Fucoidin, but not yeast polyphosphomannan PPME, inhibits leukocyte rolling in venules of the rat mesentery

Leukocyte rolling in venules is inhibited by several sulfated polysaccharides, by antibodies to the leukocyte adhesion receptor L- selectin (LECAM-1), and by recombinant soluble L-selectin. The sulfated fucose polymer fucoidin and the polyphosphomannan PPME bind to L- selectin and inhibit L-selectin-mediated lymphocyte adhesion to lymph node high endothelial venules (LN-HEV). We investigated whether fucoidin and PPME also inhibit leukocyte rolling. Rolling leukocyte flux was determined by intravital microscopy in 47 venules (diameter 21 to 50 microns) of the rat mesentery with and without micro-infusion of each reagent through 8-microns glass micropipettes. Micro-infusion (1 mg/mL) or intravenous (IV) injection (25 mg/kg) of fucoidin, but not vehicle, reduced leukocyte rolling by greater than 90%. The half- effective concentration was approximately 2.5 micrograms/mL. Stroboscopic fluorescence video microscopy showed that fucoidin decreased the fraction of rolling leukocytes from 44% of all leukocytes passing the venules in control to less than 1%. PPME micro-infusion (1 mg/mL) or IV injection (14 mg/kg) did not reduce leukocyte rolling. Hence, leukocyte rolling differs from lymphocyte homing with respect to the effect of PPME. This may be related to fucoidin binding to L- selectin with greater affinity than PPME. Alternatively, inflamed venular endothelium may express a ligand for L-selectin different from that constitutively expressed on LN-HEV.     

高交联聚乙烯与钴铬合金和陶瓷股骨头匹配使用的磨损和蠕变

髋关节骨关节炎患者进行金属对超高分子量聚乙烯(ul tra-high molecular weight polyethylene,UHMWPE)的全髋关节置换是二十世纪最为成功的外科手术之一.据文献报道使用UHMWPE衬垫的骨水泥假体20年成功率达到75%以上[1].     

Unmappable ventricular tachycardia after an old myocardial infarction. Long-term results of substrate modification in patients with an implantable cardioverter defibrillator

Purpose  

The frequent occurrence of ventricular tachycardia can create a serious problem in patients with an implantable cardioverter defibrillator. We assessed the long-term efficacy of catheter-based substrate modification using the voltage mapping technique of infarct-related ventricular tachycardia and recurrent device therapy.     

综合性ICU患者监护记录单临床应用的前瞻性研究

目的研究新时期综合ICU患者的临床监护记录单,以保证患者及护士使用过程的便利及安全。方法将我院ICU自2002年使用的“图标式ICU监护记录单”,在原表格的基础上根据综合ICU患者需要多系统监测的特点进行修订,主要以数字和符号表示形式形成新的护理记录表格,并采取对比的方法考证新旧两种表格的效用。结果两种表格各项指标比较：相同人数的护士分别填写两种不同表格所使用的时间分别是新表格平均（66±11）min,旧表格平均（97±10）min,每份表格的分数设为100分,护理质量检查小组检查的结果,新表格平均（97±2）分,旧表格平均（94±2）分,两组时间及分数比较差异有统计学意义（t=10．6263,4．0307;P〈0．01）;新旧表格使用合格率比较差异有统计学意义（90．12％比82．62％,x2=67．49,P〈0．01）。结论新的监护记录单更科学、更全面、简洁、更适合综合ICU不同种类的患者的记录要求,减轻护士工作量,减少记录时间,提高工作效率。     

替加环素和其他广谱抗菌药物对产丝氨酸碳青霉烯酶和金属β内酰胺酶的肠杆菌科细菌的抗菌活性:SENTRY监测网络的报告

肠杆菌科细菌对碳青霉烯类抗生素的耐药性可以由过量产生AmpC酶且同时外膜孔道蛋白大量缺失和（或）外排泵过量表达,或产生能水解碳青霉烯类的β内酰胺酶引起。这些碳青霉烯酶可以分为金属β内酰胺酶（MSL）和丝氨酸碳青霉烯酶两类。替加环素是一类半合成的甘氨酰环素类抗菌药物,对其他类抗生素耐药的细菌通常对替加环素无交叉耐药。     

TSC1-mTOR-PLK轴以阶段特异性方式调节从施旺细胞增殖到髓鞘形成的内稳态开关

恰如其分的外周髓鞘形成取决于雪旺细胞增殖与分化进程间的平衡。丝氨酸/苏氨酸激酶(mTOR)整合多种环境因素,是细胞生长、代谢、发挥作用的中枢调节者。本文报道了一种mTOR的负性调节剂——结节性硬化复合体(TSC1),通过控制细胞增殖和髓鞘稳态,建立了雪旺细胞谱系进展和髓鞘形成的阶段依赖性程序。小鼠雪旺细胞祖细胞中TSC1的解离导致mTOR信号通路激活,继而导致雪旺细胞过量增殖,分化受阻,髓鞘形成减少。转录组分析显示,TSC1突变体中的mTOR活化使得polo样激酶(PLK)依赖性通路和细胞周期调节剂上调。弱化mTOR或者对PLK进行药理抑制部分挽救了因TSC1缺失导致的外周神经发育过程中的髓鞘形成减少。相较之下,成年小鼠成熟雪旺细胞中TSC1缺失可导致髓鞘的过度增殖和过度生长。本文的发现提示了TSC1-mTOR-PLK信号轴在控制雪旺细胞的发育过程中,从增殖到分化和髓鞘内稳态中起到的阶段特异性功能。