Heat-shock protein 60 translocates to the surface of apoptotic cells and differentiated megakaryocytes and stimulates phagocytosis

Heat-shock protein 60 (Hsp60) is a highly conserved stress protein which has chaperone functions in prokaryotes and mammalian cells. Hsp60 is associated with the mitochondria and the plasma membrane through phosphorylation by protein kinase A, and is incorporated into lipid membranes as a protein-folding chaperone. Its diverse intracellular chaperone functions include the secretion of proteins where it maintains the conformation of precursors and facilitates their translocation through the plasma membrane. We report here that Hsp60 is concentrated in apoptotic membrane blebs and translocates to the surface of cells undergoing apoptosis. Hsp60 is also enriched in platelets derived from terminally differentiated megakaryocytes and expressed at the surface of senescent platelets. Furthermore, the exposure of monocytic U937 cells to Hsp60 enhanced their phagocytic activity. Our results suggests that externalized Hsp60 in apoptotic cells and senescent platelets influences events subsequent to apoptosis, such as the clearance of apoptotic cells by phagocytes.     

Pancreatic islet β-cell deficit and glucose intolerance in rats with uninephrectomy

This study was performed to examine the effect of chronic renal impairment and renin-angiotensin system (RAS) activation induced by unilateral nephrectomy (UNX) on the development of pancreatic islet β-cell deficit and glucose intolerance. Sprague-Dawley rats were randomized into three groups: untreated UNX (n = 10), UNX treated with the angiotensin-converting enzyme inhibitor lisinopril (n = 8) and sham operation (n = 10). Blood glucose, serum insulin, renal function and histological changes of kidney and pancreas were examined 8 months postoperation. Compared with the sham rats, UNX rats developed renal impairment, insulin deficiency and glucose intolerance. Histological staining revealed an islet β-cell deficit associated with increased immunoreactivity for angiotensin and angiotensin type 1 receptor in UNX rats. Treatment with lisinopril significantly improved renal dysfunction, hyperglycemia, insulin secretion and islet RAS expression. These data suggest that chronic renal impairment and RAS activation may contribute to islet β-cell loss and glucose intolerance. RAS blockade may therefore prevent these disorders. Received 29 August 2007; received after revision 25 September 2007; accepted 27 September 2007     

残障学生健康心理之养成

分析了残障学生特殊心理问题的形成及心理健康问题的原因, 并根据其分类的不同分析了肢残生挥之不去的自卑及对人生的茫然与朦胧; 指明了解决残障生心理健康问题的途径和方法。途径是一般性补偿和科学补偿。方法是教育心理学方法和特别研究设置的补偿方法, 还提出了因人施教、递进式教育方法及实施新科技教学方法。     

考虑变厚度的杂交应力元

提出了用于变厚度板平面应力问题分析的杂交元列式,其中以位移场和膜力场为独立未知场量.基于Pian-Sumihara四边形杂交单元的五参数应力场和常规双线性位移场构造一个变厚度平面四边形杂交元.通过若干数值算例验证了新单元的正确性和优越性.     

PCR芯片控温系统研究

通过采用以单片机为核心的数字电路控温技术、PWM技术以及PID控温算法,研制出成本低、控温精度高、能用于DNA扩增的PCR芯片温度控制系统。     

低碱度钢渣基油井及地热井胶凝材料的研究--Ⅲ富镁低碱度钢渣的水热反应

通过研究富镁低碱度钢渣的水热反应得出富镁低碱度钢渣具有水热活性,水热条件下形成具有胶凝性的富镁水化硅酸钙产物.钢渣中CMS、C3MS2的水热活性高于纯CMS、C3MS2的水热活性.Mg2+优先固溶于水化硅酸钙中,其余部分根据水热温度不同而形成Mg(OH)2或蛇纹石.     

NH_3·(H_2O)体系中氢键的理论计算

用量子化学密度泛函理论方法研究了NH3·(H2 O)体系中氢键特征 ,计算了不同基组条件下NH3·(H2 O)体系中氢键的键长 ,同时在Gaussian 3 (G3 )水平上计算了NH3·(H2 O)体系中氢键的键能和成键特征 ,得到NH3·(H2 O)体系中生成氢键有两种构象 .     

新型二取代茚满酮二苯并-24-冠-8的合成

以多聚磷酸（PPA）为催化剂和反应溶剂,丙烯酸为酰化剂,对二苯并－24－冠－8进行酰化,成功地合成了双茚满酮型二苯并－24－冠－8,产物由IR,MS和元素分析鉴定了其结构。     

双氯乙酰基二苯并—18—冠—6的合成

以多聚磷酸（PPA）为催化剂和反应溶剂,氯乙酸为酰化剂,对二苯并－18－冠－6进行酰化,成功地合成了双氯乙酰取代二苯并－18－冠－6,产物由IR,MS和元素分析鉴定了其结构。     

地震工程中的Conventional Pushover和Adaptive Pushover分析法

阐述了Conventional Pushover分析法的基本原理和方法,指出固定侧向力加栽模式的缺陷：由于Adaptive Pushover分析法考虑了结构刚度退化、高阶振型的影响、地震反应谱理论以及SRSS或CQC振型组合的综合作用,同固定侧向力加栽模式相比,对结构受力状态的模拟更加准确。指出Pushover分析法尚存在的问题。