Sulfhydryl blocker-induced colitis in the rat: Immunological changes in thymus gland and colonic mucosa

The study was designed to examine the changes of thymus in sulfhydryl blocker-induced colitis. We used N-ethylmaleimide (NEM) as sulfhydryl blockers. Fasted male Sprague-Dawley rats were given 3% NEM in 1% methyl cellulose into the colon. N-ethylmaleimide treatment caused severe diarrhoea with bleeding for the first 7 days. At autopsy, adhesions, colon dilatation, and single or multiple erosions and ulcers were observed. Time-course studies revealed that the lesions were most extensive and severe 3 or 7 days after the administration of NEM. Histological examination of colon on the 3rd day after NEM treatment demonstrated mucosal erosion, oedema and extensive infiltration of neutrophils. The mucosal lesions extended into the submucosa and muscle on the 7th day after NEM treatment. Immunohistochemical studies showed that T cells and macrophages were markedly increased in the lamina propria of colonic mucosa. After 3 weeks, the infiltration of chronic inflammatory cells was observed and regeneration of the mucosa was noticed. The thymus gland was significantly decreased in weight and size on the 3rd day after NEM treatment, but the weight loss of thymus gland was regained in 3 weeks. Transient atrophy of thymus gland was noticed in this colitis model. The phenotypes of thymocytes were not influenced by NEM treatment. It is concluded that the thymus abnormalities in human ulcerative colitis are not induced in this animal model and that other chronic models are necessary for the elucidation of the immunological abnormalities, including thymus abnormalities.     

Addition of cisapride shortens colonoscopy preparation with lavage in elderly patients

Methods: The effect of pre-treatment with cisapride on colonoscopy preparation with lavage solution was compared in 120 out-patients less than 60 years and 73 out-patients 60 years or older, who were scheduled for total colonoscopy. By random allocation, patients were assigned to receive cisapride 10 mg or placebo 30 minutes before ingesting the magnesium citrate lavage solution. Results: The cleansing results and patients’acceptance did not differ significantly in the two treatment groups in either age group. The time from the start of ingesting magnesium citrate until the rectal effluent became clear was significantly shorter in cisapride-treated patients of 60 years or more. Moreover, the residual fluid volume removed by suction during colonoscopy was significantly less in the patients above aged 60 years who received cisapride. Conclusion: These findings indicate that the combination of cisapride and magnesium citrate is more effective than magnesium citrate alone in cleansing the colon for colonoscopy in elderly patients.     

Alkaline Phosphatase Isoenzymes in Carcinoma Tissue of Gastro-intestinal Tract

The enzymological and immunological properties of alkaline phosphatase (ALP) isoenzymes in carcinoma tissues of the gastro-intestinal tract were compared with those of purified human intestinal, placental and hepatic ALP's to investigate the gene expression of gastro-intestinal cancer cells. The results were as follows: ALP obtained from carcinoma tissues of 77 patients was separated into 6 bands (ALPa, ALPb, ALPc, ALPd, ALPe and ALPf) by polyacrylamide-gel disc electrophoresis. It was concluded that ALPa was similar in its enzymological and immunological properties to hepatic-type ALP, ALPb was similar to placental-type ALP (Regan ALP or Nagao ALP), ALPc to intestinal-type ALP (metaplasia ALP), ALPd to hepatoma-type ALP (Warnock's variant ALP), ALPe to intestinal-type ALP except for electrophoretic mobility, and ALPf was similar to hepatic-type ALP except for neuraminidase sensitivity. ALPb appeared in 16 out of 55 cases (29%) of gastric carcinoma, and 2 out of 21 cases (10%) of colonic carcinoma. ALPd appeared in 4 out of 55 cases (7%). ALPe appeared in 2 out of 55 cases (4%) of gastric, and 3 out o 21 cases (14%) of colonic carcinoma. ALPf appeared in 1 out of 55 cases (2%) of gastric, and 1 out of 21 cases (5%) of colonic carcinoma. These ALP isoenzymes (ALPb, ALPd, ALPe and ALPf) probably originate from the cancer cells themselves and may represent an abnormal gene expression of cancer cells in the process of onco-developmental differentiation.     

Changes in QT Interval during Exercise Testing in Patients with VVI Pacemakers

. The changes in QT intervals were studied in nine patients with normal sinus node function who had VVI pacemakers. Though PP intervals uniformly shortened during exercise, the change in QaT* intervals during exercise was variable. The correlation between PP and QaT intervals varied from case to case. A good correlation was found in only two cases (r =+0.816 or +0.897); a fair correlation was found in four cases (r =+0.672, +0.615, +0.615, or −0.669) and in the remaining three, the correlation was poor (r =+0.494, +0.467 or−0.424). In patients who are candidates for VTI pacemaker implantation, changes in QaT intervals should be assessed during exercise stress testing to determine if the intervals shorten during exercise or not.
(QaT*: Interval from the pacing spike to the apex of T-wave.)