Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 7.077
Filtrar
Mais filtros

Coleções SMS-SP
Intervalo de ano de publicação
1.
CA Cancer J Clin ; 74(4): 368-382, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38517462

RESUMO

Multicancer detection (MCD) tests use a single, easily obtainable biospecimen, such as blood, to screen for more than one cancer concurrently. MCD tests can potentially be used to improve early cancer detection, including cancers that currently lack effective screening methods. However, these tests have unknown and unquantified benefits and harms. MCD tests differ from conventional cancer screening tests in that the organ responsible for a positive test is unknown, and a broad diagnostic workup may be necessary to confirm the location and type of underlying cancer. Among two prospective studies involving greater than 16,000 individuals, MCD tests identified those who had some cancers without currently recommended screening tests, including pancreas, ovary, liver, uterus, small intestine, oropharyngeal, bone, thyroid, and hematologic malignancies, at early stages. Reported MCD test sensitivities range from 27% to 95% but differ by organ and are lower for early stage cancers, for which treatment toxicity would be lowest and the potential for cure might be highest. False reassurance from a negative MCD result may reduce screening adherence, risking a loss in proven public health benefits from standard-of-care screening. Prospective clinical trials are needed to address uncertainties about MCD accuracy to detect different cancers in asymptomatic individuals, whether these tests can detect cancer sufficiently early for effective treatment and mortality reduction, the degree to which these tests may contribute to cancer overdiagnosis and overtreatment, whether MCD tests work equally well across all populations, and the appropriate diagnostic evaluation and follow-up for patients with a positive test.


Assuntos
Detecção Precoce de Câncer , Neoplasias , Humanos , Neoplasias/diagnóstico , Detecção Precoce de Câncer/métodos , Pesquisa Translacional Biomédica , Sensibilidade e Especificidade , Programas de Rastreamento/métodos
2.
Nat Immunol ; 18(3): 255-262, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28198830

RESUMO

Effective clinical cancer immunotherapies, such as administration of the cytokine IL-2, adoptive cell transfer (ACT) and the recent success of blockade of the checkpoint modulators CTLA-4 and PD-1, have been developed without clear identification of the immunogenic targets expressed by human cancers in vivo. Immunotherapy of patients with cancer through the use of ACT with autologous lymphocytes has provided an opportunity to directly investigate the antigen recognition of lymphocytes that mediate cancer regression in humans. High-throughput immunological testing of such lymphocytes in combination with improvements in deep sequencing of the autologous cancer have provided new insight into the molecular characterization and incidence of anti-tumor lymphocytes present in patients with cancer. Here we highlight evidence suggesting that T cells that target tumor neoantigens arising from cancer mutations are the main mediators of many effective cancer immunotherapies in humans.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Vacinas Anticâncer/imunologia , Imunoterapia/métodos , Interleucina-2/uso terapêutico , Neoplasias/terapia , Linfócitos T/transplante , Animais , Antígenos de Neoplasias/imunologia , Antígeno CTLA-4/imunologia , Humanos , Vigilância Imunológica , Imunoterapia/tendências , Neoplasias/imunologia , Receptor de Morte Celular Programada 1/imunologia , Linfócitos T/imunologia
3.
Cell ; 154(3): 637-50, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23911326

