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131.
Basophil chemotactic activity (BCA) of eight recombinant human (rh) cytokines was examined. Highly purified basophils were obtained by Percoll discontinuous gradients, followed by negative selection using flow cytometry. Then BCA was measured by means of modified Boyden chamber method. Both interleukin (IL)-3 and granulocyte-macrophage colony-stimulating factor (GM-CSF) had much more potent BCA than complement C5a, leukotriene B4 and platelet activating factor, well known as granulocyte chemotactic factors. Chemotaxis rather than chemokinesis was shown in chequerboard analysis of basophil migration induced by IL-3 and GM-CSF. Relatively high concentrations of IL-5 also induced basophil migration, although predominantly chemokinetic. IL-8 had apparent BCA, which was not so high as that of C5a. In contrast, IL-2, IL-4, interferon(IFN)-gamma and granulocyte colony-stimulating factor (G-CSF) had no significant BCA. These findings suggest that IL-3, IL-5, GM-CSF and, perhaps, IL-8 have an effect on basophil migration as well as modulation of basophil mediator release and may provide some insight into the basophil accumulation observed in late-phase allergic responses.  相似文献   
132.
Basophils were purified from peripheral blood of normal donors using Percoll discontinuous gradients and negative selection by flow cytometry. The mean purity of basophils obtained was 84.7 +/- 4.1 (s.d.)% (range 77.3-90.0%, n = 13). The overall yield of these procedures was 16.0 +/- 2.6% (range 11.0-19.9%, n = 13), and cell viability of purified basophils exceeded 90%. Properties of highly purified basophils obtained by flow cytometry did not differ from those of partially enriched basophil preparations from Percoll discontinuous gradients in respect of: (i) intracellular histamine content; (ii) percentage of spontaneous histamine release in buffer; and (iii) percentage of histamine release triggered by ionophore A 23187 or anti-IgE. Moreover, purified basophils responded chemotactically to complement C5a in a dose-dependent manner. These findings suggest that our procedure for purification of human basophils does not affect the functions of basophils and may be useful for in vitro studies on the role of basophils in hypersensitivity reactions such as bronchial asthma.  相似文献   
133.
Musa basjoo (MB) is a species of the banana plant belonging to the genus Musa that has been used as a folk medicine. However, evidence-based biological activities and the molecular mechanism of action of MB are unknown. Thus, the aim of the present study was to examine whether the crude dried leaf extracts of MB inhibit the growth of colorectal (HT29 and HCT116) and other types (HepG2, MCF-7 and PC-3) of human cancer cell lines. Crude extracts of MB inhibited the growth of cells with IC50 values of 136 µg/ml (acetone extract, HT29), 51 µg/ml (acetone extract, HCT116), 45 µg/ml (acetone extract, HepG2), 40 µg/ml (acetone extract, MCF-7), 29 µg/ml (acetone extract, PC-3), 175 µg/ml (methanol extract, HT29), 137 µg/ml (methanol extract, HCT116), 102 µg/ml (methanol extract, HepG2), 85 µg/ml (methanol extract, MCF-7), and 85 µg/ml (methanol extract, PC-3) in colony formation assays, and 126 µg/ml (acetone extract, HT29), 68 µg/ml (acetone extract, HCT116), 260 µg/ml (methanol extract, HT29), and 216 µg/ml (methanol extract, HCT116) in MTT assays. Thin layer chromatography analysis revealed the potential existence of aromatic compounds in the acetone extract of MB. Flow cytometric analysis indicated that the percentage of cells in G1 increased, and this was associated with a concomitant decrease of cells in the S and/or G2-M phases of the cell cycle. When colorectal cancer cells were treated with acetone extract of MB, there was a marked decrease in the levels of expression of the cyclin D1, cyclin E, cdk2 and cdk4 proteins and a marked increase in the levels of the expression of the p21CIP1, p27KIP1, and p53 proteins, but those of apoptosis-associated protein PARP did not change. There was a tendency for acetone extract of MB to inhibit xenograft tumor growth in mice. Collectively, the crude extracts of MB contain active components that exert growth inhibition of human cancer cells. This is the first systematic study of the anticancer activity of MB and may broaden insights into the possible clinical approach of specific herbal medicines.  相似文献   
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Objective. Early diagnosis of Takayasu arteritis in the acute stage (prepulseless stage) is extremely difficult. Identification of a useful approach to detecting the initial changes of arteritis is therefore desirable. Methods. Careful clinical examination of a young woman with persistent fever and dry cough revealed faintly audible bruits at the cervical, supraclavicular, and abdominal regions. Aortographic features suggested thickening of the wall of the descending thoracic aorta. Magnetic resonance imaging (MRI) of this area was diagnostic. Results. MRI demonstrated involvement of the ascending aorta and right main pulmonary artery. Steroid therapy (prednisolone 60 mg/day) induced dramatic clinical and radiologic improvement in 2 months. Conclusion. This is the first report of MRI-documented reduction in the thickness of the walls of both the aorta and the pulmonary artery following steroid therapy.  相似文献   
137.
