恶性肿瘤稳定期与转移期血小板变化

 目的 探索恶性肿瘤由稳定期发展至转移期的血小板变化规律,筛选转移期的血小板截断值.方法 回顾性分析30例经标准治疗后由稳定期发展至转移期的癌症患者转移前后的血小板计数,采用配对样本1检验分析血小板变化与发生转移的关系;通过绘制ROC曲线图,找出转移期血小板的临界值.结果 患者转移期血小板计数增高,稳定期和转移期血小板差异有统计学意义(P＜0.05);转移期血小板截断值为271×109/L,其灵敏度为64％,特异度为95％.结论 恶性肿瘤由稳定期发展至转移期时血小板计数呈明显升高趋势.血小板计数＜271×109/L时,其发生转移的可能性较小;而血小板计数＞271×109/L时,应考虑病情恶化的可能性.     

The postmortem activation status of platelets

Platelets are activated by substances from the subendothelial matrix in endothelial lesions or by factors in the plasma coagulation cascade. Conversely, activated platelets are potent activators of this cascade. Only activated platelets express the adhesion molecules Gp53, GMP140 and thrombospondin on the plasma membrane. The postmortem activation status of platelets, therefore, can be determined immunoelectron microscopically by immunogold labeling of antibodies against these glycoproteins. Our studies revealed that the vast majority of these antigens were located within the granules post-mortem, hence the platelets had not been activated. Thrombin-induced activation of platelets in vitro was only possible in the early postmortem interval, as demonstrated by labeling of the adhesion molecules on the plasma membrane. Later, such activaton was no longer possible even though thrombin-induced fibrin formation gave the appearance of coagulated blood. In forensic medicine, these findings can possibly be applied to distinguish intravital clotting from the postmortem coagulation phenomena and intravital hematomas from postmortemhematomas.     

血小板保存专用塑料血袋的储存性能评价

目的：以美国Gambro BCT公司生产的Trima set血小板保存袋为对照,评价山东威高集团医用高分子制品股份有限公司生产的血小板保存袋对单采血小板的储存性能。方法将1U单采血小板平分成两份,分别加入实验血袋和对照血袋中,于血小板恒温振荡保存箱中保存。分别于保存0、3、5、7d取样,比较分析两组的血小板含量和血小板平均体积、pH值、体外聚集活性、氧分压和二氧化碳分压、葡萄糖、乳酸和乳酸脱氢酶浓度、低渗休克反应、血小板活化和凋亡、血小板形态结构及细菌培养试验。结果两种保存袋保存的血小板在保存期内,相同保存时间实验组与对照组之间各项检测结果差异无统计学意义（P＞0．05）;无菌试验均为阴性。结论国产血小板专用塑料血袋与美国Trima set血小板保存袋对该实验使用的15份单采血小板具有相似的储存性能。     

肝移植患者围术期血小板及其检测参数分析

 目的 探讨肝移植患者围术期血小板及其参数的变化规律和肝移植术后血小板减少的原因及监测血小板参数的临床意义.方法 分别检测我院实施肝移植患者200例术前1 d及术后1、2、4、6、8、10、12、15 d的PLT、MPV、PDW、P-LCR四项参数.以术后15 d内PLT尚未恢复正常的44例(未恢复组)与恢复正常的156例(恢复组)进行对比分析.结果 未恢复组术前PLT明显低于恢复组(P＜0.01),PDW、MPV、P-LCR两组无明显差异(P＞0.05).未恢复组和术前比较,术后第4天PLT为最低,而后略有回升,但直至第15天仍未恢复正常.恢复组和术前比较,术后第6天PLT最低,而后逐渐回升,直至15天基本恢复正常.从术前至术后15天,恢复组PLT均高于未恢复组(P＜0.05).PDW两组术后亦无明显差异(P＞0.05).术后未恢复组随着PLT的降低,MPV、P-LCR进一步降低,恢复组随着PLT的降低而MPV、P-LCR却升高,两组差异显著(P＜0.05).结论 P-LCR、MPV对判断肝移植术后血小板减少原因是重要的指标之一.血小板及其参数的监测对肝移植术后病情变化的判断有一定参考价值.     

