De novo assembly and annotation of a transcriptome during xylogenesis in Pinus canariensis Chr. Sm. ex DC

Nowadays, there is a great amount of genomic and transcriptomic data available about forest species, including ambitious projects looking for complete sequencing and annotation of different gymnosperm genomes [1, 2]. Pinus canariensis is an endemic conifer of the Canary Islands with re-sprouting capability and resilience against fire and mechanical damage, as result of an adaptation to volcanic environments. Additionally, this species has a high proportion of axial parenchyma compared with other conifers, and this tissue connects with radial parenchyma allowing transport of reserves. The most internal tracheids stop accumulating water [3], and get filled of resins and polyphenols synthesized by the axial parenchyma; this is the so-called ?torch-heartwood? [4], which avoids decay. This wood achieves very high prices due to its particular resistance to rot. These features make P. canariensis an interesting model species for the analysis of these developmental processes in conifers. In this study we aim to perform a complete transcriptome annotation during xylogenesis in Pinus canariensis, using next-generation sequencing (NGS) -Roche 454 pyrosequencing-, in order to provide a genomic resource for further analysis, including expression profiling and the identification of candidate genes for important adaptive features.

EDUCAÇÃO E HISTÓRIA A Escola Estadual Maria Iracema Munhoz, em São Bernardo do Campo, desde 1890 a 1930

Esta dissertação focaliza a trajetória do surgimento da Escola Estadual Maria Iracema Munhoz, apresentando o seu percurso desde 1890 até 1930. Para isso foi necessário fazer uma retrospectiva da educação brasileira, lembrar como surgiu São Bernardo, município onde está localizada a escola e, o surgimento da educação na cidade. O objetivo de reflexão e de pesquisa da presente dissertação foi buscar entender, pela história do passado, os problemas do presente, reconstruindo os avanços e os insucessos no processo da escolarização e das políticas públicas educacionais assumidas nesse período. A hipótese apresentada é que, nosso atraso educativo não vem tanto do que deixamos de fazer nas últimas décadas, mas do que fizemos nos séculos anteriores, em se tratando da educação.(AU)

EDUCAÇÃO E HISTÓRIA A Escola Estadual Maria Iracema Munhoz, em São Bernardo do Campo, desde 1890 a 1930

Esta dissertação focaliza a trajetória do surgimento da Escola Estadual Maria Iracema Munhoz, apresentando o seu percurso desde 1890 até 1930. Para isso foi necessário fazer uma retrospectiva da educação brasileira, lembrar como surgiu São Bernardo, município onde está localizada a escola e, o surgimento da educação na cidade. O objetivo de reflexão e de pesquisa da presente dissertação foi buscar entender, pela história do passado, os problemas do presente, reconstruindo os avanços e os insucessos no processo da escolarização e das políticas públicas educacionais assumidas nesse período. A hipótese apresentada é que, nosso atraso educativo não vem tanto do que deixamos de fazer nas últimas décadas, mas do que fizemos nos séculos anteriores, em se tratando da educação.(AU)

DESCONSTRUÇÃO DO PARADIGMA DO ENSINO DE ADMINISTRAÇÃO NO BRASIL UMA ANÁLISE METACRÍTICA DOS FATORES HISTÓRICO-ECONÔMICO-POLÍTICOS QUE INFLUENCIARAM E DETERMINARAM A IDEOLOGIA EDUCACIONAL BRASILEIRA NA ÁREA DE ADMINISTRAÇÃO.

O ensino de Administração no Brasil, assim como em outros países, teve início para atender à demanda por profissionais capacitados a responder a necessidade de organização das grandes empresas que estavam em processo de surgimento. Três grandes eixos sustentam o direcionamento desses cursos, ainda nos dias de hoje: econômico, político e educacional. A proposta do presente trabalho é a da reavaliação do paradigma que determinou a construção dos programas das Instituições de Ensino Superior da área de Administração, considerando-se que em tempos atuais, a estrutura sócio-econômica que demanda jovens e adultos formados por esses cursos, configura-se diferentemente daquela que motivou seu surgimento. Naquela época, tendo como inspiração as universidades norte-americanas, as IES brasileiras também visavam atender à demanda das grandes empresas aqui instaladas dentro do processo desenvolvimentista iniciado no governo Vargas. Atualmente, essas grandes empresas, tendo como foco a inovação tecnológica, não mas absorvem adequadamente os profissionais. Novas estruturas organizacionais como aquelas relacionadas com as Economias Solidárias, surgem como possibilidades para os estudantes.(AU)

DESCONSTRUÇÃO DO PARADIGMA DO ENSINO DE ADMINISTRAÇÃO NO BRASIL UMA ANÁLISE METACRÍTICA DOS FATORES HISTÓRICO-ECONÔMICO-POLÍTICOS QUE INFLUENCIARAM E DETERMINARAM A IDEOLOGIA EDUCACIONAL BRASILEIRA NA ÁREA DE ADMINISTRAÇÃO.

