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Dive into the research topics where Ian G. Renner is active.

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Featured researches published by Ian G. Renner.


Digestive Diseases and Sciences | 1985

Death due to acute pancreatitis. A retrospective analysis of 405 autopsy cases.

Ian G. Renner; William T. SavageIII; Jose L. Pantoja; V. Jayne Renner

A large retrospective autopsy study of patients was analyzed to evaluate the major etiologic and pathologic factors contributing to fatal acute pancreatitis (AP). From an autopsy population of 50,227 patients, 405 cases were identified where AP was defined as the official primary cause of death. AP was classified according to morphological and histological, but not biochemical, criteria. Patients with AP died significantly earlier than a control autopsy population of 38,259 patients. Sixty percent of the AP patients died within 7 days of admisssion. Pulmonary edema and congestion were significantly more prevalent in this group, as was the presence of hemorrhagic pancreatitis. In the remaining 40% of patients surviving longer than 7 days, infection was the major factor contributing to death. Major etiologic groups in AP were chronic alcoholism; postabdominal surgery; common duct stones; a small miscellaneous group including viral hepatitis, drug, and postpartum cases; and a large idiopathic group comprising patients with cholelithiasis, diabetes mellitus, and ischemia. The prevalence of established diabetes mellitus in the AP group was significantly higher than that observed in the autopsy control series, suggesting that this disease should be considered as an additional risk factor influencing survival in AP. Pulmonary complications, including pulmonary edema and congestion, appeared to be the most significant factor contributing to death and occurred even in those cases where the pancreatic damage appeared to be only moderate in extent. Emphasis placed on the early recognition and treatment of pulmonary edema in all cases of moderate and severe AP should contribute significantly to an increase in survival in this disease.


Annals of Internal Medicine | 1984

Double-contrast barium meal and upper gastrointestinal endoscopy. A comparative study.

Cornelius P. Dooley; Alan W. Larson; Nigel H. Stace; Ian G. Renner; Jorge E. Valenzuela; Joan Eliasoph; Patrick M. Colletti; James M. Halls; John M. Weiner

One hundred randomly selected inpatients were examined with both double-contrast barium meal and endoscopy in a blinded prospective fashion. All studies were done by staff personnel, with equal clinical information available to both the radiologist and endoscopist. The final diagnosis was made by a review committee of participating radiologists and endoscopists. Endoscopy was more sensitive (92% versus 54%, p less than 0.001) and specific (100% versus 91%, p less than 0.05) than the double-contrast barium meal. Both procedures significantly affected the clinical outcome of the patient, the effect of endoscopy being significantly greater than that of the double-contrast barium meal. Although errors with the barium study related predominantly to an inability to show subtle lesions, poor patient cooperation and perceptual and technical failures were additional significant factors. Endoscopy is recommended for certain groups of patients.


Gastroenterology | 1988

Effects of L-364,718, a New Cholecystokinin Receptor Antagonist, on Camostate-Induced Growth of the Rat Pancreas

James R. Wisner; Ruth E. McLaughlin; Kathryn A. Rich; Susumu Ozawa; Ian G. Renner

Chronic feeding of rats with camostate results in pancreatic hypertrophy or hyperplasia, or both. Previous studies suggest that this effect of camostate occurs via an increase in endogenous cholecystokinin due to an enteral feedback mechanism involving the inhibition of trypsin in the duodenum. Studies employing proglumide, a weak and relatively nonspecific cholecystokinin antagonist, have failed to fully abolish camostate-induced pancreas growth. We examined the effects of L-364,718, a new and highly potent cholecystokinin receptor antagonist, on camostate-induced pancreas growth in rats. The pancreas weights and the concentrations of ribonucleic acid, protein, and chymotrypsinogen in the pancreas of rats treated with camostate alone were significantly elevated over those of controls. These effects of camostate were completely abolished in rats treated with camostate + L-364,718. The pancreas weights and the concentrations of deoxyribonucleic acid and ribonucleic acid in the pancreas of rats treated with L-364,718 alone were significantly lower than values in control rats. These data indicate that camostate-induced pancreas growth in rats appears to be dependent on the actions of endogenous cholecystokinin and that cholecystokinin may play a role in the maintenance of pancreatic growth in normal rats.


