荷载角质细胞生长因子纳米微囊脱细胞真皮的制备、特性及其对表皮干细胞群生长的作用

目的:构建一种荷载有角质细胞生长因子且能控制释放的新型组织工程化皮肤。方法:实验于2006-03/12于中山大学附属第二医院干细胞研究中心及中山大学高分子研究所进行。①材料:角质细胞生长因子(CytolLAB公司),牛血清白蛋白(Amresco公司),聚乳酸-羟基乙酸共聚物(由中山大学高分子化学研究所合成,聚乳酸与聚羟基乙酸摩尔比为75∶25,相对分子质量为50000),脱细胞真皮(北京桀亚莱福生物技术有限公司)。②方法:采用超声乳化-溶剂挥发及低温干燥方法,将角质细胞生长因子以牛血清白蛋白作联接包裹在聚乳酸-羟基乙酸共聚物内制成纳米微囊,根据公式计算微囊成球率、载药量及包封率;将微囊溶解于二氯甲烷中,进行体外释放实验检测不同时间牛血清白蛋白吸光度,作出牛血清白蛋白释放曲线;将角质细胞生长因子纳米微囊交联于脱细胞真皮表面,制成荷载角质细胞生长因子纳米微囊脱细胞真皮(KGF-ADM),在扫描电镜下观察微囊形态、分布及其与脱细胞真皮连接情况;采用Ⅰ型胶原酶复合胰蛋白酶消化的方法,从门诊健康患者无菌手术切除的包皮组织中获取表皮细胞单细胞悬液,经免疫荧光检测,证实其中含表皮干细胞,将表皮干细胞群分别接种于KGF-ADM及聚乳酸-羟基乙酸共聚物上,于恒温箱中培养3d后,在扫描电镜下观察细胞形态、生长情况及其与材料连接情况。结果:①纳米微囊成球率为85%,载药量为17.3%,包封率为73.5%。②纳米微囊中牛血清白蛋白可以控制缓慢释放,其释放曲线显示初期释放速度较快(前5d累计释放约40%),后进入缓慢释放期(30d累计释放约75%)。③扫描电镜检测显示纳米微囊形态规则,在KGF-ADM表面分布均匀,与KGF-ADM联接良好,部分分布于KGF-ADM深面;表皮干细胞群在KGF-ADM上生长活跃,细胞形态良好,部分形成克隆。结论:采用该方法可成功构建荷载角质细胞生长因子纳米微囊的新型组织工程化皮肤。     

The binding of human alloantibodies to recombinant glycophorin A

Chinese hamster ovary (CHO) cells were transfected with the wild-type, M allele of glycophorin A cDNA. The binding of human alloantibodies to recombinant glycophorin A was assessed with a modified hemagglutination-inhibition assay. Patient sera were incubated with acetone powders derived from CHO cells, and the adsorbed supernatants were tested in standard hemagglutination assays. Five M antibodies and one sample containing anti-En(a) bound to transfected CHO cells expressing glycophorin A but did not bind to untransfected CHO cells. Three N antibodies as well as 21 other alloantibodies (representing other major red cell blood group specificities) bound to neither CHO cell line. The M allele specificity of recombinant glycophorin A was further verified by the demonstration that a high-titer D alloantibody maintained the same titer of agglutination after incubation with recombinant glycophorin A. Transfected CHO cells thus express an M blood group antigen that appears to be serologically equivalent to that found on human red cells. A panel of cell lines expressing mutant glycophorin A molecules with defined variations in amino acid sequence and carbohydrate composition will be useful in studies of the fine specificity of human glycophorin alloantibodies. This approach may also provide an abundant source of artificial antigens for clinical use in blood group serology.     

三种缝合材料对兔气管吻合口愈合质量的影响

目的:采用动物实验观察临床常用的3种缝合材料对气管端端吻合术后组织反应、愈合质量的影响。方法:实验于2005-09/2006-10在南华大学动物实验部将36只新西兰大白兔随机分为3组,分别选用丝线、涤纶线、人工合成吸收缝线进行气管切开后端端吻合。于术后1,2,4周分别取吻合口处气管,计算出吻合口内径占术前气管内径的百分率,反映气管的通畅程度;组织切片病理学观察炎症细胞浸润程度;免疫组织化学SABC法测定转化生长因子β1阳性面积比。结果:①肉眼观察显示:术后1,2周3组吻合口愈合没有显著差别,术后4周丝线组、涤纶线组均有缝线残留形成肉芽肿,人工合成吸收缝线组缝线基本吸收。②吻合口内径通畅率:术后1周、2周3组无显著差别(P>0.05),术后4周人工合成吸收缝线组高于其他2组(P<0.05)。③炎症细胞浸润程度:术后1,2周3组间比较无显著差别(P>0.05);术后4周人工合成吸收缝线组低于其他2组(P<0.05)。④转化生长因子β1阳性面积比:术后1,2周3组间比较无显著差别(P>0.05);术后4周人工合成吸收缝线组低于其他2组(P<0.05)。结论:兔气管切开后行端端吻合术,采用人工合成吸收缝线组织相容性好,炎症反应低,有利于吻合口的愈合。     

