Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 159
Filtrar
1.
Cell ; 184(5): 1171-1187.e20, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33621484

RESUMO

SARS-CoV-2 can mutate and evade immunity, with consequences for efficacy of emerging vaccines and antibody therapeutics. Here, we demonstrate that the immunodominant SARS-CoV-2 spike (S) receptor binding motif (RBM) is a highly variable region of S and provide epidemiological, clinical, and molecular characterization of a prevalent, sentinel RBM mutation, N439K. We demonstrate N439K S protein has enhanced binding affinity to the hACE2 receptor, and N439K viruses have similar in vitro replication fitness and cause infections with similar clinical outcomes as compared to wild type. We show the N439K mutation confers resistance against several neutralizing monoclonal antibodies, including one authorized for emergency use by the US Food and Drug Administration (FDA), and reduces the activity of some polyclonal sera from persons recovered from infection. Immune evasion mutations that maintain virulence and fitness such as N439K can emerge within SARS-CoV-2 S, highlighting the need for ongoing molecular surveillance to guide development and usage of vaccines and therapeutics.


Assuntos
COVID-19/imunologia , Aptidão Genética , Evasão da Resposta Imune , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Enzima de Conversão de Angiotensina 2/química , Anticorpos Neutralizantes/genética , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/virologia , Humanos , Mutação , Filogenia , SARS-CoV-2/química , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/química , Virulência
2.
Nat Immunol ; 23(1): 40-49, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34937928

RESUMO

SARS-CoV-2 infection is generally mild or asymptomatic in children but a biological basis for this outcome is unclear. Here we compare antibody and cellular immunity in children (aged 3-11 years) and adults. Antibody responses against spike protein were high in children and seroconversion boosted responses against seasonal Beta-coronaviruses through cross-recognition of the S2 domain. Neutralization of viral variants was comparable between children and adults. Spike-specific T cell responses were more than twice as high in children and were also detected in many seronegative children, indicating pre-existing cross-reactive responses to seasonal coronaviruses. Importantly, children retained antibody and cellular responses 6 months after infection, whereas relative waning occurred in adults. Spike-specific responses were also broadly stable beyond 12 months. Therefore, children generate robust, cross-reactive and sustained immune responses to SARS-CoV-2 with focused specificity for the spike protein. These findings provide insight into the relative clinical protection that occurs in most children and might help to guide the design of pediatric vaccination regimens.


Assuntos
Anticorpos Antivirais/imunologia , Coronavirus Humano 229E/imunologia , Coronavirus Humano OC43/imunologia , Proteção Cruzada/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Imunidade Adaptativa/imunologia , Adulto , Anticorpos Neutralizantes/imunologia , COVID-19/imunologia , Vacinas contra COVID-19/imunologia , Criança , Pré-Escolar , Reações Cruzadas/imunologia , Humanos
3.
Nature ; 619(7969): 338-347, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37380775

RESUMO

Spillover events of avian influenza A viruses (IAVs) to humans could represent the first step in a future pandemic1. Several factors that limit the transmission and replication of avian IAVs in mammals have been identified. There are several gaps in our understanding to predict which virus lineages are more likely to cross the species barrier and cause disease in humans1. Here, we identified human BTN3A3 (butyrophilin subfamily 3 member A3)2 as a potent inhibitor of avian IAVs but not human IAVs. We determined that BTN3A3 is expressed in human airways and its antiviral activity evolved in primates. We show that BTN3A3 restriction acts primarily at the early stages of the virus life cycle by inhibiting avian IAV RNA replication. We identified residue 313 in the viral nucleoprotein (NP) as the genetic determinant of BTN3A3 sensitivity (313F or, rarely, 313L in avian viruses) or evasion (313Y or 313V in human viruses). However, avian IAV serotypes, such as H7 and H9, that spilled over into humans also evade BTN3A3 restriction. In these cases, BTN3A3 evasion is due to substitutions (N, H or Q) in NP residue 52 that is adjacent to residue 313 in the NP structure3. Thus, sensitivity or resistance to BTN3A3 is another factor to consider in the risk assessment of the zoonotic potential of avian influenza viruses.


