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1.
Cell ; 186(19): 4085-4099.e15, 2023 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-37714134

RESUMEN

Many sequence variants have additive effects on blood lipid levels and, through that, on the risk of coronary artery disease (CAD). We show that variants also have non-additive effects and interact to affect lipid levels as well as affecting variance and correlations. Variance and correlation effects are often signatures of epistasis or gene-environmental interactions. These complex effects can translate into CAD risk. For example, Trp154Ter in FUT2 protects against CAD among subjects with the A1 blood group, whereas it associates with greater risk of CAD in others. His48Arg in ADH1B interacts with alcohol consumption to affect lipid levels and CAD. The effect of variants in TM6SF2 on blood lipids is greatest among those who never eat oily fish but absent from those who often do. This work demonstrates that variants that affect variance of quantitative traits can allow for the discovery of epistasis and interactions of variants with the environment.


Asunto(s)
Enfermedad de la Arteria Coronaria , Animales , Humanos , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/genética , Epistasis Genética , Fenotipo , Lípidos/sangre , Sistema del Grupo Sanguíneo ABO
2.
CA Cancer J Clin ; 72(3): 230-262, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35294043

RESUMEN

The overall 5-year relative survival rate for all cancers combined is now 68%, and there are over 16.9 million survivors in the United States. Evidence from laboratory and observational studies suggests that factors such as diet, physical activity, and obesity may affect risk for recurrence and overall survival after a cancer diagnosis. The purpose of this American Cancer Society guideline is to provide evidence-based, cancer-specific recommendations for anthropometric parameters, physical activity, diet, and alcohol intake for reducing recurrence and cancer-specific and overall mortality. The audiences for this guideline are health care providers caring for cancer survivors as well as cancer survivors and their families. The guideline is intended to serve as a resource for informing American Cancer Society programs, health policy, and the media. Sources of evidence that form the basis of this guideline are systematic literature reviews, meta-analyses, pooled analyses of cohort studies, and large randomized clinical trials published since 2012. Recommendations for nutrition and physical activity during cancer treatment, informed by current practice, large cancer care organizations, and reviews of other expert bodies, are also presented. To provide additional context for the guidelines, the authors also include information on the relationship between health-related behaviors and comorbidities, long-term sequelae and patient-reported outcomes, and health disparities, with attention to enabling survivors' ability to adhere to recommendations. Approaches to meet survivors' needs are addressed as well as clinical care coordination and resources for nutrition and physical activity counseling after a cancer diagnosis.


Asunto(s)
Supervivientes de Cáncer , Neoplasias , American Cancer Society , Dieta , Ejercicio Físico , Humanos , Neoplasias/terapia , Sobrevivientes , Estados Unidos/epidemiología
3.
Cell ; 159(7): 1578-90, 2014 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-25525876

RESUMEN

Proteasomes and lysosomes constitute the major cellular systems that catabolize proteins to recycle free amino acids for energy and new protein synthesis. Tripeptidyl peptidase II (TPPII) is a large cytosolic proteolytic complex that functions in tandem with the proteasome-ubiquitin protein degradation pathway. We found that autosomal recessive TPP2 mutations cause recurrent infections, autoimmunity, and neurodevelopmental delay in humans. We show that a major function of TPPII in mammalian cells is to maintain amino acid levels and that TPPII-deficient cells compensate by increasing lysosome number and proteolytic activity. However, the overabundant lysosomes derange cellular metabolism by consuming the key glycolytic enzyme hexokinase-2 through chaperone-mediated autophagy. This reduces glycolysis and impairs the production of effector cytokines, including IFN-γ and IL-1ß. Thus, TPPII controls the balance between intracellular amino acid availability, lysosome number, and glycolysis, which is vital for adaptive and innate immunity and neurodevelopmental health.


