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81.
Yoshio Hayashi Kazuyoshi Ikuta Nobutaka Fujii Kunio Ezawa Shiro Kato 《Archives of virology》1989,105(1-2):129-135
Summary Only one peptide of CD4 (amino acid residues 70–132) among 16 synthetic peptide fragments selectively inhibited HIV-1 replication and HIV-1-induced syncytium formation. Several smaller peptides within this region did not show any activity, except for the peptide (86–132) which showed somewhat lower activity. 相似文献
82.
The prognostic impact of fluctuating levels of C-reactive protein in Brazilian haemodialysis patients: a prospective study. 总被引:5,自引:2,他引:3
Marcelo M Nascimento Roberto Pecoits-Filho A Rashid Qureshi Shirley Y Hayashi Roberto C Manfro Maria A Pachaly Luciana Renner Peter Stenvinkel Bengt Lindholm Miguel C Riella 《Nephrology, dialysis, transplantation》2004,19(11):2803-2809
BACKGROUND: A single elevated C-reactive protein (CRP) value predicts mortality in haemodialysis (HD) patients, but the relative importance of repeated vs occasional positive systemic inflammatory response findings is not known. METHODS: To assess the influence on survival of occasional inflammation, CRP, serum albumin (S-Alb) and fibrinogen were analysed bimonthly in 180 HD patients (54% male, 49+/-14 years). Clinically significant inflammation was defined as CRP >5.1 mg/l, based on the receiver operating characteristics curve for CRP as predictor of death. Based on four consecutive measurements of CRP, patients were assigned into three groups: group 1 (n = 74; 41%), no inflammation (CRP < or = 5.1 mg/l in all measurements); group 2 (n = 65; 36%), occasional inflammation (1-3 measurements of CRP > 5.1 mg/l); and group 3 (n = 41; 23%), persistent inflammation (all measurements of CRP >5.1 mg/l). The nutritional status was evaluated by subjective global assessment (SGA) and body mass index (BMI), and the survival (21 months of follow-up) by Kaplan-Meier curve and Cox model. RESULTS: The median and range of CRP values (mg/l) for group 1, 2 and 3 were: 3.2 (3.2-5.1), 3.6 (3.2-54.9) and 13.8 (5.2-82), respectively (P<0.001), whereas the prevalence of malnutrition, assessed by SGA and BMI, did not differ significantly between the groups. The survival rate by Kaplan-Meier analysis was significantly different among the groups (chi2 = 12.34; P = 0.0004). Patients in group 3 showed the highest mortality (34%; P = 0.001), compared with group 1 (8%) and group 2 (14%; P = 0.01), respectively, whereas there was no significant difference in mortality between groups 1 and 2. Age, CRP, S-Alb level and SGA were independent predictors of mortality. CONCLUSION: The patients with a persistent elevation of CRP had a higher mortality rate than the patients with occasional CRP elevation. Thus, persistent, rather than occasional, inflammation is an important predictor of death in HD patients. 相似文献
83.
Yamaji Yasuyoshi; Nakazato Yuichi; Oshima Naoki; Hayashi Matsuhiko; Saruta Takao 《Nephrology, dialysis, transplantation》2004,19(10):2592-2597
Background. Transferrin binds extracellular iron and protectstissues from iron-induced oxidative stress. The binding of ironand transferrin is pH dependent and conventional peritonealdialysis (PD) solutions have unphysiologically low pH values.Herein, we investigated whether conventional PD solution releasesiron from transferrin and if the released iron causes oxidativestress. Methods. Effects of PD solutions on iron binding to transferrinwere examined with purified human transferrin and transferrinin dialysates drained from PD patients. Oxidative stress inducedby iron released from transferrin was evaluated in terms ofthe formation of thiobarbituric acid reactive substance (TBARS)and protein carbonylation in the human red blood cell (RBC)membrane. The iron deposition in peritoneal tissue from PD patientswas evaluated by Perls' staining with diaminobenzidine intensification. Results. Low pH PD solution released iron from transferrin.This iron release occurred within 1 min. Iron release was notobserved in neutralized PD solution. Iron released from transferrinin low pH PD solution increased TBARS formation and proteincarbonylation in the human RBC membrane. Iron deposition, whichis prominent in the fibrotic area facing the peritoneal cavity,was observed in the peritoneum of PD patients. Conclusions. Iron released from transferrin in low pH PD solutioncan produce oxidative stress in the peritoneum of a PD patient.Neutralizing PD solution can avoid this problem. Iron depositionin the peritoneum may participate in the pathogenesis of peritonealfibrosis in PD patients. 相似文献
84.
