Search PubMed⌕ Search

Biomedical subjects

H A Reber

Publications and source records attributed to H A Reber.

At least 127 records · Page 7Linked to original sources
PubMed1983

The creation of a surgical endoscopy training program--is there sufficient clinical material?

The American Board of Surgery now requires surgical training programs to provide instruction in gastrointestinal endoscopy. In order to demonstrate that an independent Surgical Endoscopy Service could generate sufficient patient volume for an endoscopy training program, we reviewed our experience before and after the organization of such a service. In the year before formation of the Surgical Endoscopy Service (1981), surgical endoscopists performed 134 upper gastrointestinal (UGI) endoscopies and 25 colonoscopies for a total of 159 procedures. This represented 17% of the total institutional endoscopies performed. Further analysis indicated that 30.5% of UGI endoscopies and 24% of colonoscopies were performed on patients referred from surgical services. During the first year of the Surgical Endoscopy Service (1982), we performed 322 UGI endoscopies and 102 colonoscopies for a total of 424 procedures. This represented an increase to 36.5% of the total institutional endoscopies. During this time 41% of the UGI endoscopies and 33% of the colonoscopies were performed on patients referred from surgical services. Thus, with the formation of a Surgical Endoscopy Service we were able to dramatically increase our procedure volume and to provide effective gastrointestinal endoscopic training for our residency program. This confirmed our premise that in a typical university training program there is sufficient clinical material to provide training in surgical endoscopy.

Academic Medical Centers↗
PubMed1982

Protein secretions in hamsters with pancreatic carcinoma.

Pancreatic secretions from the hamster model for pancreatic ductal adenocarcinoma were analyzed to determine whether alterations had occurred in the protein composition. CCK-and secretin-stimulated secretions were collected from 13 animals with cancer and 16 normal controls. Subsequent separation of the proteins by isoelectric focusing showed the following: (1) Significant changes occurred in the protein composition from animals with carcinoma. An unusually dark band was present at pH 7.5 just below amylase (pH 7.65); two unidentified bands, present in the normals at pH 6.9 and 7.0, were missing; and marked decreases occurred in the cathodic proteins with isoelectric points above pH 9, (2) CCK provided the optimal stimulus for differentiating specimens from animals with carcinoma from the normal controls. (3) The protein concentrations of CCK-stimulated secretions of animals with carcinoma were significantly lower than the controls. We have concluded that the protein alterations which have occurred in the hamster model for pancreatic ductal adenocarcinoma warrant further investigation.

Animals↗
PubMed1981

Pancreatic secretions as a clue to the presence of pancreatic cancer.

Pancreatic secretory function is abnormal in at least 90% of patients with pancreatic cancer. These abnormalities may be due to direct involvement of the secretory cells by the malignant process and/or the effects of pancreatic duct obstruction. There is no specific stimulus (secretin and/or cholecystokinin, CCK, or CCK-like hormones) of pancreatic secretion that is clearly superior to any other as a test of pancreatic function. Pancreatic secretion is abnormal in animal models of pancreatic cancer and secretory abnormalities antedate the histologic appearance of the cancer. A decrease in protein secretion after CCK stimulation is the most significant finding in experimental partial pancreatic duct obstruction (the condition most commonly seen in pancreatic cancer). In the absence of any identifiable high-risk group within the population, it is unlikely that the testing of pancreatic function provides a means for the earlier diagnosis of pancreatic cancer.

Animals↗
PubMed1981

Pancreatic function in domestic cats with pancreatic fluke infection.

Thirty-one of 290 cats (10.7%) from the area around St Louis, Mo, were infected with Eurytrema procyonis. In some cats, the pancreas was severely affected, with almost complete atrophy and fibrous replacement of the gland. Both bicarbonate and protein secretions were impaired, although clinically evident pancreatic insufficiency was not seen.

Animals↗
PubMed1981

Effect of 16, 16 dimethyl prostaglandin E2 on aspirin-induced permeability changes in the pancreatic duct.

Perfusion of the pancreatic duct with acidified aspirin in cats increased the permeability of the duct to HCO3-. Intravenous administration of the synthetic prostaglandin analog 16,16 dimethyl prostaglandin E2 (PGE2) prevented this permeability change. The effect was dose-related and at the highest dose (50 microgram/kg/hour) was essentially complete. The beneficial effect of the PGE2 was apparent even when it was given after the duct had been exposed to aspirin. PGE2 had no effect on pancreatic water or electrolyte secretion in the unstimulated nonsecreting gland. No histologic changes in the pancreatic ducts were seen after exposure to aspirin, PGE2 or both. The effectiveness of PGE2 in restoring membrane permeability towards normal suggests the possibility of its therapeutic role in pancreatitis.

16,16-Dimethylprostaglandin E2↗
PubMed1981

Pancreatic cancer: diagnostic value of pancreatic function tests.