RESUMO

Synaptic plasticity induced by cocaine and other drugs underlies addiction. Here we elucidate molecular events at synapses that cause this plasticity and the resulting behavioral response to cocaine in mice. In response to D1-dopamine-receptor signaling that is induced by drug administration, the glutamate-receptor protein metabotropic glutamate receptor 5 (mGluR5) is phosphorylated by microtubule-associated protein kinase (MAPK), which we show potentiates Pin1-mediated prolyl-isomerization of mGluR5 in instances where the product of an activity-dependent gene, Homer1a, is present to enable Pin1-mGluR5 interaction. These biochemical events potentiate N-methyl-D-aspartate receptor (NMDAR)-mediated currents that underlie synaptic plasticity and cocaine-evoked motor sensitization as tested in mice with relevant mutations. The findings elucidate how a coincidence of signals from the nucleus and the synapse can render mGluR5 accessible to activation with consequences for drug-induced dopamine responses and point to depotentiation at corticostriatal synapses as a possible therapeutic target for treating addiction.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/fisiopatologia , Cocaína/metabolismo , Dopamina/metabolismo , Peptidilprolil Isomerase/metabolismo , Sequência de Aminoácidos , Animais , Encéfalo/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Embrião de Mamíferos/metabolismo , Proteínas de Arcabouço Homer , Potenciação de Longa Duração , Camundongos , Dados de Sequência Molecular , Peptidilprolil Isomerase de Interação com NIMA , Fosforilação , Receptores de AMPA/metabolismo , Receptores de Dopamina D1/metabolismo , Receptores de Ácido Caínico/química , Receptores de Ácido Caínico/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapses/metabolismo
4.
Nat Methods ; 21(5): 804-808, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38191935

RESUMO

Neuroimaging research requires purpose-built analysis software, which is challenging to install and may produce different results across computing environments. The community-oriented, open-source Neurodesk platform ( https://www.neurodesk.org/ ) harnesses a comprehensive and growing suite of neuroimaging software containers. Neurodesk includes a browser-accessible virtual desktop, command-line interface and computational notebook compatibility, allowing for accessible, flexible, portable and fully reproducible neuroimaging analysis on personal workstations, high-performance computers and the cloud.


Assuntos
Neuroimagem , Software , Neuroimagem/métodos , Humanos , Interface Usuário-Computador , Reprodutibilidade dos Testes , Encéfalo/diagnóstico por imagem
5.
Cell ; 149(4): 886-98, 2012 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-22579289

RESUMO

The Arc/Arg3.1 gene product is rapidly upregulated by strong synaptic activity and critically contributes to weakening synapses by promoting AMPA-R endocytosis. However, how activity-induced Arc is redistributed and determines the synapses to be weakened remains unclear. Here, we show targeting of Arc to inactive synapses via a high-affinity interaction with CaMKIIß that is not bound to calmodulin. Synaptic Arc accumulates in inactive synapses that previously experienced strong activation and correlates with removal of surface GluA1 from individual synapses. A lack of CaMKIIß either in vitro or in vivo resulted in loss of Arc upregulation in the silenced synapses. The discovery of Arc's role in "inverse" synaptic tagging that is specific for weaker synapses and prevents undesired enhancement of weak synapses in potentiated neurons reconciles essential roles of Arc both for the late phase of long-term plasticity and for reduction of surface AMPA-Rs in stimulated neurons.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteínas do Citoesqueleto/metabolismo , Hipocampo/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Sinapses/metabolismo , Animais , Células Cultivadas , Espinhas Dendríticas/metabolismo , Hipocampo/citologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ratos , Ratos Sprague-Dawley
6.
Mol Cell ; 75(1): 13-25.e5, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31151856

RESUMO

Arc is a synaptic protein essential for memory consolidation. Recent studies indicate that Arc originates in evolution from a Ty3-Gypsy retrotransposon GAG domain. The N-lobe of Arc GAG domain acquired a hydrophobic binding pocket in higher vertebrates that is essential for Arc's canonical function to weaken excitatory synapses. Here, we report that Arc GAG also acquired phosphorylation sites that can acutely regulate its synaptic function. CaMKII phosphorylates the N-lobe of the Arc GAG domain and disrupts an interaction surface essential for high-order oligomerization. In Purkinje neurons, CaMKII phosphorylation acutely reverses Arc's synaptic action. Mutant Arc that cannot be phosphorylated by CaMKII enhances metabotropic receptor-dependent depression in the hippocampus but does not alter baseline synaptic transmission or long-term potentiation. Behavioral studies indicate that hippocampus- and amygdala-dependent learning requires Arc GAG domain phosphorylation. These studies provide an atomic model for dynamic and local control of Arc function underlying synaptic plasticity and memory.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteínas do Citoesqueleto/metabolismo , Potenciação de Longa Duração/fisiologia , Memória/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Células de Purkinje/metabolismo , Sequência de Aminoácidos , Tonsila do Cerebelo/citologia , Tonsila do Cerebelo/metabolismo , Animais , Sítios de Ligação , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/química , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/genética , Técnicas de Introdução de Genes , Células HEK293 , Hipocampo/citologia , Hipocampo/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Moleculares , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Fosforilação , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Células de Purkinje/citologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Sinapses/fisiologia , Transmissão Sináptica
7.
N Engl J Med ; 389(5): 393-405, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37530822

