实验小鼠肠道正常菌群

在动物肠道中栖息的细菌，构成了肠道正常菌群。实验动物的质量与肠道菌群的状态有着十分密切的联系，肠道菌群平衡状态在维持动物机体的生理状态、正常功能，以及抵抗外袭菌方面起着重要的作用。小鼠肠道中，每克肠内容物含有上亿个菌体，可分为10～15个属，上百个种。肠道正常菌群的主要菌属有双歧杆菌、拟杆菌(类杆菌)、肠球菌、乳杆菌、梭杆菌、真杆菌。不同品系的小鼠之间，各种菌的数量有所不同。本文简要介绍了近年来对小鼠肠道正常菌群的研究进展。     

褪黑素对结肠黏膜上皮细胞氧化应激的影响

目的 探讨褪黑素对大鼠结肠黏膜上皮细胞氧化应激的影响。方法 在分离培养正常大鼠结肠黏膜上皮细胞基础上，利用FeSO4 H2O2产生*OH攻击制备结肠黏膜细胞氧化损伤模型，同时预先加入褪黑素并观察损伤减轻程度。实验设正常对照组、模型对照组、5-氨基水杨酸给药组(0.1mmol／L)，褪黑素给药组(0．01、0．1、l.0mmol／L)。培养一定时间后，取上清测乳酸脱氢酶(LDH)、丙二醛(MDA)、谷胱甘肽过氧化物酶(GSHPx)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、一氧化氮(NO)和黏液含量。结果 模型组大鼠结肠黏膜上皮细胞：MDA、LDH和NO水平增高，CAT、GSHPX、SOD和黏液含量减少。不同剂量褪黑素呈剂量依赖性的减少LDH释放，抑制MDA和NO的形成，恢复黏液、CAT、GSHPX及SOD水平。结论 褪黑素对大鼠结肠黏膜氧化损伤具有保护作用。     

反式二羟环氧苯并芘对人支气管上皮细胞中HER2/neu基因表达的影响

目的探讨环境致癌物苯并(a)芘代谢物反式二羟环氧苯并芘(BPDE)对人支气管上皮细胞HER2/neu基因表达的影响。方法利用半定量RT-PCR、SYBR GreenI实时定量RT-PCR(QRT-PCR)、Western blot及免疫细胞化学方法分别检测经2.0μmol/L反式BPDE诱发人支气管上皮细胞恶性转化细胞(16HBE-T)与对照DMSO溶剂组未恶性转化细胞(16HBE-N)之间HER2/neu基因mRNA和蛋白表达水平的差异,及两组细胞内HER2/neu蛋白表达定位分析。结果经几种不同方法检测反式BPDE恶性转化人支气管上皮细胞中HER2/neu基因mRNA和蛋白水平都比对照溶剂组细胞(16HBE-N)表达显著升高(P<0.05)。HER2/neu蛋白定位在胞膜。结论反式BPDE诱发人支气管上皮细胞恶性转化存在HER2/neu表达增高,其可能与原癌基因HER2/neu被激活作用有关。     

小肠内固定术治疗粘连性肠梗阻

目的评价小肠内固定术治疗粘连性肠梗阻的疗效。方法回顾性分析28例粘连性肠梗阻行小肠内固定术患者的临床资料。结果28例患者中有5例发生切口感染,无手术死亡和小肠瘘发生。其中25例患者平均随访23.6个月,1例肠梗阻复发,保守治疗后好转。结论小肠内固定术是治疗预防粘连性肠梗阻可行、有效的方法,但需要注意手术操作细节。     

Detailed Analysis of Mucosal Restoration of the Small Intestine After the Cavitary Two-Layer Cold Storage Method

Small bowel transplantation (SBT) is associated with a high incidence of infectious complications because of ischemia/reperfusion (I/R) mucosal injury concomitant with potent immunosuppression. In this study, we evaluated whether the cavitary two-layer method (cTLM) could reduce I/R injury and allow early mucosal restoration, particularly after prolonged preservation and transplantation. Canine heterotopic segmental SBT was performed immediately without preservation (group 1), after 24-h preservation in UW solution (group 2) or by the cTLM (group 3). The graft samples were taken 1 h after reperfusion and on days 1, 4 and 7. We assessed graft mucosa with detailed microscopic and electromicroscopic analyses. In Group 3, histological injury and cell apoptosis after transplantation were significantly alleviated and rapidly recovered to a similar level of group 1. The mucosal restoration was morphologically completed within 4 days. In contrast, in group 2, more pronounced mucosal injury and delayed recovery were noted. Crypt cell proliferation activity was well maintained in groups 1 and 3 throughout the experimental period. Our ultrastructural analysis suggested that mitochondrial integrity achieved by the cTLM was a basal mechanism under the prompt mucosal restoration. The cTLM could reduce I/R injury, facilitate mucosal regeneration and restore the nearly normal structure early after SBT.     

