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Biomedical subjects

V L Go

Publications and source records attributed to V L Go.

At least 199 records · Page 11Linked to original sources
PubMed1982

Laboratory diagnosis of gastrinoma. I. A prospective evaluation of gastric analysis and fasting serum gastrin levels.

In a small percentage of patients with ulcer disease, a gastrinoma may be ultimately discovered. In most institutions, a fasting serum gastrin determination and gastric analysis are as first-line tests to identify this subgroup of patients with ulcer disease. The blood test is relatively inexpensive and well accepted by patients. Gastric analysis is uncomfortable and required a well-equipped facility staffed by skilled personnel. A prospective study designed to assess the diagnostic usefulness of these tests and, particularly, whether combining both tests adds to the individual value of each, revealed that gastric analysis does not improve the diagnostic ability of the fasting serum gastrin test. Therefore, gastric analysis probably is not indicated for determining whether a patient with active ulcer disease has a gastrinoma. The fasting serum gastrin test will suffice, and abnormal values on this test should be verified by the use of other tests such as responses to gastrin provocative tests.

Adolescent↗
PubMed1981

Efforts at early diagnosis of pancreatic cancer: the Mayo Clinic Experience.

By contract with the National Cancer Institute, the authors have prospectively evaluated the diagnostic accuracy of serologic, secretory, endoscopic, and imaging procedures. Ultrasonography, computed tomography, endoscopic retrograde pancreatography, angiography, and pancreatic exocrine function tests have similar sensitivity, specificity, and predictive value in the diagnoses of pancreatic disorders. A newly developed ultrasonic endoscope has been evaluated for human use and preliminary findings suggest that it is safe. This endoscope generates a high resolution of real time images of extraluminal gastrointestinal organs, including the pancreas. This technique may be useful in detecting small premetastatic and resectable cancers of the pancreas.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1981

Exogenous gastrin in rhesus monkeys. The effect of 50% distal small-bowel resection on its rate of disappearance.

The rate of disappearance from the circulation of exogenous heptadecapeptide gastrin was studied before and after 50% distal small-bowel resection in four rhesus monkeys. For each study, venous blood samples were drawn during, and at frequent intervals after, a one-hour peripheral venous infusion of synthetic human gastrin 1 given at a constant rate within the range of 0.4 to 2.4 microgram/hr/kg of body weight. The rate of disappearance of infused gastrin was not affected by small-bowel resection (mean half-time before operation, 2.50 minutes; mean half-time after operation, 2.47 minutes). These data indicate that in the rhesus monkey, the rate of catabolism of exogenous gastrin is not decreased after distal small-bowel resection, and indicate that other mechanisms are responsible for the hypergastrinemia and gastric acid hypersecretion observed in this animal model.

Animals↗
PubMed1981

CEA (carcinoembryonic antigen): its role as a marker in the management of cancer.

A consensus Development Conference was held at the National Institutes of Health from September 29-October 1, 1980, to address issues concerning the role of carcinoembryonic antigen (CEA) as a marker in the management of cancer. The panel met following formal presentations and discussions to assess the issues based on the evidence presented. These issues included: Should CEA be used in cancer screening? Is CEA helpful in cancer diagnosis? What does CEA tell about the extent and outcome of cancer? Is CEA helpful in monitoring cancer treatment? This paper constitutes the panel's findings.

Carcinoembryonic Antigen↗
PubMed1981

Interdigestive canine pancreatic juice composition and pancreatic reflux and pancreatic sphincter anatomy.

