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1.
Cell ; 184(11): 2955-2972.e25, 2021 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-34019795

RESUMEN

Natural antibodies (Abs) can target host glycans on the surface of pathogens. We studied the evolution of glycan-reactive B cells of rhesus macaques and humans using glycosylated HIV-1 envelope (Env) as a model antigen. 2G12 is a broadly neutralizing Ab (bnAb) that targets a conserved glycan patch on Env of geographically diverse HIV-1 strains using a unique heavy-chain (VH) domain-swapped architecture that results in fragment antigen-binding (Fab) dimerization. Here, we describe HIV-1 Env Fab-dimerized glycan (FDG)-reactive bnAbs without VH-swapped domains from simian-human immunodeficiency virus (SHIV)-infected macaques. FDG Abs also recognized cell-surface glycans on diverse pathogens, including yeast and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike. FDG precursors were expanded by glycan-bearing immunogens in macaques and were abundant in HIV-1-naive humans. Moreover, FDG precursors were predominately mutated IgM+IgD+CD27+, thus suggesting that they originated from a pool of antigen-experienced IgM+ or marginal zone B cells.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , VIH-1/inmunología , Fragmentos Fab de Inmunoglobulinas/inmunología , Polisacáridos/inmunología , SARS-CoV-2/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , Animales , Linfocitos B/inmunología , Anticuerpos ampliamente neutralizantes/inmunología , COVID-19/inmunología , Dimerización , Epítopos/inmunología , Glicosilación , Anticuerpos Anti-VIH/inmunología , Infecciones por VIH/inmunología , Humanos , Fragmentos Fab de Inmunoglobulinas/química , Macaca mulatta , Polisacáridos/química , Receptores de Antígenos de Linfocitos B/química , Virus de la Inmunodeficiencia de los Simios/genética , Vacunas/inmunología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/química , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética
2.
Proc Natl Acad Sci U S A ; 121(32): e2314087121, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39083421

RESUMEN

Invasive fungal diseases are a major threat to human health, resulting in more than 1.5 million annual deaths worldwide. The arsenal of antifungal therapeutics remains limited and is in dire need of drugs that target additional biosynthetic pathways that are absent from humans. One such pathway involves the biosynthesis of trehalose. Trehalose is a disaccharide that is required for pathogenic fungi to survive in their human hosts. In the first step of trehalose biosynthesis, trehalose-6-phosphate synthase (Tps1) converts UDP-glucose and glucose-6-phosphate to trehalose-6-phosphate. Here, we report the structures of full-length Cryptococcus neoformans Tps1 (CnTps1) in unliganded form and in complex with uridine diphosphate and glucose-6-phosphate. Comparison of these two structures reveals significant movement toward the catalytic pocket by the N terminus upon ligand binding and identifies residues required for substrate binding, as well as residues that stabilize the tetramer. Intriguingly, an intrinsically disordered domain (IDD), which is conserved among Cryptococcal species and closely related basidiomycetes, extends from each subunit of the tetramer into the "solvent" but is not visible in density maps. We determined that the IDD is not required for C. neoformans Tps1-dependent thermotolerance and osmotic stress survival. Studies with UDP-galactose highlight the exquisite substrate specificity of CnTps1. In toto, these studies expand our knowledge of trehalose biosynthesis in Cryptococcus and highlight the potential of developing antifungal therapeutics that disrupt the synthesis of this disaccharide or the formation of a functional tetramer and the use of cryo-EM in the structural characterization of CnTps1-ligand/drug complexes.


Asunto(s)
Antifúngicos , Cryptococcus neoformans , Glucosiltransferasas , Trehalosa , Cryptococcus neoformans/enzimología , Cryptococcus neoformans/metabolismo , Cryptococcus neoformans/genética , Glucosiltransferasas/metabolismo , Glucosiltransferasas/genética , Antifúngicos/farmacología , Antifúngicos/química , Antifúngicos/metabolismo , Trehalosa/metabolismo , Trehalosa/análogos & derivados , Trehalosa/biosíntesis , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/química , Modelos Moleculares , Humanos , Dominio Catalítico , Cristalografía por Rayos X
3.
Proc Natl Acad Sci U S A ; 119(44): e2205548119, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36279443