Pancreatic secretion is abnormal in at least 90% of patients with pancreatic cancer. Any of the standard tests of pancreatic function that employ an exogenous secretin or CCK-like stimulus effectively reveal those abnormalities. However, despite a high sensitivity, the tests lack the specificity necessary to distinguish reliably between pancreatic cancer and chronic pancreatitis. With the current practice of testing pancreatic function in symptomatic patients and in the absence of an identifiable high-risk group within the population, it is unlikely that the established pancreatic function tests will provide a means for the earlier detection of pancreatic cancer.

Animals↗
PubMed1980

The effect of bile salts on the pancreatic duct mucosal barrier.

The effects of various bile salts on the permeability of the pancreatic duct in cats have been investigated. The sodium salts of cholic, glycocholic, taurocholic, chenodeoxycholic, glycochenodeoxycholic, deoxycholic and glycodeoxycholic acids were perfused through the main duct in concentrations similar to those found in the duodenal contents (15-42 mM). HCO3- and Cl- fluxes were determined before and after perfusion. The unconjugated dihydroxy bile salts increased permeability to these anions to a greater degree than the trihydroxy bile salt, but all were damaging to the duct when they were perfused at an alkaline pH (8.4-9.1). The glycine conjugates of the bile salts were as damaging as the unconjugated form, but 42 mM taurocholate was more damaging than 42 mM glycocholate. When 25 mM glycocholate was perfused at pH 2.4 there was potentiation of the damage produced during perfusion of glycocholate at pH 8.7. Sterile cat bile did not damage the duct, but infected bile did. The ability of bile salts to increase the permeability of the pancreatic ducts must be considered as a possible aetiological factor in the pathogenesis of inflammatory and malignant diseases of the pancreas.

Animals↗
PubMed1979

The pancreatic duct mucosal barrier.

The main pancreatic duct in cats possesses a relatively strong barrier to the diffusion of bicarbonate ions (HCO3-). We studied some of the characteristics of this barrier by perfusing the duct with a solution similar in composition to pancreatic juice before and after exposing the duct mucosa to various test agents. The difference in net flux of HCO3- across the duct before and after exposure to the test agent reflected damage to the barrier. The barrier was damaged by infected bile, aspirin (pH 2.3), hydrochloric acid (pH 2.3), ethanol (5 to 10 per cent), and secondary bile acids. It was not damged by sterile bile, aspirin (pH 6.5), and primary bile acids. These data indicate that the barrier to back diffusion in the pancreatic duct has unique properties, different in some respects from the properties of the gastric mucosal barrier. Furthermore, the barrier is vulnerable to some agents thought possibly to have a role in the pathogenesis of pancreatitis and pancreatic cancer.

Animals↗
PubMed1978

Management of external gastrointestinal fistulas.

We analyzed the course of 186 patients with external gastrointestinal fistulas treated at the University of California Medical Center, San Francisco from 1968 to 1977. There were 82 patients in the earlier group (1968-1971) and 104 patients in the later group (1972-1977). The groups differed in that 35% of patients in the earlier group received TPN, but 71% of patients in the later group received TPN. Of the patients who did not receive TPN, 93% had been adequately nourished using tube feeding methods. The two groups were otherwise similar. The fistula-related mortality (11%) and the spontaneous closure rate of the fistulas (32%) was unchanged over the ten year period. Thus, the principal impact of TPN was to simplify the nutritional management rather than to alter the outcome. When malignancy, previous abdominal irradiation, Crohn's disease, or a short (<2 cm) fistula tract were present, spontaneous closure was less likely than when none of these factors were present (20% versus 47%). Sixty-eight per cent of the deaths occurred in patients with uncontrolled sepsis. Fifty per cent of the deaths were due to the primary disease and were unrelated to the fistula. Spontaneous closure could not be expected to start until sepsis was controlled. Because over 90% of patients whose fistulas closed spontaneously did so within one month after infection was eradicated, we recommend operative closure for most fistulas that persist beyond that time. The most reliable operation is excision of the bowel from which the fistula arises with end-to-end anastomosis. Fistulas not amenable to excision should be managed by bypass.

Adolescent↗
PubMed1977

Micropuncture study of pancreatic secretion in the cat.

Using micropuncture techniques, pancreatic electrolyte secretion was studied in 50 female mongrel cats. During maximal secretin stimulation (GIH, 4 to 6 U per kg-hr), juice was collected from intralobular (10 to 50 mu diameter), and extralobular (25 to 300 mu diameter) ducts by micropuncture and compared with juice simultaneously collected from the main duct. The juice [Cl-] steadily decreased from intralobular ducts (112 +/- 9 mEq per liter) to the main duct (46 +/- 8 mEq per liter). During in vivo perfusion, secretion of H2O and HCO3- by the extralobular ducts (25 to 150 mu diameter) was sensitive to secretin. There was no evidence for secretion by the main duct. Pancreatic secretion of water and electrolytes appears to result from the admixture of a Cl-rich primary secretion originating from intralobular structures and a larger volume of HCO3- -rich fluid originating from the smaller extralobular ducts. HCO3- cl- exchange in these ducts accounts for the characteristic changes in concentrations of HCO3- and Cl- as the flow rate varies.

Animals↗