Publications by authors named "Alexandre Neves"

Introduction: Multiple force vector applications may be indicated when an arch segment or en masse intrusion is needed. This finite element method study aimed to evaluate the total deform the stress yielded in the bone and the miniplate when forces with different directions and magnitudes were applied.

Methods: First, the prototyped skull model was fabricated on the basis of computed tomography (CT) scans.

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The transcriptional mechanisms that allow neural stem cells (NSC) to balance self-renewal with differentiation are not well understood. Employing an RNAi screen we identify here NSC-TAFs, a subset of nine TATA-binding protein associated factors (TAFs), as NSC identity genes in We found that depletion of NSC-TAFs results in decreased NSC clone size, reduced proliferation, defective cell polarity and increased hypersensitivity to cell cycle perturbation, without affecting NSC survival. Integrated gene expression and genomic binding analyses revealed that NSC-TAFs function with both TBP and TRF2, and that NSC-TAF-TBP and NSC-TAF-TRF2 shared target genes encode different subsets of transcription factors and RNA-binding proteins with established or emerging roles in NSC identity and brain development.

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The Notch signaling pathway is involved in a wide variety of cell-fate decisions during development. The diverse behavior of Notch-activated cells is thought to depend on tissue- or cell-type-specific transcription factors, yet the identities of such factors and the mechanism of cooperation with the Notch pathway are largely unknown. We identify here an enhancer in the promoter of ref-1, a C.

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Much of the patterning of early C. elegans embryos involves a series of Notch interactions that occur in rapid succession and have distinct outcomes; however, none of the targets for these interactions have been identified. We show that the REF-1 family of bHLH transcription factors is a major target of Notch signaling in all these interactions and that most examples of Notch-mediated transcriptional repression can be attributed to REF-1 activities.

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RNA polymerase sigma factor sigma(F) initiates the prespore-specific program of gene expression during Bacillus subtilis sporulation. sigma(F) governs transcription of spoIIIG, encoding the late prespore-specific regulator sigma(G). However, transcription of spoIIIG is delayed relative to other genes under the control of sigma(F), and after synthesis, sigma(G) is initially kept in an inactive form.

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The four-cell C. elegans embryo contains two sister cells called ABa and ABp that initially have equivalent abilities to produce ectodermal cell types. Multiple Notch-mediated interactions occur during the early cell divisions that diversify the ABa and ABp descendants.

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