Search PubMed⌕ Search

Biomedical subjects

C R Boland

Publications and source records attributed to C R Boland.

98 records · Page 6Linked to original sources
PubMed1984

Abnormal goblet cell glycoconjugates in rectal biopsies associated with an increased risk of neoplasia in patients with ulcerative colitis: early results of a prospective study.

A group of 18 patients with stable ulcerative colitis involving the entire colon for at least eight years was subjected to a biopsy of normal appearing rectal mucosa and followed prospectively over four years for the development of either dysplasia or cancer. Goblet cell glycoconjugate structure was examined in the rectal biopsies using fluorescein conjugated lectins. At the beginning of the study, 13 of the 18 patients had abnormalities of goblet cell mucin or cytoplasmic glycoconjugates in the rectal biopsies. Dysplasia subsequently developed in six and carcinoma in one of these patients. Among the five patients with normal lectin binding studies in the initial rectal biopsies, colonic dysplasia has subsequently developed in one. The abnormalities seen in the rectal goblet cells resembled in part those previously seen in immature and neoplastic colonic cells. The dysplastic tissues all contained the form of mucin which has been found in other neoplastic colonic tissues. This preliminary report after four years of prospective study suggests that abnormalities of glycoconjugate structure may be associated with, and may precede, neoplastic events in the setting of chronic ulcerative colitis.

Colitis, Ulcerative↗
PubMed1984

Characteristics of colorectal carcinoma cells with high metastatic potential.

Malignant tumors shed large numbers of cells into the circulation, only a small fraction of which actually produce distant metastases. The cells comprising these tumors may be heterogeneous in many respects including their biological behavior. Inasmuch as colonic epithelial cells secrete mucins that reflect the state of cell differentiation, and differences in mucin structure may be detected by selective lectin binding, we used fluorescein isothiocyanate-conjugated lectins and fluorescence microscopy to analyze mucins secreted by primary colon cancers and metastases. In this way we hoped to determine whether differences exist in the glycoconjugates produced by metastatic and nonmetastatic cell populations. Out studies demonstrated that, in a given primary cancer, the mucin produced differed from that made by its metastases. Thus the vast majority of cells in primary tumors produced mucin that was specifically labeled by fluorescent peanut agglutinin (14 of 16 tumors). In contrast, 72% (37 of 51) of metastatic tumors produced mucin that did not bind peanut agglutinin (p less than 0.001). Colon cancer cells with high metastatic potential may therefore produce mucins that lack an exposed oligosaccharide receptor for this lectin.

Arachis↗
PubMed1982

Alterations in human colonic mucin occurring with cellular differentiation and malignant transformation.

The binding of fluorescein isothiocyanate (FITC)-conjugated lectins to mucin in the human colon was studied by using fluorescence microscopy. In normal mucosa, lectins that preferentially bind to exposed N-acetyl-galactosamine residues (Dolichos biflorus agglutinin and soybean agglutinin) bound selectively to the goblet cell mucin of well-differentiated cells in the upper colonic crypt. By contrast, lectins that require exposed non-reducing galactose residues for binding (Ricinus communis agglutinin1 and Bauhinia purpurea agglutinin) preferentially labeled the mucin of less-differentiated goblet cells located in the lower portion of the colonic crypt. The lectin derived from Arachis hypogaea (peanut agglutinin) has a high affinity for a carbohydrate structure not normally exposed in human tissues. This lectin did not label the goblet cell mucin in the normal colon. However, the mucin was labeled in all 21 colon cancer specimens examined. Additionally, the nonmalignant epithelium immediately adjacent to colon cancer (termed "transitional mucosa") also contained goblet cell mucin that was labeled by FITC-peanut agglutinin. Three conclusions may be drawn from the selective binding characteristics of FITC-lectins to colonic mucins. First, an alteration in the exposed, nonreducing carbohydrate residues occurs in human colonic mucin during the process of goblet cell differentiation. Second, an exposed carbohydrate structure that is not normally present in human tissues is expressed in the mucin produced by malignant colonic epithelium. Third, the presence of the cancer-associated carbohydrate structure in the mucin of transitional mucosa suggests that this tissue may be in the process of early malignant transformation.

Cell Differentiation↗
PubMed1980

Liquid caustic ingestion. Spectrum of injury.

Seventeen patients who ingested liquid caustics were reviewed for location, extent, severity, and outcome of the mucosal injury. Although many complained of glossopharyngeal pains and dysphagia (12 patients), and most had some oral mucosal burns (15 patients), the absence of severe oral burns or pharyngoesophageal symptoms did not exclude esophageal or gastric injury as determined by endoscopy. The location of the most severe mucosal injury was unpredictable by symptoms alone; seven of the 17 patients demonstrated gastric mucosal injury greater than esophageal. One patient died of extensive esophageal, gastric, and duodenal injury; esophageal strictures developed in three patients. Caustic ingestion is a serious medical condition whose severity can best be gauged by endoscopic findings and not by patient symptoms alone. Outcome is variable, ranging from an asymptomatic state to stricture formation or even death.

Adolescent↗