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Biomedical subjects

C K Montgomery

Publications and source records attributed to C K Montgomery.

At least 19 recordsLinked to original sources
PubMed1996

Altered mucin core peptide immunoreactivity in the colon polyp-carcinoma sequence.

Altered mucin glycosylation occurs in colonic adenomas and can correlate with risk for malignant transformation. The purpose of this study was to determine if immunoreactivity of core tandem repeat peptides of specific mucin genes correlates with histopathologic criteria of malignant potential in the colon. Expression of MUC1, MUC2, and MUC3 core tandem repeat proteins was examined in specimens of normal mucosa (n = 20), hyperplastic polyps (n = 10), adenomatous polyps (n = 89), and invasive cancer (n = 19). An immunohistochemical scoring system that takes into account specimen heterogeneity and yields an integrated numerical score subject to statistical analysis was used. RNA message levels from tubular and tubulovillous adenomas (n = 13), normal colon (n = 12), and moderately differentiated adenocarcinomas (n = 8) were determined using RNA slot blot analysis with mucin-specific cDNA probes. MUC1 staining was rarely present in normal colon. MUC2 immunoreactivity was limited to goblet cells in most normal colonic crypts, and MUC3 staining was weakly expressed in the upper crypt regions only. In comparison with normal and hyperplastic specimens, MUC1 and MUC3 immunoreactivity scores were significantly increased in adenomas of increasing villous histology, size, and dysplasia. MUC2 scores were significantly increased in adenomas of greater villous histology and size. Comparable MUC1, MUC2, and MUC3 mRNA levels were present in adenomas and normal colon, whereas mucin mRNA levels were decreased in adenocarcinomas. We conclude that enhanced immunoreactivity of MUC1, MUC2 and MUC3 mucin tandem repeats occurs in adenomatous polyps and is associated with an increased risk for malignant transformation.

Adenoma, Villous↗
PubMed1990

Cell lineage markers in human pancreatic cancer.

The normal pancreas consists of three major cell types or lineages that share a common embryologic origin from pluripotent endodermal precursors. The type of cell that undergoes neoplastic transformation to form a pancreatic carcinoma is controversial and may influence the phenotype and biologic behavior of the tumor. In this study, immunohistologic techniques were used to determine the cell lineage differentiation expressed in 29 primary exocrine pancreatic adenocarcinomas, five metastatic exocrine pancreatic adenocarcinomas, and five islet cell neoplasma. Specimens of normal pancreas and chronic pancreatitis were used for comparison. The cell lineage markers consisted of monoclonal and polyclonal antibodies against trypsin and lipase (acinar cells); secretory component, carbonic anhydrase II, and pancreatic cancer mucin SPan-1 (ductal cells); and chromogranin-A and somatostatin (islet cells). The expression of carcinoembryonic antigen (CEA) and lysozyme were also determined. This collection of markers allowed the differentiation between acinar, ductal, and islet cells of normal pancreas and chronic pancreatitis specimens. The expression of cell lineage markers in islet cell tumors was homogeneous and restricted to chromogranin-A. In contrast, the expression of these markers in primary and metastatic exocrine pancreatic adenocarcinomas was variable. Reactivity with monoclonal anti-CEA was absent in normal pancreas, and was present in 83% of chronic pancreatitis specimens as well as 90% of exocrine pancreatic adenocarcinomas. In addition, lysozyme reactivity was absent in normal pancreas; however, lysozyme was expressed in one case of chronic pancreatitis, 17 cases of primary carcinoma, and three cases of metastatic carcinoma. These findings support the concept that the original transformed cell type in many pancreatic exocrine carcinomas resemble endodermal "stem cells" that retain the capability of differentiation along more than one cell lineage pathway.

Biomarkers↗
PubMed1989

Expression of Tn, sialosyl-Tn, and T antigens in human colon cancer.

