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1.
Economics, Law, and Institutions in Asia Pacific ; : 127-143, 2022.
Artigo em Inglês | Scopus | ID: covidwho-1575562

RESUMO

The Nagahama Prospective Cohort for Comprehensive Human Bioscience is the first large-scale multipurpose genome cohort in Japan. The project started in 2007 with a new concept of “pre-primary prevention” aiming to realize personalized early disease prevention based on the genetic background of each individual, detailed measurement of biomolecules in the body and health-related clinical information over time together with the environment and lifestyle. The uniqueness of this human biology study is the multidisciplinary research infrastructure incorporating information science, mathematics, and social sciences. Cutting-edge technology in genomic medicine such as next-generation sequencing and multi-omics measurements is combined with an objective evaluation of environmental factors, records on sleep and other body activities, and the comprehensive social capital survey. Various research programmes have been launched on this information infrastructure, such as a skin aging study with industry and an association study between genetic factors and social and economic behaviour in collaboration with a governmental research institute. From 2020, a new socio-life science study for the COVID-19 pandemic consisting of SARS-CoV-2 antibody measurement and social capital surveys was initiated as a joint research effort of academia, government and industry. © 2022, RIETI.

2.
Elife ; 92020 06 15.
Artigo em Inglês | MEDLINE | ID: covidwho-1497818

RESUMO

The COVID-19 pandemic has resulted in school closures and distancing requirements that have disrupted both work and family life for many. Concerns exist that these disruptions caused by the pandemic may not have influenced men and women researchers equally. Many medical journals have published papers on the pandemic, which were generated by researchers facing the challenges of these disruptions. Here we report the results of an analysis that compared the gender distribution of authors on 1893 medical papers related to the pandemic with that on papers published in the same journals in 2019, for papers with first authors and last authors from the United States. Using mixed-effects regression models, we estimated that the proportion of COVID-19 papers with a woman first author was 19% lower than that for papers published in the same journals in 2019, while our comparisons for last authors and overall proportion of women authors per paper were inconclusive. A closer examination suggested that women's representation as first authors of COVID-19 research was particularly low for papers published in March and April 2020. Our findings are consistent with the idea that the research productivity of women, especially early-career women, has been affected more than the research productivity of men.


Assuntos
Autoria , Bibliometria , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Pesquisadores/estatística & dados numéricos , Mulheres , COVID-19 , Eficiência , Feminino , Humanos , Medicina , Publicações Periódicas como Assunto/estatística & dados numéricos , Médicas/estatística & dados numéricos , Fatores Sexuais , Isolamento Social , Estados Unidos
3.
Elife ; 92020 04 27.
Artigo em Inglês | MEDLINE | ID: covidwho-1344522

RESUMO

COVID-19 patients can present with pulmonary edema early in disease. We propose that this is due to a local vascular problem because of activation of bradykinin 1 receptor (B1R) and B2R on endothelial cells in the lungs. SARS-CoV-2 enters the cell via ACE2 that next to its role in RAAS is needed to inactivate des-Arg9 bradykinin, the potent ligand of the B1R. Without ACE2 acting as a guardian to inactivate the ligands of B1R, the lung environment is prone for local vascular leakage leading to angioedema. Here, we hypothesize that a kinin-dependent local lung angioedema via B1R and eventually B2R is an important feature of COVID-19. We propose that blocking the B2R and inhibiting plasma kallikrein activity might have an ameliorating effect on early disease caused by COVID-19 and might prevent acute respiratory distress syndrome (ARDS). In addition, this pathway might indirectly be responsive to anti-inflammatory agents.


