胆源性感染性休克兔血栓素、前列环素与血小板聚集率的变化

动态观察胆总管急性完全性梗阻并感染、继发休克兔的血浆血栓素(TXA_2)和前列环素(PGI_2)的稳定代谢产物 TXB_2和6-keto-PGF_(1α)含量及血小板聚集率的变化。结果,血浆 TXB_2呈进行性升高,20h 后(休克时)呈下降趋势,血浆6-keto-PGF_(1α)6h 升高,随后回降;血小板聚集率呈进行性下降。提示血栓素和前列环素、血小板聚集率的变化在重症急性胆管炎、胆源性感染性休克发病过程中起重要病理生理作用,与病情和预后转归有重要联系。     

RELATIONSHIP BETWEEN PLATELET CYTOSOLIC FREE CALCIUM CONCENTRATION AND PLASMA RENIN ACTIVITY

1. Plasma renin activity (PRA) and platelet cytosolic free calcium concentration ([Ca2+]i) were simultaneously determined in 18 untreated essential hypertensive subjects and 17 normotensive controls. A significant positive correlation was found between [Ca2+]i and PRA (slope = 42 nmol/l/ng/ml/h) in these 35 subjects. 2. Two determinations more than one week apart in nine subjects confirmed the parallel fluctuations of [Ca2+]i and PRA. A strict sodium restriction produced a progressive PRA elevation associated with a parallel rise in [Ca2+]i in one subject. 3. These results are consistent with the hypothesis that angiotensin II causes a concentration-dependent calcium mobilization.     

［5－（4－甲脒－苄基）－2，4－二氧代－咪唑烷－3－基］－乙酰基－L－天冬氨酰－L－缬氨酸的合成

根据由精氨酸－甘氨酸－天冬氨酸组成的肽能抑制血小板聚集的机制，设计并合成了［５－（４－甲脒－苄基）－２，４－二氧代－咪唑烷－３－基］－乙酰基－Ｌ－天冬氨酰－Ｌ－缬氨酸（９）。生物试验结果表明：（９）抑制血小板聚集作用最强，其活性以ＩＣ＿（５０）值相比，强于类似物。     

血小板衍生生长因子在肺鳞癌及肺腺癌中的表达及意义

目的　探讨血小板衍生生长因子 (PDGF)在肺鳞癌和肺腺癌中的表达及意义。方法　应用免疫组织化学技术观察了PDGF -A链和PDGF -B链在 42例肺鳞癌和 1 5例肺腺癌中的表达 ,并测定了它们在肺非特异性炎症组织中的表达。结果　PDGF -A链和PDGF -B链的表达主要定位于肿瘤细胞胞浆、血管内皮细胞及平滑肌细胞 ,炎症组织的肺泡上皮细胞及血管平滑肌细胞少量表达。PDGF -A链和PDGF -B链在肺鳞癌及肺腺癌中均有显著表达 ;PDGF的过度表达与肿瘤细胞的分化程度无关。结论　PDGF -A链和PDGF -B链的过度表达与肺鳞癌和肺腺癌有关 ;PDGF -A链和PDGF -B链的生物学特征可能有所不同 ,PDGF -B链与肿瘤微血管增生的关系可能更密切     

Prevalence and mechanism of streptokinase-induced platelet stimulation. Effect of acetylsalicylic acid.

It was recently shown that streptokinase may induce clot formation in vivo by immunoglobulin G mediated platelet stimulation. We evaluated the in vitro effect of streptokinase on platelet function in 103 subjects, of whom 52 were < or = 30 years and 51 were > or = 50 years old. Although streptokinase inhibited platelet aggregation in the majority of cases, in nine the threshold concentration of ADP required to induce irreversible aggregation decreased with streptokinase (1 million Units. l-1) by 30% or more. This observation was confirmed in five of the nine by repeated measurements indicating reproducible streptokinase-induced platelet stimulation. Among the five, two were < or = 30, and three were > or = 50 years old. In none of the five subjects did the radio allergo sorbent test detect type E immunoglobulins directed against streptokinase in the serum. In contrast, in four of the five subjects, streptokinase-induced platelet hyperaggregability was suppressed by addition of goat antibodies against human immunoglobulin G, or F(ab')2-fragments of such antibodies. Acetylsalicylic acid did not prevent streptokinase-induced platelet stimulation, but in three of five cases, led to an increase in the control threshold concentration for ADP, so that after the decrease induced by streptokinase the threshold concentration for ADP was in the same range as before acetylsalicylic acid and streptokinase administration. Thus, streptokinase led to an inhibition of platelet aggregation in the majority of subjects evaluated. In a minority of five out of 103, however, streptokinase reproducibly caused platelet stimulation, presumably mediated by immunoglobulin G.(ABSTRACT TRUNCATED AT 250 WORDS)     

