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1.
目的 探讨血管活性肠肽(vasoactive intestinal peptide,VIP)对内毒素(脂多糖,lipopolysaceberide,LPS)致休克大鼠肺损伤后Toll样受体(Toll-like receptor,TLR)2和TLR4 mRNA表达的影响.方法 40只SD大鼠,随机分为LPS组(16只)、LPS+VIP组(16只)和对照组(8只).LPS组尾静脉注射LPS(E.coli O_(55)B_5)10 mg/kg;LPS+VIP组尾静脉注射LPS 10 ms/kg后注射VIP 5 nmol/kg;对照组尾静脉注射等容量生理盐水.分别于注射后6 h和24 h处死,留取肺标本,RT-PCR检测肺TLR2/4 mRNA表达,并观察24 h时肺组织病理变化.结果 (1)肺组织病理改变:制模24 h时.光镜和透射电镜下,LPS组见肺泡间隔弥漫性增宽、炎性细胞浸润,隔内毛细血管不同程度充血,肺泡壁增厚,肺泡腔结构破坏、炎性细胞浸润、出血、间质水肿、细胞器破坏,LPS+VIP组病变较轻.(2)TLR2/4 mRNA表达:注射LPS后6 h、24 h,肺组织TLR2/4 mRNA表达升高(F=16.638,P=0.000;t=5.876,P=0.000);24 h时LPs+VIP组TLR2/4 mRNA表达低于LPS组(F=16.676,P=0.000;t=3.9,16,P<0.001).结论 LPS致休克大鼠肺损伤时,肺组织TLR2/4 mRNA表达增强.VIP可减轻LPS所致肺损伤,其机制可能与下调重要炎症基因TLR2/4 mRNA表达有关.  相似文献   

2.
目的:探讨肠三叶因子对内毒素血症幼鼠肠组织Toll样受体(TLR)2、4表达的调节及对肠组织损伤的影响。方法:24只10日龄Wistar幼鼠随机分为正常对照组(NS组,n=8,生理盐水1 mL/kg腹腔注射);内毒素血症组(LPS组,n=8,LPS 5 mg/kg 腹腔注射);肠三叶因子组(ITF组,n=8,重组肠三叶因子 0.1 mL/只+LPS 5 mg/kg腹腔注射)。于腹腔注射后3 h处死,留取远端回肠组织观察肠组织病理改变,RT-PCR检测肠组织TLR2、4-mRNA的表达。结果:光镜下NS组肠组织结构正常,ITF组和LPS组均可见间质和上皮细胞水肿,ITF组较LPS组病变明显减轻。ITF组肠组织TLR2 mRNA 表达较NS组、LPS组明显增高(P<0.01); 而TLR4 mRNA表达较NS组和LPS组明显下降(P<0.01)。结论:肠三叶因子可减轻内毒素血症幼鼠肠组织损伤,这种保护作用可能与其下调TLR4 mRNA的表达相关。  相似文献   

3.
目的 探讨肠三叶因子(ITF)对肠组织NF-KB及TNF-α的调节及与肠损伤保护作用的关系.方法 24只10日龄的Wistar幼鼠随机分为正常对照组(NS组),脂多糖(LPS)组,ITF组,每组8只.NS组予9 g/L盐水1 mL/kg腹腔注射;LPS组予LPS(5 g/L)5 mg/kg腹腔注射;ITF组予重组ITF(5 g/L)0.1 mL/只+LPS 5 mg/kg腹腔注射.于腹腔注射后3h处死幼鼠,留取远端回肠组织,HE染色,光镜下行肠组织病理学检查.RT-PCR检测肠组织NF-κB mRNA表达水平.免疫组织化学检测肠组织NF-κB蛋白定位表达.ELISA法检测肠组织TNF-α分泌水平.结果 光镜下NS组肠组织结构正常,ITF组和LPS组均可见肠黏膜间质和上皮细胞水肿,ITF组较LPS组明显减轻;ITF组肠组织NF-KB mRNA和NF-κB蛋白表达均较LPS组明显下降(P均<0.01);ITF组肠组织TNF-α分泌较LPS组明显减少(P<0.01).结论 ITF减轻肠组织损伤的保护作用可能与其下调NF-KB mRNA和蛋白的表达及降低炎性介质TNF-α的分泌相关.  相似文献   

