oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 27 )

2018 ( 45 )

2017 ( 53 )

2016 ( 57 )

Custom range...

Search Results: 1 - 10 of 24430 matches for " Cecilia Hedin-Pereira "
All listed articles are free for downloading (OA Articles)
Page 1 /24430
Display every page Item
Does cell lineage in the developing cerebral cortex contribute to its columnar organization?
Marcos R. Costa,Cecilia Hedin-Pereira
Frontiers in Neuroanatomy , 2010, DOI: 10.3389/fnana.2010.00026
Abstract: Since the pioneer work of Lorente de Nó, Ramón y Cajal, Brodmann, Mountcastle, Hubel and Wiesel and others, the cerebral cortex has been seen as a jigsaw of anatomic and functional modules involved in the processing of different sets of information. In fact, a columnar distribution of neurons displaying similar functional properties throughout the cerebral cortex has been observed by many researchers. Although it has been suggested that much of the anatomical substrate for such organization would be already specified at early developmental stages, before activity-dependent mechanisms could take place, it is still unclear whether gene expression in the ventricular zone (VZ) could play a role in the development of discrete functional units, such as minicolumns or columns. Cell lineage experiments using replication-incompetent retroviral vectors have shown that the progeny of a single neuroepithelial/radial glial cell in the dorsal telencephalon is organized into discrete radial clusters of sibling excitatory neurons, which have a higher propensity for developing chemical synapses with each other rather than with neighboring non-siblings. Here, we will discuss the possibility that the cell lineage of single neuroepithelial/radial glia cells could contribute for the columnar organization of the neocortex by generating radial columns of sibling, interconnected neurons. Borrowing some concepts from the studies on cell–cell recognition and transcription factor networks, we will also touch upon the potential molecular mechanisms involved in the establishment of sibling-neuron circuits.
Formation of cortical tissue from slices maintained in vitro: a model for radial and tangential migration studies
HEDIN-PEREIRA CECILIA,MORAES ELIZABETH C. P. DE,SANTIAGO MARCELO F.,MENDEZ-OTERO ROSALIA
Anais da Academia Brasileira de Ciências , 2000,
Abstract:
The 9-O-acetyl GD3 gangliosides are expressed by migrating chains of subventricular zone neurons in vitro
Miyakoshi, L.M.;Mendez-Otero, R.;Hedin-Pereira, C.;
Brazilian Journal of Medical and Biological Research , 2001, DOI: 10.1590/S0100-879X2001000500016
Abstract: neurons from the anterior subventricular zone (svz) of the cerebral cortex migrate tangentially to become interneurons in the olfactory bulb during development and in adult rodents. this migration was defined as neuronophilic, independent of a radial glial substrate. the cortical svz and the rostral migratory stream to the olfactory bulb were shown to be rich in 9-o-acetyl gd3 gangliosides (9-o-acgd3), which have been previously shown to be implicated in gliophilic migration in the rodent cerebral cortex and cerebellum. in the present study, we performed svz explant cultures using rats during their first postnatal week to analyze the expression of these gangliosides in chain migration of neuronal precursors. we characterized migrating chains of these neuroblasts through morphological analysis and immunocytochemistry for the neural cell adhesion molecule. by using the jones monoclonal antibody which binds specifically to 9-o-acgd3 we showed that migrating chains from the svz explants express 9-o-acgd3 which is distributed in a punctate manner in individual cells. 9-o-acgd3 is also present in migrating chains that form in the absence of radial glia, typical of the neuronophilic chain migration of the svz. our data indicate that 9-o-acetylated gangliosides may participate in neuronophilic as well as gliophilic migration.
The 9-O-acetyl GD3 gangliosides are expressed by migrating chains of subventricular zone neurons in vitro
Miyakoshi L.M.,Mendez-Otero R.,Hedin-Pereira C.
Brazilian Journal of Medical and Biological Research , 2001,
Abstract: Neurons from the anterior subventricular zone (SVZ) of the cerebral cortex migrate tangentially to become interneurons in the olfactory bulb during development and in adult rodents. This migration was defined as neuronophilic, independent of a radial glial substrate. The cortical SVZ and the rostral migratory stream to the olfactory bulb were shown to be rich in 9-O-acetyl GD3 gangliosides (9-O-acGD3), which have been previously shown to be implicated in gliophilic migration in the rodent cerebral cortex and cerebellum. In the present study, we performed SVZ explant cultures using rats during their first postnatal week to analyze the expression of these gangliosides in chain migration of neuronal precursors. We characterized migrating chains of these neuroblasts through morphological analysis and immunocytochemistry for the neural cell adhesion molecule. By using the Jones monoclonal antibody which binds specifically to 9-O-acGD3 we showed that migrating chains from the SVZ explants express 9-O-acGD3 which is distributed in a punctate manner in individual cells. 9-O-acGD3 is also present in migrating chains that form in the absence of radial glia, typical of the neuronophilic chain migration of the SVZ. Our data indicate that 9-O-acetylated gangliosides may participate in neuronophilic as well as gliophilic migration.
Cell migration in the postnatal subventricular zone
Menezes, J.R.L.;Marins, M.;Alves, J.A.J.;Fróes, M.M.;Hedin-Pereira, C.;
Brazilian Journal of Medical and Biological Research , 2002, DOI: 10.1590/S0100-879X2002001200002
Abstract: new neurons are constantly added to the olfactory bulb of rodents from birth to adulthood. this accretion is not only dependent on sustained neurogenesis, but also on the migration of neuroblasts and immature neurons from the cortical and striatal subventricular zone (svz) to the olfactory bulb. migration along this long tangential pathway, known as the rostral migratory stream (rms), is in many ways opposite to the classical radial migration of immature neurons: it is faster, spans a longer distance, does not require radial glial guidance, and is not limited to postmitotic neurons. in recent years many molecules have been found to be expressed specifically in this pathway and to directly affect this migration. soluble factors with inhibitory, attractive and inductive roles in migration have been described, as well as molecules mediating cell-to-cell and cell-substrate interactions. however, it is still unclear how the various molecules and cells interact to account for the special migratory behavior in the rms. here we will propose some candidate mechanisms for roles in initiating and stopping svz/rms migration.
