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INTRODUCTION: Hearing loss is a chronic health condition that rises sharply with age. The way people respond to and cope with health conditions is influenced by their capacity to perform illness and treatment-related work. The aim was to explore the cumulative burdens of living with hearing loss and the resources mobilised to ease the burdens. METHODS: A qualitative design was used with semi-structured interviews (online or in-person) with participants recruited through audiology services and nonclinical services, such as lip-reading classes. Forty-six participants with hearing loss aged between 16 and 96 years were interviewed. An abductive approach, informed by May et al.'s burden of treatment theory, was used to analyse the data. RESULTS: The illness burden involved participants working to make sense of their hearing loss, engaging in emotional work in response to changes in sound, social interactions and identity and coping with the daily frustrations required to communicate with others. Abandonment and uncertainty characterised the treatment burden; participants engaged in emotional work to adjust to hearing technology and deal with the uncertainty of how their hearing might progress. To ameliorate the burdens, participants drew on internal resources (psychological, health literacy, cognitive) and external resources (social support, financial, information, technology). CONCLUSIONS: The workload of hearing loss appears largely devolved to the patient and is not always visible. Our work indicates the need to widen approaches in audiological care through the implementation of lifeworld-led care, family-centred care and peer support to build support for those with hearing loss. PATIENT OR PUBLIC CONTRIBUTION: We developed the project in consultation with members of the public who have lived experience of hearing loss recruited through Aston University and volunteer links to audiology services. We also consulted people more likely to be affected by hearing loss adults including adults with learning disabilities, older adults in residential care and people from South Asia (Bangladeshi, Indian and Pakistani communities). These individuals commented on the study aims, interview schedule and participant recruitment practices. One of our co-authors (expert by experience) contributed to the development and interpretation of themes and preparation of the final manuscript.
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Adaptação Psicológica , Efeitos Psicossociais da Doença , Perda Auditiva , Entrevistas como Assunto , Pesquisa Qualitativa , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Masculino , Idoso , Perda Auditiva/psicologia , Perda Auditiva/terapia , Idoso de 80 Anos ou mais , Adolescente , Adulto JovemRESUMO
OBJECTIVE: This study aimed to provide a conceptual model to understand what typifies the lived experience of hearing loss. DESIGN: A grounded theory informed study of adults with hearing loss (n = 46) who participated in individual interviews. The data were analysed in line with the constant comparative approach of grounded theory. A substantial patient and public engagement (PPIE) strategy underpinned decisions and processes throughout. STUDY SAMPLE: Adults were recruited from age bands (16-29; 30-49;50-79 and 80 upwards) to provide different lived experience. We recruited individuals from across the UK including urban, sub-urban and rural communities and included a typical constituency of each location including black and minority ethnic participants. Our PPIE groups included adults often marginalised in research including South Asian community groups, adults in residential care and those with additional disabilities. RESULTS: We identified the consistent features of the lived experience with hearing loss, as the individualised responsibility that hearing loss confers. These are an individual auditory lifeworld; social comparison and social support; individual and patient-centred care and individual agency and capability. CONCLUSIONS: This work provides new insights for those practising audiology and highlights the importance of building social support systems through implementation of family and peer support approaches.
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OBJECTIVE: This project sought to investigate the impact of a multi-national peer learning initiative in facilitating a student-led conference on person-centred care (PCC). The primary objective was to assess students' comprehension of PCC elements before and after engaging in the opportunity, with a concurrent evaluation of the efficacy of the opportunity. DESIGN: A mixed-methods study protocol was followed. Following the conference, participants completed a four-part survey including (a) demographics, (b) retrospective pre-post Likert scale, (c) Likert rating of conference experience and (d) five open-ended questions. STUDY SAMPLE: One hundred and four participants (92.4% female) with a mean age of 21 years (0.07 SD) participated in the study. RESULTS: A significant difference in awareness pre-post conference was demonstrated across all topics (WSR, p < 0.001) with participants satisfied with the conference. Qualitative analysis revealed three main themes: (a) application of PCC; (b) perspectives of PCC; and () barriers to PCC; with nine sub-themes. CONCLUSION: The conference was beneficial in enhancing students' awareness of topics and principles of PCC. Innovative pedagogical approaches should be considered in order to enhance healthcare education allowing future clinicians to better meet the dynamic needs of their clients.
