脐血有核细胞移植治疗脑卒中的动物实验

目的:脐血有核细胞中富含多系前体细胞,具备改善受损神经系统功能的潜能。为此建立阻塞性脑卒中动物模型,探讨脐血有核细胞移植对其治疗的可行性。方法:实验于2004-09/2005-05在深圳市宝安区人民医院动物实验室完成。①实验材料:脐带血取自足月新生儿,由深圳宝安血站研究室提供,产妇及其家属均签署知情同意书。SD清洁级成年大鼠80只,随机取20只作为正常对照组,另60只以电凝法建立阻塞性脑卒中模型。剔除运动功能障碍不典型鼠后,随机取5只作为模型观察,余鼠按1∶1随机分为细胞移植组和模型对照组,当出现单只为尾数时,将其分配在细胞移植组。②实验方法:无菌抽取脐血20mL,加入乙二胺四乙酸抗凝,Ficoll法分离脐血有核细胞。造模后第10天,细胞移植组大鼠将头部固定,按前囟尾侧3.0mm,中线旁1.5mm,深度1.2mm注入1011L-1脐血有核细胞悬液5μL,1μL/min。模型对照组注射等量无细胞脐血清,正常对照组不给予任何干预。③实验评估:造模后4周,5只模型观察大鼠制作脑切片,行苏木精-伊红染色镜检。各组分别于细胞移植前、细胞移植后2,6周进行横木行走实验和触觉刺激试验,检测其运动和触觉功能的恢复。处死各组大鼠制作病理切片,免疫荧光检测脐血有核细胞在脑内生存和分化情况。结果:正常对照组、细胞移植组、模型对照组各20只、24只、24只进入结果分析。①阻塞性脑卒中模型大鼠病理特征:造模大鼠出现行为障碍,缺血部位出现中风囊,病理切片可见缺血坏死区等阻塞性脑卒中所致脑组织病理损伤。②运动和触觉功能测试:细胞移植前,细胞移植组与模型对照组大鼠的横木行走能力、撕胶纸能力均基本相似(P=0.05),且明显低于正常对照组(P<0.01)。移植后第2周,细胞移植组大鼠两项能力均明显强于模型对照组(P<0.05),但仍低于正常对照组(P<0.01)。移植后第6周,细胞移植组大鼠的横木行走能力明显改善,与正常对照组基本相似(P>0.05);撕胶纸能力仍低于正常对照组(P<0.01)。③阳性细胞免疫荧光检测:细胞移植组进针注射部位存在大量抗人RNP/CD45双阳性完整细胞,并向大脑中线、皮层梗死部位迁移。所植入的细胞约2.95%表达胶质纤维酸性蛋白,3.41%表达神经特异性烯醇化酶。结论:移植人脐血有核细胞能有效改善阻塞性脑卒中大鼠的运动和触觉功能缺陷。     

Blood collections by community blood centers, 1988 through 1992

BACKGROUND: The provision of a safe and sufficient supply of blood is critical to patient care. STUDY DESIGN AND METHODS: A survey was conducted of the blood collection activity of the 189 community blood centers operating in the United States from 1988 through 1992. Data were analyzed by source of the donation (allogeneic or autologous), by center's collection volume, and by geographic region. Total collection figures were compared to historical blood collection activity since 1970. RESULTS: A total of 12.31 million units of blood were collected in 1992, an increase of 2.6 percent over the total number of units collected in 1988. For the 5-year period (1988-1992), total collections increased at a compound annual growth rate of 0.6 percent. The collection of allogeneic blood units declined by 0.2 percent annually, while that of autologous units increased by 23.2 percent annually. Autologous blood units accounted for 5.7 percent of total collections in 1992. Nationally, 48 units were collected per 1000 people in 1992, although substantial geographic variation (range, 38–64 units/1000) was observed across nine US census regions. CONCLUSION: The data from this study provide evidence that the total supply of blood grew more slowly from 1988 through 1992 than in the years before 1988.     

CLIMACTERIC SYMPTOMS IN HEALTHY MIDDLE-AGED WOMEN

SUMMARY The incidence of climacteric symptoms was determined in 247 healthy premenopausal women in a community setting. These volunteers had been recruited to a longitudinal study of bone density. Of these subjects, 46 ceased to menstruate during the study, and in this subgroup symptoms were compared before and after cessation of menstruation. Only hot flushes increased after cessation of menstruation in the longitudinal study and showed age correlation in the cross-sectional study. Hot flushes thus emerged as a true menopausal symptom. Although evidence for this is weaker, cold sweats and suffocation seem likely to be genuinely menopausal. Breast discomfort and the four mood symptoms of irritability, excitability, depression and poor concentration improved after cessation of menstruation, and this study gives no support for their being part of the menopausal syndrome; it suggests that these symptoms are more likely to be related to menstruation than to the menopause.     