John Locke och familjens makt ver uppfostran
Christer Hedin
Utbildning & Demokrati : Tidsskrift f?r Didaktik och Utbildningspolitik , 2007,
Abstract: JOHN LOCKE AND THE POWER OF THE FAMILY OVER EDUCATION. Who deserves author-ity over education? Plato was convinced that it was the state. Locke insisted onthe family. Mill, from his own hard-won experience, was convinced that theindividual should have more influence than the family. Of course, childrenhad to be compelled to learn basics; otherwise their freedom would be re-duced. John Locke lived in a time of growing capital formation. He defendedthe right of ownership as a fundamental human right. According to him, itfollowed from the right to life. Property was created through work, and workwas a way of using life. Parents had to have the decisive influence on educa-tion. They needed to be convinced that their heirs would manage their inher-itance in a responsible way. Locke is regarded as a father of democracy. How-ever, it can hardly be claimed that he was a promoter of democracy in educa-tion. His defence of private property led him to ascribe so much power overeducation to parents that individual rights were substantially curtailed.
AmadeusGrabauINMEMORIUM
SVEN,HEDIN
地质学报 , 1947,
Abstract: ItwaswithpainandgrievedemotionthatIreceivedthenewsofProfessorAmadeusGrabau'sdeceasesometimeago;andIfelt,deeplyandwarmly,thatIhadlostarealandfaithfulfriend,onewhohadbeenclosetomeinbrightandgloomyperiodsforverymanyyears.Aroundhisbierwereassembledinsorrow
El taller de escritura en posgrado: Representaciones sociales e interacción entre pares
Pereira,Cecilia; di Stefano,Mariana;
Revista signos , 2007, DOI: 10.4067/S0718-09342007000200007
Abstract: the present article shows a collection of experiences carried out in the context of a thesis writing workshop and proposes guidelines for a writing didactics at a postgraduate level. the experiences allow highlighting, in the frst place, the importance of theoretical conceptualization on different aspects of the writing practice that facilitate the construction of guiding criteria for production. in this respect, we highlight the incidence of the work done with the writer’s social representations regarding the appropriation of such criteria. in the second place, due to the recognition of the value of collaborative and presential work among pairs and experts at postgraduate level, the carried out experiences allow establishing some conditions for the occurrence of a critical and productive interchange, typical of exploratory conversation
El taller de escritura en posgrado: Representaciones sociales e interacción entre pares Writing workshops in postgraduate students: Social representations and peer interactions
Cecilia Pereira,Mariana di Stefano
Revista Signos , 2007,
Abstract: El presente artículo1 muestra experiencias desarrolladas en el contexto de un taller de escritura de tesis y propone pautas para una didáctica de la escritura en el nivel de posgrado2. Las experiencias permiten destacar, en primer lugar, la importancia de la conceptualización teórica de distintos aspectos de la práctica de la escritura que facilitan la construcción de criterios orientadores para la producción. Al respecto, se pone en relieve la incidencia del trabajo con las representaciones sociales del escritor para la apropiación de dichos criterios. En segundo lugar, a partir de reconocer el valor del trabajo colaborativo y presencial entre pares y con expertos en el nivel de posgrado, las experiencias desarrolladas permiten establecer algunas condiciones para que se produzca un intercambio crítico y productivo, propio de la conversación exploratoria The present article shows a collection of experiences carried out in the context of a thesis writing workshop and proposes guidelines for a writing didactics at a postgraduate level. The experiences allow highlighting, in the frst place, the importance of theoretical conceptualization on different aspects of the writing practice that facilitate the construction of guiding criteria for production. In this respect, we highlight the incidence of the work done with the writer’s social representations regarding the appropriation of such criteria. In the second place, due to the recognition of the value of collaborative and presential work among pairs and experts at postgraduate level, the carried out experiences allow establishing some conditions for the occurrence of a critical and productive interchange, typical of exploratory conversation
Calculus in physics classes at UFRGS: an exploratory study
Maria Cecilia Pereira Santarosa,Marco Antonio Moreira
Investiga??es em Ensino de Ciências , 2011,
Abstract: This study is part f a larger one whose general objective is to investigate and to develop a new strategy for teaching Differential and Integral Calculus I, specifically for physics majors, through a possible integration with the teaching of General and Experimental Physics I. With the specific objective of identifying physics problem-situations that may help in making sense of the mathematical concepts used in Calculus I, and languages and notations that might be used in the teaching of Calculus to favor physics learning, it was investigates, through an ethnographic study, the may mathematics is transposed to classes of General and Experimental Physics I, in classes of physics courses at the Federal University of Rio Grande do Sul (UFRGS). Some findings of this study confirmed those reported in the literature regarding the teaching and learning process in introductory college physics courses. These findings will subsidize the preparation of potentially meaningful instructional materials that will be used in a second stage of the research designed to investigate the learning of declarative and procedural knowledge in basic college physics under an approach that integrates problem-situation in physics and calculus mathematical concepts.
Page 1 /24430
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.