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81.
Decker T; Flohr T; Trautmann P; Aman MJ; Holter W; Majdic O; Huber C; Peschel C 《Blood》1995,86(3):1115-1123
We investigated the production of cytokines by highly purified T helper cells from B-cell chronic lymphocytic leukemia (B-CLL) patients stimulated by different activation pathways, and we studied the influence of various accessory cell populations on the pattern of the secretion of cytokines, including interleukin (IL)-2, IL-4, interferon- gamma (IFN-gamma), and IL-10. Neither a qualitative nor a quantitative difference in cytokine production and proliferative capacity was observed in CLL-derived purified T cells compared with normal individuals, when T cells were stimulated by different pathways, including CD3, CD2, and costimulation with CD28. Addition of autologous accessory cells (aAC), however, dramatically influenced the cytokine pattern of normal versus B-CLL-derived T cells. CLL cells as aAC caused a marked increase of IL-2, whereas IFN-gamma was only slightly induced and IL-4 was not influenced. In contrast, in normal individuals addition of aAC, which predominantly consisted of monocytes, resulted in a significant increase of IFN-gamma and a reduction of IL-4 secretion. IL-2 production was inhibited by higher concentrations of aAC. The increased stimulation of IL-2 production by CLL cells was not specific to the leukemic cell population, as purified B cells from normal individuals had the same effect. On the other hand, purified monocytes from CLL patients and controls both induced IFN-gamma production and inhibited IL-4 secretion. After antigen-specific stimulation with tetanus toxoid, cytokine secretion was influenced by the type of aAC in a similar pattern. We conclude that T helper cells derived from patients with B-CLL are intrinsically normal and that the predominance of B cells as accessory cells in CLL significantly alters the immune function of T helper cells in vitro. 相似文献
82.
Phase I study of Topotecan, a new topoisomerase I inhibitor, in patients with refractory or relapsed acute leukemia 总被引:5,自引:1,他引:5
Kantarjian HM; Beran M; Ellis A; Zwelling L; O'Brien S; Cazenave L; Koller C; Rios MB; Plunkett W; Keating MJ 《Blood》1993,81(5):1146-1151
The purpose of this study was to define, in a phase I study in leukemia, the maximally tolerated dose (MTD), major toxicities, and possible antitumor activity of Topotecan, a new topoisomerase I (topo I) inhibitor. Topotecan was delivered by a 5-day continuous infusion every 3 to 4 weeks to patients with refractory or relapsed acute leukemia, at doses ranging from 3.5 mg/m2 to 18 mg/m2 per course. Twenty-seven patients were treated, including 17 patients with acute myelogenous or undifferentiated leukemia, 7 with acute lymphocytic leukemia, and 3 with chronic myelogenous leukemia in blastic phase. Severe mucositis was the dose-limiting toxicity occurring in two of five patients treated with Topotecan 11.8 mg/m2 per course; a third patient had prolonged myelosuppression. At the MTD of 10 mg/m2 per course, 1 of 12 patients had severe mucositis and 5 had mild-to- moderate mucositis. Nausea, vomiting, diarrhea, and prolonged myelosuppression were uncommon. Three patients (11%) achieved a complete response, two (7%) had a partial response, and one (4%) had a hematologic improvement. The overall complete plus partial response rate was 19%, and 24% in acute myelogenous or undifferentiated leukemia. A novel in vitro assay that quantifies Topotecan-stabilized topo I-DNA complexes in patient samples was used, which demonstrated heterogeneity in the ability of Topotecan to interact with topo I, the intracellular target of Topotecan. This phase I study defined the MTD of Topotecan to be 10 mg/m2 by continuous infusion over 5 days every 3 to 4 weeks in patients with refractory or relapsed acute leukemia. Severe mucositis was the dose-limiting toxicity. Future studies will define the precise activity of Topotecan in different leukemia subsets, its efficacy in combination with other antileukemic drugs, and correlations between Topotecan-induced topo I-DNA complex formation and individual patient response to Topotecan. 相似文献
83.