The COVID-19 pandemic represents an unprecedented threat to global health. Millions of cases have been confirmed around the world, and hundreds of thousands of people have lost their lives. Common symptoms include a fever and persistent cough and COVID-19 patients also often experience an excess of fluid in the lungs, which makes it difficult to breathe. In some cases, this develops into a life-threatening condition whereby the lungs cannot provide the body's vital organs with enough oxygen. The SARS-CoV-2 virus, which causes COVID-19, enters the lining of the lungs via an enzyme called the ACE2 receptor, which is present on the outer surface of the lungs' cells. The related coronavirus that was responsible for the SARS outbreak in the early 2000s also needs the ACE2 receptor to enter the cells of the lungs. In SARS, the levels of ACE2 in the lung decline during the infection. Studies with mice have previously revealed that a shortage of ACE2 leads to increased levels of a hormone called angiotensin II, which regulates blood pressure. As a result, much attention has turned to the potential link between this hormone system in relation to COVID-19. However, other mouse studies have shown that ACE2 protects against a build-up of fluid in the lungs caused by a different molecule made by the body. This molecule, which is actually a small fragment of a protein, lowers blood pressure and causes fluid to leak out of blood vessels. It belongs to a family of molecules known as kinins, and ACE2 is known to inactivate certain kinins. This led van de Veerdonk et al. to propose that the excess of fluid in the lungs seen in COVID-19 patients may be because kinins are not being neutralized due to the shortage of the ACE2 receptor. This had not been hypothesized before, even though the mechanism could be the same in SARS which has been researched for the past 17 years. If this hypothesis is correct, it would mean that directly inhibiting the receptor for the kinins (or the proteins that they come from) may be the only way to stop fluid leaking into the lungs of COVID-19 patients in the early stage of disease. This hypothesis is unproven, and more work is needed to see if it is clinically relevant. If that work provides a proof of concept, it means that existing treatments and registered drugs could potentially help patients with COVID-19, by preventing the need for mechanical ventilation and saving many lives.


Assuntos
Antivirais/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/patologia , Desenvolvimento de Medicamentos , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/patologia , Angioedema/tratamento farmacológico , Angioedema/metabolismo , Angioedema/patologia , Anti-Inflamatórios/uso terapêutico , Betacoronavirus/fisiologia , Antagonistas dos Receptores da Bradicinina/uso terapêutico , COVID-19 , Infecções por Coronavirus/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Humanos , Inflamação/imunologia , Inflamação/patologia , Calicreínas/metabolismo , Cininas/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Pandemias , Pneumonia Viral/metabolismo , Receptor B1 da Bradicinina/metabolismo , Receptor B2 da Bradicinina/metabolismo , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/patologia , Síndrome do Desconforto Respiratório/prevenção & controle , SARS-CoV-2 , Transdução de Sinais
4.
Biochem Mol Biol Educ ; 48(5): 490-491, 2020 09.
Artigo em Inglês | MEDLINE | ID: covidwho-653188

RESUMO

Following the COVID-19 lockdown, the BSc in Human Biology Program of the University of Nicosia switched from face-to-face to online delivery mode. Herein we describe how we identified and managed the challenges that arose to successfully complete the Semester.


Assuntos
Biologia/educação , COVID-19/epidemiologia , Currículo , Educação a Distância , Pandemias , SARS-CoV-2 , Humanos
5.
Elife ; 92020 07 14.
Artigo em Inglês | MEDLINE | ID: covidwho-646829

RESUMO

The pandemic of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has affected more than 10 million people, including pregnant women. To date, no consistent evidence for the vertical transmission of SARS-CoV-2 exists. The novel coronavirus canonically utilizes the angiotensin-converting enzyme 2 (ACE2) receptor and the serine protease TMPRSS2 for cell entry. Herein, building upon our previous single-cell study (Pique-Regi et al., 2019), another study, and new single-cell/nuclei RNA-sequencing data, we investigated the expression of ACE2 and TMPRSS2 throughout pregnancy in the placenta as well as in third-trimester chorioamniotic membranes. We report that co-transcription of ACE2 and TMPRSS2 is negligible in the placenta, thus not a likely path of vertical transmission for SARS-CoV-2. By contrast, receptors for Zika virus and cytomegalovirus, which cause congenital infections, are highly expressed by placental cell types. These data show that the placenta minimally expresses the canonical cell-entry mediators for SARS-CoV-2.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/virologia , Placenta/metabolismo , Placenta/virologia , Pneumonia Viral/transmissão , Receptores Virais/metabolismo , Serina Endopeptidases/metabolismo , Internalização do Vírus , Enzima de Conversão de Angiotensina 2 , Betacoronavirus/metabolismo , COVID-19 , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/transmissão , Feminino , Humanos , Pandemias , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/metabolismo , Pneumonia Viral/virologia , Gravidez , Receptores Virais/genética , SARS-CoV-2 , Serina Endopeptidases/genética , Zika virus , Infecção por Zika virus
6.
Elife ; 92020 07 08.
Artigo em Inglês | MEDLINE | ID: covidwho-636307

