重组人生长激素（rhGH）对肠梗阻大鼠肠黏膜屏障和免疫屏障的实验研究

目的探讨重组人生长激素（rhGH）对肠梗阻大鼠肠黏膜屏障和免疫屏障的保护作用。方法结扎SD大鼠末端回肠,使肠腔狭窄75％,制作成不完全性肠梗阻动物模型;并应用rhGH6d（每日1次）,观察其回肠黏膜形态学、回肠液sIgA改变及肠道细菌移位情况。结果肠梗阻时,大鼠回肠壁表现为肌层变薄,黏膜厚度减少,肠绒毛变短、变细;回肠液中sIgA浓度减少及细菌移位数量增加;应用rhGH后,回肠黏膜厚度、肠绒毛结构保持相对完整,回肠液中sIgA浓度升高,细菌移位减少。结论肠梗阻时,大鼠肠道黏膜屏障和免疫屏障功能受损,给予外源性rhGH可以较好保护受损肠道的黏膜屏障和免疫屏障功能。     

胃肠黏膜屏障功能障碍及肠道细菌或内毒素移位对机体的影响

胃肠黏膜屏障功能障碍与肠道细菌和(或)内毒素移位,会导致机体不同的病症和内源性感染等,给临床医师对疾病的防治带来了难以预料的挑战.文章通过对胃肠黏膜屏障及其障碍、胃肠黏膜屏障与肠道细菌和(或)内毒素移位以及肠道内毒素移位对机体的影响等方面的探讨,使临床医师对疾病病理生理和防治等方面的知识和相关信息有更多的了解和认识,在临床工作中对遇到的临床问题会有更深和更广的理解和思考.     

Th17细胞在肠黏膜免疫中的作用

肠黏膜是人体最大的淋巴器官,它与呼吸道黏膜、泌尿生殖道黏膜等一起构成机体的第一道防御体系.肠黏膜经常抵御细菌、病毒、食物抗原、非甾体类抗炎药等的侵袭,若肠黏膜免疫系统遭受破坏,机体发生感染性疾病、自身免疫性疾病等.因此,肠黏膜免疫功能正常对机体的健康非常重要.Th17细胞是近年来发现的一类不同于Th1和Th2细胞的T细...     

细菌移位在小儿外科领域的研究现状

细菌移位最先是指肠道内活菌通过黏膜上皮进入固有层,随后进入肠系膜淋巴结甚至远处器官的现象;后来扩展为包含所有微生物及其产物通过肠道黏膜屏障的现象;目前是指原存在于肠腔内的细菌和（或）内毒素,通过某种途径越过肠黏膜屏障,肠系膜淋巴结、门静脉系统,继而进入体循环及肝、脾、肺等远隔器官的过程。本文就细菌移位在小儿外科领域的研究进展综述如下。     

肠黏膜屏障的组成及其与肝损伤关系的研究进展

健康肠道的完整黏膜屏障是阻止物质易位的防线。目前动物模型和人类病理学研究证明,肠黏膜屏障功能的变化与肝病的发生和治疗有着密切的联系。该文就肠黏膜屏障的组成、其与肝损伤的关系以及潜在治疗靶点作一综述。     

新生猪仔肠缺血再灌注所致细菌移位的实验研究

目的 了解新生儿肠缺血再灌注损伤对细菌移位的影响。方法 采用新生猪仔非阻塞性肠缺血再灌注模型,观察不同程度缺血再灌注所致肠道细菌移位及肠粘膜上皮损伤情况。结果 对照组无细菌移位,中度缺血仅有肠系膜淋巴结细移位移,中度缺血再灌注,重度缺血,重度缺血再灌注均导致肠系膜淋巴结,外周血,肝,脾细菌移位,缺血再灌注组细菌移痊数明显高于仅有缺血组（Ｐ〈０．０１）,重度缺血再灌注可见肠粘膜上皮损伤。结论 新生猪     

