正常人血小板介电谱的实验研究

在100KHz～110MHz范围内,测量人血小板的介电谱,分析了人血小板对交流电场的介电响应的数据特征。利用频域阻抗技术首次测量了正常人血小板交流阻抗,绘制血小板的介电常数和电导率与电场频率的关系曲线。建立了人血小板的介电谱和Cole-Cole图,明确了人血小板的介电频响的数据特征。在射频电场中,人血小板的介电常数和电导率具有频率依赖性,血小板介电谱具有两个特征频率:第一特征频率fC1为6.66MHz,第二特征频率fC2为9.81MHz。     

新生儿高间接胆红素血症患儿凝血象的研究及临床意义

目的　探讨凝血因子、血小板和新生儿高间接胆红素血症的关系 ;方法　用散射比浊法测定新生儿高间接胆红素血症患儿 6 0例和正常足月新生儿 2 0例的凝血酶原时间 (PT)、激活的部分凝血活酶时间 (APTT) ,同时检查血小板计数和肝功能 ;结果　新生儿高间接胆红素血症患儿的PT、APTT比正常足月新生儿组明显升高 ,有显著性差异 ,P值均 <0 .0 5 ,而血小板计数和肝功能两组间比较 ,无显著性差异 ,P值 >0 .0 5 ;结论　新生儿高间接胆红素血症患儿临床上常出现脐部渗血、穿刺部位出血不止等表现与新生儿血小板数量无关 ,而与PT、APTT延长有关 ,可能由于母乳喂养的推广和生后没有进行常规维生素K预防。因此 ,我们建议在治疗新生儿高胆红素血症的同时 ,要注意预防维生素K的缺乏。     

血小板、基质金属蛋白酶与肿瘤转移

血小板除参与正常的止血过程外还具有很多病理和生理作用。血小板活化后可以分泌基质金属蛋白酶(matrix metalloproteinases,MMPs)。MMPs属于Zn2 和Ca2 依赖的内肽酶家族,能特异性与细胞外基质成分相结合并降解细胞外基质。MMPs降解基底膜中的主要成分Ⅳ型胶原,是肿瘤转移发生必不可少的关键步骤。血小板能够与肿瘤细胞结合并促进肿瘤转移,而MMPs在血小板促进肿瘤转移过程中发挥了重要的作用。     

低氧致鼠腺泡内肺动脉PDGF—B链蛋白表达的变化

目的：探讨血小板源性生长因子（ＰＤＧＦ）在低氧肺动脉高压血管构形重建发生中的作用。方法：应用免疫组化技术结合计算机图像分析，检测了低氧大鼠腺泡内肺动脉（ＩＡＰＡ）ＰＤＧＦ－Ｂ链蛋白表达水平。结果：常氧时，ＩＡＰＡ仅有ＰＤＧＦ－Ｂ链蛋白弱表达；低氧１天时，ＩＡＰＡ便有较强的ＰＤＧＦ－Ｂ链蛋白表达，定位于ＩＡＰＡ的内皮和中膜，低氧３天至１４天仅分布于中膜；低氧１、３、５、７、１４天各时间点ＰＤＧＦ－Ｂ链蛋白表达分别为常氧组的１．５３、１．５９、１．５６、１．６２和１．４２倍，差异有显著性（Ｐ＜０．０１）。结论：ＰＤＧＦ－Ｂ链蛋白可能参与了低氧肺动脉高压血管构形重建的发病过程     

IL-10 stimulates production of platelet-activating factor by monocytes of patients with active systemic lupus erythematosus (SLE)

IL-10 displays modulatory properties on the synthesis of platelet-activating factor (PAF), a potent inflammatory mediator of vascular injury. Despite the fact that IL-10 is considered to be an anti-inflammatory cytokine, IL-10 levels correlate with disease activity in SLE. Moreover, in SLE IL-10 is unable to exert its immunosuppressive and anti-inflammatory effects. We have investigated the ability of IL-10 to stimulate PAF production from monocytes of SLE patients. Spontaneous and IL-10-stimulated PAF production by peripheral blood monocytes was measured in active (n = 13) and inactive (n = 14) SLE patients and in 15 normal control subjects. We observed that monocytes derived from patients with active SLE, but not from controls or inactive SLE, spontaneously produced significant amounts of PAF. Moreover, IL-10 enhanced the synthesis of PAF from monocytes of active SLE patients only. IL-10-induced PAF production correlated with the severity of the disease and with the extent of proteinuria. These results indicate that IL-10 only stimulates the synthesis of PAF from monocytes of SLE patients when immunologically active, suggesting that IL-10 may possess a paradoxical proinflammatory effect in SLE by promoting the production of PAF, a secondary mediator of inflammation.     

