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Intestinal Lesions (intestinal + lesion)
Selected AbstractsDNA Adduct Levels and Intestinal Lesions in Congenic Rapid and Slow Acetylator Syrian Hamsters Administered the Food Mutagens 2-Amino-1-methyl-6-phenylimidazo[4,5- b]pyridine (PhIP) or 2-Amino-3-methylimidazo[4,5- f]quinoline (IQBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 6 2000Inger-Lise Steffensen Epidemiological studies indicate that rapid acetylators with a high intake of well-done red meat have an increased risk of colorectal cancer. Arylamine N -acetyltransferase enzymes (E.C. 2.3.1.5) activate carcinogenic heterocyclic amines found in the crust of fried meat via O -acetylation of their N -hydroxylamines to reactive intermediates that bind covalently to DNA and produce mutations. Syrian hamsters as well as humans express two N -acetyltransferase isozymes (NAT1 and NAT2) which differ in substrate specificity and genetic control. Nucleic acid substitutions in the NAT2 gene segregate individuals into rapid, intermediate and slow acetylator phenotypes. In the present paper, we examined the role of the polymorphic NAT2 acetylator genotype in carcinogenesis induced by the food mutagens 2-amino-1-methyl-6-phenylimidazo[4,5- b]pyridine (PhIP) or 2-amino-3-methylimidazo[4,5- f]quinoline (IQ) by comparing Syrian hamster lines congenic at the NAT2 locus. No differences were found between rapid and slow acetylator congenic hamsters in levels of intestinal PhIP-DNA adducts. In contrast to previous studies in rats, no carcinogen-related induction of the preneoplastic lesions aberrant crypt foci or tumors was found in the intestines of rapid and slow acetylator congenic Syrian hamsters administered PhIP or IQ. [source] Helicobacter equorum: prevalence and significance for horses and humansFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 1 2009Hilde Moyaert Abstract Helicobacter equorum colonizes the caecum, colon and rectum of horses. The agent is highly prevalent in <6-month-old foals. In adult horses, the prevalence of H. equorum seems to be rather low, but these animals may harbour low, subdetectable numbers of this microorganism in their intestines. So far, no association could be made between the presence of H. equorum and clinical disease or intestinal lesions in adult horses. Further research is necessary to elucidate the pathogenic potential of this bacterial species towards young foals. Helicobacter equorum DNA was not detected in human faeces, indicating that this microorganism does not commonly spread from horses towards humans. [source] Protective effect of rebamipide on indomethacin-induced intestinal damage in ratsJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 10 2001Hiroyuki Mizoguchi Abstract Background and Aim: We evaluated the effect of rebamipide (2-(4-chlorobenzoylamino)-3-[2(1H)-quinolinon-4-yl] propionic acid), a novel anti-ulcer drug, on indomethacin-induced small intestinal lesions in rats. Methods: The animals were administered indomethacin (10 mg/kg, s.c.), and they were killed 24 h later. Rebamipide (30,300 mg/kg) was administered p.o. twice, 30 min before, and 6 h after indomethacin. Results: Indomethacin caused hemorrhagic lesions in the rat small intestine, accompanied by an increase in enterobacterial translocation, inducible nitric oxide synthase (iNOS) and myeloperoxidase (MPO) activities, as well as thiobarbituric acid (TBA) reactants, and these changes were significantly prevented by the supplementation with 16,16-dimethyl prostaglandin E2 (dmPGE2; 10 ,g/kg, i.v.) or the pretreatment of animals with the antibiotic ampicillin. Treatment of the animals with rebamipide dose-dependently prevented the development of intestinal lesions, and this effect was mimicked by i.v. administration of superoxide dismutase (SOD: 3000 U/kg) + catalase (CAT: 5000 U/kg). The protection by rebamipide was accompanied by a significant suppression of the increase in both MPO and iNOS activities, and a complete inhibition of the increase in TBA reactants, while SOD + CAT significantly inhibited the increase of MPO activity and TBA reactants, but not iNOS activity. The bacterial translocation following indomethacin was also significantly decreased by either rebamipide or SOD + CAT. Conclusion: These results confirmed the importance of enterobacteria and iNOS/NO in the pathogenesis of indomethacin-induced small intestinal lesions, and suggested that rebamipide prevents the development of these lesions, probably by its radical scavenging action. [source] Review article: stem cell therapies for inflammatory bowel disease , efficacy and safetyALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 8 2010O. García-Bosch Aliment Pharmacol Ther 2010; 32: 939,952 Summary Background, Drugs available for the treatment of inflammatory bowel disease fail to induce and maintain remission in a significant number of patients. Aim, To assess the value of stem cell therapies for treatment of inflammatory bowel disease based on published studies. Methods, Publications were identified through a MEDLINE search using the Medical Subject Heading terms: inflammatory bowel diseases, or Crohn's disease, or ulcerative colitis, and stem cell, or stromal cell or transplant. Results, Haematopoietic stem cell therapy as a primary treatment for inflammatory bowel disease was originally supported by animal experiments, and by remissions in patients undergoing transplant for haematological disorders. Later, transplantation specifically performed for patients with refractory Crohn's disease showed long-lasting clinical remission and healing of inflammatory intestinal lesions. Use of autologous nonmyeloablative regimens and concentration of the procedures in centres with large experience are key in reducing treatment-related mortality. Initial trials of mesenchymal stem cell therapy with local injection in Crohn's perianal fistulas had positive results. Conclusions, Autologous haematopoietic stem cell transplant changes the natural course of Crohn's disease, and may be a therapeutic option in patients with refractory disease if surgery is not feasible due to disease location or extension. [source] Effect of Tissue Processing on Assessment of Endoscopic Intestinal Biopsies in Dogs and CatsJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 1 2010M.D. Willard Background: Prior studies failed to detect significant association between hypoalbuminemia and small intestinal lesions. Hypothesis: Use of pictorial templates will enhance consistency of interpathologist interpretation and identification of intestinal lesions associated with hypoalbuminemia. Animals: Tissues from 62 dogs and 25 cats examined as clinical cases at 7 referral veterinary practices in 4 countries. Methods: Retrospective, observational study. Histopathology slides from sequential cases undergoing endoscopic biopsy were examined by 4 pathologists by pictorial templates. Changes for 9 microscopic features were recorded as normal, mild, moderate or severe, and 2- and 4-point scales were tested for consistency of interpretation. Logistic regression models determined odds ratios (OR) of histologic lesions being associated with hypoalbuminemia while , statistics determined agreement between pathologists on histologic lesions. Results: There was poor agreement (,=,0.013 to 0.3) between pathologists, and institution of origin of slides had effect (,= 1.0 for 3 of 4 lesions on slides from Institution 5) on agreement between pathologists on selected histologic features. Using 2 point as opposed to 4-point grading scale increased agreement between pathologists (maximum ,= 0.69 using 4-point scale versus maximum ,= 1.0 using 2-point scale). Significant association (P= .019, .04; 95% OR = 3.14,10.84) between lacteal dilation and hypoalbuminemia was found by 3 pathologists. Conclusions and Clinical Importance: Substantial inconsistency between pathologists remains despite use of pictorial template because of differences in slide processing. Distinguishing between mild and moderate lesions might be important source of the disagreement among pathologists. [source] | ||||||||||