RESUMEN

Air pollution levels in the United States have decreased dramatically over the past decades, yet national racial-ethnic exposure disparities persist. For ambient fine particulate matter ([Formula: see text]), we investigate three emission-reduction approaches and compare their optimal ability to address two goals: 1) reduce the overall population average exposure ("overall average") and 2) reduce the difference in the average exposure for the most exposed racial-ethnic group versus for the overall population ("national inequalities"). We show that national inequalities in exposure can be eliminated with minor emission reductions (optimal: ~1% of total emissions) if they target specific locations. In contrast, achieving that outcome using existing regulatory strategies would require eliminating essentially all emissions (if targeting specific economic sectors) or is not possible (if requiring urban regions to meet concentration standards). Lastly, we do not find a trade-off between the two goals (i.e., reducing overall average and reducing national inequalities); rather, the approach that does the best for reducing national inequalities (i.e., location-specific strategies) also does as well as or better than the other two approaches (i.e., sector-specific and meeting concentration standards) for reducing overall averages. Overall, our findings suggest that incorporating location-specific emissions reductions into the US air quality regulatory framework 1) is crucial for eliminating long-standing national average exposure disparities by race-ethnicity and 2) can benefit overall average exposures as much as or more than the sector-specific and concentration-standards approaches.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Estados Unidos , Humanos , Contaminantes Atmosféricos/análisis , Etnicidad , Exposición a Riesgos Ambientales/prevención & control , Exposición a Riesgos Ambientales/análisis , Contaminación del Aire/prevención & control , Contaminación del Aire/análisis , Material Particulado/análisis
4.
Proc Natl Acad Sci U S A ; 119(37): e2123092119, 2022 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-36067314

RESUMEN

Levels of the cellular dNTPs, the direct precursors for DNA synthesis, are important for DNA replication fidelity, cell cycle control, and resistance against viruses. Escherichia coli encodes a dGTPase (2'-deoxyguanosine-5'-triphosphate [dGTP] triphosphohydrolase [dGTPase]; dgt gene, Dgt) that establishes the normal dGTP level required for accurate DNA replication but also plays a role in protecting E. coli against bacteriophage T7 infection by limiting the dGTP required for viral DNA replication. T7 counteracts Dgt using an inhibitor, the gene 1.2 product (Gp1.2). This interaction is a useful model system for studying the ongoing evolutionary virus/host "arms race." We determined the structure of Gp1.2 by NMR spectroscopy and solved high-resolution cryo-electron microscopy structures of the Dgt-Gp1.2 complex also including either dGTP substrate or GTP coinhibitor bound in the active site. These structures reveal the mechanism by which Gp1.2 inhibits Dgt and indicate that Gp1.2 preferentially binds the GTP-bound form of Dgt. Biochemical assays reveal that the two inhibitors use different modes of inhibition and bind to Dgt in combination to yield enhanced inhibition. We thus propose an in vivo inhibition model wherein the Dgt-Gp1.2 complex equilibrates with GTP to fully inactivate Dgt, limiting dGTP hydrolysis and preserving the dGTP pool for viral DNA replication.


Asunto(s)
Bacteriófago T7 , Proteínas de Escherichia coli , Escherichia coli , GTP Fosfohidrolasas , Guanosina Trifosfato , Proteínas Virales , Bacteriófago T7/fisiología , Microscopía por Crioelectrón , Replicación del ADN , ADN Viral/metabolismo , Escherichia coli/enzimología , Escherichia coli/virología , Proteínas de Escherichia coli/química , GTP Fosfohidrolasas/metabolismo , Guanosina Trifosfato/metabolismo , Conformación Proteica , Proteínas Virales/química , Replicación Viral
5.
J Biol Chem ; 299(3): 102946, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36707054

RESUMEN

Voltage-gated sodium and calcium channels are distinct, evolutionarily related ion channels that achieve remarkable ion selectivity despite sharing an overall similar structure. Classical studies have shown that ion selectivity is determined by specific binding of ions to the channel pore, enabled by signature amino acid sequences within the selectivity filter (SF). By studying ancestral channels in the pond snail (Lymnaea stagnalis), Guan et al. showed in a recent JBC article that this well-established mechanism can be tuned by alternative splicing, allowing a single CaV3 gene to encode both a Ca2+-permeable and an Na+-permeable channel depending on the cellular context. These findings shed light on mechanisms that tune ion selectivity in physiology and on the evolutionary basis of ion selectivity.