4.
目的 研究LGR5肠道干细胞在内毒素血症肠黏膜损伤修复中的作用,是否可以通过调节干细胞的增殖分化来促进肠黏膜的修复.方法 21日龄健康Wistar幼鼠,随机分成对照组、脂多糖(lipopolysaccharide,LPS)组和胰高血糖素样肽-2(glucagon-like peptides 2,GLP-2)组.LPS组及GLP-2组腹腔注射LPS 5 mg/kg,GLP-2组腹腔注射LPS 1 h后腹腔注射GLP-2 250 μg/kg;对照组腹腔注射生理盐水1 ml/kg;在LPS注射后6h、24 h及72 h取末端回肠.光镜及电镜观察各组回肠上皮结构改变,免疫组织化学、RT-PCR方法检测肠道干细胞标记物LGR5的表达.结果 LPS注射后6h,LPS组及GLP-2组大体可见肠管充血、水肿.光镜下可见绒毛断裂、倒伏,炎性细胞浸润,腔内可见渗出液,24h及72h LPS组及GLP-2组肠黏膜损伤逐渐修复,绒毛逐渐生长,GLP-2组较LPS组修复明显,72h GLP-2组上皮基本恢复正常.免疫组织化学可见LGR5抗体标记在隐窝内,LPS组及GLP-2组在绒毛底部及绒毛处可见LGR5抗体标记,GLP-2组表达多于LPS组.RT-PCR检测,LPS组LGR5 mRNA表达6 h(0.13±0.05)、24h(0.16±0.05)、72 h(0.16±0.04)均明显高于对照组(0.12 ±0.03),差异均有统计学意义(P均<0.05);GLP-2组LGR5 mRNA表达6h(0.52±0.09)、24 h(0.73 ±0.14)、72 h(0.48 ±0.24),明显高于LPS组,差异均有统计学意义(P均<0.05).结论 内毒素血症肠上皮黏膜炎症损伤后,肠上皮干细胞增殖分化,可能参与修复炎症损伤后的肠黏膜;外源性给予GLP-2可促进内毒素血症肠黏膜损伤的修复.  相似文献   

5.
目的 探讨肾上腺素对内毒素(lipopolysaccharide,LPS)所致大鼠肠道损害的保护作用及其作用机制.方法 50只SD大鼠随机分为5组(每组10只):对照组:大鼠静脉输注0.9%生理盐水24 ml/(kg·h);LPS组:大鼠静脉注射LPS 6m/kg后,静脉输注生理盐水2.4 ml/(kg·h);低、中和高剂量肾上腺素组:大鼠静脉注射LPS 6 mg/kg后,分别静脉输注肾上腺素0.12 μg/(kg·min)、0.3μg/(kg·min)和0.6μg(kg· min).在LPS注射前、注射后2h和注射后6h3个时点取血,检测血清肿瘤坏死因子(TNF)-α、白细胞介素(IL)-1β和IL-10水平,并在24h观察肠道的组织病理学变化.结果 LPS组大鼠在LPS注射后2h血清TNF-α浓度为(1164±145) ng/L,IL-1β浓度为(521±68)ng/L,IL-10浓度为(303±20) ng/L,较对照组均明显升高(P<0.05).病理结果显示,LPS组小肠黏膜充血、水肿、出血及炎症细胞浸润,上皮细胞坏死、脱落.高剂量肾上腺素组2h血清TNF-α浓度为(576±105) ng/L,2h和6h的IL-10浓度分别为(424±29) ng/L和(24.5±14) ng/L,与LPS组相比血清TNF-α水平明显降低(P<0.05)且IL-10水平明显升高(P<0.05),但IL-1β水平无明显变化(P>0.05).高剂量肾上腺素组大鼠肠道病理损伤明显减轻.中、低剂量肾上腺素组各时间点血清细胞因子水平与LPS组比较,差异无统计学意义(P>0.05),未见肠道病理损害减轻.结论 肾上腺素可以通过抗炎作用减轻LPS素诱导的肠道损害.  相似文献   