Assuntos
Aves , Interações entre Hospedeiro e Microrganismos , Vírus da Influenza A , Influenza Aviária , Influenza Humana , Zoonoses Virais , Animais , Humanos , Aves/virologia , Vírus da Influenza A/classificação , Vírus da Influenza A/genética , Vírus da Influenza A/crescimento & desenvolvimento , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/transmissão , Influenza Aviária/virologia , Influenza Humana/prevenção & controle , Influenza Humana/transmissão , Influenza Humana/virologia , Primatas , Sistema Respiratório/metabolismo , Sistema Respiratório/virologia , Medição de Risco , Zoonoses Virais/prevenção & controle , Zoonoses Virais/transmissão , Zoonoses Virais/virologia , Replicação Viral
4.
Nature ; 617(7961): 555-563, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36996873

RESUMO

An outbreak of acute hepatitis of unknown aetiology in children was reported in Scotland1 in April 2022 and has now been identified in 35 countries2. Several recent studies have suggested an association with human adenovirus with this outbreak, a virus not commonly associated with hepatitis. Here we report a detailed case-control investigation and find an association between adeno-associated virus 2 (AAV2) infection and host genetics in disease susceptibility. Using next-generation sequencing, PCR with reverse transcription, serology and in situ hybridization, we detected recent infection with AAV2 in plasma and liver samples in 26 out of 32 (81%) cases of hepatitis compared with 5 out of 74 (7%) of samples from unaffected individuals. Furthermore, AAV2 was detected within ballooned hepatocytes alongside a prominent T cell infiltrate in liver biopsy samples. In keeping with a CD4+ T-cell-mediated immune pathology, the human leukocyte antigen (HLA) class II HLA-DRB1*04:01 allele was identified in 25 out of 27 cases (93%) compared with a background frequency of 10 out of 64 (16%; P = 5.49 × 10-12). In summary, we report an outbreak of acute paediatric hepatitis associated with AAV2 infection (most likely acquired as a co-infection with human adenovirus that is usually required as a 'helper virus' to support AAV2 replication) and disease susceptibility related to HLA class II status.


Assuntos
Infecções por Adenovirus Humanos , Dependovirus , Hepatite , Criança , Humanos , Doença Aguda/epidemiologia , Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/genética , Infecções por Adenovirus Humanos/virologia , Alelos , Estudos de Casos e Controles , Linfócitos T CD4-Positivos/imunologia , Coinfecção/epidemiologia , Coinfecção/virologia , Dependovirus/isolamento & purificação , Predisposição Genética para Doença , Vírus Auxiliares/isolamento & purificação , Hepatite/epidemiologia , Hepatite/genética , Hepatite/virologia , Hepatócitos/virologia , Cadeias HLA-DRB1/genética , Cadeias HLA-DRB1/imunologia , Fígado/virologia
5.
Nature ; 596(7872): 417-422, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34192737

RESUMO

Although two-dose mRNA vaccination provides excellent protection against SARS-CoV-2, there is little information about vaccine efficacy against variants of concern (VOC) in individuals above eighty years of age1. Here we analysed immune responses following vaccination with the BNT162b2 mRNA vaccine2 in elderly participants and younger healthcare workers. Serum neutralization and levels of binding IgG or IgA after the first vaccine dose were lower in older individuals, with a marked drop in participants over eighty years old. Sera from participants above eighty showed lower neutralization potency against the B.1.1.7 (Alpha), B.1.351 (Beta) and P.1. (Gamma) VOC than against the wild-type virus and were more likely to lack any neutralization against VOC following the first dose. However, following the second dose, neutralization against VOC was detectable regardless of age. The frequency of SARS-CoV-2 spike-specific memory B cells was higher in elderly responders (whose serum showed neutralization activity) than in non-responders after the first dose. Elderly participants showed a clear reduction in somatic hypermutation of class-switched cells. The production of interferon-γ and interleukin-2 by SARS-CoV-2 spike-specific T cells was lower in older participants, and both cytokines were secreted primarily by CD4 T cells. We conclude that the elderly are a high-risk population and that specific measures to boost vaccine responses in this population are warranted, particularly where variants of concern are circulating.