小儿急性阑尾炎细菌移位及相关性的研究

目的 探讨小儿急性阑尾炎细菌移位的发生与阑尾组织一氧化氮合成酶(NOS)、血清一氧化氮(NO)的关系.方法 应用聚合酶链反应(PCR)定性检测全血细菌DNA(所有细菌共有的16SrRNA、大肠杆菌BG);腹腔液体及肠系膜淋巴结细菌培养;免疫组织化学方法定量检测阑尾组织NOS的表达;酶联免疫吸附试验(ELISA)定量检测不同时间血清中NO的变化.结果 对照组及单纯性阑尾炎组均未检出细菌DNA,化脓性阑尾炎组16SrRNA阳性率为70%,BG阳性率为60%,肠系膜淋巴结细菌培养阳性率(大肠杆菌)为50%,腹腔液体为40%.阑尾炎组NOS平均灰度值与对照组之间有明显差异(P<0.01).阑尾炎组术前NO浓度与术后组、对照组间均有差异(P<0.05).NOS平均灰度值与NO浓度呈相关性,二者与细菌移位的表达密切相关.结论 小儿急性阑尾炎发生细菌移位,而细菌移位可能与NOS、NO相关,及时检测血清细菌DNA和NO对小儿急性阑尾炎细菌移位的诊治有一定的临床价值.     

小儿急性肠套叠细菌移位的相关研究

目的 探讨小儿急性肠套叠细菌移位及机制.方法 应用聚合酶链反应(PCR)定性检测细菌共有的16 SrRNA和大肠杆菌特异性β半乳糖苷酶基因BG;肠系膜淋巴结细菌培养;免疫组织化学方法检测组织Bcl-2、Bax的表达.结果 正常对照组全血16SrRNA、大肠杆菌BG未检出,空气灌肠复位组16SrRNA阳性率30%,BG阳性率20%;手术复位组16SrRNA阳性率50%,BG阳性率60%,肠系膜淋巴结培养阳性率为50%;肠坏死肠切除组16SrRNA阳性率60%,BG阳性率70%,肠系膜淋巴结培养阳性率为60%;与对照组相比,肠套叠手术组凋亡调控基因Bcl-2、Bax表达明显升高,Bcl-2/Bax比值变小.结论 小儿急性肠套叠应用PCR技术早期可诊断细菌移位,而肠套叠肠缺血再灌注损伤诱导Bcl-2、Bax蛋白表达,是引起肠黏膜细胞凋亡最终发生细菌移位可能的机制.     

肠黏膜屏障在炎症性肠病的发病机制和治疗中的研究进展

炎症性肠病是一类反复发作的胃肠道慢性非特异性炎症,可见于任何年龄,发病率逐年升高,且发病机制仍不十分明确.肠黏膜屏障是指正常肠道具有的将肠腔内物质与机体内环境隔离的功能,它能够防止致病性抗原侵入黏膜下层组织,维持机体内环境的相对稳定和机体的正常生命活动.肠黏膜屏障功能的损伤与多种胃肠道疾病如炎症性肠病的发生密切相关.肠黏膜机械屏障、免疫屏障、生物屏障中的任一功能环节或其相互作用障碍,都有可能导致疾病的发生.明确肠黏膜屏障损伤在炎症性肠病发病中的具体机制,有效维持和修复肠黏膜屏障功能,有望成为治疗炎症性肠病的新策略.     

益生菌对肠黏膜屏障的作用机制

肠黏膜屏障是指正常肠道具有的将肠腔内物质与机体内环境隔离,防御外来抗原及致病性病原体侵入黏膜下层组织的功能,维持机体内环境的相对稳定和机体的正常生命活动.肠黏膜屏障功能的损伤与多种胃肠道疾病的发生密切相关.益生菌是指摄取后在肠道达到一定数量能够对宿主起有益作用的活微生物,它能够改善或预防多种胃肠道疾病,其主要机制为益生菌能够通过多种途径维持肠黏膜屏障功能.该文就益生菌对肠黏膜屏障功能的具体作用机制作一综述.     

