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Tabaee Damavandi, P.

Publications and source records attributed to Tabaee Damavandi, P..

2 recordsLinked to original sources

A Brain Circuit for Status Epilepticus

Status epilepticus (SE) is a life-threatening persistent epileptic seizure that can arise from various brain structures, leaving its brain circuit unknown. In this study, we utilize brain imaging changes during SE to reveal the brain architecture and circuit of persistent seizures. Multimodal lesion mapping identified that brain imaging changes during SE localize to a specific predisposed brain architecture characterized by increased metabolic rate, high synaptic and mitochondrial density, glutamate (mGLUR5 and NMDA) and GABA receptors. Gene expression patterns within lesion locations revealed a transcriptomic profile enriched for epilepsy pathologies (including SE), neuronal and synaptic processes, and glutamate signaling. Lesion network mapping demonstrated these same lesions map to a common brain circuit, unifying a traditionally heterogeneous patient population. Findings were validated in an independent cohort and the identified SE circuit distinguished brain imaging changes during SE from other lesion etiologies with excellent accuracy (91%), significantly outperforming all other tested maps. With this SE circuit, we identify therapeutic targets for precision therapy that could modulate this circuit. This study demonstrates brain imaging changes in SE converge on a unified brain circuit that could help diagnostic workup of patients in critical care and guide clinical trials of precision therapy for persistent seizures.

neuroscience↗

Structure analysis of human Prion protein involved in Sporadic Fatal Insomnia

Prion disorders are the root cause of Transmissible Spongiform Encephalopathies (TSE), a group of lethal diseases portrayed by progressive neurodegeneration and spongiosis. In recent years, researchers have come to understand that it is not the endogenous presence of Prions itself that causes neurodegeneration, but the amount of prion proteins that accumulates in the nervous tissue, leading them to exert neurotoxicity. More specifically, the cause of these disorders is mapped to several mutations that can bring the prion protein structure to a disordered permanent misfolded state. Our research is focused on Sporadic Fatal Insomnia (sFI), a rare TSE characterized by severe and chronic insomnia, leading to a life expectancy estimation of about two and a half years, from the onset of the first symptoms. The goal of this work was to analyze through computational studies the structure of the native human Prion Protein (PrPnat) and compare it with the toxic form (FI-Prion) which causes disease. Our findings show that the structure of the human mutant FI-Prion, responsible for Sporadic Fatal Insomnia is more flexible than the native human form PrPnat. Specific regions of the mutant seem to fluctuate more freely than the corresponding loops in the native form. We also identified amino acids Tyr128 and Met129 to be the key residues playing a major role in the manifestation of the disease. Therefore, weve learnt that the FI-Prion is more flexible than PrPnat. In addition, we also confirmed that sporadic fatal insomnia is undoubtedly an infectious disease.

bioinformatics↗