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MXRA8 is a receptor for chikungunya (CHIKV) and other arthritogenic alphaviruses with mammalian hosts. However, mammalian MXRA8 does not bind to alphaviruses that infect humans and have avian reservoirs. Here, we show that avian, but not mammalian, MXRA8 can act as a receptor for Sindbis, western equine encephalitis (WEEV), and related alphaviruses with avian reservoirs. Structural analysis of duck MXRA8 complexed with WEEV reveals an inverted binding mode compared with mammalian MXRA8 bound to CHIKV. Whereas both domains of mammalian MXRA8 bind CHIKV E1 and E2, only domain 1 of avian MXRA8 engages WEEV E1, and no appreciable contacts are made with WEEV E2. Using these results, we generated a chimeric avian-mammalian MXRA8 decoy-receptor that neutralizes infection of multiple alphaviruses from distinct antigenic groups in vitro and in vivo. Thus, different alphaviruses can bind MXRA8 encoded by different vertebrate classes with distinct engagement modes, which enables development of broad-spectrum inhibitors.
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Alphavirus , Animais , Humanos , Febre de Chikungunya , Vírus Chikungunya/química , Mamíferos , Receptores Virais/metabolismoRESUMO
Mxra8 is a receptor for multiple arthritogenic alphaviruses that cause debilitating acute and chronic musculoskeletal disease in humans. Herein, we present a 2.2 Å resolution X-ray crystal structure of Mxra8 and 4 to 5 Å resolution cryo-electron microscopy reconstructions of Mxra8 bound to chikungunya (CHIKV) virus-like particles and infectious virus. The Mxra8 ectodomain contains two strand-swapped Ig-like domains oriented in a unique disulfide-linked head-to-head arrangement. Mxra8 binds by wedging into a cleft created by two adjacent CHIKV E2-E1 heterodimers in one trimeric spike and engaging a neighboring spike. Two binding modes are observed with the fully mature VLP, with one Mxra8 binding with unique contacts. Only the high-affinity binding mode was observed in the complex with infectious CHIKV, as viral maturation and E3 occupancy appear to influence receptor binding-site usage. Our studies provide insight into how Mxra8 binds CHIKV and creates a path for developing alphavirus entry inhibitors.
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Vírus Chikungunya/química , Proteínas de Membrana/química , Proteínas do Envelope Viral/química , Vírus Chikungunya/metabolismo , Vírus Chikungunya/ultraestrutura , Microscopia Crioeletrônica , Células HEK293 , Humanos , Proteínas de Membrana/metabolismo , Domínios Proteicos , Proteínas do Envelope Viral/metabolismoRESUMO
Zika virus (ZIKV) infection during pregnancy has emerged as a global public health problem because of its ability to cause severe congenital disease. Here, we developed six mouse monoclonal antibodies (mAbs) against ZIKV including four (ZV-48, ZV-54, ZV-64, and ZV-67) that were ZIKV specific and neutralized infection of African, Asian, and American strains to varying degrees. X-ray crystallographic and competition binding analyses of Fab fragments and scFvs defined three spatially distinct epitopes in DIII of the envelope protein corresponding to the lateral ridge (ZV-54 and ZV-67), C-C' loop (ZV-48 and ZV-64), and ABDE sheet (ZV-2) regions. In vivo passive transfer studies revealed protective activity of DIII-lateral ridge specific neutralizing mAbs in a mouse model of ZIKV infection. Our results suggest that DIII is targeted by multiple type-specific antibodies with distinct neutralizing activity, which provides a path for developing prophylactic antibodies for use in pregnancy or designing epitope-specific vaccines against ZIKV.
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Anticorpos Monoclonais/química , Anticorpos Antivirais/química , Proteínas do Envelope Viral/química , Zika virus/química , Zika virus/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/imunologia , Mapeamento de Epitopos , Epitopos , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Zika virus/classificação , Infecção por Zika virus/imunologia , Infecção por Zika virus/virologiaRESUMO
Dissecting the evolution of memory B cells (MBCs) against SARS-CoV-2 is critical for understanding antibody recall upon secondary exposure. Here, we used single-cell sequencing to profile SARS-CoV-2-reactive B cells in 38 COVID-19 patients. Using oligo-tagged antigen baits, we isolated B cells specific to the SARS-CoV-2 spike, nucleoprotein (NP), open reading frame 8 (ORF8), and endemic human coronavirus (HCoV) spike proteins. SARS-CoV-2 spike-specific cells were enriched in the memory compartment of acutely infected and convalescent patients several months post symptom onset. With severe acute infection, substantial populations of endemic HCoV-reactive antibody-secreting cells were identified and possessed highly mutated variable genes, signifying preexisting immunity. Finally, MBCs exhibited pronounced maturation to NP and ORF8 over time, especially in older patients. Monoclonal antibodies against these targets were non-neutralizing and non-protective in vivo. These findings reveal antibody adaptation to non-neutralizing intracellular antigens during infection, emphasizing the importance of vaccination for inducing neutralizing spike-specific MBCs.
