Publications by authors named "Dent M"

For many years, a method that allowed systemic toxicity safety assessments to be conducted without generating new animal test data, seemed out of reach. However, several different research groups and regulatory authorities are beginning to use a variety of in silico, in chemico and in vitro techniques to inform safety decisions. To manage this transition to animal-free safety assessments responsibly, it is important to ensure that the level of protection offered by a safety assessment based on new approach methodologies (NAMs), is at least as high as that provided by a safety assessment based on traditional animal studies.

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Although lithium-sulfur (Li-S) batteries offer a high theoretical energy density, shuttling of dissolved sulfur and polysulfides is a major factor limiting the specific capacity, energy density, and cyclability of Li-S batteries with a liquid electrolyte. Cathode host materials with a microstructure to restrict the migration of active material may not totally eliminate the shuttling effect or may create additional problems that limit the full dissolution and redox conversion of all active cathode materials. Selecting a cathode coating binder with a multifunctional role offers a universal solution suitable for various cathode hosts.

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The transcription factor CooA is a CRP/FNR (cAMP receptor protein/ fumarate and nitrate reductase) superfamily protein that uses heme to sense carbon monoxide (CO). Allosteric activation of CooA in response to CO binding is currently described as a series of discrete structural changes, without much consideration for the potential role of protein dynamics in the process of DNA binding. This work uses site-directed spin-label electron paramagnetic resonance spectroscopy (SDSL-EPR) to probe slow timescale (μs-ms) conformational dynamics of CooA with a redox-stable nitroxide spin label, and IR spectroscopy to probe the environment at the CO-bound heme.

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Proteins are acknowledged as the phenotypical manifestation of the genotype, because protein-coding genes carry the information for the strings of amino acids that constitute the proteins. It is widely accepted that protein function depends on the corresponding "native" structure or folding achieved within the cell, and that native protein folding corresponds to the lowest free energy minimum for a given protein. However, protein folding within the cell is a non-deterministic dissipative process that from the same input may produce different outcomes, thus conformational heterogeneity of folded proteins is the rule and not the exception.

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The present investigation fits the reaction kinetics of a lithium-sulfur (Li-S) battery with polar electrolyte employing a novel two-phase continuum multipore model. The continuum two-phase model considers processes in both the liquid electrolyte phase and the solid precipitates phase, where the diffusion coefficients of the Li ions in a solvent-softened solid state are determined from molecular dynamics simulations. Solubility experiments yield the saturation concentration of sulfur and lithium sulfides in the polar electrolyte employed in this study.

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Background: Standardised guidelines for stance are used to improve interobserver reliability in anthropometric measurements in clinical practice. A key feature of the stance in Pilates is the 'drawing in and up' of the abdomen. The aim of this study was to study the impact of the Pilates stance on height, waist circumference and interscapular distance, compared to that recommended in clinical practice.

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Next Generation Risk Assessment (NGRA) is an exposure-led approach to safety assessment that uses New Approach Methodologies (NAMs). Application of NGRA has been largely restricted to assessments of consumer use of cosmetics and is not currently implemented in occupational safety assessments, e.g.

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Noise-induced hearing loss interacts with age, sex, and listening conditions to affect individuals' perception of ecologically relevant stimuli like speech. The present experiments assessed the impact of age and sex on vocalization detection by noise-exposed mice trained to detect a downsweep or complex ultrasonic vocalization in quiet or in the presence of a noise background. Daily thresholds before and following intense noise exposure were collected longitudinally and compared across several factors.

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Neuroglobin is a hemoprotein expressed in several nervous system cell lineages with yet unknown physiological functions. Neuroglobin presents a very similar structure to that of the related globins hemoglobin and myoglobin, but shows an hexacoordinate heme as compared to the pentacoordinated heme of myoglobin and hemoglobin. While several reactions of neuroglobin have been characterized , the relative importance of most of those reactions is yet undefined.

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Nitric oxide ( NO) interactions with biological thiols play crucial, but incompletely determined, roles in vascular signalling and other biological processes. Here, we highlight two recently proposed signalling paradigms: (1) the formation of a vasodilating labile nitrosyl ferrous haem (NO-ferrohaem) facilitated by thiols via thiyl radical generation and (2) polysulfides/persulfides and their interaction with NO. We also describe the specific (bio)chemical routes in which NO and thiols react to form S-nitrosothiols, a broad class of small molecules, and protein post-translational modifications that can influence protein function through catalytic site or allosteric structural changes.

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Nitric oxide (NO) is an endogenously produced signaling molecule that regulates blood flow and platelet activation. However, intracellular and intravascular diffusion of NO are limited by scavenging reactions with several hemoproteins, raising questions as to how free NO can signal in hemoprotein-rich environments. We explore the hypothesis that NO can be stabilized as a labile ferrous heme-nitrosyl complex (Fe-NO, NO-ferroheme).

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Background: Neuroblastoma is an embryonal cancer of the developing sympathetic nervous system. The genetic contribution of rare pathogenic or likely pathogenic germline variants in patients without a family history remains unclear.

Methods: Germline DNA sequencing was performed on 786 neuroblastoma patients.

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Estimating human exposure in the safety assessment of chemicals is crucial. Physiologically based kinetic (PBK) models which combine information on exposure, physiology, and chemical properties, describing the absorption, distribution, metabolism, and excretion (ADME) processes of a chemical, can be used to calculate internal exposure metrics such as maximum concentration and area under the concentration-time curve in plasma or tissues of a test chemical in next-generation risk assessment. This article demonstrates the development of PBK models for 3 UV filters, specifically octyl methoxycinnamate, octocrylene, and 4-methylbenzylidene camphor.