O ensino de Administração no Brasil, assim como em outros países, teve início para atender à demanda por profissionais capacitados a responder a necessidade de organização das grandes empresas que estavam em processo de surgimento. Três grandes eixos sustentam o direcionamento desses cursos, ainda nos dias de hoje: econômico, político e educacional. A proposta do presente trabalho é a da reavaliação do paradigma que determinou a construção dos programas das Instituições de Ensino Superior da área de Administração, considerando-se que em tempos atuais, a estrutura sócio-econômica que demanda jovens e adultos formados por esses cursos, configura-se diferentemente daquela que motivou seu surgimento. Naquela época, tendo como inspiração as universidades norte-americanas, as IES brasileiras também visavam atender à demanda das grandes empresas aqui instaladas dentro do processo desenvolvimentista iniciado no governo Vargas. Atualmente, essas grandes empresas, tendo como foco a inovação tecnológica, não mas absorvem adequadamente os profissionais. Novas estruturas organizacionais como aquelas relacionadas com as Economias Solidárias, surgem como possibilidades para os estudantes.(AU)

Inosine stimulates extensive axon collateral growth in the rat corticospinal tract after injury

The purine nucleoside inosine has been shown to induce axon outgrowth from primary neurons in culture through a direct intracellular mechanism. For this study, we investigated the effects of inosine in vivo by examining whether it would stimulate axon growth after a unilateral transection of the corticospinal tract. Inosine applied with a minipump to the rat sensorimotor cortex stimulated intact pyramidal cells to undergo extensive sprouting of their axons into the denervated spinal cord white matter and adjacent neuropil. Axon growth was visualized by anterograde tracing with biotinylated dextran amine and by immunohistochemistry with antibodies to GAP-43. Thus, inosine, a naturally occurring metabolite without known side effects, might help to restore essential circuitry after injury to the central nervous system.

The Fibrinogen Globe of Tenascin-C Promotes Basic Fibroblast Growth Factor-induced Endothelial Cell Elongation

To investigate the potential role of tenascin-C (TN-C) on endothelial sprouting we used bovine aortic endothelial cells (BAECs) as an in vitro model of angiogenesis. We found that TN-C is specifically expressed by sprouting and cord-forming BAECs but not by nonsprouting BAECs. To test whether TN-C alone or in combination with basic fibroblast growth factor (bFGF) can enhance endothelial sprouting or cord formation, we used BAECs that normally do not sprout and, fittingly, do not express TN-C. In the presence of bFGF, exogenous TN-C but not fibronectin induced an elongated phenotype in nonsprouting BAECs. This phenotype was due to altered actin cytoskeleton organization. The fibrinogen globe of the TN-C molecule was the active domain promoting the elongated phenotype in response to bFGF. Furthermore, we found that the fibrinogen globe was responsible for reduced cell adhesion of BAECs on TN-C substrates. We conclude that bFGF-stimulated endothelial cells can be switched to a sprouting phenotype by the decreased adhesive strength of TN-C, mediated by the fibrinogen globe.

Phosphatidylinositol 3-kinase signaling mediates angiogenesis and expression of vascular endothelial growth factor in endothelial cells

Phosphatidylinositol 3-kinase (PI 3-kinase) is a signaling molecule that controls numerous cellular properties and activities. The oncogene v-p3k is a homolog of the gene coding for the catalytic subunit of PI 3-kinase, p110α. P3k induces transformation of cells in culture, formation of hemangiosarcomas in young chickens, and myogenic differentiation in myoblasts. Here, we describe a role of PI 3-kinase in angiogenesis. Overexpression of the v-P3k protein or of cellular PI 3-kinase equipped with a myristylation signal, Myr-P3k, can induce angiogenesis in the chorioallantoic membrane (CAM) of the chicken embryo. This process is characterized by extensive sprouting of new blood vessels and enlargement of preexisting vessels. Overexpression of the myristylated form of the PI 3-kinase target Akt, Myr-Akt, also induces angiogenesis. Overexpression of the tumor suppressor PTEN or of dominant-negative constructs of PI 3-kinase inhibits angiogenesis in the yolk sac of chicken embryos, suggesting that PI 3-kinase and Akt signaling is required for normal embryonal angiogenesis. The levels of mRNA for vascular endothelial growth factor (VEGF) are elevated in cells expressing activated PI 3-kinase or Myr-Akt. VEGF mRNA levels are also increased by insulin treatment through the PI 3-kinase-dependent pathway. VEGF mRNA levels are decreased in cells treated with the PI 3-kinase inhibitor LY294002 and restored by overexpression of v-P3k or Myr-Akt. Overexpression of VEGF by the RCAS vector induces angiogenesis in chicken embryos. These results suggest that PI 3-kinase plays an important role in angiogenesis and regulates VEGF expression.

