Publications by authors named "William J Pottorf"

Introduction: Older patients are at increased risk for hyperkalemia (HK). This study describes the prevalence, recurrence, and clinical and economic burden of HK in Medicare patients admitted to a long-term care (LTC) setting.

Methods: Retrospective cohort study using 100% Medicare Fee-for-Service (FFS) claims identified patients aged ≥ 65 years with index admission between 2017 and 2019 to a LTC setting (skilled nursing, home health, inpatient rehabilitation, or long-term acute care).

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Background: Bipolar I and II represent the most common and severe subtypes of bipolar disorder. Although bipolar I disorder is relatively well studied, the clinical characteristics and response to treatment of patients with bipolar II disorder are less well understood.

Methods: To compare the severity and burden of illness of patients with bipolar II versus bipolar I disorder, baseline demographic, clinical, and quality of life data were examined in 1900 patients with bipolar I and 973 patients with bipolar II depression, who were enrolled in five similarly designed clinical placebo-controlled trials of quetiapine immediate-release and quetiapine extended-release.

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Calcium ions represent universal second messengers within neuronal cells integrating multiple cellular functions, such as release of neurotransmitters, gene expression, proliferation, excitability, and regulation of cell death or apoptotic pathways. The magnitude, duration and shape of stimulation-evoked intracellular calcium ([Ca2+]i) transients are determined by a complex interplay of mechanisms that modulate stimulation-evoked rises in [Ca2+]i that occur with normal neuronal function. Disruption of any of these mechanisms may have implications for the function and health of peripheral neurones during the aging process.

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Ca2+ dysregulation is a hallmark of excitotoxicity, a process that underlies multiple neurodegenerative disorders. The plasma membrane Ca2+ ATPase (PMCA) plays a major role in clearing Ca2+ from the neuronal cytoplasm. Here, we show that the rate of PMCA-mediated Ca2+ efflux from rat hippocampal neurons decreased following treatment with an excitotoxic concentration of glutamate.

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The plasma membrane Ca2+ ATPase (PMCA) plays a major role in clearing Ca2+ from the neuronal cytoplasm. Calmodulin stimulates PMCA activity and for some isoforms this activation persists following clearance of Ca2+ owing to the slow dissociation of calmodulin. We tested the hypothesis that PMCA-mediated Ca2+ efflux from rat dorsal root ganglion (DRG) neurons in culture would remain stimulated following increases in intracellular Ca2+ concentration ([Ca2+]i).

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Neurons are exquisitely sensitive to the duration, amplitude and localization of transient increases in intracellular Ca2+ concentration ([Ca2+]i). Modulation of Ca2+ uptake into the mitochondrion and endoplasmic reticulum, and efflux via the plasma membrane Ca2+ pump and Na+/Ca2+ exchange profoundly affect the shape of [Ca2+]i signals. Ca2+ clearance mechanisms are modulated by other signaling pathways, are sensitive to metabolic state and have a memory of the recent history of cell activation.

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The aging process at the cellular, organ and whole organism levels is in many respects a mystery. A common bias among those who study aging is that cellular homeostasis "generally falls apart". The assumption of a general deterioration in cellular homeostasis does not take into account that many individuals age quite well maintaining even robust physiological and mental functions.

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