Esqueletogênese em punaré (Thrichomys laurentinus- Rodentia, Echimyidae) / Skeletogenesis in punare (Thrichomys laurentinus - Rodentia, Echimyidae)

O objetivo deste estudo foi descrever o desenvolvimento do esqueleto do punaré (Thrichomys laurentinus). Para tanto, foram utilizados 11 embriões e 12 fetos em diferentes estágios de desenvolvimento, sendo divididos em 4 grupos de acordo com o período gestacional. As amostras foram obtidas no Centro de Multiplicação de Animais Silvestres da Universidade Federal Rural do Semi-Árido, Mossoró-RN, Brasil. Após fixados em formol (10%) ou glutaraldeído (2,5%), foi realizada a analise morfológica com auxílio de lupa, sendo as características macroscópicas fotodocumentadas. Análises de raios-x e coloração por alizarina red foram realizadas para melhor compreensão do desenvolvimento ósseo. Nas análises de raio-x os embriões não apresentaram nenhuma radiopacidade, ao contrário dos fetos que apresentavam radiopacidade gradual ao longo dos grupos. No grupo II houve aumento de radiopacidade na região da coluna vertebral e das regiões mandibular e maxilar. No grupo III a radiopacidade estava aumentada nos membros pélvicos, nas costelas e na região frontal e no grupo IV nos membros torácicos e nas regiões occipital, temporal e frontal do crânio. Tais características foram confirmadas pelas analises histológicas e pela técnica de Alizarina Red. Com isso podemos concluir que o conhecimento acerca da embriologia do sistema ósseo normal é fundamental para o entendimento dos efeitos adversos causados pela nutrição e uso de drogas durante o desenvolvimento.(AU)

The aim of this study was to describe the skeletogenesis in punaré (Thrichomys laurentinus). We used 11 embryos and 12 fetuses in different stages of development, allocated into 4 groups. Samples were obtained from the Multiplication Center of Wild Animals, at Federal Rural University of the Semi-Arid, Mossoro/RN, Brazil. After fixed in formalin (10%) or glutaraldehyde (2.5%) the morphological analysis was performed with a magnifying glass, and the macroscopic characteristics were photographed. Analysis of X-rays and alizarin red staining was made to better understand the development of bone structures. In x-ray analysis, it was possible to verify that the embryos showed no radiopacity, unlike fetuses that had gradual radiopacity along of the groups. In group II, there was an increase in radiopacity in the spine, mandibular and maxillary regions. In group III, the radiopacity was increased in the hind limbs, ribs and in the frontal region, and group IV showed higher radiopacity in the thoracic limbs and occipital, temporal and frontal skull. These characteristics were confirmed by histological and alizarin red analysis. We concluded that the knowledge of normal skeletal embryology is critical for understanding of adverse effects caused by nutrition and use of drugs during the development.(AU)

[Surveying limb shortening in obstetrical brachial plexus palsy]

Prior investigators have demonstrated the effectiveness of brachial plexus reconstructive surgery in neonates with obstetrical brachial plexus palsy. In the present study, we compared limb growth in a group of neonates underwent surgery with those who were subjected for surgery but refused. Totally, 55 neonates received treatment during a 10-year period were selected. They were assigned in 2 groups: 25 who could not achieve biceps flexion during the first 3 months and underwent reconstructive surgery [case group], and 30 neonates who had been subjected for reconstructive surgery but refused [control]. Finally, the intact and the injured limb were measured from acromion to the third finger. C5, C6, and C7 were the most common affected sites, while, nerve graft was the most common microscopic surgical approach. Limb shortening was 0-3 cm in operated as compared to 3-25 cm in nonoperated neonates [p<0.05]. Neonates who could not achieve biceps flexion during the first 3 months should be scheduled for reconstructive surgery, mainly with nerve grafting