Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0010346 (Crohn's disease)
 21,615 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A comparison of routine and special histochemical methods that were applied to the epithelial mucins of small intestine from patients with Crohn's disease and from normal controls showed that the normal small intestine (ileum) goblet cells secrete a predominantly non-sulphated sialomucin and that, in contradistinction to the colon, the neuraminidase insensitivity of the sialic acids of the small intestine was not due to either O-acylation at C4 or an ester substituent at C1. Presumably this implies that the protection against enzyme attack afforded to the mucosa by the mucin coat in the small intestine utilises a different mechanism from that in the colon and that, although in many respects the small intestinal mucins in Crohn's disease, and in normal controls are similar, there is an increase in side-chain O-acylated sialic acids in such mucins in Crohn's disease. This difference has not been described before, probably because it can be seen only after staining such sections by the PAT/KOH/PAS and the PBT/KOH/PAS techniques.
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PMID:Histochemical comparison of the epithelial mucins in the ileum in Crohn's disease and in normal controls. 7 52

The role of the physiologic barrier function of the small bowel and its possible role in health and disease has attracted much attention over the past decade. The intestinal mucosal barrier for luminal macromolecules and microorganism is the result of non-immunologic and immunologic defense mechanisms. The non-immunologic mechanisms consist of intraluminal factors such as gastric acid, proteolytic activity, and motility and of mucosal surface factors like mucin and the microvillous membrane. The immunologic mechanisms include secretary IgA and cell-mediated immunity. Both types of mechanism are not completely mature at birth. Maturation of this barrier is not finished before the 2nd year of life. One of the aspects of the mucosal barrier function can be estimated by the intestinal permeability (IP) for macromolecules. We use the differential sugar absorption test (SAT), in which the ratio of urinary excretion of a relatively large molecule, lactulose, is compared with that of a relatively small molecule, mannitol, after oral ingestion. Although the small intestine is permeable to certain macromolecules in normal developmental conditions, an increased IP could be involved in the pathophysiology of several diseases, including infectious diarrhea, food allergy, celiac disease, and Crohn's disease. It can be concluded that IP, as measured with the SAT, reflects the state of the mucosal barrier and is altered in several gastrointestinal diseases. The SAT is a non-invasive IP test that can be of diagnostic help to demonstrate alterations in the small-mucosal barrier function and may be useful to evaluate therapeutic interventions.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Intestinal permeability in pediatric gastroenterology. 129 42

1. Normal colonic mucin is heavily sulphated and this increases its resistance to degradation by bacterial enzymes. Any defect in mucus sulphation could therefore be important in the pathogenesis of ulcerative colitis. 2. Rectal biopsies taken at colonoscopy from patients with ulcerative colitis (n = 9), patients with Crohn's disease (n = 6) and control subjects (n = 16) were cultured for 24 h in the presence of N-[3H]acetylglucosamine and [35S]sulphate. Mucin was then extracted and purified, and the ratio of [35S]sulphate to N-[3H]acetylglucosamine incorporated into pure mucin was assessed. 3. The ratio of [35S]sulphate to N-[3H]acetylglucosamine incorporated into mucin was significantly reduced in rectal biopsies taken from patients with ulcerative colitis (0.463, 0.305-0.703, geometric mean and 95% confidence intervals) compared with control subjects (0.857, 0.959-1.111, P < 0.01). In patients with Crohn's disease the reduction in this ratio (0.559, 0.378-0.829) did not quite reach statistical significance (P = 0.06). There was no difference between the ratio of [35S]sulphate to N-[3H]acetylglucosamine incorporated into mucin in Crohn's disease and that in ulcerative colitis (P = 0.26). 4. In control subjects the ratio of [35S]sulphate to N-[3H]acetylglucosamine incorporated into mucin was higher in the rectal biopsies (0.882, 0.618-1.022) than in their paired proximal colonic biopsies (0.602, 0.421-0.861; P < 0.01), but this regional variation was not observed in either ulcerative colitis (rectum: 0.450, 0.262-0.773; right colon: 0.470, 0.321-0.690, P = 0.3) or Crohn's disease (rectum: 0.459, 0.260-0.815; right colon: 0.492, 0.260-0.929, P = 0.8).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Sulphation of colonic and rectal mucin in inflammatory bowel disease: reduced sulphation of rectal mucus in ulcerative colitis. 848 52

