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61.
In two previous studies, we observed that recombinant human interleukin- 3 (IL-3) induced an increase in marrow burst-forming unit-erythroid- derived colonies in vitro in some patients with Diamond-Blackfan anemia (DBA). To determine whether a similar erythropoietic response could be induced in vivo, we treated 13 patients with DBA (aged 4 to 19 years) with two preparations of IL-3. All patients had absent absolute reticulocyte counts and markedly reduced to absent recognizable bone marrow erythroid elements; patients with circulating reticulocytes in the previous 12 months were excluded from study. All patients except 1 had failed steroid therapy and had been transfusion-dependent since infancy; 1 patient was maintained on high-dose prednisone at the time of enrollment. On the first arm of the study, IL-3 (Immunex Corp, Seattle, WA) was administered subcutaneously using a dose escalation regimen of 125 to 500 micrograms/m2/day in divided dosage at 12-hour intervals, coadministered with 1.5 mg/kg/d of oral ferrous sulphate. Of the 13 patients that entered the trial, 4 stopped prematurely because of adverse side effects. In the other 9 evaluable cases, reticulocytes increased transiently in 1 patient from 0 to 65 x 10(9)/L after 35 days of IL-3 therapy at 250 micrograms/m2, but transfusion dependency persisted. One transient peak in absolute reticulocyte count was noted in 6 other patients, but no erythroid response was observed after completion of a full course of IL-3. Oral prednisone at 0.5 mg/kg/d was then coadministered with IL-3 at 500 micrograms/m2 to 5 of the patients without effect, and treatment was stopped. In 2 patients, a second preparation of IL-3 (Sandoz Canada Inc, Dorval, Quebec, Canada) was initiated in a dose escalation regimen of 2.5 to 10 micrograms/kg and was coadministered with ferrous sulphate. No erythroid response was observed in either patient, and in one of the two, alternate-day subcutaneous recombinant erythropoietin at 300 U/kg was administered for 3 weeks in combination with daily IL-3 at 10 micrograms/kg, but no increased erythropoiesis was seen. Significant increases in white blood cell and eosinophil counts during administration of both preparations of IL-3 were observed in all patients. These data show that the response of DBA patients to IL-3 in vivo is heterogeneous and cannot be predicted from in vitro studies. The absence of a corrective effect of IL-3 in these patients with DBA indicates that a deficiency of the cytokine is not central in the pathogenesis of the disorder.  相似文献   
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AIM: The aim of this study was to determine the safety and the efficacy of a gemcitabine/oxaliplatin combination (GEMOX) as first line therapy in patients with metastatic or unresectable locally-advanced pancreatic cancer. PATIENTS AND METHODS: Patients received gemcitabine 1000 mg/m2 as a 10-mg/m2/min infusion on day 1 followed on day 2 by oxaliplatin 100 mg/m2 as a 2-hour infusion, each cycle being given every 2 weeks. All patients had measurable disease and histological diagnosis before inclusion. Patients were treated until progression or for 12 cycles in the absence of progression. Tumor lesions were assessed by computed tomography scan every 4 cycles. RESULTS: Between January 2001 and January 2003, 32 patients were eligible for the study. The objective response rate (OR) was 28.1% with a 12.5% complete response rate (CR). Median progression-free survival and median overall survival were 7 and 9 months, respectively. Median overall survival for patients with metastatic disease and locally-advanced disease were 7 and 25 months, respectively (P < 0.0007). Eleven patients were alive at 1 year (34.4%), six at 2 years (18.8%) and two at 3 years (6%). Fourteen (43.8%) of 32 patients experienced a clinical benefit response. CONCLUSION: These results support the safety, the antitumor activity and the possibility of durable responses of the GEMOX regimen in patients with locally-advanced disease.  相似文献   
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ObjectiveSerum lipoprotein is the most important predictor for microvascular diseases, and may be influenced by rapid urbanization. Currently available data are limited, particularly regarding age-specific lipoprotein status in urban Bangladeshi populations.MethodsBlood lipoprotein levels of 51,353 male and female individuals primarily residing in urban Bangladesh were analyzed. De-identified data (collected between January 2005 and December 2011) were extracted from the Clinical Biochemistry Laboratory Data Archive of International Centre for Diarrheal Disease Research, Bangladesh (icddr,b). For analyses, six age categories were created: (i) <20 years, n = 481; (ii) 20–29 years, n = 1602; (iii) 30–39 years, n = 7272; (iv) 40–49 years, n = 13,582; (v) 50–59 years, n = 15,890; and (vi) 60 years and more, n = 12,526.ResultsMean serum levels of TC, LDL, TG, LDL:HDL and TC:HDL were significantly higher among adults 30–39 years old compared to other age groups, regardless of sex. The proportion of high TC and LDL from 2005 to 2011 among individuals aged 30–39 years old varied widely (p < 0.01 for trend and all pairwise tests).Conclusion30–39 years old individuals had higher concentration of lipoprotein, which increases microvascular disease risk. Further population-based studies are needed to validate our observations in rural areas of Bangladesh.  相似文献   
69.
Following infection with Epstein-Barr virus (EBV), the virus is carried for life in the memory B-cell compartment in a silent state (latency I/0). These cells do not resemble the proliferating lymphoblastoid cells (LCLs) (latency III) that are generated after infection. It is of fundamental significance to identify how the different EBV expression patterns are established in the latently infected cell. In view of the prompt activatability of CD4(+) T cells in primary EBV infection, and their role in B-cell differentiation, we studied the involvement of CD4(+) T cells in the regulation of EBV latency. Lymphoblastoid cell lines (LCLs) were cocultured with autologous or allogeneic CD4(+) T cells. Activated T cells influenced the expression of two key viral proteins that determine the fate of the infected B cell. EBNA2 was down-regulated, whereas LMP1 was unregulated and the cells proliferated less. This was paralleled by the down-regulation of the latency III promoter (Cp). Experiments performed in the transwell system showed that this change does not require cell contact, but it is mediated by soluble factors. Neutralizing experiments proved that the up-regulation of LMP1 is, to some extent, mediated by IL21, but this cytokine was not responsible for EBNA2 down-regulation. This effect was partly mediated by soluble CD40L. We detected similar regulatory functions of T cells in in vitro-infected lymphocyte populations. In conclusion, our results revealed an additional mechanism by which CD4(+) T cells can control the EBV-induced B-cell proliferation.  相似文献   
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During pregnancy, there are important changes in hormone levels such as the huge production of human chorionic gonadotropin (hCG), which is supposed to influence the immune system. The aim of this study was to investigate the effect of hCG on immune response against Leishmania, through the evaluation of the functions of human macrophages infected with L. tropica. This study demonstrated that hCG significantly increased the NO production by rHu‐IFNγ‐primed macrophages then infected with L. tropica, which was correlated with decrease in the number of infected macrophages as well as the number of amastigotes per macrophage in a dose‐dependent manner; however, the greatest effect was shown with the 250 U/mL concentration. The addition of the same concentration of hCG to rHu‐IFNγ‐primed macrophages caused also a major increase in both IL‐6 and IL‐12p40 production. In conclusion, hCG enhances different macrophage functions involved in immunity against L. tropica.  相似文献   
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