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Unveiling Hidden Neural Codes: SIMPL – A Scalable and Fast Approach for Optimizing Latent Variables and Tuning Curves in Neural Population Data

Dr. Rishabh Pathak
This research paper presents SIMPL (Scalable Iterative Maximization of Population-coded Latents), a novel, computationally efficient algorithm designed to refine the estimation of latent variables and tuning curves from neural population activity. Latent variables in neural data represent essential low-dimensional quantities encoding behavioral or cognitive states, which neuroscientists seek to identify to understand brain computations better. Background and Motivation Traditional approaches commonly assume the observed behavioral variable as the latent neural code. However, this assumption can lead to inaccuracies because neural activity sometimes encodes internal cognitive states differing subtly from observable behavior (e.g., anticipation, mental simulation). Existing latent variable models face challenges such as high computational cost, poor scalability to large datasets, limited expressiveness of tuning models, or difficulties interpreting complex neural network-based functio...
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The expression of Notch-related genes in the differentiation of BMSCs into dopaminergic neuron-like cells.

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Dr. Rishabh Pathak


 

The expression of Notch-related genes plays a crucial role in the differentiation of human bone marrow mesenchymal stem cells (h-BMSCs) into dopaminergic neuron-like cells. The Notch signaling pathway is involved in regulating cell fate decisions, including the differentiation of BMSCs. In the study discussed in the PDF file, changes in the expression of Notch-related genes were observed during the differentiation process.

Specifically, the study utilized a human Notch signaling pathway PCR array to detect the expression levels of 84 genes related to the Notch signaling pathway, including ligands, receptors, target genes, cell proliferation and differentiation-related genes, and neurogenesis-related genes. The array also included genes from other signaling pathways that intersect with the Notch pathway, such as Sonic hedgehog and Wnt receptor signaling pathway members.

During the differentiation of h-BMSCs into dopaminergic neuron-like cells, the expression levels of Notch-related genes were found to be altered compared to the control group. For example, the expression of Notch ligands like Jagged1 and Jagged2, as well as key proteins like Presenilin2 (PSEN2) and ADAM metallopeptidase domain 10 (ADAM10) involved in Notch receptor cleavage, showed significant changes during the induction process.

Furthermore, the study observed downregulation of HES1, a target gene of Notch signaling, indicating suppression of the Notch pathway during differentiation. These findings suggest that the Notch signaling pathway is dynamically regulated during the differentiation of BMSCs into dopaminergic neuron-like cells, highlighting the importance of Notch-related genes in this process.

In conclusion, the expression of Notch-related genes is a key aspect of the molecular mechanisms involved in the differentiation of BMSCs into dopaminergic neuron-like cells, providing insights into the role of the Notch signaling pathway in this cellular differentiation process.

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