Ultrastructural changes that occurred in chronic active ulcerative colitis and Crohn's disease were investigated and compared to normal as well as to higher grades of dysplasia in adenomas and carcinomas. A greater number of immature absorptive cells, undifferentiated and intermediate cells were seen as compared to normal. One case of Crohn's and two cases of chronic ulcerative colitis including one with coexisting carcinoma showed increased number of vesicles and electron-dense bodies (EDB) in the absorptive cells and increased heterogeneity of mucin droplets in goblet cells and presence of atypical secretory cells (ASC). Higher grades of dysplasia characterised by large numbers of atypical secretory cells were not seen in the present series and provide no relationship between the atypical ultrastructural features and increased risk of malignancy. However, the number of cases investigated is too small and a large series is required to clarify the significance of observations such as increased number of electron-dense bodies and vesicles in the apical cytoplasm and presence of atypical secretory cells.
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PMID:Ultrastructural study of inflammatory bowel disease. 145 81

A panel of 12 monoclonal antibodies were produced by immunization of Balb/c mice with small bowel epithelial cells obtained from a patient with active well-documented Crohn's disease. The clones were derived by screening with immunofluorescence microscopy; those with staining patterns suggestive of mucin directed epitopes were chosen for study. Several distinct patterns of staining reactivity were noted, including reagents with homogeneous, luminal, heterogeneous and peripheral goblet cell activity. In addition, SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting analysis revealed reactivity to high molecular weight mucin. The reactive antigen was resistant to proteinase digestion. No endoneuraminidase activity was detected; however, one neuraminidase sensitive sialic acid epitope was demonstrated. Confirmation of glycoprotein epitopes was accomplished by testing purified mucins from several areas of the gastrointestinal tract by ELISA. Finally, individual small bowel goblet cell heterogeneity was demonstrated by immunofluorescence, Western blotting, and antibody affinity chromatography. These data demonstrate both by morphology and specific binding of antibody affinity chromatography a significant degree of small bowel goblet cell mucin heterogeneity.
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PMID:Characterization and heterogeneity of monoclonal antibodies directed to intestinal mucin derived from Crohn's disease small bowel. 187 17

The relationship between histologic changes at resection margins and anastomotic recurrence was evaluated in patients with Crohn's disease. Pathology and medical records from 1960 to 1977 identified 100 patients who met the following criteria: 1) no prior surgery for Crohn's disease, 2) small bowel or small bowel and colonic resection with anastomosis done for Crohn's disease at the Cleveland Clinic, and 3) resection margins available for microscopic analysis. The following histologic features of the margins were evaluated: edema, inflammation, lymphoid aggregates, pyloric metaplasia, fibrosis, cryptitis and crypt abscesses, ulcers, granulomas, villous shortening, mucin depletion, neuronal hyperplasia, and transmural inflammation. Additionally, margins were categorized as histologically normal, showing nonspecific changes, showing changes suggestive of Crohn's disease, and showing changes diagnostic for Crohn's disease. Anastomotic recurrence occurred in 50 patients after an average follow-up period of 11.5 years. Cumulative recurrence-free rates for the four margin categories were not significantly different. Anastomotic recurrence was not associated with any clinical or histologic feature or combination of features.
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PMID:Do microscopic abnormalities at resection margins correlate with increased anastomotic recurrence in Crohn's disease? Retrospective analysis of 100 cases. 191 26