Canine and human exocrine pancreatic secretion into the duodenum during fasting is cyclical and related to intestinal motility. To characterize the composition of pure pancreatic juice during the cyclically recurring sequence of propagated motor events (interdigestive motor complex) and to establish whether pancreatic reflux occurs, dogs were prepared with three permanent indwelling duodenal catheters and a pancreatodochal cutaneous catheter. The duodenal catheters were used to record duodenal pressures and measure pancreatic secretion of trypsin, lipase, and bicarbonate, based on the recovery of a constantly perfused marker, [14C]PEG. Pancreatic duct pressures or pancreatic juice concentrations of [14C]PEG, trypsin, lipase, or bicarbonate (done separately in each of five dogs throughout one interdigestive cycle on 4 different days) were related to duodenal motor activity. Finally, the pancreatic duct orifice of freshly sacrificed dogs was examined by light and electron microscopy. During fasting, (1) pancreatic volume secretion increased 10-fold during phases II, III, and IV (P less than 0.001), and bicarbonate concentration increased during phases III and IV (P less than 0.05) compared with phase I, while trypsin and lipase concentrations did not change; (2) reflux of duodenally perfused [14C]PEG into the pancreatic duct occurred in two of five dogs and was minimal (less than 0.1%); and (3) a positive mean pressure gradient from duodenum to pancreatic duct occurred only during phase III (7.4 +/- 4.1 cm H2O). Anatomic studies of the pancreatic duct opening showed a specialized papillary mucosa and an independent crescentic sphincter muscle. We conclude that during fasting, pancreatic juice composition is intimately linked to the different phases of interdigestive intestinal motor activity and that an efficient antireflux mechanism exists.

Animals↗
PubMed1981

Role of nutrients in the gastrointestinal release of immunoreactive neurotensin.

Neurotensin is a brain-gut tridecapeptide. It can be released into the circulation upon ingestion of a meal, or when the jejuno-ileal segment of the human gut is exposed to a mixed meal. Among the various constituents of the products of food digestion, fatty acid is the most potent in stimulating immunoreactive neurotensin release. This response is dose dependent. The physiological role of postprandial changes of circulating neurotensin needs further elucidation.

Dietary Fats↗
PubMed1981

Postprandial hormonal inhibition of canine interdigestive gastric motility.

Our aim was to determine whether hormones other than gastrin inhibit cyclic interdigestive motility in the proximal stomach. In four conscious dogs with autotransplanted proximal gastric pouches, excluded gastric antrums, and chronic duodenal electrodes, intraluminal pressure of the pouch and electrical activity of the duodenum were monitored before and after gastric instillation of 250 ml of 154 mM NaCl alone or 154 mM NaCl plus 15 kcal/kg of either dextrose, olive oil, casein hydrolysate, or a mixture containing 5 kcal/kg of each of the three nutrients. Dextrose, olive oil, casein, and the mixture abolished the interdigestive cycles in both pouch and duodenum and decreased intrapouch pressure compared with the saline control. The duration of the inhibition was longest with oil (5 h) and shortest with casein (3 h), and the decrease in mean intrapouch pressure was greatest with the mixture (11.8 cmH2O . min) and least with dextrose (9.3 cmH2O . min). Serum gastrin was unchanged by any of the instillates. We concluded that hormones other than gastrin inhibited cyclic interdigestive motility in the proximal stomach.

Animals↗
PubMed1981

A prospective study of the antisecretory and therapeutic effects of cimetidine and glucagon in human acute pancreatitis.

Nasogastric suction, glucagon, and cimetidine are proposed treatments for human acute pancreatic because they may reduce gastric acid and exocrine pancreatic secretion. However, the functional status of gastric and pancreatic secretion during human acute pancreatitis is unknown. Thus, we compared the effects of nasogastric suction, intravenous glucagon (5 microgram/kg per hour), and cimetidine (2 mg/kg per hour) on the output of acid and pancreatic enzymes and the clinical course of human acute pancreatitis. In three subjects with acute alcoholic pancreatitis, gastric acid secretion was increased above normal and was decreased by glucagon and cimetidine used alone and in combination. In two of the three patients, duodenal output of trypsin and lipase was normal or increased and was reduced by glucagon and cimetidine given alone or in combination. Twenty patients with documented acute pancreatitis randomly received treatment with nasogastric suction, cimetidine alone, or the combination of cimetidine and glucagon. Four of the five complications observed during the trial occurred in the combination-treatment group (P less than 0.05). Administration of cimetidine alone or with glucagon did not improve the outcome when compared with nasogastric suction.

