低剂量辐射小鼠骨髓细胞凋亡率的变化

目的:探讨低剂量射线暴露小鼠骨髓细胞凋亡率的变化及意义。方法:以Co60射线照射ICR小鼠,制备不同时间段的骨髓单个核细胞的单细胞悬液,用PI/FITC-Annexin V双染法,通过流式细胞仪检测样品的凋亡率。结果:骨髓单个核细胞早期凋亡率于照射后6 h明显增高;晚期凋亡率随辐射剂量增大而增高。白细胞计数及骨髓细胞微核率于24~30 h与对照组比较差异有显著性(P<0.05,P<0.01)。结论:小鼠骨髓细胞凋亡率的变化可及时反映射线对小鼠骨髓细胞的影响。细胞凋亡率检测可能成为低剂量射线接触人群的早期监控指标。     

血细胞分析仪白细胞计数结果假性增高的原因及处理方法

目的:探讨冷凝集素、血小板聚集、有核红细胞、血球残留对白细胞计数的影响并寻求其解决方法。方法:筛选白细胞结果增高及直方图异常、有报警信号的标本41例,采用不同的方法处理后,用CD-1700型血细胞分析仪复查,并用人工计数法进行计数。结果:冷凝集素、血小板聚集、有核红细胞、血球残留均可致白细胞计数结果假性增高;处理前测定结果与处理后及人工计数法结果比较均有显著性差异(P<0.01),处理后结果与人工法结果基本一致(P>0.05)。结论:应认真分析所得结果和直方图,对结果异常、直方图异常和有报警信号的标本,采用不同的方法处理,或用人工法重新复查后才能发出报告,确保检验结果的可靠性。     

冠心病并2型糖尿病患者超敏C反应蛋白与白细胞水平的变化

目的 探讨高敏C反应蛋白与白细胞水平的变化在不同冠心病患者中的意义.方法 入选我院冠状动脉造影且确诊为冠心病的患者120例,按有无糖尿病分为单纯冠心病组78例,冠心病合并2型糖尿病组42例.抽取晨起空腹肘静脉血,测定白细胞计数(WBC)、总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)及空腹血糖(FPG),采用高敏免疫检测方法检测血浆hs-CRP水平.结果 冠心病并2型糖尿病组hs-CRP、白细胞计数和空腹血糖显著高于单纯冠心病组.结论 hs-CRP、白细胞计数和空腹血糖是冠心病合并2型糖尿病患者的独立危险因素,炎症过程参与了疾病的发生发展.     

Quality control of leucoreduced cellular blood components in France

BACKGROUND AND OBJECTIVES: Since 1 April 1998, all cellular blood components in France have been leucoreduced. The current French standard is < 1 x 10(6) white blood cells (WBC) per unit with a 95% confidence that at least 97% of units will meet this standard. MATERIALS AND METHODS: Quality control (QC) data for leucoreduced cellular blood components were collected from the 41 French blood centres over a 5-month period. Conformance to the standard was determined using a non-parametric approach. RESULTS: More than 98% of the 15 286 red cell concentrates and of the 2895 platelet concentrates tested had < 1 x 10(6) WBC per unit. One filtration device gave unsatisfactory results and its use was discontinued. CONCLUSION: This QC survey shows an overall compliance with the standard. The data illustrate the practical value of identifying devices or centres with consistent QC problems.     

老年2型糖尿病合并血管并发症患者血白细胞和游离脂肪酸的变化

目的研究2型糖尿病(T2DM)和T2DM合并血管并发症患者血白细胞和游离脂肪酸(FFAs)的变化及其相关性，探讨白细胞和游离脂肪酸在T2DM血管并发症发生中的作用．方法用血细胞计数法测定38例T2DM伴血管并发症组、22例T2DM无血管并发症组及20例正常人组的白细胞数，用发色底物法测定三组病人的空腹血清FFAs水平，并将白细胞数与FFAs浓度做相关性分析。结果(1)DM组与正常对照组比较，血白细胞计数、游离脂肪酸水平显著升高(P＜0．05)。(2)T2DM有血管并发症组与无血管并发症组比较，血白细胞计数、游离脂肪酸水平显著升高(P＜0．05)。(3)有并发症组白细胞数与FFAs呈显著正相关(r=0．366，P＜0．05)，FFAs与无并发症组亦呈正相关(r=0．424，P＜0．05)。结论T2DM合并血管并发症患者血白细胞数、FFAs升高，白细胞可与FFAs一样作为非特异性炎症的生物标志物。     