Detection of bacterial translocation during intestinal distension in rats using the polymerase chain reaction

To investigate whether distension causes bacterial translocation (BT), a rat model reported earlier by us was used and to detect the presence of bacterial DNA in blood by polymerase chain reaction (PCR) assay, the most sensitive detection method to date. In 4 groups of 4-week-old Wistar-albino rats a total of 15 animals each were included. In the 1st group (distension+gavage), 10¹⁰ Escherichia coli colonies were given via gavage and distension was carried out by rectal air inoculation. In the 2nd group (gavage), animals were inoculated with E. coli and no distension was induced. The 3rd group (distension) were only distended and no bacteria were inoculated. The control group were neither distended nor inoculated with E. coli. Blood samples were collected 3 h after manipulations and both blood cultures and PCR assays were performed. According to the PCR results BT was evident in 80% of group 1, 20% of group 2, and 33% of group 3 animals. BT was not determined in the control group. Significantly low percentages of positivity were observed in blood cultures in all groups (P < 0.05). These results confirm reports that BT occurs in the presence of distension and that PCR is a superior way of determining BT. Thus, it would be advisable to utilize PCR technology in cases where the possibility of distension exists, as early intervention might be useful before any severe clinical pathology (sepsis, multiple-organ-system failure) becomes evident. Accepted: 19 December 2000     

Bacterial colonization and intestinal mucosal barrier development

The intestinal tract is colonized soon after birth with a variety of ingested environmental and maternal microflora. This process is influenced by many factors including mode of delivery, diet, environment, and the use of antibiotics. Normal intestinal microflora provides protection against infection, ensures tolerance to foods, and contributes to nutrient digestion and energy harvest. In addition, enteral feeding and colonization with the normal commensal flora are necessary for the maintenance of intestinal barrier function and play a vital role in the regulation of intestinal barrier function. Intestinal commensal microorganisms also provide signals that foster normal immune system development and influence the ensuing immune responses. There is increasingly recognition that alterations of the microbial gut flora and associated changes in intestinal barrier function may be related to certain diseases of the gastrointestinal tract. This review summarizes recent advances in understanding the complex ecosystem of intestinal microbiota and its role in regulating intestinal barrier function and a few common pediatric diseases. Disruption in the establishment of a stable normal gut microflora may contribute to the pathogenesis of diseases including inflammatory bowel disease, nosocomial infection, and neonatal necrotizing enterocolitis.     

Intestinal obstruction in children in India

A total of 243 cases of intestinal obstruction were seen in the Paediatric Surgery Unit of S. S. Hospital, Varanasi, during a period of 2.5 years. Surgical exploration was required in 85%; 15% responded to conservative treatment. The male/female incidence was 75.72%:24.28%. Intussusception (16%), Ascaris bolus obstruction (13.5%), enteric perforation (12.3%), and abdominal tuberculosis (11%) formed the majority of the cases. Morbidity and mortality due to intestinal obstruction and its complications is high in India due to delayed medical attention, poor primary health services, health ignorance, and poor socioeconomic status.Offprint requests to: A. N. Gangopadhyay     

The effects of sucralfate and selective intestinal decontamination on bacterial translocation

