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1.
Todd M. Getz 《Transfusion and apheresis science》2019,58(1):12-15
Platelet transfusions are a life-saving medical intervention used for the treatment of thrombocytopenia or hemorrhage. Extensive research has gone into trying to understand how to store platelets prior to the transfusion event. Much has been learned about storage bag materials, synthetic solutions, and how temperature impacts platelet viability and function. While room temperature storage of platelets preserves 24-hour in vivo platelet recovery and survival there is a greater risk for bacterial growth. Therefore, cold storage of platelets has become attractive due to the reduction in potential bacterial proliferation and the maintenance of platelet function beyond 5 days of storage. Cold stored platelets, however, have their own set of challenges. Cold stored platelets become activated through several mechanisms. The morphological and molecular changes that occur due to cold exposure enhance their ability to participate in the hemostatic process at the cost of rapid clearance from circulation. This review focuses on the underlying mechanisms leading to cold platelet activation and the receptor modifications involved in platelet clearance. 相似文献
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《中国现代医生》2020,58(14):5-8
目的研究经导管动脉化疗栓塞(TACE)对原发性肝癌患者的疗效及中性粒细胞/淋巴细胞计数比(NLR)、血小板/淋巴细胞计数比(PLR)的影响。方法选择2015年6月~2019年1月我院接诊的原发性肝癌患者80例作为研究对象,采用随机数表法将患者分为两组,每组各40例。对照组予传统肝切除术治疗,观察组采用TACE治疗。对比两组治疗后的临床效果,NLR、PLR、癌胚抗原(CEA)、可溶性B7-H4、可溶性白细胞介素-2受体(sIL-2R)及并发症发生情况。结果治疗后,两组患者的总有效率分别为75.00%和52.50%,观察组高于对照组,差异有统计学意义(P0.05);治疗前,两组患者NLR、PLR水平对比,差异无统计学意义(P0.05);治疗后,患者NLR、PLR水平下降,观察组低于对照组,差异有统计学意义(P0.05);治疗前,两组患者CEA、B7-H4、sIL-2R水平对比,差异无统计学意义(P0.05);治疗后,两组患者CEA、B7-H4、sIL-2R水平下降,观察组低于对照组,差异有统计学意义(P0.05);两组患者并发症发生率分别为17.50%、40.00%,观察组低于对照组,差异有统计学意义(P0.05)。结论在原发性肝癌患者中使用TACE效果显著,可有效改善患者肿瘤标志物水平,减少并发症,值得推广应用。 相似文献
4.
《Transfusion and apheresis science》2020,59(5):102868
The novel coronavirus disease (COVID-19) has been declared a pandemic by the world health organization and to limit the spread of the disease, many countries in the world, including India, had enforced a lockdown. Despite no restriction over the platelet donation activities, plateletpheresis donors became apprehensive regarding the possible risk of spread of the COVID-19 during the platelet donation and in the hospital premises. Many of them started hesitating for platelet donations. With this, the blood center started having an acute shortage of platelets. Various confidence-building steps were implemented by the blood center to promote voluntary plateletpheresis. The blood center staff and individual donors were educated to prevent the spread of COVID-19. The donor organizations and plateletpheresis donors were informed about the steps to be taken by the blood center during the donation and necessary steps for the prevention of the possible spread of COVID-19. With the help of these measures, the confidence of the individual platelet donors and the donor organizations was restored in the blood center and regular plateletpheresis was continued. These measures may also be useful to other blood centers in the COVID-19 pandemic and this experience may be useful if a similar pandemic lockdown happens in the future. 相似文献
5.
