Use of the intra-aortic balloon pump for dilatation of benign tracheobronchial strictures

Tracheobronchial benign stenoses may cause life-threatening emergencies. Here, we will describe a novel technique for the management of tracheal and bronchial stenoses using an intra-aortic balloon pump. The intra-aortic balloon pump was used for dilatation of a postoperative tracheal stricture in a 43-year-old man and a bronchial stricture in a 29-year-old woman with Wegener's granulematosis. There were no intraoperative or postoperative complications in either patient, and the stenosis was relieved successfully in each patient. The intra-aortic balloon pump can be used safely and effectively for the management of difficult tracheobronchial strictures.     

Treatment of respiratory failure in an infant with bronchopulmonary dysplasia infected with respiratory syncytial virus using inhaled nitric oxide and high frequency ventilation

A 2-month-old, former 28-week premature infant with brochopulmonary dysplasia infected with respiratory syncytial virus was treated with nitric oxide and high frequency oscillatory ventilation after conventional therapy failed. Nitric oxide and high frequency oscillatory ventilation rapidly improved oxygenation allowing recovery without the need for extracorporeal membrane oxygenation. This treatment regimen should be considered as an option in high-risk infants with respiratory syncytial virus infection who meet extracorporeal membrane oxygenation criteria.     

Haplotype and interspersion analysis of the FMR1 CGG repeat identifies two different mutational pathways for the origin of the fragile X syndrome

To understand the origins of the fragile X syndrome and factors predisposing alleles to instability and hyperexpansion, we have compared the haplotype (using markers FRAXAC1, FRAXAC2, and DXS548) and AGG interspersion patterns of the FMR1 CGG repeat for 214 normal and 16 premutation chromosomes. Association testing between interspersion pattern and haplotype reveals a highly significant (P < 0.002) non- random distribution, indicating that all three markers are useful in phylogenetic reconstruction of mutational change. Parsimony analysis of the FMR1 CGG repeat substructure predicts that loss of AGG interruptions has occurred independently on many haplotypes associated with the fragile X syndrome, partially explaining the haplotype diversity of this disease. Among haplotypes found in linkage disequilibrium with the fragile X mutation, two different modes of mutation and predisposition to instability have been identified. One pathway has involved the frequent and recurrent loss of AGG interruptions from rare asymmetrical ancestral array structures. Intergenerational transmission studies suggest that these predisposed chromosomes progress relatively rapidly to the disease state. In contrast, the second mutational pathway involves a single haplotype which has maintained two AGG interruptions. Parsimony analysis of CGG repeat substructure within this haplotype suggests that larger alleles have been generated by gradual increments of CGG repeats distal to the most 3' interruption. Pedigree analysis of the intergenerational stability of alleles of this haplotype confirms a gradual progression toward instability thresholds. As a result, a large reservoir of chromosomes carrying large repeats on this haplotype exists. These chromosomes are predisposed to disease. The present data support a model in which there are at least two different mutational pathways predisposing alleles to instability and hyperexpansion associated with the fragile X syndrome.      

Apoptosis in the early human placental bed and its discrimination from necrosis using the in-situ DNA ligation technique

Extensive areas of necrosis are present in the early human placental bed. Our aim was to determine whether apoptosis is also a feature. A method was therefore required to differentiate unequivocally necrosis and apoptosis. Initially, terminal deoxynucleotide transferase-mediated dUTP nick-end labelling was used to visualize apoptotic cells. However, non-specific labelling, probably due to free DNA released by necrotic cells, was excessive; thus, in-situ DNA ligation was employed. In this technique, two DNA fragments with single-base 3' overhangs and blunt- ends were labelled with a fluorochrome and then ligated to the DNA breaks on the sections. Immunolabelling for cytokeratin or leukocyte common antigen was performed to determine the phenotype of apoptotic cells identified by the in-situ DNA ligation technique. A proportion of the dying cells was confirmed to be trophoblasts. No co-localization with leukocyte common antigen was found in this region, suggesting that maternal macrophages and natural killer cells (CD56+) were not dying by apoptosis in significant numbers. In conclusion, in-situ DNA ligation in association with immunocytochemistry can readily distinguish apoptosis from necrosis in the placental bed. The results suggest that a proportion of invading trophoblast cells are eliminated by apoptosis in early pregnancy.      