Asunto(s)
Empalme Alternativo , Canales de Calcio , Canales de Sodio Activados por Voltaje , Animales , Secuencia de Aminoácidos , Calcio/metabolismo , Canales de Calcio/metabolismo , Iones/metabolismo , Caracoles/metabolismo , Canales de Sodio Activados por Voltaje/metabolismo
6.
J Gen Intern Med ; 39(Suppl 1): 127-135, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38252241

RESUMEN

BACKGROUND: Patient portals play an increasingly critical role in engaging patients in their health care. They have the potential to significantly impact the health of those living with chronic diseases, such as HIV, for whom consistent care engagement is both critical and complex. OBJECTIVE: The primary aim was to examine the longitudinal relationships between individual portal tool use and health-related outcomes in patients living with HIV. DESIGN: Retrospective cohort study using electronic health record data to examine the relationship between patient portal tool use and key HIV-specific, health-related outcomes in patients engaged in care in the Veterans Health Administration (VA) through the application of marginal structural models. PARTICIPANTS: A national sample of patients living with HIV (PLWH) active in VA care who were registered to use the VA's patient portal, My HealtheVet (MHV; n = 18,390) between 10/1/2012 and 4/1/2017. MAIN MEASURES: The MHV tools examined were prescription refill (including prescription refill of an antiretroviral (ART) medication and any medication), secure messaging, view appointments, and view labs. Primary outcomes were viral load test receipt, viral load suppression, and ART medication adherence (measured as proportion of days covered). KEY RESULTS: The use of prescription refill for any medication or for ART was positively associated with ART adherence. Secure messaging was positively associated with ART adherence but not with viral load test receipt or viral load suppression. The use of view appointments was positively associated with ART adherence and viral load test receipt but not viral load suppression. The use of view labs was positively associated with viral load suppression but not ART adherence or viral load test receipt. CONCLUSIONS: These findings highlight the valuable role patient portals may play in improving health-related outcomes among PLWH and have implications for patients living with other types of chronic disease.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Portales del Paciente , Comportamiento del Uso de la Herramienta , Humanos , Fármacos Anti-VIH/uso terapéutico , Estudios Retrospectivos , Carga Viral , Infecciones por VIH/tratamiento farmacológico , Cumplimiento de la Medicación
7.
J Gen Intern Med ; 39(Suppl 1): 97-105, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38252250

RESUMEN

BACKGROUND: Innovative technology can enhance patient access to healthcare but must be successfully implemented to be effective. OBJECTIVE: We evaluated Department of Veterans Affairs' (VA's) implementation of My VA Images, a direct-to-patient asynchronous teledermatology mobile application enabling established dermatology patients to receive follow-up care remotely instead of in-person. DESIGN /PARTICIPANTS/APPROACH: Following pilot testing at 3 facilities, the app was introduced to 28 facilities (4 groups of 7) every 3 months using a stepped-wedge cluster-randomized design. Using the Organizational Theory of Implementation Effectiveness, we examined the app's implementation using qualitative and quantitative data consisting of encounter data from VA's corporate data warehouse; app usage from VA's Mobile Health database; bi-monthly reports from facility representatives; phone interviews with clinicians; and documented communications between the operational partner and facility staff. KEY RESULTS: Implementation policies and practices included VA's vision to expand home telehealth and marketing/communication strategies. The COVID-19 pandemic dominated the implementation climate by stressing staffing, introducing competing demands, and influencing stakeholder attitudes to the app, including its fit to their values. These factors were associated with mixed implementation effectiveness, defined as high quality consistent use. Nineteen of 31 exposed facilities prepared to use the app; 10 facilities used it for actual patient care, 7 as originally intended. Residents, nurse practitioners, and physician assistants were more likely than attendings to use the app. Facilities exposed to the app pre-pandemic were more likely to use and sustain the new process. CONCLUSIONS: Considerable heterogeneity existed in implementing mobile teledermatology, despite VA's common mission, integrated healthcare system, and stakeholders' broad interest. Identifying opportunities to target favorable facilities and user groups (such as teaching facilities and physician extenders, respectively) while addressing internal implementation barriers including incomplete integration with the electronic health record as well as inadequate staffing may help optimize the initial impact of direct-to-patient telehealth. The COVID pandemic was a notable extrinsic barrier. CLINICAL TRIALS REGISTRATION: NCT03241589.


Asunto(s)
COVID-19 , Aplicaciones Móviles , Telemedicina , Humanos , Pandemias
8.
Artículo en Inglés | MEDLINE | ID: mdl-38019094