Scandinavian Journal of Gastroenterology | 1980

Studies of Pure Pancreatic Secretions in Chronic Alcoholic Subjects without Pancreatic Insufficiency

Ian G. Renner; H. Rinderknecht; Jorge E. Valenzuela; Adrian P. Douglas

To determine the role alcohol might play in altering pancreatic function, we have examined pure pancreatic juice, obtained by endoscopic cannulation of the pancreatic duct, from a group of 10 chronic alcoholic subjects without history or clinical or laboratory evidence of pancreatic disease and compared the results with those obtained from 15 healthy, non-alcoholic subjects. These findings confirm observations in experimental animals made by others and support the hypothesis that chronic alcohol abuse may damage the pancreas via a sequence of events involving protein hypersecretion. Increase in concentration was not uniform for all proteins measured. Unexpectedly, chronic alcoholics exhibited a highly significant elevation (two- to three-fold over normal) in trypsinogen, in contrast to statistically insignificant increases of other zymogens and trypsin inhibitor. The strikingly increased ratio of trypsinogen to trypsin inhibitor observed in all our alcoholic patients may indicate a weakening of the defence mechanism provided by the trypsin inhibitor against premature intraductal activation of zymogens and explain the predisposition of these patients to pancreatitis.


Pancreas | 1987

Gabexate mesilate (FOY) protects against ceruletide-induced acute pancreatitis in the rat

James R. Wisner; Ian G. Renner; James H. Grendell; Claus Niederau; Linda D. Ferrell

Acute pancreatitis (AP) is believed to result from intraparenchymal activation of trypsin and other digestive enzymes within the pancreas followed by autodigestion of the gland. Gabexate mesilate (FOY), a synthetic guanidino acid ester exhibiting potent and versatile inhibitory actions on a number of proteinases (e.g., trypsin, kallikrein, C1&OV0401;, C1 esterase, plasmin, thrombin, phospholipase A2), was examined for its ability to protect the rat pancreas against development of AP induced by pharmacological doses of ceruletide (CRT). Rats were i.v. infused for 6 h with either CRT (5 μg/kg/h) or CRT + FOY (50 mg/kg/h). In FOY-treated rats the serum amylase and trypsinogen concentrations were reduced by 60 and 80%, respectively, compared to rats infused with CRT alone. Histologically, the extent of acinar cell vacuolization in the pancreas was significantly reduced and interstitial edema, although not assessed by quantitative morphometric techniques, appeared to be qualitatively lessened in the FOY-treated rats. The ability of FOY to inhibit significantly AP produced by supramaximal doses of CRT, coupled with its inhibitory properties on components of the coagulation and complement cascades, stress the importance of continued research on this compound as a potential therapeutic agent for treatment of AP and its systemic sequelae.


Digestive Diseases and Sciences | 1983

Pancreatic secretion after secretin and cholecystokinin stimulation in chronic alcoholics with and without cirrhosis

Ian G. Renner; H. Rinderknecht; James R. Wisner

We have studied the volume, protein concentration, total protein, and chymotrypsin and trypsin outputs in pure pancreatic juice (PPJ) following endoscopic cannulation of the pancreatic duct in 11 male and 2 female patients with advanced alcoholic cirrhosis (AC). Results were compared to those obtained from 21 nonalcoholic volunteers (NAV) and 26 chronic alcoholic (CA) patients without cirrhosis. Intravenous stimulation with secretin followed 10 min later by intravenous cholecystokinin-pancreozymin (CCK-PZ) resulted in highly significant increases in volumes during both phases of pancreatic stimulation in AC compared to NAV and CA. Protein concentration and total output during secretin stimulation was not different among the three groups. During CCK-PZ stimulation, CA exhibited a significant elevation in protein concentration and total output compared to NAV and AC. Although total chymotrypsin output was lower in secretin-stimulated CA than other groups, no other differences between the groups were observed in either of the hormone-stimulation phases. Marked elevations in trypsin output were observed in secretin-stimulated AC and in CCK-PZ-stimulated AC and CA. The high PPJ volume and the relatively low protein concentration observed in AC may effect a washout phenomenon resulting in a decreased tendency for ductal protein precipitation in these patients.


Digestive Diseases and Sciences | 1986

Partial restoration of pancreatic function by exogenous secretin in rats with ceruletide-induced acute pancreatitis

Ian G. Renner; R James WisnerJr.; Bradford C. Lavigne

Pharmacological doses of ceruletide administered intravenously to unconscious rats uniformly induces acute pancreatitis (AP) as well as a striking reduction in pure pancreatic juice (PPJ) and protein output. High-dose intravenous secretin administered to rats with ceruletide-induced AP effects a reestablishment of PPJ flow and a significant increase in PPJ protein output. Light microscopy of the pancreas in ceruletide-induced AP rats revealed marked acinar cell vacuolization and intense interstitial edema. By contrast, pancreatic histology in AP rats treated with high-dose secretin revealed a distinct lessening of acinar cell vacuolization and interstitial edema. We have established that high-dose intravenous secretin given to rats with ceruletide-induced AP is (1) not harmful, (2) reestablishes PPJ flow and evokes a partial restoration of protein output, and (3) appears to reduce pancreatic histopathology when compared to non-secretin-treated rats with AP.


