肝纤维化大鼠肠道黏膜屏障改变及微生态制剂的影响

肝纤维化患者易发生细菌感染,其原因为肠黏膜屏障受损.本研究通过检测大鼠24 h尿99mTc-二乙三胺五乙酸(DTPA)排泄率,电镜下观察肠黏膜损伤情况,分析肝纤维化大鼠肠黏膜屏障损伤的特点,同时观察应用微生态制剂后的改善情况.     

西沙比利对肝硬化大鼠小肠细菌及内毒素转位的影响

目的：研究西沙比利对肝硬化大鼠小肠细菌过度生长(IBO)，细菌及内毒素转位，小肠转运时间及小肠通透性的作用。方法：正常对照组大鼠25只，肝硬化对照组大鼠25只，肝硬化治疗组20只(用等渗盐水)，另20只肝硬化大鼠用西沙比利治疗，动物均测定各种参数如细菌和内毒素转位，小肠细菌过度生长，小肠转运时间及通透性。结果：48％肝硬化大鼠发生细菌转位，与无IBO肝硬化大鼠比较，IBO肝硬化大鼠的内毒素和细菌转位发生率高，肠转远时间延长，小肠通透性增高。BT的细菌与IBO主菌群一致。与对照组比较，西沙比利处理的肝硬化大鼠肠细菌和内毒素转位及IBO发生率降低，这与肠转运时间增快及通透性降低密切相关。结论：肝硬化大鼠内毒素和细菌转位可能是由于IBO和肠通透性增加的结果，而IBO的发生可能是由于肠转运时间延长所致。西沙比利可加速小肠转运时间，改善小肠通透性，这有助于防治小肠细菌和内毒素转位。     

肠内营养对DSS诱导的溃疡性结肠炎大鼠肠道通透性的影响

目的研究肠内营养对溃疡性结肠炎大鼠肠黏膜通透性的影响。方法将40只大鼠随机分为4组,正常对照组、模型对照组、甲泼尼龙组、谷氨酰胺组,后3组大鼠自由饮用5%DSS溶液7天,建立溃疡性结肠炎模型,后2组同时分别给予甲泼尼龙及谷氨酰胺干预治疗。收集大鼠24h尿液,采用高效液相色谱分析法研究大鼠肠道通透性的情况。结果 DSS诱导的溃疡性结肠炎大鼠乳果糖尿中排出率显著增高(P0.01),甘露醇尿中排出率下降(P0.01),L/M比值在DSS诱导的溃疡性结肠炎大鼠显著增加(P0.01)。与DSS诱导的溃疡性结肠炎模型组比较,甲泼尼龙组大鼠及谷氨酰胺组大鼠乳果糖尿中排出率下降(P0.01),甘露醇尿中排出率升高(P0.01),L/M比值降低(P0.01);谷氨酰胺组较甲泼尼龙组变化明显,但两组比较无显著差异(P0.05)。结论溃疡性结肠炎大鼠结肠黏膜通透性增加,给予肠内营养可降低结肠黏膜通透性。     

缬沙坦和培哚普利对大鼠肝纤维化模型肠通透性的影响

目的 观察血管紧张素受体阻滞剂缬沙坦和血管紧张素转换酶抑制剂培哚普利对四氯化碳诱导大鼠肝纤维化模型的疗效及对其肠通透性的影响。方法 将大鼠分为A组(正常对照组)、B组(模型对照组)、C组(缬沙坦治疗组)和D组(培哚普利治疗组)，于造模第4周C组开始用缬沙坦(10mg／kg)，D组开始用培哚普利(0.5mg／kg)治疗，共4周，进行肝组织及小肠组织苏木精-伊红染包，检测血浆D乳酸、DAO和内毒素浓度。结果经治疗后肝纤维化大鼠肝小叶结构趋于正常，纤维间隔变薄，血浆D-乳酸、DAO和内毒素浓度下降。结论 培哚普利和缬沙坦能有效地减轻四氯化碳诱导肝纤维化大鼠的损伤及纤维化程度，减轻肠源性内毒素血症和肠通透性增加。     