RESUMO

Hydroxychloroquine and chloroquine are used extensively in malaria and rheumatological conditions, and now in COVID-19 prevention and treatment. Although generally safe they are potentially lethal in overdose. In-vitro data suggest that high concentrations and thus high doses are needed for COVID-19 infections, but as yet there is no convincing evidence of clinical efficacy. Bayesian regression models were fitted to survival outcomes and electrocardiograph QRS durations from 302 prospectively studied French patients who had taken intentional chloroquine overdoses, of whom 33 died (11%), and 16 healthy volunteers who took 620 mg base chloroquine single doses. Whole blood concentrations of 13.5 µmol/L (95% credible interval 10.1-17.7) were associated with 1% mortality. Prolongation of ventricular depolarization is concentration-dependent with a QRS duration >150 msec independently highly predictive of mortality in chloroquine self-poisoning. Pharmacokinetic modeling predicts that most high dose regimens trialled in COVID-19 are unlikely to cause serious cardiovascular toxicity.


Hydroxychloroquine and chloroquine are closely-related drugs used for the treatment of malaria and rheumatological conditions, such as lupus. Laboratory tests have indicated that these drugs could also be used against the virus that causes COVID-19. Given the urgent need, these drugs have been fast-tracked into large-scale clinical trials, bypassing the usual stages that would provide estimates for suitable dosage. The dosage is a critical factor in a clinical trial: too low and the drug will not have an effect, too high and the side effects may counteract any potential benefits. Laboratory tests suggest that higher doses of chloroquine or hydroxychloroquine are needed for treating COVID-19 compared to malaria or lupus. However, there are concerns about the high doses used in some trials, as the drugs can have lethal side effects. Indeed, chloroquine has been used extensively in suicide attempts, particularly in France. To address these concerns, Watson et al. set out to determine the highest dosage of chloroquine (and thus of hydroxychloroquine, approximately) that does not cause unacceptable side effects. First, data was analysed regarding the concentration of chloroquine in the blood of 302 patients who had intentionally overdosed on the drug, since this concentration is tightly correlated with their risk of death. Watson et al. used a statistical model to calculate the maximal chloroquine concentration in a person's blood associated with a one per cent risk of death. This is taken to be the threshold above which any potential benefit of chloroquine treatment would be outweighed by the possibility of lethal toxicity. Watson et al. also estimated the relationship between chloroquine concentrations and changes in electrocardiogram patterns, which record the electrical activity of the heart. This makes it possible to determine whether a high dose of chloroquine has led to dangerous levels in the blood. Using a mathematical model of how chloroquine is metabolised, Watson et al. predicted that most of the trials that tested chloroquine as a treatment for COVID-19 did not reach the calculated threshold concentration. An exception was the CloroCovid-19 trial in Brazil, which was stopped early because people in the higher dosage group suffered more heart problems and died in greater numbers than those in the lower dosage group. Two large randomised trials, RECOVERY and SOLIDARITY, have shown no benefit of hydroxychloroquine or chloroquine in the treatment of COVID-19, changing clinical practice worldwide. Both of these trials used high doses resulting in higher hydroxychloroquine or chloroquine concentrations than normally observed in the treatment of malaria or rheumatological conditions. The results from Watson et al demonstrate that the lack of benefit seen in these two large clinical trials is not due to the drug dosage being too high.


Assuntos
Cloroquina/envenenamento , Overdose de Drogas/mortalidade , Tentativa de Suicídio , Suicídio , Adulto , Antimaláricos/administração & dosagem , Antimaláricos/envenenamento , Antimaláricos/uso terapêutico , Biotransformação , COVID-19 , Cloroquina/administração & dosagem , Cloroquina/efeitos adversos , Cloroquina/análogos & derivados , Cloroquina/sangue , Cloroquina/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Relação Dose-Resposta a Droga , Reposicionamento de Medicamentos , Eletrocardiografia , Feminino , Cardiopatias/induzido quimicamente , Cardiopatias/mortalidade , Humanos , Hidroxicloroquina/administração & dosagem , Hidroxicloroquina/efeitos adversos , Hidroxicloroquina/envenenamento , Hidroxicloroquina/uso terapêutico , Síndrome do QT Longo/induzido quimicamente , Malária/tratamento farmacológico , Masculino , Pandemias , Pneumonia Viral/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Medição de Risco , Tratamento Farmacológico da COVID-19
7.
Elife ; 92020 07 07.
Artigo em Inglês | MEDLINE | ID: covidwho-635520

