Animals ; Cecum/microbiology* ; Hyperoxia/blood* ; Microbiota ; Rats

The experimental infection of rats with seven strains of Entamoeba histolytica were carried out according to animal ages, number of inoculated amebae, rat strain differences and rat-culture passages. The rat cecal scoring technique of Neal (1951) was utilized to measure the invasiveness of the parisite. The results are summarized and concluded as follows; 1. In the infection of Sprague-Dawley strain rat with YS9-strain and NAMRU II-stran amebae, which wem confirmed highly invasive to the membrane of cecum of rabbits in the previous reports (Cho,1968; Cross,1968), remarkab1e invasiveness was observed in the 30-day-old rat groups with the average cecal score above 5.0. Although no statistical differences of virulence by the number of inoculations showed in rat groups, the cecal scores were markedly reduced in the 50,000 amebae inoculated rats. 2. The hybrid albino rats were considered unsuitable for virulence study of E. histolytica, since the invasiveness of the amabae was inconsistant. 3. The virulences of YS 14 and YS16-strains from cyst carrier showed no virulence, YS 15 from cyst carrier and YS 24 from liver abscess were moderately invasive, and only YS25 from liver abscess showed highly invasive as with YS 9 and NAMRU II-strain amebae. By rat-culture passage, YS14-strain and YS24-strain amebae showed marked increase of invasiveness. It was presumed that the rat-culture passage should be indispensably supplememed in the studies on the virulence of E. histolytica.
Adult ; Animals ; Cecum/microbiology ; Entamoeba histolytica/*pathogenicity ; Female ; Human ; Korea ; Male ; Middle Aged ; Rats ; Virulence

Inulin has been used as a prebiotic to alleviate glucose and lipid metabolism disorders in mice and humans by modulating the gut microbiota. However, the mechanism underlying the alleviation of metabolic disorders by inulin through interactions between the gut microbiota and host cells is unclear. We use ob/ob mice as a model to study the effect of inulin on the cecal microbiota by 16S rRNA gene amplicon sequencing and its interaction with host cells by transcriptomics. The inulin-supplemented diet improved glucose and lipid metabolism disorder parameters in ob/ob mice, alleviating fat accumulation and glucose intolerance. The α diversity of gut microbial community of ob/ob mice was reduced after inulin treatment, while the β diversity tended to return to the level of wild type mice. Interestingly, Prevotellaceae UCG 001 (family Prevotellaceae) was obviously enriched after inulin treatment. A comparative analysis of the gene expression profile showed that the cecal transcriptome was changed in leptin gene deficiency mice, whereas the inulin-supplemented diet partially reversed the changes in leptin gene-related signaling pathways, especially AMPK signaling pathway, where the levels of gene expression became comparable to those in wild type mice. Further analysis indicated that Prevotellaceae UCG 001 was positively correlated with the AMPK signaling pathway, which was negatively correlated with markers of glycolipid metabolism disorders. Our results suggest that the inulin-supplemented diet alleviates glucose and lipid metabolism disorders by partially restoring leptin related pathways mediated by gut microbiota.
AMP-Activated Protein Kinases ; metabolism ; Animals ; Cecum ; enzymology ; metabolism ; microbiology ; Gastrointestinal Microbiome ; drug effects ; Inulin ; therapeutic use ; Leptin ; genetics ; Male ; Metabolic Diseases ; drug therapy ; enzymology ; metabolism ; microbiology ; Mice ; Mice, Obese ; Prebiotics ; Signal Transduction ; drug effects ; Transcriptome

OBJECTIVETo observe the pathological changes of the intestinal mucosa in rats with severe abdominal infection.

METHODA total of 60 SD rats were divided randomly into control group and experimental group (n=30), and in the latter group, the rats underwent cecal ligation and puncture (CLP) while those in the former had only laparotomy. The jejunum and ileum were sampled on postoperative days 1, 2 and 4 for optical and electron microscopic observations. The positivity rate of blood bacterial culture and plasma level of endotoxin were determined in the rats.

RESULTSNo abnormal changes were observed with either optical and electron microscope in the small intestinal mucous membrane of rats in the control group, but in rats of the experimental group, microscopic examination revealed interstitial edema, vascular engorgement and neutrophil infiltration in the small intestine mucous membrane and the submucosa, and electron microscopy demonstrated loose and disorderly arrangement of the microvilli of the intestinal epithelium. Plasma endotoxin level in rats in the experimental group was 5- to 12-fold higher than that in the control group. The positivity rates of blood bacterial culture were 20%, 30% and 10% on postoperative days 1, 2 and 4 respectively in the experimental group, but were all zero in the control group.

CONCLUSIONPathologic lesions in the intestinal mucosa occur during the early stage of severe abdominal infection in rats as the result of bacteria and endotoxin translocation.

Animals ; Bacteria ; isolation & purification ; Bacterial Infections ; blood ; microbiology ; pathology ; Bacterial Translocation ; Cecum ; Endotoxins ; blood ; Female ; Intestinal Diseases ; etiology ; microbiology ; pathology ; Intestinal Mucosa ; microbiology ; pathology ; ultrastructure ; Intestine, Small ; microbiology ; pathology ; Ligation ; adverse effects ; Male ; Microscopy, Electron ; Punctures ; adverse effects ; Random Allocation ; Rats ; Rats, Sprague-Dawley