RESUMEN

RATIONALE: Particulate matter ≤2.5µm (PM2.5) is associated with adverse outcomes in fibrotic interstitial lung disease (fILD), but the impact of ultrafine particulates (UFPs; aerodynamic diameter ≤100nm) remains unknown. OBJECTIVE: To evaluate UFP associations with clinical outcomes in fILD. METHODS: Multicenter, prospective cohort study enrolling patients with fILD from the University of Pittsburgh Simmons Center and Pulmonary Fibrosis Foundation Patient Registry (PFF-PR). Using a national-scale UFP model, we linked exposures using three approaches in Simmons (residential address geocoordinates, zip centroid geocoordinates, zip average) and two in PFF-PR where only 5-digit zip code was available (zip centroid, zip average). We tested UFP associations with transplant-free survival using multivariable Cox, baseline percent predicted forced vital capacity (FVC) and diffusion capacity of the lung (DLCO) using multivariable linear regressions, and decline in FVC and DLCO using linear mixed models, adjusting for age, sex, smoking, race, socioeconomic status, site, PM2.5, and nitrogen dioxide. RESULTS: Annual mean outdoor UFP levels for 2017 were estimated for 1416 Simmons and 1919 PFF-PR patients. Increased UFP level was associated with transplant-free survival in fully-adjusted Simmons residential address models (HR=1.08 per 1000 particles/cm3, 95%CI 1.01-1.15, p=0.02), but not PFF-PR models, which used less precise linkage approaches. Higher UFP was associated with lower baseline FVC and more rapid FVC decline in Simmons. CONCLUSIONS: Increased UFP exposure was associated with transplant-free survival and lung function in the cohort with precise residential location linkage. This work highlights the need for more robust regulatory networks to study the health effects of UFPs nationwide.

9.
Proc Natl Acad Sci U S A ; 118(37)2021 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-34493674

RESUMEN

Disparity in air pollution exposure arises from variation at multiple spatial scales: along urban-to-rural gradients, between individual cities within a metropolitan region, within individual neighborhoods, and between city blocks. Here, we improve on existing capabilities to systematically compare urban variation at several scales, from hyperlocal (<100 m) to regional (>10 km), and to assess consequences for outdoor air pollution experienced by residents of different races and ethnicities, by creating a set of uniquely extensive and high-resolution observations of spatially variable pollutants: NO, NO2, black carbon (BC), and ultrafine particles (UFP). We conducted full-coverage monitoring of a wide sample of urban and suburban neighborhoods (93 km2 and 450,000 residents) in four counties of the San Francisco Bay Area using Google Street View cars equipped with the Aclima mobile platform. Comparing scales of variation across the sampled population, greater differences arise from localized pollution gradients for BC and NO (pollutants dominated by primary sources) and from regional gradients for UFP and NO2 (pollutants dominated by secondary contributions). Median concentrations of UFP, NO, and NO2 are, for Hispanic and Black populations, 8 to 30% higher than the population average; for White populations, average exposures to these pollutants are 9 to 14% lower than the population average. Systematic racial/ethnic disparities are influenced by regional concentration gradients due to sharp contrasts in demographic composition among cities and urban districts, while within-group extremes arise from local peaks. Our results illustrate how detailed and extensive fine-scale pollution observations can add new insights about differences and disparities in air pollution exposures at the population scale.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Etnicidad/estadística & datos numéricos , Disparidades en el Estado de Salud , Aplicaciones Móviles/estadística & datos numéricos , Planificación Social , Remodelación Urbana , Ciudades , Monitoreo del Ambiente/instrumentación , Humanos
10.
Proc Natl Acad Sci U S A ; 118(20)2021 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-33972419

RESUMEN

Agriculture is a major contributor to air pollution, the largest environmental risk factor for mortality in the United States and worldwide. It is largely unknown, however, how individual foods or entire diets affect human health via poor air quality. We show how food production negatively impacts human health by increasing atmospheric fine particulate matter (PM2.5), and we identify ways to reduce these negative impacts of agriculture. We quantify the air quality-related health damages attributable to 95 agricultural commodities and 67 final food products, which encompass >99% of agricultural production in the United States. Agricultural production in the United States results in 17,900 annual air quality-related deaths, 15,900 of which are from food production. Of those, 80% are attributable to animal-based foods, both directly from animal production and indirectly from growing animal feed. On-farm interventions can reduce PM2.5-related mortality by 50%, including improved livestock waste management and fertilizer application practices that reduce emissions of ammonia, a secondary PM2.5 precursor, and improved crop and animal production practices that reduce primary PM2.5 emissions from tillage, field burning, livestock dust, and machinery. Dietary shifts toward more plant-based foods that maintain protein intake and other nutritional needs could reduce agricultural air quality-related mortality by 68 to 83%. In sum, improved livestock and fertilization practices, and dietary shifts could greatly decrease the health impacts of agriculture caused by its contribution to reduced air quality.