RESUMO

Neither the disease mechanism nor treatments for COVID-19 are currently known. Here, we present a novel molecular mechanism for COVID-19 that provides therapeutic intervention points that can be addressed with existing FDA-approved pharmaceuticals. The entry point for the virus is ACE2, which is a component of the counteracting hypotensive axis of RAS. Bradykinin is a potent part of the vasopressor system that induces hypotension and vasodilation and is degraded by ACE and enhanced by the angiotensin1-9 produced by ACE2. Here, we perform a new analysis on gene expression data from cells in bronchoalveolar lavage fluid (BALF) from COVID-19 patients that were used to sequence the virus. Comparison with BALF from controls identifies a critical imbalance in RAS represented by decreased expression of ACE in combination with increases in ACE2, renin, angiotensin, key RAS receptors, kinogen and many kallikrein enzymes that activate it, and both bradykinin receptors. This very atypical pattern of the RAS is predicted to elevate bradykinin levels in multiple tissues and systems that will likely cause increases in vascular dilation, vascular permeability and hypotension. These bradykinin-driven outcomes explain many of the symptoms being observed in COVID-19.


In late 2019, a new virus named SARS-CoV-2, which causes a disease in humans called COVID-19, emerged in China and quickly spread around the world. Many individuals infected with the virus develop only mild, symptoms including a cough, high temperature and loss of sense of smell; while others may develop no symptoms at all. However, some individuals develop much more severe, life-threatening symptoms affecting the lungs and other parts of the body including the heart and brain. SARS-CoV-2 uses a human enzyme called ACE2 like a 'Trojan Horse' to sneak into the cells of its host. ACE2 lowers blood pressure in the human body and works against another enzyme known as ACE (which has the opposite effect). Therefore, the body has to balance the levels of ACE and ACE2 to maintain a normal blood pressure. It remains unclear whether SARS-CoV-2 affects how ACE2 and ACE work. When COVID-19 first emerged, a team of researchers in China studied fluid and cells collected from the lungs of patients to help them identify the SARS-CoV-2 virus. Here, Garvin et al. analyzed the data collected in the previous work to investigate whether changes in how the body regulates blood pressure may contribute to the life-threatening symptoms of COVID-19. The analyses found that SARS-CoV-2 caused the levels of ACE in the lung cells to decrease, while the levels of ACE2 increased. This in turn increased the levels of a molecule known as bradykinin in the cells (referred to as a 'Bradykinin Storm'). . Previous studies have shown that bradykinin induces pain and causes blood vessels to expand and become leaky which will lead to swelling and inflammation of the surrounding tissue. In addition, the analyses found that production of a substance called hyaluronic acid was increased and the enzymes that could degrade it greatly decreased. Hyaluronic acid can absorb more than 1,000 times its own weight in water to form a hydrogel. The Bradykinin-Storm-induced leakage of fluid into the lungs combined with the excess hyaluronic acid would likely result in a Jello-like substance that is preventing oxygen uptake and carbon dioxide release in the lungs of severely affected COVID-19 patients. Therefore, the findings of Garvin et al. suggest that the Bradykinin Storm may be responsible for the more severe symptoms of COVID-19. Further experiments identified several existing medicinal drugs that have the potential to be re-purposed to treat the Bradykinin Storm. A possible next step would be to carry out clinical trials to assess how effective these drugs are in treating patients with COVID-19. In addition, understanding how SARS-Cov-2 affects the body will help researchers and clinicians identify individuals who are most at risk of developing life-threatening symptoms.


Assuntos
Bradicinina/metabolismo , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/terapia , Pneumonia Viral/metabolismo , Pneumonia Viral/terapia , Sistema Renina-Angiotensina/fisiologia , Enzima de Conversão de Angiotensina 2 , Angiotensinas/metabolismo , Betacoronavirus/isolamento & purificação , Líquido da Lavagem Broncoalveolar/química , COVID-19 , Infecções por Coronavirus/genética , Infecções por Coronavirus/virologia , Feminino , Humanos , Masculino , Pandemias , Peptidil Dipeptidase A/biossíntese , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/genética , Pneumonia Viral/virologia , Renina/metabolismo , SARS-CoV-2 , Transcriptoma , Vasodilatação
8.
Elife ; 92020 07 07.
Artigo em Inglês | MEDLINE | ID: covidwho-635065

