RESUMEN
Caustic ingestion is one of the most life-threatening events in the pediatric age group, which requires the immediate management and subsequent treatment of its most significant complication, i.e. alterations in esophageal structure. We investigated whether melatonin could reduce the esophageal burn damage induced by sodium hydroxide. It was assumed that melatonin could be effective because of its function as a direct free radical scavenger, its antioxidative actions and its ability to diminish tissue hydroxyproline (HP) levels. Esophageal burns were induced in male rats by the administration of 10% sodium hydroxide. Lipid peroxidation (LPO) products were then measured at the following times: 0, 1, 6, 24, 48 and 72 hr after treatment. Tissue HP concentrations in the injured area were assessed at 14 days after the administration of sodium hydroxide. The groups received either systemic melatonin or normal saline. There were two, non-ischemic, sham control groups treated with or without melatonin. LPO products, malondialdehyde (MDA) and 4-hydroxyalkenal (4-HDA), increased immediately after the administration of sodium hydroxide; this indicates the participation of free radicals in the development of damage. Melatonin diminished the oxidative response and the amount of HP in the late phase of the lesion. Melatonin reduced oxidative damage in the early phase of the esophageal burns induced by sodium hydroxide.
Asunto(s)
Quemaduras Químicas/tratamiento farmacológico , Esófago/efectos de los fármacos , Melatonina/farmacología , Sustancias Protectoras/farmacología , Animales , Antioxidantes/farmacología , Quemaduras Químicas/etiología , Esófago/lesiones , Esófago/metabolismo , Hidroxiprolina/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Masculino , Malondialdehído/metabolismo , Ratas , Ratas Sprague-Dawley , Hidróxido de Sodio/toxicidadRESUMEN
It has been demonstrated that high concentrations of monosodium glutamate in the central nervous system induce neuronal necrosis and damage in retina and circumventricular organs. In this model, the monosodium glutamate is used to induce an epileptic state; one that requires highly concentrated doses. The purpose of this study was to evaluate the toxic effects of the monosodium glutamate in liver and kidney after an intra-peritoneal injection. For the experiment, we used 192 Wistar rats to carry out the following assessments: a) the quantification of the enzymes alanine aminotransferase and aspartate aminotransferase, b) the quantification of the lipid peroxidation products and c) the morphological evaluation of the liver and kidney. During the experiment, all of these assessments were carried out at 0, 15, 30 and 45 min after the intra-peritoneal injection. In the rats that received monosodium glutamate, we observed increments in the concentration of alanine aminotransferase and aspartate aminotransferase at 30 and 45 min. Also, an increment of the lipid peroxidation products, in kidney, was exhibited at 15, 30 and 45 min while in liver it was observed at 30 and 45 min. Degenerative changes were observed (edema-degeneration-necrosis) at 15, 30 and 45 min.
Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/enzimología , Aditivos Alimentarios/toxicidad , Enfermedades Renales/inducido químicamente , Glutamato de Sodio/toxicidad , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Inyecciones Intraperitoneales , Enfermedades Renales/patología , Peroxidación de Lípido/efectos de los fármacos , Pruebas de Función Hepática , Masculino , Ratas , Ratas WistarRESUMEN
HLA-A and HLA-B genes were typed by DNA sequencing in a mestizo population from Guadalajara, Jalisco, Mexico. Thirty-seven HLA-A and 51 HLA-B alleles were observed in 103 samples. The common typical Amerindian alleles (>5%) and haplotypes (>or=2.0%) found were A*02010101, *24020101, *310102, B*350101, and *4002, and A*310102-B*4002, A*240201-B*350101, and the typical European alleles were A*010101, *29010101, B*1402, B*180101, and A*020101-B*1402, A*020101-B*510101, and A*3002-B*180101. This reflects the blending of the two main parental populations of mestizos: Amerindian and Iberian. Mexicans were found to be relatively closer to the Portuguese than to Spaniards. This proximity may indicate a larger Portuguese influence in Mexicans than previously considered. Present data contribute to the understanding of the genetic structure in Mexico.
