George A. Hallenbeck

Effect of excluding pancreatic juice from duodenum on secretory response of pancreas to a meal.

Conclusion 1. When canine pancreatic juice secreted in response to a meal was permanently removed by the method used in these experiments, the total volume of juice secreted was significantly greater than was the case when the juice was replaced in the duodenum. 2. A similar reduction in the volume of postprandial pancreatic secretion occurred when tenth normal sodium bicarbonate solution was instilled into the duodenum in place of pancreatic juice. 3. No similar reduction in secretion occurred when equivalent volumes of isotonic saline solution were substituted for pancreatic juice.

A comparison of autoplastic, allogeneic and xenogeneic perfusion of isolated kidneys***

Summary Kidneys of pigs, monkeys and rabbits were perfused by dogs, and kidneys of dogs were similarly perfused by domestic pigs and by a strain of miniature pigs. Autoplastic and allogeneic perfusions of dog and pig kidneys served as control experiments. Although modest differences were noted in the rapidity of the reaction when different combinations of animals were used, the xenogeneic perfusion systems tested were characterized by rapidly developing diminution and, finally, cessation of renal blood flow, by retention of platelets and leukocytes in the kidneys, and by renal edema, vascular congestion and hemorrhage with foci of damage to endothelium. This reaction, as it occurred in pig kidneys perfused by dogs, was not modified significantly by any of a group of drugs that included serotonin antagonists, antihistaminic agents, protease inhibitors, corticosteroids, an immunosuppressive agent, and certain combinations of these. In three experiments there was evidence that, when miniature pigs were fed dog serum immediately after birth by cesarean section and were used (when they were 5 months of age) to perfuse dog kidneys, the perfused kidneys maintained normal blood flow for longer periods of time than did those perfused by untreated miniature pigs; nevertheless, acute “rejection” occurred in all tests within six hours.

THYMECTOMY IN NEWBORN PIGS.

Summary The effects of neonatal thymectomy were studied in the pig. No differences were found in the pattern of rejection of allografts of skin or in the production of antibody in response to Salmonella pullorum antigen between control animals and animals that underwent total thymectomy within 48 hours of birth. Allografts were applied within the first week of life, and thymectomized and nonthymectomized animals rejected them in about eight days. Production of serum antibodies, tested when the pigs became 2 months of age, was found to be equal in all animals. No “wasting” was observed up to one year after the operation, and both control and thymectomized animals had higher concentrations of lymphocytes in the blood when 2 months of age than at birth. Various theories to account for these findings are discussed, and some comments are made about the observation that newborn pigs can reject allografts within a few days after birth even though other authors have shown that they are, in some other respects, relatively incompetent immunologically.

An instrument for colorectal anastomosis without sutures

Summary and ConclusionsA new instrument for joining the colon to the lower part of the rectum without sutures has been described. Initial tests in dogs and its use in one patient have been satisfactory. Further trial of the device is considered justified.

RELATIONSHIP BETWEEN ATROPHY OF THE PANCREAS AND GASTRIC SECRETION: AN EXPERIMENTAL STUDY.

Summary and conclusions1. The finding that complete obstruction of pancreatic ducts is followed by increased daily secretion of hydrochloric acid from Heidenhain pouches in dogs was confirmed.2. Extracts of canine atrophic pancreatic tissue, prepared by a method successfully used to obtain gastrin from antral mucosa and a gastric secretagogue from Zollinger-Ellison tumors, did not stimulate gastric secretion in dogs with gastric pouches.3. Evidence was presented to support the concept that gastric hyper-secretion following complete obstruction of pancreatic ducts in dogs is not stimulated by a humoral secretagogue liberated from the atrophic pancreas, but is caused in some way by exclusion of pancreatic juice from the duodenum.

The pancreas and gastric secretion: failure of pancreatectomy to prevent inhibition of gastric secretion by secretin

A second commercially prepared secretin has been found to inhibit the acid secreted by Heidenhain pouches in dogs in response to a meal but not to histamine. This inhibition is not affected by pancreatectomy.

Renal homotransplantation in dogs

Summary The findings in 87 dogs in which renal autotransplantation, renal homotransplantation without the use of immunosuppressive agents, or renal homotransplantation with the administration of an immunosuppressive drug, azathioprine (Imuran), suggest that, in the rejection of the homotransplanted canine kidney: (1) the initial morphologic changes occur in vessel walls and (2) the destruction of the graft is an ischemic process. The significance of the inflammatory cellular infiltrate was discussed, and the mechanism of rejection of the homotransplanted kidney was compared to inflammatory responses produced by other stimuli. The persistence of foci of inflammatory cells was noted in the homotransplanted kidneys in animals treated with azathioprine to inhibit rejection, even in the presence of good renal function. Vascular changes were not significant in this group of treated animals.

Restoration of Immunologic Competence of Neonatally Thymectomized Mice by Isogeneic and Xenogeneic Thymic Grafts

Conclusions The effectiveness of intraperitoneal grafts of thymus and other tissues was tested by observing their ability to restore to neonatally thymectomized C57BL/6 mice their ability to reject the Walker 256 carcino-sarcoma of rats. Grafts of isogeneic thymic tissue, both free and in cell-impermeable Millipore chambers, were effective. Grafts of isogeneic splenic tissue from 14-day-old mice were effective if transplanted free but not if enclosed in Millipore chambers. Free grafts of splenic tissue from neonatally thymectomized mice were ineffective. Free grafts of isogeneic duodenum, lung, liver, kidney, skeletal muscle, and submaxillary and thyroid glands were ineffective. Free grafts of xenogeneic thymus tissue from Sprague-Dawley rats, either neonatal or 14 days of age, were effective. The effectiveness of thymic grafts in this model increased as the mass of tissue transplanted was increased and was independent of the finding of histologically normal thymic tissue at the end of the period of observation.

Sphincter saving operations for carcinoma of the distal twenty centimeters of the rectum and colon.

Summary Adequate information supports the thesis that most operable cancers between 5 and 20 cm. from the dentate line can be controlled as well by sphincter preserving operations as by resection of the rectum and sphincter. The operations have been developed to a point that in skilled hands their mortality rates are similar to the rate for the Miles operation. It is to the patients advantage and pleasure to avoid colostomy if possible and justifiable. Probably no more than a third of the patients having operable lesions in the last 20 cm. of rectum need have permanent colostomy today.

Effect of portal ligation and of Eck's fistula on hepatic blood flow and concentration of blood ammonia

Abstract The incidences of portal encephalopathy in dogs with ligated portal veins, portacaval transpositions, or Ecks fistulas made de novo and after ligation of portal veins have been determined, and factors responsible for this complication have been sought by measuring total hepatic blood flow and by studying ammonia metabolism in these animals. Signs of portal encephalopathy developed spontaneously in 6 of 13 dogs with only Ecks fistulas and in 3 additional ones after a meat tolerance test. Portal systemic encephalopathy was not evident in any of the other animals studied except for one dog with an Ecks fistula made after ligation of portal vein; this dog became ill after a meat tolerance test. The results indicate that the signs of portal encephalopathy observed in dogs with Ecks fistulas made in the absence of a previously established portal systemic collateral circulation do not result solely from the combination of decreased hepatic blood flow and increased concentration of ammonia in the blood.