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1.
By flow cytometric analysis, we identified the subclass of lymphocytes that proliferates in response to islet-activating protein (IAP), both in vitro (human peripheral blood mononuclear cells, MNC, cultured with IAP) and in vivo (peripheral blood MNC derived from A/J mice treated with IAP). IAP caused a preferential proliferation of CD8+ T cells. These cells expressed the IL-2 receptors on their surface. CD4+ CD8+ T cells could also be detected in these cultures, IAP caused human MNC to produce IL-1 and to induce expression of HLA-DR antigen. These effects may play an important role in the T-cell proliferation induced by IAP, although IAP by itself suppressed the proliferative action of IL-1 in mouse thymocytes. IAP induced proliferation of the purified CD4+ cells but had a smaller effect on the purified CD8+ cells. This suggests that the proliferation of CD8+ cells in IAP-treated MNC depends on the function of other types of cell, e.g. CD4+ cell and macrophage.  相似文献   
2.
The aim of this study was to investigate whether the metabolic syndrome (MS) was associated with an elevated level of C-reactive protein (CRP) and increased arterial stiffness, and to clarify whether combined MS and CRP data had a stronger relation to arterial stiffness than did MS data alone. Brachial-ankle pulse wave velocity (baPWV), CRP, and conventional risk factors were evaluated in 3,412 men and 854 women. Adjusted mean values of baPWV in men with 0, 1, 2, and > or = 3 components were 1,309, 1,372, 1,422, and 1,462 cm/s, respectively (p for trend <0.001). Adjusted mean values of baPWV in women with 0, 1, 2, and > or =3 components were 1,212, 1,292, 1,357, and 1,391 cm/s, respectively (p for trend <0.001). Adjusted geometric mean concentrations of CRP in men with 0, 1, 2, and > or = 3 components were 0.036, 0.049, 0.059, and 0.076 mg/dI, respectively (p for trend <0.001). Adjusted geometric mean concentrations of CRP in women with 0, 1, 2, and > or = 3 components were 0.023, 0.030, 0.057, and 0.077 mg/dI, respectively (p for trend <0.001). In analyses of adjusted mean values of baPWV according to the number of MS components and according to CRP levels within or without top quartile levels, the p value for the trend was significant (<0.001) in both men and women but, in post hoc analyses, comparing high and low CRP levels in each MS component-number group, no significant difference was found. These results suggest that, for prediction of increased arterial stiffness, combining MS and CRP data has little additive effect compared to the use of MS data alone.  相似文献   
3.
Chemotherapy-induced anemia in patients with primary lung cancer.   总被引:6,自引:0,他引:6  
To elucidate the factors which influence the value of hemoglobin, the nadir value of hemoglobin, frequency of blood transfusion and prognostic value of blood transfusion in patients with primary lung cancer during intensive chemotherapy, the hematological features of 124 patients entered into a randomized phase III study containing cisplatin were retrospectively analyzed. There was no difference in the percent nadir hemoglobin value of the first course of chemotherapy (% of pretreatment value) in any of the subgroups with respect to sex, body weight loss, performance status, age, stage, number of metastatic sites or treatment arms. The only predictive indicator for the nadir hemoglobin value in the first course of chemotherapy was the pretreatment value of hemoglobin. The equation for the regression line was y = 1.07 + 0.73x (R2 = 0.663, p < 0.001). The lowest nadir hemoglobin value (% of pretreatment value) during all chemotherapy courses was significantly lower in the subgroups older than 60 years and those with body weight loss. There was an inverse correlation between the accumulated dose of cisplatin and the lowest nadir hemoglobin value (p < 0.05). The frequency of blood transfusion in patients with more than two metastatic sites was significantly higher than in those with one or no metastatic sites (p < 0.05). Survival of patients who had required blood transfusion after chemotherapy was significantly shorter than that of patients who had not (p < 0.05).  相似文献   
4.
The primary objectives of this study were to determine the maximum tolerated dose (MTD) of paclitaxel administered by 3-h infusion to patients with solid tumors, and to characterize the pharmacokinetics of a 3-h infusion in comparison with those of a 24-h infusion. Twenty-seven patients each received one of six levels of paclitaxel, 105, 135, 180, 210, 240 and 270 mg/m2, with premedication. Two patients given 240 mg/m2 and one patient given 270 mg/m2 unexpectedly had grade 3/4 hypotension just after finishing the paclitaxel infusion. Peripheral neuropathy was also dose-limiting at 270 mg/m2. Although granulocytopenia was significantly less severe than with a 24-h infusion, more than half of the patients experienced grade 4 toxicity at doses of 240 or 270 mg/m2. Severe hypersensitivity reactions (HSRs) were not observed. Pharmacokinetic studies using high performance liquid chromatography demonstrated proportionally greater increases in the peak plasma concentration and area under the curve, and decreases in clearance and volume of distribution with increasing dose, suggesting non-linear pharmacokinetics of paclitaxel when given by 3-h infusion. The MTD of paclitaxel given as a 3-h infusion was determined to be 240 mg/m2 with dose-limiting toxicities of granulocytopenia, peripheral neuropathy and hypotension. Hypotension just after infusion, induced by 3-h infusion of paclitaxel, is a new observation which has not been reported previously. The recommended dose for phase II study is 210 mg/m2. Although hypotension was observed as an unexpected toxic effect, paclitaxel could be administered safely over 3 h with premedication and proper monitoring, resulting in reduced myelotoxicity and with no increase in the incidence of HSRs as compared with a 24-h infusion.  相似文献   
5.