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Modern and effective patient care requires specialist healthcare professionals working together. Interprofessional learning (IPL) seeks to provide opportunities for different healthcare disciplines to learn with, from and about each other. This study focused on the delivery and evaluation of a cytomegalovirus (CMV) case study workshop to facilitate IPL between two Health and Care Professions Council (HCPC) regulated courses: Biomedical Science and Audiology. The 2 h online workshop consisted of 1) defining the roles, responsibilities and skills of the two healthcare professions, 2) the structure of the Biomedical Science and Audiology departments, 3) routes to HCPC registration, 4) core curriculum of both degree programmes and 5) interpreting interdisciplinary data related to a CMV patient case. The workshop was interactive, with the virtual learning environment promoting peer discussions and the use of online polling. Student responses were collected through an online questionnaire. A total of 108 respondents completed a post-event survey and Mann-Whitney U tests revealed there were no significant differences in the responses between the two student cohorts in response to each of the survey statements (p > 0.05). A total of 82.4% of students agreed that they need to know the role of other healthcare professionals for their future practice, whilst 84.2% agreed that the CMV case study was a good format to facilitate effective IPL. A total of 93.5% of respondents recognised the importance of both professions in diagnosing a patient with CMV. Thematic analysis identified four common themes, including appreciation of shared roles, recognition of similarities in registration pathways, working together to provide holistic patient care and the role of clinicians in the patient journey. This novel collaboration between Biomedical Science and Audiology facilitated effective IPL whilst meeting the interprofessional education HCPC requirements. Collaborative working is an essential component of delivering effective patient care and allied healthcare degrees need to provide opportunities within their curriculum to foster this. We hope this study encourages other higher education institutes to expand and develop their current IPL activities to include a broader spectrum of healthcare courses.
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Audiologia , Infecções por Citomegalovirus , Humanos , Citomegalovirus , Relações Interprofissionais , Estudantes , Infecções por Citomegalovirus/diagnósticoRESUMO
INTRODUCTION: Hearing loss is a common chronic health condition and adversely affects communication and social function resulting in loneliness, social isolation and depression. We know little about the patient experience of living with hearing loss and their views on the quality of the audiology service. In this study, we will develop and validate the first patient-reported experience measure (PREM) to understand patients' experiences of living with hearing loss and their healthcare interactions with audiology services. METHODS AND ANALYSIS: We will develop the PREM in three phases: (1) development of PREM prototype (items/statements) derived from previous qualitative work and narrative review, (2) cognitive interview testing of the PREM prototype using a 'think aloud' technique to examine the acceptability and comprehensibility of the tool and refine accordingly and (3) psychometric testing of the modified PREM with 300 participants to assess the reliability and validity of the tool using Rasch analyses with sequential item reduction. Eligible participants will be young people and adults aged 16 years and over who have hearing loss. Participants will be recruited from three clinical sites located in England (Bath, Bristol) and Scotland (Tayside) and non-clinical settings (eg, lip-reading classes, residential care settings, national charity links, social media). ETHICS AND DISSEMINATION: The study was approved by the West of Scotland Research Ethics Service (approval date: 6 May 2022; ref: 22/WS/0057) and the Health Research Authority and Health and Care Research Wales (HCRW) Approval (approval date: 14 June 2022; IRAS project ID: 308816). Findings will be shared with our patient and public involvement groups, academics, audiology communities and services and local commissioners via publications and presentations. The PREM will be made available to clinicians and researchers without charge.
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Surdez , Perda Auditiva , Adulto , Humanos , Adolescente , Reprodutibilidade dos Testes , Perda Auditiva/diagnóstico , Inglaterra , Medidas de Resultados Relatados pelo Paciente , Literatura de Revisão como AssuntoRESUMO
INTRODUCTION: Worldwide, hearing loss is a significant public health issue and one of the most common chronic health conditions experienced by older adults. Hearing loss is associated with communication difficulties, social withdrawal, isolation and lower quality of life. Although hearing aid technology has improved significantly, the workload of managing hearing aids has increased. The aim of this qualitative study is to develop a novel theory of people's lived experience of hearing loss across the lifespan. METHODS: Eligible participants will be young people and adults aged 16 years and above who have a hearing loss and carers/family members of people with a hearing loss. This study will use individual, in-depth face-to-face or online interviews. With participants' permission, interviews will be audio-recorded and transcribed verbatim. A grounded theory approach to concurrent data gathering and analysis will develop grouped codes and categories and link these to provide a novel theory to describe the experience of hearing loss. ETHICS AND DISSEMINATION: The study was approved by the West of Scotland Research Ethics Service (approval date: 6 May 2022 ref: 22/WS/0057) and the Health Research Authority and Health and Care Research Wales Approval (approval date: 14 June 2022; IRAS project ID: 308816). The research will inform the development of a Patient Reported Experience Measure to improve the information and support given to patients. Findings will be disseminated through peer-reviewed articles and at academic conferences, as well as to our patient and public involvement groups, healthcare professionals, audiology services and local commissioners.