RESUMO

BACKGROUND: The NaV1.8 voltage-gated sodium channel, expressed in peripheral nociceptive neurons, plays a role in transmitting nociceptive signals. The effect of VX-548, an oral, highly selective inhibitor of NaV1.8, on control of acute pain is being studied. METHODS: After establishing the selectivity of VX-548 for NaV1.8 inhibition in vitro, we conducted two phase 2 trials involving participants with acute pain after abdominoplasty or bunionectomy. In the abdominoplasty trial, participants were randomly assigned in a 1:1:1:1 ratio to receive one of the following over a 48-hour period: a 100-mg oral loading dose of VX-548, followed by a 50-mg maintenance dose every 12 hours (the high-dose group); a 60-mg loading dose of VX-548, followed by a 30-mg maintenance dose every 12 hours (the middle-dose group); hydrocodone bitartrate-acetaminophen (5 mg of hydrocodone bitartrate and 325 mg of acetaminophen every 6 hours); or oral placebo every 6 hours. In the bunionectomy trial, participants were randomly assigned in a 2:2:1:2:2 ratio to receive one of the following over a 48-hour treatment period: oral high-dose VX-548; middle-dose VX-548; low-dose VX-548 (a 20-mg loading dose, followed by a 10-mg maintenance dose every 12 hours); oral hydrocodone bitartrate-acetaminophen (5 mg of hydrocodone bitartrate and 325 mg of acetaminophen every 6 hours); or oral placebo every 6 hours. The primary end point was the time-weighted sum of the pain-intensity difference (SPID) over the 48-hour period (SPID48), a measure derived from the score on the Numeric Pain Rating Scale (range, 0 to 10; higher scores indicate greater pain) at 19 time points after the first dose of VX-548 or placebo. The main analysis compared each dose of VX-548 with placebo. RESULTS: A total of 303 participants were enrolled in the abdominoplasty trial and 274 in the bunionectomy trial. The least-squares mean difference between the high-dose VX-548 and placebo groups in the time-weighted SPID48 was 37.8 (95% confidence interval [CI], 9.2 to 66.4) after abdominoplasty and 36.8 (95% CI, 4.6 to 69.0) after bunionectomy. In both trials, participants who received lower doses of VX-548 had results similar to those with placebo. Headache and constipation were common adverse events with VX-548. CONCLUSIONS: As compared with placebo, VX-548 at the highest dose, but not at lower doses, reduced acute pain over a period of 48 hours after abdominoplasty or bunionectomy. VX-548 was associated with adverse events that were mild to moderate in severity. (Funded by Vertex Pharmaceuticals; VX21-548-101 and VX21-548-102 ClinicalTrials.gov numbers, NCT04977336 and NCT05034952.).


Assuntos
Acetaminofen , Dor Aguda , Humanos , Acetaminofen/uso terapêutico , Hidrocodona/efeitos adversos , Dor Aguda/tratamento farmacológico , Analgésicos Opioides/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Analgésicos/uso terapêutico , Método Duplo-Cego
8.
Nat Methods ; 20(7): 1010-1020, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37202537

RESUMO

The Cell Tracking Challenge is an ongoing benchmarking initiative that has become a reference in cell segmentation and tracking algorithm development. Here, we present a significant number of improvements introduced in the challenge since our 2017 report. These include the creation of a new segmentation-only benchmark, the enrichment of the dataset repository with new datasets that increase its diversity and complexity, and the creation of a silver standard reference corpus based on the most competitive results, which will be of particular interest for data-hungry deep learning-based strategies. Furthermore, we present the up-to-date cell segmentation and tracking leaderboards, an in-depth analysis of the relationship between the performance of the state-of-the-art methods and the properties of the datasets and annotations, and two novel, insightful studies about the generalizability and the reusability of top-performing methods. These studies provide critical practical conclusions for both developers and users of traditional and machine learning-based cell segmentation and tracking algorithms.