CRP在儿童急性呼吸道感染疾病中的应用

目的探讨C-反应蛋白（CRP）在儿童急性呼吸道感染疾病中的应用价值。方法分别检测432例患儿入院时的和经抗生素治疗72h后的CRP和WBC计数，以80例健康体检儿童为对照。结果细菌感染组CRP和WBC明显升高，与正常对照组比较，t检验差异均有统计学意义（P〈0．05）。病毒感染组与正常对照组比较差异无统计学意义（P〉0．05）。283例CRP阳性的患儿经抗生素治疗72h后，CRP明显下降，与治疗前相比差异有统计学意义（P〈0．05），WBC则轻度下降，与治疗前差异无统计学意义（P〉0．05）。结论CRP能初步鉴别细菌与病毒感染，可指导合理选用抗感染药物并判断疗效。     

Metabolic, hormonal, oxidative, and inflammatory factors in pediatric obesity-related liver disease

OBJECTIVE: To examine the role of metabolic, hormonal, oxidative, and inflammatory factors in pediatric obesity-related liver disease. STUDY DESIGN: In 50 obese children (age 7 to 14 years) with (n = 20, group 1) or without (n = 30, group 2) hypertransaminasemia and ultrasonographic liver brightness, we studied insulin resistance (fasting glucose/insulin ratio [FGIR]) and serum levels of leptin, iron, transferrin, ferritin, C-reactive protein (CRP), white blood cell (WBC) count, tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, C282Y and H63D mutations, and erythrocytic glutathione peroxidase (GPX) activity. RESULTS: FGIR (6.7 +/- 4.1 vs 9.2 +/- 5.2; P = .02), serum ferritin (88.8 +/- 36.0 vs 39.9 +/- 24.0 ng/mL; P = .0001), serum CRP (5.4 +/- 6.0 vs 1.1 +/- 1.6 mg/dL; P = 0.004), and GPX (8.4 +/- 0.9 vs 5.0 +/- 0.5 U/g Hb; P = .05) were significantly higher and more frequently deranged in group 1 than in group 2. FGIR, ferritin, and CRP values were simultaneously deranged in 41% of the group 1 patients and in none of the group 2 patients ( P = .098). Serum leptin, iron, and transferrin, WBC, TNF-alpha, IL-6, and C282Y and H63D mutations were similar in the 2 groups. CONCLUSIONS: Insulin resistance, oxidative stress, and low-grade systemic inflammatory status are implicated in pediatric obesity-related liver disease. These findings may be useful in planning pathophysiologically based therapeutic trials for hepatopathic obese children who are unable to follow hypocaloric diets.     

Reduction in pediatric hospitalizations for varicella-related invasive group A streptococcal infections in the varicella vaccine era