Interferon-alpha stimulates production of interleukin-10 in activated CD4+ T cells and monocytes 总被引:4,自引:1,他引:4
Aman MJ; Tretter T; Eisenbeis I; Bug G; Decker T; Aulitzky WE; Tilg H; Huber C; Peschel C 《Blood》1996,87(11):4731-4736
In the present study, we investigated the effect of interferon-alpha (IFN-alpha) on the expression of interleukin-10 (IL-10) mRNA and protein synthesis in human monocytes and CD4+ T cells. In mononuclear cells, IFN-alpha induced expression of IL-10 mRNA and further enhanced lipopolysaccharide (LPS)-stimulated IL-10 expression. In purified monocytes, a strong expression of IL-10 mRNA induced by LPS was not further enhanced by IFN-alpha. In highly purified CD4+ T cells, IFN- alpha upregulated IL-10 mRNA upon activation with phytohemagglutinin and phorbol myristate acetate. In purified monocytes, an effect of IFN- alpha on IL-10 protein synthesis was dependent on costimulation with LPS. Maximal stimulation of IL-10 protein by IFN-alpha was seen after prolonged incubation periods of 48 to 96 hours, whereas IFN-gamma reduced IL-10 production in the early incubation period. Similar effects of IFN-alpha were observed in CD4+ T cells activated with CD3 and CD28 monoclonal antibodies. Addition of IFN-alpha caused an increase of IL-10 in culture supernatants of activated T-helper cells of more than 100% after 96 hours of incubation. In contrast, other cytokines, including IFN-gamma and IL-4, had no influence on IL-10 secretion stimulated by CD3 and CD28 in CD4+ T cells. In serum samples of IFN-alpha-treated individuals, we failed to detect an influence of cytokine treatment on IL-10 serum levels, confirming the requirement of additional activating signals for IFN-alpha-mediated effects on IL-10 synthesis. In conclusion, IFN-alpha enhances the late induction of IL- 10, which physiologically occurs upon stimulation of monocytes and T cells. Biologically, this effect might enhance the negative-feedback mechanism ascribed to IL-10, which limits inflammatory reactions. 相似文献
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87.
WHO生存质量评估简表的等价性评价 总被引:20,自引:0,他引:20
目的评价WHO生存质量评估简表(WHOQOL-BREF)在13个国家的等价性。方法采用多组验证性因子分析方法,对世界卫生组织生存质量研究小组提供的13个国家的数据进行分析,评价WHOQOL-BREF不同国家的等价性。结果各个国家的各个领域的Cronbachα系数均大于0·7,分布在0·7至0·88之间。除了英国和挪威之外,其它国家的社会关系领域的Cronbachα系数均大于0·65。采用根据世界卫生组织生存质量研究小组研制量表时构建的四因子模型对数据分别进行拟合,拟合优度指数(CFI)均大于0·8,其中德国、西班牙和美国的拟合优度指数大于0·9。多组验证性因子分析发现模型拟合尚可,CFI等于0·88,各个国家的因子负荷不全相等,因子负荷的轮廓相似。结论WHOQOL-BREF在13个国家具有相同的因子结构,且有等价性。 相似文献
88.
目的 与开腹胆囊切除术相比,腹腔镜胆囊切除术(LC)有减少术后不适和较少的创作,但仍有改进的余地。方法:为进一步减轻手术创伤,我们引进了针式腹间胆囊切除术,共29例。结果 平均手术时间为75分钟,19例当天出院,10例隔天出院,其中1例是胆总管探查。结论 针式航空 镜胆囊切除术是一种可靠的技术。 相似文献
89.
B Hitze A Bosy‐Westphal S Plachta‐Danielzik F Bielfeldt M Hermanussen MJ Müller 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(2):256-262
Aim: This study investigates the effect of rapid weight gain in term children, adolescents and young adults born appropriate for gestational age. Methods: In all, 173 girls and 178 boys aged 6.1–19.9 (12.5 ± 3.1)years participated. Rapid weight gain (group 1) was defined as a change in weight‐SDS (standard deviation score) from birth till two years >0.67, ‘no change’ as ≥?0.67 and ≤0.67 (group 2) vs ‘slow weight gain’ as 0.67 (group 3). BMI‐SDS, waist circumference (WC) z‐score, fat mass (FM)/fat free mass (FFM; Air‐Displacement‐Plethysmography), resting energy expenditure (REE; ventilated hood system), cardio‐metabolic risk factors, serum leptin and adiponectin were assessed. >90th age‐/sex‐specific BMI‐percentile was defined as overweight. Parental BMI, socio‐economic status and lifestyle were assessed as confounders. Results: A total of 22.8% gained weight rapidly, and 15.7% was overweight. Group 1 compared with group 2 and 3 subjects was taller, heavier and had a higher prevalence of overweight (girls/boys: 26.2%/28.9% vs 11.6%/19.0% vs 2.8%/5.0%; p < 0.01/p < 0.05). Concomitantly, a higher WC, %FM and FFM were observed. Rapid weight gain was positively associated with REE (adjusted for FFM) in boys (r = 0.26; p < 0.01), but not with cardio‐metabolic risk factors. Conclusion: Rapid weight gain was related to increases in height, weight, a higher prevalence of overweight and central fat distribution. In addition, rapid weight gain was related to a higher REE in boys, but not to cardio‐metabolic risk factors. 相似文献
90.
Locally deranged joint anatomy can predispose to septic arthritis which can be managed by surgical debridement. We present a case of manubriosternal subluxation/dislocation caused by kyphoscoliosis leading to manubriosternal septic arthritis. 相似文献