Dual function of Slit2 in repulsion and enhanced migration of trunk, but not vagal, neural crest cells

Neural crest precursors to the autonomic nervous system form different derivatives depending upon their axial level of origin; for example, vagal, but not trunk, neural crest cells form the enteric ganglia of the gut. Here, we show that Slit2 is expressed at the entrance of the gut, which is selectively invaded by vagal, but not trunk, neural crest. Accordingly, only trunk neural crest cells express Robo receptors. In vivo and in vitro experiments demonstrate that trunk, not vagal, crest cells avoid cells or cell membranes expressing Slit2, thereby contributing to the differential ability of neural crest populations to invade and innervate the gut. Conversely, exposure to soluble Slit2 significantly increases the distance traversed by trunk neural crest cells. These results suggest that Slit2 can act bifunctionally, both repulsing and stimulating the motility of trunk neural crest cells

New methods for chicken embryo manipulations

The capacity to image a growing embryo while simultaneously studying the developmental function of specific molecules provides invaluable information on embryogenesis. However, until recently, this approach was accomplished with difficulty both because of the advanced technology needed and because an easy method of minimizing damage to the embryo was unavailable. Here, we present a novel way of adapting the well-known EC culture of whole chick embryos to time-lapse imaging and to functional molecular studies using blocking agents. The novelty of our method stems from the ability to apply blocking agents ex ovo as well as in ovo. We were able to study the function of a set of molecules by culturing developing embryos ex ovo in tissue culture media containing these molecules or by injecting them underneath the live embryo in ovo. The in ovo preparation is particularly valuable, because it extends the period of time during which the developmental function of the molecule can be studied and it provides an easy, reproducible method for screening a batch of molecules. These new techniques will prove very helpful in visualizing and understanding the role of specific molecules during embryonic morphogenesis, including blood vessel formation

Emergence and migration of trunk neural crest cells in a snake, the California Kingsnake (Lampropeltis getula californiae)

<p>Abstract</p> <p>Background</p> <p>The neural crest is a group of multipotent cells that emerges after an epithelial-to-mesenchymal transition from the dorsal neural tube early during development. These cells then migrate throughout the embryo, giving rise to a wide variety derivatives including the peripheral nervous system, craniofacial skeleton, pigment cells, and endocrine organs. While much is known about neural crest cells in mammals, birds, amphibians and fish, relatively little is known about their development in non-avian reptiles like snakes and lizards.</p> <p>Results</p> <p>In this study, we show for the first time ever trunk neural crest migration in a snake by labeling it with DiI and immunofluorescence. As in birds and mammals, we find that early migrating trunk neural crest cells use both a ventromedial pathway and an inter-somitic pathway in the snake. However, unlike birds and mammals, we also observed large numbers of late migrating neural crest cells utilizing the inter-somitic pathway in snake.</p> <p>Conclusions</p> <p>We found that while trunk neural crest migration in snakes is very similar to that of other amniotes, the inter-somitic pathway is used more extensively by late-migrating trunk neural crest cells in snake.</p

Lunatic fringe causes expansion and increased neurogenesis of trunk neural tube and neural crest populations

Both neurons and glia of the PNS are derived from the neural crest. In this study, we have examined the potential function of lunatic fringe in neural tube and trunk neural crest development by gain-of-function analysis during early stages of nervous system formation. Normally lunatic fringe is expressed in three broad bands within the neural tube, and is most prominent in the dorsal neural tube containing neural crest precursors. Using retrovirally-mediated gene transfer, we find that excess lunatic fringe in the neural tube increases the numbers of neural crest cells in the migratory stream via an apparent increase in cell proliferation. In addition, lunatic fringe augments the numbers of neurons and upregulates Delta-1 expression. The results indicate that, by modulating Notch/Delta signaling, lunatic fringe not only increases cell division of neural crest precursors, but also increases the numbers of neurons in the trunk neural crest

Relações Coparentais e Auto-Eficácia de Cuidadores de Crianças com Paralisia Cerebral

