtained from resectable 124 CRC patients who were subsequently treated by oral 5-FU-based adjuvant chemotherapy. OPRT activity in the extract of tumor tissue was enzymatically determined. The cut-off value of intratumor OPRT activity against disease free survival was determined by maximal chi2 method. The disease free survival and overall survival in each group were calculated using the Kaplan-Meier method. RESULTS: Patients were divided into two groups by determined cut-off value of intratumor OPRT (0.147 nmol/min/mg protein) (high group: n = 102, low group: n = 22). Five-year DFS (P = 0.035) and OS (P = 0.020) were significantly better for high OPRT group. CONCLUSIONS: This study demonstrated that an assay of tumor OPRT contributes to the determination of 5-FU-based adjuvant chemotherapy outcome and application in clinical practice should be included in tumor analysis prior to 5-FU-based adjuvant chemotherapy. 相似文献
1000.
A 54-year-old woman underwent mastectomy and axillary lymph node dissection for infiltrating ductal carcinoma with multiple lymph node involvement. The patient received adriamycin 60 mg/m(2) and cyclophosphamide 600 mg/m(2) (AC) followed by weekly paclitaxel 80 mg/m(2) and external irradiation to the local lymph node regions as adjuvant treatment. After 1 year and 5 months, the patient suffered her first recurrence, developing multiple brain and meningeal metastases. CNS involvement was well controlled by oral capecitabine (2400 mg twice daily, on days 1-21 of a 28-day cycle) and external whole brain irradiation of 50 Gy with minimal toxicity. We suggest that capecitabine contributed to the favorable clinical course in this patient and believe that, as an oral agent, this drug may benefit patients with CNS metastases of breast cancer by allowing home-based therapy. 相似文献