Platelet additive solutions: A future perspective

Platelet additive solutions (PASs) were first developed in the 1980s, and continued to be improved over the following years. The use of PASs as replacement for plasma has a number of benefits, both for the quality of the platelet concentrates and for the patients. However, some PASs have been associated with a lower platelet yield in the PCs, a shorter storage time, and a lower increment in the patient when compared to PCs in plasma. A number of reformulations of the PASs have taken place to counteract these disadvantages. Most PASs use acetate as nutrient for the platelets, which has the benefit of generating bicarbonate when oxidized by the platelets, thus supplying its own buffering capacity. Alternatively, glucose is used, but may cause deterioration of pH in the stored PCs due to the formation of lactic acid. Addition of other buffering substances, such as phosphate, can be added to ensure maintenance of neutral pH. An important finding was the inhibiting effect of potassium and magnesium on platelet activation. The initially developed PASs lacked these two ingredients and showed reduced storage times of the PCs in PAS when compared to those stored in plasma. However, when these constituents are included in the PAS, storage time is similar and even exceeds those seen for PCs in plasma. Considerable research is done in further formulating the optimal PAS. Bicarbonate is being considered as buffer for these PASs. Also, L-carnitine appears to have a favorable effect on stored platelets, including a reduction of platelet metabolism, and inhibition of apoptosis. Another area of optimization is lowering of plasma content needed for maintaining platelet quality. Where current PASs still need at least 30% residual plasma, there is a trend towards lowering the plasma content to less than 5% with the newer PASs. Preservation of purinergic platelet receptor functionality by ADP-degrading activities in plasma appears to play an important role in this respect. Development of PASs are usually based on in vitro studies alone. It is important to realize that only clinical studies can give definitive answers about the quality of platelets stored in PASs. Sofar, only limited clinical evaluations have been published that either studied the effectiveness of platelets in initially-developed PASs, or were specifically done in combination with pathogen reduction technologies. Thus, PASs seem to be an excellent replacement for (part of) the plasma when producing PCs, and allow extended storage with maintenance of quality, but more clinical studies are needed to substantiate in vitro results.     

33例精神分裂症患者氯丙嗪治疗前后血小板聚集功能

本文对精神分裂症患者用氯丙嗪治疗前后PAg(T)功能进行观察及BPRS评定,发现精分症患者PAg(T)功能明显高于对照组,用氯丙嗪治疗1个月后,BPRS评定分值下降,患者临床症状消除,而PAg(T)第一时相无变化,第二时相明显升高,说明氯丙嗪聚药物可促发血小板释放内源性致聚物质,同时也说明患者PAg(T)异常不仅仅是情绪应激所致,更重要的是血小板生理功能异常。     

体外循环对紫绀型先天性心脏病病人血小板的影响

检测１８例体外循环紫绀型先天性心脏病手术病人术前，术中及术后３，８天外周血血小数量和 附，聚集功能，探讨体外循环对血小板质和量的影响。结果显示，血小板数量和聚集功能在术后显著下降并持续至术后８天，血小板粘附功能显著下降，术后３天恢复。提示体外循环气血界面，人工材料非内皮表面可导致血小板激活，粘附，聚集面在量消耗，数量和功能显著下降。     

兔实验性急性重症减压病时血细胞的变化

目的观察实验性急性重症减压病过程中兔血液细胞计数的变化,比较存活组与死亡组动物各项指标的异同,分析重症减压病的致死机制。方法取14只新西兰白兔,使其在0.55 MPa下停留35 min,然后再继续加压,升至0.7 MPa时停留35 min,于4 min内匀速减压出舱。检测加压前、高压停留中、减压后兔血液白细胞(WBC)总数、中性粒细胞、淋巴细胞及血小板(PLT)计数。比较存活动物与死亡动物上述各指标变化的特点。结果经历匀速快速减压后,有8只兔在30 min内死亡,存活的6只兔经观察24 h后未遗留任何减压病症状。兔WBC总数加压前为(9.76±2.23)×109/L,0.55 MPa下停留30 min后,降至(8.15±2.20)×109/L,而减压后,则增加至(13.14±4.75)×109/L。PLT数于0.55 MPa下停留30 min后较加压前无明显变化,减压后,由加压前的(584.36±142.34)×109/L降至(380.43±162.42)×109/L。加压前,死亡组动物血液WBC总数为(11.13±2.37)×109/L,明显高于存活组动物(8.87±2.11)×109/L,且以中性粒细胞为主。减压后死亡组动物PLT减少了(273±63)×109/L,存活组的动物PLT减少了(148±63)×109/L,两组间比较,差异有显著性(P<0.05)。结论高压下停留可造成兔血液中白细胞数下降,而快速匀速减压则引起WBC升高和PLT下降。死亡组动物加压前WBC总数及减压过程PLT减少量均大于存活组动物。提示,白细胞和血小板参与重症减压病致死机制。     