BACKGROUND: To diagnose left main trunk (LMT) infarction by 12-lead standard electrocardiogram (ECG) is an important emergency technique, but the features in LMT infarctions have not been clarified. METHODS AND RESULTS: The study enrolled 140 subjects who were divided into 4 groups according to the location of the culprit artery: 35 with LMT, 35 with left anterior descending artery (LAD), 35 with right coronary artery and 35 with left circumflex artery. Various parameters obtained from the ECGs were analyzed. Average QTc interval (0.51 +/- 0.06 s) in LMT group was markedly longer than that in the 3 other groups. Average QRS axis (-10 +/- 77 degrees) in LMT infarction showed a remarkable left deviation. ST-segment elevation in lead aVR occurred in 28 patients (80.0%) in the LMT group. The ECG features of the LMT group could be classified into 2 main groups: right bundle branch block (RBBB) with a marked left axis deviation (RBBB + LADEV type) and ST-segment elevation in leads V2-5, I and aVL without abnormal axis deviation (LAD type). CONCLUSION: Either ST-segment elevation in lead aVR and marked prolongation of both the QRS width and QTc interval with a prominent abnormal axis deviation or ST-segment elevation in the broad anterior precordial lead with a normal QRS axis strongly suggests LMT infarction.  相似文献   
138.
Limited data exists on ST-segment elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI) managed by a well-organized cardiac care network in a metropolitan area. We analyzed the Tokyo CCU network database in 2009–2010. Of 4329 acute myocardial infarction (AMI) patients including STEMI (n = 3202) and NSTEMI (n = 1127), percutaneous coronary intervention (PCI) was performed in 88.8 % of STEMI and 70.4 % of NSTEMI patients. Mean onset-to-door and door-to-balloon times in STEMI patients were shorter than those in NSTEMI patients (167 vs 233 and 60 vs 145 min, respectively, p < 0.001). Coronary artery bypass graft surgery was performed in 4.2 % of STEMI and 11.4 % of NSTEMI patients. In-hospital mortality was significantly higher in STEMI patients than NSTEMI patients (7.7 vs 5.1 %, p < 0.007). Independent correlates of in-hospital mortality were advanced age, low blood pressure, and high Killip classification, statin-treated dyslipidemia and PCI within 24 h were favorable predictors for STEMI. High Killip classification, high heart rate, and hemodialysis were significant predictors of in-hospital mortality, whereas statin-treated dyslipidemia was the only favorable predictor for NSTEMI. In conclusion, patients with MI received PCI frequently (83.5 %) and promptly (door-to-balloon time; 66 min), and had favorable in-hospital prognosis (in-hospital mortality; 7.0 %). In addition to traditional predictors of in-hospital death, statin-treated dyslipidemia was a favorable predictor of in-hospital mortality for STEMI and NSTEMI patients, whereas hemodialysis was the strongest predictor for NSTEMI patients.  相似文献   
139.
Recently, it was reported that remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome could be complicated with solid tumors. In a retrospective, multicenter study between October, 2003 and September, 2010, we investigated the characteristics of patients with paraneoplastic RS3PE syndrome who fulfilled following criteria: (1) bilateral pitting edema of hands or feet or both, (2) sudden onset of polyarthritis, and (3) age >50?years, (4) seronegativity for rheumatoid factor (RF). A total of 33 cases fulfilled the above criteria. Eight patients (seven men and one woman) developed cancer within 2?years of RS3PE syndrome onset. There was no significant difference between the neoplastic and nonneoplastic groups in the proportions of patients with fever, symmetrical polyarthritis, pitting edema, and good response to corticosteroids. Serum matrix metalloproteinase 3 (MMP-3) level (median 437.3?ng/ml) in the paraneoplastic RS3PE patients was significantly higher than that in patients without neoplasia (median 114.7?ng/ml) (p?相似文献   
140.
Chronic renal failure is one of the risk factors for carotid atherosclerosis. We report two cases of stenosis of the carotid bifurcation treated by carotid endarterectomy. A 66-year-old man with a 17-year history of hemodialysis experienced repeated episodes of right hemiparesis. Cerebral angiography showed severe stenosis of the cervical carotid bifurcation bilaterally. Left and right carotid endarterectomy operations were performed one month apart. The postoperative course was uneventful, and the patient returned home without neurological symptoms. The second case was in a 49-year-old woman with a 15-year history of hemodialysis had vertigo of one month duration. Cerebral angiography revealed occlusion of the left subclavian artery, and the distal left axillary artery was filled by retrograde flow from the left vertebral artery. Stenosis of the right carotid bifurcation was also noted. Right carotid endarterectomy was performed without any complications. Although a high incidence of intraoperative complications and of recurrent stroke after carotid endarterectomy (CEA) has been reported in chronic renal failure patients, the poor prognosis of the natural history of severe carotid stenosis in chronic renal failure should be taken into consideration. The cases reported indicate that carotid endarterectomy is safe and justified for carotid stenosis in chronic renal failure patients.  相似文献   
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