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W Marks

Publications and source records attributed to W Marks.

26 records · Page 2Linked to original sources
PubMed1986

Immunohistochemical localization of a specific ileal peptide in the pig.

The tissue distribution of a polypeptide purified from pig ileal mucosa tentatively called porcine ileal polypeptide (PIP) and known to have potent acid secretagogue activity has been studied with immunohistochemical methods together with extraction of different tissues followed by radioimmunoassay for PIP content. Histochemically the peptide is found in superficial epithelial cells in the mucosa of the distal 20% of the small intestine and to some extent in the mucosa of the urinary tract. There is no staining of goblet cells or crypt cells. The staining in the urinary tract mucosa is due to antigenic peptides with Mr identical to PIP. While the presence of PIP in the ileum is compatible with a function as an enterooxyntin, it is not possible at present to explain the physiologic role of PIP entirely as a hormone regulating acid secretion in light of the immunohistochemical distribution.

Animals↗
PubMed1986

Characterization of circulating insulin in insulin autoimmune syndrome.

We examined the forms of circulating insulin in three patients with the insulin autoimmune syndrome by a method combining gel filtration and reverse phase high performance liquid chromatography (RP-HPLC). Insulin bound to circulating antibody was dissociated by molecular sieve chromatography at acid pH. The free insulin peak eluted from a Sephadex G-50 column was subsequently chromatographed on a Bio-Gel P-30 column. In all three patients, insulin coeluted with normal human insulin. However, when the partially purified insulins, obtained by gel filtration, were applied to RP-HPLC, an abnormally migrating insulin was found in two of three patients. The insulins were more hydrophobic than normal human, porcine, or bovine insulin, but were different from each other. A third patient had only a single insulin peak on RP-HPLC which corresponded to normal insulin. In contrast, the insulin from insulin-treated diabetic patients with antibodies to exogenous insulin corresponded to either porcine or bovine and normal human insulin. The antibodies in the circulation of these patients with the autoimmune syndrome were of the immunoglobulin G type and contained kappa and lambda-chains in the same proportions as antibodies in insulin-treated patients. Autoantibodies could not be distinguished from those secondary to exogenous insulin treatment on the basis of displacement of binding by human, beef, or pork insulin. These results suggest that in certain patients with the insulin autoimmune syndrome, there may be a molecular abnormality of circulating insulin. Whether this comprises a cause for the syndrome or is a result of posttranslational processing of insulin remains to be determined.

Adult↗
PubMed1981

Gastric adenocarcinoma: a comparison of the accuracy and economics of staging by computed tomography and surgery.

We studied a series of 22 patient with proven gastric adenocarcinoma who underwent upper gastrointestinal radiography, computed tomography, upper gastrointestinal endoscopy, and/or surgical exploration and resection. Based on the computed tomographic findings, gastric carcinoma was classified into one of four stages: stage 1, intraluminal masses without gastric wall thickening; stage 2, gastric wall thickening (> 1 cm) and exophytic masses; stage 3, gastric wall thickening and contiguous spread of tumor into adjacent organs such as the pancreas, spleen, liver, transverse mesocolon, or esophagus; and stage 4, gastric wall thickening with distant metastatic disease. The stage of gastric malignancy as determined by computed tomography was correlated with presenting symptoms, location of tumor, upper GI findings, endoscopy, and findings of surgical exploration. The cost and estimated initial saving realized by performing routine preoperative gastric computed tomographic examinations were analyzed. Our results indicated that computed tomographic staging of gastrointestinal malignancy correlated closely with surgical findings and compared with other modalities, local extension, regional adenopathy, and the size of the tumor mass were better evaluated by computed tomography. Computed tomographic staging of gastric tumors cost $7150 and resulted in an estimated initial savings of $35,000-$56,000. The results of this study indicated that computed tomography is an accurate, cost effective method of preoperatively staging gastric carcinoma, capable of providing staging information heretofore only available by surgical exploration.

Adenocarcinoma↗
PubMed1980

Computed tomography of hepatocellular carcinoma.

Computed tomography (CT) was used to evaluate 16 cases of hepatocellular carcinoma. CT identified and localized the tumor in 15 cases, an overall detection rate of 94%. The technique of dynamic CT scanning (rapid sequential scans after intravenous bolus of contrast medium), used in several cases, proved useful for determining patency of the portal vein and inferior vena cava and for demonstrating arteriovenous shunting due to tumor. CT detected some tumors missed by radionuclide scanning and arteriography. An approach to the diagnostic workup of patients with known or suspected hepatoma is presented, with a discussion of the roles of ultrasonography, radionuclide scanning, and arteriography.

Adult↗