6.
目的 探讨血小板活化因子(PAF)受体拮抗剂在内毒素血症幼年大鼠肠道黏液蛋白(MUC2)损伤中的作用.方法 18日龄Wistar大鼠,随机分为对照组和实验组,实验组又分为内毒素组(LPS组)、PAF受体拮抗剂预防组(简称预防组)和PAF受体拮抗剂治疗组(简称治疗组),每一时点(注射LPS后1.5、3、6、24、48、72 h)各8只,注射LPS后1.5、3、6、24、48、72 h取回肠.LPS组和对照组分别腹腔注射内毒素5 mg/kg及生理盐水lⅡd/J‘g;预防组于注射LPS前30 min、治疗组于注射LPS后30 min腹腔注射PAF受体拮抗剂BN52021 5 ng/kg.用透射电镜做形态学检查.应用免疫组化方法检测肠黏膜中MUC2变化.结果 电镜下对照组肠微绒毛及细胞间紧密连接未见异常.LPS 组上皮细胞连接增宽;微绒毛变细、稀疏,部分断裂、脱落;细胞器受损.预防组和治疗组改变较LPS组轻.对照组MUG2蛋白均匀地分布于回肠上皮细胞表面,MUC2蛋白染色阳性的杯状细胞轻度膨胀、扩张.实验组细胞表面MUC2阳性染色明显减少,分布不均.对照组MUC2表达平稳且水平较高,其他3组均下降,LPS组降低最为明显,低谷在注射后6 h(0.1841±0.0047),明显低于对照组(0.2091±0.0060)(P<0.01),预防组及治疗组变化趋势同LPS组,各时点MUC2均较LPS组高,方差分析提示组内及组间比较差异有统计学意义(P<0.05).结论 PAF在内毒素血症肠道黏液屏障功能损伤中可能起一定作用,预防和治疗性应用PAF受体拮抗剂BN52021可减轻肠损伤.  相似文献   

7.
肠三叶因子在内毒素致幼鼠肠损伤中的作用及意义   总被引:4,自引:1,他引:3       下载免费PDF全文
目的:探讨内毒素(LPS)致幼鼠肠损伤中二胺氧化酶(DAO)及肿瘤坏死因子(TNF-α)的变化及基因重组肠三叶因子(rITF)的保护作用,为临床治疗提供实验依据。方法:Wistar幼鼠10日龄96只分为3组,A组:生理盐水对照组;B组:LPS组;C组:LPS+rITF组,每组32只。以生理盐水(1mL/kg),EcoliO55:B5(1mL/kg)、rITF(0.1mL/只、配制浓度5g/L)腹腔注射后2,6,24,72h断头处死动物,取动静脉混合血,测血DAO活性。留取肠组织,免疫组化法检测TNF-α蛋白含量,PCR法检测TNF-αmRNA表达。同时作电镜观测肠组织超微结构变化。结果:B组血浆DAO活性自LPS作用后2h即开始升高,至6h达到最高值,较A组差异有显著性(1.519±0.13U/Lvs1.081±0.04U/L,P<0.01),72h仍持续高值;C组血浆DAO活性较B组明显下降(P<0.01或P<0.05);与A组6h比较差异有显著性(P<0.01),其余各时间点差异无显著性(P>0.05);B组TNF-α积分光密度含量明显高于A组,以LPS作用后6h达高峰(37247.64±3387.59vs6191.02±482.32,P<0.01),C组TNF-α含量较B组明显降低,但仍高于A组(P<0.01);TNF-αmRNA在A组各时间点有微弱的表达,在B组各时间点表达明显增强,较A组差异显著(P<0.01);而C组各时间点表达明显减少,较B组差异显著(P<0.01或P<0.05)。电镜下肠组织超微结构:A组正常,B组变化明显,C组变化较B组减轻。结论:ITF可降低血浆DAO活性,抑制肠组织TNF-αmRNA及蛋白表达,减轻LPS所致幼鼠肠损伤,发挥保护作用。  相似文献   

