慢性胃炎肠化生CD_(44)、CD_(44V6)及Cyclin D_1、Cyclin E的表达和意义

目的探讨慢性胃炎胃粘膜肠化生CD44、CD44V6及cyclin D1、Cyclin E表达的意义。方法利用免疫细胞化学技术对39例伴有肠化生的慢性胃炎和5例正常人胃窦粘膜的活检组织进行检查。结果正常人胃窦粘膜上皮,腺上皮对CD44、CD44V6、Cyclin D1和Cyclin E均为阴性,但在有神经内分泌样细胞的粘膜,CD44V6和cyclin D1为阳性。慢性胃炎肠化生区和不典型增生区除CD44为阴性外,CD44V6、cyclin D1和cyclin E均呈现不同的阳性反应,但未见有阳性的神经内分泌样细胞。间质细胞大都呈阳性反应。结论CD44V6、cyclin D1和cyclin E可能是胃癌前状态的早期事件,而CD44可能为胃癌晚期的标志物。     

微生态制剂治疗肝硬化肠功能紊乱患者的临床观察

目的探讨微生态制剂治疗肝硬化肠功能紊乱患者的疗效。方法选择80例肝硬化肠功能紊乱患者,随机分成治疗组和对照组。治疗组:常规保肝治疗加金双歧(4粒/次,2次/d);对照组:常规保肝治疗。疗程均为4周。结果治疗组和对照组相比,腹胀、腹泻、腹部不适症状明显改善,血氨水平降低,血浆内毒素水平下降,2组相比差异有显著性(P<0.05)。结论微生态制剂对于改善肝硬化患者临床症状有肯定的价值,并可降低血氨及血浆内毒素水平,有利于肝功能的改善。     

艾迪注射液对急性白血病患者化疗减毒增效作用及肠道菌群影响的研究

艾迪注射液可扶植肠道正常菌群生长,减轻化疗药副作用,提高白血病患者化疗疗效。方法将选择病例随机分为艾迪注射液治疗组(试验组)及常规化疗组(对照组)。观察其化疗前后肠道常驻菌(肠杆菌、肠球菌、双歧杆菌、乳酸杆菌)指标,骨髓象检查及化疗后毒副作用观察。结果各项指标同单纯化疗组相比,差异均有显著性(P<0.05或P<0.01)。结论艾迪注射液具有扶植肠道正常菌群生长的作用,与化疗合用,减轻了化疗药的毒副作用,保证了化疗的顺利进行,提高了急性白血病患者的化疗疗效。     

乳果糖对肝癌TACE后肠黏膜损伤的保护作用研究

目的了解乳果糖对肝癌TACE后患者肠黏膜损伤的保护作用。方法将54例患者随机分为2组,治疗组按常规治疗加服乳果糖,对照组按常规治疗,服药后观察全身和肠道情况并检测二胺氧化酶(DAO)的内毒素水平。结果治疗组血二胺氧化酶水平与术前相比差异无显著性(P>0.05),未应用乳果糖组血内毒素水平比术前降低(P<0.05);治疗组血内毒素水平与术前相比差异无显著性(P>0.05),而未应用乳果糖组血内毒素水平比术前升高(P<0.05)。结论乳果糖增强了肠道黏膜的屏障作用,在避免肝癌TACE后的肠道细菌易位,内毒素血症起到积极作用。     

Occurrence of rhizobia in the gut of the higher termite Nasutitermes nigriceps

Wood-eating termites feed on a diet highly deficient in nitrogen. They must complement their diet with the aid of nitrogen-fixing bacteria. Nitrogen fixation in the gut has been demonstrated, but information about nitrogen-fixing bacteria in pure culture is scarce. From the higher termite Nasutitermes nigriceps the symbiotic bacterial strain M3A was isolated, which thrives in the hindgut contents. The Gram-negative strain exhibited similarities to the species of the genus Ensifer (including Sinorhizobium) on the basis of morphological and physiological/biochemical features. The 16S rRNA gene analysis showed the highest sequence similarity of the isolate M3A to Ensifer adhaerens (>99%; ATCC 33499). The DNA-DNA hybridization revealed a similarity of 66% with E. adhaerens (NCIMB12342(T)). In contrast to the type strain the isolate M3A possesses the capacity to nodulate plant roots. This is the first report on the detailed identification of a rhizobia-related strain from the intestinal tract of animals. Strain M3A has been deposited with two culture collections (DSM10169; ATCC BAA-396).     