Assuntos
Envelhecimento/imunologia , Vacinas contra COVID-19/imunologia , Imunidade , SARS-CoV-2/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/sangue , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Autoanticorpos/imunologia , Linfócitos B/citologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Vacina BNT162 , Vacinas contra COVID-19/administração & dosagem , Feminino , Pessoal de Saúde , Humanos , Imunidade/genética , Imunização Secundária , Imunoglobulina A/imunologia , Switching de Imunoglobulina , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Memória Imunológica/imunologia , Inflamação/sangue , Inflamação/imunologia , Interferon gama/imunologia , Interleucina-2/imunologia , Masculino , Pessoa de Meia-Idade , Hipermutação Somática de Imunoglobulina , Glicoproteína da Espícula de Coronavírus/imunologia , Linfócitos T/imunologia , Vacinação , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia , Vacinas de mRNA
6.
J Gen Virol ; 105(6)2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38861287

RESUMO

Increased human-to-human transmission of monkeypox virus (MPXV) is cause for concern, and antibodies directed against vaccinia virus (VACV) are known to confer cross-protection against Mpox. We used 430 serum samples derived from the Scottish patient population to investigate antibody-mediated cross-neutralization against MPXV. By combining electrochemiluminescence immunoassays with live-virus neutralization assays, we show that people born when smallpox vaccination was routinely offered in the United Kingdom have increased levels of antibodies that cross-neutralize MPXV. Our results suggest that age is a risk factor of Mpox infection, and people born after 1971 are at higher risk of infection upon exposure.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Monkeypox virus , Mpox , Vacina Antivariólica , Humanos , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Vacina Antivariólica/imunologia , Vacina Antivariólica/administração & dosagem , Adulto , Pessoa de Meia-Idade , Monkeypox virus/imunologia , Adulto Jovem , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Mpox/imunologia , Mpox/prevenção & controle , Feminino , Adolescente , Idoso , Masculino , Proteção Cruzada/imunologia , Escócia , Fatores Etários , Testes de Neutralização , Criança , Vacinação , Varíola/prevenção & controle , Varíola/imunologia , Pré-Escolar , Reações Cruzadas , Idoso de 80 Anos ou mais
7.
Genome Res ; 31(4): 645-658, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33722935

RESUMO

We have developed periscope, a tool for the detection and quantification of subgenomic RNA (sgRNA) in SARS-CoV-2 genomic sequence data. The translation of the SARS-CoV-2 RNA genome for most open reading frames (ORFs) occurs via RNA intermediates termed "subgenomic RNAs." sgRNAs are produced through discontinuous transcription, which relies on homology between transcription regulatory sequences (TRS-B) upstream of the ORF start codons and that of the TRS-L, which is located in the 5' UTR. TRS-L is immediately preceded by a leader sequence. This leader sequence is therefore found at the 5' end of all sgRNA. We applied periscope to 1155 SARS-CoV-2 genomes from Sheffield, United Kingdom, and validated our findings using orthogonal data sets and in vitro cell systems. By using a simple local alignment to detect reads that contain the leader sequence, we were able to identify and quantify reads arising from canonical and noncanonical sgRNA. We were able to detect all canonical sgRNAs at the expected abundances, with the exception of ORF10. A number of recurrent noncanonical sgRNAs are detected. We show that the results are reproducible using technical replicates and determine the optimum number of reads for sgRNA analysis. In VeroE6 ACE2+/- cell lines, periscope can detect the changes in the kinetics of sgRNA in orthogonal sequencing data sets. Finally, variants found in genomic RNA are transmitted to sgRNAs with high fidelity in most cases. This tool can be applied to all sequenced COVID-19 samples worldwide to provide comprehensive analysis of SARS-CoV-2 sgRNA.


Assuntos
Genoma Viral , RNA Viral/genética , SARS-CoV-2/genética , Análise de Sequência de RNA/métodos , Animais , Sequência de Bases , Chlorocebus aethiops , Humanos , Limite de Detecção , Células Vero
8.
Blood ; 139(11): 1694-1706, 2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-34995355

RESUMO

In acute myeloid leukemia (AML), measurable residual disease (MRD) before or after allogeneic hematopoietic cell transplantation (HCT) is an established independent indicator of poor outcome. To address how peri-HCT MRD dynamics could refine risk assessment across different conditioning intensities, we analyzed 810 adults transplanted in first or second remission after myeloablative conditioning (MAC; n = 515) or non-MAC (n = 295) who underwent multiparameter flow cytometry-based MRD testing before as well as 20 to 40 days after allografting. Patients without pre- and post-HCT MRD (MRDneg/MRDneg) had the lowest risks of relapse and highest relapse-free survival (RFS) and overall survival (OS). Relative to those patients, outcomes for MRDpos/MRDpos and MRDneg/MRDpos patients were poor regardless of conditioning intensity. Outcomes for MRDpos/MRDneg patients were intermediate. Among 161 patients with MRD before HCT, MRD was cleared more commonly with a MAC (85 of 104; 81.7%) than non-MAC (33 of 57; 57.9%) regimen (P = .002). Although non-MAC regimens were less likely to clear MRD, if they did, the impact on outcome was greater. Thus, there was a significant interaction between conditioning intensity and "MRD conversion" for relapse (P = .020), RFS (P = .002), and OS (P = .001). Similar findings were obtained in the subset of 590 patients receiving HLA-matched allografts. C-statistic values were higher (indicating higher predictive accuracy) for peri-HCT MRD dynamics compared with the isolated use of pre-HCT MRD status or post-HCT MRD status for prediction of relapse, RFS, and OS. Across conditioning intensities, peri-HCT MRD dynamics improve risk assessment over isolated pre- or post-HCT MRD assessments in patients with AML.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Adulto , Citometria de Fluxo , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/etiologia , Leucemia Mieloide Aguda/terapia , Neoplasia Residual/etiologia , Estudos Retrospectivos , Condicionamento Pré-Transplante
9.
PLoS Biol ; 19(12): e3001065, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34932557

