Publications by authors named "Christopher O'Connell"

Traumatic brain injury (TBI) is a pervasive public health crisis that severely impacts the quality of life of affected individuals. Like peripheral forms of trauma, TBI results from extraordinarily heterogeneous environmental forces being imparted on the cranial space, resulting in heterogeneous disease pathologies. This has made therapies for TBI notoriously difficult to develop, and currently, there are no FDA-approved pharmacotherapies specifically for the acute or chronic treatment of TBI.

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Mild traumatic brain injury (mTBI) is a leading cause of disability in the United States, with neuropsychiatric disturbances such as depression, anxiety, PTSD, and social disturbances being common comorbidities following injury. The molecular mechanisms driving neuropsychiatric complications following neurotrauma are not well understood and current FDA-approved pharmacotherapies employed to ameliorate these comorbidities lack desired efficacy. Concerted efforts to understand the molecular mechanisms of and identify novel drug candidates for treating neurotrauma-elicited neuropsychiatric sequelae are clearly needed.

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Mitochondria play many essential roles in the cell, including energy production, regulation of Ca homeostasis, lipid biosynthesis, and production of reactive oxygen species (ROS). These mitochondria-mediated processes take on specialized roles in neurons, coordinating aerobic metabolism to meet the high energy demands of these cells, modulating Ca signaling, providing lipids for axon growth and regeneration, and tuning ROS production for neuronal development and function. Mitochondrial dysfunction is therefore a central driver in neurodegenerative diseases.

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Introduction: Hazardous alcohol use (HAU), defined as a pattern of alcohol consumption that increases the risk of harmful consequences for the user or others, is associated with an elevated risk of human immunodeficiency virus (HIV) infection and poor health outcomes. We describe the association between people living with HIV (PLHIV) who report HAU and key HIV indicators. Gaps in current literature in estimating HAU on HIV outcomes at the regional level of Eastern and Southern Africa still exist and our analysis aims to address this issue.

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Acceleration/deceleration forces are a common component of various causes of mild traumatic brain injury (mTBI) and result in strain and shear forces on brain tissue. A small quantifiable volume dubbed the compensatory reserve volume (CRV) permits energy transmission to brain tissue during acceleration/deceleration events. The CRV is principally regulated by cerebral blood flow (CBF) and CBF is primarily determined by the concentration of inspired carbon dioxide (CO).

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With the evolution of modern warfare and the increased use of improvised explosive devices (IEDs), there has been an increase in blast-induced traumatic brain injuries (bTBI) among military personnel and civilians. The increased prevalence of bTBI necessitates bTBI models that result in a properly scaled injury for the model organism being used. The primary laboratory model for bTBI is the shock tube, wherein a compressed gas ruptures a thin membrane, generating a shockwave.

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The monoamine neurotransmitter serotonin (5-HT) is important for the regulation of behavior, and aberrations in 5-HT signaling are linked to several neuropsychiatric and neurodevelopmental disorders. 5-HT signaling is dependent on and tightly regulated by the functional activity of the 5-HT transporter (SERT). Neurotrauma is known to structurally and functionally impact 5-HT neuronal tracts and 5-HT signaling; however, the extent to which various forms of neurotrauma alter homeostatic 5-HT signaling through the modulation of SERT expression and/or functional uptake capacity is currently not well characterized.

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The objective of this study was to determine if certified electronic health record technology (CEHRT) can be used to identify and refer patients with prediabetes to lifestyle change programs (LCPs) recognized by the National Diabetes Prevention Program (DPP). This pilot utilized a prediabetes registry, patient portal, and clinical decision support to increase referrals. Data from 36 primary care providers showed 4930 patients were eligible for DPP LCP, 293 referrals were generated, compared to 20 referrals in the baseline period, and 116 patients enrolled.

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Approximately 1 in 3 American adults has prediabetes, a condition characterized by blood glucose levels that are above normal, not in the type 2 diabetes ranges, and that increases the risk of developing type 2 diabetes. Evidence-based treatments can be used to prevent or delay type 2 diabetes in adults with prediabetes. The American Medical Association (AMA) has collaborated with health care organizations across the country to build sustainable diabetes prevention strategies.

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Metal-assisted chemical etching (MacEtch) has been established as a low-cost, benchtop, and versatile method for large-scale fabrication of semiconductor nanostructures and has been heralded as an alternative to conventional top-down approaches such as reactive-ion etching. However, extension of this technique to ternary III-V compound semiconductor alloys and heteroepitaxial systems has remained relatively unexplored. Here, Au-assisted and inverse-progression MacEtch (I-MacEtch) of the heteroepitaxial InGaP/GaAs material system is demonstrated, along with a method for fabricating suspended InGaP nanofoils of tunable thickness in solutions of hydrofluoric acid (HF) and hydrogen peroxide (HO).

