Diminished brush border membrane Na-dependent L-alanine transport in acute viral enteritis in piglets

We studied sodium-dependent uptake of L-alanine into small intestinal brush border membrane vesicles (BBMV) isolated from piglets 40 h after infection with transmissible gastroenteritis (TGE) virus. Vesicles from TGE-infected pigs and uninfected litter-mate controls showed comparable degrees of enrichment and purity. In BBMV prepared by conventional techniques, [3H]L-alanine "overshoot" (peak uptake/equilibrium uptake) in the presence of a Na gradient was preserved in TGE BBMV, unlike [3H]D-glucose "overshoot," which was reduced. When these experiments were repeated using vesicles of greater purity, initial rates of Na-dependent L-alanine influx were reduced in BBMV from infected piglets under voltage clamped conditions with valinomycin. These studies demonstrate a specific amino acid transport defect in the small intestinal epithelium during acute viral diarrhea. They demonstrate too that brush border L-alanine-Na co-transport, although reduced, is present after viral damage, confirming previous studies that showed additive effects of amino acid and glucose on jejunal epithelial Na+ transport in transmissible gastroenteritis. Our findings support the concept that, in viral enteritis, oral rehydration solutions containing amino acid and glucose have a theoretical advantage over glucose electrolyte solutions because they facilitate brush border Na+ entry by two carrier mechanisms.

Peptic ulcer disease in children: etiology, clinical findings, and clinical course

The records of all children with peptic ulcer disease at the Hospital for Sick Children were retrospectively evaluated, excluding neonates, throughout a 5-year period. Only cases with a definite ulcer crater identified either at endoscopy or at surgery were included. There were 36 patients, 20 boys and 16 girls. Duodenal ulcers were more common than gastric ulcers (2.8:1). Ages ranged from 3 months to 17 years, with a mean age of 10 years. Patients were reviewed with respect to etiology of peptic ulcer disease, age when first examined, initial symptoms, and clinical course. Patients were divided into two groups, those with primary (n = 19) and those with secondary (n = 17) peptic ulcer disease. All peptic ulcers in patients younger than 10 years of age were secondary in nature. Secondary ulcers occurred generally in association with a severe underlying illness (11/17), and many ulcers necessitated emergency surgery because of perforation and/or severe hemorrhage (8/17). None of these patients had chronic or recurrent symptoms. In contrast, in children with primary peptic ulcer disease, initial symptoms were more benign. Most patients had abdominal pain and only one required emergency surgery. Children with primary duodenal ulcer disease had a high incidence of recurrent symptoms (67%), however, with surgery for intractable disease necessitated in 40%. Single-contrast barium meals were found to be unreliable in establishing a diagnosis of peptic ulcer disease, particularly cases of gastric ulcer disease.

Effect of glucocorticoid on piglet jejunal mucosa during acute viral enteritis

We measured the effect of pharmacological doses of glucocorticoid on piglet jejunal structure and function during acute viral diarrhea. Weaned piglets, infected experimentally with transmissible gastroenteritis virus, a coronavirus that induces a diarrheal illness similar to human rotavirus infection, received methylprednisolone (30 mg/kg) or saline intramuscularly at 48 and 72 h after infection; noninfected littermate controls were similarly injected with methylprednisolone. Animals were killed at 96 h, at the height of diarrhea, and jejunal epithelium was studied in vitro. Transmissible gastroenteritis, as expected, induced structural, enzyme, and Na transport abnormalities. Methylprednisolone did not affect small intestinal structure or function of noninfected control piglets. In transmissible gastroenteritis-infected piglets, jejunal villi were longer and glucose-facilitated Na absorption was greater after methylprednisolone than after saline treatment. Increased glucose stimulation of Na flux in vitro in the methylprednisolone-treated infected group was not attributable to enhanced Na+-K+-ATPase activity and occurred despite persistence of the virus within mucosal cells, shown by immunofluorescence microscopy. In this piglet model of viral diarrhea, early regeneration of absorptive surface that precedes recovery of disaccharidase function is accelerated by glucocorticoid therapy.

Alanine enhances jejunal sodium absorption in the presence of glucose: studies in piglet viral diarrhea

We measured the response of jejunal sodium (Na) absorption to neutral amino acid (L-alanine) and to dipeptides (L-alanyl-L-alanine, glycylsarcosine) in normal piglets and in piglets with acute viral diarrhea after experimental infection with transmissible gastroenteritis (TGE) virus. In the TGE jejunum villi were blunted, crypts were deepened, and the epithelium was composed of relatively undifferentiated cells with reduced disaccharidase, decreased sodium-potassium-stimulated ATPase, and elevated thymidine kinase activities. The response of Na absorption to a maximal concentration of L-alanine (20 mM) or D-glucose (30 mM) was significantly blunted in TGE jejunum in Ussing chambers. However, the addition of L-alanine together with D-glucose caused a significantly greater increment of Na absorption than either L-alanine or D-glucose alone in control and TGE tissue. The effect of Na absorption of the dipeptide L-alanyl-L-alanine (10 mM), which was rapidly hydrolyzed by control and TGE mucosa, was similar to that of L-alanine (20 mM), while glycylsarcosine, a poorly hydrolyzed dipeptide, did not change net Na absorption in the jejunum. Our data support the concept of separate carrier systems for neutral amino acid and hexose in the crypt-type intestinal epithelium characterizing viral enteritis. We speculate that a sodium-cotransporting amino acid, if added to oral glucose-electrolyte solutions, could benefit oral rehydration therapy in acute viral diarrhea; neither of the dipeptides tested here can be expected to enhance absorption to any greater extent than its constituent amino acids.

When the doctor needs a doctor: special considerations for the physician-patient

The treatment of an ill or impaired physician may present difficulties not typically encountered in other patients. Potential complications arise from the temptation for physicians to diagnose and treat themselves, their tendency to obtain "informal" consultations regarding personal symptoms, their difficult transition from the role of doctor to that of patient, and the inadvertent assumption of a "VIP" status in the hospital. These difficulties may be increased by the denial of illness by the physicians themselves and their families and colleagues. This denial is partially determined by legal, financial, social, professional, and psychological factors. Specific recommendations on caring for an ill physician are presented.

The incidence of exhibitionism in Guatemala and the United States

Previous speculation based on a mail survey of psychiatrists suggested that exhibitionism is rare in Latin American countries. This survey of potential victims conducted in Guatemala and using a comparable United States facility as a control, shows the incidence in the two countries to be essentially the same. This suggests that the psychopathology of the exhibitionist has more to do with the act than does the culture in which it occurs.

Brief reactive psychosis: a psychodynamic interpretation

The diagnosis "brief reactive psychosis" leaves little implied in the way of etiology or treatment approach. Three case histories are presented to illustrate the term, followed by brief summaries of the major dynamics involved. The older diagnostic term "hysterical psychosis" is discussed, and a parallel is drawn between this form of brief reactive psychosis and others so that they may be psychodynamically understood and that treatment may be rationally based upon this model.

Host-range properties of murine xenotropic and ecotropic type-C viruses

Host-range properties of xenotropic (x-tropic) and ecotropic mouse type-C viruses were determined. NB-tropic viruses replicated only in mouse and rat cells, whereas x-tropic viruses, which do not exogenously infect mouse cells, grew in cells from various other mammalian species. Great variability in susceptibilities to x-tropic viruses was demonstrated in cells from heterologous species and in cells from a single species (human). Although rat cells were susceptible to both types of viruses, hamster cells were uniformly resistant. In addition, the x-tropic viruses crossed class barriers to infect cells of avian species but not insect, fish, or reptile cells.