RESUMO

Understanding temporal dynamics of COVID-19 symptoms could provide fine-grained resolution to guide clinical decision-making. Here, we use deep neural networks over an institution-wide platform for the augmented curation of clinical notes from 77,167 patients subjected to COVID-19 PCR testing. By contrasting Electronic Health Record (EHR)-derived symptoms of COVID-19-positive (COVIDpos; n = 2,317) versus COVID-19-negative (COVIDneg; n = 74,850) patients for the week preceding the PCR testing date, we identify anosmia/dysgeusia (27.1-fold), fever/chills (2.6-fold), respiratory difficulty (2.2-fold), cough (2.2-fold), myalgia/arthralgia (2-fold), and diarrhea (1.4-fold) as significantly amplified in COVIDpos over COVIDneg patients. The combination of cough and fever/chills has 4.2-fold amplification in COVIDpos patients during the week prior to PCR testing, in addition to anosmia/dysgeusia, constitutes the earliest EHR-derived signature of COVID-19. This study introduces an Augmented Intelligence platform for the real-time synthesis of institutional biomedical knowledge. The platform holds tremendous potential for scaling up curation throughput, thus enabling EHR-powered early disease diagnosis.


Assuntos
Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Adulto , Betacoronavirus/isolamento & purificação , COVID-19 , Teste para COVID-19 , Calafrios/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/fisiopatologia , Infecções por Coronavirus/virologia , Diarreia/virologia , Disgeusia/virologia , Feminino , Febre/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Mialgia/virologia , Transtornos do Olfato/virologia , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/fisiopatologia , Pneumonia Viral/virologia , Reação em Cadeia da Polimerase , SARS-CoV-2
9.
Elife ; 92020 06 19.
Artigo em Inglês | MEDLINE | ID: covidwho-607959

RESUMO

Previously, we showed that 3% (31/1032)of asymptomatic healthcare workers (HCWs) from a large teaching hospital in Cambridge, UK, tested positive for SARS-CoV-2 in April 2020. About 15% (26/169) HCWs with symptoms of coronavirus disease 2019 (COVID-19) also tested positive for SARS-CoV-2 (Rivett et al., 2020). Here, we show that the proportion of both asymptomatic and symptomatic HCWs testing positive for SARS-CoV-2 rapidly declined to near-zero between 25th April and 24th May 2020, corresponding to a decline in patient admissions with COVID-19 during the ongoing UK 'lockdown'. These data demonstrate how infection prevention and control measures including staff testing may help prevent hospitals from becoming independent 'hubs' of SARS-CoV-2 transmission, and illustrate how, with appropriate precautions, organizations in other sectors may be able to resume on-site work safely.


Assuntos
Técnicas de Laboratório Clínico/estatística & dados numéricos , Infecções por Coronavirus/transmissão , Pessoal de Saúde , Programas de Rastreamento/estatística & dados numéricos , Doenças Profissionais/prevenção & controle , Pandemias , Pneumonia Viral/transmissão , Adulto , Doenças Assintomáticas , Betacoronavirus/genética , Betacoronavirus/isolamento & purificação , COVID-19 , Teste para COVID-19 , Infecções Comunitárias Adquiridas/transmissão , Busca de Comunicante , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Transmissão de Doença Infecciosa/prevenção & controle , Inglaterra/epidemiologia , Características da Família , Feminino , Unidades Hospitalares , Hospitais de Ensino/organização & administração , Hospitais de Ensino/estatística & dados numéricos , Hospitais Universitários/organização & administração , Hospitais Universitários/estatística & dados numéricos , Humanos , Controle de Infecções , Transmissão de Doença Infecciosa do Paciente para o Profissional/estatística & dados numéricos , Masculino , Programas de Rastreamento/organização & administração , Pessoa de Meia-Idade , Nasofaringe/virologia , Doenças Profissionais/epidemiologia , Pandemias/prevenção & controle , Admissão do Paciente/estatística & dados numéricos , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Prevalência , Avaliação de Programas e Projetos de Saúde , Reação em Cadeia da Polimerase em Tempo Real , SARS-CoV-2 , Avaliação de Sintomas
10.
Elife ; 92020 05 28.
Artigo em Inglês | MEDLINE | ID: covidwho-401507