Digestive Diseases and Sciences | 1983

Production of acute hemorrhagic pancreatitis in the dog using venom of the scorpion,Buthus quinquestriatus

Jose L. Pantoja; Ian G. Renner; Stephan B. Abramson; Hugh A. Edmondson

Acute hemorrhagic pancreatitis has been produced in dogs by two separate intraarterial injections (20 and 10 μg/kg) of venom from the scorpionButhus quinquestriatus. Morphological changes related to the development of the disease were detectable by electron and light microscopy at 1 and 3 hr, respectively, following the injection of venom. Six hours following venom injection, widespread areas of hemorrhage and fat necrosis were observed on the surface of the pancreas and adjacent mesenteries. By 24 hr, areas of fat necrosis more than 1 cm in diameter were present on the surface of the pancreas. No free protease was found in pure pancreatic juice collected at 3, 6, 24, and 96 hr after the injection ofButhus quinquestriatus venom. Amylase concentrations in serum increased to a maximum sevenfold above the basal level at 6–8 hr after injection. Since acute hemorrhagic pancreatitis occurred both with and without pancreatic duct cannulation, it is likely that the pathological process is independent of any venom effect on papillary sphincter tone. The morphological characteristics of the experimental disease appear similar to those observed at autopsy in acute hemorrhagic pancreatitis in humans.


Digestive Diseases and Sciences | 1984

Pancreatitis associated with alcoholic liver disease

Ian G. Renner; William T. SavageIII; Nigel H. Stace; Jose L. Pantoja; Wayne M. Schultheis; Robert L. Peters

The prevalence with which alcoholic pancreatitis is associated with alcoholic liver disease is unclear. To investigate this association further, we have reviewed the autopsy findings of 1022 patients who died from alcoholic liver disease and compared these findings with those from 352 patients who died from cardiac or pulmonary disease. All patients who died from liver disease had a history of chronic alcoholism with clinical and biochemical evidence of severe liver damage. Death resulted from hepatic coma, gastrointestinal bleeding, or infection. Liver disease patients were classified into two groups: (1) those with cirrhosis (77%) and (2) those without cirrhosis but with acute and/or chronic sclerosing hyaline necrosis (23%). Anatomic and histopathologic changes characteristic of chronic pancreatitis were found in 203 patients in approximately the same frequency (20% and 18%, respectively) in both groups. Acute pancreatitis without chronic lesions was observed in 8% and 10% of both groups, respectively. In the control group of 352 autopsies (122 cardiac and 230 pulmonary patients), the overall prevalence of pancreatitis, at 2.6%, was significantly (P<0.001) lower than that observed in the alcoholic liver disease groups. A total of 22 cases (50%) dying from acute or chronic sclerosing hyaline necrosis had severe chronic calcifying pancreatitis compared to 29 patients (18%) (P<0.001) dying from cirrhosis. By contrast, dense fibrosis was significantly (P<0.001) more commonly observed in patients with cirrhosis. We conclude that pancreatitis occurs frequently in patients dying from alcoholic liver disease but is an uncommon finding in patients dying from other causes. Biliary tract pathology was more prevalent (P<0.05) in patients dying from cirrhosis without pancreatitis than those patients dying from liver disease with pancreatitis. In the control group of patients dying from pulmonary or cardiac disease, biliary pathology was far less frequently (P<0.01) observed.


International Journal of Gastrointestinal Cancer | 1986

Ceruletide-induced acute pancreatitis in the dog and its amelioration by exogenous secretin

Ian G. Renner; James R. Wisner

SummaryLarge pharmacological doses of ceruletide administered to conscious dogs by intravenous (i.v.) infusion uniformly induce a severe acute necrotizing pancreatitis within 4 h. High-dose i.v. secretin administered for a period of 24 h after cessation of ceruleetide infusion resulted in a significant amelioration of the acute pancreatitis compared to non-secretin-treated dogs with acute pancreatitis. Light microscopy of the pancreas in secretin-treated dogs revealed a significant decrease in edema, polymorphonuclear leukocyte infiltration, cell necrosis and acinar cell vacuolization. Serum amylase levels in secretin-treated dogs were significantly decreased compared to non-secretin-treated dogs. The results of this study suggest that high-dose i.v. secretin exerts a beneficial effect on pre-established, ceruletide-induced acute pancreatitis in dogs.

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James R. Wisner

University of Southern California

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H. Rinderknecht

University of Southern California

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Adrian P. Douglas

University of Southern California

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Stephan B. Abramson

University of Southern California

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Susumu Ozawa

University of Southern California

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Jose L. Pantoja

University of Southern California

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Nigel H. Stace

University of Southern California

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Allan G. Redeker

University of Southern California

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John C. Hoefs

University of California

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John M. Weiner

University of Southern California

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