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BACKGROUND: Recently, some studies about primates have claimed the importance of the vessels to maintain the muscles working; in fact, the arterial supply could suggest how strenuous the muscular performance is associated to locomotor behavior. The aim of this work was to study the anatomy of the arteries of the forelimbs of different groups of primates to evidence a general arterial model in comparative terms. METHODS: We propose a biophysical explanation for the arterial pattern of the forelimbs of primates' groups. RESULTS: Three pattern of the forelimb arteries in Primates were descript and the differences were explained using mathematical formulas. CONCLUSIONS: The anatomical study about the comparative anatomy of the arteries of the forelimbs of primates provided hypothesis about the three observed models, mainly in relation to brachial artery division and the number of the palmar arches, in mathematical models' terms.

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The outer cortical table of the parietal bone has been commonly used as a calvarial bone graft site for the craniofacial reconstruction. However, little is known about how removing the outer table may affect the function and structure of the inner table, and how the knowledge of the biomechanics and material properties of cortical bones will help the calvarial graft to better integrate into the biological and mechanical functions of its surrounding native tissues. In this study, it was hypothesized that there were significant differences in both density and material properties between inner and outer cortical plates in cranial bones. Twelve cylindrical specimens, including inner-outer layers, of cortical parietal bone of a female baboon were collected. Cortical thicknesses and densities were measured, and elastic properties were assessed using an ultrasonic technique. Results demonstrated remarkable difference in both thickness (t = 8.248, p ≤0.05) and density (t = 4.926, p≤0.05) between inner and outer cortical paired samples. Orthotropic characteristics of the cortical plates were detected as well, these findings suggest that there are differences in biomechanical properties between two surfaces of cranial bones at both tissue and organ levels. How these differences are linked to the stress environments of the inner and outer cranial cortical layers awaits further studies. Further study will greatly enhance our ability to address questions derived from both morphological and craniofacial medicine fields about the development and biomechanics of craniofacial skeletons.

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The anatomical comparative studies among the primates are important for the investigation of ethology, evolution, taxonomy, and comprehension of tools by hominoids. Especially the anatomical knowledge of Cebus contributes to conservation of the species, and to development of surgical procedures and clinical treatments of these animals, as they frequently are victims of automobile accidents. Recent anatomical studies came to a wrong conclusion regarding behavioral traits of Cebus, ascribed to few data available in previous literature. Therefore, to provide anatomical data and to support the other sciences related to anatomy, and to develop surgical and/or clinical procedures, we described the nerves of the legs of Cebus foccusing on their position and trajectory, as wll as innerved muscles, and compared these results with those of humans and other primates. Eight adult capuchin specimens were used for this study. The anatomical comparative study of the leg's nerves of Cebus demonstrated that, in general, structural organization of the nerves is similar among the four primates analyzed here (Cebus, chimpanzees, baboons and humans), which might be attributed to the fact that the all four primates have similar body structures. However, nerve trajectory and muscles innervation in Cebus was more similar to baboons.(AU)

Os estudos anatômicos comparativos entre os primatas são importantes para pesquisas associadas com a etologia, evolução, taxonomia e compreensão dos usos de ferramentas pelos hominídeos. Especificamente, o conhecimento anatômico sobre Cebus contribui para sua própria conservação e para o desenvolvimento de procedimentos cirúrgicos e tratamentos clínicos destes animais, pois são frequentemente vítimas de acidentes automobilísticos. Recentemente, estudos sobre características comportamentais de Cebus indicaram conclusões erradas sobre sua anatomia, o que pode ser atribuído aos poucos dados disponíveis sobre a anatomia desses animais na literatura especializada. Portanto, para fornecer dados anatômicos e fornecer suporte para as outras ciências relacionadas com a anatomia e também desenvolver procedimentos cirúrgicos e/ou clínicos, foram descritos os nervos das pernas de Cebus com enfoque sobre a posição, a trajetória e os músculos inervados, e comparar esses resultados com os dos humanos modernos e outros primatas. Oito espécimes adultos de macacos-prego foram usados para este estudo. O estudo anatômico comparativo dos nervos da perna de Cebus demonstrou que, em geral, a organização estrutural dos nervos é semelhante entre os quatro primatas aqui analisados (Cebus, chimpanzés, babuínos e humanos modernos), o que pode ser atribuído ao fato de que os quatro primatas terem estruturas corporais semelhantes. No entanto, a trajetória dos nervos e a inervação dos músculos em Cebus o aproximam dos babuínos.(AU)