肝硬化大鼠小肠黏膜形态结构改变与内毒素血症

目的研究药物和胆汁淤积引起的肝硬化大鼠小肠黏膜形态结构改变和血浆内毒素水平。方法分别以硫代乙酰胺(TAA)(n=10)诱导和行胆管结扎术后(BDL)(n=7)的肝硬化大鼠为模型组,另以正常大鼠(n=12)作为正常对照组,分别观察光镜和透射电镜下小肠黏膜的形态,并采用鲎试剂基质显色法测定腹主动脉血浆内毒素含量。结果光镜下观察到模型组肝硬化大鼠小肠肠黏膜绒毛稀疏、萎缩,上皮细胞坏死,黏膜水肿伴有炎性细胞浸润;电镜下观察到模型组大鼠小肠壁超微结构有明显改变,肠黏膜绒毛破坏,减少,变短,倒伏,缺失,肠黏膜紧密间隙增宽,肠黏膜杯状细胞分泌减少,肠黏膜上皮细胞内线粒体和内质网肿胀。正常对照组大鼠的小肠黏膜绒毛形态及超微结构没有明显改变。模型组大鼠的血浆内毒素水平明显高于正常对照组(P<0.01)。结论模型组肝硬化大鼠都存在小肠黏膜结构的改变和内毒素水平的增高,提示肝硬化大鼠小肠黏膜的损伤与肠源性内毒素血症密切相关。     

云母对大鼠实验性NSAIDs肠病肠道通透性的影响

背景：非甾体抗炎药（NSAIDs）是消化道损伤的常见病因。已知云母对多种原因所致的胃黏膜损伤具有保护作用,但其对小肠黏膜损伤是否同样具有保护作用尚不清楚。目的：观察云母对NSAIDs肠病肠道通透性的影响,探讨云母保护小肠黏膜的可能机制。方法：24只大鼠随机分为空白组、模型组和云母组。云母组先以12mg／ml云母混悬液1ml／100g灌胃一次。次日起三组分别以蒸馏水、0．78mg/ml双氯芬酸溶液和云母混悬液＋双氯芬酸溶液灌胃．剂量均为1ml／100g,1次／d。灌胃5d后处死大鼠,行小肠黏膜损伤大体和组织学评分,检测24h尿液乳果糖、甘露醇排出率和血清D-乳酸含量。结果：双氯芬酸可引起明显的小肠黏膜损伤,模型组大体、组织学评分中位数和24h尿液乳果糖排出率显著高于空白组（P〈0．05）,云母组小肠黏膜损伤较模型组显著减轻,乳果糖排出率显著降低（P〈0．05）。三组尿液中均未检出甘露醇．血清D-乳酸含量无明显差异。结论：云母可降低小肠通透性,对NSAIDs肠病具有一定预防保护作用,、     

模拟高原缺氧环境对大鼠小肠组织病理和肠黏膜通透性的影响

目的探讨模拟高原环境对大鼠小肠黏膜形态结构和超微结构的影响,并通过双糖吸收实验考察肠黏膜通透性的改变。方法利用减压舱模拟5 500 m海拔高度,缺氧处理3周后,光镜及透视电镜下观察小肠黏膜上皮细胞形态结构和超微结构的变化。采用HPLC法检测研究对象尿液标本中甘露醇和乳果糖排出率比值。结果与实验对照组比较,高海拔缺氧组大鼠小肠黏膜变薄、肠黏膜水肿、绒毛短缩;超微结构也显示线粒体肿胀、嵴稀疏或消失,微绒毛变短、倒伏和部分缺失,且肠黏膜细胞凋亡也较常见。高海拔缺氧组肠道的通透性显著高于实验对照组（P〈0.01）。结论高原缺氧环境可导致小肠黏膜损伤,肠黏膜通透性增加,肠黏膜屏障破坏。     

