Comorbidities confounding the outcomes of surgery for third window syndrome: Outlier analysis.

Objective: Patients with third window syndrome and superior semicircular canal dehiscence (SSCD) symptoms whose surgical outcomes placed them as outliers were systematically studied to determine comorbidities that were responsible for their poor outcomes due to these confounding factors.

Study Design: Observational analytic case-control study in a tertiary referral center.

Methods: Twelve adult patients with clinical SSCD syndrome underwent surgical management and had outcomes that did not resolve all of their subjective symptoms.

Dynamic Regulation of the Adenosine Kinase Gene during Early Postnatal Brain Development and Maturation.

The ubiquitous metabolic intermediary and nucleoside adenosine is a "master regulator" in all living systems. Under baseline conditions adenosine kinase (ADK) is the primary enzyme for the metabolic clearance of adenosine. By regulating the availability of adenosine, ADK is a critical upstream regulator of complex homeostatic and metabolic networks.

Adenosine Kinase Inhibition Protects against Cranial Radiation-Induced Cognitive Dysfunction.

Clinical radiation therapy for the treatment of CNS cancers leads to unintended and debilitating impairments in cognition. Radiation-induced cognitive dysfunction is long lasting; however, the underlying molecular and cellular mechanisms are still not well established. Since ionizing radiation causes microglial and astroglial activation, we hypothesized that maladaptive changes in astrocyte function might be implicated in radiation-induced cognitive dysfunction.

The Biochemistry and Epigenetics of Epilepsy: Focus on Adenosine and Glycine.

Epilepsy, one of the most prevalent neurological conditions, presents as a complex disorder of network homeostasis characterized by spontaneous non-provoked seizures and associated comorbidities. Currently used antiepileptic drugs have been designed to suppress neuronal hyperexcitability and thereby to suppress epileptic seizures. However, the current armamentarium of antiepileptic drugs is not effective in over 30% of patients, does not affect the comorbidities of epilepsy, and does not prevent the development and progression of epilepsy (epileptogenesis).

Role of Glia in Stress-Induced Enhancement and Impairment of Memory.

Both acute and chronic stress profoundly affect hippocampally-dependent learning and memory: moderate stress generally enhances, while chronic or extreme stress can impair, neural and cognitive processes. Within the brain, stress elevates both norepinephrine and glucocorticoids, and both affect several genomic and signaling cascades responsible for modulating memory strength. Memories formed at times of stress can be extremely strong, yet stress can also impair memory to the point of amnesia.

From unwitnessed fatality to witnessed rescue: Pharmacologic intervention in sudden unexpected death in epilepsy.

The mechanisms of sudden unexpected death in epilepsy (SUDEP) have been difficult to define, as most cases occur unwitnessed, and physiologic recordings have been obtained in only a handful of cases. However, recent data obtained from human cases and experimental studies in animal models have brought us closer to identifying potential mechanisms. Theories of SUDEP should be able to explain how a seizure starting in the forebrain can sometimes lead to changes in brainstem cardiorespiratory control mechanisms.

Parametric transfer function analysis and modeling of blood flow autoregulation in the optic nerve head.

The aim of the study was to establish a parametric transfer function to describe the relationship between ocular perfusion pressure (OPP) and blood flow (BF) in the optic nerve head (ONH). A third-order parametric theoretical model was proposed to describe the ONH OPP-BF relationship within the lower OPP range of the autoregulation curve (< 80 mmHg) based on experimentally induced BF response to a rapid intraocular pressure (IOP) increase in 6 rhesus monkeys. The theoretical and actual data fitted well and suggest that this parametric third-order transfer function can effectively describe both the linear and nonlinear feature in dynamic and static autoregulation in the ONH within the OPP range studied.

MicroRNA responses to focal cerebral ischemia in male and female mouse brain.

Stroke occurs with greater frequency in men than in women across diverse ethnic backgrounds and nationalities. Work from our lab and others have revealed a sex-specific sensitivity to cerebral ischemia whereby males exhibit a larger extent of brain damage resulting from an ischemic event compared to females. Previous studies revealed that microRNA (miRNA) expression is regulated by cerebral ischemia in males; however, no studies to date have examined the effect of ischemia on miRNA responses in females.

Homeostatic control of brain function - new approaches to understand epileptogenesis.

Neuronal excitability of the brain and ongoing homeostasis depend not only on intrinsic neuronal properties, but also on external environmental factors; together these determine the functionality of neuronal networks. Homeostatic factors become critically important during epileptogenesis, a process that involves complex disruption of self-regulatory mechanisms. Here we focus on the bioenergetic homeostatic network regulator adenosine, a purine nucleoside whose availability is largely regulated by astrocytes.