Asunto(s)
Inmunidad Adaptativa , Aminopeptidasas/metabolismo , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/metabolismo , Glucólisis , Inmunidad Innata , Síndromes de Inmunodeficiencia/genética , Síndromes de Inmunodeficiencia/metabolismo , Proteolisis , Serina Endopeptidasas/metabolismo , Secuencia de Aminoácidos , Aminopeptidasas/química , Animales , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/química , Femenino , Humanos , Síndromes de Inmunodeficiencia/inmunología , Lisosomas/metabolismo , Masculino , Modelos Moleculares , Datos de Secuencia Molecular , Linaje , Alineación de Secuencia , Serina Endopeptidasas/química
4.
Mol Cell ; 80(6): 1092-1103.e4, 2020 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-33248025

RESUMEN

The nucleocapsid (N) protein of coronaviruses serves two major functions: compaction of the RNA genome in the virion and regulation of viral gene transcription. It is not clear how the N protein mediates such distinct functions. The N protein contains two RNA-binding domains surrounded by regions of intrinsic disorder. Phosphorylation of the central disordered region promotes the protein's transcriptional function, but the underlying mechanism is not known. Here, we show that the N protein of SARS-CoV-2, together with viral RNA, forms biomolecular condensates. Unmodified N protein forms partially ordered gel-like condensates and discrete 15-nm particles based on multivalent RNA-protein and protein-protein interactions. Phosphorylation reduces these interactions, generating a more liquid-like droplet. We propose that distinct oligomeric states support the two functions of the N protein: unmodified protein forms a structured oligomer that is suited for nucleocapsid assembly, and phosphorylated protein forms a liquid-like compartment for viral genome processing.


Asunto(s)
COVID-19 , Proteínas de la Nucleocápside de Coronavirus/química , Multimerización de Proteína , ARN Viral/química , SARS-CoV-2/química , Proteínas de la Nucleocápside de Coronavirus/genética , Proteínas de la Nucleocápside de Coronavirus/metabolismo , Humanos , Fosfoproteínas/química , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Fosforilación , Dominios Proteicos , ARN Viral/genética , ARN Viral/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/metabolismo
5.
Genome Res ; 34(1): 145-159, 2024 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-38290977

RESUMEN

Hundreds of inbred mouse strains and intercross populations have been used to characterize the function of genetic variants that contribute to disease. Thousands of disease-relevant traits have been characterized in mice and made publicly available. New strains and populations including consomics, the collaborative cross, expanded BXD, and inbred wild-derived strains add to existing complex disease mouse models, mapping populations, and sensitized backgrounds for engineered mutations. The genome sequences of inbred strains, along with dense genotypes from others, enable integrated analysis of trait-variant associations across populations, but these analyses are hampered by the sparsity of genotypes available. Moreover, the data are not readily interoperable with other resources. To address these limitations, we created a uniformly dense variant resource by harmonizing multiple data sets. Missing genotypes were imputed using the Viterbi algorithm with a data-driven technique that incorporates local phylogenetic information, an approach that is extendable to other model organisms. The result is a web- and programmatically accessible data service called GenomeMUSter, comprising single-nucleotide variants covering 657 strains at 106.8 million segregating sites. Interoperation with phenotype databases, analytic tools, and other resources enable a wealth of applications, including multitrait, multipopulation meta-analysis. We show this in cross-species comparisons of type 2 diabetes and substance use disorder meta-analyses, leveraging mouse data to characterize the likely role of human variant effects in disease. Other applications include refinement of mapped loci and prioritization of strain backgrounds for disease modeling to further unlock extant mouse diversity for genetic and genomic studies in health and disease.


Asunto(s)
Diabetes Mellitus Tipo 2 , Humanos , Ratones , Animales , Filogenia , Genotipo , Ratones Endogámicos , Fenotipo , Mutación , Variación Genética
6.
Nature ; 596(7870): 138-142, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34290405

