Human platelet-specific antigens frequencies in the Argentinean population.

The frequencies of several human platelet antigens (HPAs) vary between different populations and are a major determinant for the prevalence of HPA alloimmunization and its clinical associated entities. The aim of this study was to characterize the allele frequencies of seven HPA systems in two different ethnic groups from the Argentinean city of Rosario, the major population and a minority Amerindian group recently arrived from the north of the country, the Tobas. A total of 192 healthy unrelated individuals from blood donors and hospital staff from the Hospital Italiano Garibaldi and 27 unrelated Toba Amerindians were genotyped for HPA-1, -2, -3, -4, -5, -6 and -15 systems by polymerase chain reaction with sequence specific primers (PCR-SSP). The present data showed that the distribution of the HPA alleles among Argentineans from Rosario is quite similar to that reported among Europeans. The frequencies seen in Tobas, although limited by the small number of aboriginal samples studied, are similar to those reported for other Amerindians populations. Statistically significant differences were found for the genotype distribution of HPA-1, -3, -5 and -15 between both groups, indicating important differences in the potential risk of HPA alloimmunization associated to transfusion and pregnancy. The study of these polymorphisms represents the first step in the elucidation of pathological conditions that are underdiagnosed in our population. It allowed us to establish a panel of characterized blood donors necessary for the serological work out and as a source for compatible platelets transfusion.

Objetivos conceptuales y metodológicos de la investigación histológica

El artículo define los objetivos de la histología humana necesarios para describir, con instrumentos y técnicas amplificantes, el cuerpo humano en los distintos estados de salud y la nueva orientación de la histología vinculada a la ingeniería tisular.Dichos objetivos, conceptuales y metodológicos, deben estar presentes en los profesionales sanitarios que quieran abordar cualquier protocolo de investigación médica en el que este presente la investigación histológica.(AU)

[Assessment of the impact of the biological rodenticide Biorat in populations of rodents settled in several crops of the Republic of Costa Rica]. / Evaluación del impacto del biorrodenticida Biorat en poblaciones de roedores establecidos en varios cultivos en la República de Costa Rica.

The impact of biological rodenticide Biorat on populations of rodents settled in some crops was determined; these crops are highly infested with Sigmodon hispidus, a very common vector in various Central American countries. The trapping technique and the appraisal of damages allowed to calculate the index of infestation which ranged from 75 to 90 percent in three crops. Twenty for to 36 kg of BIORAT were applied to 6 ha planted with Cucumis sativus (cucumber), Ipomoea batata (sweet potato) and Ananas comusus (pineapple). This action brought about that the rodent population in such crops reduced the potential damage and consequently, index of infestation was reduced by 94.6 to 98%; therefore, the residual population left amounted from 2 to 3.5%, meaning that damages were under the economic threshold. Generally speaking, the results were similar to those of other countries.

[Surface microscopic patterns of an experimental model of surgically induced carcinogenesis]. / Patrones microscópicos de superficie de un modelo experimental de carcinogenesis inducido quirúrgicamente.

An experimental model of carcinogenesis is developed by authors, using internal urinary diversion in Wistar rats. Results show the transformation of normal digestive pattern, discovering proliferative-inflammatory changes at the first time which after go to an histiotypical tumorous pattern. They conclude at the carcinogenicity of the presented surgical model and is described the evolution of the superficial morphological pattern during the tumorigenic process.

[Effects of laser radiation on the periodontium. An animal model approach. Effects of usual radiation dosage]. / Efectos de la radiación láser sobre el periodonto. Aproximación en un modelo animal. Efecto de las dosis habituales de irradiación.

Twenty four albino mice of forty days old were selected. Twelve forty days old albino mice were irradiated with a Helium-Neon laser source, dose of 10.50566 Jul/cm2. They were divided in two groups according to time of animal sacrifice (immediately after irradiation and ten days after). As control were used twelve mice using the same time as the experimental groups, but without radiation. T.E.M. ultrathin sections showed alteration only in the conjunctiva and in the bone tissues, but not in the epithelial tissue. The bone showed two osteocyte population according to their response to irradiation. The first population showed characteristic comparable with the controls, and the second showed alterations suggestive of a degenerative process. The connective tissue also showed two fibroblasts populations, the first showed signs of a big synthesizing activity, and the second, degenerative signs. The first fibroblast population appeared in the animals sacrificed immediately after irradiation.

Magnets in guitarfish vestibular receptors.

Black magnetic particles are intermixed with white crystalline otoconia in the inner ear gravity receptors of a saltwater ray. Their size and composition suggest that they are multidomains of magnetite-ilmenite.

[Comparative ultrastructural study of the epithelial stromal junction in the prostatic gland]. / Estudio ultraestructural comparado de los E.S.J. en la glándula prostática.

In this paper, the authors carry out a comparative study of the structures adjacent to the alveolar periphery of the prostate-glands of men, dogs and bulls. In the three cases an E.S.J. (Epithelial-Stromal-Junction) similar to that described in the mammary gland and characterized in the first two cases by the existence of four, ultrastruct strata, consisting of the basal lamina, the somas of the adjacent fibroblasts and their cytoplasmic expansions as well as the arrangement of the intercellular, collagen microfibrils, was found to exist in this gland. In the case of the bovine prostate gland, the structural organization of the E.S.J. was basically characterized by the structural arrangement of the collagen microfibrils. The structures described constitute models on which to base future research on the hyperplastic and neoplastic processes of the prostate gland.