Assuntos
Benchmarking , Rastreamento de Células , Rastreamento de Células/métodos , Aprendizado de Máquina , Algoritmos
9.
Circ Res ; 134(2): 143-161, 2024 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-38156445

RESUMO

BACKGROUND: Single-nucleotide polymorphisms linked with the rs1474868 T allele (MFN2 [mitofusin-2] T/T) in the human mitochondrial fusion protein MFN2 gene are associated with reduced platelet MFN2 RNA expression and platelet counts. This study investigates the impact of MFN2 on megakaryocyte and platelet biology. METHODS: Mice with megakaryocyte/platelet deletion of Mfn2 (Mfn2-/- [Mfn2 conditional knockout]) were generated using Pf4-Cre crossed with floxed Mfn2 mice. Human megakaryocytes were generated from cord blood and platelets isolated from healthy subjects genotyped for rs1474868. Ex vivo approaches assessed mitochondrial morphology, function, and platelet activation responses. In vivo measurements included endogenous/transfused platelet life span, tail bleed time, transient middle cerebral artery occlusion, and pulmonary vascular permeability/hemorrhage following lipopolysaccharide-induced acute lung injury. RESULTS: Mitochondria was more fragmented in megakaryocytes derived from Mfn2-/- mice and from human cord blood with MFN2 T/T genotype compared with control megakaryocytes. Human resting platelets of MFN2 T/T genotype had reduced MFN2 protein, diminished mitochondrial membrane potential, and an increased rate of phosphatidylserine exposure during ex vivo culture. Platelet counts and platelet life span were reduced in Mfn2-/- mice accompanied by an increased rate of phosphatidylserine exposure in resting platelets, especially aged platelets, during ex vivo culture. Mfn2-/- also decreased platelet mitochondrial membrane potential (basal) and activated mitochondrial oxygen consumption rate, reactive oxygen species generation, calcium flux, platelet-neutrophil aggregate formation, and phosphatidylserine exposure following dual agonist activation. Ultimately, Mfn2-/- mice showed prolonged tail bleed times, decreased ischemic stroke infarct size after cerebral ischemia-reperfusion, and exacerbated pulmonary inflammatory hemorrhage following lipopolysaccharide-induced acute lung injury. Analysis of MFN2 SNPs in the iSPAAR study (Identification of SNPs Predisposing to Altered ALI Risk) identified a significant association between MFN2 and 28-day mortality in patients with acute respiratory distress syndrome. CONCLUSIONS: Mfn2 preserves mitochondrial phenotypes in megakaryocytes and platelets and influences platelet life span, function, and outcomes of stroke and lung injury.


Assuntos
Lesão Pulmonar Aguda , Lipopolissacarídeos , Idoso , Animais , Humanos , Camundongos , Lesão Pulmonar Aguda/metabolismo , Plaquetas/metabolismo , Hemorragia/metabolismo , Mitocôndrias/metabolismo , Fosfatidilserinas/metabolismo
10.
Cell ; 147(3): 615-28, 2011 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-22036569

RESUMO

Assemblies of ß-amyloid (Aß) peptides are pathological mediators of Alzheimer's Disease (AD) and are produced by the sequential cleavages of amyloid precursor protein (APP) by ß-secretase (BACE1) and γ-secretase. The generation of Aß is coupled to neuronal activity, but the molecular basis is unknown. Here, we report that the immediate early gene Arc is required for activity-dependent generation of Aß. Arc is a postsynaptic protein that recruits endophilin2/3 and dynamin to early/recycling endosomes that traffic AMPA receptors to reduce synaptic strength in both hebbian and non-hebbian forms of plasticity. The Arc-endosome also traffics APP and BACE1, and Arc physically associates with presenilin1 (PS1) to regulate γ-secretase trafficking and confer activity dependence. Genetic deletion of Arc reduces Aß load in a transgenic mouse model of AD. In concert with the finding that patients with AD can express anomalously high levels of Arc, we hypothesize that Arc participates in the pathogenesis of AD.


