Neuronal plasticity of the enteric nervous system is correlated with chagasic megacolon development.

Chagas' disease is one of the few functional gastrointestinal disorders for which a causative agent has been identified. However, some pathological aspects of the chagasic megasyndromes are still incompletely understood. Chagasic megacolon is characterized by an inflammatory process, organ dilatation and neuronal reduction in both plexuses of the enteric nervous system (ENS). Although some studies on the ENS in Chagas' disease have been performed, the process of neuronal destruction and neuronal regeneration still remains unclear. Our hypothesis is that the regeneration process of the ENS may be involved with the mechanisms that prevent or retard organ dilatation and chagasic megacolon development. For that reason, we evaluated the neuronal regeneration with the marker GAP-43 in the colon's neuronal plexuses from chagasic patients with megacolon, and from non-infected individuals. Visual examination and quantitative analysis revealed an increased neuronal regeneration process in the dilated portion from chagasic patients when compared with the non-dilated portion and with non-infected individuals. We believe that this increased regeneration can be interpreted as an accentuated neuronal plasticity that may be a response of the ENS to avoid megacolon propagation to the entire organ and maintain the colon functional innervation.

Cephalic duodenopancreatectomy in the treatment of a bleeding duodenal ulcer in a pancreas recipient: a case report.

Pancreas transplantation is currently the only known therapy to restore glycemic metabolism in type 1 diabetic patients. Its most prevalent indication is in association with kidney transplantation (simultaneous pancreas and kidney transplantation SPK) for patients with type 1 diabetes mellitus (DM1) and nephropathy, who are under dialysis treatment. Surgical reinterventions, especially those resulting from complications of bladder exocrine pancreatic drainage, are associated with considerable morbidity and mortality. In this report, we present a clinical case of a 31-year-old Caucasian man with DM1 from 12 years of age and hemodialysis for 2 years before undergoing SPK 2 years prior. He then developed massive hematuria owing to a bleeding duodenal graft ulcer. The use of a segmental pancreatic technique with pancreaticocystostomy for exocrine pancreatic drainage allowed the maintenance of the graft and an euglycemic state in the patient, free of exogenous insulin.

Neurochemical coding of the enteric nervous system in chagasic patients with megacolon.

Neuronal destruction has been considered the hallmark of pathogenic mechanisms in chagasic megacolon. Characterization of neuropeptides in the enteric nervous system from chagasic patients with megacolon could elucidate some aspects of the development of this syndrome. In the present work we demonstrate the changes in expression of neuropeptides and neurochemical markers present in neuronal plexuses from the colons of chagasic patients with megacolon. Sections of frozen tissue samples were immunohistochemically labeled for anticalretinin, cChaT, substance P, VIP, NOS, and NPY. Immunoreactivity was observed using a confocal microscope. Our results demonstrate that in chagasic patients with megacolon, inhibitory motor neurons (VIP and NOS immunoreactive) are preferentially destroyed by Trypanosoma cruzi and/or the inflammatory process. These results suggest a selective destruction of enteric neurons in the colon of chagasic patients with megacolon, pointing to an important discovery in the mechanism of pathogenesis of Chagas' disease.

Congenital achalasia: facts and fantasies.

Achalasia, a poorly relaxing lower esophageal sphincter, produces a functional obstruction and the expected symptoms of dysphagia, regurgitation and eventually weight loss. The cause of achalasia remains largely unknown in Western countries, Chagas' disease being the most frequent etiology in Brazil. We report on two sets of monozygotic male twins with typical manifestations of achalasia. The majority of authors attribute a limited contribution unless achalasia is related to a multisystem disorder, like the triple-A or Allgrove's syndrome, an autosomal recessive disease characterized by the triad of adrenocorticotropic hormone (ACTH) resistant adrenal insufficiency, achalasia and alacrima. The four cases reported demonstrated the genetic influence of achalasia in patients without multisystem disorders. We believe that idiopathic achalasia is a syndrome with similar clinical, pathological, radiological and manometric evolution, but with a great variety of etiological agents, one of them being the congenital form.

[Dispersion pattern of saline indicator on canine left ventricle (author's transl)]. / Padrão de dispersão de indicador salino no ventrículo esquerdo de cães

The cardiac output evaluation is usually realized through indicator dilution techniques and this principle was applied to ventricular volume measurements. However this approach has been criticized by several workers. Based on the recently developed association of indicator dilution method with intraventricular impedance recording to cardiac output determinations, the present investigation was designed to analize the dipersion pattern of saline solution within the ventricle. Three bipolar eletrodes were placed in different positions on the left ventricle in order to record the duration in seconds, for the saline to reach these positions. The detection of the saline was done through conductibility changes at the eletrodes ends. The results indicate a time duration smaller to the indicator dispersion than those of the diastole duration, simultaneously measured.