Nerve growth factor rapidly suppresses basal, NMDA-evoked, and AMPA-evoked nitric oxide synthase activity in rat hippocampus in vivo

In adult forebrain, nerve growth factor (NGF) influences neuronal maintenance and axon sprouting and is neuroprotective in several injury models through mechanisms that are incompletely understood. Most NGF signaling is thought to occur after internalization and retrograde transport of trkA receptor and be mediated through the nucleus. However, NGF expression in hippocampus is rapidly and sensitively regulated by synaptic activity, suggesting that NGF exerts local effects more dynamically than possible through signaling requiring retrograde transport to distant afferent neurons. Interactions have been reported between NGF and nitric oxide (NO). Because NO affects both neural plasticity and degeneration, and trk receptors can mediate signaling within minutes, we hypothesized that NGF might rapidly modulate NO production. Using in vivo microdialysis we measured conversion of l-[14C]arginine to l-[14C]citrulline as an accurate reflection of NO synthase (NOS) activity in adult rat hippocampus. NGF significantly reduced NOS activity to 61% of basal levels within 20 min of onset of delivery and maintained NOS activity at less than 50% of baseline throughout 3 hr of delivery. This effect did not occur with control protein (cytochrome c) and was not mediated by an effect of NGF on glutamate levels. In addition, simultaneous delivery of NGF prevented significant increases in NOS activity triggered by the glutamate receptor agonists N-methyl-d-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA). Rapid suppression by NGF of basal and glutamate-stimulated NOS activity may regulate neuromodulatory functions of NO or protect neurons from NO toxicity and suggests a novel mechanism for rapidly mediating functions of NGF and other neurotrophins.

Spontaneous corticospinal axonal plasticity and functional recovery after adult central nervous system injury

Although it is believed that little recovery occurs after adult mammalian spinal cord injury, in fact significant spontaneous functional improvement commonly occurs after spinal cord injury in humans. To investigate potential mechanisms underlying spontaneous recovery, lesions of defined components of the corticospinal motor pathway were made in adult rats in the rostral cervical spinal cord or caudal medulla. Following complete lesions of the dorsal corticospinal motor pathway, which contains more than 95% of all corticospinal axons, spontaneous sprouting from the ventral corticospinal tract occurred onto medial motoneuron pools in the cervical spinal cord; this sprouting was paralleled by functional recovery. Combined lesions of both dorsal and ventral corticospinal tract components eliminated sprouting and functional recovery. In addition, functional recovery was also abolished if dorsal corticospinal tract lesions were followed 5 weeks later by ventral corticospinal tract lesions. We found extensive spontaneous structural plasticity as a mechanism correlating with functional recovery in motor systems in the adult central nervous system. Experimental enhancement of spontaneous plasticity may be useful to promote further recovery after adult central nervous system injury.

Involvement of Ethylene in Potato Microtuber Dormancy

Potato (Solanum tuberosum L.) single-node explants undergoing in vitro tuberization produced detectable amounts of ethylene throughout tuber development, and the resulting microtubers were completely dormant (endodormant) for at least 12 to 15 weeks. The rate of ethylene production by tuberizing explants was highest during the initial 2 weeks of in vitro culture and declined thereafter. Continuous exposure of developing microtubers to the noncompetitive ethylene antagonist AgNO3 via the culture medium resulted in a dose-dependent increase in precocious sprouting. The effect of AgNO3 on the premature loss of microtuber endodormancy was observed after 3 weeks of culture. Similarly, continuous exposure of developing microtubers to the competitive ethylene antagonist 2,5-norbornadiene (NBD) at concentrations of 2 mL/L (gas phase) or greater also resulted in a dose-dependent increase in premature sprouting. Exogenous ethylene reversed this response and inhibited the precocious sprouting of NBD-treated microtubers. NBD treatment was effective only when it was begun within 7 d of the start of in vitro explant culture. These results indicate that endogenous ethylene is essential for the full expression of potato microtuber endodormancy, and that its involvement may be restricted to the initial period of endodormancy development.

Reconstitution of the hippocampal mossy fiber and associational-commissural pathways in a novel dissociated cell culture system.

