37 research outputs found

    Multi-aspect testing and ranking inference to quantify dimorphism in the cytoarchitecture of cerebellum of male, female and intersex individuals: a model applied to bovine brains

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    The dimorphism among male, female and freemartin intersex bovines, focusing on the vermal lobules VIII and IX, was analyzed using a novel data analytics approach to quantify morphometric differences in the cytoarchitecture of digitalized sections of the cerebellum. This methodology consists of multivariate and multi-aspect testing for cytoarchitecture-ranking, based on neuronal cell complexity among populations defined by factors, such as sex, age or pathology. In this context, we computed a set of shape descriptors of the neural cell morphology, categorized them into three domains named size, regularity and density, respectively. The output and results of our methodology are multivariate in nature, allowing an in-depth analysis of the cytoarchitectonic organization and morphology of cells. Interestingly, the Purkinje neurons and the underlying granule cells revealed the same morphological pattern: female possessed larger, denser and more irregular neurons than males. In the Freemartin, Purkinje neurons showed an intermediate setting between males and females, while the granule cells were the largest, most regular and dense. This methodology could be a powerful instrument to carry out morphometric analysis providing robust bases for objective tissue screening, especially in the field of neurodegenerative pathologies

    Multi-aspect testing and ranking inference to quantify dimorphism in the cytoarchitecture of cerebellum of male, female and intersex individuals: a model applied to bovine brains.

    Get PDF
    The dimorphism among male, female and freemartin intersex bovines, focusing on the vermal lobules VIII and IX, was analyzed using a novel data analytics approach to quantify morphometric differences in the cytoarchitecture of digitalized sections of the cerebellum. This methodology consists of multivariate and multi-aspect testing for cytoarchitecture-ranking, based on neuronal cell complexity among populations defined by factors, such as sex, age or pathology. In this context, we computed a set of shape descriptors of the neural cell morphology, categorized them into three domains named size, regularity and density, respectively. The output and results of our methodology are multivariate in nature, allowing an in-depth analysis of the cytoarchitectonic organization and morphology of cells. Interestingly, the Purkinje neurons and the underlying granule cells revealed the same morphological pattern: female possessed larger, denser and more irregular neurons than males. In the Freemartin, Purkinje neurons showed an intermediate setting between males and females, while the granule cells were the largest, most regular and dense. This methodology could be a powerful instrument to carry out morphometric analysis providing robust bases for objective tissue screening, especially in the field of neurodegenerative pathologies

    The motor cortex of the sheep: laminar organization, projections and diffusion tensor imaging of the intracranial pyramidal and extrapyramidal tracts

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    The laminar organization of the motor cortex of the sheep and other large domestic herbivores received scarce attention and is generally considered homologous to that of rodents and primates. Thickness of the cortex, subdivision into layers and organization are scarcely known. In the present study, we applied different modern morphological, mathematical and image-analyses techniques to the study of the motor area that controls movements of the forelimb in the sheep. The thickness of the cortex resulted comparable to that of other terrestrial Cetartiodactyls (but thicker than in marine Cetartiodactyls of similar body mass). The laminar organization showed marked development of layer 1, virtual absence of layer 4, and image analysis suggested prevalence of large irregular neural cells in the deeper layers. Diffusion tensor imaging revealed robust projections from the motor cortex to the pyramids in the brainstem, and well evident tracts descending to the tegmentum of the mesencephalon and dorsal pons. Our data contrast the general representation of the motor system of this species, considered to be predominantly based on extra-pyramidal tracts that originate from central pattern generators in the brainstem. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature

    Age-related changes in the primary auditory cortex of newborn, adults and aging bottlenose dolphins (Tursiops truncatus) are located in the upper cortical layers

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    Introduction: The auditory system of dolphins and whales allows them to dive in dark waters, hunt for prey well below the limit of solar light absorption, and to communicate with their conspecific. These complex behaviors require specific and sufficient functional circuitry in the neocortex, and vicarious learning capacities. Dolphins are also precocious animals that can hold their breath and swim within minutes after birth. However, diving and hunting behaviors are likely not innate and need to be learned. Our hypothesis is that the organization of the auditory cortex of dolphins grows and mature not only in the early phases of life, but also in adults and aging individuals. These changes may be subtle and involve sub-populations of cells specificall linked to some circuits. Methods: In the primary auditory cortex of 11 bottlenose dolphins belonging to three age groups (calves, adults, and old animals), neuronal cell shapes were analyzed separately and by cortical layer using custom computer vision and multivariate statistical analysis, to determine potential minute morphological differences across these age groups. Results: The results show definite changes in interneurons, characterized by round and ellipsoid shapes predominantly located in upper cortical layers. Notably, neonates interneurons exhibited a pattern of being closer together and smaller, developing into a more dispersed and diverse set of shapes in adulthood. Discussion: This trend persisted in older animals, suggesting a continuous development of connections throughout the life of these marine animals. Our findings further support the proposition that thalamic input reach upper layers in cetaceans, at least within a cortical area critical for their survival. Moreover, our results indicate the likelihood of changes in cell populations occurring in adult animals, prompting the need for characterization