Previous reports of a selective mucin subclass defect in ulcerative colitis have been reassessed using high performance chromatography (Superose 6 and Mono Q) for mucin purification and fractionation coupled with analysis of the fractions obtained using a combination of enzyme linked lectin and mucin antibody assays. Mucin samples purified from snap frozen rectal biopsy specimens obtained from patients with ulcerative colitis (n = 12), Crohn's disease (n = 5), and non-inflammatory bowel disease control subjects (n = 9) were subject to ion exchange chromatography using a continuous 0-0.35 mol/l NaCl salt gradient with a final 2.5 mol/l NaCl step. In all samples the major proportion (mean (SD) 86.7 (8.9)%) of the mucin detectable by wheat germ agglutinin binding eluted between 0.15 and 0.35 mol/l NaCl with no significant difference in elution profile between ulcerative colitis and control subjects. Significant elution of glycoprotein at less than 0.15 mol/l NaCl did occur, however, when a lower molecular weight mucin containing fraction which contained concanavalin A positive (glucose or mannose containing) material was analysed similarly. Similar ion exchange profiles were obtained when (3H)N-acetylglucosamine labelled mucins were studied after tissue culture of rectal biopsy specimens. No significant alteration in the ion exchange profile of purified mucins in ulcerative colitis has been shown in these studies. It is possible that the previously reported relative depletion of mucin subclass IV (eluting with 0.20 mol/l NaCl) may simply have reflected mucin depletion.
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PMID:Ion exchange chromatography of purified colonic mucus glycoproteins in inflammatory bowel disease: absence of a selective subclass defect. 195 68

Colonic glycoprotein composition was evaluated in monozygotic twins with inflammatory bowel disease using ion-exchange chromatography. Fifty-three individuals, 12 pairs and 1 single twin with ulcerative colitis and 14 pairs with Crohn's disease, were evaluated. Seven twin pairs were concordant for the presence of ulcerative colitis or Crohn's disease, whereas twin siblings of 10 ulcerative colitis probands and 9 Crohn's disease probands were not known to have inflammatory bowel disease. Content of one chromatographically defined component of colonic mucin, designated HCM species IV, was reduced in both patients with ulcerative colitis (1040 +/- 300 cpm/10,000 cpm total HCM) and their apparently healthy twins (1340 +/- 540 cpm/10,000 cpm total HCM) compared with control subjects (4030 +/- 1,000 cpm/10,000 cpm total HCM). Composition of mucin in Crohn's disease patients and their nonaffected twins was not significantly different than in controls. These observations suggest that altered profiles of mucin glycoprotein may be present before the onset of ulcerative colitis and may be genetically defined. Conversely, it appears that alterations in glycoproteins only are not sufficient to initiate mucosal inflammation.
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PMID:Colonic glycoproteins in monozygotic twins with inflammatory bowel disease. 198 38

The mucin and gland content of 26 rectal biopsy specimens--five normal specimens, 10 from patients with ulcerative colitis, and 11 from patients with Crohn's disease--were measured using a Quantimet image analyser. There was significantly less mucin in the groups with ulcerative colitis compared with either those with Crohn's disease or the normal controls. The difference in the gland content between the groups with ulcerative colitis and Crohn's disease and between the group with Crohn's disease and the normal controls did not reach significance. The results suggest that it is worth while assessing the mucin content of rectal biopsy specimens from patients with inflammatory bowel disease. In routine practice this assessment can be made by eye using a suitably stained section.
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PMID:Mucin depletion in inflammatory bowel disease. 231 90

The glycoconjugate composition of intestinal goblet cell mucin was characterized according to the anatomical distribution of lectin-binding sites in surgically resected intestinal tissues and mucosal biopsy specimens obtained from 38 control subjects, and from 32 patients with the active phase of ulcerative colitis, and 12 with Crohn's disease. Immunoperoxidase labeling studies found that in control tissues binding by Soybean Agglutinin (SBA), Dolichos Biflorus Agglutinin (DBA), Wheatgerm Agglutinin (WGA), and Ricinus Communis Agglutinin-120 (RCA-120) was consistently higher than that of Peanut Agglutinin (PNA), Ulex Europaeus Agglutinin-1 (UEA-1), Concanavalin A (ConA) and Helix Pomatia Agglutinin (HPA). Tissues from ulcerative colitis and Crohn's disease patients, showed increases in DBA and SBA binding, a reduction in HPA binding, and changes in the distribution of PNA, UEA-1, RCA-120, and HPA labeling sites. These results demonstrated that the expression of lectin-binding sites on human intestinal goblet mucin was specifically altered in ulcerative colitis and Crohn's disease, thus possibly providing another approach to the assessment of neoplastic risk on these diseases.
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PMID:Lectin histochemistry in ulcerative colitis and Crohn's disease. 276 48


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