Cardiorespiratory fitness in groups with different physical activity levels

The aim of the study was to determine how different categorizations of self‐reported and objectively measured physical activity (PA) reflect variations in cardiorespiratory fitness (VO_2max). A total of 759 individuals (366 women) with a mean age of 48.5 years (SD 14.4) wore an accelerometer (ActiGraph GT1M) for seven consecutive days and answered the short International Physical Activity Questionnaire (IPAQ). VO_2max was directly measured during a continuous graded exercise treadmill test until exhaustion. Men and women categorized as highly active by IPAQ had 9% and 13% higher VO_2max, respectively, than those reporting a low PA level (P < 0.05). Men and women meeting the PA recommendation of 150 min/week of daily moderate intensity PA, measured by accelerometer, had 13% and 9% higher VO_2max, respectively, than participants not meeting this recommendation (P < 0.01). No significant differences in average sedentary time, analyzed in total min/day and in bouts of 10 and 30 min, were found between participants with high or low cardiorespiratory fitness. However, women spent less time than men in bouts of sedentary behaviors. Self‐reported PA by IPAQ and objectively measured PA by accelerometer were both useful instruments for detecting differences in VO_2max.     

异硫氰酸荧光素掺入法测定mPEG修饰的红细胞半寿期

目的：为甲氧基聚乙二醇(mPEG)包裹改造红细胞制备通用型血实验提供一种简便、可靠、安全无污染的红细胞半寿期测定方法。方法：用异硫氰酸荧光素(FTTC)标记、mPEG包裹小鼠红细胞，然后回输到小鼠体内，用流式细胞仪测荧光标记的细胞百分含量，计算红细胞半寿期。结果：mPEG包裹对红细胞膜上异硫氰酸荧光素荧光强度的检测没有影响，异硫氰酸荧光素的衰减也不会影响红细胞半寿期的测定。低剂量的mPEG包裹不影响红细胞的寿命，而高剂量的mPEG包裹会对红细胞产生损伤，使其寿命明显缩短。结论：此方法简便，易操作，安全无污染，是一种可行的测定红细胞半寿期的方法。     

Functional alterations of human platelets following 111In labeling with different ligands and incubation media

We studied the effects of various 111In-water soluble chelates and incubation media on labeling efficiency of platelets and in vitro platelet aggregability. High labeling efficiency of platelets in ACD-saline was achieved with 111In-oxine sulfate, 111In-tropolone and 111In-MPO (2-mercaptopyridine-N-oxide). In the condition with 4.8 x 10(6)/mm3 platelets in ACD-plasma, 111In-oxine-sulfate had low labeling efficiency and inconsistent labeling, while 111In-tropolone and 111In-MPO had high labeling efficiency. In vitro platelet aggregability (ADP 2 microM) was reduced when platelets were labeled in the absence of plasma. However, there was no significant difference in platelet aggregability among 111In-platelets labeled by three different chelates. In conclusion, to maintain aggregation activity of the platelets with relatively high labeling efficiency, the best result was obtained by using MPO or tropolone chelate in plasma at 4.8 x 10(6)/microliters platelet concentration.     

The statistical evaluation of DNA mixtures with contributors from different ethnic groups

The effect of a structured population on the evaluation of forensic mixed stains has been considered by the authors and others. However, in countries with multiple racial or ethnic groups, it is not uncommon that contributors to a DNA mixture are of different ethnic groups. A famous example is the OJ Simpson case in which the suspect was an African-American, the victims were Caucasian Americans and the true perpetrator(s) could be from any ethnic group(s). In this paper six common mixture cases are considered and the formulae for likelihood ratios are derived. These formulae can help forensic DNA scientists acquire a better understanding of the problem. The effect of different ethnic groups is illustrated using a case in Hong Kong.     

111In-tropolonate labelled platelets; studies in normals and in patients with thrombocytopenia

Human platelets were labelled with aqueous ¹¹¹In-tropolonate in comparison with ¹¹¹In-oxinate. In normals the labelling efficiency with ¹¹¹In-tropolonate was higher (93%±2%) than with ¹¹¹In-oxinate (67%±8%) (P<0.05). In cases of severe thrombocytopenia, lower labelling efficiencies were obtained. In six normals a mean platelet life of 9 days ±3 days and an initial recovery of 59%±15% were obtained. In twelve patients with trombocytopenia the mean platelet life was 4 days±4 days and the initial recovery was 58%±20%. The absolute uptake of radioactivity in spleen and in liver in both groups are reported.