目的探讨血小板第4因子(platelet factor 4,PF4)对5.0 Gy γ射线全身照射小鼠的骨髓基质细胞(bone marrow stromal cells,BMSCs)的保护作用,进一步探讨PF4对造血的辐射防护机制.方法30只雄性小鼠随机分为3组:①放射组,②PF4保护组,③对照组.小鼠照射前分别于26和20 h腹腔内注射PF4,每次剂量50 μg/kg.于照射后3 d取骨髓细胞体外培养,分别计数培养后3、7和14 d的骨髓基质细胞集落(CFU-F);在培养后10 d流式细胞仪检测细胞周期.结果3组中,照射组3 d的CFU-F数量与PF4保护组差异无统计学意义,7和14 d的CFU-F数量PF4保护组较照射组明显增加.流式细胞仪检测结果表明3组中照射组G0+G1期细胞明显高于其余两组,S,G2+M期细胞明显低于其余两组.结论PF4对照射小鼠的骨髓基质细胞有保护作用,促进造血重建. 相似文献
6.
老年脑梗死患者急性期血小板活化功能定量检测 总被引:11,自引:2,他引:9
目的 :探讨老年脑梗死患者外周血中血小板膜糖蛋白变化的临床意义。 方法 :应用流式细胞术检测了 6 8例急性期老年脑梗死患者外周血血小板活化分子标记物CD4 1、CD6 2p和CD6 3的含量水平 ,与 4 2例正常老年人对照 ;并对脑梗死组病灶大小、梗死部位、病情分级等与血小板活化分子表达的变化进行分析 ,应用统计学进行处理。 结果 :急性期脑梗死患者血小板粘附分子CD4 1、CD6 2 p和CD6 3的表达水平显著高于正常对照组 (P <0 .0 1) ,且与梗死灶大小及病情分级密切相关 ,与梗死部位无关。 结论 :老年脑梗死患者急性期外周血血小板活化功能明显增强 ,为早期应用抗血小板聚集药物的治疗提供了实验依据 相似文献
7.
Objectives To investigate the relationship of the GPIa C807T dimorphism to the risk of myocardial infarction (MI) in Chinese. Methods We did a case-control study including 100 patients and 110 controls with same race. An allele-specific polymerase chain reaction (PCR) was used for genotyping of C807T polymorphism. Results An apparent association was found between the T807 allele and MI among individuals younger than the mean age of 60 years (odds ratio,2.49; 95% confidence interval, 1.08 ~ 6.22 ). The T807 allele remained an independent risk factor for MI when age, sex, smoking, hypertension, diabetes, bodymass index, LDL-cholesterol and HDL-cholesterol were adjusted by logistic regression. Conclusions GPⅠa T807 appears to be an independent risk factor for MI. 相似文献
8.
目的观察急性冠状动脉综合征患者介入治疗后血小板活化指标CD62p、CD63及糖蛋白Ⅱb/Ⅲa受体复合物及内皮功能的改变。方法60例急性冠状动脉综合征患者在冠状动脉介入术前和术后即刻以及次日采用流式细胞仪检测血小板活化指标CD62p、CD63及糖蛋白Ⅱb/Ⅲa受体复合物;双抗体夹心固相酶联免疫吸附试验测定血浆假血友病因子的表达水平;放射免疫测定法测定血浆内皮素1表达水平;酶法测定血浆一氧化氮的含量;彩色多谱勒超声诊断仪测量内皮依赖性血管舒张功能。选择健康体检者和稳定型心绞痛患者各30例作对照,观察急性冠状动脉综合征患者冠状动脉介入前后指标的变化并与对照组比较。结果与健康对照组和稳定型心绞痛组比,急性冠状动脉综合征组CD62p、CD63及糖蛋白Ⅱb/Ⅲa受体复合物明显增高(P<0.05或0.01);急性冠状动脉综合征患者介入术后即刻CD62p、CD63和糖蛋白Ⅱb/Ⅲa受体复合物与术前相比明显增高(P<0.01),但术后24h较术前无明显变化(P>0.05)。与健康对照组和稳定型心绞痛组比,急性冠状动脉综合征组假血友病因子、内皮素1的表达水平明显增高(P<0.01),内皮依赖性血管舒张功能和一氧化氮降低(P<0.05或<0.01);急性冠状动脉综合征患者介入术后即刻血浆假血友病因子和内皮素1水平升高(P<0.05或P<0.01),内皮依赖性血管舒张功能和一氧化氮水平降低(P<0.05),且介入术后24h假血友病因子水平也较术前升高(P<0.05),内皮依赖性血管舒张功能降低(P<0.05),但内皮素1和一氧化氮水平与术前差异无显著性(P>0.05)。结论血小板活化和内皮功能的损伤在急性冠状动脉综合征发生和发展过程中起重要的作用,冠状动脉介入术后血管内皮受到一定损伤,血小板有一定程度的激活。 相似文献
9.