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Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Linfócitos B/imunologia , COVID-19/imunologia , Interações Hospedeiro-Patógeno/imunologia , Epitopos Imunodominantes/imunologia , SARS-CoV-2/imunologia , Anticorpos Neutralizantes/imunologia , Formação de Anticorpos/genética , Linfócitos B/metabolismo , Biologia Computacional/métodos , Reações Cruzadas/imunologia , Mapeamento de Epitopos , Feminino , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Interações Hospedeiro-Patógeno/genética , Humanos , Epitopos Imunodominantes/genética , Memória Imunológica , Masculino , Testes de Neutralização , Análise de Célula Única/métodos , Glicoproteína da Espícula de Coronavírus/imunologia , TranscriptomaRESUMO
LDLRAD3 is a recently defined attachment and entry receptor for Venezuelan equine encephalitis virus (VEEV)1, a New World alphavirus that causes severe neurological disease in humans. Here we present near-atomic-resolution cryo-electron microscopy reconstructions of VEEV virus-like particles alone and in a complex with the ectodomains of LDLRAD3. Domain 1 of LDLRAD3 is a low-density lipoprotein receptor type-A module that binds to VEEV by wedging into a cleft created by two adjacent E2-E1 heterodimers in one trimeric spike, and engages domains A and B of E2 and the fusion loop in E1. Atomic modelling of this interface is supported by mutagenesis and anti-VEEV antibody binding competition assays. Notably, VEEV engages LDLRAD3 in a manner that is similar to the way that arthritogenic alphaviruses bind to the structurally unrelated MXRA8 receptor, but with a much smaller interface. These studies further elucidate the structural basis of alphavirus-receptor interactions, which could inform the development of therapies to mitigate infection and disease against multiple members of this family.
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Vírus da Encefalite Equina Venezuelana/química , Receptores de LDL/química , Receptores Virais/química , Sequência de Aminoácidos , Animais , Linhagem Celular , Microscopia Crioeletrônica , Humanos , Camundongos , Modelos Moleculares , Estrutura Secundária de Proteína , Alinhamento de Sequência , Internalização do VírusRESUMO
Venezuelan equine encephalitis virus (VEEV) is a neurotropic alphavirus transmitted by mosquitoes that causes encephalitis and death in humans1. VEEV is a biodefence concern because of its potential for aerosol spread and the current lack of sufficient countermeasures. The host factors that are required for VEEV entry and infection remain poorly characterized. Here, using a genome-wide CRISPR-Cas9-based screen, we identify low-density lipoprotein receptor class A domain-containing 3 (LDLRAD3)-a highly conserved yet poorly characterized member of the scavenger receptor superfamily-as a receptor for VEEV. Gene editing of mouse Ldlrad3 or human LDLRAD3 results in markedly reduced viral infection of neuronal cells, which is restored upon complementation with LDLRAD3. LDLRAD3 binds directly to VEEV particles and enhances virus attachment and internalization into host cells. Genetic studies indicate that domain 1 of LDLRAD3 (LDLRAD3(D1)) is necessary and sufficient to support infection by VEEV, and both anti-LDLRAD3 antibodies and an LDLRAD3(D1)-Fc fusion protein block VEEV infection in cell culture. The pathogenesis of VEEV infection is abrogated in mice with deletions in Ldlrad3, and administration of LDLRAD3(D1)-Fc abolishes disease caused by several subtypes of VEEV, including highly virulent strains. The development of a decoy-receptor fusion protein suggests a strategy for the prevention of severe VEEV infection and associated disease in humans.
