Safety of blood donations following a natural disaster

To evaluate the relative safety of blood donations given in response to a major disaster, donor demographics and infectious disease test results were compared for donations made during the 10 days following the October 17, 1989, San Francisco Bay Area earthquake and those made during the preceding 6 months. These comparisons were made for donations given to the regional blood center in the area that was immediately affected by the disaster (Irwin Memorial Blood Centers) and for those given in an unaffected region (Los Angeles/Orange Counties Region, American Red Cross Blood Services). The rate of donation increased more than 200 percent during the 5 days following the earthquake in both the disaster-affected and unaffected regions. Both the disaster-affected and unaffected regions observed significant increases in the proportions of donations by first-time donors, by persons aged 20 to 39 years, and by women. The rates of confirmed positivity for infectious disease markers for post-earthquake donations did not differ significantly from rates for homologous donations given during the preceding 6 months, particularly when the rates were adjusted for the increased representation of first-time donors. Approximately 39 percent of post-earthquake first-time donors gave blood again within the following 6-month period. It is concluded that donations given after major disasters are essentially as safe as routine donations and that active efforts to recruit these donors again can be undertaken without reservation.     

大学生自尊特点与性别、年级及心理因素的关系

目的:观察大学生自尊水平的特点。方法:于2005-11/2006-05选取江西省内6所高等院校,专业包括理工科、医学、师范类及文科类大学生793名。以751名大学生为研究对象,采用二维自尊量表进行调查,包含16个题项,每个维度8个题项。量表的重测信度为0.84和0.80,同质性信度为0.86和0.84;该量表测量整体自尊,分为自我喜欢和自我能力感两个维度。采用个别访谈的方法对自尊高分同学和自尊低分同学进行个别访谈,同时收集同学和班主任(辅导员)对该同学的评价。调查中使用半结构化访谈,访谈提纲的内容是依据症状自评量表各因子结合以往研究中自尊及其相关影响因素设计的,主要包括以下3个方面:①与焦虑有关的认知和事件。②与同学、老师以及朋友的关系。③对自我情感和心境的评价。为了缓解被访谈者的紧张情绪,还进行其他方面的交流。结果:发放问卷793份,收回780份。对所收回的问卷进行初步整理,剔除不符合要求的废卷后,获得有效问卷751份。①男生在整体自尊和自我能力感维度上得分高于女生,差异有显著性意义[分别为(49.5820±7.9979),(48.2091±8.2642)分;(23.3893±3.9680),(22.6963±4.2606)分,t=2.157,2.134,P<0.05]。男女生在自我喜欢维度上得分差异无显著性意义(P>0.05)。②在整体自尊和自尊两个维度上,各年级之间差异有显著性意义(P<0.05)。大二学生自我喜欢维度得分明显高于大一和大三学生[分别为(26.7353±5.1527),(25.2432±4.7695),(25.6045±5.2917)分,t=3.485,2.11,P<0.05,0.01];大二学生在自我能力感维度得分明显高于大一和大三学生[分别为(23.5588±4.2219),(22.5459±4.2285),(22.9718±3.9448)分,t=2.748,1.395,P<0.05,0.01]。③整体自尊和自尊两个维度,在性别与年级之间有交互效应。整体自尊和自我喜欢得分男生高于女生,大二学生得分高于大一和大三学生。自我能力感得分大二女生高于男生。在整体自尊和自尊两个维度,年级和专业之间有交互效应。④自尊与心理健康的关系:整体自尊高分者普遍具有正确的人生态度,满意的心境,对生活乐观,对未来充满了希望,和谐的人际关系、良好的个性和高尚的人格,同学之间关系融洽,能很好地相处,在与人交往中能做到尊重人、理解人,从不将自己的观点强加到他人的身上,能够平等地、宽容地了解、评价对方。而整体自尊低分者普遍存在焦虑情绪,人际关系不和谐和不能恰当地认同自己,或是莫名其妙地自傲,或是无缘无故地自卑,经常有意无意地掩饰自己的不足,心理特别敏感、脆弱,失落感极强,经不起风浪的折腾,存在严重的心理冲突,回避矛盾,无法保持平衡的心理状态。结论:大学生自尊水平存在性别、年级差异,并与心理健康症状存在明显相互作用关系。     

Rapid freezing of whole blood or buffy coat samples for polymerase chain reaction and cell culture analysis: application to detection of human immunodeficiency virus in blood donor and recipient repositories. The Transfusion Safety Study Group

Storage of lymphocytes for later use in prospective epidemiologic studies of blood donors and transfusion recipients has been limited by the cost of separating peripheral blood mononuclear cells (PBMCs). When the Transfusion Safety Study began in 1985, it was decided to establish a cell repository of cryopreserved buffy coat (BC) samples, and thus far over 20,000 samples have been accumulated from enrolled subjects. To determine if these specimens could be used for polymerase chain reaction, a simple thawing and pelleting technique for recovering hemoglobin-free total white cells (WBCs) was developed. To validate the technique, parallel analysis was conducted of BCs, whole blood (WB), and PBMC samples from human immunodeficiency virus type 1 (HIV-1)- seropositive subjects. Immediate postthaw cell courts of 29 frozen- thawed (F-T) WB and BC samples averaged 90 percent of the prefreeze (input) values. Representative WBC populations were obtained by immediate pelleting. Amplification of HIV-1 gag sequences from F-T BCs and F-T WB was 94 and 75 percent, respectively, which is as sensitive as that obtained with freshly separated PBMC lysates. Quantitative HIV- 1 proviral load analysis by serial dilution of 23 F-T BCs and 8 WB lysates showed results comparable to those obtained with lysates of fresh PBMCs. Values for WBC differential and immunophenotyping could be applied to express viral load relative to total WBCs, PBMCs, or CD4+ cells. These results establish the basis for simplified virologic analysis of cryopreserved BC or WB specimens.