ABSTRACT
The congenital portosystemic shunt is an uncommon disease with severe complications if not treated. This rare cause of hypoxemia was first described by John Abernethy in 1973. There are two types: type I (termino-lateral shunt), in which there is total absence of the intrahepatic portal flow, and type II (latero-lateral shunt), in which the portal flow is partially preserved. We present the case of a 6-year-old girl with chronic hypoxemia history since 4 and a half years of age, showing progressive dyspnea, who was referred to the Pediatric Pulmonary Division with the diagnosis of central cyanosis. An Echo-Doppler in the portal venous system was performed, reporting agenesis of the principal portal vein. This finding was corroborated by an angiography of the portal and mesenteric arteriovenous system. The study was completed with a portosplenography, which confirmed the diagnosis of type Ib Abernethy malformation. The type I Abernethy malformation is more common in females, shows up in different ways and is treated with liver transplantation. On the other hand, type II Abernethy malformation shows a variable portal circulation and has a better prognosis than type I. Dyspnea when exercising and central cyanosis should be considered to make a differential diagnosis of cardiorespiratory disease at a pediatric age.
Subject(s)
Cyanosis/etiology , Portal Vein/abnormalities , Vascular Malformations/diagnosis , Child , Female , Humans , Vascular Malformations/complicationsABSTRACT
El shunt porto sistémico congénito es una causa rara de hipoxemia y una patología muy poco frecuente con complicaciones severas si no es tratada. Fue descrito por primera vez por John Abernethy en 1793. Existen dos tipos: tipo I (shunt termino lateral) en el que hay ausencia total del flujo portal intrahepático y tipo II (shunt latero lateral) con flujo portal parcialmente conservado. Se presenta el caso de una niña de 6 años de edad con antecedente de hipoxemia crónica desde los 4 años y medio de vida, acompañado de disnea progresiva, quien fue referida a la unidad de neumología pediátrica con diagnóstico de cianosis central. Entre los estudios diagnósticos considerados se realizó ecografía doppler del sistema venoso portal, evidenciándose ausencia de vena porta principal; además se realizó angiotomografía del sistema arterio-venoso portal y mesentérico, confirmándose la agenesia de vena porta. Se completó el estudio con una porto-esplenografía que confirmó el diagnóstico de malformación de Abernethy tipo I b. La malformación de Abernethy tipo I es más frecuente en el sexo femenino, tiene varias formas de presentación y el tratamiento es el trasplante hepático. En la malformación de Abernethy tipo II la circulación portal es variable y tiene mejor pronóstico que la de tipo I. La disnea al ejercicio y la cianosis central es una forma de presentación que debemos tener en cuenta en el diagnóstico diferencial de la patología cardiorrespiratoria en la edad pediátrica.
The congenital portosystemic shunt is an uncommon disease with severe complications if not treated. This rare cause of hypoxemia was first described by John Abernethy in 1973. There are two types: type I (termino-lateral shunt), in which there is total absence of the intrahepatic portal flow, and type II (latero-lateral shunt), in which the portal flow is partially preserved. We present the case of a 6-year-old girl with chronic hypoxemia history since 4 and a half years of age, showing progressive dyspnea, who was referred to the Pediatric Pulmonary Division with the diagnosis of central cyanosis. An Echo-Doppler in the portal venous system was performed, reporting agenesis of the principal portal vein. This finding was corroborated by an angiography of the portal and mesenteric arteriovenous system. The study was completed with a portosplenography, which confirmed the diagnosis of type Ib Abernethy malformation. The type I Abernethy malformation is more common in females, shows up in different ways and is treated with liver transplantation. On the other hand, type II Abernethy malformation shows a variable portal circulation and has a better prognosis than type I. Dyspnea when exercising and central cyanosis should be considered to make a differential diagnosis of cardiorespiratory disease at a pediatric age.
Subject(s)
Child , Female , Humans , Portal Vein/abnormalities , Cyanosis/etiology , Vascular Malformations/diagnosis , Vascular Malformations/complicationsABSTRACT
It has been postulated that chronic administration of antidepressant drugs induces delayed structural and molecular adaptations at glutamatergic forebrain synapses that might underlie mood improvement. To gain further insight into these changes in the cerebral cortex, rats were treated with fluoxetine (flx) for 4 weeks. These animals showed decreased anxiety and learned helplessness. N-methyl-d-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptor subunit levels (NR1, NR2A, NR2B, GluR1 and GluR2) were analysed in the forebrain by both western blot of homogenates and immunohistochemistry. Both methods demonstrated an upregulation of NR2A, GluR1 and GluR2 that was especially significant in the retrosplenial granular b cortex (RSGb). However, when analysing subunit content in postsynaptic densities and synaptic membranes, we found increases of NR2A and GluR2 but not GluR1. Instead, GluR1 was augmented in a microsomal fraction containing intracellular membranes. NR1 and GluR2 were co-immunoprecipitated from postsynaptic densities and synaptic membranes. In the immunoprecipitates, NR2A was increased while GluR1 was decreased supporting a change in receptor stoichiometry. The changes of subunit levels were associated with an upregulation of dendritic spine density and of large, mushroom-type spines. These molecular and structural adaptations might be involved in neuronal network stabilization following long-term flx treatment.
Subject(s)
Antidepressive Agents/pharmacology , Fluoxetine/pharmacology , Gene Expression Regulation/drug effects , Glutamic Acid/physiology , Neuronal Plasticity/drug effects , Prosencephalon/drug effects , Receptors, AMPA/biosynthesis , Receptors, N-Methyl-D-Aspartate/biosynthesis , Animals , Anxiety/drug therapy , Behavior, Animal/drug effects , Dendritic Spines/drug effects , Dendritic Spines/metabolism , Helplessness, Learned , Intracellular Membranes/drug effects , Intracellular Membranes/metabolism , Male , Microsomes/drug effects , Microsomes/metabolism , Neurons/drug effects , Neurons/metabolism , Neurons/ultrastructure , Post-Synaptic Density/drug effects , Post-Synaptic Density/metabolism , Prosencephalon/metabolism , Rats , Rats, Sprague-Dawley , Receptors, AMPA/genetics , Receptors, N-Methyl-D-Aspartate/genetics , Synaptic Membranes/drug effects , Synaptic Membranes/metabolismABSTRACT
Since its introduction two decades ago, the isolated brain stem-spinal cord preparation of neonatal rodents has been the preferred method used to reveal the mystery underlying the genesis of the respiratory rhythm. Little research using this in vitro approach has focused on the study of the central respiratory chemosensitivity. Some unexpected findings obtained with the brain stem-spinal cord preparation have added new questions that challenge our previous theoretic framework. Some of these findings are addressed here.
