血栓前体蛋白与心脏瓣膜置换术后的抗凝监测

目的：探讨血栓前体蛋白(TPP)在心脏机械瓣膜置换术后抗凝治疗监测中的意义，及制定术后抗凝治疗的合理方案。方法：比较抗凝组(60例)和对照组(20例)的国际标准化比率(INR)、TPP，并比较抗凝组中有、无房颤的病人华法林用量、INR和TPP，对抗凝组病人TPP和INR的关系作一元线性回归分析，比较各组的INR和血浆TPP浓度。结果：抗凝组与对照组相比，TPP低、INR高。抗凝组有房颤者的血浆TPP浓度高于窦性心律者。线性回归分析结果表明，TPP和INR无明显相关性。出血病人的血浆TPP浓度明显低于正常高限(6μg／ml)。结论：TPP是心脏机械瓣置换术后抗凝治疗理想的辅助监测指标。术后有房颤心律者的血栓栓塞危险性增加。抗凝治疗应同时检测INR和TPP。     

衰老红细胞与带3蛋白

循环系统里的成熟红细胞在其生命过程里经历着氧化性衰老，相应细胞组份出现血红蛋白变性、膜蛋白交联、带3蛋白聚集以及带3蛋白降解等多种修饰。这些修饰作为红细胞膜上的衰老信号参与构成衰老细胞抗原，由此启动与IgG自身抗体(主要为带3蛋白抗体)的结合以及补体的沉淀，最终是免疫吞噬系统对异常细胞的识别清除．现就衰老红细胞与带3蛋白的关系作一综述。     

Association of a 70-kDa tyrosine phosphoprotein with the CD16:ζ:γ complex expressed in human natural killer cells

The CD16: ζ: γ receptor complex allows natural killer (NK) cells to recognize and eliminate antibody-coated target cells. Whereas the ectodomain of CD16 is the receptor for Fcγ domains of immunoglobulins, disulfide-linked homo- and heterodimers composed of ζ and γ are required for the cell surface expression, and signal transduction properties of the complex. Engagement of CD16 activates the tyrosine kinase pathway, which induces the tyrosine phosphorylation of several substrates, including the ζ subunit and the phospholipase C γ-1 and γ-2 isoforms. Here we show that CD 16 stimulation of either peripheral blood NK cells, leukemic NK cells, or Jurkat transformants expressing a CD16:ζ:γ receptor complex, results in the tyrosine phosphorylation of a 70 kDa ζ-associated protein (pp70). Similarly, a 70-kDa ζ-associated phosphoprotein in T cells has been shown to be a tyrosine kinase (ZAP-70). Peptide mapping analysis indicates that the 70-kDa ζ-associated phosphoproteins from T cells and NK cells are structurally indistinguishable. We conclude that the CD16:ζ:γ complex may use a ZAP-70-related non-receptor tyrosine kinase, in the CD16 signaling cascade leading to NK cell activation.     

Protein kinase C in focal ischemic rat brain: dual autoradiographic analysis of [C]iodoantipyrine (IAP) and [H]phorbol-12,13-dibutyrate (PDBu)

Protein kinase C (PKC) activity was measured in rat brain with 2 h of middle cerebral artery (MCA) and common carotid artery (CCA) occlusion, using dual autoradiography of [¹⁴C]iodoantipyrine (IAP) and [³H]phorbol-12,13-dibutyrate (PDBu). In the ischemic brain, it required more than 120 min of incubation to obtain a plateau in PDBu binding. In contrast, the binding of PDBu in non-ischemic brain reached a plateau with incubation for 60 min. This delay of PDBu binding in the ischemic brain suggests that the affinity of this ligand is reduced due to a change in structure of the cell membrane caused by ischemia. PDBu binding in the ischemic brain increased significantly compared to the non-ischemic brain. This finding provides further evidence that excessive activation of PKC in the ischemic brain may play an important role in ischemic neuronal damage. ©1997 Elsevier Science B.V. All rights reserved.     

Protein kinase C agonist and antagonist effects in normal human epidermal keratinocytes

Abstract Several lines of evidence implicate protein kinase C (PKC) in the development of basal cell and squamous cell carcinomas, tumors which originate from epidermal keratinocytes. To examine PKC in a model relevant to human skin, we exposed normal human epidermal keratinocytes (NHEK) in serum-free media to a variety of PKC agonists and antagonists. NHEK PKC activity increased up to 10-fold within the 1st hour of exposure to tetradecanoyl phorbol acetate (TPA), and gradually returned to control values within 72 h. TPA-induced PKC activity was enhanced by pretreatment of cultures with protein and RNA synthesis inhibitors. TPA-induced growth arrest and differentiation was antagonized by staurosporine. Down-regulation by bryostatin pretreatment blocked TPA-stimulated differentiation. Our overall conclusion is that activation of PKC in cultured human keratinocytes is required for differentiation. These results are crucial to the analysis of compounds suspected of promoting or inhibiting epidermal tumors.     

