Alloxan diabetic neuropathy: electron microscopic studies.

Peripheral nerves of diabetic rats were studied 2 years after alloxan injection. We observed demyelination and remyelination, axonal degeneration and regeneration, reduplication of basal laminae around vessels and Schwann's cells, as well as onion bulb formation by proliferated Schwann's cells. Crystalline deposits composed of aggregates of fibrillary electron dense material often occurred in vessel walls and endoneurium of diabetic animals but rarely were seen in nerves from age-matched control animals. Glycogen accumulated in myelinated and unmyelinated axons within mitochondria. Axoplasmic inclusions resembling Lafora's bodies and the inclusions of glycogenosis type IV were frequent and often were accompanied by deposits of particulate glycogen. The findings suggest that the neuropathy in alloxan diabetes is caused by metabolic impairment of anxons, Schwann's cells, and vessels, leading to segmental demyelination and axonal degeneration.

Further evidence for an intestinal phase hormone that stimulates gastric acid secretion.

The studies described in this report were directed at isolating the hormone responsible for the intestinal phase of gastric acid secretion. One hundred and ten extracts of hog intestinal mucosa, each representing the yield from about 3,000 hogs, were prepared by a method for isolating small peptides that involved heating, absorption on diethylaminoethylcellulose (DEAE), and acid precipitation. All extracts stimulated gastric acid secretion in acute gastric fistula rats, and 56 were highly active according to stringent criteria that required a greater than 50 percent increase in acid output above basal in at least 60 percent of rats. Increasing doses of extract stimulated increasing acid production according to a regular dose-response relationship. Twelve highly active extracts were tolerated without side effects when infused into dogs with Heidenhain pouches and produced a mean 22 fold increase in acid output above basal. The gastrin content of 73 extracts, measured by radioimmunoassay in two independent laboratories, averaged 5,80 ng. per rat dose of extract, which is approximately 1/500 of the minimal stimulating dose of hog gastrin. No extract contained sufficient gastrin to produce an acid secretory response. Administration of the extract together with a maximal stimulating dose of pentagastrin in rats significantly augmented the maximal acid secretory response. Finally, comparison of the acid secretory response to portal and systemic intravenous infusion of the extract in acute gastric fistula rats demonstrated significant inactivation by passage through the liver, in contrast to the results of similar studies of hog gastrin. It is concluded that the extract had all of the known physiologic properties of the intestinal phase hormone and very likely contained the intestinal phase hormone.

Liver regeneration after portacaval transportation in rats.

General recognition of the presence of a specific hepatotrophic factor in portal blood that is necessary for liver regeneration was delayed by two major problems. First, there was a long period of confusion regarding liver atrophy, liver hypertrophy, and cellular hyperplasia. Second, because only exposure to other liver tissue destroys the hepatotrophic activity, all of the studies that were based on bypassing the portal blood into the systemic circulation merely diluted the active substance, which still was available to the hepatocytes by recirculation through the hepatic artery. These problems have been resolved by the development of more sophisticated methods by which to assay liver regeneration and by the introduction of the double liver model to study regeneration. During the time when liver weight alone was used to assess regeneration, the regenerative capacity of the liver was reported to be much greater after portacaval transposition than after end-to-side portacaval shunt, a finding that is inconsistent with current knowledge of the hepatotrophic portal blood factor. To re-evaluate the effect on liver regeneration of providing a compensatory systemic venous inflow after complete portal diversion, 40 partially hepatectomized inbred rats which had previously undergone either a sham operation and end-to-side portacaval shunt or a portacaval transposition were compared on the basis of six separate criteria of regeneration. All of the livers actively regenerated and no significant advantage of providing a substitute systemic venous inflow to the liver could be detected by any of the criteria.

Intrahepatic bile duct rupture following blunt abdominal trauma.

The natural history of intrahepatic bile duct rupture secondary to blunt trauma is not known. A unique case of bilateral hepatic lobar duct rupture is presented to demonstrate the clinical features and potential complications of this injury. Operative intervention is not always indicated and treatment should be dictated by the specific lesion.

Simplified technic for orthotopic liver transplantation in the rat.

A new surgical procedure has been developed to simplify the difficult, complex technic of orthotopic liver transplantation in the rat that we previously described. This procedure eliminates the hepatic artery anastomosis and specifically changes the sequence of anastomoses of the vena cava and portal vein to minimize splanchnic congestion and hepatic ischemia. This has simplified and shortened the operation and has eliminated the need for an extracorporeal portosystemic shunt. Seventy-two per cent operative survival was achieved in fifty-seven orthotopic liver transplantations. This simplified technic of orthotopic liver transplantation in the rat can be applied widely to studies of liver physiology, immunologic rejection, and liver preservation.

Long-term exocrine function of the pancreas transplant.

The long-term exocrine function of fifty-nine pancreaticoduodenal isografts was evaluated in rats for up to one year post transplantation. At one, three, six, nine, and twelve months after transplantation the grafts were cannulated and the exocrine secretion was collected. The volume, protein content, pH, amylase and trypsin concentrations, and electrolyte composition of the secretion were compared with those obtained from the host pancreas in nineteen control rats. Twenty-four hour secretion studies demonstrated normal basal function of the pancreas transplant when compared with that of the host. Pancreozymin stimulation caused an increase in volume, trypsin concentration, and amylase concentration of the graft pancreas secretion that was similar to those seen in the host. These studies indicate that there is normal exocrine secretion of pancreas transplants in the absence of rejection and that denervation of the gland has little direct effect on over-all pancreatic function.

Changing concepts in the management of splenic trauma.

Overwhelming sepsis may occur, even years later, in asplenic children or adults who are otherwise healthy. The injured spleen can be successfully repaired in almost all patients. Repair should not be attempted if the survival of the patient would be jeopardized by continuing or delayed hemorrhage. If splenectomy is unavoidable, the patient must be informed of his vulnerable state and be protected as much as possible by vaccines and by early aggressive treatment of all infections.

Experience with a simplified trauma registry: profile of trauma at a university hospital.

A simplified computer-based trauma registry system with well-defined limits of data capture is presented. This registry was utilized to describe the profile of trauma at a university hospital. In 1 year there were 882 trauma victims hospitalized, with an overall mortality of 3.3%. The majority of the patients had relatively minor injuries, primarily involving soft tissue and bone. Severe multiple trauma was associated with a significant mortality. Intracranial or intra-abdominal injuries occurred in less than 10% of the patients. Transport accidents, falls, and assaults were the cause of injury in 70%. Key access to specific information about the trauma patient population demonstrated the potential of the registry system. The advantages and limitations of the registry are discussed.

The roll-bar hand.

This report describes a new hand injury seen in passengers in dune buggies having rollover accidents. Since these vehicles are usually driven off the road and far from treatment centers the treatment of these injuries is often delayed. As the rollover takes place, the reflex action--usually of the passenger--is to grasp the roll bar. A crush-avulsion injury occurs at the level of the metacarpals, with the thumb frequently spared. Wound contamination, delay in treatment, and the frequency of other serious injuries add to the seriousness of this injury. Redesign of the roll bar, provision of better passenger protection, and an internal grasp support are suggested to reduce its incidence.