Publications by authors named "John C Mason"

The extensive heterogeneity of biological data poses challenges to analysis and interpretation. Construction of a large-scale mechanistic model of enabled us to integrate and cross-evaluate a massive, heterogeneous dataset based on measurements reported by various groups over decades. We identified inconsistencies with functional consequences across the data, including that the total output of the ribosomes and RNA polymerases described by data are not sufficient for a cell to reproduce measured doubling times, that measured metabolic parameters are neither fully compatible with each other nor with overall growth, and that essential proteins are absent during the cell cycle-and the cell is robust to this absence.

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During the course of a bacterial infection, cells are exposed simultaneously to a range of bacterial and host factors, which converge on the central transcription factor nuclear factor (NF)-κB. How do single cells integrate and process these converging stimuli? Here we tackle the question of how cells process combinatorial signals by making quantitative single-cell measurements of the NF-κB response to combinations of bacterial lipopolysaccharide and the stress cytokine tumor necrosis factor. We found that cells encode the presence of both stimuli via the dynamics of NF-κB nuclear translocation in individual cells, suggesting the integration of NF-κB activity for these stimuli occurs at the molecular and pathway level.

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The technology for building functionally complete or 'whole-cell' biological simulations is rapidly developing. However, the predictive capabilities of these simulations are hindered by the availability of parameter values, which are often difficult or even impossible to obtain experimentally and must therefore be estimated. Using E.

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Tornwaldt's cyst is an uncommon type of nasopharyngeal cyst that may cause clinically significant symptoms. We reviewed reports of 31,855 computed tomography (CT) scans and 21,158 magnetic resonance imaging (MRI) scans to ascertain how many Tornwaldt's cysts were discovered incidentally. These images had been obtained between Jan.

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Objectives/hypothesis: Auditory neuropathy is a relatively recently described pattern of hearing loss characterized by preservation of outer hair cell function despite absent brainstem auditory evoked responses. Intact outer hair cell function is demonstrated by the presence of otoacoustic emissions and/or a measurable cochlear microphonic on electrocochleography, whereas no synchronous neural activity (absent action potentials) is seen on acoustically evoked brainstem auditory evoked response testing. The study reviews the authors' experience with six patients diagnosed with auditory neuropathy, four of whom have undergone cochlear implantation.

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Objectives: The treatment of otogenic sigmoid sinus thrombosis with surgery and antibiotics is well established. However, the role of anticoagulation remains unstudied. The study reviews the signs, symptoms, radiological evaluation, surgical treatment, and medical management of patients with otogenic sigmoid sinus thrombosis treated with or without anticoagulation.

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Objective: To review the safety and efficacy of endoscopic drainage of subperiosteal orbital abscesses (SPOAs) secondary to sinusitis and to evaluate risk factors that may be associated with failure.

Study Design: Retrospective chart review.

Methods: All patients admitted to the University of the Virginia Health System with a diagnosis of SPOA between 1992 and 1999 were reviewed.

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