Asunto(s)
Agricultura/normas , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Alimentos/normas , Estado de Salud , Material Particulado/análisis , Agricultura/métodos , Agricultura/estadística & datos numéricos , Amoníaco/análisis , Animales , Productos Agrícolas/metabolismo , Enfermedad/etiología , Monitoreo del Ambiente/métodos , Monitoreo del Ambiente/estadística & datos numéricos , Fertilizantes , Geografía , Humanos , Ganado/metabolismo , Mortalidad/tendencias , Material Particulado/efectos adversos , Estados Unidos
11.
Am J Otolaryngol ; 45(6): 104427, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39106688

RESUMEN

OBJECTIVE: To build upon existing literature regarding growth rate of asymptomatic, incidentally found paranasal sinus (PNS) osteomas, evaluate potential factors associated with growth rate and present an argument for how to follow up. METHODS: At our institution, EPIC SlicerDicer was used to screen imaging studies using keyword 'osteoma' and included patients with at least 2 imaging studies 6 months apart that both demonstrated a PNS osteoma(s). Imaging studies with the largest time interval were selected. Non-PNS osteomas were excluded. RESULTS: 47 patients that fit this criterion with a median duration of interval imaging of 35.9 months. Growth rate was measured to be 0.39 mm/year in the cephalocaudal direction and 0.45 mm/year in the mediolateral direction, together averaging 0.42 mm/year. Increases in growth rate additionally did not appear to impact the likelihood of developing conditions including nasal polyposis or chronic sinusitis and symptoms such as sinus pressure, headache, postnasal drip, or congestion. Those with interval scans >36 months were found to have a slower growth rate than those with closer interval scans. Furthermore, former smokers and current smokers had significantly greater growth rates than nonsmokers. CONCLUSION: Given their slow growth rate, we conclude that select lesions likely do not require follow-up. If there is concern that growth could cause an obstructive complication, such as blocking the frontal outflow tract, we argue a single scan at one year is appropriate. If there is additional growth on this scan, surveillance scans up to 3 years could be performed to assess stability. Lastly, while there was a significant growth rate for smokers compared to non-smokers, the slow growth rate is unlikely to influence management.

12.
Am J Otolaryngol ; 45(1): 104074, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37865986

RESUMEN

IMPORTANCE: While there has been an increased understanding of the impact of visible neck scars in some patients with certain diseases, this has not yet been explored in the HPV+ OPSCC population. OBJECTIVE: To understand patients' perception of their scar and the impact on their quality of life (QOL) at least 6 months after neck dissection (ND) for HPV+ oropharyngeal squamous cell carcinoma (OPSCC). DESIGN, SETTING, AND PARTICIPANTS: In this retrospective case-control study, patients who underwent primary transoral robotic surgery (TORS) and ND for HPV+ OPSCC between 2016 and 2021 at a single tertiary care center were identified. Data analysis was performed in January 2022. MAIN OUTCOMES AND MEASURES: Dermatology Life Quality Index was modified (mDLQI) to assess patients' perceptions of their scars. The primary outcome was the mean mDLQI survey score with higher scores corresponding to worse perceptions. Three questions adapted from the Self-Consciousness Scale (SCS) were also included to assess awareness of appearance. All questions were scaled on a 0-3 Likert Scale. Tweedie generalized linear model was used to understand the relationship between mDLQI score and patient- and procedure-specific factors (including the three SCS survey questions). An additional exploratory logistic regression was performed to understand the risk factors for clinically significant mDLQI score change. RESULTS: A total of 67 patients (response rate 57 %) completed the survey with a mean mDLQI survey score of 0.84 (max 30). Although there was a statistically significant negative association between private insurance and mDLQI survey score (95 % Confidence Interval [CI]: -2.72 - -0.38), and a positive association between the SCS score and mDLQI survey score (95 % CI: 0.23-0.81) (p < 0.05), these variables were not found to be risk factors for a clinically significant difference in mDLQI on multivariable analysis. CONCLUSION: The majority of patients felt their neck scars did not interfere with their daily lives. Patient perceptions of neck scars were consistent despite differing patient characteristics and treatment regimens.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias Orofaríngeas , Infecciones por Papillomavirus , Procedimientos Quirúrgicos Robotizados , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/cirugía , Carcinoma de Células Escamosas de Cabeza y Cuello/etiología , Disección del Cuello/efectos adversos , Calidad de Vida , Cicatriz/etiología , Carcinoma de Células Escamosas/patología , Estudios Retrospectivos , Estudios de Casos y Controles , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/cirugía , Neoplasias Orofaríngeas/patología , Neoplasias de Cabeza y Cuello/cirugía , Percepción , Procedimientos Quirúrgicos Robotizados/efectos adversos
13.
J Strength Cond Res ; 38(7): e359-e365, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38662930

