Fine-scale spatial genetic structure of eight tropical tree species as analysed by RAPDs.

The fine-scale spatial genetic structure of eight tropical tree species (Chrysophyllum sanguinolentum, Carapa procera, Dicorynia guianensis, Eperua grandiflora, Moronobea coccinea, Symphonia globulifera, Virola michelii, Vouacapoua americana) was studied in populations that were part of a silvicultural trial in French Guiana. The species analysed have different spatial distribution, sexual system, pollen and seed dispersal agents, flowering phenology and environmental demands. The spatial position of trees and a RAPD data set for each species were combined using a multivariate genetic distance method to estimate spatial genetic structure. A significant spatial genetic structure was found for four of the eight species. In contrast to most observations in temperate forests, where spatial structure is not usually detected at distances greater than 50 m, significant genetic structure was found at distances up to 300 m. The relationships between spatial genetic structure and life history characteristics are discussed.

Encuesta de actitud: los médicos pediatras y los residentes de pediatría frente a la alimentación normal del niño en el primer año de vida, en un hospital pediátrico de referencia / Survey of attitude: doctors pediatricians and pediatric residents compared to the normal feeding of the child in the first year of life, in a pediatric hospital reference

Se realizó una encuesta a 69 residentes de clínica pediátrica y a 10 médicos de planta del Hospital Garrahan, con el objetivo de evaluar la actitud de los mismos frente a la alimentación del niño sano en el primer año de vida, de acuerdo a la coherencia de sus recomendaciones con respecto a las normas existentes. La encuesta consistia en 9 preguntas del tipo multiple choice sobre distintos temas habituales de alimentación del niño sano y una última pregunta para determinar cuales eran las fuentes de información nutricional más utilizadas por médicos. El 50 por ciento del total de médicos pudo responder solo 5 preguntas en forma correcta, es decir, en forma coherente con las normas existentes. Si bien los médicos de planta evidenciaron un porcentaje mayor de respuestas correctas en la mayoría de las preguntas, esta diferencia con respecto a los residentes, no fue estadísticamente significativa (chi cuadrado p 2). La nutricionista es la fuente de información más consultada por todos los médicos en general (25 por ciento), le siguen en orden los conocimientos transmitidos por otros médicos (21 por ciento) y las clases dictadas en el hospital (20 por ciento). Estos resultados transforman a la docencia dentro del hospital, especificamente a las clases especiales, en un potencial ámbito para transmitir información nutricional a los futuros médicos pediatras. En vista de la considerable falta de adherencia a ciertas normas y temas básicos de nutrición infantil normal, los médicos deberían ser estimulados para mejorar la calida de la eficiencia de sus consejos nutricionales. Dado que las nutricionistas ocupados el primer lugar entre las fuentes de consulta de los médicos según los resultados arrojados por éste y otros trabajos, no podemos eludir la responsabilidad de tomar un rol activo en la difusión de la información nutricional a los médicos pediatras.

Familial autoimmune enteropathy with circulating anti-bullous pemphigoid antibodies and chronic autoimmune hepatitis.

In a family of four children (two boys and two girls), the two brothers had severe, protracted watery diarrhea beginning at 2 and 3 weeks of life, respectively. Duodenal mucosa in both patients showed total villous atrophy and severe inflammatory infiltration of the entire bowel. The first patient also had lymphoid cell infiltration of the pancreas and died at 6 weeks of age. The second boy is alive at 2 years of age and is immunocompetent, but still receives total parenteral nutrition. Indirect immunofluorescence studies revealed circulating antibodies to enterocytes, smooth muscle, thyroid, and islet cells. Bullous pemphigoid antibodies (230 and 180 kd), specific for hemidesmosomal proteins and usually associated with a subepidermal blistering skin disease, were detected by direct and indirect immunofluorescence studies and by Western immunoblot. A diagnosis of autoimmune hepatitis was made, based on evidence of chronic active hepatitis and circulating anti-smooth muscle antibody. Immunosuppressive treatments induced partial clinical remission of the diarrhea but no resolution of the small bowel injury. At 16 months of age, remission of the diarrhea occurred, but persistent autoimmune hepatitis led us to maintain treatment with prednisone and azathioprine, and later with cyclosporine. In this child, as in other patients with autoimmune disease, the link between autoantibodies and organ damage remains uncertain but immunosuppressive treatment is indicated.

Genetic diversity among wild and cultivated populations of Hevea brasiliensis assessed by nuclear RFLP analysis.

Restriction fragment length polymorphism was assessed in wild and cultivated populations of Hevea brasiliensis using random probes from an Hevea nuclear library. One-hundred-and-sixty-four individuals were surveyed, and the results discussed in the light of previous work performed on isozyme variation. Both studies show that germplasm collections have led to an effective enrichment of the genetic resources available for Hevea breeding, and that cultivated clones have conserved a relatively high level of polymorphism, despite their narrow genetic base and their high level of inbreeding. An equivalent level of polymorphism is revealed by random nuclear probes and isozymes. However, the genetic structuring of the diversity appears more striking using RFLP markers. Wild accessions can be divided into three genetic groups according to their geographical origin. The present results are an essential guide to the incorporation of wild material in breeding schemes.

Estudio epidemiológico-clínico de las intoxicaciones registradas en los Hospitales Rafael Hernández, Dionisio Arrocha y José Obaldía de la provincia de Chiriquí durante el año 1993 / Clinical epidemiological study of the intoxation registed in Rafael Hernandez, Dionicio Arrocha and Jose Olbaldia Hospitals in the Province of Chiriqui During 1993

Investigación descriptiva - retrospectiva que forma parte de una serie de estudios realizados sobre las intoxicaciones registradas en los principales hospitales del país. Este informe incluye los datos registrados durante el año 1993 en los hospitales Rafael Hernández, Dionisio Arrocha y José D. Obaldía de la provincia de Chiriquí. En la Población adulta se registraron 438 casos, mientras que en los niños se atendieron 201 casos, Los agentes zoológicos (ofidios) causaron la mayoría de las intoxicaciones en ambas poblaciones de pacientes. En la población adulta se registraron 91 casos de intoxicaciones por plaguicidas. De éstos 46 ocurrieron con insecticidas (25 con organofosforados y 16 con carbamatos, uno con un organoclorado, otro con un piretroide, otro con una combinación de organofosforado con piretroide y dos con agentes no especificados); 42 ocurrieron con herbicidas (37 con paraquat, 3 con clorofenoxi, uno con un diurón y uno con un agente no especificado). La mayoría de los casos ocurrió por exposición ocupacional, seguidos del intento suicida y de la causa accidental. En la población infantil se registraron 10 casos. De éstos, 6 ocurrieron por insecticidas (organofosforados, carbamatos, piretroides y organoclorados) y 4 con herbicidas (paraquat). Todos evolucionaron satisfactoriamente. De las 14 defunciones registradas en este estudio, 10 ocurrieron en la población adulta debido a la intoxicación por paraquat, lo que representó el 76.9 por ciento de las muertes por intoxicación

Morphological aspects of early and late collagen degradation in granulation tissue.

A sequential histologic, ultrastructural and immuno pathologic study was carried out in the Selye's inflammatory pouch model to observe extracellular matrix and cellular changes during granulation tissue formation. Besides changes involving different components of the connective tissue, it was observed that collagen resorption occurred under a biphasic process. At an early phase (3rd to 15th day), in which exudative inflammatory changes predominated, signs of collagen synthesis and degradation were seen simultaneously. Extracellular breakdown and internalization of collagen fragments within fibroblasts and myofibroblasts were observed. Later on (30th to 60th day), changes affecting collagen had a different ultrastructural appearance. Collagen fragmentation, focal "lytic" and "electron dense" changes occurred in the extracellular space specially at the periphery of fibroblasts, myofibroblasts and smooth muscle cells. Collagen degradation, thus seems to be a continuous process in granulation tissue, occurring with different morphologies at different times.

Elastin in alcoholic liver disease. An immunohistochemical and immunoelectron microscopic study.

Increased elastic stained material has been described in fibrotic and cirrhotic liver processes. The aim of this work was to follow the development and distribution of elastic fibers from 48 chronic alcoholic patients. Patients were scored for fibrosis as 0, without fibrosis or minimal (n = 5); 1, incipient or early fibrosis (n = 9); 2, fibrosis or incomplete cirrhosis (n = 12); and 3, cirrhosis (n = 22). Elastica staining was performed by orcein, resorcin-fuchsin and iron hematoxylin and confirmed by immunofluorescence staining with an anti-human elastin antibody (Institut Pasteur). Electron microscopy of representative cases of each group and electron microscopy of immunolabelled elastin (n = 5) were also performed. In early alcoholic fibrosis, oxytalan fibers were pointed out in terminal hepatic veins and in Disse space. In fibrous portal extensions and cirrhotic internodular septa, oxytalan and elaunin fibers represented the major elastin components in association with the alcoholic liver fibroplasia. Immunostaining with anti-elastin Ab exhibits the same distribution as with histochemical methods in portal and septal zones. Electron microscopy confirmed abundant microfibrillar bundles between collagen fibers that mesh and are in continuity with elaunin fibers. Immunoelectron microscopy confirmed elastin deposits in the amorphous material and in association with the microfibrillar material in the portal and septal zones and disclosed elastin even in the thin strands of fibrotic tissue. In conclusion, elastogenesis, mainly represented by oxytalan and elaunin fibers, develops in alcoholic disease and takes part, with collagen deposits, in the fibrotic process.