Sucralfate is widely used as a cytoprotective agent in patients with peptic ulcer and other intestinal mucosal damage. In this study, the effects of sucralfate and/or selective intestinal decontamination with gentamycin on bacterial translocation (BT) in rats with experimentally-induced mechanical jaundice were investigated. Seventy-five adult male Wistar albino rats were divided into five groups of 15 each. In all except a sham group, we performed ligation of the common bile duct (CBD) via a vertical laparatomy. After surgery, the rats in group 1 were treated with oral sucralfate (5 mg/kg per day); those in group 2 underwent oral gentamycin therapy (5 mg/kg per day) for 5 days. Group 3 rats were treated with sucralfate and gentamycin for 5 days subsequent to the operation. The rats in group 4 served as controls, and received only 0.9% saline solution. Group 5 was a sham group. After 5 days of surgery, all rats were killed; the mesenteric lymph nodes (MLN), liver, and a segment of terminal ileum were harvested aseptically. The collected tissues were cultured in McCaunkey medium and chocolate agar. For each specimen, the colony-forming units (CFU) were calculated and the percentage of viable translocated micro-organisms was counted. In all rats who had ligation of the CBD, high numbers of bacteria were demonstrated in the liver, MLN, and ileum. In the liver of rats with sucralfate and/or gentamycin treatment, there was a marked reduction in CFU compared to the control group. Similarly, in the MLN measurements of CFU were higher in the control rats than the study groups. In both McCaunkey and chocolate media, the numbers of bacteria in control rats were significantly higher than in the study groups (P < 0.001). However, among the study groups themselves there was no significant difference in CFU in any of the specimens or culture media (P > 0.05). Experimentally-induced mechanical jaundice from ligation of the CBD causes significant BT in rats. Sucralfate and/or gentamycin may reduce the degree of BT from the bowel mucosa. We did not find any difference in protection from BT between sucralfate and gentamycin or both in rats with experimentally-induced mechanical jaundice. Accepted: 12 July 1999     

肠道共生细菌和肠上皮屏障间关系的研究进展

人类出生后,其胃肠道黏膜表面与肠道共生细菌和致病性病原体密切接触.肠道上皮屏障作为抵御细菌入侵的第一道防线,通过模式识别受体产生对致病性病原体杀伤性免疫应答,而对共生细菌产生保护性应答.肠上皮细胞在对共生细菌形成免疫耐受,维持肠道免疫稳态中发挥重要作用.共生细菌能协助肠道上皮抵御病原体侵袭,并调节肠道免疫发育和免疫功能.在共生细菌和宿主肠道之间形成免疫平衡,否则易引起肠道炎症疾病.该文从共生细菌对宿主肠道的作用、肠上皮屏障对共生细菌形成免疫耐受机制以及肠道上皮屏障对共生细菌识别平衡破坏引起的疾病等多方面对共生细菌和肠上皮屏障之间关系作一综述.     

Congenital mesenteric hernia causing intestinal obstruction in children

A mesenteric hernia is one type of intraperitoneal hernia. There is no hernia sac in this situation but only a mesenteric defect, which is present at birth. Strangulated mesenteric hernia is a rare cause of intestinal obstruction especially in the pediatric population. Between January 1996 and January 2006, four patients with intestinal obstruction were determined to have congenital mesenteric hernia at Chang Gung Children’s Hospital. Patients consisted of three boys and one girl, ranging in age from 2 years 5 months to 5 years 4 months. All patients presented with symptoms and signs indicative of intestinal obstruction. On physical examination, all patients appeared to be severely ill. A shock-like state was associated with necrosis of the strangulated bowel in two patients. A palpable abdominal mass was present in one patient with volvulus of small bowel. The plain abdominal radiography and the ultrasound scan also showed dilatation of the small bowel and excluded intussusception. All the patients underwent laparotomy after initial resuscitation. During laparotomy, three patients had incarceration of small bowel through the small mesenteric defect, and another one had volvulus with gangrenous bowel entrapped within a large mesenteric defect. The defects ranged in size are from 2 to 7 centimeters in diameter. Simple reduction of the incarcerated bowel with repair of the defect was performed in two patients, resection of gangrenous bowel and primary anastomosis was required in one patient, and resection with end ileostomy was needed in another one patient. There was no postoperative mortality in our patients. Conclusion: A mesenteric hernia is a rare cause of intestinal obstruction, especially in children. Open exploration is the only way to establish a clear anatomic diagnosis.     

儿童肠梗阻的诊断和鉴别诊断

肠梗阻是小儿外科常见的急腹症,病因复杂,病情多变.不但可引起肠管本身解剖和功能上的改变,还可导致全身性生理紊乱,处理不及时可能造成短肠综合征等并发症.及时诊断肠梗阻并明确原因,对抢救、逆转危重状态和减少并发症的发生有重要意义.