Usos de membrana amniótica en patología ocular pediátrica / Use of amniotic membrane in childhood ocular disease

Introducción: La membrana amniótica (MA) posee varias propiedades clínicas que la hacen útil en el tratamiento de diferentes patologías. El principal efecto clínico es que permite la epitelización de los tejidos, favorece el crecimiento, adhesión y diferenciación de las células epiteliales, además de prevenir su apoptosis, reduciendo la cicatrización. Objetivo: Describir la utilidad de la membrana amniótica como alternativa en el tratamiento de la superficie ocular. Son abordados tópicos como las diferentes formas de obtención, preparación y conservación de la misma, así como sus mecanismos de acción y aplicaciones. Resultados: En el Servicio de Oftalmología del Hospital de Pediatría J. P. Garrahan se usaron 429 membranas amnióticas en 294 pacientes desde el año 2002 hasta octubre 2014 para el tratamiento de distintas patologías oculares. Los pacientes estudiados presentaron reducción de la inflamación, vascularización y mejor cicatrización. Conclusión: la MA es en la actualidad una alternativa en el tratamiento de patologías de difícil manejo que no responden a las terapias médicas convencionales. Sin embargo, su empleo deberá ser racional, para evitar falsas expectativas de considerarla como panacea en toda patología corneal o conjuntival (AU)

Introduction: Amniotic membrane has several clinical properties rendering it useful in different pathologies. Its main clinical effect is the epithelization of tissue, favoring growth, adhesion and differentiation of epithelial cells as well as prevention of apoptosis and reduction of scarring. Objective: To determine the usefulness of amniotic membrane as an alternative for ocular surface treatment. Issues such harvesting techniques, preparation, and storage of the amniotic membrane, as well as mechanisms of action and use are discussed. Results: At the Department of Ophthalmology of the Pediatric Hospital J. P. Garrahan 429 amniotic membranes were used in 294 patients between 2002 and October 2014 for the treatment of different eye pathologies. The patients studied presented with reduced inflammation and better vascularisation and scarring. Conclusion: Amniotic membrane is currently a treatment option in difficult-to-treat pathologies that do not respond to conventional therapies. Nevertheless, it should be used rationally to avoid unrealistic expectations considering it the panacea for all corneal or conjunctival pathologies (AU)

Modeling the structural basis of human CCR5 chemokine receptor function: from homology model building and molecular dynamics validation to agonist and antagonist docking.

This article describes the construction and validation of a three-dimensional model of the human CCR5 receptor using a homology-based approach starting from the X-ray structure of the bovine rhodopsin receptor. The reliability of the model is assessed through molecular dynamics and docking simulations using both natural agonists and a synthetic antagonist. Some important structural and functional features of the receptor cavity and the extracellular loops are identified, in agreement with data available from site-directed mutagenesis. The results of this study help to explain the structural basis for the recognition, activation, and inhibition processes of CCR5 and may provide fresh insights for the design of HIV-1 entry blockers.

Simultaneous determination of SO(2), NO and NO(2) in air by differential pulse polarography.

The method of Garber and Wilson for SO(2) determination has been tested on real samples of air. The results demonstrate the possibility of simultaneous determination of SO(2), NO and NO(2) in the sample. Detection limits as low as 7 mul/m(3) for SO(2) and about 50 mul/m(3) for nitric oxides can be reached.

Massive colonic variceal bleeding secondary to abnormal splenocolic collaterals: report of a case.

Even in the absence of demonstrable esophagogastric varices in the cirrhotic patient, a diagnosis of variceal bleeding from unusual sites should be entertained in the differential diagnosis of massive lower gastrointestinal hemorrhage. The varices may reflect the increased pressure in the superior or inferior mesenteric systems or in the splenic system through abnormal splenocolic anastomoses. This case has the unique feature of bleeding from varices interposed between the splenic and inferior mesenteric venous systems, as opposed to the previously described cases of varices draining directly into a portosystemic conduit.