8.
目的探讨大鼠内毒素休克模型的肠道病变、血液TNF-α、IL-1β、IL-10改变和血管活性肠肽(VIP)的保护作用。方法28只成年SD大鼠随机分成3组:对照组(8只),内毒素休克组(10只)和血管活性肠肽干预组(10只)。内毒素休克组大鼠左侧颈外静脉注射内毒素10mg/kg,血管活性肠肽干预组注射同量内毒素后,即刻注射血管活性肠肽5nmol,对照组注射等容量生理盐水。各组于实验开始后1、2、4、6h分别留取血液,用ELISA法测定TNF—α、IL-1β和IL-10水平。大鼠自然死亡和实验持续6h时放血处死,留取小肠段,进行病理学检查。结果内毒素休克组和血管活性肠肽干预组血液TNF—α、IL-1β和IL-10水平与对照组相比呈现升高(P〈0.05 or P〈0.01),其中TNF—α于2h时达到高峰点,IL-1β和IL-10持续升高至6h时间点。血管活性肠肽干预组TNF—α和IL-1β升高幅度低于内毒素休克组,IL-10升高幅度高于内毒素休克组(P〈0.01)。注射内毒素后小肠光镜和电镜下均显示肠段病变,内毒素休克组病变明显较血管活性肠肽干预组严重。结论血管活性肠肽可减轻内毒素休克大鼠肠道病变,其保护机制与下调促炎症细胞因子和上调抑炎症细胞因子的表达有关。血管活性肠肽是脓毒症休克治疗中有潜力的免疫调节物质。  相似文献   

9.
目的 探究Toll样受体(TLR)阻断剂对小鼠肠黏膜上皮细胞间紧密连接蛋白ZO-1的影响及对核转录因子-κB (NF-κB)和肿瘤坏死因子-α(TNF-α)的影响。方法 将32只BALB/C小鼠分为对照组、模型组、TLR4处理组、TLR2处理组(n=8),腹腔注射LPS建立内毒素血症小鼠模型,TLR4处理组、TLR2处理组在腹腔注射LPS同时分别给予TLR4抗体和TLR2抗体(10 μg/只)腹腔注射,对照组以生理盐水替代。取各组小鼠远端小肠组织,采用RT-PCR及免疫组化法检测ZO-1、NF-κBp65及TNF-α的mRNA和蛋白定位表达。结果 模型组ZO-1 mRNA及蛋白表达明显低于对照组(P < 0.05),NF-κBp65、TNF-α mRNA及蛋白表达明显高于对照组(P < 0.05);TLR4处理组及TLR2处理组ZO-1 mRNA及蛋白表达明显高于模型组(P < 0.05),NF-κBp65、TNF-α mRNA及蛋白表达明显低于模型组(P < 0.05);TLR4处理组与TLR2处理组ZO-1、NF-κBp65、TNF-α mRNA及蛋白表达比较差异无统计学意义(P > 0.05)。结论 抗TLR2、TLR4单克隆抗体可减少核转录因子的激活,抑制炎症因子大量分泌,保护紧密连接蛋白,有望对治疗肠源性感染疾病提供新的思路。  相似文献   

10.
目的 探讨促红细胞生成素(EPO)对感染致新生大鼠脑损伤保护作用的最佳应用时机及其相关机制.方法 2日龄(P2)新生SD大鼠按随机数字表法分为4组,分别为对照组(A组)、脂多糖(LPS)感染组(B组)、早期EPO干预组(C组)、晚期EPO干预组(D组).A、B、C组P2新生大鼠连续5d(P2-P6)分别腹腔注射相应药物:等容积9 g/L盐水+等容积EPO空白对照品、0.6 mg/kg LPS+等容积EPO空白对照品、0.6mg/kg LPS+5 000 IU/kg EPO;D组P2新生大鼠连续5d(P2-P6)腹腔注射0.6 mg/kg LPS,P7开始连续腹腔注射5 000 IU/kg EPO 5 d(即P7-P11).A、B2组分别于P2(腹腔注射第1次药物后6h)、P7、P12,各随机数字表法抽取10只新生大鼠取脑,以矢状缝为标志分为左右半脑,右侧脑应用酶联免疫吸附法检测脑组织EPO受体(EPOR)水平,左侧脑应用反转录-聚合酶链反应(RT-PCR)方法检测EPOR mRNA水平;A、B、C3组于P7随机数字表法选取10只新生大鼠灌注取脑,余续养,4组均于P12灌注取脑,应用免疫组织化学方法检测髓鞘碱性蛋白(MBP)、胶质纤维酸性蛋白(GFAP)及EPOR的表达,采用HE染色观察各组大鼠脑组织的病理改变.结果 1.HE染色示B组海马锥体细胞界限不清、层次紊乱,细胞数目减少,脑室扩张,周围白质有囊性软化区域形成;EPO干预组较B组病理改变减轻,早期干预组更明显.2.B组较A组EPOR蛋白及mRNA表达增加,随日龄的增加EPOR与EPOR mRNA表达有下降趋势.3.B组MBP表达(107.46±3.65)较A组(146.78±3.13)明显减少(P<0.05),EPO干预组较B组表达增加,且C组(126.25±4.42)较D组(117.35±3.42)增加更明显(P<0.05).4.B组GFAP表达(P7、P12分别为141.46±11.92、149.48±13.59)较A组(P7、P12分别为120.63±13.32、119.74±12.48)增加(P<0.05),P12时EPO干预组表达较B组降低,C组(134.59±12.19)与D组(137.27±13.87)差异无统计学意义(P>0.05).结论 EPO对出生后感染所致的脑白质损伤有保护作用,且甲期应用优于晚期,其机制可能与感染可使新生大鼠脑组织EPOR表达增加及EPOR表达随日龄增加而降低有关.  相似文献   