Katsushige Tada Ken Nagao Katsuhisa Tanjoh Nariyuki Hayashi 《Circulation journal》2006,70(8):1064-1069
BACKGROUND: Although an elevated blood glucose has prognostic value in cardiovascular disease, few data are available regarding its prognostic value for patients across the spectrum of cardiogenic shock. METHOD AND RESULTS: A total of 81 patients with cardiogenic shock whose blood glucose and adrenaline were measured on arrival at the emergency room (ER) were enrolled in this prospective study. The primary endpoint was death from any cause in hospital. The rate of death was 12.3% (10/81), and the glucose level was lower among patients who were discharged alive than among those who died (8.7+/-3.7 mmol/L vs 13.8+/-6.7 mmol/L, p<0.001). The unadjusted rate of death increased in a stepwise fashion among patients in increasing quartiles of glucose level (p<0.05). The blood glucose level of 9.2 mmol/L had the highest combined sensitivity and specificity for the identification of death. In the multiple logistic-regression analysis for the primary outcome, the adjusted odd ratio for a glucose level of 9.2 mmol/L or more was 5.8 (95% confidence interval, 1.0-32.8, p=0.047). There was a significant positive correlation between the glucose and adrenaline levels (R=0.726, p<0.0001). CONCLUSION: The measurement of blood glucose level on ER arrival provides predictive information for use in risk stratification across the spectrum of cardiac emergencies complicated by cardiogenic shock. 相似文献
85.
Summary We observed a rare cerebrovascular anomaly in a patient with brain-stem infarction. Two right vertebral arteries arose from the subclavian artery and communicated directly with each other under the transverse foramen of the fourth cervical vertebra. The left vertebral artery consisted of a rudimentary artery that arose from the left subclavian artery, ran through the transverse foramen of the sixth cervical vertebra and then tapered down to disappear at the fourth/fifth cervical vertebrae, plus a second, accessory artery that arose from a branch of the left thyrocervical trunk, ran through the transverse foramen of the fifth cervical vertebra and tapered off to disappear at the first/second cervical vertebrae. 相似文献
86.
Cytokine production by peripheral blood monocytes/macrophages in the patients with multiple sclerosis and its suppression by methylprednisolone] 总被引:1,自引:0,他引:1
The production of tumor necrosis factor alpha (TNF alpha), interleukin-1 alpha (IL-1 alpha), interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6) by stimulated peripheral blood monocytes/macrophages (PBM) was assessed in patients with multiple sclerosis (MS), other neurological diseases (OND) or normal controls (NC) using enzyme-linked immunosorbent assay (ELISA). PBM obtained from acute phase of MS produced significantly higher amount of all these cytokines than those from chronic stable MS, OND or NC (TNF alpha, IL-1 alpha, IL-6: p less than 0.01, IL-1 beta: p less than 0.05). Methylprednisolone (MP) inhibited the lipopolysaccharide-induced cytokine production in a dose-dependent manner. These results suggest the possible roles of activated monocytes/macrophages in the acute exacervation of MS and suppressive effect of MP on cytokine production by activated monocytes/macrophages. 相似文献
87.
The proliferative activity of gastric cancer cells with endocrine features was evaluated in five cases by means of a double-immunostaining procedure. The endocrine cells were recognized by a monoclonal antibody to chromogranin A (CGA) and the proliferative activity by a monoclonal antibody to proliferating cell nuclear antigen (PCNA). With the use of two different chromogens it was easy to determine whether CGA was located in the cytoplasm and whether PCNA was located in the nucleus of the same section. The CGA-positive endocrine cells of the normal gastric antral mucosa could be readily distinguished from the PCNA-positive cells scattered in the mucosal neck zones. Over 1,000 CGA-positive cancer cells were counted per case. A few cells (average, less than 1.0%) exhibited faint nuclear staining with anti-PCNA; in no instance was unequivocal PCNA reactivity demonstrable in the gastric cancer cells with endocrine differentiation. By contrast, the PCNA reaction was positive in one fourth to one third of the other cancer cells. These observations suggest that gastric cancer cells with endocrine features are differentiated and do not participate in the cell cycle. 相似文献
88.
T. Terada K. Miyamoto G. Hyotani M. Tsuura Y. Nakamura T. Nishiguchi T. Itakura S. Hayashi N. Komai 《Acta neurochirurgica》1992,118(3-4):108-111
Summary Changes in tumour blood flow under an induced hypertensive state were examined in malignant brain tumours to know if the precondition for the effectiveness of induced hypertensive chemotherapy — relative increase in tumour blood flow — are fulfilled. Tumour blood flow was measured under both a resting and an induced hypertensive state in 12 patients with various malignant brain tumours (6 gliomas, 6 metastatic brain tumours) using xenon-enhanced computed tomography. The blood pressure was elevated 40% above the systemic blood pressure of the resting state by the infusion of angiotensin II. Tumour blood flow increased 30% on average above the normal brain tissue blood flow after the induction of an induced hypertensive state (p < 0.05). The tumour blood flow increased in 11 cases of malignant tumours, but decreased in one case with massive brain oedema after induced hypertension. The increase in blood flow was higher in hypervascular tumours and less in hypovascular tumours. Therefore, induced hypertensive chemotherapy probably will be more effective in hypervascular malignant brain tumours with small mass effects. 相似文献
89.
S Kisara A Hayashi I Maekawa S Furusawa Y Takayanagi K Sasaki 《Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan》1992,112(11):837-845
The biochemical activity of cepharanthine and the possible mechanism by which it reverses the resistance to doxorubicin in P388 leukemia cells were examined in vitro. The microfluorometric analysis of the cellular level of doxorubicin in drug-resistant cells showed that cepharanthine markedly enhanced the sensitivity of doxorubicin against resistant cells in the cellular level. Cepharanthine also enhanced the inhibitory effect of doxorubicin on the incorporation of thymidine into DNA in resistant cells. The analysis of DNA histogram obtained by flow cytometry showed that doxorubicin exerted its growth-inhibitory effect by blocking the cell cycle at the G2 phase in P388 cells. At higher concentrations, doxorubicin prolonged the S phase and inhibited cell cycle progression to the G2/M phase in cells. The treatment with cepharanthine potentiated these blocking effects induced by doxorubicin in cells. It seems that the modifications of the biological effect of doxorubicin by cepharanthine are due to the change of their ability to induce DNA damage in cells. 相似文献
90.
Akihiko Suto Akira Tsuyuki Nobuyoshi Hiraoka Yasuhiro Hosoda Kiyoshi Kikuchi Yasuo Fujishir 《Surgery today》1994,24(10):915-917
A case of cystadenocarcinoma of the appendix with a large cystic lesion is reported. A 49-year-old man undergoing a routine ultrasonic scan was incidentally found to have an abdominal mass measuring some 30 cm in size. The clinical presentation was asymptomatic, and the patient underwent a laparotomy without ascertaining a diagnosis preoperatively. The lesion, which derived from the appendix, was removed and was found to be cystic and contained huge amounts of mucin. The histological findings revealed a well-differentiated cystadenocarcinoma of the appendix, and immunohistochemical staining of the epithelium and mucinous implants in the mass demonstrated a positive reaction for carcinogenic antigens, including carcinoembryonic antigen and carbohydrate antigen. 相似文献