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Carbon monoxide (CO) poisoning leads to 50,000-100,000 emergency room visits and 1,500-2,000 deaths each year in the United States alone. Even with treatment, survivors often suffer from long-term cardiac and neurocognitive deficits, highlighting a clear unmet medical need for novel therapeutic strategies that reduce morbidity and mortality associated with CO poisoning. This review examines the prevalence and impact of CO poisoning and pathophysiology in humans and highlights recent advances in therapeutic strategies that accelerate CO clearance and mitigate toxicity.

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Lipid membranes are crucial for cellular integrity and regulation, and tight control of their structural and mechanical properties is vital to ensure that they function properly. Fluorescent probes sensitive to the membrane's microenvironment are useful for investigating lipid membrane properties; however, there is currently a lack of quantitative correlation between the exact parameters of lipid organization and a readout from these dyes. Here, we investigate this relationship for "molecular rotors", or microviscosity sensors, by simultaneously measuring their fluorescence lifetime to determine the membrane viscosity, while using X-ray diffraction to determine the membrane's structural properties.

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Objective: To develop, implement, and evaluate an educational program to improve nurses' management of the second stage of labor.

Design: Evidence-based practice project guided by the Iowa Model-Revised.

Setting: Acute care teaching hospital in central California averaging 2,100 births/year with 12 labor, delivery, and recovery rooms and a Level III nursery.

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Essential oils from Mediterranean wild plants are widely used, but the hydrodistillation residues produced in parallel with these essential oils are significantly understudied and underexploited. Since there are only fragmentary data in the literature, we have, for the first time, systematically analyzed the chemical composition of the by-products obtained after hydrodistillation of sage, bay laurel, and rosemary leaves, i.e.

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The risk assessment of endocrine-disrupting chemicals (EDCs) greatly relies on in vitro screening. A 3-dimensional (3D) in vitro prostate model that can reflect physiologically-relevant prostate epithelial and stromal crosstalk can significantly advance the current androgen assessment. This study built a prostate epithelial and stromal co-culture microtissue model with BHPrE and BHPrS cells in scaffold-free hydrogels.

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Carbon monoxide (CO) serves as a source of energy and carbon for a diverse set of microbes found in anaerobic and aerobic environments. The enzymes that bacteria and archaea use to oxidize CO depend upon complex metallocofactors that require accessory proteins for assembly and proper function. This complexity comes at a high energetic cost and necessitates strict regulation of CO metabolic pathways in facultative CO metabolizers to ensure that gene expression occurs only when CO concentrations and redox conditions are appropriate.

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Cholera toxin B subunit (CTB) is a potent immunomodulator exploitable in mucosal vaccine and immunotherapeutic development. To aid in the characterization of pleiotropic biological functions of CTB and its variants, we generated a panel of anti-CTB monoclonal antibodies (mAbs). By ELISA and surface plasmon resonance, two mAbs, 7A12B3 and 9F9C7, were analyzed for their binding affinities to cholera holotoxin (CTX), CTB, and EPICERTIN: a recombinant CTB variant possessing mucosal healing activity.

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In this study, we monitor the dissolution of sulfur and sulfides in electrolyte solvents for lithium-sulfur (Li-S) and sodium-sulfur (Na-S) batteries. The first aim of this research is to assemble a comprehensive set of data on solubilities and dissolution kinetics that may be used in the simulation of battery cycling. The investigation also offers important insights to address key bottlenecks in the development and commercialization of metal-sulfur batteries, including the incomplete dissolution of sulfur in discharge and insoluble low-order sulfides in charge, the probability of shuttling of soluble polysulfides, and the pausing of the redox reactions in precipitated low order sulfides depending on their degree of solid state.

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Importance: Neuroblastoma accounts for 12% of childhood cancer deaths. The genetic contribution of rare pathogenic germline variation in patients without a family history remains unclear.

Objective: To define the prevalence, spectrum, and clinical significance of pathogenic germline variation in cancer predisposition genes (CPGs) in neuroblastoma patients.

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Nitric oxide (NO) is an endogenously produced physiological signaling molecule that regulates blood flow and platelet activation. However, both the intracellular and intravascular diffusion of NO is severely limited by scavenging reactions with hemoglobin, myoglobin, and other hemoproteins, raising unanswered questions as to how free NO can signal in hemoprotein-rich environments, like blood and cardiomyocytes. We explored the hypothesis that NO could be stabilized as a ferrous heme-nitrosyl complex (Fe -NO, NO-ferroheme) either in solution within membranes or bound to albumin.

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Article Synopsis
  • Experimental outcomes in animal noise studies can be influenced by various non-acoustic factors including subject-related traits like species, age, sex, and body weight.
  • The study focused on CBA/CaJ mice and found that factors such as sex, body mass, age at exposure, and timing of measurements significantly affected auditory brainstem response (ABR) thresholds.
  • Differences in ABR thresholds were noted between noise-exposed and unexposed mice, suggesting that these variables might explain inconsistent results seen in different studies or within the same lab.
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I.v. administration of a high-affinity carbon monoxide-binding (CO-binding) molecule, recombinant neuroglobin, can improve survival in CO poisoning mouse models.

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