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Surdez , Auxiliares de Audição , Perda Auditiva , Humanos , Idoso , Adolescente , Qualidade de Vida , Perda Auditiva/reabilitação , Pesquisa Qualitativa , Escócia , Medidas de Resultados Relatados pelo PacienteRESUMO
SARS-CoV-2 is a lipid-enveloped Betacoronavirus and cause of the Covid-19 pandemic. To study the three-dimensional architecture of the virus, we perform electron cryotomography (cryo-ET) on SARS-Cov-2 virions and three variants revealing particles of regular cylindrical morphology. The ribonucleoprotein particles packaging the genome in the virion interior form a dense, double layer assembly with a cylindrical shape related to the overall particle morphology. This organisation suggests structural interactions important to virus assembly.
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COVID-19 , SARS-CoV-2 , Humanos , Pandemias , Elétrons , Microscopia Crioeletrônica/métodos , VírionRESUMO
Several variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have emerged during the current coronavirus disease 2019 (COVID-19) pandemic. Although antibody cross-reactivity with the spike glycoproteins (S) of diverse coronaviruses, including endemic common cold coronaviruses (HCoVs), has been documented, it remains unclear whether such antibody responses, typically targeting the conserved S2 subunit, contribute to protection when induced by infection or through vaccination. Using a mouse model, we found that prior HCoV-OC43 S-targeted immunity primes neutralizing antibody responses to otherwise subimmunogenic SARS-CoV-2 S exposure and promotes S2-targeting antibody responses. Moreover, vaccination with SARS-CoV-2 S2 elicited antibodies in mice that neutralized diverse animal and human alphacoronaviruses and betacoronaviruses in vitro and provided a degree of protection against SARS-CoV-2 challenge in vivo. Last, in mice with a history of SARS-CoV-2 Wuhan-based S vaccination, further S2 vaccination induced broader neutralizing antibody response than booster Wuhan S vaccination, suggesting that it may prevent repertoire focusing caused by repeated homologous vaccination. These data establish the protective value of an S2-targeting vaccine and support the notion that S2 vaccination may better prepare the immune system to respond to the changing nature of the S1 subunit in SARS-CoV-2 variants of concern, as well as to future coronavirus zoonoses.
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Vacinas contra COVID-19 , COVID-19 , Coronavirus Humano OC43 , Glicoproteína da Espícula de Coronavírus , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Anticorpos Amplamente Neutralizantes , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Coronavirus Humano OC43/imunologia , Humanos , Camundongos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/imunologia , VacinaçãoRESUMO
Recently emerged variants of SARS-CoV-2 contain in their surface spike glycoproteins multiple substitutions associated with increased transmission and resistance to neutralising antibodies. We have examined the structure and receptor binding properties of spike proteins from the B.1.1.7 (Alpha) and B.1.351 (Beta) variants to better understand the evolution of the virus in humans. Spikes of both variants have the same mutation, N501Y, in the receptor-binding domains. This substitution confers tighter ACE2 binding, dependent on the common earlier substitution, D614G. Each variant spike has acquired other key changes in structure that likely impact virus pathogenesis. The spike from the Alpha variant is more stable against disruption upon binding ACE2 receptor than all other spikes studied. This feature is linked to the acquisition of a more basic substitution at the S1-S2 furin site (also observed for the variants of concern Delta, Kappa, and Omicron) which allows for near-complete cleavage. In the Beta variant spike, the presence of a new substitution, K417N (also observed in the Omicron variant), in combination with the D614G, stabilises a more open spike trimer, a conformation required for receptor binding. Our observations suggest ways these viruses have evolved to achieve greater transmissibility in humans.
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Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/metabolismo , Mutação de Sentido Incorreto , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/ultraestrutura , Sítios de Ligação/genética , COVID-19/transmissão , COVID-19/virologia , Microscopia Crioeletrônica , Efeito Citopatogênico Viral/genética , Evolução Molecular , Interações Hospedeiro-Patógeno , Humanos , Cinética , Modelos Moleculares , Ligação Proteica , Domínios Proteicos , SARS-CoV-2/metabolismo , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismoRESUMO
[This corrects the article DOI: 10.1371/journal.ppat.1009352.].
