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D R Strombeck

Publications and source records attributed to D R Strombeck.

51 records · Page 3Linked to original sources

Effects of functional nephrectomy on the disappearance rates of canine serum amylase and lipase.

The rates of disappearance of intravenously injected amylase and lipase were determined in dogs before and after ligation of the renal vessels. Functional nephrectomy increased the half life of serum amylase from 5 to 14 hours and of serum lipase from 2 to 11 hours. Serum amylase values increased relatively little in dogs with a functional nephrectomy when enzymes were not infused. The increase in serum amylase activity was not correlated to the increase in serum urea nitrogen. The canine kidney was responsible for the disappearance of part of the amylase and lipase from the serum. Only trace amounts of either amylase or lipase activity were found in the urine. It is assumed the canine kidney inactivated these enzymes.

Amylases↗

Coagulopathy and encephalopathy in a dog with acute hepatic necrosis.

Disseminated intravascular coagulation developed secondary to hepatic necrosis in a 5-year-old Saint Bernard. Although the coagulopathy responded to treatment with heparin, the dog died from the combined effects of gastric hemorrhage and encephalopathy, both of which are complications of hepatic necrosis.

Amino Acids↗

Comparison of the rate of absorption and proteolysis of [14C]choleragen and [14C]bovine serum albumin in the rat jejunum.

[14C]choleragen was used to study the rate of disappearance of choleragen enterotoxin from the jejunum of rats. [14C]bovine serum albumin (BSA) was studied in a similar manner. Almost one-third of the labeled toxin had disappeared from the intestine after 6 h. Its rate of disappearance was the same in germfree rats as in conventional rats. The rate of proteolysis of [14C]choleragen and [14C]BSA by intestinal mucodal lysosomal enzymes was also studied. Neither was significantly degraded by neutral proteases; however, heat-inactivated toxin was. They were all degraded by acid proteases; however, the rate of BSA proteolysis was only one-third of that of toxin. Soybean trypsin inhibitor had no effect on the in vivo disappearance of toxin nor on the acid proteases. It did inhibit the neutral protease digestion of heat-treated toxin. Aprotinin and protamine inhibited disappearance in loops of gut but had no effect to inhibit degradation rates. Gangliosides inhibited both rates of disappearance and proolysis of toxin. These agents had some different effects on disappearance rates and proteolysis of BSA. The data indicate that cholera enterotoxin is absorbed by intestinal mucosal cells and is degraded by acid proteases in the cells.

Absorption↗

Binding of cholera toxin to mucins and inhibition by gastric mucin.

The effects of mucin on cholera toxin induced intestinal secretion was studied in the rat small intestine. Gastric mucin inhibited secretion when premixed with cholera toxin on an equal dry-weight basis. Neither salivary nor intestinal mucin inhibited the toxin's action in the intestine. Inhibition by gastric mucin was not reversed by a mucolytic agent or by hexoses or agents that bind hexoses. Plasma and serum did not inhibit the effects of cholera toxin in the intestine. Choleragen was labeled with (14)C and its binding to mucins and ganglioside was studied. Gastric mucin was shown to bind to choleragen, but less binding was observed when choleragen was dissociated into subunits by acid pH. Salivary and intestinal mucins bound intact choleragen but not the subunits at acid pH. Salivary mucin binding was reversed by N-acetyl neuraminic acid and neuraminidase. Ganglioside bound choleragen in both the intact and dissociated forms. Binding to the dissociated form was reversed by wheat germ agglutinin. Gastric mucin and ganglioside competed for binding to choleragen with the binding of intact choleragen greater for ganglioside and the affinity of the subunits greater for gastric mucin. Electrophoresis of labeled choleragen showed uniform labeling of the subunits dissociated by acid pH, but a major part of cholera toxin was found not to be labeled when fractionated with sodium dodecyl sulfate and 2-mercaptoethanol.

Animals↗

Development of gastroscopic food sensitivity testing in dogs.

The aims of this study were to develop a gastroscopic food sensitivity testing (GFST) technique for clinical use in dogs and to determine if the results of GFST were influenced by the feeding of a hypoallergenic diet immediately before the testing period ("unmasking"). The technical requirements for GFST were devised during a total of eight endoscopies performed in four healthy dogs. GFST was performed in anesthetized dogs in sternal recumbency. Food extracts were dripped onto the dependent aspect of the body of the stomach via plastic tubing passed through the endoscope. Changes were observed within 2 to 3 minutes of application, and included localized mucosal swelling and erythema, generalized mucosal erythema, and hyperperistalsis. The influence of "unmasking" was then examined in 6 atopic and 2 healthy dogs, which underwent GFST on three occasions, 4 weeks apart. Before the first and third testing periods, the dogs consumed a commercial dry dog food. For 5 days before the second testing period the dogs were fed a hypoallergenic elemental diet. Oral challenges were performed to identify which of the dogs had clinically overt immediate food sensitivity. Localized swelling was most frequently correlated with positive challenge PO. No positive reactions occurred in response to the negative control extract (lamb). The number of positive GFST results increased after feeding the hypoallergenic diet. In conclusion, these preliminary results indicate that GFST holds substantial promise for the diagnosis of immediate food sensitivities affecting the gastrointestinal tract. The sensitivity of the procedure appears to be enhanced by preceding testing with a hypoallergenic diet.

Allergens↗