人类风湿性关节炎滑膜-软骨-NOD．scid小鼠嵌合体模型的建立

目的:建立能反应自身免疫特点的类风湿性关节炎动物模型,为进一步研究该病发病机制奠定基础。方法:实验于2006-03/12在南方医科大学实验动物中心完成。①实验材料:SPF级2～4个月龄NOD.scid小鼠20只,体质量17～22g,雌雄各半;人类风湿性关节炎滑膜组织(佛山市第一人民医院风湿科提供,患者知情同意);骨关节炎滑膜及正常软骨(南方医院创伤骨科提供,患者及供者知情同意)。②实验分组:将小鼠随机分为2组,类风湿性关节炎滑膜组和骨关节炎滑膜组,雌雄不限,每组10只。③实验过程:每组小鼠背部皮下植入的正常软骨组织,随后将类风湿性关节炎滑膜和骨关节炎滑膜植入软骨之上。④造模10周后麻醉下处死小鼠,用放射免疫法检测血清中肿瘤坏死因子α含量,移植物进行组织病理学观察,并进行组织学积分。结果:①模型鼠一般情况:实验期间NOD.scid小鼠无手摸皮骨感、活动度差、毛稀疏等典型移植物抗宿主疾病表现,模型鼠在SPF环境下10周存活率100%。②肿瘤坏死因子α含量:类风湿性关节炎滑膜组鼠血清中肿瘤坏死因子α放射含量类风湿性关节炎组明显高于骨关节炎组[(0.80±0.06),(0.70±0.03)μg/L,t=4.466,P<0.001]。③组织病理学观察:苏木精-伊红染色,骨关节炎滑膜组只见少量的滑膜细胞增生和炎症细胞,移植的滑膜组织主要被纤维组织形成的条索状物代替,无明显地软骨被侵蚀破坏发生;类风湿性关节炎滑膜组可明显见到大量的滑膜细胞增生和生化中心形成,病变部位的组织结构间质变为疏松,变为境界不清晰的颗粒状或块状无结构强嗜酸性红染物质;软骨边缘被滑膜组织侵蚀破坏明显;类风湿性关节炎滑膜组滑膜增生、软骨侵蚀和软骨降解积分均高于骨关节炎滑膜组(P<0.04)。结论:在NOD.scid体内可成功建立类风湿性关节炎动物模型。     

人心脏型脂肪酸结合蛋白的纯化与鉴定

目的:以往的心脏型脂肪酸结合蛋白多来自牛、鼠等动物心肌组织,本实验构建了人左心室心肌组织纯化心脏型脂肪酸结合蛋白的新方法。方法:实验于2005-01/03在南京医科大学第一附属医院心血管病研究所完成。①实验材料:人心室肌由南京医科大学第一附属医院心血管病研究所提供。②实验过程:取20g人左心室肌在缓冲液中匀浆,多步骤离心后以(NH4)2SO4进行盐析→再次离心→沉淀缓冲液重悬透析得蛋白粗提液→Sephadex G-75凝胶过滤→电泳确定主要蛋白条带的收集管号合并收集→QSepharose Fast Flow阴离子交换层析→聚乙二醇浓缩→缓冲液透析得人心脏型脂肪酸结合蛋白。③实验评估:以SIGMA公司人心脏型脂肪酸结合蛋白为对照标准品;以Tricine-SDS-PAGE电泳鉴定相对分子质量;以鼠抗人脂肪酸结合蛋白单克隆抗体及羊抗鼠IgG对其进行Western印迹检测鉴定其特异性。结果:①Sephadex G-75凝胶过滤柱层析结果:各组分经Tricine-SDS-PAGE电泳检测证实,部分收集管中存在相对分子质量约14400的人心脏型脂肪酸结合蛋白。②阴离子交换柱层析结果:在洗脱液NaCl浓度达6mmol/L时,出现蛋白峰,人心脏型脂肪酸结合蛋白被洗脱;NaCl浓度达20mmol/L时,蛋白峰降至基线,蛋白洗脱结束。③纯化的人心脏型脂肪酸结合蛋白鉴定结果:经电泳显示其相对分子质量约为14000,纯度约为90%;Western印迹证实其可被抗人脂肪酸结合蛋白单克隆抗体特异识别,与对照标准品SIGMA公司人心脏型脂肪酸结合蛋白结果一致。实验从20g湿重心室肌中共纯化得到15.4mg心脏型脂肪酸结合蛋白,得率为0.77mg/g。结论:Sephadex G-75凝胶过滤柱层析及阴离子交换柱层析相结合,可用于人心脏型脂肪酸结合蛋白的纯化。