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Neuraminidase (NA) inhibitors (NAI), oseltamivir and zanamivir, are the main antiviral medications for influenza and monitoring of susceptibility to these antivirals is routinely done by determining 50â% inhibitory concentrations (IC50) with MUNANA substrate. During 2010-2019, levels of A(H3N2) viruses presenting reduced NAI inhibition (RI) were low (~0.75â%) but varied year-on-year. The highest proportions of viruses showing RI were observed during the 2013-2014, 2016-2017 and 2017-2018 Northern Hemisphere seasons. The majority of RI viruses were found to contain positively charged NA amino acid substitutions of N329K, K/S329R, S331R or S334R, being notably higher during the 2016-2017 season. Sialidase activity kinetics were determined for viruses of RI phenotype and contemporary wild-type (WT) viruses showing close genetic relatedness and displaying normal inhibition (NI). RI phenotypes resulted from reduced sialidase activity compared to relevant WT viruses. Those containing S329R or N329K or S331R showed markedly higher Km for the substrate and Ki values for NAIs, while those with S334R showed smaller effects. Substitutions at N329 and S331 disrupt a glycosylation sequon (NDS), confirmed to be utilised by mass spectrometry. However, gain of positive charge at all three positions was the major factor influencing the kinetic effects, not loss of glycosylation. Because of the altered enzyme characteristics NAs carrying these substitutions cannot be assessed reliably for susceptibility to NAIs using standard MUNANA-based assays due to reductions in the affinity of the enzyme for its substrate and the concentration of the substrate usually used.
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Vírus da Influenza A Subtipo H3N2/enzimologia , Neuraminidase/metabolismo , Substituição de Aminoácidos , Antivirais/farmacologia , Inibidores Enzimáticos/farmacologia , Genes Virais , Glicosilação , Sequenciamento de Nucleotídeos em Larga Escala , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/genética , Cinética , Modelos Moleculares , Neuraminidase/antagonistas & inibidores , Neuraminidase/química , Neuraminidase/genética , Oseltamivir/farmacologia , Conformação Proteica , Zanamivir/farmacologiaAssuntos
Vacinas contra COVID-19 , COVID-19 , Anticorpos Neutralizantes , Anticorpos Antivirais , Humanos , Diálise Renal , SARS-CoV-2 , Reino Unido , VacinaçãoRESUMO
BACKGROUND: Differences in humoral immunity to coronaviruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), between children and adults remain unexplained, and the effect of underlying immune dysfunction or suppression is unknown. Here, we sought to examine the antibody immune competence of children and adolescents with prevalent inflammatory rheumatic diseases, juvenile idiopathic arthritis (JIA), juvenile dermatomyositis (JDM), and juvenile systemic lupus erythematosus (JSLE) against the seasonal human coronavirus (HCoV)-OC43 that frequently infects this age group. METHODS: Sera were collected from JIA (n = 118), JDM (n = 49), and JSLE (n = 30) patients and from healthy control (n = 54) children and adolescents prior to the coronavirus disease 19 (COVID-19) pandemic. We used sensitive flow-cytometry-based assays to determine titers of antibodies that reacted with the spike and nucleoprotein of HCoV-OC43 and cross-reacted with the spike and nucleoprotein of SARS-CoV-2, and we compared them with respective titers in sera from patients with multisystem inflammatory syndrome in children and adolescents (MIS-C). FINDINGS: Despite immune dysfunction and immunosuppressive treatment, JIA, JDM, and JSLE patients maintained comparable or stronger humoral responses than healthier peers, which was dominated by immunoglobulin G (IgG) antibodies to HCoV-OC43 spike, and harbored IgG antibodies that cross-reacted with SARS-CoV-2 spike. In contrast, responses to HCoV-OC43 and SARS-CoV-2 nucleoproteins exhibited delayed age-dependent class-switching and were not elevated in JIA, JDM, and JSLE patients, which argues against increased exposure. CONCLUSIONS: Consequently, autoimmune rheumatic diseases and their treatment were associated with a favorable ratio of spike to nucleoprotein antibodies. FUNDING: This work was supported by a Centre of Excellence Centre for Adolescent Rheumatology Versus Arthritis grant, 21593, UKRI funding reference MR/R013926/1, the Great Ormond Street Children's Charity, Cure JM Foundation, Myositis UK, Lupus UK, and the NIHR Biomedical Research Centres at GOSH and UCLH. This work was supported by the Francis Crick Institute, which receives its core funding from Cancer Research UK, the UK Medical Research Council, and the Wellcome Trust.