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Vírus da Encefalite Equina Venezuelana/metabolismo , Receptores de LDL/metabolismo , Receptores Virais/metabolismo , Animais , Sistemas CRISPR-Cas/genética , Linhagem Celular , Vírus da Encefalite Equina Venezuelana/patogenicidade , Encefalomielite Equina Venezuelana/metabolismo , Encefalomielite Equina Venezuelana/prevenção & controle , Encefalomielite Equina Venezuelana/virologia , Feminino , Teste de Complementação Genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ligação Proteica , Receptores de LDL/deficiência , Receptores de LDL/genética , Receptores Virais/genética , Ligação Viral , Internalização do VírusRESUMO
Myeloproliferative neoplasms (MPNs) are blood cancers that are characterized by the excessive production of mature myeloid cells and arise from the acquisition of somatic driver mutations in haematopoietic stem cells (HSCs). Epidemiological studies indicate a substantial heritable component of MPNs that is among the highest known for cancers1. However, only a limited number of genetic risk loci have been identified, and the underlying biological mechanisms that lead to the acquisition of MPNs remain unclear. Here, by conducting a large-scale genome-wide association study (3,797 cases and 1,152,977 controls), we identify 17 MPN risk loci (P < 5.0 × 10-8), 7 of which have not been previously reported. We find that there is a shared genetic architecture between MPN risk and several haematopoietic traits from distinct lineages; that there is an enrichment for MPN risk variants within accessible chromatin of HSCs; and that increased MPN risk is associated with longer telomere length in leukocytes and other clonal haematopoietic states-collectively suggesting that MPN risk is associated with the function and self-renewal of HSCs. We use gene mapping to identify modulators of HSC biology linked to MPN risk, and show through targeted variant-to-function assays that CHEK2 and GFI1B have roles in altering the function of HSCs to confer disease risk. Overall, our results reveal a previously unappreciated mechanism for inherited MPN risk through the modulation of HSC function.
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Predisposição Genética para Doença/genética , Células-Tronco Hematopoéticas/patologia , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/patologia , Neoplasias/genética , Neoplasias/patologia , Linhagem da Célula/genética , Autorrenovação Celular , Quinase do Ponto de Checagem 2/genética , Feminino , Humanos , Leucócitos/patologia , Masculino , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Risco , Homeostase do TelômeroRESUMO
In this Letter, the first name of author Bhagwati Prasad was misspelled Bhagawati. This error has been corrected online.
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Negative capacitance is a newly discovered state of ferroelectric materials that holds promise for electronics applications by exploiting a region of thermodynamic space that is normally not accessible1-14. Although existing reports of negative capacitance substantiate the importance of this phenomenon, they have focused on its macroscale manifestation. These manifestations demonstrate possible uses of steady-state negative capacitance-for example, enhancing the capacitance of a ferroelectric-dielectric heterostructure4,7,14 or improving the subthreshold swing of a transistor8-12. Yet they constitute only indirect measurements of the local state of negative capacitance in which the ferroelectric resides. Spatial mapping of this phenomenon would help its understanding at a microscopic scale and also help to achieve optimal design of devices with potential technological applications. Here we demonstrate a direct measurement of steady-state negative capacitance in a ferroelectric-dielectric heterostructure. We use electron microscopy complemented by phase-field and first-principles-based (second-principles) simulations in SrTiO3/PbTiO3 superlattices to directly determine, with atomic resolution, the local regions in the ferroelectric material where a state of negative capacitance is stabilized. Simultaneous vector mapping of atomic displacements (related to a complex pattern in the polarization field), in conjunction with reconstruction of the local electric field, identify the negative capacitance regions as those with higher energy density and larger polarizability: the domain walls where the polarization is suppressed.
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[This corrects the article DOI: 10.1371/journal.pgen.1008835.].