RESUMO

The COVID-19 pandemic demands assimilation of all biomedical knowledge to decode mechanisms of pathogenesis. Despite the recent renaissance in neural networks, a platform for the real-time synthesis of the exponentially growing biomedical literature and deep omics insights is unavailable. Here, we present the nferX platform for dynamic inference from over 45 quadrillion possible conceptual associations from unstructured text, and triangulation with insights from single-cell RNA-sequencing, bulk RNA-seq and proteomics from diverse tissue types. A hypothesis-free profiling of ACE2 suggests tongue keratinocytes, olfactory epithelial cells, airway club cells and respiratory ciliated cells as potential reservoirs of the SARS-CoV-2 receptor. We find the gut as the putative hotspot of COVID-19, where a maturation correlated transcriptional signature is shared in small intestine enterocytes among coronavirus receptors (ACE2, DPP4, ANPEP). A holistic data science platform triangulating insights from structured and unstructured data holds potential for accelerating the generation of impactful biological insights and hypotheses.


Assuntos
Infecções por Coronavirus/virologia , Bibliotecas Médicas , Pneumonia Viral/virologia , Receptores Virais/metabolismo , Animais , Betacoronavirus/genética , Betacoronavirus/metabolismo , COVID-19 , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/patologia , Perfilação da Expressão Gênica , Humanos , Descoberta do Conhecimento , Camundongos , Pandemias , Pneumonia Viral/metabolismo , Pneumonia Viral/patologia , Receptores de Coronavírus , Receptores Virais/química , Receptores Virais/genética , SARS-CoV-2
11.
Elife ; 92020 05 26.
Artigo em Inglês | MEDLINE | ID: covidwho-378182

RESUMO

Molecular mimicry is an evolutionary strategy adopted by viruses to exploit the host cellular machinery. We report that SARS-CoV-2 has evolved a unique S1/S2 cleavage site, absent in any previous coronavirus sequenced, resulting in the striking mimicry of an identical FURIN-cleavable peptide on the human epithelial sodium channel α-subunit (ENaC-α). Genetic alteration of ENaC-α causes aldosterone dysregulation in patients, highlighting that the FURIN site is critical for activation of ENaC. Single cell RNA-seq from 66 studies shows significant overlap between expression of ENaC-α and the viral receptor ACE2 in cell types linked to the cardiovascular-renal-pulmonary pathophysiology of COVID-19. Triangulating this cellular characterization with cleavage signatures of 178 proteases highlights proteolytic degeneracy wired into the SARS-CoV-2 lifecycle. Evolution of SARS-CoV-2 into a global pandemic may be driven in part by its targeted mimicry of ENaC-α, a protein critical for the homeostasis of airway surface liquid, whose misregulation is associated with respiratory conditions.


Viruses hijack the cellular machinery of humans to infect their cells and multiply. The virus causing the global COVID-19 pandemic, SARS-CoV-2, is no exception. Identifying which proteins in human cells the virus co-opts is crucial for developing new ways to diagnose, prevent and treat COVID-19 infections. SARS-CoV-2 is covered in spike-shaped proteins, which the virus uses to gain entry into cells. First, the spikes bind to a protein called ACE2, which is found on the cells that line the respiratory tract and lungs. SARS-CoV-2 then exploits enzymes called proteases to cut, or cleave, its spikes at a specific site which allows the virus to infiltrate the host cell. Proteases identify which proteins to target based on the sequence of amino acids ­ the building blocks of proteins ­ at the cleavage site. However, it remained unclear which human proteases SARS-CoV-2 co-opts and whether its cut site is similar to human proteins. Now, Anand et al. show that the spike proteins on SARS-CoV-2 may have the same sequence of amino acids at its cut site as a human epithelial channel protein called ENaC-α. This channel is important for maintaining the balance of salt and water in many organs including the lungs. Further analyses showed that ENaC-α is often found in the same types of human lung and respiratory tract cells as ACE2. This suggests that SARS-CoV-2 may use the same proteases that cut ENaC-α to get inside human respiratory cells. It is possible that by hijacking the cutting mechanism for ENaC-α, SARS-CoV-2 interferes with the balance of salt and water in the lungs of COVID-19 patients. This may help explain why the virus causes severe respiratory symptoms. However, more studies are needed to confirm that the proteases that cut ENaC-α also cut the spike proteins on SARS-CoV-2, and how this affects the respiratory health of COVID-19 patients.