血小板活化因子在急性肝肾衰竭动物模型中对肾功能的影响 总被引:1,自引:0,他引:1
目的:了解血小板活化因子(PAF)在急性肝、肾衰竭动物模型中对肾功能的影响及可能的作用机制。方法:设4组大鼠,分别注射D-氨基半乳糖(D-GaLN)加内毒素(LPS),D-GaLN加PAF,D-GaLN加LPS加PAF受体拮抗剂及生理盐水,诱导急性肝、肾衰竭动物模型,测肝、肾功能指标并观察肝、肾组织病理改变。结果:注射D-GaLN大鼠的血清丙氨酸氨基转移酶、总胆红素比生理盐水组升高10倍以上,差异有显著性,病检有肝细胞坏死。注射PAF或LPS组与PAF受体拮抗剂组或生理盐水组比,肾功能指标差异有显著性。肾组织病检可见部分肾小管坏死。结论:PAF与急性肝、肾衰竭动物模型中的急性肾衰有关;PAF可能参与了内毒素相关的肝肾综合征(HRS)的形成;PAF受体拮抗剂对HRS可能有治疗作用。 相似文献
10.
In rabbit platelet rich plasma (PRP), 5-hydroxytraptamine (5-HT,0.03~3μmol/L) induced decrease in light transmission (DLT) dose-de pendently with centralization, as revealed by electron microscopy. However, 5-HT did not induced platelet aggregation and release reaction. 5-HT-induced DLT was inhibited by methysergide (0.3~30μmol/L), indomethacin (0.3~10μmol/L) and PGE_1 (0.01~0.3μmol/L) in a dose-dependent manner, but not EGTA(0.3~3mmol/L). Collagen(Coll), arachidonic acid (AA), adenosine diphosphate (ADP) and a stable thromboxane A2 analoge(STA_2) also induced DLT before aggregation by themselves, which was also inhibited by PGE_1, but not inhibited by EGTA except for Coll However,Coll-, AA-, STA_2-and ADP-induced DLT were reduced by pretreatment of PRP with 5-HT dose-depen-dently. The duration of DLT by Coll and AA were decreased from 151.4±5.93 sec and 15(?)38±0.60sec to 45.44±4.04 sec and 9.00±1.25 sec respectively ((?)±s(?) P<0.01), but not by ADP and STA_2, 3μmol/L of ADP-and 0.3μmol/L of STA_2-induced aggregation which was not accompanied with release reaction were enhanced by 5-HT pretreatment, but in those (Coil 5μg/ml, AA 100~200μmol/L and STA_2 1~3 μmol/L) with release reaction, the amount of adenosine triphosphate(ATP)were suppressed significantly (P<0.001) by 5-HT pretreatment without the effect on the magnitude of aggregation, The mobilization of cytosolic free calcium concentration ([Ca~(2+)]i) was observed after 5-HT treatment in single washed platelet, the results indicated that the basic level of [Ca~(2+)] i was 64.78±3.24nmol/L and this level was increased dose-dependently and significantly at 30 sec after administration of 5-HT and the time of peak value of [Ca~(2+)] i was at 90~100 sec.The similar time courses of suppression of ATP released during aggregation, in cases of Coll(5μg/ml), AA (200μmol/L) and STA_2(3μmol/L), by 5-HT were also found in the present experiment. 相似文献