Assuntos
Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Proteínas do Citoesqueleto/metabolismo , Endossomos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Transporte Proteico , Animais , Membrana Celular/metabolismo , Humanos , Camundongos , Camundongos Knockout
11.
Cell ; 145(5): 758-72, 2011 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-21565394

RESUMO

We have created a mouse genetic model that mimics a human mutation of Shank3 that deletes the C terminus and is associated with autism. Expressed as a single copy [Shank3(+/ΔC) mice], Shank3ΔC protein interacts with the wild-type (WT) gene product and results in >90% reduction of Shank3 at synapses. This "gain-of-function" phenotype is linked to increased polyubiquitination of WT Shank3 and its redistribution into proteasomes. Similarly, the NR1 subunit of the NMDA receptor is reduced at synapses with increased polyubiquitination. Assays of postsynaptic density proteins, spine morphology, and synapse number are unchanged in Shank3(+/ΔC) mice, but the amplitude of NMDAR responses is reduced together with reduced NMDAR-dependent LTP and LTD. Reciprocally, mGluR-dependent LTD is markedly enhanced. Shank3(+/ΔC) mice show behavioral deficits suggestive of autism and reduced NMDA receptor function. These studies reveal a mechanism distinct from haploinsufficiency by which mutations of Shank3 can evoke an autism-like disorder.


Assuntos
Transtorno Autístico/genética , Proteínas de Transporte/metabolismo , Modelos Animais de Doenças , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Transtorno Autístico/metabolismo , Transtorno Autístico/fisiopatologia , Proteínas de Transporte/genética , Hipocampo/metabolismo , Humanos , Relações Interpessoais , Potenciação de Longa Duração , Depressão Sináptica de Longo Prazo , Camundongos , Proteínas dos Microfilamentos , Proteínas do Tecido Nervoso , Receptores de Glutamato Metabotrópico/metabolismo , Sinapses/metabolismo , Ubiquitinação
12.
Nature ; 577(7792): E9, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31925404

RESUMO

An Amendment to this paper has been published and can be accessed via a link at the top of the paper.

13.
Nature ; 586(7831): 724-729, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33057198

RESUMO

Extensive ecosystem restoration is increasingly seen as being central to conserving biodiversity1 and stabilizing the climate of the Earth2. Although ambitious national and global targets have been set, global priority areas that account for spatial variation in benefits and costs have yet to be identified. Here we develop and apply a multicriteria optimization approach that identifies priority areas for restoration across all terrestrial biomes, and estimates their benefits and costs. We find that restoring 15% of converted lands in priority areas could avoid 60% of expected extinctions while sequestering 299 gigatonnes of CO2-30% of the total CO2 increase in the atmosphere since the Industrial Revolution. The inclusion of several biomes is key to achieving multiple benefits. Cost effectiveness can increase up to 13-fold when spatial allocation is optimized using our multicriteria approach, which highlights the importance of spatial planning. Our results confirm the vast potential contributions of restoration to addressing global challenges, while underscoring the necessity of pursuing these goals synergistically.