Assuntos
Betacoronavirus/metabolismo , Infecções por Coronavirus/virologia , Canais Epiteliais de Sódio/metabolismo , Mimetismo Molecular , Peptídeo Hidrolases/metabolismo , Pneumonia Viral/virologia , Proteínas do Envelope Viral/metabolismo , Proteínas Virais/metabolismo , Enzima de Conversão de Angiotensina 2 , Betacoronavirus/genética , Betacoronavirus/patogenicidade , COVID-19 , Canais Epiteliais de Sódio/genética , Interações Hospedeiro-Patógeno , Humanos , Pandemias , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Proteólise , SARS-CoV-2 , Especificidade por Substrato , Proteínas do Envelope Viral/genética , Proteínas Virais/genética
12.
Elife ; 92020 05 12.
Artigo em Inglês | MEDLINE | ID: covidwho-245716

RESUMO

Platelets are anucleate cells in blood whose principal function is to stop bleeding by forming aggregates for hemostatic reactions. In addition to their participation in physiological hemostasis, platelet aggregates are also involved in pathological thrombosis and play an important role in inflammation, atherosclerosis, and cancer metastasis. The aggregation of platelets is elicited by various agonists, but these platelet aggregates have long been considered indistinguishable and impossible to classify. Here we present an intelligent method for classifying them by agonist type. It is based on a convolutional neural network trained by high-throughput imaging flow cytometry of blood cells to identify and differentiate subtle yet appreciable morphological features of platelet aggregates activated by different types of agonists. The method is a powerful tool for studying the underlying mechanism of platelet aggregation and is expected to open a window on an entirely new class of clinical diagnostics, pharmacometrics, and therapeutics.


Platelets are small cells in the blood that primarily help stop bleeding after an injury by sticking together with other blood cells to form a clot that seals the broken blood vessel. Blood clots, however, can sometimes cause harm. For example, if a clot blocks the blood flow to the heart or the brain, it can result in a heart attack or stroke, respectively. Blood clots have also been linked to harmful inflammation and the spread of cancer, and there are now preliminary reports of remarkably high rates of clotting in COVID-19 patients in intensive care units. A variety of chemicals can cause platelets to stick together. It has long been assumed that it would be impossible to tell apart the clots formed by different chemicals (which are also known as agonists). This is largely because these aggregates all look very similar under a microscope, making it incredibly time consuming for someone to look at enough microscopy images to reliably identify the subtle differences between them. However, finding a way to distinguish the different types of platelet aggregates could lead to better ways to diagnose or treat blood vessel-clogging diseases. To make this possible, Zhou, Yasumoto et al. have developed a method called the "intelligent platelet aggregate classifier" or iPAC for short. First, numerous clot-causing chemicals were added to separate samples of platelets taken from healthy human blood. The method then involved using high-throughput techniques to take thousands of images of these samples. Then, a sophisticated computer algorithm called a deep learning model analyzed the resulting image dataset and "learned" to distinguish the chemical causes of the platelet aggregates based on subtle differences in their shapes. Finally, Zhou, Yasumoto et al. verified iPAC method's accuracy using a new set of human platelet samples. The iPAC method may help scientists studying the steps that lead to clot formation. It may also help clinicians distinguish which clot-causing chemical led to a patient's heart attack or stroke. This could help them choose whether aspirin or another anti-platelet drug would be the best treatment. But first more studies are needed to confirm whether this method is a useful tool for drug selection or diagnosis.


Assuntos
Redes Neurais de Computação , Agregação Plaquetária , Citometria de Fluxo , Humanos , Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas , Ativação Plaquetária , Trombose/classificação
13.
Elife ; 92020 05 11.
Artigo em Inglês | MEDLINE | ID: covidwho-236326

RESUMO

Significant differences exist in the availability of healthcare worker (HCW) SARS-CoV-2 testing between countries, and existing programmes focus on screening symptomatic rather than asymptomatic staff. Over a 3 week period (April 2020), 1032 asymptomatic HCWs were screened for SARS-CoV-2 in a large UK teaching hospital. Symptomatic staff and symptomatic household contacts were additionally tested. Real-time RT-PCR was used to detect viral RNA from a throat+nose self-swab. 3% of HCWs in the asymptomatic screening group tested positive for SARS-CoV-2. 17/30 (57%) were truly asymptomatic/pauci-symptomatic. 12/30 (40%) had experienced symptoms compatible with coronavirus disease 2019 (COVID-19)>7 days prior to testing, most self-isolating, returning well. Clusters of HCW infection were discovered on two independent wards. Viral genome sequencing showed that the majority of HCWs had the dominant lineage B∙1. Our data demonstrates the utility of comprehensive screening of HCWs with minimal or no symptoms. This approach will be critical for protecting patients and hospital staff.