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BACKGROUND AND AIMS: A cardiovascular disease polygenic risk score (CVD-PRS) can stratify individuals into different categories of cardiovascular risk, but whether the addition of a CVD-PRS to clinical risk scores improves the identification of individuals at increased risk in a real-world clinical setting is unknown. METHODS: The Genetics and the Vascular Health Check Study (GENVASC) was embedded within the UK National Health Service Health Check (NHSHC) programme which invites individuals between 40-74 years of age without known CVD to attend an assessment in a UK general practice where CVD risk factors are measured and a CVD risk score (QRISK2) is calculated. Between 2012-2020, 44,141 individuals (55.7% females, 15.8% non-white) who attended an NHSHC in 147 participating practices across two counties in England were recruited and followed. When 195 individuals (cases) had suffered a major CVD event (CVD death, myocardial infarction or acute coronary syndrome, coronary revascularisation, stroke), 396 propensity-matched controls with a similar risk profile were identified, and a nested case-control genetic study undertaken to see if the addition of a CVD-PRS to QRISK2 in the form of an integrated risk tool (IRT) combined with QRISK2 would have identified more individuals at the time of their NHSHC as at high risk (QRISK2 10-year CVD risk of ≥10%), compared with QRISK2 alone. RESULTS: The distribution of the standardised CVD-PRS was significantly different in cases compared with controls (cases mean score .32; controls, -.18, P = 8.28×10-9). QRISK2 identified 61.5% (95% confidence interval [CI]: 54.3%-68.4%) of individuals who subsequently developed a major CVD event as being at high risk at their NHSHC, while the combination of QRISK2 and IRT identified 68.7% (95% CI: 61.7%-75.2%), a relative increase of 11.7% (P = 1×10-4). The odds ratio (OR) of being up-classified was 2.41 (95% CI: 1.03-5.64, P = .031) for cases compared with controls. In individuals aged 40-54 years, QRISK2 identified 26.0% (95% CI: 16.5%-37.6%) of those who developed a major CVD event, while the combination of QRISK2 and IRT identified 38.4% (95% CI: 27.2%-50.5%), indicating a stronger relative increase of 47.7% in the younger age group (P = .001). The combination of QRISK2 and IRT increased the proportion of additional cases identified similarly in women as in men, and in non-white ethnicities compared with white ethnicity. The findings were similar when the CVD-PRS was added to the atherosclerotic cardiovascular disease pooled cohort equations (ASCVD-PCE) or SCORE2 clinical scores. CONCLUSIONS: In a clinical setting, the addition of genetic information to clinical risk assessment significantly improved the identification of individuals who went on to have a major CVD event as being at high risk, especially among younger individuals. The findings provide important real-world evidence of the potential value of implementing a CVD-PRS into health systems.
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Platelet transfusion and transplantation of allogeneic stem cells and solid organs are life-saving therapies. Unwanted alloantibodies to nonself human leukocyte antigens (HLAs) on donor cells increase the immunological barrier to these therapies and are important causes of platelet transfusion refractoriness and graft rejection. Although the specificities of anti-HLA antibodies can be determined at the allelic level, traditional treatments for antibody-mediated rejection nonselectively suppress humoral immunity and are not universally successful. We designed HLA-Fc fusion proteins with a bivalent targeting module derived from extracellular domains of HLA and an Fc effector module from mouse IgG2a. We found that HLA-Fc with A2 (A2Fc) and B7 (B7Fc) antigens lowered HLA-A2- and HLA-B7-specific reactivities, respectively, in sera from HLA-sensitized patients. A2Fc and B7Fc bound to B-cell hybridomas bearing surface immunoglobulins with cognate specificities and triggered antigen-specific and Fc-dependent cytotoxicity in vitro. In immunodeficient mice carrying HLA-A2-specific hybridoma cells, A2Fc treatment lowered circulating anti-HLA-A2 levels, abolished the outgrowth of hybridoma cells, and prolonged survival compared with control groups. In an in vivo anti-HLA-A2-mediated platelet transfusion refractoriness model, A2Fc treatment mitigated refractoriness. These results support HLA-Fc being a novel strategy for antigen-specific humoral suppression to improve transfusion and transplantation outcomes. With the long-term goal of targeting HLA-specific memory B cells for desensitization, further studies of HLA-Fc's efficacy in immune-competent animal models are warranted.