In-vivo evaluation of random donor platelet concentrates from pooled buffy coats

 Random-donor platelet concentrates (PC) prepared from pooled buffy coats have recently been described as an alternative method for platelet preparation. We evaluated such PCs in the clinical setting compared with a standard PC from platelet apheresis. PCs were prepared either from pools of buffy coats (BC-PC) or from single donors (SD-PC) with the cell separator CS-3000 plus. PCs were stored for up to 5 days before transfusion. We compared fresh PC (day 1) with stored (day 2–3) and long-stored PC (day 4–5). For analysis, platelet increment in the recipient was determined immediately and 16–22 h (mean 20 h) after transfusion, corrected for total body area and transfused platelets (CCI). A total of 316 PCs were administered to 36 thrombocytopenic patients suffering from various hematological disorders. Patients with detectable HLA or platelet-specific antibodies or splenomegaly were excluded from the study. Mean platelet content of the PC was 262×10⁹ for BC-PC and 251×10⁹ for SD-PC. The 20-h CCI after transfusion of fresh PC was slightly higher with BC-PC than with SD-PC (14.5 versus 11.9;p=0.19), but values did not differ significantly between the two types of PC on any day of storage. For BC-PC, 20-h CCI decreased with further storage by 30% (10.2;p=0.02). For SD-PC a decrease by 9% was not significant. In conclusion, platelet concentrates prepared from pools of buffy coats showed excellent transfusion results when administered fresh, but storage decreased the CCI by 30%. No significant difference from PCs from plateletpheresis was observed on any day of storage. Both types of platelet concentrates were capable of sufficient platelet increment even when stored for up to 5 days. Received: 28 December 1995 / Accepted: 14 May 1996     

PAF antagonistic activity of 2-hydroxy-3-methoxybenzoic acid glucose ester fromGentiana scabra

In order to find out anti-platelet activating factor (PAF) from natural resources, Korean medicinal plants used for the treatments of peripheral circulation disorders were tested for their possible protective effects on PAF-induced anaphylactic shock. From the above screening, the methanol extract ofGentiana scabra showed a potent antagonistic activity against PAF. Water suspension of the extract was partitioned with CH₂Cl₂ and EtOAc, successively. The EtOAc fraction which showed the highest activity was chromatographed on silica gel to yield 6 fractions. From the fraction which showed higher PAF-antagonistic activity than the other fractions, compound1 was isolated by recrystallization. On the basis of spectral data, compound1 was identified as 2-hydroxy-3-methoxybenzoic acid glucose ester. The compound prevented the mice from the PAF-induced death at a dose of 300 μg/mouse.     

血小板活化因子、癌胚抗原、糖类抗原724在结直肠癌中的表达及与临床病理特征的关系

目的:探讨血小板活化因子(PAF)、癌胚抗原(CEA)、糖类抗原724(CA-724)在结直肠癌(CRC)患者术前血清中的阳性表达率及与临床病理特征的关系、发病的独立危险因素。方法:选取2019年12月至2021年10月于包头医学院第一附属医院就诊的CRC患者75例为CRC组,另选取同时期在本院体检的健康志愿者75例为对照组。采用酶联免疫吸附(ELISA)法分别检测CRC患者术前及对照组的晨空腹外周静脉血PAF含量;回顾性分析上述入组患者术前血清CEA、CA-724含量,进行统计分析。结果:(1)CRC组PAF、CEA、CA-724单独检测和联合检测的阳性率分别为25.33%、42.67%、30.67%、74.67%,均高于对照组,且联合检测的阳性率均高于单独检测指标的阳性率,组间差异均具有统计学意义(P<0.05);(2)单因素方差分析结果显示,血清CEA表达水平的影响因素为患者的淋巴结转移(P<0.05);血清CA-724表达水平的影响因素为患者的年龄(P<0.05);(3)二元Logistic回归分析结果显示,PAF表达在临床病理特征之间的差异无统计学意义(P&...     

S-99和S-100止血作用研究

PT、APTT、TT、血小板粘附率和血栓形成试验表明S-99可溶性止血纺织材料和S·100吸收性止血綾的止血效果无显著差异。但是S-99和S-100止血纺织材料的止血机理不尽相同,S-100止血绫主要是通过溶解后的负电性液相激活内源性止血系统;而S-99止血纺织材料主要是通过溶胀胶粒粘附血小板,进而激活血小板。     

白细胞促凝物质的实验研究

以新鲜全血制备白细胞冻溶上清液，进行其促血小板聚集和促凝血时间的对照研究。结果发现，临床甲襞微循环检查具有白色微小血栓的患者血小板聚集率明显增高及凝血时间缩短明显（P＜0．001），证实白细胞确有促凝物质的存在并参予了白色微小血栓的形成。