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1.
J Med Virol ; 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: covidwho-2235950

RESUMO

Recognizing aberrant cytoplasmic dsDNA and stimulating cGAS-STING-mediated innate immunity is essential for the host defense against viruses. Recent studies have reported that SARS-CoV-2 infection, responsible for the COVID-19 pandemic, triggers cGAS-STING activation. cGAS-STING activation can trigger IRF3-Type I interferon (IFN) and autophagy-mediated antiviral activity. Although viral evasion of STING-triggered IFN-mediated antiviral function has been well studied, studies concerning viral evasion of STING-triggered autophagy-mediated antiviral function are scarce. In the present study, we have discovered that SARS-CoV-2 ORF3a is a unique viral protein that can interact with STING and disrupt the STING-LC3 interaction, thus blocking cGAS-STING-induced autophagy but not IRF3-Type I IFN induction. This novel function of ORF3a, distinct from targeting autophagosome-lysosome fusion, is a selective inhibition of STING-triggered autophagy to facilitate viral replication. We have also found that activation of bat STING can induce autophagy and antiviral activity despite its defect in IFN induction. Furthermore, ORF3a from bat coronaviruses can block bat STING-triggered autophagy and antiviral function. Interestingly, the ability to inhibit STING-induced autophagy appears to be an acquired function of SARS-CoV-2 ORF3a, since SARS-CoV ORF3a lacks this function. Taken together, these discoveries identify ORF3a as a potential target for intervention against COVID-19.

2.
J Med Virol ; 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: covidwho-2235534

RESUMO

Recognizing aberrant cytoplasmic double-stranded DNA and stimulating innate immunity is essential for the host's defense against viruses and tumors. Cyclic GMP-AMP (cGAMP) synthase (cGAS) is a cytosolic DNA sensor that synthesizes the second messenger 2'3'-cGAMP and subsequently activates stimulator of interferon genes (STING)-mediated activation of TANK-binding kinase 1 (TBK1)/interferon regulatory factor 3 (IRF3) and the production of type I interferon (IFN-I). Both the cGAS-STING-mediated IFN-I antiviral defense and the countermeasures developed by diverse viruses have been extensively studied. However, recent studies have revealed a convergent evolutionary feature of severe acute respiratory syndrome coronavirus 2 and human immunodeficiency virus (HIV) viral proteins in terms of the selective regulation of cGAS-STING-mediated nuclear factor-κB (NF-κB) signaling without any effect on cGAS-STING-mediated TBK1/IRF3 activation and IFN production. The potential beneficial effect of this cGAS-STING-mediated, NF-κB-dependent antiviral effect, and the possible detrimental effect of IFN-I in the pathogenesis of coronavirus disease 2019 and HIV infection deserve more attention and future investigation.

3.
BMJ Open ; 12(9): e060290, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: covidwho-2213946

RESUMO

INTRODUCTION: Acute variceal haemorrhage (AVH) in patients with cirrhosis remains a topic of great interest. Although several guidelines recommend endoscopy within 24 hours after AVH, there is no consensus on the most appropriate time to perform this intervention. The purpose of this study is to identify whether urgent endoscopy (within 6 hours after gastroenterological consultation) is superior to non-urgent endoscopy (between 6 hours and 24 hours after gastroenterological consultation) in reducing the rebleeding rate of these patients. METHODS AND ANALYSIS: This is a single-centred, prospective, randomised clinical trial. Between March 2021 and December 2023, an estimated 400 patients will be randomised in a 1:1 ratio to receive endoscopic intervention either within 6 hours or between 6 and 24 hours after gastroenterological consultation. Randomisation will be conducted by permuted block randomisation, with stratification by age, systolic blood pressure and pulse rate. The primary efficacy endpoint is rebleeding within 42 days after control of AVH. The secondary efficacy endpoints mainly include all-cause mortality within 42 days after randomisation, persistent bleeding, length of hospitalisation, etc. ETHICS AND DISSEMINATION: The study protocol was approved by the Ethical Committees of Jinling Hospital (authorised ethics no. DZQH-KYLL-21-01). This trial will provide valuable insights into the timing of endoscopic intervention for AVH in patients with cirrhosis. Furthermore, the trial results and conclusions could provide high-quality evidence to guide clinical research and treatment. TRIAL REGISTRATION NUMBER: NCT04786743.


Assuntos
COVID-19 , Humanos , COVID-19/complicações , SARS-CoV-2 , Cirrose Hepática/complicações , Hemorragia/complicações , Endoscopia , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
4.
Fluctuation & Noise Letters ; : 1, 2022.
Artigo em Inglês | Academic Search Complete | ID: covidwho-2113192

RESUMO

The volatility and cross-correlations of the energy market and the stock market during the COVID-19 pandemic have been paid close attention by scholars and investors. In this paper, we use the asymmetric multifractal analysis methods to study the fluctuation characteristics, market risks and cross-correlations of the Chinese energy futures market (EFM) and two energy stock markets before and after the COVID-19 outbreak, while the return series of Shanghai fuel oil futures, CSI Energy Index and CSI Mainland New Energy Theme Index are considered. The empirical evidences indicate that the auto- and cross-correlations of the three markets have the asymmetric multifractality, and that the multifractality of the cross-correlations is mainly caused by the fat-tailed distribution of the original series. After the COVID-19 outbreak, the risks of both the traditional energy stock market in the uptrend and the entire new energy stock market become larger, while those of the entire EFM become smaller. In addition, the COVID-19 pandemic has increased the multifractality of the cross-correlations between the energy futures and energy stock markets when the EFM is in downward trend. [ FROM AUTHOR]

5.
Pers Individ Dif ; 192: 111589, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: covidwho-1839183

RESUMO

To be or not to be quarantined? That is the question posed by COVID-19 pandemic to almost every resident in the world. Approximately three months after the first application of the COVID-19 lockdown to residents in 17 Asian, African, European, American, and Oceanian countries, we carried out a cross-national survey of 26,266 residents via online platforms such as Sojump and Prolific to investigate their willingness to quarantine and its influencing factors. Findings show that 1) The willingness to quarantine is low in countries with high long-term orientation; 2) Females are more willing to be quarantined than males; 3) Gender difference on willingness to quarantine is large among people with older age and low education. Theoretical and managerial implications are discussed. Understanding how culture and demographics affect people's willingness to quarantine not only provides insight into how to respond to the current pandemic, but also helps the world prepare for future crises.