La baja coparentalidad y la autoeficacia parental tienen un impacto negativo en el desarrollo de los niños. El objetivo de este estudio fue describir y analizar la autoeficacia parental y la autoeficacia de 84 cuidadores de niños con parálisis cerebral (PC) en Brasil. Se utilizó: el Inventario Sociodemográfico (ISD), el Sistema de Clasificación de la Función Motora Gruesa (GMFCS), Escala de Autoeficacia, Coparenting Questionnaire(CQ). Se sometieron los datos a las estadísticas descriptivas y análisis de correspondencia. Los resultados del ISD mostraron que las madres son las principales cuidadoras de los niños con PC, que son principalmente niñas, y se evalúan en el nivel V en la escala GMFCS. Bajos niveles de coparentalidad y autoeficacia en los cuidadores jóvenes que cuidan a niñas mayores de seis años. La autoeficacia fue mayor para la atención básica y diaria, como alimentar e higienizar, y menor para aquellos que involucran convulsiones y aspectos subjetivos. No se encontraron correlaciones significativas entre coparentalidad y autoeficacia. Se concluye que las intervenciones deben planificarse para aumentar la coparentalidad y la autoeficacia parental.Low parental coparenting and self-efficacy negatively impact children’s development. Our study sought to describe and analyze the parental coparenting and self-efficacy of 84 caregivers of children with cerebral palsy (CP) in Brazil. We used a Sociodemographic Inventory (SDI), Gross Motor Function Classification System (GMFCS), Self-efficacy Scale and Coparenting Questionnaire (CQ). Data were subjected to descriptive statistics and Correspondence Analysis. ISD results showed the mothers as the main caregivers of children with CP, being mostly girls at level V in the GMFCS scale. Low levels of coparenting and self-efficacy were observed in young caregivers, caring for girls older than six years old. Self-efficacy was higher regarding basic and daily care such as feeding and performing personal hygiene, and lower regarding seizures and subjective aspects. No significant correlations were found between coparenting and self-efficacy. We concluded that interventions should be planned to increase parental coparenting and parental self-efficacy.A baixa coparentalidade e autoeficácia parental impactam negativamente no desenvolvimento dos filhos. O objetivo deste estudo foi descrever e analisar a coparentalidade e autoeficácia parental de 84 cuidadores de crianças com paralisia cerebral (PC) no Brasil. Utilizou-se: Inventário Sociodemográfico (ISD), Sistema de Classificação da Função Motora Grossa (GMFCS), Escala de Auto-eficácia, Coparenting Questionnaire (CQ). Os dados foram submetidos à estatística descritiva e à Análise de Correspondência. Os resultados do ISD mostraram que as mães são as cuidadoras principais das crianças com PC, sendo estas prioritariamente meninas, e avaliada no nível V na Escala GMFCS. Níveis baixos de coparentalidade e autoeficácia em cuidadores jovens, cuidando de meninas maiores de seis anos. A auto-eficácia foi mais elevada para cuidados básicos e diários, como alimentar e higienizar, e menores para os que envolveram convulsões, e aspectos subjetivos. Não foram encontradas correlações significativas entre coparentalidade e autoeficácia. Conclui-se que intervenções devem ser planejadas visando aumentar a coparentalidade e auto-eficácia parental

Evaluation of the effect of Sidoarjo mud on aquatic life using chromatophores and the microstructure of fish scales

The Sidoarjo mud is the first visible phenomenon of a mud volcano that occurs in a human settlement and which is subsequently channelled into a river. Clay, aluminium and iron were reported to be the dominant contaminants that could possibly come into contact with and accumulate on the surface of local fish and initiate alteration in scale microstructure. The aim of this study was to evaluate the extent of water body contamination in the Sidoarjo mud by evaluating the chromatophore density and microstructure deformation of fish scales that act as biomarkers. Scale samples were obtained from caged Mozambique tilapia (Oreochromis mossambicus) fish that were placed downstream and upstream of the Sidoarjo mud spillway pipes. With respect to melanophore density, it was found that the scales of fish exposed in the downstream section were significantly lower in chromatophores (100 chr/mm²). This study suggested that the density of chromatophores was closely related to the concentration of total suspended solids (r = 0.69), which was possibly enhanced by iron (r = 0.56). Using scanning electron microscopy analysis, some deformation, i.e. irregularity of spherule shape and increasing pits in the space between ridges, were observed

Effect of NRG1, GDNF, EGF and NGF in the Migration of a Schwann Cell Precursor Line

The Schwann cells are the myelinating glia of the peripheral nervous system that originated during development from the highly motile neural crest. However, we do not know what the guidance signals for the Schwann cell precursors are. Therefore, we set to test some of the known neurotrophins that are expressed early in developing embryos and have been shown to be critical for the survival and patterning of developing glia and neurons. The goal of this study was to determine more specifically if GDNF, NRG1 and NGF are chemoattractants and/or chemokinetic molecules for a Schwann cell precursor line, the Spl201. We performed live chemoattraction assays, with imaging and also presented these molecules as part of their growing substrate. Our results show for the first time that GDNF and NRG1 are potent chemoattractive and chemokinetic molecules for these cells while NGF is a chemokinetic molecule stimulating their motility