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Autofluorescent bovine serum albumin (BSA) hydrogel microspheres were prepared through the spray-drying of glutaraldehyde cross-linked BSA nanoparticles and then used for a proteinase K based degradation study in an aqueous solution. Experimental results and empirical models are presented to characterize the kinetics of BSA hydrogel microsphere degradation, as well as the accompanying release of synthesized fluorophore. The BSA gel degradation dynamics is primarily controlled by the concentration of proteinase K within the Tris buffer.

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Extreme heat events will become more frequent under anthropogenic climate change, especially in Mediterranean ecosystems. Microhabitats can considerably moderate (buffer) the effects of extreme weather events and hence facilitate the persistence of some components of the biodiversity. We investigate the microclimatic moderation provided by two important microhabitats (cavities formed by the leaves of the grass-tree Xanthorrhoea semiplana F.

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Kinetochores attach chromosomes to the spindle microtubules and signal the spindle assembly checkpoint to delay mitotic exit until all chromosomes are attached. Light microscopy approaches aimed to indirectly determine distances between various proteins within the kinetochore (termed Delta) suggest that kinetochores become stretched by spindle forces and compact elastically when the force is suppressed. Low Delta is believed to arrest mitotic progression in taxol-treated cells.

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Mitotic spindle formation relies on the stochastic capture of microtubules at kinetochores. Kinetochore architecture affects the efficiency and fidelity of this process with large kinetochores expected to accelerate assembly at the expense of accuracy, and smaller kinetochores to suppress errors at the expense of efficiency. We demonstrate that on mitotic entry, kinetochores in cultured human cells form large crescents that subsequently compact into discrete structures on opposite sides of the centromere.

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Objective: To determine if any monotherapy drug treatment has robust efficacy to treat comorbid bipolar disorder and chronic pain.

Data Sources: The American Psychiatric Association (APA) treatment guidelines for bipolar mood disorder and the 2012 Cochrane database for pain disorders.

Study Selection: We relied on the treatment guides to determine if the drugs that are APA guideline-supported to treat bipolar disorder have supporting data from the Cochrane database for chronic pain.

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Airway multiciliated epithelial cells play crucial roles in the mucosal defense system, but their differentiation process remains poorly understood. Mice lacking the basal body component Chibby (Cby) exhibit impaired mucociliary transport caused by defective ciliogenesis, resulting in chronic airway infection. In this paper, using primary cultures of mouse tracheal epithelial cells, we show that Cby facilitates basal body docking to the apical cell membrane through proper formation of ciliary vesicles at the distal appendage during the early stages of ciliogenesis.

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Background: Nursing practice is complex, as nurses are challenged by increasingly intricate moral and ethical judgments. Inadequately studied in underrepresented groups in nursing, moral distress is a serious problem internationally for healthcare professionals with deleterious effects to patients, nurses, and organizations. Moral distress among nurses has been shown to contribute to decreased job satisfaction and increased turnover, withdrawal from patients, physical and psychological symptoms, and intent to leave current position or to leave the profession altogether.

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Super-resolution microscopy overcomes diffraction to generate images with superior resolution compared to conventional light microscopy. Localization-based super-resolution methods result in up to ten-fold improvement in resolution by determining the positions of fluorescent molecules with sub-pixel accuracy. This process critically depends on controlled emission at the level of individual fluorophores so that fluorescence is non-overlapping, allowing for accurate centroid determination of diffraction-limited spots by Gaussian fitting of the pixel intensities.

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Kinetochores are complex macromolecular assemblies that link chromosomes to the mitotic spindle, mediate forces for chromosome motion, and generate the checkpoint signal delaying anaphase onset until all chromosomes are incorporated into the spindle. Proper execution of these functions depends on precise interactions between kinetochores and microtubules. While the molecular composition of the kinetochore is well described, structural organization of this organelle at the molecular and atomic levels is just beginning to emerge.

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BubR1 functions as a crucial component that monitors proper chromosome congression and mitotic timing during cell division. We investigated molecular regulation of BubR1 and found that BubR1 was modified by an unknown post-translation mechanism during the cell cycle, resulting in a significant mobility shift on denaturing gels. We termed it BubR1-M as the nature of modification was not characterized.

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Background: FDA-approved for the correction of moderate-to-severe facial wrinkles and folds, small gel-particle hyaluronic acid (SGP-HA, Restylane, Medicis Aesthetics, Inc., Scottsdale, AZ) and large gel-particle hyaluronic acid (LGP-HA, Perlane, Medicis Aesthetics, Inc., Scottsdale, AZ) were studied to evaluate their safety for the correction of oral commissures, marionette lines, upper perioral rhytides and nasolabial folds (NLFs).

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Error-free chromosome segregation requires stable attachment of sister kinetochores to the opposite spindle poles (amphitelic attachment). Exactly how amphitelic attachments are achieved during spindle assembly remains elusive. We employed photoactivatable GFP and high-resolution live-cell confocal microscopy to visualize complete 3D movements of individual kinetochores throughout mitosis in nontransformed human cells.

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