RESUMEN

In early mitosis, the duplicated chromosomes are held together by the ring-shaped cohesin complex1. Separation of chromosomes during anaphase is triggered by separase-a large cysteine endopeptidase that cleaves the cohesin subunit SCC1 (also known as RAD212-4). Separase is activated by degradation of its inhibitors, securin5 and cyclin B6, but the molecular mechanisms of separase regulation are not clear. Here we used cryogenic electron microscopy to determine the structures of human separase in complex with either securin or CDK1-cyclin B1-CKS1. In both complexes, separase is inhibited by pseudosubstrate motifs that block substrate binding at the catalytic site and at nearby docking sites. As in Caenorhabditis elegans7 and yeast8, human securin contains its own pseudosubstrate motifs. By contrast, CDK1-cyclin B1 inhibits separase by deploying pseudosubstrate motifs from intrinsically disordered loops in separase itself. One autoinhibitory loop is oriented by CDK1-cyclin B1 to block the catalytic sites of both separase and CDK19,10. Another autoinhibitory loop blocks substrate docking in a cleft adjacent to the separase catalytic site. A third separase loop contains a phosphoserine6 that promotes complex assembly by binding to a conserved phosphate-binding pocket in cyclin B1. Our study reveals the diverse array of mechanisms by which securin and CDK1-cyclin B1 bind and inhibit separase, providing the molecular basis for the robust control of chromosome segregation.


Asunto(s)
Proteína Quinasa CDC2/química , Proteína Quinasa CDC2/metabolismo , Ciclina B1/química , Ciclina B1/metabolismo , Securina/química , Securina/metabolismo , Separasa/química , Separasa/metabolismo , Secuencias de Aminoácidos , Proteína Quinasa CDC2/antagonistas & inhibidores , Proteína Quinasa CDC2/ultraestructura , Quinasas CDC2-CDC28/química , Quinasas CDC2-CDC28/metabolismo , Quinasas CDC2-CDC28/ultraestructura , Proteínas de Ciclo Celular/metabolismo , Segregación Cromosómica , Microscopía por Crioelectrón , Ciclina B1/ultraestructura , Proteínas de Unión al ADN/metabolismo , Humanos , Modelos Moleculares , Fosfoserina/metabolismo , Unión Proteica , Dominios Proteicos , Securina/ultraestructura , Separasa/antagonistas & inhibidores , Separasa/ultraestructura , Especificidad por Sustrato
7.
Hum Mol Genet ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38888340

RESUMEN

The MRE11/RAD50/NBS1 (MRN) complex plays critical roles in cellular responses to DNA double-strand breaks. MRN is involved in end binding and processing, and it also induces cell cycle checkpoints by activating the ataxia-telangiectasia mutated (ATM) protein kinase. Hypomorphic pathogenic variants in the MRE11, RAD50, or NBS1 genes cause autosomal recessive genome instability syndromes featuring variable degrees of dwarfism, neurological defects, anemia, and cancer predisposition. Disease-associated MRN alleles include missense and nonsense variants, and many cause reduced protein levels of the entire MRN complex. However, the dramatic variability in the disease manifestation of MRN pathogenic variants is not understood. We sought to determine if low protein levels are a significant contributor to disease sequelae and therefore generated a transgenic murine model expressing MRE11 at low levels. These mice display dramatic phenotypes including small body size, severe anemia, and impaired DNA repair. We demonstrate that, distinct from ataxia telangiectasia-like disorder caused by MRE11 pathogenic missense or nonsense variants, mice and cultured cells expressing low MRE11 levels do not display the anticipated defects in ATM activation. Our findings indicate that ATM signaling can be supported by very low levels of the MRN complex and imply that defective ATM activation results from perturbation of MRN function caused by specific hypomorphic disease mutations. These distinct phenotypic outcomes underline the importance of understanding the impact of specific pathogenic MRE11 variants, which may help direct appropriate early surveillance for patients with these complicated disorders in a clinical setting.