    In utero androgen administration induces changes in gene expression and purkinje cell development in the cerebellum

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    Steroids play a major role in the development of the CNS with those brain areas involved in sexual behaviour having been the focus of most neuroendocrine studies to date e.g. the hypothalamus and pituitary gland (Feist and Schreck, 1996; Mong, et al., 1999; Toran-Allerand, et al., 1980). This occurs via intracellular and cell-surface receptors that regulate changes in protein synthesis (Mensah-Nyagan, et al., 1999) to modify events related to neuronal survival and synapse formation (Breedlove, 1992). Many steroidogenesis-associated enzymes have been described in the cerebellum and cortex, but the impact of steroids on their development has yet to be investigated. A steroidal fetal programming model was utilised to investigate how gene expression in these two brain regions is affected by steroid exposure during development, and examine how this may lead to a change in brain architecture and function. The main aims of this study were to identify changes in the cerebellar expression of genetic markers of steroid metabolism, using quantitative real-time polymerase chain reaction (qRT-PCR), that result from exposure to testosterone propionate (TP) during development in male sheep. The cerebellum follows a clear developmental trajectory and contains an established cytoarchitecture that enabled us to readily identify the effects of TP treatment on the developing brain by utilising histological analyses. Further alterations of gene expression in the developing male ovine cortex were also identified using microarray analysis. The results provide novel findings in regards to androgen-sensitive gene expression in the developing ovine cerebellum and cortex but perhaps the most striking result was that androgen over-exposure delays cerebellar development, which may have consequences in later life on motor and/or cognitive function

    An assay system to evaluate riboflavin/UV-A corneal phototherapy efficacy in a porcine corneal organ culture model

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    The purpose of this study is to investigate the response of a porcine corneal organ cultures to the riboflavin/UV-A phototherapy in the injury healing of induced lesions. A porcine corneal organ culture model has been established. Corneal alterations in the stroma were valuated setting an assay system, based on an automated image analysis method able to quantify the damaged (brightness values), within of the 24 regions of interest (ROIs) in which the corneal section has been divided and integrating the data analysis with a multi-aspect approach. Three group of corneas have been analyzed: (healthy, injured and injured-and-treated group). Our study revealed a significant effect of the riboflavin/UV-A phototherapy in the injury healing of porcine corneas after induced lesions. The injured corneas had significant differences of brightness values in comparison to treated (p< 0.00) and healthy (p<0.001) corneas whereas the treated and healthy corneas showed not significant difference (p = 0.995). Riboflavin/UV-A phototherapy shows a significant effect in the restoring the brightness values of damaged corneas to the values of healthy corneas, suggesting treatment restores the injury healing of corneas after lesions. Our assay system may be compared to clinical diagnostic method such as the OCT imaging for in vivo damaged ocular structures investigations

    An Assay System to Evaluate Riboflavin/UV-A Corneal Phototherapy Efficacy in a Porcine Corneal Organ Culture Model

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    The purpose of this study was to investigate the response of porcine corneal organ cultures to riboflavin/UV-A phototherapy in the injury healing of induced lesions. A porcine corneal organ culture model was established. Corneal alterations in the stroma were evaluated using an assay system, based on an automated image analysis method able to (i) localize the holes and gaps within the stroma and (ii) measure the brightness values in these patches. The analysis has been performed by dividing the corneal section in 24 regions of interest (ROIs) and integrating the data analysis with a "multi-aspect approach." Three group of corneas were analyzed: healthy, injured, and injured-and-treated. Our study revealed a significant effect of the riboflavin/UV-A phototherapy in the injury healing of porcine corneas after induced lesions. The injured corneas had significant differences of brightness values in comparison to treated (p < 0.00) and healthy (p < 0.001) corneas, whereas the treated and healthy corneas showed no significant difference (p = 0.995). Riboflavin/UV-A phototherapy shows a significant effect in restoring the brightness values of damaged corneas to the values of healthy corneas, suggesting treatment restores the injury healing of corneas after lesions. Our assay system may be compared to clinical diagnostic methods, such as optical coherence tomography (OCT) imaging, for in vivo damaged ocular structure investigations

    Physiological and morphological effects of short and long term lid-suture on cells in the lateral geniculate nucleus of cats

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    This study addresses three main issues which have clearly arisen from the literature and when answered, bear directly on the role of experience on neural development. In order to address these issues, 22 cats were reared with varying durations of lid suture and LGNd cell encounter rates and cell body sizes were collected. Control data were collected from normal subjects. Subjects reared with lid suture and from which data were collected before 17 months of age showed a reduction in the electrophysiological encounter rate for Y-cells and a reduction in average cell body size in geniculate laminae innervated by the deprived eye. Subjects from which data were collected at or after 17 months of age did not show a reduction in Y-cell encounter rate. In fact, it appears that X-cells were suppressed in the older subjects. Average cell body sizes in deprived geniculate laminae on the other hand, were smaller than normal. In these older subjects however, the relative difference between soma sizes in deprived and nondeprived laminae appears to decrease
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