RESUMO

The pandemic spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the etiological agent of Coronavirus Disease 2019 (COVID-19), represents an ongoing international health crisis. A key symptom of SARS-CoV-2 infection is the onset of fever, with a hyperthermic temperature range of 38 to 41°C. Fever is an evolutionarily conserved host response to microbial infection that can influence the outcome of viral pathogenicity and regulation of host innate and adaptive immune responses. However, it remains to be determined what effect elevated temperature has on SARS-CoV-2 replication. Utilizing a three-dimensional (3D) air-liquid interface (ALI) model that closely mimics the natural tissue physiology of SARS-CoV-2 infection in the respiratory airway, we identify tissue temperature to play an important role in the regulation of SARS-CoV-2 infection. Respiratory tissue incubated at 40°C remained permissive to SARS-CoV-2 entry but refractory to viral transcription, leading to significantly reduced levels of viral RNA replication and apical shedding of infectious virus. We identify tissue temperature to play an important role in the differential regulation of epithelial host responses to SARS-CoV-2 infection that impact upon multiple pathways, including intracellular immune regulation, without disruption to general transcription or epithelium integrity. We present the first evidence that febrile temperatures associated with COVID-19 inhibit SARS-CoV-2 replication in respiratory epithelia. Our data identify an important role for tissue temperature in the epithelial restriction of SARS-CoV-2 independently of canonical interferon (IFN)-mediated antiviral immune defenses.


Assuntos
Células Epiteliais/imunologia , Temperatura Alta , Imunidade Inata/imunologia , Interferons/imunologia , Mucosa Respiratória/imunologia , SARS-CoV-2/imunologia , Replicação Viral/imunologia , Adolescente , Animais , COVID-19/genética , COVID-19/imunologia , COVID-19/virologia , Chlorocebus aethiops , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Feminino , Perfilação da Expressão Gênica/métodos , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata/genética , Interferons/genética , Interferons/metabolismo , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , RNA-Seq/métodos , Mucosa Respiratória/metabolismo , Mucosa Respiratória/virologia , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Técnicas de Cultura de Tecidos , Células Vero , Replicação Viral/genética , Replicação Viral/fisiologia
10.
PLoS Biol ; 19(2): e3001091, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33630831

RESUMO

The recent emergence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the underlying cause of Coronavirus Disease 2019 (COVID-19), has led to a worldwide pandemic causing substantial morbidity, mortality, and economic devastation. In response, many laboratories have redirected attention to SARS-CoV-2, meaning there is an urgent need for tools that can be used in laboratories unaccustomed to working with coronaviruses. Here we report a range of tools for SARS-CoV-2 research. First, we describe a facile single plasmid SARS-CoV-2 reverse genetics system that is simple to genetically manipulate and can be used to rescue infectious virus through transient transfection (without in vitro transcription or additional expression plasmids). The rescue system is accompanied by our panel of SARS-CoV-2 antibodies (against nearly every viral protein), SARS-CoV-2 clinical isolates, and SARS-CoV-2 permissive cell lines, which are all openly available to the scientific community. Using these tools, we demonstrate here that the controversial ORF10 protein is expressed in infected cells. Furthermore, we show that the promising repurposed antiviral activity of apilimod is dependent on TMPRSS2 expression. Altogether, our SARS-CoV-2 toolkit, which can be directly accessed via our website at https://mrcppu-covid.bio/, constitutes a resource with considerable potential to advance COVID-19 vaccine design, drug testing, and discovery science.