8.
N Engl J Med ; 389(19): 1741-1752, 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37937776

RESUMEN

BACKGROUND: In 2021, the American College of Medical Genetics and Genomics (ACMG) recommended reporting actionable genotypes in 73 genes associated with diseases for which preventive or therapeutic measures are available. Evaluations of the association of actionable genotypes in these genes with life span are currently lacking. METHODS: We assessed the prevalence of coding and splice variants in genes on the ACMG Secondary Findings, version 3.0 (ACMG SF v3.0), list in the genomes of 57,933 Icelanders. We assigned pathogenicity to all reviewed variants using reported evidence in the ClinVar database, the frequency of variants, and their associations with disease to create a manually curated set of actionable genotypes (variants). We assessed the relationship between these genotypes and life span and further examined the specific causes of death among carriers. RESULTS: Through manual curation of 4405 sequence variants in the ACMG SF v3.0 genes, we identified 235 actionable genotypes in 53 genes. Of the 57,933 participants, 2306 (4.0%) carried at least one actionable genotype. We found shorter median survival among persons carrying actionable genotypes than among noncarriers. Specifically, we found that carrying an actionable genotype in a cancer gene was associated with survival that was 3 years shorter than that among noncarriers, with causes of death among carriers attributed primarily to cancer-related conditions. Furthermore, we found evidence of association between carrying an actionable genotype in certain genes in the cardiovascular disease group and a reduced life span. CONCLUSIONS: On the basis of the ACMG SF v3.0 guidelines, we found that approximately 1 in 25 Icelanders carried an actionable genotype and that carrying such a genotype was associated with a reduced life span. (Funded by deCODE Genetics-Amgen.).


Asunto(s)
Enfermedad , Genómica , Longevidad , Humanos , Alelos , Pruebas Genéticas , Variación Genética , Genotipo , Islandia/epidemiología , Longevidad/genética , Enfermedad/genética , Enfermedades Cardiovasculares/genética , Neoplasias/genética
9.
Proc Natl Acad Sci U S A ; 120(34): e2209735120, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37579162

RESUMEN

The hydroxyl radical (OH) fuels atmospheric chemical cycling as the main sink for methane and a driver of the formation and loss of many air pollutants, but direct OH observations are sparse. We develop and evaluate an observation-based proxy for short-term, spatial variations in OH (ProxyOH) in the remote marine troposphere using comprehensive measurements from the NASA Atmospheric Tomography (ATom) airborne campaign. ProxyOH is a reduced form of the OH steady-state equation representing the dominant OH production and loss pathways in the remote marine troposphere, according to box model simulations of OH constrained with ATom observations. ProxyOH comprises only eight variables that are generally observed by routine ground- or satellite-based instruments. ProxyOH scales linearly with in situ [OH] spatial variations along the ATom flight tracks (median r2 = 0.90, interquartile range = 0.80 to 0.94 across 2-km altitude by 20° latitudinal regions). We deconstruct spatial variations in ProxyOH as a first-order approximation of the sensitivity of OH variations to individual terms. Two terms modulate within-region ProxyOH variations-water vapor (H2O) and, to a lesser extent, nitric oxide (NO). This implies that a limited set of observations could offer an avenue for observation-based mapping of OH spatial variations over much of the remote marine troposphere. Both H2O and NO are expected to change with climate, while NO also varies strongly with human activities. We also illustrate the utility of ProxyOH as a process-based approach for evaluating intermodel differences in remote marine tropospheric OH.

10.
Cell ; 141(2): 224-6, 2010 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-20403319

RESUMEN

The cell divides in a series of discrete steps that occur in a specific order. Lu and Cross (2010) now propose that cell-cycle events are ordered by a regulatory system in which a master oscillator, based on cyclin-dependent kinases, entrains a series of peripheral oscillators controlling individual events.

11.
Nucleic Acids Res ; 51(D1): D1067-D1074, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36330959

RESUMEN

The Mouse Phenome Database (MPD; https://phenome.jax.org; RRID:SCR_003212), supported by the US National Institutes of Health, is a Biomedical Data Repository listed in the Trans-NIH Biomedical Informatics Coordinating Committee registry. As an increasingly FAIR-compliant and TRUST-worthy data repository, MPD accepts phenotype and genotype data from mouse experiments and curates, organizes, integrates, archives, and distributes those data using community standards. Data are accompanied by rich metadata, including widely used ontologies and detailed protocols. Data are from all over the world and represent genetic, behavioral, morphological, and physiological disease-related characteristics in mice at baseline or those exposed to drugs or other treatments. MPD houses data from over 6000 strains and populations, representing many reproducible strain types and heterogenous populations such as the Diversity Outbred where each mouse is unique but can be genotyped throughout the genome. A suite of analysis tools is available to aggregate, visualize, and analyze these data within and across studies and populations in an increasingly traceable and reproducible manner. We have refined existing resources and developed new tools to continue to provide users with access to consistent, high-quality data that has translational relevance in a modernized infrastructure that enables interaction with a suite of bioinformatics analytic and data services.