大连市7～18岁学生1995～2005年肥胖流行情况分析:以皮褶厚度计算体脂含量

目的:采用皮褶厚度计算体脂含量的方法,了解大连学生超重和肥胖流行现状和流行趋势,为青少年生长发育研究、改善学生营养状况和制定学生肥胖防治措施提供依据。方法:①2005-05/06采用简单随机抽样原则,抽取大连市区的出生并生长的7～18岁汉族学生2474名,其中男生1244名,女生1230名。采用国际通用的人体测量学方法测量纳入学生的肱三头肌和肩胛下角部的皮褶厚度,并通过皮褶厚度推算体密度,计算全身体脂含量,再利用体脂含量判断肥胖并计算发生率。并将上述结果与1995年大连市内7～17岁汉族学生1190名和2000年大连市内7～18岁汉族学生1275名肥胖调查结果进行对比分析。②性别差异比较使用大样本的u检验。结果:2005年参与调查的2474名学生均进入结果分析。①学生体脂含量女生随年龄的增长而增加,男生则在11岁时达高峰后呈逐渐下降趋势,生长曲线男女无交叉现象。而且相同年龄段的体脂含量均是女生高于男生,并且除10～13岁年龄组外,其他年龄组差异均有显著性意义(u>1.96,2.58,P<0.05～0.01)。②与1995年调查结果比较,学生体脂含量10年来有较大程度增长,10年平均增长男女生分别为6.31%和4.47%。③学生2000年超重、轻度肥胖和中重度肥胖的发生率男生分别为14.3%,11.1%和7.9%,女生分别为11.0%,7.2%和2.8%。2005年超重、轻度肥胖和中重度肥胖的发生率男生分别为18.0%、11.6%和19.9%,女生分别为15.0%,10.2%和11.7%。结论:①2005年青春期后学生体脂含量有性别差异。②大连学生10年来体脂含量有较大程度的增长,并有继续增加的趋势。③大连学生5年间超重、轻度肥胖和中重度肥胖的发生率增加明显。     

Allogeneic blood transfusion-induced enhancement of tumor growth: two animal models showing amelioration by leukodepletion and passive transfer using spleen cells [see comments]

Allogeneic blood transfusions have been reported to induce immunomodulation in recipients of blood products. While the mechanism(s) of this immunomodulatory effect is unknown, it has been suggested that this effect of allogeneic blood transfusions could adversely affect patients with a malignant disorder. These concerns have been supported by a number of nonrandomized, mainly retrospective, clinical studies which indicate that allogeneic blood transfusions can adversely affect prognosis following the surgical treatment of oncology patients. Recently, we have shown that allogeneic blood transfusions enhance primary tumor growth and increase metastatic pulmonary nodule formation in inbred mice. The tumor growth-promoting activity of allogeneic blood transfusions was studied also using outbred rabbits. In this present study, we demonstrate that the tumor growth-promoting effect of allogeneic blood transfusions is mediated by donor leukocytes and that this effect can be abolished by their removal before transfusion. We show also that the allogeneic blood transfusion tumor growth-promoting effect can be passively transferred to naive animals (both mice and rabbits) using spleen cells from allogeneically transfused animals. In these experiments, numbers of metastatic pulmonary nodules were significantly increased in both mice and rabbits that had received spleen cells from allogeneically transfused animals compared with those that had received spleen cells from syngeneically transfused animals, or from animals that had been transfused with leukodepleted allogeneic blood.     

犬骨髓基质干细胞与异种骨复合修复自体尺骨缺损

目的:观察骨髓基质干细胞与异种脱蛋白松质骨复合修复尺骨缺损的可行性。方法:实验于2006-01在辽宁医学院附属第一医院外科实验室(省级重点实验室)完成。①实验材料:取12月龄健康杂种犬18只,体质量(15.0±2.2)kg。②实验方法:将所有动物的双侧尺骨制备成中断20mm骨-骨膜缺损模型,骨髓基质干细胞与脱蛋白松质骨于体外复合培养后,将其植入其中16只犬的右侧缺损处作为实验组,左侧植入单纯脱蛋白松质骨作为对照组,另2只犬不植入任何材料为空白组。③实验评估:在4,8,12周分别行大体标本、扫描电镜和组织学观察,比较3组骨缺损修复的能力。结果:纳入健康杂种犬18只,均进入结果分析。4周时实验组支架材料部分吸收,植入物表面有纤维骨痂形成,对照组支架材料少量吸收,植入物表面有少量骨样组织形成;8周时,大体标本及组织学观察,实验组中的支架材料已完全降解,骨缺损部分修复,对照组中植入物两端少量新骨形成,材料中为纤维骨样组织;12周时,实验组骨缺损完全修复,对照组植入物两端有新骨包绕,与骨端连接紧密。12周时空白组骨缺损未修复。结论:利用体外扩增培养的骨髓基质干细胞与异种骨组合,具有较强的骨传导和骨诱导活性。     

Prognostic and aetiological factors in chronic thromboembolic pulmonary hypertension

Several prognostic variables have previously been identified in patients with chronic thromboembolic pulmonary hypertension (CTEPH). Specific medical conditions have also been associated with the development and prognosis of CTEPH. Using a national registry, the current authors have assessed the prognostic value of a larger number of variables and have also attempted to validate the clinical importance of previously identified aetiological factors. Baseline information for all 469 CTEPH patients diagnosed in the UK pulmonary hypertension service between January 2001 and June 2006 was collected from hospital records. Although univariate analysis confirmed the prognostic importance of pulmonary resistance, in multivariate analysis gas transfer and exercise capacity predicted pulmonary endarterectomy perioperative mortality. Cardiac index and exercise capacity independently predicted outcome in patients with nonoperable disease. Previous splenectomy was noted in 6.7% of patients, being significantly more common in patients with nonoperable than operable disease (13.7 versus 3.6%). Medical risk factors were not found to predict mortality. In a large national cohort, predictors of outcome in patients with both operable and nonoperable chronic thromboembolic pulmonary hypertension have been identified. These may be useful in planning treatment. The aetiological importance of previously identified medical risk factors has been confirmed, although the current authors were unable to validate their prognostic strength.