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Isoanticorpos , Trombocitopenia , Humanos , Camundongos , Animais , Antígeno HLA-B7 , Antígenos HLA , Rejeição de Enxerto , Soro Antilinfocitário , Antígeno HLA-A2 , Células Produtoras de Anticorpos , Imunoglobulina G , Receptores de Antígenos de Linfócitos BRESUMO
PURPOSE: To investigate whether micronutrient intake from food as well as the regular uptake of specific vitamins and/or minerals are associated with leucocyte telomere length (LTL). METHODS: This is a cross-sectional study using data from 422,693 UK Biobank participants aged from 40 to 69 years old, during 2006-2010. LTL was measured as the ratio of telomere repeat number to a single-copy gene and was loge-transformed and z-standardized (z-LTL). Information concerning supplement use was collected at baseline through the touchscreen assessment, while micronutrient intake from food were self-reported through multiple web-based 24 h recall diaries. The association between micronutrient intake or supplement use and z-LTL was assessed using multivariable linear regression models adjusting for demographic, lifestyle and clinical characteristics. RESULTS: About 50% (n = 131,810) of the participants, with complete data on all covariates, self-reported regular supplement intake. Whilst overall supplement intake was not associated with z-LTL, trends toward shorter z-LTL with regular vitamin B (-0.019 (95% CI: -0.041; 0.002)) and vitamin B9 (-0.027 (-0.054; 0.000)) supplement intake were observed. z-LTL was associated with food intake of pantothenic acid (-0.020 (-0.033; -0.007)), vitamin B6 (-0.015 (-0.027; -0.003)), biotin (0.010 (0.002; 0.018)) and folate (0.016 (0.003; 0.030)). Associations of z-LTL with these micronutrients were differentiated according to supplement intake. CONCLUSION: Negative associations equivalent to a year or less of age-related change in LTL between micronutrient intake and LTL were observed. Due to this small effect, the clinical importance of the associations and any relevance to the effects of vitamin and micronutrient intake toward chronic disease prevention remains uncertain.
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BACKGROUND: Heart failure with preserved ejection fraction (HFpEF) and atrial fibrillation (AF) frequently co-exist. There is a limited understanding on whether this coexistence is associated with distinct alterations in myocardial remodelling and mechanics. We aimed to determine if patients with atrial fibrillation (AF) and heart failure with preserved ejection fraction (HFpEF) represent a distinct phenotype. METHODS: In this secondary analysis of adults with HFpEF (NCT03050593), participants were comprehensively phenotyped with stress cardiac MRI, echocardiography and plasma fibroinflammatory biomarkers, and were followed for the composite endpoint (HF hospitalisation or death) at a median of 8.5 years. Those with AF were compared to sinus rhythm (SR) and unsupervised cluster analysis was performed to explore possible phenotypes. RESULTS: 136 subjects were included (SR = 75, AF = 61). The AF group was older (76 ± 8 vs. 70 ± 10 years) with less diabetes (36% vs. 61%) compared to the SR group and had higher left atrial (LA) volumes (61 ± 30 vs. 39 ± 15 mL/m2, p < 0.001), lower LA ejection fraction (EF) (31 ± 15 vs. 51 ± 12%, p < 0.001), worse left ventricular (LV) systolic function (LVEF 63 ± 8 vs. 68 ± 8%, p = 0.002; global longitudinal strain 13.6 ± 2.9 vs. 14.7 ± 2.4%, p = 0.003) but higher LV peak early diastolic strain rates (0.73 ± 0.28 vs. 0.53 ± 0.17 1/s, p < 0.001). The AF group had higher levels of syndecan-1, matrix metalloproteinase-2, proBNP, angiopoietin-2 and pentraxin-3, but lower level of interleukin-8. No difference in clinical outcomes was observed between the groups. Three distinct clusters were identified with the poorest outcomes (Log-rank p = 0.029) in cluster 2 (hypertensive and fibroinflammatory) which had equal representation of SR and AF. CONCLUSIONS: Presence of AF in HFpEF is associated with cardiac structural and functional changes together with altered expression of several fibro-inflammatory biomarkers. Distinct phenotypes exist in HFpEF which may have differing clinical outcomes.
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Fibrilação Atrial , Insuficiência Cardíaca , Imageamento por Ressonância Magnética Multiparamétrica , Humanos , Adulto , Volume Sistólico , Metaloproteinase 2 da Matriz , Função Ventricular Esquerda , Biomarcadores , Fenótipo , PrognósticoRESUMO
The life of RNA polymerase II (RNAPII) transcripts is shaped by the dynamic formation of mutually exclusive ribonucleoprotein complexes (RNPs) that direct transcript biogenesis and turnover. A key regulator of RNA metabolism in the nucleus is the scaffold protein ARS2 (arsenic resistance protein 2), bound to the cap binding complex (CBC). We report here that alternative splicing of ARS2's intron 5, generates cytoplasmic isoforms that lack 270 amino acids from the N-terminal of the protein and are functionally distinct from nuclear ARS2. Switching of ARS2 isoforms within the CBC in the cytoplasm has dramatic functional consequences, changing ARS2 from a NMD inhibitor to a NMD promoter that enhances the binding of UPF1 to NCBP1 and ERF1, favouring SURF complex formation, SMG7 recruitment and transcript degradation. ARS2 isoform exchange is also relevant during arsenic stress, where cytoplasmic ARS2 promotes a global response to arsenic in a CBC-independent manner. We propose that ARS2 isoform switching promotes the proper recruitment of RNP complexes during NMD and the cellular response to arsenic stress. The existence of non-redundant ARS2 isoforms is relevant for cell homeostasis, and stress response.