Interaction between Shaoyao–Gancao–Tang and a laxative with respect to alteration of paeoniflorin metabolism by intestinal bacteria in rats

Shaoyao-Gancao-Tang (SGT), a traditional Chinese herbal medicine (Kampo formulation) containing Shaoyao (Paeoniae Radix) and Gancao (Glycyrrhizae Radix), is co-administered with laxative sodium picosulfate as a premedication for relieving the pain accompanying colonoscopy. Paeoniflorin (PF), an active glycoside of SGT, is metabolized into the antispasmodic agent paeonimetabolin-I (PM-I) by intestinal bacteria after oral administration. The objective of the present study was to investigate whether the co-administered laxative (sodium picosulfate) influences the metabolism of PF to PM-I by intestinal bacteria. We found that the PF-metabolizing activity of intestinal bacteria in rat feces was significantly reduced to approximately 34% of initial levels by a single sodium picosulfate pretreatment and took approximately 6 days to recover. Repeated administration of SGT after the sodium picosulfate pretreatment significantly shortened the recovery period to around 2 days. Similar results were also observed for plasma PM-I concentration. Since PM-I has muscle relaxant activity, the present results suggest that repetitive administration of SGT after sodium picosulfate pretreatment might be useful to relieve the pain associated with colonoscopy.     

Paneth cells drive intestinal stem cell competition and clonality in aging and calorie restriction

Calorie restriction has been recently shown to increase intestinal stem cell competition and to reduce mutation fixation in young mice. However, the impact of aging on this process is unknown. By employing Confetti reporter mice, here we show that, unexpectedly, old mice have more intestinal stem cell (ISC) competition than young mice. Moreover, differently from what observed in young mice, calorie restriction, when applied at late-life, decreases this process. Importantly, we also observed a strong correlation between the ISC competition and Paneth cell number. In vivo analysis and in vitro organoid experiments indicated that Paneth cells play a major role in driving intestinal stem cell competition and crypt clonality. Taken together, our results provide evidence that increasing the number of Paneth cells can increase the number of competitive ISCs, representing a valuable therapeutic target to delay fixation of mutated intestinal stem cells.     

益生菌通过调整正常菌群缓解酒精性肝损伤的研究进展

许多临床试验表明慢性酒精性肝损伤会引起肠道菌群的失调,主要表现为双歧杆菌、乳杆菌数量减少,革兰氏阴性菌大量繁殖,破坏肠道屏障功能,增加肠道通透性,使细菌来源的内毒素大量释放出来,引起血液内毒素增加,并在肝脏中累积,超出肝脏的清除能力,导致肝损伤。本文主要综述益生菌通过调整正常菌群这一机制来缓解酒精性肝损伤的研究进展,进而深入了解酒精引起肠道菌群变化(酒精的摄入会导致肠道中拟杆菌、厚壁菌数量减少,革兰氏阴性变形菌、革兰氏阳性放线菌数量增加,同时肠道内细菌来源的内毒素水平增加)导致肝损伤的发病机制,以及益生菌如何通过调整肠道正常菌群改善酒精性肝损伤。     

Elucidating pathways of Toxoplasma gondii invasion in the gastrointestinal tract: involvement of the tight junction protein occludin

Toxoplasma gondii is an obligate intracellular parasite infecting one third of the world's population. The small intestine is the parasite's primary route of infection, although the pathway of epithelium transmigration remains unclear. Using an in vitro invasion assay and live imaging we showed that T. gondii (RH) tachyzoites infect and transmigrate between adjacent intestinal epithelial cells in polarized monolayers without altering barrier integrity, despite eliciting the production of specific inflammatory mediators and chemokines. During invasion, T. gondii co-localized with occludin. Reducing the levels of endogenous cellular occludin with specific small interfering RNAs significantly reduced the ability of T. gondii to penetrate between and infect epithelial cells. Furthermore, an in vitro invasion and binding assays using recombinant occludin fragments established the capacity of the parasite to bind occludin and in particular to the extracellular loops of the protein. These findings provide evidence for occludin playing a role in the invasion of T. gondii in small intestinal epithelial cells.