Patients admitted to NHS hospitals are now routinely screened for SARS-CoV-2 (the virus that causes COVID-19), and isolated from other patients if necessary. Yet healthcare workers, including frontline patient-facing staff such as doctors, nurses and physiotherapists, are only tested and excluded from work if they develop symptoms of the illness. However, there is emerging evidence that many people infected with SARS-CoV-2 never develop significant symptoms: these people will therefore be missed by 'symptomatic-only' testing. There is also important data showing that around half of all transmissions of SARS-CoV-2 happen before the infected individual even develops symptoms. This means that much broader testing programs are required to spot people when they are most infectious. Rivett, Sridhar, Sparkes, Routledge et al. set out to determine what proportion of healthcare workers was infected with SARS-CoV-2 while also feeling generally healthy at the time of testing. Over 1,000 staff members at a large UK hospital who felt they were well enough to work, and did not fit the government criteria for COVID-19 infection, were tested. Amongst these, 3% were positive for SARS-CoV-2. On closer questioning, around one in five reported no symptoms, two in five very mild symptoms that they had dismissed as inconsequential, and a further two in five reported COVID-19 symptoms that had stopped more than a week previously. In parallel, healthcare workers with symptoms of COVID-19 (and their household contacts) who were self-isolating were also tested, in order to allow those without the virus to quickly return to work and bolster a stretched workforce. Finally, the rates of infection were examined to probe how the virus could have spread through the hospital and among staff ­ and in particular, to understand whether rates of infection were greater among staff working in areas devoted to COVID-19 patients. Despite wearing appropriate personal protective equipment, healthcare workers in these areas were almost three times more likely to test positive than those working in areas without COVID-19 patients. However, it is not clear whether this genuinely reflects greater rates of patients passing the infection to staff. Staff may give the virus to each other, or even acquire it at home. Overall, this work implies that hospitals need to be vigilant and introduce broad screening programmes across their workforces. It will be vital to establish such approaches before 'lockdown' is fully lifted, so healthcare institutions are prepared for any second peak of infections.


Assuntos
Infecções Assintomáticas , Técnicas de Laboratório Clínico , Pessoal de Saúde , Betacoronavirus/fisiologia , COVID-19 , Teste para COVID-19 , Vacinas contra COVID-19 , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Feminino , Humanos , Controle de Infecções , Masculino , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Reação em Cadeia da Polimerase em Tempo Real , SARS-CoV-2 , Reino Unido/epidemiologia
14.
Elife ; 92020 04 06.
Artigo em Inglês | MEDLINE | ID: covidwho-38616

RESUMO

The discovery of angiotensin converting enzyme-2 (ACE-2) as the receptor for SARS- CoV-2 (Severe Acute Respiratory Syndrome Coronavirus-2) has implicated the renin-angiotensin-aldosterone system in acute respiratory distress syndrome (ARDS) and respiratory failure in patients with coronavirus disease-19 (COVID-19). The angiotensin converting enzyme-1-angiotensin II-angiotensin AT1 receptor pathway contributes to the pathophysiology of ARDS, whereas activation of the ACE-2-angiotensin(1-7)-angiotensin AT2 receptor and the ACE-2-angiotensin(1-7)-Mas receptor pathways have been shown to be protective. Here we propose and discuss therapeutic considerations how to increase soluble ACE-2 in plasma in order for ACE-2 to capture and thereby inactivate SARS-CoV-2. This could be achieved by administering recombinant soluble ACE-2. We also discuss why and how ACEIs and ARBs provide cardiovascular, renal and also pulmonary protection in SARS-CoV-2- associated ARDS. Discontinuing these medications in COVID-19 patients may therefore potentially be harmful.


Assuntos
Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/tratamento farmacológico , Antagonistas de Receptores de Angiotensina/farmacologia , Enzima de Conversão de Angiotensina 2 , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Betacoronavirus , COVID-19 , Infecções por Coronavirus/epidemiologia , Pulmão/metabolismo , Pulmão/virologia , Pandemias , Pneumonia Viral/epidemiologia , Substâncias Protetoras/uso terapêutico , Sistema Renina-Angiotensina/efeitos dos fármacos , SARS-CoV-2
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