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Doenças Autoimunes , COVID-19 , Coronavirus Humano OC43 , Doenças Reumáticas , Adolescente , Adulto , Anticorpos Antivirais , Formação de Anticorpos , COVID-19/complicações , Criança , Humanos , Imunoglobulina G , Nucleoproteínas , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Síndrome de Resposta Inflamatória SistêmicaRESUMO
Background: The degree of heterotypic immunity induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains is a major determinant of the spread of emerging variants and the success of vaccination campaigns, but remains incompletely understood. Methods: We examined the immunogenicity of SARS-CoV-2 variant B.1.1.7 (Alpha) that arose in the United Kingdom and spread globally. We determined titres of spike glycoprotein-binding antibodies and authentic virus neutralising antibodies induced by B.1.1.7 infection to infer homotypic and heterotypic immunity. Results: Antibodies elicited by B.1.1.7 infection exhibited significantly reduced recognition and neutralisation of parental strains or of the South Africa variant B.1.351 (Beta) than of the infecting variant. The drop in cross-reactivity was significantly more pronounced following B.1.1.7 than parental strain infection. Conclusions: The results indicate that heterotypic immunity induced by SARS-CoV-2 variants is asymmetric. Funding: This work was supported by the Francis Crick Institute and the Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg.
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Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/virologia , SARS-CoV-2/imunologia , Anticorpos Neutralizantes/imunologia , COVID-19/epidemiologia , Reações Cruzadas , Humanos , Pais , África do Sul/epidemiologia , Glicoproteína da Espícula de Coronavírus , Reino Unido/epidemiologiaRESUMO
The coronavirus disease 2019 (COVID-19) pandemic, which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a global public health challenge. While the efficacy of vaccines against emerging and future virus variants remains unclear, there is a need for therapeutics. Repurposing existing drugs represents a promising and potentially rapid opportunity to find novel antivirals against SARS-CoV-2. The virus encodes at least nine enzymatic activities that are potential drug targets. Here, we have expressed, purified and developed enzymatic assays for SARS-CoV-2 nsp13 helicase, a viral replication protein that is essential for the coronavirus life cycle. We screened a custom chemical library of over 5000 previously characterized pharmaceuticals for nsp13 inhibitors using a fluorescence resonance energy transfer-based high-throughput screening approach. From this, we have identified FPA-124 and several suramin-related compounds as novel inhibitors of nsp13 helicase activity in vitro. We describe the efficacy of these drugs using assays we developed to monitor SARS-CoV-2 growth in Vero E6 cells.
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Antivirais/química , Antivirais/farmacologia , Avaliação Pré-Clínica de Medicamentos , RNA Helicases/antagonistas & inibidores , SARS-CoV-2/enzimologia , Bibliotecas de Moléculas Pequenas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Chlorocebus aethiops , Ensaios Enzimáticos , Transferência Ressonante de Energia de Fluorescência , Ensaios de Triagem em Larga Escala , RNA Helicases/metabolismo , Reprodutibilidade dos Testes , SARS-CoV-2/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Suramina/farmacologia , Células Vero , Proteínas não Estruturais Virais/metabolismoRESUMO
Valorization of vegetable oil waste residues is gaining importance due to their high protein and polyphenol contents. Protease inhibitors (PIs), proteins from these abundantly available waste residues, have recently gained importance in treating chronic diseases. This research aimed to use canola meal of genetically diverse Brassica napus genotypes, BLN-3347 and Rivette, to identify PIs with diverse functionalities in therapeutic and pharmacological applications. The canola meal PI purification steps involved: native PAGE and trypsin inhibition activity, followed by ammonium sulfate fractionation, anion exchange, gel filtration, and reverse-phase chromatography. The purified PI preparations were characterized using SDS-PAGE, isoelectric focusing (IEF), and N terminal sequencing. SDS-PAGE analysis of PI preparations under native reducing and nonreducing conditions revealed three polymorphic PIs in each genotype. The corresponding IEF of the genotype BLN-3347, exhibited three acidic isoforms with isoelectric points (pI) of 4.6, 4.0, and 3.9, while Rivette possessed three isoforms, exhibiting two basic forms of pI 8.65 and 9.9, and one acidic of pI 6.55. Purified PI preparations from both the genotypes displayed dipeptidyl peptidase-IV (DPP-IV) and angiotensin-converting enzyme (ACE) inhibition activities; the BLN-3347 PI preparation exhibited a strong inhibitory effect with lower IC50 values (DPP-IV 37.42 µg/mL; ACE 129 µg/mL) than that from Rivette (DPP-IV 67.97 µg/mL; ACE 376.2 µg/mL). In addition to potential human therapy, these highly polymorphic PIs, which can inhibit damaging serine proteases secreted by canola plant pathogens, have the potential to be used by canola plant breeders to seek qualitative trait locus (QTLs) linked to genes conferring resistance to canola diseases.