Acute Disease↗
PubMed1981

Decreased bioavailability of prednisone due to antacids in patients with chronic active liver disease and in healthy volunteers.

To investigate the potential action of antacids on prednisone absorption and on prednisolone serum levels, we studied 5 healthy volunteers and 12 patients with chronic active liver disease. Six patients responded to treatment and 6 did not. After administering two 5-mg tablets of prednisone with 60 ml of water, 60 ml of Melox (AlOH 3.75 g/100 ml + MgOH 4.0 g/100 ml), or 60 ml of Aldrox (AlOH 8.0 g/100 ml + MgOH 1.95 g/100 ml), we measured prednisolone by radioimmunoassay. Both peak heights and areas under the serum-concentration curves were significantly reduced when prednisone was administered with antacids. The relative bioavailability of prednisone after prednisone-antacid treatments compared to that after prednisone-water treatment was 74% +/- 13% (p less than 0.05) with Melox and 57% +/- 15% (p less than 0.01) with Aldrox in healthy volunteers. In patients with chronic active liver disease responding to treatment, prednisone bioavailability was 65% +/- 120% (p less than 0.01) and 87% +/- 20%, respectively. Among patients with chronic active liver disease not responding to treatment, this parameter was 76% +/- 12% (p less than 0.05) and 80% +/- 21% (p less than 0.05), respectively. To insure adequate prednisolone levels in patients with chronic active liver disease, prednisone should not be given simultaneously with antacids.

Adult↗
PubMed1981

Intestinal control of human postprandial gastric function: the role of components of jejunoileal chyme in regulating gastric secretion and gastric emptying.

Intestinal control of gastric secretion and emptying were studied in healthy humans by using intubation-marker-perfusion techniques. An occluding balloon was used to separate the jejunoileal test segment from the more proximal gut. Mixed-nutrient, semielemental meals (300 and 600 calories) were administered while varying the jejunal perfusate: normal saline, jejunal chyme or its protein (casein hydrolysate), lipid (oleic acid), or carbohydrate (maltose) components. The meal in contact with the stomach and duodenum increased gastric secretion above fasting levels. This was partially inhibited by whole chyme in contact with the jejunum, the lipid and carbohydrate components of chyme mediating this inhibition. Jejunoileal chyme inhibited gastric emptying, with all three nutrient components acting as inhibitors. Effects on gastric secretion and emptying were dose-dependent, being greater after the larger meal and most prominent in the early postprandial period; these effects on gastric emptying were more prominent than those on gastric secretion. These results suggest that the intestinal phase of gastric function is directed mainly toward regulation of the reservoir function of the stomach: to adapt the gastric delivery of nutrients and fluid to the capability for efficient digestion and absorption.

Adult↗
PubMed1981

The nature and prognostic significance of serial amino acid determinations in severe chronic active liver disease.

Serum amino acid levels were determined in 29 patients with severe chronic active liver disease before, during, and after administration of prednisone or placebo and in 22 healthy controls. The pretreatment molar ratio of amino acids was less in patients than in controls (p less than 0.001) and was lower in those with cirrhosis (p less than 0.02). Branched-chain amino acid levels were elevated in patients without cirrhosis (p less than 0.02) but not in those with cirrhosis; aromatic amino acid concentrations were increased in all (p less than 0.01). The ratio improved with remission and predicted behavior after discontinuation of treatment. Patients who deteriorated failed to improve the ratio and those whose ratio improved incompletely relapsed. The ratio correlated with histologic severity and serum concentrations of albumin, bilirubin, and gamma-globulin and not with clinical manifestations of encephalopathy. We conclude that amino acid abnormalities reflect liver dysfunction and that normalization of the molar ratio may have therapeutic and prognostic significance.

Adolescent↗
PubMed1981

Increased activity in serum of an alkaline phosphatase isoenzyme in cancer: analytical method and preliminary clinical studies.