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Arsênio , Degradação do RNAm Mediada por Códon sem Sentido , Arsênio/metabolismo , Núcleo Celular/metabolismo , Degradação do RNAm Mediada por Códon sem Sentido/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Helicases/genética , RNA Polimerase II/genética , RNA Polimerase II/metabolismoRESUMO
PURPOSE: To quantify the impact of treatment planning system beam model parameters, based on the actual spread in radiotherapy community data, on clinical treatment plans and determine which complexity metrics best describe the impact beam modeling errors have on dose accuracy. METHODS: Ten beam modeling parameters for a Varian accelerator were modified in RayStation to match radiotherapy community data at the 2.5, 25, 50, 75, and 97.5 percentile levels. These modifications were evaluated on 25 patient cases, including prostate, non-small cell lung, H&N, brain, and mesothelioma, generating 1,000 plan perturbations. Differences in the mean planned dose to clinical target volumes (CTV) and organs at risk (OAR) were evaluated with respect to the planned dose using the reference (50th-percentile) parameter values. Correlation between CTV dose differences, and 18 different complexity metrics were evaluated using linear regression; R-squared values were used to determine the best metric. RESULTS: Perturbations to MLC offset and transmission parameters demonstrated the greatest changes in dose: up to 5.7% in CTVs and 16.7% for OARs. More complex clinical plans showed greater dose perturbation with atypical beam model parameters. The mean MLC Gap and Tongue & Groove index (TGi) complexity metrics best described the impact of TPS beam modeling variations on clinical dose delivery across all anatomical sites; similar, though not identical, trends between complexity and dose perturbation were observed among all sites. CONCLUSION: Extreme values for MLC offset and MLC transmission beam modeling parameters were found to most substantially impact the dose distribution of clinical plans and careful attention should be given to these beam modeling parameters. The mean MLC Gap and TGi complexity metrics were best suited to identifying clinical plans most sensitive to beam modeling errors; this could help provide focus for clinical QA in identifying unacceptable plans.
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Neoplasias , Órgãos em Risco , Aceleradores de Partículas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Órgãos em Risco/efeitos da radiação , Neoplasias/radioterapia , Aceleradores de Partículas/instrumentação , AlgoritmosRESUMO
CONTEXT: The COVID-19 pandemic highlighted the significance of public health laboratories across the United States, while also revealing weaknesses in the laboratory system. OBJECTIVE: To identify actionable recommendations for building a more resilient public health laboratory system based on previously published lessons learned from COVID-19. DESIGN, SETTING, AND PARTICIPANTS: In April 2023, the Association of Public Health Laboratories, in cooperation with RAND , convened a 1.5-day after action review workshop of approximately 30 public health laboratory stakeholders to reevaluate priorities, improve processes, and affect policies. MAIN OUTCOME MEASURES: Analysis of workshop discussions identified 5 priority areas and 19 recommendations related to clarifying laboratories' unique role and promoting workforce capacity/agility, technology, and collaboration with governmental and nongovernmental partners. RESULTS: Within the identified priority areas, workshop participants described how the recommendations would address challenges encountered during COVID-19 and contribute to strengthening the system. CONCLUSIONS: As the risk of novel infectious diseases persists and grows, the importance of maintaining laboratory response capabilities is likely to increase. Addressing the system's weaknesses will require active engagement of laboratories and the many stakeholders who depend on them, along with consistent, adequate funding to strengthen and sustain capabilities.
