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Inhibition Of Calpains By Calpastatin: Implications For Cellular And Functional Damage Following Traumatic Brain Injury, Kathleen M. Schoch

Theses and Dissertations--Physiology

Traumatic brain injury (TBI) is a devastating health problem based on its high incidence, economic burden, and lack of effective pharmacological treatment. Individuals who suffer an injury often experience lifelong disability. TBI results in abrupt, initial cell damage leading to delayed neuronal death. The calcium-activated proteases, calpains, are known to contribute to this secondary neurodegenerative cascade. Prolonged activation of calpains results in proteolysis of numerous cellular substrates including cytoskeletal components, membrane receptors, and cytosolic proteins, contributing to cell demise despite coincident expression of calpastatin, the specific inhibitor of calpains.

A comprehensive analysis using two separate calpastatin transgenic mouse lines was …

Mechanistic Basis For Atrial And Ventricular Arrhythmias Caused By Kcnq1 Mutations, Daniel C. Bartos

Theses and Dissertations--Physiology

Cardiac arrhythmias are caused by a disruption of the normal initiation or propagation of electrical impulses in the heart. Hundreds of mutations in genes encoding ion channels or ion channel regulatory proteins are linked to congenital arrhythmia syndromes that increase the risk for sudden cardiac death. This dissertation focuses on how mutations in a gene (KCNQ1) that encodes a voltage-gated K⁺ ion channel (Kv7.1) can disrupt proper channel function and lead to abnormal repolarization of atrial and ventricular cardiomyocytes.

In the heart, Kv7.1 coassembles with a regulatory protein to conduct the slowly activating delayed rectifier K^{+ …}

Evaluation Of Insulin-Like Growth Factor-1 As A Therapeutic Approach For The Treatment Of Traumatic Brain Injury, Shaun W. Carlson

Theses and Dissertations--Physiology

Traumatic brain injury (TBI) is a prevalent CNS neurodegenerative condition that results in lasting neurological dysfunction, including potentially debilitating cognitive impairments. Despite the advancements in understanding the complex damage that can culminate in cellular dysfunction and loss, no therapeutic treatment has been effective in clinical trials, highlighting that new approaches are desperately needed. A therapy that limits cell death while simultaneously promoting reparative mechanisms, including post-traumatic neurogenesis, in the injured brain may have maximum effectiveness in improving recovery of function after TBI. Insulin-like growth factor-1 (IGF-1) is a potent growth factor that has previously been shown to promote recovery of …