Serum of cancer patients often contains high activities of a homoarginine-sensitive isoenzyme of alkaline phosphatase with high electrophoretic mobility, which is present in relatively low activities in sera from most normal persons and persons with benign disease. In earlier studies of this isoenzyme, in a semi-quantitative assay, electrophoresis was used in the separation step. This report describes a column separation procedure, which provides quantitative data. We tested the revised procedure by assaying a mixed panel of 192 sera (cancer, benign disease, and normal). The organ sites of cancer and benign disease in this study were: lung, pancreas, uterus, and ovaries. The isoenzyme showed moderate sensitivity for lung (0.6) and pancreas (0.8) cancer and high specificity for all cancers tested. Thus the assay may be useful for discriminating between cancer sera and non-cancer sera for these cancer types.

Adult↗
PubMed1980

Are elevated pancreatic polypeptide levels in patients with insulinoma secondary to hypoglycaemia?

In 13 patients with insulinoma, human pancreatic polypeptide (hPP) was measured under basal conditions, after a mixed meal, and during a fast of up to 72 h. Significant negative correlatons between hPP and plasma-glucose levels were found both under basal conditions and during fasting. Patients with insulinoma and basal plasma-glucose values above 60 mg/dl had hPP values similar to those in control subjects, whereas insulinoma patients with plasma-glucose values under 60 mg/dl had significantly higher hPP values (323 versus 115 pg/ml). The mean hPP response to a mixed meal was similar in patients with insulinoma and in control subjects. hPP values during symptomatic hypoglycaemia were higher in insulinoma patients than controls fasted for comparable times (751 versus 171 pg/ml). Under conditions of euglycaemia, hPP is not a reliable marker for insulinoma.

Adenoma, Islet Cell↗
PubMed1980

Prospective evaluation of some candidate tumor markers in the diagnosis of pancreatic cancer.

As part of a prospective diagnostic protocol, patients suspected of having pancreatic cancer had systemic and portal venous blood samples assayed, in coded batches, for peptide hormones and enzymes thought to be of potential value as tumor markers. An average of 111 patients were tested for each candidate marker. Results were analyzed by dividing patients into three groups according to the definitive diagnoses. These were pancreatic cancer (32% of patients), other cancers (27%), and benign diseases (41%). Although elevated mean levels of fasting plasma glucose and serum alkaline phosphatase were found in the pancreatic cancer group, there were no significant differences in the mean levels of any of the candidate markers studied in the three groups. The diagnostic values of normal and elevated levels of each candidate marker studied have been calculated. None has proven to be as useful as the serum level of pancreatic oncofetal antigen, fasting plasma glucose, or serum alkaline phosphatase in the diagnosis or exclusion of pancreatic cancer.

Alkaline Phosphatase↗
PubMed1980

Dysfunctions of the stomach with gastric ulceration.

Factors implicated in the pathogenesis of gastric ulcer were studied simultaneously in seven patients with strictly defined type 1 gastric ulcer (single benign ulcer above the incisura of the stomach) and in six healthy controls. After ingestion of an ordinary solid-liquid meal, patients with gastric ulcer demonstrated gastric hyposecretion of acid, pepsin, and water; delayed gastric emptying of solids with normal emptying of liquids; and increased intragastric concentrations of bile acids. These functional abnormalities appear to be interrelated. Metoclopramide, administered orally in a double-blind fashion, ameliorated the defect in the emptying of solids and the high concentrations of bile acid in the gastric contents. The ability of this drug to break this interdependent cycle suggests the need for further clinical investigation.

Achlorhydria↗
PubMed1980

Familial pheochromocytoma and islet cell tumor of the pancreas.

The occurrence of pheochromocytoma(s) or pancreatic islet cell tumor(s), or both, in two or more members of three unrelated families in a manner consistent with autosomal dominant inheritance suggests that this tumor association is a genetically determined syndrome. Among 11 affected patients (aged five to 53 years), 10 had pheochromocytoma (bilateral in six), four had islet cell tumor (multicentric in one), and three had both tumors. Clinical presentation was due to pheochromocytoma in 10 cases (symptoms or signs commencing before age 10 years in three patients) and islet cell carcinoma in one case. Four patients are dead as a result of the tumors--two from pheochromocytoma and two from islet cell carcinoma.

Adenoma, Islet Cell↗