Asunto(s)
Frecuencia de los Genes , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Genética de Población , Antígenos HLA-A/clasificación , Antígenos HLA-B/clasificación , Haplotipos , Prueba de Histocompatibilidad , Humanos , México , Filogenia , Portugal , Análisis de Secuencia , EspañaRESUMEN
BACKGROUND: This study was designed to determine if the very potent antioxidant melatonin is able to reduce organ damage and improve energetic status in an in situ liver ischemia/reperfusion model. MATERIALS AND METHODS: Total hepatic ischemia was induced in rats by occlusion of the hepatic artery, portal vein, and bile duct. A portojugular shunt was inserted. After 60 min of ischemia, reperfusion was established for a period of 120 min. Rats were assigned to one group receiving systemic melatonin administration or to another receiving only normal saline. Variables were observed at preischemia, after 60 min of ischemia, and at 30, 60, and 120 min of reperfusion. RESULTS: Energy charge, measured as the arterial ketone body ratio, showed higher values in the melatonin group during the first 60 min of reperfusion. Rises in plasma nitrite, tumor necrosis factor (TNF)-alpha, aspartate aminotransferase, alanine aminotransferase, lipid peroxidation products, and inducible nitric oxide synthase (iNOS) expression were less severe with melatonin. Linear regression analysis demonstrated a significant correlation between nitrites and arterial ketone body ratio (R(2) = 0.2454). Bile production was higher with melatonin. Seven-day survival rates were 52% for control, 80% for melatonin, and 100% for sham groups. CONCLUSIONS: Exogenous melatonin is capable of preserving the functional and energetic status during ischemia/reperfusion which is associated with reduced concentrations of TNF-alpha and inhibited expression of iNOS and NO production. This improvement may be due to an adequate preservation of the hepatic mitochondrial redox status.
Asunto(s)
Antioxidantes/farmacología , Melatonina/farmacología , Óxido Nítrico/metabolismo , Daño por Reperfusión/tratamiento farmacológico , Factor de Necrosis Tumoral alfa/metabolismo , Ácido 3-Hidroxibutírico/sangre , Acetoacetatos/sangre , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Respiración de la Célula/efectos de los fármacos , Respiración de la Célula/fisiología , Metabolismo Energético/efectos de los fármacos , Metabolismo Energético/fisiología , Regulación Enzimológica de la Expresión Génica , Cuerpos Cetónicos/sangre , Hígado/irrigación sanguínea , Hígado/metabolismo , Masculino , Mitocondrias/metabolismo , Óxido Nítrico Sintasa/genética , Óxido Nítrico Sintasa de Tipo II , Nitritos/sangre , ARN Mensajero/análisis , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/mortalidad , Tasa de SupervivenciaRESUMEN
Background. Liver viability depends on blood flow rate, which varies among isolated perfused livers used in different studies. We aimed to identify the minimal blood flow capable of keeping the energy charge compatible with liver viability. Materials and methods. Isolated canine livers were assigned to different groups (n = 4) with blood flow rates of 0.5 (Group I), 1.0 (Group II), and 1.5 ml/g/min (Group III). Blood gases, hematocrit, and glucose were measured over 180 min. Nucleotides, serum osmolarity, and electrolytes were also measured. Morphological changes were recorded at the end of each experiment. Results. Acid-base balance was better in livers from Group III. Electrolytes, osmolarity, hematocrit, and glucose showed no differences. Higher energy charges correlated with higher blood flow rates. On histopathology, there was evidence of more hydrostatic pressure-related changes in Group III, with no difference in necrosis or inflammatory-related alterations. Conclusions. (1) Energy charge correlates strongly with blood flow rate. (2) A rate of 1.5 ml/g/min allows for a better electrolyte, osmolarity, and acid-base balance. (3) Morphological analysis is not a sensitive predictor of organ viability as assessed by energetic potential. (4) The minimal blood flow rate required to attain an energy charge above 0.75 is 1.33 ml/g/min.
Asunto(s)
Velocidad del Flujo Sanguíneo/fisiología , Circulación Hepática/fisiología , Hígado/metabolismo , Equilibrio Ácido-Base , Adenosina Monofosfato/metabolismo , Animales , Perros , Metabolismo Energético , Técnicas In Vitro , Hígado/patología , Masculino , Consumo de Oxígeno , PerfusiónRESUMEN
The characteristics of a model of urolithiasis in the bladder of male Wistar rats were evaluated. Two techniques were compared: one knot of suture material through the bladder wall, or 15-throw knots inside the bladder. Rats were randomly assigned to one of six groups, according to the technique and suture material used (polyester, silk, or chromic catgut). An excretory urogram was performed at days 30, 60, and 90. At the moment of positive radiographic diagnosis, animals were sacrificed and stones were obtained. All rats were sacrificed at day 90 regardless of the x-ray results. Variables evaluated were average days to a positive urogram, average weight of all uroliths, and percentage of animals developing urolithiasis throughout the study. There were no statistical differences between groups for the average weight of stones, which ranged from 0.008 to 1.502 g for individual cases. All three materials were more lithogenic with the 15-throw knot inside technique. No significant differences were detected for lithogenesis criteria between suture materials. X-ray dispersion spectroscopy evidenced calcium phosphate composition of two stones from chromic catgut, and magnesium phosphate composition of two stones from chromic catgut, two from silk, and two from polyester. Neo-epithelization over the suture was confirmed microscopically in bladders with the one-throw technique. We conclude that (1) this is an effective model of urolithiasis, with predictability in time, composition, and amount of stone formation; (2) the presence of more suture material inside the bladder is more lithogenic; and (3) excretory urograms are highly sensitive and specific for the noninvasive diagnosis of bladder urolithiasis.