Asunto(s)
Bases de Datos Genéticas , Fenómica , Ratones , Animales , Ratones Endogámicos , Fenotipo , Genotipo
12.
Proc Natl Acad Sci U S A ; 119(37): e2201213119, 2022 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-36067322

RESUMEN

Atmospheric electrical discharges are now known to generate unexpectedly large amounts of the atmosphere's primary oxidant, hydroxyl (OH), in thunderstorm anvils, where electrical discharges are caused by atmospheric charge separation. The question is "Do other electrical discharges also generate large amounts of oxidants?" In this paper, we demonstrate that corona formed on grounded metal objects under thunderstorms produce extreme amounts of OH, hydroperoxyl (HO2), and ozone (O3). Hundreds of parts per trillion to parts per billion of OH and HO2 were measured during seven thunderstorms that passed over the rooftop site during an air quality study in Houston, TX in summer 2006. A combination of analysis of these field results and laboratory experiments shows that these extreme oxidant amounts were generated by corona on the inlet of the OH-measuring instrument and that corona are easier to generate on lightning rods than on the inlet. In the laboratory, increasing the electric field increased OH, HO2, and O3, with 14 times more O3 generated than OH and HO2, which were equal. Calculations show that corona on lightning rods can annually generate OH that is 10-100 times ambient amounts within centimeters of the lightning rod and on high-voltage electrical power lines can generate OH that is 500 times ambient a meter away from the corona. Contrary to current thinking, previously unrecognized corona-generated OH, not corona-generated UV radiation, mostly likely initiates premature degradation of high-voltage polymer insulators.

13.
Pharmacol Rev ; 74(4): 1136-1145, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36180110

RESUMEN

The number of cancer drugs is increasing as new chemical entities are developed to target molecules, often protein kinases, driving cancer progression. In 2009, Fedorov et al. identified that of the protein kinases in the human kinome, most of the focus has been on a small subset. They highlighted that many poorly investigated protein kinases were cancer drivers, but there was no relationship between publications and involvement in cancer development or progression. Since 2009, there has been a doubling in the number of publications, patents, and drugs targeting the kinome. To determine whether this was an expansion in knowledge of well-studied targets-searching in the light under the lamppost-or an explosion of investigations into previously poorly investigated targets, we searched the literature for publications on each kinase, updating Federov et al.'s assessment of the druggable kinome. The proportion of papers focusing on the 50 most-studied kinases had not changed, and the makeup of those 50 had barely changed. The majority of new drugs (80%) were against the same group of 50 kinases identified as targets 10 years ago, and the proportion of studies investigating previously poorly investigated kinases (<1%) was unchanged. With three exceptions [p38 mitogenactivated protein kinase (p38a), AMP-activated protein kinase catalytic α-subunit 1,2, and B-Raf proto-oncogene (BRAF) serine/threonine kinase], >95% of publications addressing kinases still focused on a relatively small proportion (<50%) of the human kinome independently of their involvement as cancer drivers. There is, therefore, still extensive scope for discovery of therapeutics targeting different protein kinases in cancer and still a bias toward well-characterized targets over the innovative searchlight into the unknown. SIGNIFICANCE STATEMENT: This study presents evidence that drug discovery efforts in cancer are still to some extent focused on a narrow group of well-studied kinases 10 years after the identification of multiple novel cancer targets in the human kinome. This suggests that there is still room for researchers in academia, industry, and the not-for-profit sector to develop new and diverse therapies targeting kinases for cancer.