肝硬化患者肠黏膜通透性与Child—Pugh分级的相关性研究

目的探讨肝硬化患者肠黏膜通透性（IP）与Child—Pugh分级的相关性及肠道去污剂对肝硬化患者肠道屏障功能及肝功能状态的影响。方法按Child—Pugh分级标准将76例肝硬化患者分为A、B、C3组,并选择30例体检者作为对照组,采用高压液相色谱法检测各组患者尿液乳果糖／甘露醇排出比（L／M）;给予76例肝硬化患者选择性肠道去污剂,比较用药前后各组患者肝功能Child—Pugh分级和肠黏膜通透性。结果肝硬化患者尿乳果N／甘露醇排出比明显高于对照组（0．208±0．025vs0．057±0．019）,肝硬化患者按Child。Pugh分级各组尿乳果糖／甘露醇排出比也均明显高于对照组,差异有显著性（P〈0．01）;采用Spearman等级相关分析发现,肝功能Child—Pu巾评分与乳果糖／甘露醇排出比呈正相关（r=0．658,P〈0．05）;给予肠道去污药物2周后肝硬化Child-Pugh分级各组患者尿液乳果糖／甘露醇排出比与治疗前比较均明显下降（P〈0．05）,各组Child—Pugh评分均有改善。结论肝硬化患者的肠黏膜通透性与肝功能Child—Pugh评分呈正相关,即肠道通透性随肝功能下降而升高,肠黏膜通透性对于肝硬化患者的诊断和治疗有临床意义。     

吲哚氰绿排泄试验诊断早期肝纤维化的实验研究

目的 探讨吲哚氰绿（indocyaninegreen ICG）排泄试验作为肝纤维化早期诊断的敏感指标。方法 42只清洁级Wistar大鼠随机分为正常组（N组）和四氯化碳（CC14）组（C组）。C组系CC14皮下注射模型，于造模后第2，4，6，8周分别测定ICG15分钟潴留率（ICGR15），S-P免疫组化法检测肝星状细胞（HSC）活化数，H-E染色判断肝纤维化程度，并依据肝纤维化分级标准，分为肝纤维化早期（0-Ⅲ期）、肝硬化期（Ⅳ-Ⅵ期）。结果 成功建立肝纤维化模型，准确测定ICGR15。正常对照组、肝纤维化早期组、肝硬化组，三组ICGR15间存在硅著性差异（P〈0．01），早期肝纤维化组与对照组间差异具有显著性（P〈0．01），肝硬化组与对照组间差异具有显著性（P〈0.01），肝硬化组与早期肝纤维化组间差异具有显著性（P〈0．01）三组肝纤维化程度计分间存在最著性差异（P〈0.01）早期肝纤维化组和肝硬化组与对照组间均存在显著性差异（P〈0．01）肝硬化组与早期肝纤维化组间差异具有显著性（P〈0．01）三组HSC活化数间存在显著性差异（P〈0．01），早期肝纤维化组和肝硬化组与对照组间均存在显著性差异（P〈0．01），肝硬化组与早期肝纤维化组间差异具有显著性（P〈0.01）。结论 ICG排泄试验可以作为诊断早期肝纤维化的新的敏感指标。     

加替沙星在肾损害大鼠的组织分布及排泄特性

正常和肾损害造模大鼠,口服20 mg/kg加替沙星后5 min、15 min和4 h测定各组织药物浓度,并收集胆汁、尿液与粪便,测定累积排泄率.发现两组大鼠口服加替沙星后,药物快速分布在各组织中,其中肝、肾、小肠、胃分布最多,大脑未测到.正常组与肾损害组大鼠口服20 mg/kg加替沙星后48 h,胆汁、尿液与粪便中药物累积排泄率均有明显差异.提示加替沙星在肾损害模型大鼠组织分布和尿液的排泄受到影响.     

The immunoneuroendocrine role of melatonin

Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.     

Changes in connexin43, the gap junction protein of astrocytes, during development of the rat pineal gland

Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.     

Response of rat pineal melatonin to calcium, magnesium, and lithium is circadian stage dependent

Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.     

Conservative management of perforated duodenal diverticulum： A case report and review of the literature

Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.     