OBJECTIVES: To assess changes in hospitalization rates for invasive group A streptococcal (IGAS) and varicella-associated IGAS (VA-IGAS) infections at a pediatric hospital over a period of 9 years, to characterize clinical features of patients with IGAS infections, and to assess frequency of macrolide-resistant IGAS isolates.Study design Medical records of all hospitalized patients with group A streptococcus isolated from a normally sterile site from 1993 to 2001 were reviewed. Data collected included demographics, clinical course, microbiologic features, outcome, and presence of streptococcal toxic shock syndrome (STSS) or necrotizing fasciitis (NF). Annual hospitalization rates for IGAS were determined. RESULTS: There were 144 patients with IGAS infections, including 11 (8%) with STSS or NF. Overall mortality rate was 2% (3/144) but 18% (2/11) among patients with STSS or NF. Preexisting varicella was present in 16% (23/144); 4 of 23 VA-IGAS cases had STSS or NF. Although there was no change in annual hospitalization rates for IGAS infections during the study period, the percentage of VA-IGAS hospitalizations decreased from 27% in the prevaccine era (1993 to 1995), to 16% during vaccine implementation (1996 to 1998) and 2% during widespread vaccine use (1999 to 2001) (linear-by-linear association, P=.001). Macrolide resistance was low in 1993 to 1995 (5%, 1/19) and 1996 to 1998 (0%, 0/42) among tested IGAS isolates and increased significantly in 1999 to 2001 (13%, 5/38) (Fisher exact, P=.035). CONCLUSIONS: A decline in pediatric varicella-related IGAS hospitalizations was temporally associated with utilization of varicella vaccine. These data reinforce the importance of universal varicella vaccination for children. Increasing macrolide resistance among IGAS isolates indicates a need for continued surveillance.     

Drastic effect of cell density on the cytotoxicity of daunorubicin and cytosine arabinoside

White blood cell count (WBC) is generally accepted as a prognostic risk factor in acute myeloid leukemia (AML) outcome and displays a marked interindividual variation. The dose regimen currently used ignores the size of the tumor burden and the standardization of the dose is generally based on body surface area. In this study we have investigated the effect of cell density on the cytotoxic activity of daunorubicin (DNR) and cytosine arabinoside (AraC) towards HL60 cells and leukemic cells isolated from patients with AML. We demonstrate that drug cytotoxicity decreased with cell density and that apoptosis induction by DNR in isolated leukemic cells was greatly reduced at higher cell density. A marked reduction of the uptake of DNR and AraC in HL60 parental and mitoxantrone resistant cells was observed with increasing cell density. Such a drug depleting effect by cells at high density has been previously described for vincristine, doxorubicin and paclitaxel. By extrapolating the in vitro results to the in vivo situation, one could hypothesize that a high WBC can lower the plasma concentration through high uptake in the tumor burden, leading to a shortage of drug in leukemic blasts. Patients with high WBC might therefore benefit from a dose increase of DNR and/or AraC.     

Irradiation of platelet components: inhibition of lymphocyte proliferation assessed by limiting-dilution analysis

BACKGROUND: Using a limiting-dilution analysis (LDA) assay that measures clonigenic T cells, it has been demonstrated that, with 2500 cGy, there is no T-cell growth in red cell components irradiated in blood bags. In the current study, the LDA assay was used to investigate the effect of gamma radiation on the proliferative capacity of T cells in plateletpheresis components. STUDY DESIGN AND METHODS: Platelets were collected by using an apheresis instrument and settings that provided sufficient mononuclear cells for the LDA assay. Platelet components (n = 8) were irradiated in 1-L plastic bags 24 hours after collection with 500, 1500, and 2500 cGy of gamma radiation in a stepwise manner. Mononuclear cells were isolated after each irradiation dose by the use of ficoll-hypaque. A density separation medium was used to reduce the platelet numbers. T cells were enumerated by fluorescence-activated cell sorter and functionally assessed by LDA assay, which quantified T cells proliferating in the presence of polyclonal stimuli and cytokines. The frequency of T-cell growth (f) was visually scored after 4 weeks of incubation at 37 degrees C. Data were calculated as f(experimental)/f(control) and expressed as log(10) reduction. RESULTS: The T-cell content of the mononuclear cell population was 17 +/- 10.5 percent, which was unaltered by irradiation. After 500-cGy irradiation, functional T cells were reduced by 2.09 log(10). Irradiation with 1500 cGy resulted in a 3. 96 log(10) reduction, but viable clonable T cells were detected in all experiments. With 2500-cGy irradiation, no T-cell growth was detected; this represented a greater than 4.86 log(10) reduction. CONCLUSION: As the dose of gamma radiation delivered to plateletpheresis components increased, the number of residual functional T cells decreased exponentially. Irradiation with 2500 cGy inactivates T cells in apheresis platelets, as measured by an LDA assay.