Asunto(s)
Antineoplásicos , Neoplasias , Proteínas Quinasas Activadas por AMP , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Humanos , Neoplasias/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Serina-Treonina Quinasas , Proteínas Proto-Oncogénicas B-raf , Serina
14.
Nano Lett ; 24(26): 8080-8088, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38888232

RESUMEN

Among various mRNA carrier systems, lipid nanoparticles (LNPs) stand out as the most clinically advanced. While current clinical trials of mRNA/LNP therapeutics mainly address liver diseases, the potential of mRNA therapy extends far beyond─yet to be unraveled. To fully unlock the promises of mRNA therapy, there is an urgent need to develop safe and effective LNP systems that can target extrahepatic organs. Here, we report on the development of sulfonium lipid nanoparticles (sLNPs) for systemic mRNA delivery to the lungs. sLNP effectively and specifically delivered mRNA to the lungs following intravenous administration in mice. No evidence of lung and systemic inflammation or toxicity in major organs was induced by sLNP. Our findings demonstrated that the newly developed lung-specific sLNP platform is both safe and efficacious. It holds great promise for advancing the development of new mRNA-based therapies for the treatment of lung-associated diseases and conditions.


Asunto(s)
Lípidos , Pulmón , Nanopartículas , ARN Mensajero , Animales , Pulmón/metabolismo , Nanopartículas/química , Ratones , ARN Mensajero/genética , ARN Mensajero/administración & dosificación , Lípidos/química , Humanos , Compuestos de Sulfonio/química , Técnicas de Transferencia de Gen , Liposomas
15.
J Biol Chem ; 299(12): 105362, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37863261

RESUMEN

The nucleocapsid (N) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) compacts the RNA genome into viral ribonucleoprotein (vRNP) complexes within virions. Assembly of vRNPs is inhibited by phosphorylation of the N protein serine/arginine (SR) region. Several SARS-CoV-2 variants of concern carry N protein mutations that reduce phosphorylation and enhance the efficiency of viral packaging. Variants of the dominant B.1.1 viral lineage also encode a truncated N protein, termed N∗ or Δ(1-209), that mediates genome packaging despite lacking the N-terminal RNA-binding domain and SR region. Here, we use mass photometry and negative stain electron microscopy to show that purified Δ(1-209) and viral RNA assemble into vRNPs that are remarkably similar in size and shape to those formed with full-length N protein. We show that assembly of Δ(1-209) vRNPs requires the leucine-rich helix of the central disordered region and that this helix promotes N protein oligomerization. We also find that fusion of a phosphomimetic SR region to Δ(1-209) inhibits RNA binding and vRNP assembly. Our results provide new insights into the mechanisms by which RNA binding promotes N protein self-association and vRNP assembly, and how this process is modulated by phosphorylation.


Asunto(s)
Proteínas de la Nucleocápside , SARS-CoV-2 , Humanos , COVID-19/virología , Proteínas de la Nucleocápside/genética , Proteínas de la Nucleocápside/metabolismo , Proteínas de la Nucleocápside/ultraestructura , ARN Viral/metabolismo , ARN Viral/ultraestructura , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , SARS-CoV-2/ultraestructura , Fosforilación , Ensamble de Virus/genética
16.
J Am Chem Soc ; 146(26): 17679-17690, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38889404

RESUMEN

The complex interrelationships among thermoelectric parameters mean that a priori design of high-performing materials is difficult. However, band engineering can allow the power factor to be optimized through enhancement of the Seebeck coefficient. Herein, using layered Sb2Si2Te6 and Sc2Si2Te6 as model systems, we comprehensively investigate and compare their thermoelectric properties by employing density functional theory combined with semiclassical Boltzmann transport theory. Our simulations reveal that Sb2Si2Te6 exhibits superior electrical conductivity compared to Sc2Si2Te6 due to lower scattering rates and more pronounced band dispersion. Remarkably, despite Sb2Si2Te6 exhibiting a lower lattice thermal conductivity and superior electrical conductivity, Sc2Si2Te6 is predicted to achieve an extraordinary dimensionless figure of merit (ZT) of 3.51 at 1000 K, which significantly surpasses the predicted maximum ZT of 2.76 for Sb2Si2Te6 at 900 K. We find the origin of this behavior to be a combined increase in band (valley) degeneracy and anisotropy upon switching the conduction band orbital character from Sb p to Sc d, yielding a significantly improved Seebeck coefficient. This work suggests that enhancing band degeneracy and anisotropy (complexity) through compositional variation is an effective strategy for improving the thermoelectric performance of layered materials.