Glomerulosclerosis develops in Thy-1 nephritis under persistent accumulation of macrophages

To clarify the relationship between macrophages and development of glomerulosclerosis, the authors developed a new experimental nephritis model with macrophages persisting in Thy-1 nephritis. Methyl-cellulose was administered intraperitoneally in addition to the intravenous injection of the anti-Thy-1 antibody to Wistar rats. Foamy macrophages influxed into the lytic mesangium and stayed to form nodular aggregates. Mesangial cells proliferated with the formation of extracellular matrices around these nodular aggregates of macrophages. Immunohistochemical analyses revealed that alpha-smooth muscle actin (alpha-SMA) was expressed in the proliferative area around these nodules of foamy macrophages from day 7. Type I collagen and type IV collagen were also expressed around the foamy macrophages in correspondence with alpha-SMA expression from day 7. The electron microscopic study revealed that collagen fibrils were formed around the transformed mesangial cells. The expression of platelet endothelial cell adhesion molecule-1 (PECAM-1, CD31), a marker of glomerular vasculature endothelial cells, was not found in the area occupied by the foamy macrophages, suggesting the impairment of glomerular reconstruction. Macrophages may participate in the progression of glomerulosclerosis in Thy-1 nephritis by enhancing the production of the extracellular matrix through transformed mesangial cells and preventing reconstruction of the capillary network.     

New Method for DNA Microarrays Development: Applied to Human Platelet Antigens Polymorphisms

DNA microarrays are a powerful experimental tool for the detection of specific genomic sequences and are invaluable to a broad array of applications: clinical diagnosis, personalized medicine, drug research and development, gene therapy, food control technologies, and environmental sciences. Alloimmunization to human platelet antigens (HPAs) is commonly responsible for neonatal alloimmune thrombocytopenia, post-transfusional purpura and platelet transfusion refractoriness. Using DNA microarrays, we developed a diagnosis to type the biallelic HPA-1 platelet group. The region for the human genomic DNA sequence that contains the polymorphism responsible for HPA-1 alleles was amplified by polymerase chain reaction (PCR). The expected DNA fragments were hybridized on DNA microarrays, and the data were analyzed using specially developed software. Our initial results show that the two HPA-1 antigens polymorphisms containing a single base difference were detected using DNA microarrays.     

孕妇妊娠晚期和妊高征患者血小板参数的分析

目的观察正常孕妇妊娠晚期和妊高征患者血小板参数的变化及临床意义。方法采用日本Sysmex KX-21型血液细胞分析仪分别对正常孕妇（118例）、妊高征患者（59例）及对照组（正常婚检妇女59例）的血液标本进行血小板（PLT）计数、平均血小板体积（MPV）、血小板分布宽度（PDW）的测定。结果妊高征组和正常孕妇组的MPV、PDW显著高于对照组（P〈0.01）;妊高征组MPV、PDW明显高于正常孕妇组（P〈0.05）;妊高征组的PLT显著低于对照组（P〈0.01）。结论妊高征患者由于血小板消耗和破坏增加,导致血小板减少,MPV、PDW明显增高,因此,检测血小板参数对预测妊高征的发生有一定的参考意义。     

MPC-BMA共聚物的合成及其血小板粘附行为研究

本研究首先合成了含有磷酸胆碱基团的单体2-甲基丙烯酰氧乙基-2′-三甲胺乙基磷酸酯.内盐(MPC)和甲基丙烯酸正丁酯(BMA)的共聚物,采用红外光谱对其主要基团进行了表征分析,利用血小板粘附实验研究了磷脂聚合物膜的血小板粘附性,通过扫描电镜对血小板在聚合物膜上的形态和粘附量进行观察。结果表明:MPC含量越高,血小板的粘附量和变形程度越小;与其它亲水性单体如HEMA、HPOEM360、HPOEM526相比,等量MPC更能有效的降低其聚合物膜的血小板粘附性。