11.
 Solitary intestinal fibromatosis (SIF) is a very rare condition, with only 13 cases reported. We present a new case of SIF causing neonatal intestinal obstruction and review the literature on this condition. SIF appears to be a condition of infancy and carries a very good prognosis after segmental resection. Accepted: 20 March 2000  相似文献   

12.
Using porcine small intestinal submucosa in intestinal regeneration   总被引:4,自引:0,他引:4  
Small intestinal submucosa (SIS) is an unusual tissue that promotes constructive tissue remodeling when applied as a xenogeneic material. The aim of our experimental study was to assess its effectiveness in intestinal regeneration. Twenty white New Zealand rabbits were anesthetized and underwent celiotomy. A 6-cm antimesenteric incision was created at the jejunal segment. An elliptical SIS graft measuring 6 cm long and 2 cm wide was sutured to the jejunal defect as a patch graft. Thirteen living rabbits were divided into groups of three and the grafts were harvested at postoperative weeks 2, 4, and 6. The obtained specimens were evaluated for gross and histologic appearance. In morphometric examination, in the 2, 4, and 6 weeks groups, the diameters of grafted intestines were larger than preoperatively by 50%, 25%, and 25% respectively; also the grafts had contracted to 0%, 25%, and 50% of their original sizes respectively. At the end of 2 weeks, the grafts were intact without evidence of epithelial regeneration. By 4 weeks, intestinal tissue regeneration was started, and epithelial coverage of the grafts was detected. The grafts were covered with a complete intestinal mucosa at 6 weeks. Remarkable regeneration marked fibroplasia, angiogenesis, and mild mononuclear cell infiltration had also occurred throughout the grafts at 6 weeks. Porcine SIS appeared an effective biodegradable scaffold, facilitating regeneration of intestinal tissue. These results suggest that SIS may be useful to increase the mucosal surface of intestine and may provide a new substance for short gut syndrome in the future.  相似文献   

13.
肠三叶因子属于三叶肽家族,是一类较新的对肠黏膜有保护作用的因子.它在肠杯状细胞大量合成,能抵抗蛋白酶的消化,且在保护肠道黏膜的完整性、促进肠黏膜损伤后的重建与修复及在肠黏液细胞的抗凋亡中有重要的作用.迄今,很多炎性肠病中都缺少有效的治疗方法,肠三叶因子的研究为肠道疾病的治疗开辟了治疗新途径.该文对肠三叶因子的结构、分布、对肠黏膜保护和修复作用可能的分子机制和调节因素作一综述.  相似文献   