Assuntos
Vacinas contra COVID-19 , COVID-19/diagnóstico , COVID-19/virologia , Genética Reversa , SARS-CoV-2/genética , Células A549 , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Chlorocebus aethiops , Códon , Humanos , Hidrazonas/farmacologia , Camundongos , Morfolinas/farmacologia , Fases de Leitura Aberta , Plasmídeos/genética , Pirimidinas/farmacologia , Serina Endopeptidases/metabolismo , Células Vero , Proteínas Virais/metabolismo
11.
Eur J Haematol ; 112(1): 111-121, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37526606

RESUMO

BACKGROUND: Bone marrow (BM) assessment after CAR-T cell immunotherapy infusion is not routinely performed to monitor adverse events such as cytopenias, hemophagocytic lymphohistiocytosis, or infections. Our institution has performed BM biopsies as part of CAR-T cell treatment protocols, encompassing pre- and post-treatment time points and during long-term follow-up. METHODS: We conducted a systematic retrospective review of BM abnormalities observed in samples from 259 patients following CAR-T cell immunotherapy. We correlated BM pathology findings with mortality, relapse/residual disease, and laboratory values. RESULTS: At a median of 35.5 days post-CAR-T infusion, 25.5% showed severe marrow hypocellularity, and 6.2% showed serous atrophy, and peripheral blood cytopenias corroborated these observations. Marrow features associated with reduced disease burden post-CAR-T infusion include increased lymphocytes seen in 16 patients and an increase of macrophages or granulomatous response seen in 25 patients. However, a 100-day landmark analysis also showed increased marrow histiocytes were associated with lower survival (median OS 6.0 vs. 21.4 months, p = .026), as was grade 2-3 marrow reticulin (18 patients) (median OS 12.5 vs. 24.2 months, p = .034). CONCLUSIONS: These data represent the first systematic observations of BM changes in patients receiving CAR-T cell immunotherapy.


Assuntos
Citopenia , Receptores de Antígenos Quiméricos , Humanos , Receptores de Antígenos Quiméricos/genética , Medula Óssea , Recidiva Local de Neoplasia , Imunoterapia , Imunoterapia Adotiva/efeitos adversos , Terapia Baseada em Transplante de Células e Tecidos , Antígenos CD19
12.
PLoS Pathog ; 17(12): e1010022, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34855916

RESUMO

Vaccines are proving to be highly effective in controlling hospitalisation and deaths associated with SARS-CoV-2 infection but the emergence of viral variants with novel antigenic profiles threatens to diminish their efficacy. Assessment of the ability of sera from vaccine recipients to neutralise SARS-CoV-2 variants will inform the success of strategies for minimising COVID19 cases and the design of effective antigenic formulations. Here, we examine the sensitivity of variants of concern (VOCs) representative of the B.1.617.1 and B.1.617.2 (first associated with infections in India) and B.1.351 (first associated with infection in South Africa) lineages of SARS-CoV-2 to neutralisation by sera from individuals vaccinated with the BNT162b2 (Pfizer/BioNTech) and ChAdOx1 (Oxford/AstraZeneca) vaccines. Across all vaccinated individuals, the spike glycoproteins from B.1.617.1 and B.1.617.2 conferred reductions in neutralisation of 4.31 and 5.11-fold respectively. The reduction seen with the B.1.617.2 lineage approached that conferred by the glycoprotein from B.1.351 (South African) variant (6.29-fold reduction) that is known to be associated with reduced vaccine efficacy. Neutralising antibody titres elicited by vaccination with two doses of BNT162b2 were significantly higher than those elicited by vaccination with two doses of ChAdOx1. Fold decreases in the magnitude of neutralisation titre following two doses of BNT162b2, conferred reductions in titre of 7.77, 11.30 and 9.56-fold respectively to B.1.617.1, B.1.617.2 and B.1.351 pseudoviruses, the reduction in neutralisation of the delta variant B.1.617.2 surpassing that of B.1.351. Fold changes in those vaccinated with two doses of ChAdOx1 were 0.69, 4.01 and 1.48 respectively. The accumulation of mutations in these VOCs, and others, demonstrate the quantifiable risk of antigenic drift and subsequent reduction in vaccine efficacy. Accordingly, booster vaccines based on updated variants are likely to be required over time to prevent productive infection. This study also suggests that two dose regimes of vaccine are required for maximal BNT162b2 and ChAdOx1-induced immunity.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacina BNT162 , COVID-19 , Imunização Secundária , SARS-CoV-2/imunologia , Eficácia de Vacinas , Deriva e Deslocamento Antigênicos/imunologia , Vacina BNT162/administração & dosagem , Vacina BNT162/imunologia , COVID-19/imunologia , COVID-19/mortalidade , COVID-19/prevenção & controle , Células HEK293 , Humanos
13.
Epidemiol Infect ; 151: e59, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36915219