Mucin glycoproteins are major secretory products of the colon and contain O-linked oligosaccharides synthesized on a polypeptide backbone. The initial step in the synthesis of O-linked oligosaccharides is the addition of N-acetylgalactosamine to serine or threonine residues forming the Tn antigen. This substance can then receive additional carbohydrate residues such as sialic acid to form sialosyl-Tn antigen, or galactose to form T antigen. In the colon, the T antigen is an oncodevelopmental cancer-associated antigen but little is known about Tn and sialosyl-Tn expression. The present comparative immunohistochemical study was performed to analyze the expression of these antigens in fetal, normal adult, and malignant colorectal tissues with an aim toward elucidating whether Tn and sialosyl-Tn are also oncodevelopmental colon cancer-associated antigens and to gain insight into the earliest steps of mucin glycosylation in colonocytes. We used three reagents to detect Tn antigen (two monoclonal antibodies ETn1.01 and CU-1, and one lectin Vicia villosa), two reagents to detect sialosyl-Tn (monoclonal antibodies TKH2 and B72.3) and one to detect T antigen (monoclonal antibody AH9-16). Except for occasional reactivity with VVA and CU-1, cells of normal colonic mucosa did not express Tn, sialosyl-Tn, or T antigens. However, in the transitional mucosa immediately adjacent to cancer, all three antigens were expressed (ranging from 35 to 67% of cases depending upon the reagent). In colon cancers, the percentage of cases expressing each antigen were as follows: Tn 72-81%, sialosyl-Tn 93-96%, and T 71%. Unlike T antigen, which was preferentially expressed by moderately well- and well-differentiated adenocarcinomas, both Tn and sialosyl-Tn antigens were expressed by most histological subsets of colon cancers, including poorly differentiated adenocarcinomas and mucinous (colloid and signet ring cell type) carcinomas. The majority of cancers expressed both Tn and sialosyl-Tn, usually in association with T antigen. Only one cancer lacked all three antigens. Fetal colonic mucosal cells expressed all three antigens, particularly in goblet cell mucin. These results indicate that like T antigen, Tn and sialosyl-Tn are oncodevelopmental cancer-associated antigens in the colon. Moreover, Tn and sialosyl-Tn antigens appear to be useful markers of poorly differentiated adenocarcinomas and mucinous carcinomas: two histological subsets that often fail to express other cancer-associated antigens and that are often associated with a poor clinical outcome.(ABSTRACT TRUNCATED AT 400 WORDS)

Antibodies, Monoclonal↗
PubMed1987

Phlegmonous gastritis and Hemophilus influenzae peritonitis in a patient with alcoholic liver disease.

A patient with alcoholic liver disease and ascites had Haemophilus influenzae peritonitis and died in spite of vigorous antibiotic therapy. At autopsy, a phlegmonous gastritis was found as a likely cause of the peritonitis. Phlegmonous gastritis is an uncommon cause of unexplained gastrointestinal symptoms in alcoholics and in the elderly, and it may be pathogenetic in rare patients with bacterial peritonitis of unclear source.

Cellulitis↗
PubMed1986

Collagen tubes: role in subperiosteal contour augmentation.

Collagen-contained implants of particulate hydroxylapatite (C-HA) were compared to implants of hydroxylapatite alone (HA). The collagen-contained implant was more rapidly and more firmly attached to the recipient site and demonstrated more consistent particle consolidation than implants of HA alone. Additionally, the collagen did not interfere with the favorable properties of the particulate hydroxylapatite. Results are excellent for the (C-HA) implant and warrant further investigation in both animals and in man.

Animals↗
PubMed1985

Electron microscopic demonstration of lysosomal inclusion bodies in lung, liver, lymph nodes, and blood leukocytes of patients with amiodarone pulmonary toxicity.

The mechanism of amiodarone-induced pulmonary toxicity is unknown. Two cases of amiodarone pulmonary toxicity are presented in which abnormal inclusion bodies containing whorls of membrane were seen on electron microscopy of extrapulmonary tissues. These cytoplasmic lysosomal inclusion bodies were observed in lymphocytes, plasma cells, granulocytes, tissue macrophages, and hepatocytes. These widespread histopathologic changes in extrapulmonary tissues and in a variety of cell types are similar to more extensively investigated findings in animal models that are thought to represent a drug-induced lysosomal storage disease, phospholipidosis.

