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S R Wise

Publications and source records attributed to S R Wise.

4 recordsLinked to original sources
PubMed1990

Hyperparathyroidism and cellular mechanisms of gastric acid secretion.

Patients with hyperparathyroidism appear to be a particular risk for peptic ulcer disease. To test the hypothesis that hypercalcemia or parathyroid hormone plays a role in promoting ulcer disease, we studied the effect of varying concentrations of extracellular calcium on acid secretion using in vitro isolated rabbit gastric glands. Acid secretion was assessed by the accumulation of carbon 14-labeled aminopyrine (14C-AP). Glands were incubated with varying calcium concentrations in the unstimulated state and with histamine or carbachol (10(-7) to 10(-4) mol/L) in 1 or 2 mmol/L calcium medium. The effect of parathyroid hormone was also examined under identical conditions. Compared to 1 mmol/L standard calcium medium, unstimulated 14C-AP accumulation was significantly inhibited (p less than 0.05) at both lower (0.33 mmol/L) and higher (2 and 2.5 mmol/L) calcium concentrations. Accumulation of 14C-AP in response to histamine stimulation was unaffected by alteration of extracellular calcium (p greater than 0.2). Carbachol-stimulated 14C-AP accumulation was significantly augmented (p less than 0.01) by an increase in calcium concentration from 1 to 2 mmol/L. The addition of parathyroid hormone (10(-7) to 10(-4) mmol/L) alone or in combination with carbachol or histamine (10(-6) mmol/L) incubation did not alter 14C-AP accumulation. These data suggest that elevations in extracellular calcium play an active role in the potentiation of cholinergic-mediated gastric gland acid secretion and may thereby play a role in hyperparathyroid-related ulcer disease.

Aminopyrine↗
PubMed1989

Gastrinoma: the predictive value of preoperative localization.

In the management of gastrinoma, a variety of preoperative tests for tumor localization are recommended. Their value in predicting surgical outcome is not well defined. We reviewed the preoperative investigation and operative outcome in 23 patients to assess the predictive value of localization before surgery. With results of laparotomy used as reference, the efficacy of computed tomography, angiography, ultrasonography, and magnetic resonance imaging, individually and combined for primary and metastatic disease, was determined. All investigative modalities were poor for the detection of primary gastrinomas, with individual sensitivities in the range of 20% to 29%. Their combined sensitivity was 53%, with a negative predictive value of only 38%. The detection of metastatic disease was better, with a combined accuracy of 83%. At laparotomy, tumor was identified in 19 of 23 (83%) patients. In 14 patients with negative preoperative workup, primary gastrinoma was found in 10 of 14 (71%) and resected for long-term cure in three of 14 (21%) patients. In all nine patients with positive preoperative test results, tumor was found and was resected for cure in four (44%) patients. In conclusion, preoperative localization of primary gastrinoma is unreliable, and a negative workup does not preclude cure. Therefore, despite the availability of effective palliative antiulcer therapy, all patients exclusive of those with multiple endocrine neoplasia, type I, or metastasis should undergo laparatomy with curative resection in mind.

Angiography↗