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Previous observations have shown that astrocytes with interlaminar processes are present in the cerebral cortex of humans and New and Old World monkeys, but not in the rodent. The present report furthers the analysis of possible evolutionary aspects regarding the expression of such astroglial features. A comparison between young and adult Microcebus murinus, a prosimian, and Old World monkeys (Macaca mulatta and Papio hamadryas) is presented. Brain samples were processed for glial fibrillary acidic protein (GFAP), vimentin, MAP2 and SMI 311 immunocytochemistry, using different procedures. The cerebral cortex of adult Microcebus showed the presence of long astroglial processes, albeit reduced in number and length with respect to those observed in Old World monkeys. Macaca and Papio showed dense packing of such processes extending in most cortical regions to a depth of approximately 700 micrometers. Based on double immunolabelling for GFAP and MAP 2 antigens, the location and extent of these processes was shown to overlap with areas traversed by bundles and individual apical dendrites. Aged Old World specimens depicted an increased thickness of terminal portions of interlaminar processes, with increased morphological alterations. Comparisons made between the average thickness of the "brush" composed of interlaminar processes and the thickness of lamina I among the species analyzed disclosed an absence of relationship between them. This suggests that interlaminar processes do not represent cellular adaptations to the increase in thickness in superficial cortical laminae, but rather to some other evolutionary pressure. Since astroglial interlaminar processes are already present in a prosimian, although in a comparatively reduced manner, it is suggested that such processes underwent an early expression within the primate order, with increasing presence in more recent primate species.

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We used light microscopy to compare the stereology of the myocytes from the following regions of the baboon's heart: a) cardiac walls (crista terminalis, interatrial and interventricular septa) and b) cardiac conduction tissue (atrioventricular bundle). Six hearts were perfused and several pieces of tissue were taken from these regions. A staggered test lattice consisting of cycloids was superimposed on twelve random pairs of photomicrographs in order to make disectors, and on twelve other random fields for each cardiac region in order to estimate certain stereological parameters. Statistically significant differences were found when comparing the number of myocytes from the crista terminalis (highest value) with either the interatrial or interventricular septum. There is also a significant difference between the number of myocytes in the interventricular septum and the atrioventricular bundle (highest value). For the mean profile area of the myocytes, significant differences were found between the myocytes of both the crista terminalis and the interatrial septum, and those of the interventricular septum (highest value). Under the light microscope, myocytes from the two regions of the atrial wall studied were indistinguishable in size, since they constitute a single cell population. It was also impossible to distinguish them from the atrioventricular cells. The myocytes from the interventricular septum differed in both size and number from those of the right atrium, but only in number from those of the atrioventricular bundle.

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The present work studies the atrioventricular (AV) junctional area in 15 hearts of P. cynocephalus perfused with phosphate-buffered formal 10%; 12 hearts were studied by gross anatomy and mesoscopic dissection, 3 hearts were serial sectioned in frontal plane (10 micron) and stained by trichromic method. The results show that the junctional AV area in P. cynocephalus is approximately similar to the same region in M. fascicularis and also in the human heart (Mandarim-de-Lacerda et Penteado in press, Mandarim-de-Lacerda et Hureau in press). It was impossible to dissect the AV node and AV bundle while the left bundle branch was easily identified as a calibrous fan-like fashion on the left side of the interventricular septum. The right bundle branch left the AV bundle and penetrated the myocardium of the trabecula septo-marginalis (moderator band).

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