6.
Signal Transduct Target Ther ; 6(1): 123, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: covidwho-1135650

RESUMO

The emergence of SARS-CoV-2 has resulted in the COVID-19 pandemic, leading to millions of infections and hundreds of thousands of human deaths. The efficient replication and population spread of SARS-CoV-2 indicates an effective evasion of human innate immune responses, although the viral proteins responsible for this immune evasion are not clear. In this study, we identified SARS-CoV-2 structural proteins, accessory proteins, and the main viral protease as potent inhibitors of host innate immune responses of distinct pathways. In particular, the main viral protease was a potent inhibitor of both the RLR and cGAS-STING pathways. Viral accessory protein ORF3a had the unique ability to inhibit STING, but not the RLR response. On the other hand, structural protein N was a unique RLR inhibitor. ORF3a bound STING in a unique fashion and blocked the nuclear accumulation of p65 to inhibit nuclear factor-κB signaling. 3CL of SARS-CoV-2 inhibited K63-ubiquitin modification of STING to disrupt the assembly of the STING functional complex and downstream signaling. Diverse vertebrate STINGs, including those from humans, mice, and chickens, could be inhibited by ORF3a and 3CL of SARS-CoV-2. The existence of more effective innate immune suppressors in pathogenic coronaviruses may allow them to replicate more efficiently in vivo. Since evasion of host innate immune responses is essential for the survival of all viruses, our study provides insights into the design of therapeutic agents against SARS-CoV-2.


Assuntos
Imunidade Inata , Proteínas de Membrana/imunologia , Nucleotidiltransferases/imunologia , RNA Viral/imunologia , SARS-CoV-2/imunologia , Transdução de Sinais/imunologia , Proteínas Virais/imunologia , Células A549 , Animais , Galinhas , Células HEK293 , Células HeLa , Humanos , Ligases/imunologia , Camundongos
7.
JCO Glob Oncol ; 6: 1494-1509, 2020 10.
Artigo em Inglês | MEDLINE | ID: covidwho-814636

RESUMO

PURPOSE: The coronavirus disease 2019 (COVID-19) pandemic has had a global impact, and Singapore has seen 33,000 confirmed cases. Patients with cancer, their caregivers, and health care workers (HCWs) need to balance the challenges associated with COVID-19 while ensuring that cancer care is not compromised. This study aimed to evaluate the psychological effect of COVID-19 on these groups and the prevalence of burnout among HCWs. METHODS: A cross-sectional survey of patients, caregivers, and HCWs at the National Cancer Centre Singapore was performed over 17 days during the lockdown. The Generalized Anxiety Disorder-7 and Maslach Burnout Inventory were used to assess for anxiety and burnout, respectively. Self-reported fears related to COVID-19 were collected. RESULTS: A total of 624 patients, 408 caregivers, and 421 HCWs participated in the study, with a response rate of 84%, 88%, and 92% respectively. Sixty-six percent of patients, 72.8% of caregivers, and 41.6% of HCWs reported a high level of fear from COVID-19. The top concern of patients was the wide community spread of COVID-19. Caregivers were primarily worried about patients dying alone. HCWs were most worried about the relatively mild symptoms of COVID-19. The prevalence of anxiety was 19.1%, 22.5%, and 14.0% for patients, caregivers, and HCWs, respectively. Patients who were nongraduates and married, and caregivers who were married were more anxious. The prevalence of burnout in HCWs was 43.5%, with more anxious and fearful HCWs reporting higher burnout rates. CONCLUSION: Fears and anxiety related to COVID-19 are high. Burnout among HCWs is similar to rates reported prepandemic. An individualized approach to target the specific fears of each group will be crucial to maintain the well-being of these vulnerable groups and prevent burnout of HCWs.


Assuntos
Ansiedade/epidemiologia , Esgotamento Profissional/epidemiologia , Cuidadores/psicologia , Infecções por Coronavirus/psicologia , Neoplasias/psicologia , Pneumonia Viral/psicologia , Adulto , Idoso , Ansiedade/diagnóstico , Ansiedade/psicologia , Betacoronavirus/patogenicidade , Esgotamento Profissional/diagnóstico , Esgotamento Profissional/psicologia , COVID-19 , Institutos de Câncer/organização & administração , Institutos de Câncer/normas , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Estudos Transversais , Medo/psicologia , Feminino , Pessoal de Saúde/psicologia , Acessibilidade aos Serviços de Saúde/organização & administração , Acessibilidade aos Serviços de Saúde/normas , Humanos , Controle de Infecções/normas , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Transmissão de Doença Infecciosa do Profissional para o Paciente/prevenção & controle , Masculino , Oncologia/organização & administração , Oncologia/normas , Pessoa de Meia-Idade , Neoplasias/terapia , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Prevalência , SARS-CoV-2 , Singapura/epidemiologia , Carga de Trabalho/psicologia
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