Synapses of the hippocampal mossy fiber pathway exhibit several characteristic features, including a unique form of long-term potentiation that does not require activation of the N-methyl-D-aspartate receptor by glutamate, a complex postsynaptic architecture, and sprouting in response to seizures. However, these connections have proven difficult to study in hippocampal slices because of their relative paucity (<0.4%) compared to commissural-collateral synapses. To overcome this problem, we have developed a novel dissociated cell culture system in which we have enriched mossy fiber synapses by increasing the ratio of granule-to-pyramidal cells. As in vivo, mossy fiber connections are composed of large dynorphin A-positive varicosities contacting complex spines (but without a restricted localization). The elementary synaptic connections are glutamatergic, inhibited by dynorphin A, and exhibit N-methyl-D-aspartate-independent long-term potentiation. Thus, the simplicity and experimental accessibility of this enriched in vitro mossy fiber pathway provides a new perspective for studying nonassociative plasticity in the mammalian central nervous system.

Spatial integration and cortical dynamics.

Cells in adult primary visual cortex are capable of integrating information over much larger portions of the visual field than was originally thought. Moreover, their receptive field properties can be altered by the context within which local features are presented and by changes in visual experience. The substrate for both spatial integration and cortical plasticity is likely to be found in a plexus of long-range horizontal connections, formed by cortical pyramidal cells, which link cells within each cortical area over distances of 6-8 mm. The relationship between horizontal connections and cortical functional architecture suggests a role in visual segmentation and spatial integration. The distribution of lateral interactions within striate cortex was visualized with optical recording, and their functional consequences were explored by using comparable stimuli in human psychophysical experiments and in recordings from alert monkeys. They may represent the substrate for perceptual phenomena such as illusory contours, surface fill-in, and contour saliency. The dynamic nature of receptive field properties and cortical architecture has been seen over time scales ranging from seconds to months. One can induce a remapping of the topography of visual cortex by making focal binocular retinal lesions. Shorter-term plasticity of cortical receptive fields was observed following brief periods of visual stimulation. The mechanisms involved entailed, for the short-term changes, altering the effectiveness of existing cortical connections, and for the long-term changes, sprouting of axon collaterals and synaptogenesis. The mutability of cortical function implies a continual process of calibration and normalization of the perception of visual attributes that is dependent on sensory experience throughout adulthood and might further represent the mechanism of perceptual learning.

Expression cloning of a human polysialyltransferase that forms the polysialylated neural cell adhesion molecule present in embryonic brain.

Polysialic acid is a developmentally regulated posttranslational modification of the neural cell adhesion molecule (N-CAM). It has been suggested that this large anionic carbohydrate modulates the adhesive property of N-CAM, but the precise function of polysialic acid is not known. Here we describe the isolation and functional expression of a cDNA encoding a human polysialyltransferase. For this expression cloning, COS-1 cells were cotransfected with a human fetal brain cDNA library and a cDNA encoding human N-CAM. Transfected COS-1 cells were stained with a monoclonal antibody specific for polysialic acid and enriched by fluorescence-activated cell sorting. Sibling selection of recovered plasmids resulted in a cDNA clone that directs the expression of polysialic acid on the cell surface. The deduced amino acid sequence indicates that the polysialyltransferase shares a common sequence motif with other sialyltransferases cloned so far. The polysialyltransferase is, however, distinct by having two clusters of basic amino acids. The amount of the polysialyltransferase transcripts correlates well with the formation of polysialic acid in various human tissues, and is abundant in the fetal brain but not in the adult brain. Moreover, HeLa cells stably expressing polysialic acid and N-CAM promoted neurite outgrowth and sprouting. These results indicate that the cloned polysialyltransferase forms polysialylated, embryonic N-CAM, which is critical for plasticity of neural cells.

Ganglioside GM1 binds to the Trk protein and regulates receptor function.

Several lines of evidence have suggested that ganglioside GM1 stimulates neuronal sprouting and enhances the action of nerve growth factor (NGF), but its precise mechanism is yet to be elucidated. We report here that GM1 directly and tightly associates with Trk, the high-affinity tyrosine kinase-type receptor for NGF, and strongly enhances neurite outgrowth and neurofilament expression in rat PC12 cells elicited by a low dose of NGF that alone is insufficient to induce neuronal differentiation. The potentiation of NGF activity by GM1 appears to involve tyrosine-autophosphorylation of Trk, which contains intrinsic tyrosine kinase activity that has been localized to the cytoplasmic domain. In the presence of GM1 in culture medium, there is a > 3-fold increase in NGF-induced autophosphorylation of Trk as compared with NGF alone. We also found that GM1 could directly enhance NGF-activated autophosphorylation of immunoprecipitated Trk in vitro. Monosialoganglioside GM1, but not polysialogangliosides, is tightly associated with immunoprecipitated Trk. Furthermore, such tight association of GM1 with Trk appears to be specific, since a similar association was not observed with other growth factor receptors, such as low-affinity NGF receptor (p75NGR) and epidermal growth factor receptor (EGFR). Thus, these results strongly suggest that GM1 functions as a specific endogenous activator of NGF receptor function, and these enhanced effects appear to be due, at least in part, to tight association of GM1 with Trk.