Assuntos
Ecossistema , Recuperação e Remediação Ambiental/tendências , Cooperação Internacional , Animais , Biodiversidade , Conservação dos Recursos Naturais/economia , Análise Custo-Benefício , Recuperação e Remediação Ambiental/economia , Mapeamento Geográfico , Aquecimento Global/economia , Aquecimento Global/prevenção & controle
14.
Proc Natl Acad Sci U S A ; 120(12): e2214225120, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36917668

RESUMO

A murine papillomavirus, MmuPV1, infects both cutaneous and mucosal epithelia of laboratory mice and can be used to model high-risk human papillomavirus (HPV) infection and HPV-associated disease. We have shown that estrogen exacerbates papillomavirus-induced cervical disease in HPV-transgenic mice. We have also previously identified stress keratin 17 (K17) as a host factor that supports MmuPV1-induced cutaneous disease. Here, we sought to test the role of estrogen and K17 in MmuPV1 infection and associated disease in the female reproductive tract. We experimentally infected wild-type and K17 knockout (K17KO) mice with MmuPV1 in the female reproductive tract in the presence or absence of exogenous estrogen for 6 mon. We observed that a significantly higher percentage of K17KO mice cleared the virus as opposed to wild-type mice. In estrogen-treated wild-type mice, the MmuPV1 viral copy number was significantly higher compared to untreated mice by as early as 2 wk postinfection, suggesting that estrogen may help facilitate MmuPV1 infection and/or establishment. Consistent with this, viral clearance was not observed in either wild-type or K17KO mice when treated with estrogen. Furthermore, neoplastic disease progression and cervical carcinogenesis were supported by the presence of K17 and exacerbated by estrogen treatment. Subsequent analyses indicated that estrogen treatment induces a systemic immunosuppressive state in MmuPV1-infected animals and that both estrogen and K17 modulate the local intratumoral immune microenvironment within MmuPV1-induced neoplastic lesions. Collectively, these findings suggest that estrogen and K17 act at multiple stages of papillomavirus-induced disease at least in part via immunomodulatory mechanisms.


Assuntos
Infecções por Papillomavirus , Camundongos , Feminino , Humanos , Animais , Infecções por Papillomavirus/genética , Queratina-17 , Camundongos Transgênicos , Imunidade , Papillomaviridae/genética , Estrogênios
15.
PLoS Genet ; 19(2): e1010624, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36749789

RESUMO

Polygenic risk scores (PRSs) have been among the leading advances in biomedicine in recent years. As a proxy of genetic liability, PRSs are utilised across multiple fields and applications. While numerous statistical and machine learning methods have been developed to optimise their predictive accuracy, these typically distil genetic liability to a single number based on aggregation of an individual's genome-wide risk alleles. This results in a key loss of information about an individual's genetic profile, which could be critical given the functional sub-structure of the genome and the heterogeneity of complex disease. In this manuscript, we introduce a 'pathway polygenic' paradigm of disease risk, in which multiple genetic liabilities underlie complex diseases, rather than a single genome-wide liability. We describe a method and accompanying software, PRSet, for computing and analysing pathway-based PRSs, in which polygenic scores are calculated across genomic pathways for each individual. We evaluate the potential of pathway PRSs in two distinct ways, creating two major sections: (1) In the first section, we benchmark PRSet as a pathway enrichment tool, evaluating its capacity to capture GWAS signal in pathways. We find that for target sample sizes of >10,000 individuals, pathway PRSs have similar power for evaluating pathway enrichment as leading methods MAGMA and LD score regression, with the distinct advantage of providing individual-level estimates of genetic liability for each pathway -opening up a range of pathway-based PRS applications, (2) In the second section, we evaluate the performance of pathway PRSs for disease stratification. We show that using a supervised disease stratification approach, pathway PRSs (computed by PRSet) outperform two standard genome-wide PRSs (computed by C+T and lassosum) for classifying disease subtypes in 20 of 21 scenarios tested. As the definition and functional annotation of pathways becomes increasingly refined, we expect pathway PRSs to offer key insights into the heterogeneity of complex disease and treatment response, to generate biologically tractable therapeutic targets from polygenic signal, and, ultimately, to provide a powerful path to precision medicine.