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16.
Adult intestinal allografts have demonstrated high immunogenicity in human transplantation, making the search for new and more favorable grafts an actual problem. Accepting that fetal and newborn immune systems are relatively immature, their intestines could be ideal sources for organ donation. The purpose of this study was to compare the immunogenicity of fetal, newborn, and adult intestine for selection of the least antigenic. Using a bidirectional rat model for immunologic responses, 116 small-bowel transplantations were done: 36 fetal, 40 newborn, and 40 adult grafts. Two histocompatibility barriers and different immunosuppression regimes were used. For fetal and newborn intestines, free grafts into the omentum of adult recipients were done; for adult intestines, accessory grafts in adult recipients of the same age, using vascular anastomoses. The diagnosis of graft rejection and graft-versus-host disease (GVHD) was based on histology of hematoxylin and eosin-stained biopsies from target organs. Recipients of fetal and newborn grafts did not show signs of GVHD, while 12% of the adult group did (P < 0.05). Rejection was less severe in fetal and adult (P > 0.05) than in newborn (P < 0.05) intestinal transplantation. Treatment with 10 mg/kg per day cyclosporine prevented rejection in 70% of fetal and 75% of adult grafts, while all newborn grafts were rejected. Under no immunosuppression, or with low doses of cyclosporine (2 mg/kg per day), all groups showed histologic signs of rejection in almost all cases, the fetal intestine being the least affected. Concerning histocompatibility barriers, grafts were usually less damaged in the weaker transplantation subgroups. Our data indicate that fetal intestine is the least immunogenic of the three grafts studied, suggesting that it will be the most suitable tissue for organ donation. Accepted: 8 November 1999  相似文献   

17.
AIM: To elucidate how spontaneous localized intestinal perforation (SLIP) is related to intestinal morphological features such as dilatation in very-low-birthweight (VLBW) infants. METHODS: The medical records of 13 VLBW infants (<1500 g) undergoing laparotomy between 1983 and 2003 for presumed SLIP were retrospectively reviewed. Clinical findings including maternal, prenatal and perinatal factors were analysed, and the clinical and surgical findings upon laparotomy were compared. RESULTS: Postnatal pathological conditions included patent ductus arteriosus (n=7), sepsis (n=2), respiratory distress syndrome (n=7), intraventricular haemorrhage (n=2), an indwelling catheter via the umbilical vein (n=1) and pneumonia (n=1). Indomethacin was used in seven neonates with patent ductus arteriosus, and dexamethasone preventive therapy was employed in one neonate for bronchopulmonary dysplasia. Operative findings revealed a localized small punched-out perforation in the ileum. Five patients had intestinal dilatation: two with a perforation in the middle of the dilated intestine, and three with a perforation proximal to the region of dilatation. The muscularis propria was absent in the dilated intestine of four patients. CONCLUSION: This study found no significant relationship between perforation and dilatation of the intestine. Perforation may occur in any portion of the ischaemic intestine when circulatory failure becomes severe, and is not necessarily restricted to the dilated intestine. We believe that SLIP and intestinal dilatation may occur on the same basis in low-birthweight infants; however, the disease process may be aetiologically different.  相似文献   

18.
Advancements in donor management, organ preservation and operative techniques, as well as immunosuppressive therapies, have provided children with intestinal failure and its complications a chance not only for enteral autonomy but also long-term survival through intestinal transplantation (ITx). First described in the 1960’s, experience has grown in managing these complex patients both pre- and post-transplant. The goals of this review are to provide a brief history of intestinal transplantation and intestinal rehabilitation in pediatric patients, followed by focused discussions of the indications for ITx, induction and maintenance immunosuppression therapies, common post-operative complications, and outcomes/quality of life post-transplant.  相似文献   

19.
The field of intestinal transplantation has experienced dramatic growth since the first reported cases 3 decades ago. Improvements in operative technique, donor assessment and immunosuppressive protocols have afforded children who suffer from life-threatening complications of intestinal failure a chance at long-term survival. As experience has grown, newer diseases, with more systemic manifestations have arisen as potential indications for transplant. After discussing the historical developments of intestinal transplant as a backdrop, this review focuses on the specific pre-operative indications for transplant as well as the great success that intestinal rehabilitation has witnessed over the past decade. A detailed discussion of evolution of immunosuppressive strategies is followed a general review of the common infectious complications experienced by children after intestinal transplant as well as the current long- and short-term results, including a section on new research on the quality of life in this challenging population of patients.  相似文献   

20.
Primary intestinal trichobezoars are uncommon clinical entities. Two such cases in children are reported along with a review of the literature.  相似文献   

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