RESUMO

Despite promising steps towards the elimination of hepatitis C virus (HCV) in the UK, several indicators provide a cause for concern for future disease burden. We aimed to improve understanding of geographical variation in HCV-related severe liver disease and historic risk factor prevalence among clinic attendees in England and Scotland. We used metadata from 3829 HCV-positive patients consecutively enrolled into HCV Research UK from 48 hospital centres in England and Scotland during 2012-2014. Employing mixed-effects statistical modelling, several independent risk factors were identified: age 46-59 y (ORadj 3.06) and ≥60 y (ORadj 5.64) relative to <46 y, male relative to female sex (ORadj 1.58), high BMI (ORadj 1.73) and obesity (ORadj 2.81) relative to normal BMI, diabetes relative to no diabetes (ORadj 2.75), infection with HCV genotype (GT)-3 relative to GT-1 (ORadj 1.75), route of infection through blood products relative to injecting drug use (ORadj 1.40), and lower odds were associated with black ethnicity (ORadj 0.31) relative to white ethnicity. A small proportion of unexplained variation was attributed to differences between hospital centres and local health authorities. Our study provides a baseline measure of historic risk factor prevalence and potential geographical variation in healthcare provision, to support ongoing monitoring of HCV-related disease burden and the design of risk prevention measures.


Assuntos
Hepacivirus , Hepatite C , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Transversais , Hepatite C/complicações , Hepatite C/epidemiologia , Prevalência , Fatores de Risco , Escócia/epidemiologia , Adulto , Idoso
14.
Behav Res Methods ; 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38017201

RESUMO

We present a Cantonese emotional speech dataset that is suitable for use in research investigating the auditory and visual expression of emotion in tonal languages. This unique dataset consists of auditory and visual recordings of ten native speakers of Cantonese uttering 50 sentences each in the six basic emotions plus neutral (angry, happy, sad, surprise, fear, and disgust). The visual recordings have a full HD resolution of 1920 × 1080 pixels and were recorded at 50 fps. The important features of the dataset are outlined along with the factors considered when compiling the dataset. A validation study of the recorded emotion expressions was conducted in which 15 native Cantonese perceivers completed a forced-choice emotion identification task. The variability of the speakers and the sentences was examined by testing the degree of concordance between the intended and the perceived emotion. We compared these results with those of other emotion perception and evaluation studies that have tested spoken emotions in languages other than Cantonese. The dataset is freely available for research purposes.

15.
J Viral Hepat ; 29(4): 252-262, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35075742

RESUMO

Hepatitis C virus (HCV) is a leading cause of liver disease worldwide. There are no previous representative community HCV prevalence studies from Southern Africa, and limited genotypic data. Epidemiological data are required to inform an effective public health response. We conducted a household census-based random sampling serological survey, and a prospective hospital-based study of patients with cirrhosis and hepatocellular carcinoma (HCC) in Blantyre, Malawi. We tested participants with an HCV antigen/antibody ELISA (Monolisa, Bio-Rad), confirmed with PCR (GeneXpert, Cepheid) and used line immunoassay (Inno-LIA, Fujiribio) for RNA-negative participants. We did target-enrichment whole-genome HCV sequencing (NextSeq, Illumina). Among 96,386 censused individuals, we randomly selected 1661 people aged ≥16 years. Population-standardized HCV RNA prevalence was 0.2% (95% CI 0.1-0.5). Among 236 patients with cirrhosis and HCC, HCV RNA prevalence was 1.9% and 5.0%, respectively. Mapping showed that HCV RNA+ patients were from peri-urban areas surrounding Blantyre. Community and hospital HCV RNA+ participants were older than comparator HCV RNA-negative populations (median 53 vs 30 years for community, p = 0.01 and 68 vs 40 years for cirrhosis/HCC, p < 0.001). Endemic HCV genotypes (n = 10) were 4v (50%), 4r (30%) and 4w (10%). In this first census-based community serological study in Southern Africa, HCV was uncommon in the general population, was centred on peri-urban regions and was attributable for <5% of liver disease. HCV infection was observed only among older people, suggesting a historic mechanism of transmission. Genotype 4r, which has been associated with treatment failure with ledipasvir and daclatasvir, is endemic.