Assuntos
Genômica , Herança Multifatorial , Humanos , Fatores de Risco , Herança Multifatorial/genética , Estudo de Associação Genômica Ampla , Software , Predisposição Genética para Doença
16.
Proc Natl Acad Sci U S A ; 120(32): e2302151120, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37523553

RESUMO

Polyelectrolyte complexation plays an important role in materials science and biology. The internal structure of the resultant polyelectrolyte complex (PEC) phase dictates properties such as physical state, response to external stimuli, and dynamics. Small-angle scattering experiments with X-rays and neutrons have revealed structural similarities between PECs and semidilute solutions of neutral polymers, where the total scattering function exhibits an Ornstein-Zernike form. In spite of consensus among different theoretical predictions, the existence of positional correlations between polyanion and polycation charges has not been confirmed experimentally. Here, we present small-angle neutron scattering profiles where the polycation scattering length density is matched to that of the solvent to extract positional correlations among anionic monomers. The polyanion scattering functions exhibit a peak at the inverse polymer screening radius of Coulomb interactions, q* ≈ 0.2 Å-1. This peak, attributed to Coulomb repulsions between the fragments of polyanions and their attractions to polycations, is even more pronounced in the calculated charge scattering function that quantifies positional correlations of all polymer charges within the PEC. Screening of electrostatic interactions by adding salt leads to the gradual disappearance of this correlation peak, and the scattering functions regain an Ornstein-Zernike form. Experimental scattering results are consistent with those calculated from the random phase approximation, a scaling analysis, and molecular simulations.

17.
Proc Natl Acad Sci U S A ; 120(14): e2216700120, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36989302

RESUMO

Chromosome segregation during mitosis is highly regulated to ensure production of genetically identical progeny. Recurrent mitotic errors cause chromosomal instability (CIN), a hallmark of tumors. The E6 and E7 oncoproteins of high-risk human papillomavirus (HPV), which causes cervical, anal, and head and neck cancers (HNC), cause mitotic defects consistent with CIN in models of anogenital cancers, but this has not been studied in the context of HNC. Here, we show that HPV16 induces a specific type of CIN in patient HNC tumors, patient-derived xenografts, and cell lines, which is due to defects in chromosome congression. These defects are specifically induced by the HPV16 oncogene E6 rather than E7. We show that HPV16 E6 expression causes degradation of the mitotic kinesin CENP-E, whose depletion produces chromosomes that are chronically misaligned near spindle poles (polar chromosomes) and fail to congress. Though the canonical oncogenic role of E6 is the degradation of the tumor suppressor p53, CENP-E degradation and polar chromosomes occur independently of p53. Instead, E6 directs CENP-E degradation in a proteasome-dependent manner via the E6-associated ubiquitin protein ligase E6AP/UBE3A. This study reveals a mechanism by which HPV induces CIN, which may impact HPV-mediated tumor initiation, progression, and therapeutic response.


Assuntos
Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Humanos , Instabilidade Cromossômica , Cromossomos/metabolismo , Papillomavirus Humano 16/genética , Cinesinas/genética , Cinesinas/metabolismo , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
18.
Proc Natl Acad Sci U S A ; 120(45): e2308655120, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37903249

RESUMO

The ongoing SARS-CoV-2 epidemic was marked by the repeated emergence and replacement of "variants" with genetic and phenotypic distance from the ancestral strains, the most recent examples being viruses of the Omicron lineage. Here, we describe a hamster direct contact exposure challenge model to assess protection against reinfection conferred by either vaccination or prior infection. We found that two doses of self-amplifying RNA vaccine based on the ancestral Spike ameliorated weight loss following Delta infection and decreased viral loads but had minimal effect on Omicron BA.1 infection. Prior vaccination followed by Delta or BA.1 breakthrough infections led to a high degree of cross-reactivity to all tested variants, suggesting that repeated exposure to antigenically distinct Spikes, via infection and/or vaccination drives a cross-reactive immune response. Prior infection with ancestral or Alpha variant was partially protective against BA.1 infection, whereas all animals previously infected with Delta and exposed to BA.1 became reinfected, although they shed less virus than BA.1-infected naive hamsters. Hamsters reinfected with BA.1 after prior Delta infection emitted infectious virus into the air, indicating that they could be responsible for onwards airborne transmission. We further tested whether prior infection with BA.1 protected from reinfection with Delta or later Omicron sublineages BA.2, BA.4, or BA.5. BA.1 was protective against BA.2 but not against Delta, BA.4, or BA.5 reinfection. These findings suggest that cohorts whose only immune experience of COVID-19 is Omicron BA.1 infection may be vulnerable to future circulation of reemerged Delta-like derivatives, as well as emerging Omicron sublineages.