17.
Ann Surg ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38916098

RESUMEN

OBJECTIVE: We sought to determine the premium associated with a career in academic surgery, as measured by compensation normalized to the work relative value unit (wRVU). BACKGROUND: An academic surgical career, embodying innovation and mentorship, offers intrinsic rewards, but is not well monetized. We know compensation for academic surgeons is less than their non-academic counterparts, but the value of clinical effort, as normalized to the wRVU, between academic and non-academic surgeons has not been well characterized. Thus, we analyzed the variations in the valuation of academic and non-academic surgical work from 2010 to 2022. METHODS: We utilized Medical Group Management Association Provider Compensation data from 2010, 2014, 2018, and 2022 to compare academic and non-academic surgeons. We analyzed raw total cash compensation (TCC), wRVU, TCC per wRVU (TCC/wRVU), and TCC to collections (TCCtColl). We calculated collections per wRVU (Coll/wRVU). We adjusted TCC and TCCtColl for inflation using the Consumer Price Index. Linear modeling for trend analysis was performed. RESULTS: Compared to non-academic, academic surgeons had lower TCC (2010: $500,415.0±23,666 vs. $631,515.5±23,948.2, -21%; 2022: $564,789.8±23,993.9 vs. $628,247.4±15,753.2, -10%), despite higher wRVUs (2022: 9,109.4±474.9 vs. 8,062.7±252.7) and higher Coll/wRVU (2022: 76.68±8.15 vs. 71.80±6.10). Trend analysis indicated TCC will converge in 2038 at an estimated $660,931. CONCLUSIONS: In 2022, academic surgeons had more clinical activity and superior organizational revenue capture, despite less total and normalized clinical compensation. Based on TCC/wRVUs, academia charges a premium of 16% over non-academic surgery. However, trend analysis suggests that TCC will converge within the next twenty years.

18.
N Engl J Med ; 384(11): 1015-1027, 2021 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-33523609

RESUMEN

BACKGROUND: Convalescent plasma has been widely used to treat coronavirus disease 2019 (Covid-19) under the presumption that such plasma contains potentially therapeutic antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that can be passively transferred to the plasma recipient. Whether convalescent plasma with high antibody levels rather than low antibody levels is associated with a lower risk of death is unknown. METHODS: In a retrospective study based on a U.S. national registry, we determined the anti-SARS-CoV-2 IgG antibody levels in convalescent plasma used to treat hospitalized adults with Covid-19. The primary outcome was death within 30 days after plasma transfusion. Patients who were enrolled through July 4, 2020, and for whom data on anti-SARS-CoV-2 antibody levels in plasma transfusions and on 30-day mortality were available were included in the analysis. RESULTS: Of the 3082 patients included in this analysis, death within 30 days after plasma transfusion occurred in 115 of 515 patients (22.3%) in the high-titer group, 549 of 2006 patients (27.4%) in the medium-titer group, and 166 of 561 patients (29.6%) in the low-titer group. The association of anti-SARS-CoV-2 antibody levels with the risk of death from Covid-19 was moderated by mechanical ventilation status. A lower risk of death within 30 days in the high-titer group than in the low-titer group was observed among patients who had not received mechanical ventilation before transfusion (relative risk, 0.66; 95% confidence interval [CI], 0.48 to 0.91), and no effect on the risk of death was observed among patients who had received mechanical ventilation (relative risk, 1.02; 95% CI, 0.78 to 1.32). CONCLUSIONS: Among patients hospitalized with Covid-19 who were not receiving mechanical ventilation, transfusion of plasma with higher anti-SARS-CoV-2 IgG antibody levels was associated with a lower risk of death than transfusion of plasma with lower antibody levels. (Funded by the Department of Health and Human Services and others; ClinicalTrials.gov number, NCT04338360.).


