Recent molecular insights on how the ectodermal layer is patterned in vertebrates are reviewed. Studies on the induction of the central nervous system (CNS) by Spemann's Organizer led to the isolation of noggin and chordin. These secretory proteins function by binding to, and inhibiting, ventral BMPs, in particular BMP-4. Neural induction can be considered as the dorsalization of ectoderm, in w...

Specific signaling molecules play a pivotal role in the induction and specification of tissues during early vertebrate embryogenesis. BMP-4 specifies ventral mesoderm differentiation and inhibits neural induction in Xenopus, whereas three molecules secreted from the organizer, noggin, follistatin and chordin dorsalize mesoderm and promote neural induction. Here we report that follistatin antago...

Insulin receptor (IR) and insulin-like growth factor-1 receptor (IGF1R) signalling is required for normal embryonic growth and development. Previous reports indicated that the IGF/IGF1R/MAPK pathway contributes to neural induction and the IGF/IGF1R/PI3K/Akt pathway to eye development. Here, we report the isolation of insulin3 encoding a novel insulin-like ligand involved in neural induction. In...

Background: Cell therapy is a potential therapeutic approach for neurodegenerative disorders. Human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) are an appropriate source of stem cells for use in various cell-based therapies. Objectives: In this study, we examined a real-time PCR approach for neural differentiation of hUCB-MSCs in vitro. Materials and Methods: MSCs were cultu...

The neural crest is a unique cell population induced at the lateral border of the neural plate. Neural crest is not produced at the anterior border of the neural plate, which is fated to become forebrain. Here, the roles of BMPs, FGFs, Wnts, and retinoic acid signaling in neural crest induction were analyzed by using an assay developed for investigating the posteriorization of the neural plate....

Neural networks with rectified linear unit activations are essentially multivariate linear splines. As such, one of many ways to measure the “complexity” or “expressivity” of a neural network is to count the number of knots in the spline model. We study the number of knots in fully-connected feedforward neural networks with rectified linear unit activation functions. We intentionally keep the n...

In chordates, formation of neural tissue from ectodermal cells requires an induction. The molecular nature of the inducer remains controversial in vertebrates. Here, using the early neural marker Otx as an entry point, we dissected the neural induction pathway in the simple embryos of Ciona intestinalis. We first isolated the regulatory element driving Otx expression in the prospective neural t...

Evidence is presented for a new pathway participating in anterior neural development. It was found that IGF binding protein 5 (IGFBP-5), as well as three IGFs expressed in early embryos, promoted anterior development by increasing the head region at the expense of the trunk in mRNA-injected Xenopus embryos. A secreted dominant-negative type I IGF receptor (DN-IGFR) had the opposite effect. IGF ...

Labaf, Maryam. M.S, Department of Mathematics and Statistics, Wright State University, 2017. Rule Extraction From Artificial Neural Networks Under Background Knowledge. It is well-known that the input-output behavior of a neural network can be recast in terms of a set of propositional rules, and under certain weak preconditions this is also always possible with positive (or definite) rules. Fur...

To use artiicial neural networks as part of a multistrategy learning system, there must be a way for neural networks to accept information, often expressed symbolically, from other systems. Moreover, neural networks must be able to transfer the results of their learning. A three-step process for learning using rule-based domain knowledge in combination with neural networks can address this task...