Amiodarone↗
PubMed1985

Parathyroid aspiration biopsy under ultrasound guidance in the postoperative hyperparathyroid patient.

A 10-MHz high-resolution dedicated small parts scanner and a static 5-MHz digital scanner were used in the ultrasound (US) examination of 11 patients with hyperparathyroidism who had previously undergone surgery of the parathyroid (eight patients) or thyroid (three patients) gland. Using US localization, aspiration biopsies were performed successfully in nine patients: parathyroid disease was confirmed in seven patients and thyroid lesions in two. Inadequate aspirate was obtained in one patient; in another patient a biopsy was done successfully under CT guidance following a negative US examination. The authors conclude that high-resolution US is an effective tool for guiding the aspiration biopsy of nonpalpable parathyroid tumors in patients who have had neck surgery. They suggest modifications of the US equipment that would simplify the localization procedure.

Adenoma↗
PubMed1983

Detection of hepatitis B virus DNA in hepatocytes, bile duct epithelium, and vascular elements by in situ hybridization.

A radiolabeled probe specific for hepatitis B virus (HBV) nucleotide sequences was hybridized in situ to liver tissue from three patients with chronic hepatitis B. The HBV genome was detected not only in infected hepatocytes but also in bile duct epithelial cells, endothelial cells, and smooth muscle cells. These findings extend the known host cell range for HBV, suggest new mechanisms of viral dissemination, and illustrate the usefulness of in situ hybridization in the study of pathogenesis of HBV infection.

Animals↗
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↗
PubMed1982

Postinflammatory polyposis (PIP) of the colon: the radiologic-pathologic spectrum.

The radiologic-pathologic spectrum of postinflammatory polyposis (PIP) of the colon and the evolution of the radiographic appearance of PIP over time were retrospectively studied in 27 patients (21 with ulcerative colitis, 6 with Crohn disease). Two general patterns of radiographic evolution were recognized: progression from active, ulcerating disease to mucosal healing with formation of PIP, and interruption of healing with PIP by recrudescence of active ulceration with inflammatory pseudopolyposis. In these latter cases, disease activity recurred in the same areas in which healing with PIP had been recognized. A review of all pathologic material indicated that the histopathology of PIP is varied and depends, to a large extent, on polyp size.

Adult↗
PubMed1979

Colitis in the elderly: ischemic colitis mimicking ulcerative and granulomatous colitis.

Eight patients over age 60 years had sudden onset of acute abdominal pain and rectal bleeding in the absence of prior inflammatory bowel disease. Several improved on medical therapy alone; those who required surgery suffered no recurrence up to 6 years. Although the pathologic specimens on these patients were first considered to represent ulcerative colitis or Crohn's disease, their histories and clinical courses are much more consistent with ischemic colitis. Since there are only a limited number of reactions that the bowel can muster against a host of damaging processes, histologic criteria alone are usually not sufficient to separate ischemic disease of the colon from ulcerative colitis and Crohn's disease. This is also true of radiographic features. Thus the diagnosis of ischemic colitis rests on clinical onset and course after treatment.

Aged↗
PubMed1977

Invasion of the duodenum by carcinoma of the stomach.

It has frequently been stated that extension to the duodenum occurs commonly in patients with gastric lymphoma but almost never in those with carcinoma of the stomach. We found radiographically detectable invasion of the duodenum in six of 111 consecutive patients (5%) with gastric carcinoma. The duodenum was involved microscopically in 18%. Radiographic abnormalities in the duodenum in 11 patients with proven transpyloric spread of tumor varied from irregularity of the base of the bulb narrowing and distortion extending well into the second portion of the duodenum. On the basis of these data and the reported frequency of transpyloric extension in gastric lymphoma, carcinoma appears to be the more likely diagnosis in a patient with duodenal involvement by an antral tumor.

Adenocarcinoma↗