参附注射液对大鼠胰腺移植受体小肠肠粘膜屏障的保护作用

目的探讨参附注射液（SF）对大鼠胰腺移植受体肠粘膜屏障的保护作用及机制。方法24只糖尿病大鼠随机分为缺血再灌注组（IR组。n=12），参附注射液预处理组（SF组．n=12），12只正常大鼠为对照组，IR组和SF组大鼠均接受胰腺移植，再灌注后5d检测小肠通透性和吸收功能，检测血清TNF-α、NO、SOD和淀粉酶活性，取受体空肠粘膜组织检测小肠粘膜粘膜湿重、微绒毛高度及宽度、MDA含量及MPO活性，同时取肠系膜静脉血、肠系膜淋巴结、肝及脾组织进行细菌培养，观察细菌易位情况。结果再灌注后SF组血清TNF—α含量（P〈0．01）、淀粉酶活性（P〈0．01）、MDA含量（P〈0．01）、MPO活性（P〈0．01）、小肠通透性（P〈0．01）、细菌易位率（P〈0．01）和小肠粘膜损伤程度均低于IR组；血清NO和SOD含量、小肠吸收功能均高于IR组（P〈0．01）。结论SF预处理可保护大鼠胰腺移植受体小肠肠粘膜屏障，降低细菌易位率，机制可能与降低胰酶活性、减少TNF—α生成、减轻PMNs粘附与聚集、增加NO和SOD含量有关。     

急诊左半结肠一期切除吻合术25例治疗体会

目的探讨急诊左半结肠切除一期肠吻合的可行性。方法腹腔探查完后，用布带结扎横结肠，游离肠系膜后，于预切除肠段的上端切开作肠外减压，挤压排空粪便，切除病变肠管，端端吻合，术后作肛管扩张，停留肛管引流，胃肠减压。结果全部病人预期痊愈出院，无发生吻合口漏和腹腔污染。结论该法有利于吻合口的愈合，增加左半结肠一期切除吻合的安全性，减少第2次手术痛苦，可推荐为左半结肠急诊切除一期吻合的良好方法。     

p38 MAPK对嗜酸性粒细胞和支气管上皮细胞共培养时细胞因子释放的调控作用

目的 了解嗜酸性粒细胞和支气管上皮细胞相互作用诱导细胞因子释放的p38 MAPK信号转导通路.方法 用CD16磁珠抗体分离外周血中嗜酸性粒细胞,以嗜酸性粒细胞和支气管上皮细胞(BEAS-2B)接触共培养为实验模型,观察SB 203580对细胞培养上清液中细胞因子浓度的影响.细胞因子浓度采用ELISA和流式细胞微珠方法测定.结果 SB 203580能够有效抑制BEAS-2B细胞释放IL-6、IL-8(P＜0.05)和嗜酸性粒细胞释放IL-8(P＜0.01).SB 203580对嗜酸性粒细胞与BEAS-2B细胞接触共培养诱导的IL-6、IL-8和IP-10释放具有显著抑制作用(P＜0.001).结论 嗜酸性粒细胞、BEAS-2B细胞单独或相互作用时均通过p38 MAPK信号转导通路释放细胞因子.     

组织工程心肌补片对黑山羊陈旧性心肌梗死心功能和建立侧支循环的影响

目的探讨自体骨髓间充质干细胞(m arrow m esenchym a l stem ce lls,M SC s)-小肠黏膜下层(sm a llin testina l subm ucosa,S IS)构建的组织工程心肌补片,移植于陈旧性心肌梗死区后对心功能及缺血区建立侧支循环的影响。方法将已建立急性心肌梗死模型后6周的黑山羊16只,随机分为实验组和对照组,实验组抽取自体骨髓,经体外分离M SC s,进行培养、传代,以第3代细胞行5-B rdU标记并与S IS支架材料复合培养5 d,制备M SC s-S IS组织工程心肌补片。将其缝合至陈旧性心肌梗死区;对照组仅行假手术处理。于植入后6周,采用超声心动图观察两组动物心功能变化,数字减影血管造影选择性左冠状动脉造影观察缺血心肌侧支循环的建立。结果术后6周实验组及对照组:心博出量、左心室射血分数分别为42.81±4.91、37.06±4.75 m l和59.20%±5.41%和44.56%±4.23%,组间差异均有统计学意义(P<0.05);左心室舒张末期容积、左室收缩末期容积分别为72.55±8.13、83.31±8.61 m l和29.75±5.98、46.25±6.68 m l,组间差异均有统计学意义(P<0.05);左心室舒张功能各项指标分别为:E峰最大速度分别为54.85±6.35 cm/s和43.14±4.81cm/s(P<0.01);A峰最大速度分别为52.33±6.65 cm/s和56.91±6.34 cm/s(P>0.05)。超声心动图显示对照组左室腔扩张明显,室壁运动明显减弱,梗死区呈瘤样扩张,局部室壁反常运动;实验组左室腔明显小于对照组,室壁运动较对照组强,心尖梗死区扩张不明显。选择性左冠状动脉造影见实验组左冠状动脉前降支远端与回旋支间明显侧支循环建立。结论M SC s-S IS构建的组织工程心肌补片移植于黑山羊陈旧性心肌梗死区后侧支循环建立,心功能有明显改善作用。     

Role of Integrin CD103 in Promoting Destruction of Renal Allografts by CD8+ T Cells

Infiltration of CD8(+)TCRalphabeta(+) T-effector populations (CD8 effectors) into graft epithelial compartments has long been recognized as a key lesion in progression of clinical renal allograft rejection. While the afferent phase of allograft immunity is increasingly well-defined, the efferent pathways by which donor-reactive CD8-effector populations access and ultimately destroy the graft renal tubules (rejection per se) have received remarkably little attention. This is an important gap in our knowledge of transplantation immunology, because epithelial compartments comprise the functional elements of most commonly transplanted organs including not only kidney, but also liver, lung, pancreas, and intestine. Furthermore, there is increasing evidence that attack of graft epithelial elements by CD8-effector populations not only causes short-term graft dysfunction but is also a major contributor to development of chronic allograft nephropathy and late graft loss, which now represent the salient clinical problems. Recent studies of the T-cell integrin, alpha(E)beta(7) (CD103), have provided insight into the mechanisms that promote interaction of CD8 effectors with graft epithelial compartments. The purpose of this communication is to review the known properties of the CD103 molecule and its postulated role in the efferent phase of renal allograft rejection.