山豆根碱与山豆根苏林碱对血小板聚集和粘附的影响

观察山豆根碱（Ｄａｕ）及山豆根苏林碱（Ｄａｓ）对人血小板聚集和粘附功能的影响，并探讨其作用机制。结果表明，两者可抑制由二磷酸腺苷、花生四烯酸和胶原引起的血小板聚集，药物浓度与聚集抑制率表现出明显的量效关系。Ｄａｕ处理的血小板其对二磷酸腺苷、花生四烯酸和胶原诱导聚集抑制的ＩＣ５０（ｍｍｏｌ／Ｌ）分别为０．０４２（ｎ＝５），０．０２８（ｎ＝９）及０．０４６（ｎ＝１０）；Ｄａｓ则分别为０．０４２（ｎ＝５     

吸入麻醉药对人血浆和血小板血栓素B2生成与血小板聚集的影响

目的：探讨吸入麻醉剂氟烷、安氟醚和异氟醚对人血浆血栓素Ｂ２（ＴＸＢ２），血小板ＴＸＢ２生成与血小板聚集的影响。方法：血浆ＴＸＢ２和血小板ＴＸＢ２的生成量用放免分析法测量，血小板聚集率用比浊法测量。结果：吸入１ＭＡＣ氟烷３０分钟后，血浆ＴＸＢ２浓度、二磷酸腺苷（ＡＤＰ）和肾上腺素（Ｅ）诱导的血小板ＴＸＢ２生成量与血小板聚集率显著下降，吸入１ＭＡＣ安氟醚３０分钟后，血浆ＴＸＢ２浓度和血小板ＴＸＢ２生成量与血小板聚集率亦显著下降，其降低的程度比氟烷轻。吸入１ＭＡＣ异氟醚对上述指标无明显影响。血小板ＴＸＢ２生成的减少与血小板聚集率的下降呈显著正相关。结论：氟烷显著抑制血小板聚集，安氟醚次之，异氟醚对血小板聚集无明显影响。其机制可能与氟烷和安氟醚通过抑制血小板上血栓素Ａ２受体的亲和力，降低ＡＤＰ和Ｅ诱导的血小板ＴＸＢ２的生成有关。     

冠心病不同临床类型患者血浆、血小板脂质过氧化损伤与TXA_2/PGI_2平衡的研究

作者观察98例正常人和109例不同临床类型冠心病人血浆、血小板LPO、SOD,SeGSHP_x,RBC—SOD及血浆TXB_2、6-keto-PGF_(1α)的变化,发现各型冠心病组均有LPO、PL—LPO、TxB_2、TxB_2/6-keto-PGF_(1α)比值明显升高,6-keto-PGF_(1α),SOD、PLSOD、RBC-SOD,SOD/LPO及SeGSHPX/LPO比值明显降低。但各型程度不同,以急性心肌梗塞和不稳定性心绞痛改变突出。血浆LPO与6-keto-PGF_(1α)呈显著负相关。提示脂质过氧化损伤与TXA_2/PGI_2平衡密切相关。认为SOD/LPO、SeGSHPx/LPO,TXB_2/6-keto-PGF_(1α)比值在冠心病诊断中是重要有意义的指标,血小板SOD/LPO比值能更敏感地反映冠心病人氧化与抗氧化能力的平衡状态。     

Alterations of the levels of glycoproteins Ib-IX and IIb-IIIa in platelets stored at 22°C

Platelets stored in CLX™ blood bags, under normal blood banking conditions, were studied for up to 7 days to determine if changes ocurred in the levels of membrane glycoproteins (GP) Ib-IX and IIb-IIIa. Radiolabeled monoclonal antibodies (MAB) were used to estimate the number of glycoprotein molecules on the surface membrane of intact platelets. GP IX and GP IIb-IIIa levels remained essentially unaltered during storage. In contrast, the content of GP Ib at day 7 decreased by 45% of the total when fresh. The aggregation response to ristocetin, which requires GP Ib, was also diminished after 7 days. Addition of protease inhibitors, leupeptin and/or aprotinin did not appear to influence the degradation of this glycoprotein. We conclude that storage at 22°C has deleterious effects on the GP Ib content of platelets.     

Effect of oxygen aeroions on platelet aggregation and lipid peroxidation in health and peritonitis

In patients with peritonitis, the biological effects of oxygen aeroions reflect the interplay between molecular and cellular effects manifesting themselves in the inhibition of lipid peroxidation, increased antioxidizing potential of blood plasma, and decreased aggregating activity of platelets. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 9, pp. 283–285, September, 1997