Presence of immunoreactive growth hormone and prolactin in the ovine pineal gland

Abstract: The use of antisera raised against bovine growth hormone (GH) and ovine prolactin (PRL) enabled the detection of related immunoreactive (ir) sequences of proteins in ovine pineal tissue. The isolation of PRL-like ir-material was accomplished using a 0.25 M ammonium sulphate (pH 5.5) extraction followed by ethanol precipitation, whereas the resulting 2.0 M ammonium sulphate (pH 7.0) precipitate contained a GH-like immunoreactivity. Gel chromatography of the GH-like immunoreactivity (Sephadex G-100) indicated the presence of several GH-like fragments ranging in the M_r range of 7,000 to 55,000. Analyses of the PRL-like ir-material found in pineal tissue on HPLC using a TSK 545-DEAE column led to the resolution into a single peak of immunoreactivity. A single peak of activity was also observed following chromatofocusing and hydrophobic interaction chromatography of the ir-peak from the TSK 545-DEAE column. The PRL-like ir-material inhibited the binding of [¹²⁵I]ovine PRL-S14 to anti-ovine PRL antibodies without showing an affinity for binding to anti-rat PRL or anti-bovine GH antibodies. Scatchard analysis of the binding of pineal PRL-like ir-material and pituitary ovine PRL-S14 to liver membranes from day-20 pregnant rats revealed similar affinity constants (K_a of 4.7 ± 0.2 × 10⁹ M^-1). In addition, the replication of Nb 2 Node rat lymphoma cells was stimulated by pineal PRL-like ir-material, an effect known to be specific for lactogenic hormones. The pineal PRL-like immunoreactivity appeared on sodium dodecyl sulfate polyacrylamide gels as a single major band of M_r 24,000. The functional status of PRL-and GH-like ir-material in the ovine pineal remains to be determined, but evidence is presented that the overall protein synthesis rate of the rat pineal responded to circulating concentrations of PRL.     

Microbiology of human immunodeficiency virus anorectal disease

PURPOSE: Individuals who are seropositive for the human immunodeficiency virus are at high risk for opportunistic infection and anorectal disorders. Little prospective information is available regarding anorectal pathogens in these patients. METHODS: One hundred sixty-three HIV-seropositive patients presented to the colorectal clinic between 1989 and 1992. Forty-seven (29 percent) patients were thought to have an infectious process and were prospectively studied using a standardized multiculture protocol. RESULTS: Mean age was 33 (range, 19–59) years. All were male; high-risk behavior accounted for 87 percent of HIV transmissions. Presenting complaints included anorectal pain (79 percent), pus per anum (28 percent), and blood per anum (26 percent). Examination revealed perianal tenderness (60 percent), condyloma (38 percent), perianal ulcers (38 percent), and anal fissures (34 percent). Sixty-six sets of cultures were performed; 28 patients had one set, 15 had two sets, and 4 had three sets. Thirty-two of these 47 patients (68 percent) had positive cultures including herpes (50 percent), cytomegalovirus (25 percent),Neisseria gonorrhoeae (16 percent), chlamydia (16 percent), acidfast bacilli (2 percent), and others (9 percent). Six of 32 patients with positive cultures had more than one organism cultured. Sixteen (50 percent) patients with positive cultures were treated medically, 8 (25 percent) were treated surgically and 8 (25 percent) were treated with both modalities. Sixty-one procedures were performed on 17 patients for condylomata. Eighteen patients had 20 procedures for abscesses, 50 percent of whom had positive cultures for other than common bowel flora; all improved. Fourteen patients underwent 33 procedures for perianal fistulas.Mycobacterium fortuitum was cultured from one patient who required 13 procedures for abscesses and fistulas. Forty-five (96 percent) patients were followed for an average of 12.5 months ±2.9 SEM (range, 1–94 months). Symptoms were improved or resolved in 22 of 32 (69 percent) patients with positive cultures and in 11 of 13 (84 percent) with negative cultures. CONCLUSIONS: Specific pathogens may often be identified in human immunodeficiency virus-seropositive patients with anorectal disorders if aggressively sought. Although patients without specific pathogens identified may be expected to improve with planned empiric treatment, positive identification allows more directed therapy.