RESUMEN

ABSTRACT: Redinger, AL, Russell, JL, Allen, SMF, and Baker, BS. Height restrictions for dual-energy X-ray absorptiometry: what are our options for body composition and bone health precision? J Strength Cond Res 38(7): e359-e365, 2024-Dual-energy X-ray absorptiometry (DXA) is commonly used for testing athlete's body composition, but many athletes are too tall. The first aim was to assess the viability of combining upper- and lower-body regions of interest (ROI), creating a combined scan for tall athletes who do not fit on the table and second, to provide practical solutions to DXA users who routinely scan tall athletes. Sixty subjects (34.8 ± 11.9 years; 171 ± 9 cm) completed 2 total-body DXA scans for baseline precision testing, using GE Lunar Prodigy (LP) or Hologic Horizon A (HA) models. Next, an upper body ROI from the skull to the distal femoral condyles was combined with a flipped scan (feet-to-head) ROI encompassing the proximal tibial plateau to the distal foot. Soft and bone tissue coefficient of variance (CV%) were calculated between the baseline scans and for the newly combined ROI scan. The combined ROI scan added 0.25-0.63% and 0.01-4.35% error rates for the LP and HA, respectively. An exploratory assessment of a GE Lunar iDXA demonstrated results similar to the HA with 4%+ error. The combined ROI scan is a user-friendly and precise method for older LP systems adding less than 1% error; however, newer DXA systems cannot use the stitched scan technique. Coaches and practitioners who use newer DXAs must prioritize consistently using the same boney landmarks (head, jaw, or feet) and ROI heights to provide precise longitudinal assessments of tall athletes' bone and body composition, until larger DXA tables become available.


Asunto(s)
Absorciometría de Fotón , Composición Corporal , Estatura , Densidad Ósea , Humanos , Masculino , Adulto , Composición Corporal/fisiología , Femenino , Densidad Ósea/fisiología , Atletas , Persona de Mediana Edad , Adulto Joven
14.
J Biol Chem ; 298(7): 102073, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35643313

RESUMEN

Deoxynucleoside triphosphate (dNTP) triphosphohydrolases (dNTPases) are important enzymes that may perform multiple functions in the cell, including regulating the dNTP pools and contributing to innate immunity against viruses. Among the homologs that are best studied are human sterile alpha motif and HD domain-containing protein 1 (SAMHD1), a tetrameric dNTPase, and the hexameric Escherichia coli dGTPase; however, it is unclear whether these are representative of all dNTPases given their wide distribution throughout life. Here, we investigated a hexameric homolog from the marine bacterium Leeuwenhoekiella blandensis, revealing that it is a dGTPase that is subject to allosteric activation by dATP, specifically. Allosteric regulation mediated solely by dATP represents a novel regulatory feature among dNTPases that may facilitate maintenance of cellular dNTP pools in L. blandensis. We present high-resolution X-ray crystallographic structures (1.80-2.26 Å) in catalytically important conformations as well as cryo-EM structures (2.1-2.7 Å) of the enzyme bound to dGTP and dATP ligands. The structures, the highest resolution cryo-EM structures of any SAMHD1-like dNTPase to date, reveal an intact metal-binding site with the dGTP substrate coordinated to three metal ions. These structural and biochemical data yield insights into the catalytic mechanism and support a conserved catalytic mechanism for the tetrameric and hexameric dNTPase homologs. We conclude that the allosteric activation by dATP appears to rely on structural connectivity between the allosteric and active sites, as opposed to the changes in oligomeric state upon ligand binding used by SAMHD1.


Asunto(s)
Proteínas de Unión al GTP Monoméricas , Regulación Alostérica/fisiología , Escherichia coli/metabolismo , Flavobacteriaceae , Humanos , Modelos Moleculares , Proteínas de Unión al GTP Monoméricas/metabolismo , Proteína 1 que Contiene Dominios SAM y HD/metabolismo
15.
Environ Sci Technol ; 57(9): 3817-3824, 2023 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-36802589

RESUMEN

People of color disproportionately bear the health impacts of air pollution, making air quality a critical environmental justice issue. However, quantitative analysis of the disproportionate impacts of emissions is rarely done due to a lack of suitable models. Our work develops a high-resolution reduced-complexity model (EASIUR-HR) to evaluate the disproportionate impacts of ground-level primary PM2.5 emissions. Our approach combines a Gaussian plume model for near-source impacts of primary PM2.5 with a previously developed reduced-complexity model, EASIUR, to predict primary PM2.5 concentrations at a spatial resolution of 300 m across the contiguous United States. We find that low-resolution models underpredict important local spatial variation of air pollution exposure to primary PM2.5 emissions, potentially underestimating the contribution of these emissions to national inequality in PM2.5 exposure by more than a factor of 2. We apply EASIUR-HR to analyze the impacts of vehicle electrification on exposure disparities. While such a policy has small aggregate air quality impacts nationally, it reduces exposure disparity for race/ethnic minorities. Our high-resolution RCM for primary PM2.5 emissions (EASIUR-HR) is a new, publicly available tool to assess inequality in air pollution exposure across the United States.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Humanos , Estados Unidos , Material Particulado/análisis , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis
16.
Proc Natl Acad Sci U S A ; 117(36): 22157-22166, 2020 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-32855298