A one-step Du test in microplates

A one-step Du test, developed for use in automated microplate systems, uses anti-D with 0.6 percent dextran to potentiate the reaction. Because the washing and reagent-adding steps of the antiglobulin test are not required, the Du test can be performed in the same microplate as the ABO/Rh test. A set of reactions prepared with this technique was visually interpreted and also classified by an automated microplate ABO/Rh system. Visual interpretation of reactions resulted in a sensitivity and specificity close to those of the antiglobulin test, although the sensitivity of the test was reagent-dependent. When the automated microplate blood grouping system was used, the test was not as sensitive or as specific as the antiglobulin test, although it may be sufficient for many applications.     

DEEP HAND INFECTION COMPLICATING CHICKENPOX IN AN OTHERWISE HEALTHY INFANT

SUMMARY Chickenpox is a common childhood infection, and complications are rare in the healthy child. This report describes a significant complication of varicella in an otherwise healthy infant.     

Minimal number of circulating CD34+ cells to ensure successful leukapheresis and engraftment in autologous peripheral blood progenitor cell transplantation

BACKGROUND: The number of peripheral blood (PB) CD34+ cells has been widely used to monitor the timing of leukapheresis for autologous transplantation. However, no cutoff value for CD34+ cells in PB has been defined as a guideline for the identification of patients in whom the harvest would be effective and those in whom there was a high probability of failure. STUDY DESIGN AND METHODS: The present study investigated the best threshold of CD34+ cells in PB for successful harvesting and engraftment, using 263 PB samples with their corresponding leukapheresis components. In addition, that measure has been compared to other commonly used criteria such as the white cell count, the number of mononuclear cells, and the number of colony- forming units-granulocyte macrophage in PB. RESULTS : Time to engraftment of both granulocytes and platelets was significantly influenced by the number of CD34+ cells transfused, but all patients receiving > or = 0.75 × 10(6) CD34+ cells per kg achieved engraftment within a reasonable number of days (> 0.5 × 10(9)/L granulocytes by Day 11 and > 20 × 10(9)/L platelets by Day 13). A clear correlation between the number of CD34+ cells per microL in PB and of CD34+ cells per kg collected was found at each apheresis (r = 0.9, p < 0.0001). Moreover, the number of CD34+ cells per microL measured in PB the day the first leukapheresis was initiated displayed an excellent correlation with the total amount of CD34+ cells per kg finally collected (r = 0.81, p < 0.0001). On the basis of the regression curve obtained and the clinical engraftment results, it was found that the presence of > 5 CD34+ cells per microL in PB ensured a good yield from the harvest in 95 percent of patients and would avoid an unsuccessful harvest in 81 percent of cases. CONCLUSION: A dose of only 0.75 × 10(6) CD34+ cells per kg guarantees hematopoietic recovery within a reasonable number of days. To initiate a leukapheresis from which enough progenitor cells may confidently be obtained, a minimum of 5 CD34+ cells per microL in PB is required.     

Evaluation of platelet concentrates prepared from buffy coats and stored in a glucose-free crystalloid medium

Comparison was made between platelet concentrates prepared from pools of buffy coats removed from standard blood donations and stored in a glucose-free, commercially available crystalloid solution (BC-PCs) and standard platelet concentrates prepared from platelet-rich plasma (PRP-PCs). Platelet yield in BC-PCs and PRP-PCs was 59 and 75 percent of donated platelets, respectively. The number of total white cells in 1 BC-PC unit, prepared from a pool of 7 buffy coats, was 21 x 10(6), i.e., 50 times lower than that of 7 units of PRP-PCs. The in vitro values of adequate platelet quality were maintained for 10 days in BC-PCs stored in 1000-mL polyolefin bags. Prolonged bleeding times were reduced or corrected in three of three thrombocytopenic leukemic patients evaluated before and after transfusion of stored BC-PCs. Pretransfusion and 1- and 24-hour posttransfusion median platelet counts in 57 leukemic recipients during 4 months of routine transfusion of BC-PCs (n = 93) were 14, 35, and 27 x 10(9) per L, while those of PRP-PCs (n = 246) were 13, 37, and 31 x 10(9) per L, respectively. No reactions to BC-PCs were reported, but a 1.3 percent rate of reaction to PRP-PC transfusions was reported. This study indicates that BC-PCs are a good alternative to PRP-PCs for platelet support of thrombocytopenic patients.