Effects of phorbol ester on carbachol-induced contraction in bovine ciliary muscle: possible involvement of protein kinase C

The aim of the research was to characterize muscarinic receptors of bovine ciliary muscle and to investigate the desensitization process. The role of protein kinase C was analyzed. The results show that muscarinic receptors of bovine ciliary muscle have the pharmacological characteristics of the M₃ subtype. Acute exposure to phorbol esters (1 μM phorbol 12,13-dibutyrate, PDB, or 0.1 μM phorbol 12-myristate 13-acetate, PMA, for 15 and 5 min, respectively) resulted in antagonism of muscarinic receptor-mediated contraction. Long-term pretreatment (18 h) with PMA to down-regulate protein kinase C resulted in potentiation of carbachol-induced contraction, reduction of agonist-induced desensitization and loss of phorbol ester-induced desensitization. Staurosporine (3 μM) and H₇ [1-(5-isoquinolinesulfonyl)-2-methyl-piperazine] (1 μM), protein kinase C inhibitors, produced a significant potentiation of the contractile effect of carbachol, reduced the desensitization produced by repeated addition of carbachol and suppressed that induced by phorbol esters. In vitro incubation with carbachol, PDB or PMA did not cause any modification of the binding of labeled [³H]quinuclidinyl benzilate. In vitro incubation with PDB and PMA produced, as expected, a significant translocation of protein kinase C from the cytosol to the membrane. The incubation of the ciliary muscle with carbachol, using the protocol of exposure that induced maximal desensitization of contractile responses, produced a significant redistribution of the enzyme from the cytosol to the membrane. These findings suggest that agonist-induced modulation of functional cholinergic sensitivity in ciliary muscle is correlated, at least partially, to the translocation of protein kinase C from the cytosol to the membrane. The desensitization by phorbol esters is completely due to protein kinase C activation; during the desensitization process, direct modification of the density and affinity of muscarinic receptors is not involved.     

他汀类药物早期干预对急性冠脉综合征患者血脂、高敏C反应蛋白和纤维蛋白原的影响

目的 比较他汀类药物和阿司匹林联合用药与单用阿司匹林对急性冠脉综合征患者血脂、高敏C反应蛋白及纤维蛋白原的影响。方法 所有患者均在急性冠脉综合征发病后72h内开始接受药物治疗，他汀组(40例)应用他汀类药物加阿司匹林治疗8周，对照组(16例)单用阿司匹林治疗，观察两组总胆固醇、低密度脂蛋白胆固醇、高敏C反应蛋白和纤维蛋白原水平的变化。结果 治疗8周后，他汀组各指标显著降低，面对照组仅高敏C反应蛋白水平显著下降。他汀类药物降低高敏C反应蛋白、纤维蛋白原的程度与其降脂作用无关。结论 他汀类药物与阿司匹林联合用药降低高敏C反应蛋白和纤维蛋白原的作用可能优于单用阿司匹林，并与其抗炎作用有关。     

高压氧对家兔面神经撞击伤后面神经核内生长相关蛋白变化的影响(论著)

目的：研究面神经撞击伤后面神经核内生长相关蛋白（ＧＡＰ－４３）的变化及高压氧（ＨＢＯ）治疗的影响。方法：利用ＢＩＭ－Ⅱ型生物撞击机致家兔右侧面神经干损伤，应用ＳＰ免疫组化染色法观察损伤后１、３、７、１４和２１天（分别用ＨＢＯ治疗及不用ＨＢＯ为对照）面神经核内ＧＡＰ－４３的变化，并用电镜观察面神经干超微结构变化。结果：面神经损伤第１天，伤侧面神经核区ＧＡＰ－４３样免疫反应性神经元（ＧＬＩＮ）开始增多，第１４天其增多达到高峰，第２１天逐渐下降。ＨＢＯ治疗组伤后不同时期ＧＬＩＮ的增多明显高于对照组。伤后第２１天，与对照组相比ＨＢＯ组面神经干电镜观察可见较多的新生髓鞘。结论：ＨＢＯ治疗可使伤后面神经核内ＧＬＩＮ增多，因而有助于面神经损伤后的修复与再生。     

Extraction of Serum Proteins Adsorbed on the Surface of Dialysis Membranes

Abstract: Extraction of adsorbed proteins from dialysis membranes that had been used during actual hemodialysis procedures was performed. The condition of extraction with SDS plus 2–mercaptoethanol at 95°C is more efficient than with only PBS or with SDS solution without 2–mercaptoethanol at 37°C.     

构建玻片蛋白质芯片的实验研究

目的:探讨玻片蛋白质芯片的构建方法及其中间操作条件的选择与优化。方法:利用生物芯片点样仪将超微量蛋白质点到经特殊处理的玻璃片表面,然后选用不同的化学试剂对玻片背景进行封闭;再用荧光素标记的蛋白质与点样蛋白杂交;最后用生物芯片分析仪扫描成像并进行分析,比较不同条件下芯片的显示效果。结果:蛋白质样品与片基稳定结合,并保持原活性状态;封闭试剂选用酪蛋白或明胶效果较佳;点样探针与其特异蛋白质抗体可稳定结合,结合效果与点样蛋白浓度在一定范围内呈正相关;在1.6 cm×1.6 cm的玻璃片面积上,构建了36×36=1269点的蛋白质芯片。结论:本实验条件下,蛋白质抗原或抗体可以稳定地固定于经过处理的玻璃片表面.制成免疫型蛋白芯片,并可通过随后的抗原抗体反应与荧光素标记的相应抗体或抗原结合,用生物芯片分析仪可对其荧光信号进行检测分析。