Assuntos
Carcinoma Hepatocelular , Hepatite C , Neoplasias Hepáticas , Adolescente , Adulto , Idoso , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/epidemiologia , Hepacivirus/genética , Hepatite C/complicações , Hepatite C/epidemiologia , Anticorpos Anti-Hepatite C , Humanos , Cirrose Hepática/complicações , Neoplasias Hepáticas/complicações , Malaui/epidemiologia , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , RNA
16.
Am J Hematol ; 97(6): 740-748, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35266218

RESUMO

In patients undergoing hematopoietic cell transplantation (HCT), venous thromboembolism (VTE) remains a serious complication that lacks validated risk assessment models (RAMs) to guide thromboprophylaxis. To address this dilemma, we performed a temporal and external validation study of the recently derived HIGH-2-LOW RAM. We selected adult patients undergoing allogeneic HCT from Fred Hutchinson Cancer Research Center (FHCRC) and MD Anderson Cancer Center (MDACC). Patients who died, received anticoagulation, or did not engraft platelets by day 30 were excluded. Primary outcomes were defined as overall VTE and pulmonary embolism ± lower-extremity deep venous thromboembolism (PE/LE-DVT) by day 180. Covariates were weighted according to the original model, except that grade 2-4 GVHD was substituted for grade 3-4. Discrimination and calibration were assessed. A total of 765 patients from FHCRC and 954 patients from MDACC were included. Incident VTE by day 180 was 5.1% at FHCRC and 6.8% at MDACC. The HIGH-2-LOW score had a c-statistic of 0.67 (0.59-0.75) for VTE and 0.75 (0.64-0.81) for PE/LE-DVT at FHCRC and 0.62 (0.55-0.70) for VTE and 0.70 (0.56-0.83) for PE/LE-DVT at MDACC. Twenty-five percent and 23% of patients were classified as high risk (2+ points) in the two cohorts, respectively. High versus low-risk was associated with odds ratio (OR) of 2.80 (1.46-5.38) for VTE and 4.21 (1.82-9.77) for PE/LE-DVT at FHCRC and OR of 3.54 (2.12-5.91) for VTE and 6.82 (2.30-20.16) for PE-LE-DVT at MDACC. The HIGH-2-LOW RAM identified allogeneic HCT recipients at high risk for VTE in both validation cohorts. It can improve evidence-based decision-making for thromboprophylaxis post-transplant.


Assuntos
Embolia Pulmonar , Tromboembolia Venosa , Anticoagulantes/uso terapêutico , Humanos , Embolia Pulmonar/induzido quimicamente , Fatores de Risco , Transplante Homólogo/efeitos adversos , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia
17.
Exp Brain Res ; 240(1): 249-261, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34727219

RESUMO

Visual-spatial selective attention enhances the processing of task-relevant visual events while suppressing the processing of irrelevant ones. In this study, we employed a frequency-tagging paradigm to investigate how sustained visual-spatial attention modulates the first harmonic and second harmonic steady-state visual evoked potentials (SSVEPs). Unlike previous studies, that investigated stimulation durations of 10 s or less, we tested a 30-s period. SSVEPs were elicited by simultaneously presenting to the right and left visual hemifields two pattern reversal checkerboard stimuli modulating at 7.14 Hz and 11.11 Hz. Participants were cued to selectively attend to one visual hemifield while ignoring the other. Behavioral results indicated that participants selectively attended to the cued visual hemifield. When participants attended to the visual stimuli, there were larger second harmonic SSVEPs but no attentional modulation of first harmonics. The results are consistent with the proposal that neural populations underlying first, and second harmonics have distinct functional roles, i.e., first harmonics' mechanisms preserve stimulus properties and are resistant to attentional gain, whereas second harmonics mediate attentional modulation. This interpretation is supported by a gain control theory of selective attention.