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Anti-Hipertensivos/farmacologia , Brassica napus/química , Dipeptidil Peptidase 4/química , Inibidores Enzimáticos/farmacologia , Hipoglicemiantes/farmacologia , Peptidil Dipeptidase A/química , Sequência de Aminoácidos , Anti-Hipertensivos/química , Anti-Hipertensivos/isolamento & purificação , Brassica napus/genética , Brassica napus/metabolismo , Dipeptidil Peptidase 4/metabolismo , Ensaios Enzimáticos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Genótipo , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Focalização Isoelétrica , Cinética , Extração Líquido-Líquido/métodos , Peptidil Dipeptidase A/metabolismo , Extratos Vegetais/químicaRESUMO
Influenza A viruses encode several accessory proteins that have host- and strain-specific effects on virulence and replication. The accessory protein PA-X is expressed due to a ribosomal frameshift during translation of the PA gene. Depending on the particular combination of virus strain and host species, PA-X has been described as either acting to reduce or increase virulence and/or virus replication. In this study, we set out to investigate the role PA-X plays in H9N2 avian influenza viruses, focusing on the natural avian host, chickens. We found that the G1 lineage A/chicken/Pakistan/UDL-01/2008 (H9N2) PA-X induced robust host shutoff in both mammalian and avian cells and increased virus replication in mammalian, but not avian cells. We further showed that PA-X affected embryonic lethality in ovo and led to more rapid viral shedding and widespread organ dissemination in vivo in chickens. Overall, we conclude PA-X may act as a virulence factor for H9N2 viruses in chickens, allowing faster replication and wider organ tropism.
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Vírus da Influenza A Subtipo H9N2/metabolismo , Influenza Aviária/virologia , Influenza Humana/virologia , Proteínas Repressoras/metabolismo , Proteínas não Estruturais Virais/metabolismo , Fatores de Virulência/metabolismo , Animais , Linhagem Celular , Galinhas , Citocinas/genética , Citocinas/imunologia , Humanos , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/patogenicidade , Influenza Aviária/genética , Influenza Aviária/imunologia , Influenza Humana/genética , Influenza Humana/imunologia , Pulmão/imunologia , Pulmão/virologia , Camundongos , Proteínas Repressoras/genética , Proteínas não Estruturais Virais/genética , Fatores de Virulência/genética , Replicação Viral , Eliminação de Partículas ViraisRESUMO
Serological and plasmablast responses and plasmablast-derived IgG monoclonal antibodies (MAbs) have been analysed in three COVID-19 patients with different clinical severities. Potent humoral responses were detected within 3 weeks of onset of illness in all patients and the serological titre was elicited soon after or concomitantly with peripheral plasmablast response. An average of 13.7% and 3.5% of plasmablast-derived MAbs were reactive with virus spike glycoprotein or nucleocapsid, respectively. A subset of anti-spike (10 of 32) antibodies cross-reacted with other betacoronaviruses tested and harboured extensive somatic mutations, indicative of an expansion of memory B cells upon SARS-CoV-2 infection. Fourteen of 32 anti-spike MAbs, including five anti-receptor-binding domain (RBD), three anti-non-RBD S1 and six anti-S2, neutralised wild-type SARS-CoV-2 in independent assays. Anti-RBD MAbs were further grouped into four cross-inhibiting clusters, of which six antibodies from three separate clusters blocked the binding of RBD to ACE2 and five were neutralising. All ACE2-blocking anti-RBD antibodies were isolated from two recovered patients with prolonged fever, which is compatible with substantial ACE2-blocking response in their sera. Finally, the identification of non-competing pairs of neutralising antibodies would offer potential templates for the development of prophylactic and therapeutic agents against SARS-CoV-2.