Asunto(s)
Anticuerpos Antivirales/sangre , COVID-19/terapia , SARS-CoV-2/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/inmunología , COVID-19/mortalidad , Femenino , Hospitalización , Humanos , Inmunización Pasiva , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad , Sistema de Registros , Respiración Artificial , Estudios Retrospectivos , Factores de Riesgo , Tiempo de Tratamiento , Estados Unidos/epidemiología , Adulto Joven , Sueroterapia para COVID-19
19.
Thorax ; 79(4): 307-315, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38195644

RESUMEN

BACKGROUND: Low-dose CT screening can reduce lung cancer-related mortality. However, most screen-detected pulmonary abnormalities do not develop into cancer and it often remains challenging to identify malignant nodules, particularly among indeterminate nodules. We aimed to develop and assess prediction models based on radiological features to discriminate between benign and malignant pulmonary lesions detected on a baseline screen. METHODS: Using four international lung cancer screening studies, we extracted 2060 radiomic features for each of 16 797 nodules (513 malignant) among 6865 participants. After filtering out low-quality radiomic features, 642 radiomic and 9 epidemiological features remained for model development. We used cross-validation and grid search to assess three machine learning (ML) models (eXtreme Gradient Boosted Trees, random forest, least absolute shrinkage and selection operator (LASSO)) for their ability to accurately predict risk of malignancy for pulmonary nodules. We report model performance based on the area under the curve (AUC) and calibration metrics in the held-out test set. RESULTS: The LASSO model yielded the best predictive performance in cross-validation and was fit in the full training set based on optimised hyperparameters. Our radiomics model had a test-set AUC of 0.93 (95% CI 0.90 to 0.96) and outperformed the established Pan-Canadian Early Detection of Lung Cancer model (AUC 0.87, 95% CI 0.85 to 0.89) for nodule assessment. Our model performed well among both solid (AUC 0.93, 95% CI 0.89 to 0.97) and subsolid nodules (AUC 0.91, 95% CI 0.85 to 0.95). CONCLUSIONS: We developed highly accurate ML models based on radiomic and epidemiological features from four international lung cancer screening studies that may be suitable for assessing indeterminate screen-detected pulmonary nodules for risk of malignancy.


Asunto(s)
Neoplasias Pulmonares , Nódulos Pulmonares Múltiples , Humanos , Neoplasias Pulmonares/diagnóstico , Detección Precoz del Cáncer , Radiómica , Tomografía Computarizada por Rayos X , Canadá , Nódulos Pulmonares Múltiples/patología , Aprendizaje Automático , Estudios Retrospectivos
20.
Mol Ecol ; 33(3): e17233, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38063472

RESUMEN

The study of hybrid zones offers important insights into speciation. Earlier studies on hybrid populations of the marine mussel species Mytilus edulis and Mytilus galloprovincialis in SW England provided evidence of admixture but were constrained by the limited number of molecular markers available. We use 57 ancestry-informative SNPs, most of which have been mapped genetically, to provide evidence of distinctive differences between admixed populations in SW England and asymmetrical introgression from M. edulis to M. galloprovincialis. We combine the genetic study with analysis of phenotypic traits of potential ecological and adaptive significance. We demonstrate that hybrid individuals have brown mantle edges unlike the white or purple in the parental species, suggesting allelic or non-allelic genomic interactions. We report differences in gonad development stage between the species consistent with a prezygotic barrier between the species. By incorporating results from publications dating back to 1980, we confirm the long-term stability of the hybrid zone despite higher viability of M. galloprovincialis. This stability coincides with a dramatic change in temperature of UK coastal waters and suggests that these hybrid populations might be resisting the effects of global warming. However, a single SNP locus associated with the Notch transmembrane signalling protein shows a markedly different pattern of variation to the others and might be associated with adaptation of M. galloprovincialis to colder northern temperatures.


Asunto(s)
Mytilus edulis , Mytilus , Humanos , Animales , Mytilus/genética , Mytilus edulis/genética , Polimorfismo de Nucleótido Simple , Genoma , Inglaterra
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