RESUMEN

Subpopulations of ribosomes are responsible for fine tuning the control of protein synthesis in dynamic environments. K63 ubiquitination of ribosomes has emerged as a new posttranslational modification that regulates protein synthesis during cellular response to oxidative stress. K63 ubiquitin, a type of ubiquitin chain that functions independently of the proteasome, modifies several sites at the surface of the ribosome, however, we lack a molecular understanding on how this modification affects ribosome structure and function. Using cryoelectron microscopy (cryo-EM), we resolved the first three-dimensional (3D) structures of K63 ubiquitinated ribosomes from oxidatively stressed yeast cells at 3.5-3.2 Å resolution. We found that K63 ubiquitinated ribosomes are also present in a polysome arrangement, similar to that observed in yeast polysomes, which we determined using cryoelectron tomography (cryo-ET). We further showed that K63 ubiquitinated ribosomes are captured uniquely at the rotated pretranslocation stage of translation elongation. In contrast, cryo-EM structures of ribosomes from mutant cells lacking K63 ubiquitin resolved at 4.4-2.7 Å showed 80S ribosomes represented in multiple states of translation, suggesting that K63 ubiquitin regulates protein synthesis at a selective stage of elongation. Among the observed structural changes, ubiquitin mediates the destabilization of proteins in the 60S P-stalk and in the 40S beak, two binding regions of the eukaryotic elongation factor eEF2. These changes would impact eEF2 function, thus, inhibiting translocation. Our findings help uncover the molecular effects of K63 ubiquitination on ribosomes, providing a model of translation control during oxidative stress, which supports elongation halt at pretranslocation.


Asunto(s)
Estrés Oxidativo , Ribosomas/química , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Microscopía por Crioelectrón , Regulación Fúngica de la Expresión Génica , Modelos Moleculares , Mutación
17.
Am J Otolaryngol ; 44(2): 103782, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36628909

RESUMEN

OBJECTIVE: The laryngeal force sensor (LFS) measures force during suspension microlaryngoscopy (SML) procedures, and has been previously shown to predict postoperative complications. Reproducibility of its measurements has not been described. STUDY DESIGN: Prospective cohort study. SETTING: Academic medical center. METHODS: 291 adult patients had force data collected from 2017 to 2021 during various SML procedures. 94 patients had passive LFS monitoring (surgeon blinded to intraoperative recordings) and 197 had active LFS monitoring (surgeon able to see LFS recordings). 27 of these patients had repeat procedures, with unique LFS metrics for each procedure. The 27 patients were divided into three groups. Group 1 had passive use for both procedures, group 2 had passive use for the first procedure and active use for the second, and group 3 had active use for both procedures. Force metrics from the two procedures were compared with a paired samples t-test. RESULTS: For airway dilation procedures and cancer resection procedures, average force variances were significantly lower with active versus passive use of the LFS. Group 1-no significant changes in maximum force (procedure 1 = 163.8 N, procedure 2 = 133.8 N, p = 0.324) or average force (procedure 1 = 93.6 N, procedure 2 = 78.3 N, p = 0.617). Group 2-maximum force dropped by 35 % between procedures 1 (219.2 N) and 2 (142.5 N), p = 0.013. Average force dropped by 42.5 % between procedures 1 (147.2 N) and 2 (84.6 N), p = 0.007. Group 3-no significant changes in maximum force (procedure 1 = 158.6 N, procedure 2 = 158.2 N, p = 0.986) or average force (procedure 1 = 94.2, procedure 2 = 81.8, p = 0.419). CONCLUSIONS: LFS measurements were reproducible for similar procedures in the same patient when the type of LFS monitoring was not a confounder.


Asunto(s)
Laringe , Adulto , Humanos , Estudios Prospectivos , Reproducibilidad de los Resultados , Laringe/cirugía , Laringoscopía/métodos , Complicaciones Posoperatorias/cirugía
18.
Harm Reduct J ; 20(1): 177, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38057789

