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1.
Emerg Infect Dis ; 29(1): 184-188, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36454718

RESUMO

Since June 2020, the SARS-CoV-2 Immunity and Reinfection Evaluation (SIREN) study has conducted routine PCR testing in UK healthcare workers and sequenced PCR-positive samples. SIREN detected increases in infections and reinfections and delected Omicron subvariant waves emergence contemporaneous with national surveillance. SIREN's sentinel surveillance methods can be used for variant surveillance.


Assuntos
COVID-19 , Humanos , Animais , COVID-19/diagnóstico , COVID-19/epidemiologia , SARS-CoV-2/genética , Reino Unido/epidemiologia , Pessoal de Saúde , Reinfecção , Urodelos
2.
J Virol ; 94(24)2020 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-32967963

RESUMO

Human papillomavirus (HPV) is the causative agent of cervical and other epithelial cancers. Naturally occurring variants of HPV have been classified into lineages and sublineages based on their whole-genome sequences, but little is known about the impact of this diversity on the structure and function of viral gene products. The HPV capsid is an icosahedral lattice comprising 72 pentamers of the major capsid protein (L1) and the associated minor capsid protein (L2). We investigated the potential impact of this genome variation on the capsid antigenicity of lineage and sublineage variants of seven vaccine-relevant, oncogenic HPV genotypes by using a large panel of monoclonal antibodies (MAbs) raised against the L1 proteins of lineage A antigens. Each genotype had at least one variant that displayed a ≥4-fold reduced neutralizing antibody sensitivity against at least one MAb, demonstrating that naturally occurring variation can affect one or more functional antigenic determinants on the HPV capsid. For HPV16, HPV18, HPV31, and HPV45, the overall impact was of a low magnitude. For HPV33 (sublineages A2 and A3 and lineages B and C), HPV52 (lineage D), and HPV58 (lineage C), however, variant residues in the indicated lineages and sublineages reduced their sensitivity to neutralization by all MAbs by up to 1,000-fold, suggesting the presence of key antigenic determinants on the surface of these capsids. These determinants were resolved further by site-directed mutagenesis. These data improve our understanding of the impact of naturally occurring variation on the antigenicity of the HPV capsid of vaccine-relevant oncogenic HPV genotypes.IMPORTANCE Human papillomavirus (HPV) is the causative agent of cervical and some other epithelial cancers. HPV vaccines generate functional (neutralizing) antibodies that target the virus particles (or capsids) of the most common HPV cancer-causing genotypes. Each genotype comprises variant forms that have arisen over millennia and which include changes within the capsid proteins. In this study, we explored the potential for these naturally occurring variant capsids to impact recognition by neutralizing monoclonal antibodies. All genotypes included at least one variant form that exhibited reduced recognition by at least one antibody, with some genotypes affected more than others. These data highlight the impact of naturally occurring variation on the structure of the HPV capsid proteins of vaccine-relevant oncogenic HPV genotypes.


Assuntos
Alphapapillomavirus/imunologia , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Proteínas do Capsídeo/imunologia , Genótipo , Vacinas contra Papillomavirus/imunologia , Alphapapillomavirus/genética , Anticorpos Monoclonais/genética , Antígenos Virais/genética , Proteínas do Capsídeo/genética , Epitopos , Genes Virais/genética , Variação Genética , Papillomavirus Humano 16/genética , Papillomavirus Humano 31/genética , Humanos , Testes de Neutralização , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/imunologia , Oncogenes , Papillomaviridae , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/genética
3.
Biochem Pharmacol ; 172: 113774, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31870769

RESUMO

Acetaminophen is both widely used to treat children with fever and is also responsible for thousands being hospitalised annually. Historically the antipyretic actions of acetaminophen were attributed to the inhibition of cyclooxygenase (COX-1/2) enzymes and more recently a novel COX-1 variant (COX-3) located in the brain. However, the evidence for acetaminophen-mediated COX inhibition remains contentious. This study assesses the impact of acetaminophen and other putative COX-3 inhibitors on the release of fatty acids during lipolysis as an alternative mechanism by which antipyretics can reduce body temperature during fever. 3T3-L1 adipocytes, primary brown adipocytes and isolated mitochondria were exposed to COX-3 inhibitors and lipolysis and mitochondrial electron transport chain function assessed. Acetaminophen, aminopyrine and antipyrine at 1-10 mM caused a significant decrease (up to 70%; P < 0.01, from control) in lipolysis within 1, 3 and 24 h without affecting cell viability. The inhibition was observed regardless of where along its signalling pathway lipolysis was stimulated. All three compounds were found to significantly attenuate mitochondrial function by up to 30% for complex I and 40% for complex II (P < 0.01, from control). These novel observations combined with the known limited inhibition of the COX enzymes by acetaminophen suggest both the antipyretic and hypothermia induced by acetaminophen and related compounds could be attributed to the direct inhibition of lipolysis and mitochondrial function, rather than cyclooxygenase inhibition centrally. Further these observations could provide new drug targets for reducing fever with the added bonus of fewer individuals being hospitalized by accidental acetaminophen overdose.


Assuntos
Acetaminofen/farmacologia , Adipócitos/efeitos dos fármacos , Antipiréticos/farmacologia , Temperatura Corporal/efeitos dos fármacos , Temperatura Corporal/fisiologia , Lipólise/efeitos dos fármacos , Células 3T3-L1 , 8-Bromo Monofosfato de Adenosina Cíclica/metabolismo , Adipócitos/fisiologia , Agonistas Adrenérgicos beta/farmacologia , Aminopirina/farmacologia , Animais , Antipirina/farmacologia , Diferenciação Celular , Colforsina/metabolismo , Isoproterenol/farmacologia , Camundongos , Ratos , Ratos Wistar
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