ESCOLARIZAÇÃO DE UMA CRIANÇA COM SÍNDROME DE DOWN: UM ESTUDO SOBRE ESTRESSE PARENTAL SOB A PERSPECTIVA MATERNA

A família, frente a um diagnóstico de Síndrome de Down (SD), pode traçar um destino para a criança determinado pela baixa crença no potencial cognitivo e social desta, acarretando possíveis fracassos no processo de socialização e escola­rização. A figura materna desempenha um papel importante no desenvolvimento da criança, servindo de elo intermediário entre ela e o meio, ajudando-a em sua adaptação. Considerando tal afirmação, este estudo objetivou compreender como a percepção materna pode interferir no processo de escolarização de uma criança com SD levando em consideração a ocorrência de estresse parental. Trata-se de um estudo de caso descritivo de abordagem qualitativa realizado com uma mãe de uma menina com SD em idade escolar, na cidade de Altamira-Pará-Brasil. Foi realizada uma entrevista, no local de trabalho da mãe, utilizando-se um roteiro composto por dez questões." Os resultados evidenciaram que a mãe apresentou percepção positiva diante do contexto do nascimento de uma filha com SD, assim como diante do processo de iniciação escolar da mesma, fundamentalmente por demonstrar baixas características pertinentes ao estresse parental, típico na maioria das famílias de crianças com deficiência, o que favoreceu e facilitou o processo de escolarização da filha. Conclui-se que a percepção materna pode influenciar positiva ou negativamente o processo de escolarização

Vivências da maternidade durante a graduação: uma revisão sistemática

ResumoO objetivo desta pesquisa foi compreender os desafios e que tipo de apoio social estudantes universitárias têm no seu dia a dia para conseguir concluir a graduação, tendo que conciliar a maternidade e a vida universitária. Trata-se de uma revisão sistemática, sendo o corpus artigos científicos identificados no Banco de Dados da Capes, utilizando-se os descritores gravidez AND estudante universitária; mães AND universitárias, sendo selecionados cinco artigos publicados entre os anos de 2009 a 2018. O auxílio da família, juntamente com a existência de creches universitárias, são alternativas de apoio emocional e estrutural para que as mães-acadêmicas consigam concluir a graduação. Conclui-se que as mulheres que se tornam mães durante a graduação estão mais propensas à desistência do curso.Palavras-chave: Mães-universitárias. Apoio social. Evasão. Maternity leads during graduation: a systematic review AbstractThe objective of this research was to understand the challenges and what kind of social support university students have in their daily life to achieve graduation, having to reconcile motherhood and university life. It is a systematic review, being the corpus scientific articles identified in the Capes Database, using the descriptors pregnancy AND university student; mothers AND university students, five articles published between the years 2009 and 2018 were selected. Family support, together with the existence of university day care centers, are alternatives for emotional and structural support for the academic mothers to complete graduation. It is concluded that women who become mothers during graduation are more likely to drop out of school.Keywords: University mothers. Social support. Evasion.

Characterization of the trunk neural crest in the bamboo shark, Chiloscyllium punctatum

The neural crest is a population of mesenchymal cells that after migrating from the neural tube gives rise to structure and cell types: the jaw, part of the peripheral ganglia, and melanocytes. Although much is known about neural crest development in jawed vertebrates, a clear picture of trunk neural crest development for elasmobranchs is yet to be developed. Here we present a detailed study of trunk neural crest development in the bamboo shark, Chiloscyllium punctatum. Vital labeling with dioctadecyl tetramethylindocarbocyanine perchlorate (DiI) and in situ hybridization using cloned Sox8 and Sox9 probes demonstrated that trunk neural crest cells follow a pattern similar to the migratory paths already described in zebrafish and amphibians. We found shark trunk neural crest along the rostral side of the somites, the ventromedial pathway, the branchial arches, the gut, the sensory ganglia, and the nerves. Interestingly, C. punctatum Sox8 and Sox9 sequences aligned with vertebrate SoxE genes, but appeared to be more ancient than the corresponding vertebrate paralogs. The expression of these two SoxE genes in trunk neural crest cells, especially Sox9, matched the Sox10 migratory patterns observed in teleosts. Also of interest, we observed DiI cells and Sox9 labeling along the lateral line, suggesting that in C. punctatum, glial cells in the lateral line are likely of neural crest origin. Although this has been observed in other vertebrates, we are the first to show that the pattern is present in cartilaginous fishes. These findings demonstrate that trunk neural crest cell development in C. punctatum follows the same highly conserved migratory pattern observed in jawed vertebrates