Navegando por Autor "LIMA, Rafael Rodrigues"

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Acesso aberto (Open Access)
Anatomical and histological characteristics of teeth in agouti (Dasyprocta prymnolopha Wagler, 1831)
(2013-12) SILVA, Daiane Claydes Baia da; FAGUNDES, Nathália Carolina Fernandes; TEIXEIRA, Francisco Bruno; PENHA, Nelson Elias Abrahão da; SANTANA, Luana de Nazaré da Silva; OLIVEIRA, Ana Cristina Mendes de; LIMA, Rafael Rodrigues
The agouti species Dasyprocta prymnolopha (D. prymnolopha) is a medium-sized rodent, diurnal, and characteristic of northeastern Brazil, south of the Amazon. Several studies have been made on these rodents. However, there is a lack of analysis of masticatory system, in particular morphology of the teeth. Thus, this research seeks to describe anatomical and histological aspects of the agouti teeth. For this purpose, we used adult agouti, in which measurements and descriptions of teeth and dental tissues were made. It was observed that the dental arch of D. prymnolopha comprises of twenty teeth, evenly distributed in the upper and lower arch, being inferior teeth larger than their corresponding higher. The incisors are larger, and between the posterior premolars and molars, there is a gradual increase in length in the anterior-posterior arch. In microscopic examination, a prismatic appearance was observed consisting of enamel prisms arranged in different directions, behind the enamel and dentin with standard tubular dentinal tubules with variable diameter and far between, also showing a sinuous path from the inner portion to the junction with more superficial enamel. Morphological analysis of dental tissues showed that an enamel with structural organization adapted to the act of chewing and high impact dentin compatible with standard tubular function resilience and mechanical damping of masticatory forces, as found in larger animals, confirming the understanding of eating habits that define much of its ecological functions within the ecosystem they inhabit.
Acesso aberto (Open Access)
Ativação microglial, lesão da substância branca e expressão de Nogo-A em ratos submetidos à isquemia estriatal
(Universidade Federal do Pará, 2012-05-10) LIMA, Rafael Rodrigues; LEAL, Walace Gomes; http://lattes.cnpq.br/2085871005197072
The objective of this investigation was to evaluate the degenerative pattern of several white matter tracts after striatal ischemic injury, correlating degenerative process standards with the microglial activation and expression of Nogo-A. For this purpose, focal ischemia was induced with stereotactic injection of endothelin in striatum of adult rats, and only in the control animals injected with sterile saline. The animals were perfused 3, 7, 14 and 30 days after ischemia. The brain removed, postfixed, cryoprotected, cut into cryostat sections obtained and submitted to immunohistochemical investigation with the following antibodies: anti-GFAP (1:2000, Dako), anti-Tau-1 (1:500, Chemicon), Anti-MBP (1:100, Chemicon International), Anti-Nogo-A (1:100, Invitrogen), Anti-Iba1 (1:1000, WAKO), ED1 (1:500, Serotec) and Anti-MHC II (Abcam 1:100), besides the viewing of the damage pattern with cresyl violet. Slides are marked by different methods were evaluated qualitatively and quantitatively also some (Anti-Nogo A, anti-ED-1, anti-MHC-II and anti-tau-1), counts were carried out in the striatum and in the corpus callosum. The data were tabulated, statistically analyzed by Tukey test (p <0.05) and micrographs taken of the findings more representative. The slides were stained with cresyl violet revealed an increase in cell density by the infiltration of inflammatory cells to the ischemic area, with a significant increase on day 7. The blades immunostained for GFAP was found progressive increase of the population of astrocytes and an increase in cell volume 7 and 14 days. Oligodendrocyte pathology marked with Tau-1 had peak marking the 3rd day in the striatum and the 7th day in the corpus callosum, and loss of myelin compaction identified by MBP was better at 14, in the different treatment. The microglial activation identified by different immunoblots showed a peak on day 7, both in striatum and in the corpus callosum, but in the corpus callosum with a much smaller number compared to the striatum. The morphology of microglial underwent changes, which found the branched phenotype in control animals, as well as in early and late times after ischemia and amoeboid default / phagocytic day 7, coinciding with the largest number of activated cells. The count of Nogo-A + cells peaked at 3 days observed in the striatum, and there were no differences in the corpus callosum expression Nogo-A 3 to 14 days, only a decrease compared to 30 days. Thus, microinjections of ET-1 induced conspicuous striatal tissue loss, concomitant with progressive microglial activation, astrocytosis, loss of immunoreactivity for myelin basic protein and oligodendrocytes damage in various survival times after focal ischemia. These events affect a few SB tracts, as the corpus callosum. The establishment of the temporal evolution of these events is the neuropathological basis for future studies, in which they should handle the inflammatory response in order to minimize these tissue changes.
Acesso aberto (Open Access)
Avaliação comparativa da ultraestrutura e propriedades físicas do esmalte bovino, bubalino e humano
(2014-05) NOGUEIRA, Bárbara Catarina Lima; FERNANDES, Piero Maia; PAIVA, Augusto Cezar Justino; FAGUNDES, Nathália Carolina Fernandes; TEIXEIRA, Francisco Bruno; LIMA, Rafael Rodrigues
This study aimed to compare the morphology and physical properties of the enamel structure of bovine, buffalo and human teeth. Analysis of this tissue was performed by scanning electron microscopy, mineral composition, microhardness and surface roughness of enamel in 41 buffalo incisors (Bos taurus indicus), 41 bovine incisors (Pelorovis antiques), and 30 human permanent incisors. The results showed a significant similarity between the ultrastructure of enamel in these animal species and the one found in human samples. The chemical elements which presented higher concentration in bovine and buffalo enamel were: O,Ca and P, precisely those that form hydroxyapatite crystals - Ca10(PO4)6(OH)2. Knoop microhardness values showed no statistically significant differences between the three species. However, the surface roughness of buffalo enamel (2.16µm ±0.23) was significantly higher when compared with human (0.36µm ±0.05) and bovine teeth (0.41µm ±0.07). It is concluded that the characteristics and properties of bovine and buffalo enamel, as obtained from our analysis and testing, showed a similar morphology to that of humans. They showed a similar ultrastructural architecture, microhardness and mineral composition equivalent to the human dental tissue, becoming reference models for research.
Acesso aberto (Open Access)
Morfologia radicular da dentição permanente de Sapajus apella: morfometria, anatomia macroscópica, ultraestrutura e propriedades físicas
(2014-08) FERNANDES, Luanna de Melo Pereira; NASCIMENTO, Elder Monteiro do; NUNES, Camila Santa Rosa; VIEIRA, Elma Pinto; LINS, Paula Dias; TEIXEIRA, Francisco Bruno; COUTO, Roberta Souza D'Almeida; LIMA, Rafael Rodrigues
This paper aimed the anatomical study including morphometric, ultrastructural and physical properties of permanent teeth of Sapajus apella primate. Ten adult male monkeys were studied. The teeth were evaluated for their length, root anatomy (external and internal considering the number of roots and canals), direction and shape of the root canal, density and diameter of the tubular root canal, dentin microhardness, and composition. The root anatomy showed specificity regarding the number of roots of the second premolar and the presence of the third premolar. We observed a decrease in the number and diameter of dentinal tubules along the root canal, a statistically significant difference when compared with the apical and cervical regions. Similarities with human teeth were found in regard to microhardness values and proportion of chemical elements in the root dentin.