RESUMEN

BACKGROUND: Harm reduction strategies can decrease morbidity and mortality associated with substance use. Various barriers limit conversation around substance use between clinicians and patients. Graphic medicine techniques can inform and encourage patient-centered conversations about substance use. We describe the co-development of a harm reduction-focused graphic medicine comic that depicts the infectious risks associated with injection drug use and patient-centered approaches to providing education about potential risk mitigation strategies. METHODS: We formed a co-design group of veterans with lived experience with substance use, physicians, health services researchers, and community-based harm reduction leaders. Over the course of ten sessions, the co-design team developed a storyline and key messages, reviewed draft content and worked with a graphic designer to develop a comic incorporating the veterans' input. During each session, co-design leads presented drafts of the comic and invited feedback from the group. The comic was edited and adapted via this iterative process. RESULTS: The comic depicts a fictionalized clinical vignette in which a patient develops an injection-related abscess and presents to their primary care provider. The dialogue highlights key healthcare principles, including patient autonomy and agency, and highlights strategies for safer use, rather than emphasizing abstinence. Feedback from co-design group participants highlights lessons learned during the development process. DISCUSSION: Graphic medicine is ideally suited for a patient-centered curriculum about harm reduction. This project is one of several interventions that will be integrated into VA facilities nationally to support incorporation of harm reduction principles into the care of persons who inject drugs.


Asunto(s)
Consumidores de Drogas , Abuso de Sustancias por Vía Intravenosa , Trastornos Relacionados con Sustancias , Veteranos , Humanos , Reducción del Daño , Abuso de Sustancias por Vía Intravenosa/complicaciones , Trastornos Relacionados con Sustancias/terapia , Trastornos Relacionados con Sustancias/complicaciones
19.
J Sports Sci ; 41(17): 1587-1595, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38126323

RESUMEN

Military personnel experience elevated bone injury incidence, partly due to arduous and repetitive training. Non-traditional High-Intensity Interval Training-style (HIIT) may benefit pre-enlisted Reserve Officer Training Corps (ROTC) cadet's musculoskeletal health and performance prior to military service. This study investigated 16 ROTC (n = 12 males; n = 4 females) and 15 physically active sex-, age-, and body mass-matched Controls' musculoskeletal health and performance from November to April. Total body, lumbar spine, and dual- hip dual-energy X-ray absorptiometry scans and 4%, 38%, 66% tibial peripheral quantitative computed tomography scans, blood draws (serum sclerostin and parathyroid hormone), and maximal muscle strength and aerobic capacity testing were completed. From November to April, ROTC improved bone density (DXA) of the dominant total hip and greater trochanter and non-dominant greater trochanter and 38% and 66% tibial total volumetric and cortical bone density (pQCT) similarly or more than Controls (all p ≤ 0.049). From November to April, ROTC also improved bench and leg press, and peak aerobic capacity (all p ≤ 0.013). From November to January, serum sclerostin increased (p ≤ 0.007) and remained elevated through April, while parathyroid hormone was unchanged. HIIT-style training induced positive musculoskeletal adaptations, suggesting it may be an excellent pre-service training modality for this injury prone group.


Asunto(s)
Entrenamiento de Intervalos de Alta Intensidad , Masculino , Femenino , Humanos , Huesos , Densidad Ósea/fisiología , Vértebras Lumbares/diagnóstico por imagen , Hormona Paratiroidea
20.
J Emerg Med ; 64(4): 506-512, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36990854

RESUMEN

BACKGROUND: In March 2020, the U.S. Department of Health and Human Services Office for Civil Rights stated that they would use discretion when enforcing the Health Insurance Portability and Accountability Act regarding remote communication technologies that promoted telehealth delivery during the COVID-19 pandemic. This was in an effort to protect patients, clinicians, and staff. More recently, smart speakers-voice-activated, hands-free devices-are being proposed as productivity tools within hospitals. OBJECTIVE: We aimed to characterize the novel use of smart speakers in the emergency department (ED). METHODS: A retrospective observational study of Amazon Echo Show® utilization from May 2020 to October 2020 in a large academic Northeast health system ED. Voice commands and queries were classified as either patient care-related or non-patient care-related, and then further subcategorized to explore the content of given commands. RESULTS: Of 1232 commands analyzed, 200 (16.23%) were determined to be patient care-related. Of these commands, 155 (77.5%) were clinical in nature (i.e., "drop in on triage") and 23 (11.5%) were environment-enhancing commands (i.e., "play calming sounds"). Among non-patient care-related commands, 644 (62.4%) were for entertainment. Among all commands, 804 (65.3%) were during night-shift hours, which was statistically significant (p < 0.001). CONCLUSIONS: Smart speakers showed notable engagement, primarily being used for patient communication and entertainment. Future studies should examine content of patient care conversations using these devices, effects on frontline staff wellbeing, productivity, patient satisfaction, and even explore opportunities for "smart" hospital rooms.


Asunto(s)
COVID-19 , Telemedicina , Humanos , Pandemias , Servicio de Urgencia en Hospital , Estudios Retrospectivos
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