多种血管新生指标在肝细胞肝癌中的表达及敏感性比较

目的　探讨血管新生指标CD34、CD31、vWF、Ⅳ型胶原纤维及层粘连蛋白在肝细胞肝癌(HCC)中的表达及意义 ,同时比较上述几种血管新生因子与增殖细胞核抗原 (PCNA)、病理指标及预后的相关性 ,以便筛选出有效的临床预后指标。方法　采用免疫组化方法 ,对 5 3例肝细胞肝癌的标本进行CD31、CD34、vWF、Ⅳ型胶原纤维及层粘连蛋白的染色、计数 ,并用检测数据与患者的临床资料进行统计分析。结果　统计染色的血管面积后发现 ,CD34与多种临床病理指标无相关性 ;CD31与肝内门静脉浸润相关 ;vWF与肿瘤的TNM分期及肝内门静脉浸润呈正相关 ;CollⅣ与肝内门静脉浸润呈正相关、与术后生存期呈负相关 ;Lam与肝硬化及术中出血量呈负相关、与术后生存期呈正相关。PCNA与肿瘤TNM分期有关。结论　在HCC中 ,CollⅣ、vWF、及CD31为肝细胞肝癌的有效血管新生及预后指标 ;Lam则与肝硬化及术中出血相关 ;PCNA指数肿瘤分期有关 ;CD34不能用作血管新生或预后指标     

Expression of a fibrinogen fusion peptide in Escherichia coli: a model thrombin substrate for structure/function analysis

The initial event in fibrin clot formation is the thrombin-catalyzed cleavage of the A alpha chain of human fibrinogen. Most of the information required for thrombin recognition and cleavage of the A alpha chain lies in the amino terminal 51 residue CNBr fragment. By selective modification of residues in this region, we probed the features that participate in thrombin interactions. We constructed a vector which expressed a tripartite protein (tribrid) consisting of amino acids 1 to 50 of the A alpha chain followed by 60 amino acids of chicken collagen and the beta-galactosidase protein from Escherichia coli. Cell lysates run on NaDodSO4-polyacrylamide gels contained the predicted band of molecular weight (mol wt) 125,000. The tribrid reacted with a monoclonal antibody, Mab-Y18, which recognizes the amino terminus of the A alpha chain. When cell lysates were incubated with thrombin, FPA was released. By including one heterogeneous oligonucleotide in the construction, we generated plasmids that encoded three specific amino acid substitutions. Surprisingly, changing Gly14 to Val did not alter thrombin cleavage, although recognition by Mab-Y18 was lost. Substitution of lie for Arg23 did not alter either thrombin cleavage or monoclonal recognition. Substitution of Leu for Arg 16 altered thrombin cleavage; unexpectedly, recognition by Mab-Y18 was not changed.     

大鼠脂肪间充质干细胞的成骨分化

目的:观察大鼠脂肪间充质干细胞经成骨诱导向成骨细胞分化的生物学特性,探讨其作为骨组织工程种子细胞的可行性。方法:实验于2004-07/2006-03在中南大学湘雅医院中心实验室完成主要工作。①取健康SD大鼠双侧腹股沟区脂肪垫,消化法分离出脂肪间充质干细胞,接种入含有体积分数为0.1的新生牛血清的低糖DMEM培养基进行原代培养。②取第3代的脂肪间充质干细胞,用含有体积分数为0.1的新生牛血清、0.1μmol/L地塞米松、50μmol/L抗坏血酸、10mmol/Lβ-甘油磷酸钠的高糖DMEM培养基诱导其向成骨细胞分化。③于3,5,7,10,12,14,21d分别采用倒置显微镜观察细胞形态及增殖情况、Gomori改良钙钴法碱性磷酸酶染色、茜素红S钙结节染色和Ⅰ型胶原免疫细胞化学染色检测脂肪间充质干细胞成骨分化的情况。结果:①脂肪间充质干细胞原代细胞呈成纤维细胞样长梭形外观,传代稳定,细胞形态均一。②经成骨诱导,脂肪间充质干细胞体积增大,呈多角形;成骨诱导14d,Gomori改良钙钴法碱性磷酸酶染色,细胞胞浆内可见浅棕色至棕黑色的颗粒,平均染色阳性率为80%;碱性磷酸酶活性随时间的延长而逐渐增高[3,5,7,10,12,14d依次为(2.43±0.09),(3.60±0.08),(5.01±0.09),(7.75±0.07),(9.59±0.09),(10.94±0.10)μkat/L];成骨诱导21d,钙结节形成明显,茜素红S染色,呈红色结节;成骨诱导7d,Ⅰ型胶原免疫细胞化学染色,细胞胞浆呈棕黄色,胞核经苏木精复染为蓝色。结论:大鼠脂肪间充质干细胞经成骨诱导具有成骨细胞的生物学特性,可作为骨组织工程的种子细胞。     

Survey on pretransfusion testing

BACKGROUND: Hospitals and blood centers throughout the United States use a variety of reagents and methods to perform pretransfusion testing. A survey was developed to determine the reagents and methods in use and their relative prevalence in different work settings. STUDY DESIGN AND METHODS: A national survey on pretransfusion testing was conducted. Surveys were distributed to state and regional blood bank associations, which then distributed them to hospitals and blood centers within their region. In most instances, the blood centers distributed the survey to the local hospitals. Completed surveys were returned to the authors for review, and all information was entered into a database for analysis. RESULTS: Analysis of the data shows that the majority of blood banks use monoclonal reagents for ABO testing and monoclonal-polyclonal blended reagents for Rh testing. The data show that anti-IgG and polyclonal antihuman globulin reagents are used almost equally for antibody screening (detection) tests and that most blood banks use a three-cell antibody-screening test. Slightly more than 50 percent of hospitals use an immediate-spin crossmatch in the absence of unexpected antibodies. CONCLUSION: A number of approved reagents and methods are used by blood bank laboratories for pretransfusion testing. Facility size (number of beds) and type tend to influence the choice of methods and reagents employed. This survey provides an opportunity for blood bank laboratories to compare their current practices with those of their peers.