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COVID-19 , Laboratórios , Saúde Pública , SARS-CoV-2 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Humanos , Estados Unidos , Saúde Pública/métodos , Saúde Pública/tendências , Laboratórios/organização & administração , Laboratórios/normas , Pandemias/prevenção & controleRESUMO
BACKGROUND: Genome-wide association studies have identified many genetic loci that are robustly associated with coronary artery disease (CAD). However, the underlying biological mechanisms are still unknown for most of these loci, hindering the progress to medical translation. Evidence suggests that the genetic influence on CAD susceptibility may act partly through vascular smooth muscle cells (VSMCs). METHODS: We undertook genotyping, RNA sequencing, and cell behavior assays on a large bank of VSMCs (n>1499). Expression quantitative trait locus and splicing quantitative trait locus analyses were performed to identify genes with an expression that was influenced by CAD-associated variants. To identify candidate causal genes for CAD, we ascertained colocalizations of VSMC expression quantitative trait locus signals with CAD association signals by performing causal variants identification in associated regions analysis and the summary data-based mendelian randomization test. Druggability analysis was then performed on the candidate causal genes. CAD risk variants were tested for associations with VSMC proliferation, migration, and apoptosis. Collective effects of multiple CAD-associated variants on VSMC behavior were estimated by polygenic scores. RESULTS: Approximately 60% of the known CAD-associated variants showed statistically significant expression quantitative trait locus or splicing quantitative trait locus effects in VSMCs. Colocalization analyses identified 84 genes with expression quantitative trait locus signals that significantly colocalized with CAD association signals, identifying them as candidate causal genes. Druggability analysis indicated that 38 of the candidate causal genes were druggable, and 13 had evidence of drug-gene interactions. Of the CAD-associated variants tested, 139 showed suggestive associations with VSMC proliferation, migration, or apoptosis. A polygenic score model explained up to 5.94% of variation in several VSMC behavior parameters, consistent with polygenic influences on VSMC behavior. CONCLUSIONS: This comprehensive analysis shows that a large percentage of CAD loci can modulate gene expression in VSMCs and influence VSMC behavior. Several candidate causal genes identified are likely to be druggable and thus represent potential therapeutic targets.
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Doença da Artéria Coronariana , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/metabolismo , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Polimorfismo de Nucleotídeo Único , Locos de Características QuantitativasRESUMO
Conventional nuclear magnetic resonance (NMR) enables detection of chemicals and their transformations by exciting nuclear spin ensembles with a radio-frequency pulse followed by detection of the precessing spins at their characteristic frequencies. The detected frequencies report on chemical reactions in real time and the signal amplitudes scale with concentrations of products and reactants. Here, we employ Radiofrequency Amplification by Stimulated Emission of Radiation (RASER), a quantum phenomenon producing coherent emission of 13C signals, to detect chemical transformations. The 13C signals are emitted by the negatively hyperpolarized biomolecules without external radio frequency pulses and without any background signal from other, nonhyperpolarized spins in the ensemble. Here, we studied the hydrolysis of hyperpolarized ethyl-[1-13C]acetate to hyperpolarized [1-13C]acetate, which was analyzed as a model system by conventional NMR and 13C RASER. The chemical transformation of 13C RASER-active species leads to complete and abrupt disappearance of reactant signals and delayed, abrupt reappearance of a frequency-shifted RASER signal without destroying 13C polarization. The experimentally observed "quantum" RASER threshold is supported by simulations.
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BACKGROUND: Out-of-hospital cardiac arrest (OHCA) affects over 300,000 individuals per year in the United States with poor survival rates overall. A remarkable 5-fold difference in survival-to-hospital discharge rates exist across United States communities. METHODS: We conducted a study using qualitative research methods comparing the system of care across sites in Michigan communities with varying OHCA survival outcomes, as measured by return to spontaneous circulation with pulse upon emergency department arrival. RESULTS: Major themes distinguishing higher performing sites were (1) working as a team, (2) devoting resources to coordination across agencies, and (3) developing a continuous quality improvement culture. These themes spanned the chain of survival framework for OHCA. By examining the unique processes, procedures, and characteristics of higher- relative to lower-performing sites, we gleaned lessons learned that appear to distinguish higher performers. The higher performing sites reported being the most collaborative, due in part to facilitation of system integration by progressive leadership that is willing to build bridges among stakeholders. CONCLUSIONS: Based on the distinguishing features of higher performing sites, we provide recommendations for toolkit development to improve survival in prehospital systems of care for OHCA.