The increase in life-span (ILS) of tumor-bearing mice caused by recombinant interleukin-2 (RIL-2) was studied in the solid tumor adenocarcinoma 755 system. With long-term treatment (Days 5-12), RIL-2 (10(5) U/mouse) showed a weak effect (24% ILS), but short-term RIL-2 treatment (Days 5-8 or 9-12) had hardly any effect. Mitomycin, at 2 mg/kg (maximum nontoxic dose), caused 35% ILS with Days 5-8 treatment and only 12% ILS with Days 9-12 treatment. Sequential treatment with mitomycin (Days 5-8) and RIL-2 (Days 9-12) markedly enhanced antitumor activity (88% ILS). This value is significantly greater than that of mitomycin alone or RIL-2 alone (P less than 0.01). Furthermore, mitomycin followed by RIL-2 markedly augmented killing activity of spleen cells that are cytotoxic in vitro. These results indicate that RIL-2 markedly affects the inhibition of growth of a tumor treated with an antitumor agent.  相似文献   
6.
Mitomycin C (MMC) at a dose of 8 mg/m2 was administered by short intravenous infusion to 14 cancer patients. All patients had normal renal, hepatic, cardiac and bone marrow functions. The plasma level of MMC, which was determined by high-performance liquid chromatography over a 24–h period after the infusion, fitted the 2-compartment model curve except for one patient. There was a significant correlation between the area under the time versus concentration curve (AUC) of MMC and the age of patients ( r = 0.558, P < 0.05). Pharmacokinetic parameters in one of the older (a 69-year-old male) patients were extremely different from those of the other 13 patients. This patient experienced severe myelosuppression, probably due to the markedly increased AUC of MMC. Our results suggest that a patient's age has a significant influence on the pharmacokinetics of MMC in patients with normal major organ functions and that in some patients, MMC pharmacokinetics may be altered, possibly due to interpatient variation in the activation or metabolic pathway of MMC.  相似文献   
7.
Summary.  Three non-sense mutants of varicella-zoster virus (VZV) thymidine kinase (TK) gene, VZTK325, VZTK278 and VZTK224, were isolated. The mutants had a single nucleotide substitution at codons 326, 279 and 225, which changed the codon of TGG (tryptophan) to the stop codon TGA. The wild type (WT) and mutant TKs were expressed in E. coli cells and their characteristics were evaluated. VZTK224 lost TK activity, but VZTK325 and VZTK278 maintained 74.8% and 21.2% of the WT TK activity. On the other hand, all mutants lost the thymidylate kinase activity. Moreover, VZTK325 and VZTK278 polypeptides were heat-labile. These data suggest that the carboxy-terminal portion of herpesvirus TK plays an important role in the stable folding of TK and thymidylate kinase activity. Received April 21, 1997 Accepted June 16, 1997  相似文献   
8.
Between April 1985 and May 1988, we conducted a randomized study comparing two standard chemotherapy regimens with the same regimens given on an alternating basis in patients with small-cell lung cancer. The patients were randomly assigned to receive cyclophosphamide at a dose of 800 mg/m2 intravenously (IV) on day 1, doxorubicin at 50 mg/m2 IV on day 1, and vincristine at 1.4 mg/m2 IV on day 1 (CAV); cisplatin at 80 mg/m2 IV on day 1 and etoposide at 100 mg/m2 IV on days 1, 3, and 5 (PE); or CAV alternating with PE (CAV/PE). Each regimen was repeated every 3-4 weeks. Three hundred patients were entered in the study, and 288 of them were eligible for analysis (97 for CAV, 97 for PE, and 94 for CAV/PE). The response rates for PE (78%) and CAV/PE (76%) were significantly higher than the rate for CAV (55%), while the complete response rates were similar (14%, 16%, and 15%, respectively). Nine (23%) of 39 patients who failed to respond to the initial CAV regimen responded to PE when they were crossed over. In contrast, only one (8%) of 13 patients responded to CAV after failing to respond to the PE regimen, suggesting that these two regimens were partially non-cross-resistant. The response duration on CAV/PE was significantly longer than that with CAV (P = .004). The survival time with CAV/PE (11.8 months) was superior to that with CAV (9.9 months) (P = .027) or that with PE (9.9 months) (P = .056). In patients with limited disease, the survival in the alternating arm was significantly superior to the survival in the CAV arm (P = .014) or the survival in the PE arm (P = .023). The toxic effects were acceptable in all three chemotherapy regimens. These results favor the alternating chemotherapy over either standard chemotherapy, such as CAV and PE, although the differences are not dramatic.  相似文献   
9.
10.
A HeLa cell line continuously expressing recombinant nucleoprotein (rNP) of the Crimean-Congo hemorrhagic fever virus (CCHFV) was established by transfection with an expression vector containing the cDNA of CCHFV NP (pKS336-CCHFV-NP). These cells were used as antigens for indirect immunofluorescence (IF) to detect immunoglobulin G antibodies to CCHFV. The sensitivity and specificity of this IF technique were examined by using serum samples and were compared to those of the IF technique using CCHFV-infected Vero E6 cells (authentic antigen). Staining of the CCHFV rNP expressed in HeLa cells showed a unique granular pattern similar to that of CCHFV-infected Vero E6 cells. Positive staining could easily be distinguished from a negative result. All 13 serum samples determined to be positive by using the authentic antigen were also determined to be positive by using CCHFV rNP-expressing HeLa cells (recombinant antigen). The 108 serum samples determined to be negative by using the authentic antigen were also determined to be negative by using the recombinant antigen. Thus, both the sensitivity and the specificity of this IF technique were 100% compared to the IF with authentic antigen. The novel IF technique using CCHFV rNP-expressing HeLa cells can be used not only for diagnosis of CCHF but also for epidemiological studies on CCHFV infections.  相似文献   
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