Assuntos
Eletroencefalografia , Potenciais Evocados Visuais , Atenção , Sinais (Psicologia) , Potenciais Evocados , Humanos , Estimulação Luminosa
18.
Cogn Emot ; 36(8): 1576-1593, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36300438

RESUMO

In higher-level cognitive tasks, older compared to younger adults show a bias towards positive emotion information and away from negative information (a positivity effect). It is unclear whether this effect occurs in early perceptual processing. This issue is important for determining if the positivity effect is due to automatic rather than controlled processing. We tested this with older and younger adults on a positive/negative face emotion valence classification task using masked priming. Positive (happy) and negative (angry) face targets were preceded by masked repetition or valence primes with neutral face baselines. In Experiment 1, 30 younger and 30 older adults were tested with 50 ms primes. Younger adults showed repetition priming for both positive and negative targets. Older adults showed repetition priming for positive but not negative targets. Neither group showed valence priming. In Experiment 2, 30 older and 29 younger adults were tested with longer duration primes. Younger adults showed repetition priming for both positive and negative emotions, and no valence priming. Older adults only showed repetition and valence priming for positive targets. We proposed older adults' lack of angry face priming was due to an early attention orienting strategy favouring happy expressions at the expense of angry ones.


Assuntos
Ira , Emoções , Humanos , Idoso , Felicidade , Atenção , Priming de Repetição , Expressão Facial
19.
Qual Health Res ; 32(13): 1952-1964, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36315098

RESUMO

This research developed from a co-produced project called Moving Social Work. The purpose of this ongoing project is to train social workers in how to promote physical activity for and to disabled people. The first stage of the project consisted of building evidence to design a training programme prototype. As part of this stage, a Delphi study was conducted to ask leading experts about what should be included in the prototype. Questionnaires were sent to participants until consensus was reached. In reflecting on the results, people involved in the study commented that there was more about the experts' opinions than percentages of agreement. Our co-production partners resolved that the Delphi was insufficient and called for detailed conversations with the experts. In response to this call, follow-up interviews with 10 experts who participated in the final questionnaire round of the Delphi were carried out. The interviews were co-produced, dyadic and data prompted. Dialogical inquiry was used to frame and co-analyse data. The results illuminate the capacity of qualitative research to justify, rectify, complicate, clarify, concretize, expand and question consensus-based evidence. The implications of the results for Moving Social Work are discussed. Beyond the empirical border of the project, wider contributions to literature are presented. As part of these, two key statements are highlighted and warranted: dialogical inquiry supports the practice of co-produced research, and Delphi studies should be followed by a Big Q qualitative study.


Assuntos
Exercício Físico , Humanos , Técnica Delphi , Consenso , Pesquisa Qualitativa , Inquéritos e Questionários
20.
Am J Hematol ; 96(9): 1137-1146, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34097772

RESUMO

History of venous thromboembolism (VTE) is prevalent among patients undergoing hematopoietic cell transplantation (HCT). Management of anticoagulation is particularly challenging as most patients will have chemotherapy-induced thrombocytopenia while awaiting engraftment post-HCT. We conducted a retrospective study of autologous and allogeneic HCT recipients with prior VTE from 2006-2015 to 1) compare anticoagulant strategies on short-term VTE recurrence and bleeding and 2) assess predictors for VTE recurrence beyond 30 days. Patients with VTE were allocated to two cohorts based on anticoagulant strategy at thrombocytopenia onset and underwent inverse probability weighting to assess primary outcomes of VTE recurrence and bleeding within 30 days post-HCT. Subsequently, multivariable logistic regression model was used to assess the association of 100-day VTE recurrence by the HIGH-2-LOW VTE risk assessment score and whether patients resumed anticoagulation at platelet recovery. Thirteen percent of recipients had VTE prior to HCT; of those meeting inclusion criteria, 227 continued anticoagulation and 113 temporarily discontinued it. Anticoagulant strategy was not significantly associated with decreased risk of VTE recurrence within 30 days (3% vs 4%, p = 0.61); however, risk of overall bleeding was non-significantly higher in those who continued vs discontinued anticoagulation (41% vs 31%, p = 0.08). In a subgroup of 250 allogeneic HCT patients, every one-point increase of HIGH-2-LOW score was significantly associated with VTE recurrence at 100 days (OR 1.57 [95% CI 1.10-2.23]), while anticoagulation resumption upon platelet engraftment was associated with lower recurrent risk (OR 0.48 [0.20-1.14]). Temporarily withholding anticoagulation during thrombocytopenia may optimize risk-benefit tradeoffs, though additional strategies are essential to prevent VTE recurrence after hematopoietic recovery.


Assuntos
Anticoagulantes/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Hemorragia/induzido quimicamente , Tromboembolia Venosa/prevenção & controle , Adulto , Idoso , Anticoagulantes/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Fatores de Risco , Prevenção Secundária , Tromboembolia Venosa/etiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA