Structural Chromosomal Alterations In Hyla Albopunctata And Aplastodiscus Perviridis (anura, Hylidae) From The Morro Do Ferro Region Of Minas Gerais

Metaphase chromosomes were analyzed in Aplastodiscus perviridis from the locations: Morro do Ferro (MG), Serra da Bocaina (SP), Botucatu (SP), and in Hyla albopunctata found at: Morro do Ferro, Botucatu, and Campinas (SP). A significant quantity of metaphases with structural alterations were found in the Morro do Ferro population. These alterations were classified as: decondensation, condensation, breaks, gaps, deletions and acentric fragments. Breaks, deletions and fragments were the most frequent alterations and a great number of these occurred near centromeric heterochromatin. The frequency of altered metaphases varied among individuals in all populations studied. The majority of the alterations can probably be attributed to the high level of natural radiation at Morro do Ferro.18219119

Comparative Ultrastructural Analysis Of Different Regions Of Two Digital Flexor Tendons Of Pigs

Tendons are parallel arrays of collagenous fibers which are specialized in resisting and transmitting tensile forces. In this work we examined the structure of the superficial digital flexor tendon (SDFT) and the deep digital flexor tendon (DDFT) of pigs, which are considered "wrap around" tendons and so receive compression and tension forces. In both tendons, fibrocartilaginous areas were observed in the regions subjected to compression plus frictional loading. Histological and ultrastructural analyses of the tensional region showed an extracellular matrix (ECM) rich in collagen bundles, that were all arranged in the same direction. Fibroblasts were seen closely associated with the collagen bundles. Chondrocyte-like cells and high levels of glycosaminoglycans (GAGs) were observed in the compressional regions. The collagen bundles in the compressional region were arranged in several directions and were associated with proteoglycans (PGs). 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O status taxonômico de Hyla cochranae Mertens e recaracterização de Aplastodiscus A. Lutz (Anura, Hylidae) The taxonomic status of the Hyla cochranae Mertens and recharacterization of Aplastodiscus A. Lutz (Anura, Hylidae)

<abstract language="eng">Hyla cochranae Mertens, 1952 is revalidated and the description of the tadpole and vocalization is provided. Based on external morphology, the genus Aplastodiscus A. Lutz, 1950 is recharacterized and a redescription of A. perviridis A. Lutz, 1950 is given. New data on geographical distribution and biology of both species are provided