Assuntos
COVID-19 , Hepatite D , Animais , Cricetinae , Infecções Irruptivas , Reinfecção , Reações Cruzadas , Anticorpos Neutralizantes , Anticorpos Antivirais
19.
Plant J ; 119(1): 383-403, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38625758

RESUMO

Hemp (Cannabis sativa L.) is an extraordinarily versatile crop, with applications ranging from medicinal compounds to seed oil and fibre products. Cannabis sativa is a short-day plant, and its flowering is highly controlled by photoperiod. However, substantial genetic variation exists for photoperiod sensitivity in C. sativa, and photoperiod-insensitive ("autoflower") cultivars are available. Using a bi-parental mapping population and bulked segregant analysis, we identified Autoflower2, a 0.5 Mbp locus significantly associated with photoperiod-insensitive flowering in hemp. Autoflower2 contains an ortholog of the central flowering time regulator FLOWERING LOCUS T (FT) from Arabidopsis thaliana which we termed CsFT1. We identified extensive sequence divergence between alleles of CsFT1 from photoperiod-sensitive and insensitive cultivars of C. sativa, including a duplication of CsFT1 and sequence differences, especially in introns. Furthermore, we observed higher expression of one of the CsFT1 copies found in the photoperiod-insensitive cultivar. Genotyping of several mapping populations and a diversity panel confirmed a correlation between CsFT1 alleles and photoperiod response, affirming that at least two independent loci involved in the photoperiodic control of flowering, Autoflower1 and Autoflower2, exist in the C. sativa gene pool. This study reveals the multiple independent origins of photoperiod insensitivity in C. sativa, supporting the likelihood of a complex domestication history in this species. By integrating the genetic relaxation of photoperiod sensitivity into novel C. sativa cultivars, expansion to higher latitudes will be permitted, thus allowing the full potential of this versatile crop to be reached.


Assuntos
Cannabis , Flores , Fotoperíodo , Proteínas de Plantas , Flores/genética , Flores/fisiologia , Cannabis/genética , Cannabis/fisiologia , Cannabis/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Alelos , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Mapeamento Cromossômico
20.
Am J Hum Genet ; 109(1): 12-23, 2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34995502

RESUMO

The low portability of polygenic scores (PGSs) across global populations is a major concern that must be addressed before PGSs can be used for everyone in the clinic. Indeed, prediction accuracy has been shown to decay as a function of the genetic distance between the training and test cohorts. However, such cohorts differ not only in their genetic distance but also in their geographical distance and their data collection and assaying, conflating multiple factors. In this study, we examine the extent to which PGSs are transferable between ancestries by deriving polygenic scores for 245 curated traits from the UK Biobank data and applying them in nine ancestry groups from the same cohort. By restricting both training and testing to the UK Biobank data, we reduce the risk of environmental and genotyping confounding from using different cohorts. We define the nine ancestry groups at a sub-continental level, based on a simple, robust, and effective method that we introduce here. We then apply two different predictive methods to derive polygenic scores for all 245 phenotypes and show a systematic and dramatic reduction in portability of PGSs trained using Northwestern European individuals and applied to nine ancestry groups. These analyses demonstrate that prediction already drops off within European ancestries and reduces globally in proportion to genetic distance. Altogether, our study provides unique and robust insights into the PGS portability problem.


Assuntos
Estudos de Associação Genética/métodos , Predisposição Genética para Doença , Genética Populacional/métodos , Herança Multifatorial , Algoritmos , Alelos , Bancos de Espécimes Biológicos , Variação Genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Modelos Genéticos , Fenótipo , Reprodutibilidade dos Testes , Reino Unido
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA