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1.
Nature ; 615(7950): 143-150, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36630998

RESUMO

The SARS-CoV-2 Omicron variant is more immune evasive and less virulent than other major viral variants that have so far been recognized1-12. The Omicron spike (S) protein, which has an unusually large number of mutations, is considered to be the main driver of these phenotypes. Here we generated chimeric recombinant SARS-CoV-2 encoding the S gene of Omicron (BA.1 lineage) in the backbone of an ancestral SARS-CoV-2 isolate, and compared this virus with the naturally circulating Omicron variant. The Omicron S-bearing virus robustly escaped vaccine-induced humoral immunity, mainly owing to mutations in the receptor-binding motif; however, unlike naturally occurring Omicron, it efficiently replicated in cell lines and primary-like distal lung cells. Similarly, in K18-hACE2 mice, although virus bearing Omicron S caused less severe disease than the ancestral virus, its virulence was not attenuated to the level of Omicron. Further investigation showed that mutating non-structural protein 6 (nsp6) in addition to the S protein was sufficient to recapitulate the attenuated phenotype of Omicron. This indicates that although the vaccine escape of Omicron is driven by mutations in S, the pathogenicity of Omicron is determined by mutations both in and outside of the S protein.


Assuntos
COVID-19 , Proteínas do Nucleocapsídeo de Coronavírus , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Fatores de Virulência , Virulência , Animais , Camundongos , Linhagem Celular , Evasão da Resposta Imune , SARS-CoV-2/imunologia , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Proteínas do Nucleocapsídeo de Coronavírus/genética , Proteínas do Nucleocapsídeo de Coronavírus/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Humanos , Vacinas contra COVID-19/imunologia , Pulmão/citologia , Pulmão/virologia , Replicação Viral , Mutação
2.
Nature ; 615(7954): 858-865, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36949201

RESUMO

Human society is dependent on nature1,2, but whether our ecological foundations are at risk remains unknown in the absence of systematic monitoring of species' populations3. Knowledge of species fluctuations is particularly inadequate in the marine realm4. Here we assess the population trends of 1,057 common shallow reef species from multiple phyla at 1,636 sites around Australia over the past decade. Most populations decreased over this period, including many tropical fishes, temperate invertebrates (particularly echinoderms) and southwestern Australian macroalgae, whereas coral populations remained relatively stable. Population declines typically followed heatwave years, when local water temperatures were more than 0.5 °C above temperatures in 2008. Following heatwaves5,6, species abundances generally tended to decline near warm range edges, and increase near cool range edges. More than 30% of shallow invertebrate species in cool latitudes exhibited high extinction risk, with rapidly declining populations trapped by deep ocean barriers, preventing poleward retreat as temperatures rise. Greater conservation effort is needed to safeguard temperate marine ecosystems, which are disproportionately threatened and include species with deep evolutionary roots. Fundamental among such efforts, and broader societal needs to efficiently adapt to interacting anthropogenic and natural pressures, is greatly expanded monitoring of species' population trends7,8.


Assuntos
Antozoários , Recifes de Corais , Calor Extremo , Peixes , Aquecimento Global , Invertebrados , Oceanos e Mares , Água do Mar , Alga Marinha , Animais , Austrália , Peixes/classificação , Invertebrados/classificação , Aquecimento Global/estatística & dados numéricos , Alga Marinha/classificação , Dinâmica Populacional , Densidade Demográfica , Água do Mar/análise , Extinção Biológica , Conservação dos Recursos Naturais/tendências , Equinodermos/classificação
3.
N Engl J Med ; 386(19): 1781-1792, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35363951

RESUMO

BACKGROUND: The benefits and safety of the treatment of mild chronic hypertension (blood pressure, <160/100 mm Hg) during pregnancy are uncertain. Data are needed on whether a strategy of targeting a blood pressure of less than 140/90 mm Hg reduces the incidence of adverse pregnancy outcomes without compromising fetal growth. METHODS: In this open-label, multicenter, randomized trial, we assigned pregnant women with mild chronic hypertension and singleton fetuses at a gestational age of less than 23 weeks to receive antihypertensive medications recommended for use in pregnancy (active-treatment group) or to receive no such treatment unless severe hypertension (systolic pressure, ≥160 mm Hg; or diastolic pressure, ≥105 mm Hg) developed (control group). The primary outcome was a composite of preeclampsia with severe features, medically indicated preterm birth at less than 35 weeks' gestation, placental abruption, or fetal or neonatal death. The safety outcome was small-for-gestational-age birth weight below the 10th percentile for gestational age. Secondary outcomes included composites of serious neonatal or maternal complications, preeclampsia, and preterm birth. RESULTS: A total of 2408 women were enrolled in the trial. The incidence of a primary-outcome event was lower in the active-treatment group than in the control group (30.2% vs. 37.0%), for an adjusted risk ratio of 0.82 (95% confidence interval [CI], 0.74 to 0.92; P<0.001). The percentage of small-for-gestational-age birth weights below the 10th percentile was 11.2% in the active-treatment group and 10.4% in the control group (adjusted risk ratio, 1.04; 95% CI, 0.82 to 1.31; P = 0.76). The incidence of serious maternal complications was 2.1% and 2.8%, respectively (risk ratio, 0.75; 95% CI, 0.45 to 1.26), and the incidence of severe neonatal complications was 2.0% and 2.6% (risk ratio, 0.77; 95% CI, 0.45 to 1.30). The incidence of any preeclampsia in the two groups was 24.4% and 31.1%, respectively (risk ratio, 0.79; 95% CI, 0.69 to 0.89), and the incidence of preterm birth was 27.5% and 31.4% (risk ratio, 0.87; 95% CI, 0.77 to 0.99). CONCLUSIONS: In pregnant women with mild chronic hypertension, a strategy of targeting a blood pressure of less than 140/90 mm Hg was associated with better pregnancy outcomes than a strategy of reserving treatment only for severe hypertension, with no increase in the risk of small-for-gestational-age birth weight. (Funded by the National Heart, Lung, and Blood Institute; CHAP ClinicalTrials.gov number, NCT02299414.).


Assuntos
Anti-Hipertensivos/uso terapêutico , Hipertensão Induzida pela Gravidez/tratamento farmacológico , Hipertensão , Resultado da Gravidez , Descolamento Prematuro da Placenta/epidemiologia , Descolamento Prematuro da Placenta/prevenção & controle , Peso ao Nascer , Doença Crônica , Feminino , Retardo do Crescimento Fetal/epidemiologia , Retardo do Crescimento Fetal/prevenção & controle , Humanos , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Recém-Nascido , Pré-Eclâmpsia/epidemiologia , Pré-Eclâmpsia/prevenção & controle , Gravidez , Resultado da Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/prevenção & controle
4.
Am J Hum Genet ; 108(9): 1765-1779, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34450030

RESUMO

An important goal of clinical genomics is to be able to estimate the risk of adverse disease outcomes. Between 5% and 10% of individuals with ulcerative colitis (UC) require colectomy within 5 years of diagnosis, but polygenic risk scores (PRSs) utilizing findings from genome-wide association studies (GWASs) are unable to provide meaningful prediction of this adverse status. By contrast, in Crohn disease, gene expression profiling of GWAS-significant genes does provide some stratification of risk of progression to complicated disease in the form of a transcriptional risk score (TRS). Here, we demonstrate that a measured TRS based on bulk rectal gene expression in the PROTECT inception cohort study has a positive predictive value approaching 50% for colectomy. Single-cell profiling demonstrates that the genes are active in multiple diverse cell types from both the epithelial and immune compartments. Expression quantitative trait locus (QTL) analysis identifies genes with differential effects at baseline and week 52 follow-up, but for the most part, differential expression associated with colectomy risk is independent of local genetic regulation. Nevertheless, a predicted polygenic transcriptional risk score (PPTRS) derived by summation of transcriptome-wide association study (TWAS) effects identifies UC-affected individuals at 5-fold elevated risk of colectomy with data from the UK Biobank population cohort studies, independently replicated in an NIDDK-IBDGC dataset. Prediction of gene expression from relatively small transcriptome datasets can thus be used in conjunction with TWASs for stratification of risk of disease complications.


Assuntos
Colectomia/estatística & dados numéricos , Colite Ulcerativa/cirurgia , Doença de Crohn/cirurgia , Locos de Características Quantitativas , Transcriptoma , Bancos de Espécimes Biológicos , Estudos de Coortes , Colite Ulcerativa/complicações , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/genética , Colo/metabolismo , Colo/patologia , Colo/cirurgia , Doença de Crohn/complicações , Doença de Crohn/diagnóstico , Doença de Crohn/genética , Conjuntos de Dados como Assunto , Progressão da Doença , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Herança Multifatorial , Prognóstico , Medição de Risco , Reino Unido
5.
Virol J ; 21(1): 105, 2024 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-38715113

RESUMO

BACKGROUND: The factors contributing to the accelerated convergent evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are not fully understood. Unraveling the contribution of viral replication in immunocompromised patients is important for the early detection of novel mutations and developing approaches to limit COVID-19. METHODS: We deep sequenced SARS-CoV-2 RNA from 192 patients (64% hospitalized, 39% immunosuppressed) and compared the viral genetic diversity within the patient groups of different immunity and hospitalization status. Serial sampling of 14 patients was evaluated for viral evolution in response to antiviral treatments. RESULTS: We identified hospitalized and immunosuppressed patients with significantly higher levels of viral genetic diversity and variability. Further evaluation of serial samples revealed accumulated mutations associated with escape from neutralizing antibodies in a subset of the immunosuppressed patients treated with antiviral therapies. Interestingly, the accumulated viral mutations that arose in this early Omicron wave, which were not common in the patient viral lineages, represent convergent mutations that are prevalent in the later Omicron sublineages, including the XBB, BA.2.86.1 and its descendent JN sublineages. CONCLUSIONS: Our results illustrate the importance of identifying convergent mutations generated during antiviral therapy in immunosuppressed patients, as they may contribute to the future evolutionary landscape of SARS-CoV-2. Our study also provides evidence of a correlation between SARS-CoV-2 convergent mutations and specific antiviral treatments. Evaluating high-confidence genomes from distinct waves in the pandemic with detailed patient metadata allows for discerning of convergent mutations that contribute to the ongoing evolution of SARS-CoV-2.


Assuntos
Antivirais , COVID-19 , Evolução Molecular , Hospedeiro Imunocomprometido , Mutação , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Antivirais/uso terapêutico , COVID-19/virologia , COVID-19/imunologia , Masculino , Feminino , Pessoa de Meia-Idade , Anticorpos Neutralizantes/imunologia , Idoso , Adulto , RNA Viral/genética , Tratamento Farmacológico da COVID-19 , Variação Genética , Filogenia
6.
Prev Sci ; 25(2): 369-379, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38321316

RESUMO

Researchers are increasingly using web-based technologies to deliver family-based, prevention programming. Few studies have examined the success of such approaches for families with low incomes. The purpose of this study was to describe the level of in-class and online engagement in a childhood obesity prevention program for parents with low incomes, to examine the demographic correlates of parent engagement, and to examine dosage effects on parental feeding outcomes as a function of online exposure. All participants attended in-class nutrition education classes (Eating Smart · Being Active) as part of the Expanded Food and Nutrition Education Program (EFNEP) in Colorado and Washington State (classes were offered in English and Spanish). Participants in this analysis were 168 parents from a larger cluster randomized controlled trial who had been randomly assigned to also receive a newly developed, mobile-based version of an efficacious, feeding-focused, childhood obesity prevention program. Results showed that despite high levels of in-person attendance (70%), participants only accessed 47% of the videos (online content). Older parents and parents of girls showed higher levels of in-person attendance; currently employed parents showed lower levels. Online engagement varied as a function of ethnicity and acculturation: non-Hispanic parents accessed the most videos, low-acculturated Hispanic parents accessed the second most, and highly acculturated Hispanic parents accessed the least. In contrast, low-acculturated Hispanic parents showed the highest in-person attendance. For all but one outcome, significant online program effects were found only for parents who accessed at least half of the videos. Implications for mobile-based, family-based prevention programs for parents with low incomes are considered.ClinicalTrials.gov Identifier: NCT03170700; Registration Date: March 08, 2017.


Assuntos
Obesidade Infantil , Criança , Feminino , Humanos , Educação em Saúde , Poder Familiar , Pais/educação , Obesidade Infantil/prevenção & controle , Pobreza , Washington , Hispânico ou Latino
7.
J Infect Dis ; 228(4): 412-421, 2023 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-36808252

RESUMO

BACKGROUND: Kawasaki disease (KD) is a febrile illness of young childhood that can result in coronary artery aneurysms and death. Coronavirus disease 2019 (COVID-19) mitigation strategies resulted in a marked decrease in KD cases worldwide, supporting a transmissible respiratory agent as the cause. We previously reported a peptide epitope recognized by monoclonal antibodies (MAbs) derived from clonally expanded peripheral blood plasmablasts from 3 of 11 KD children, suggesting a common disease trigger in a subset of patients with KD. METHODS: We performed amino acid substitution scans to develop modified peptides with improved recognition by KD MAbs. We prepared additional MAbs from KD peripheral blood plasmablasts and assessed MAb characteristics that were associated with binding to the modified peptides. RESULTS: We report a modified peptide epitope that is recognized by 20 MAbs from 11 of 12 KD patients. These MAbs predominantly use heavy chain VH3-74; two-thirds of VH3-74 plasmablasts from these patients recognize the epitope. The MAbs were nonidentical between patients but share a common complementarity-determining region 3 (CDR3) motif. CONCLUSIONS: These results demonstrate a convergent VH3-74 plasmablast response to a specific protein antigen in children with KD, supporting one predominant causative agent in the etiopathogenesis of the illness.


Assuntos
COVID-19 , Síndrome de Linfonodos Mucocutâneos , Humanos , Criança , Epitopos , Formação de Anticorpos , Anticorpos Monoclonais , Peptídeos
8.
Nat Immunol ; 12(2): 137-43, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21217758

RESUMO

The 5' cap structures of higher eukaryote mRNAs have ribose 2'-O-methylation. Likewise, many viruses that replicate in the cytoplasm of eukaryotes have evolved 2'-O-methyltransferases to autonomously modify their mRNAs. However, a defined biological role for 2'-O-methylation of mRNA remains elusive. Here we show that 2'-O-methylation of viral mRNA was critically involved in subverting the induction of type I interferon. We demonstrate that human and mouse coronavirus mutants lacking 2'-O-methyltransferase activity induced higher expression of type I interferon and were highly sensitive to type I interferon. Notably, the induction of type I interferon by viruses deficient in 2'-O-methyltransferase was dependent on the cytoplasmic RNA sensor Mda5. This link between Mda5-mediated sensing of viral RNA and 2'-O-methylation of mRNA suggests that RNA modifications such as 2'-O-methylation provide a molecular signature for the discrimination of self and non-self mRNA.


Assuntos
Infecções por Coronavirus/metabolismo , Coronavirus/fisiologia , RNA Helicases DEAD-box/metabolismo , Metiltransferases/metabolismo , Proteínas Virais/metabolismo , Animais , Linhagem Celular , Coronavirus/patogenicidade , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/imunologia , Humanos , Imunidade Inata/genética , Interferon Tipo I/genética , Interferon Tipo I/imunologia , Interferon Tipo I/metabolismo , Helicase IFIH1 Induzida por Interferon , Metilação , Metiltransferases/genética , Metiltransferases/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Viral/metabolismo , Receptor de Interferon alfa e beta/genética , Receptores de Reconhecimento de Padrão/genética , Ribose/metabolismo , Proteínas Virais/genética , Proteínas Virais/imunologia , Virulência/genética , Replicação Viral/genética
9.
Proc Natl Acad Sci U S A ; 117(14): 8094-8103, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32198201

RESUMO

Coronaviruses (CoVs) are positive-sense RNA viruses that can emerge from endemic reservoirs and infect zoonotically, causing significant morbidity and mortality. CoVs encode an endoribonuclease designated EndoU that facilitates evasion of host pattern recognition receptor MDA5, but the target of EndoU activity was not known. Here, we report that EndoU cleaves the 5'-polyuridines from negative-sense viral RNA, termed PUN RNA, which is the product of polyA-templated RNA synthesis. Using a virus containing an EndoU catalytic-inactive mutation, we detected a higher abundance of PUN RNA in the cytoplasm compared to wild-type-infected cells. Furthermore, we found that transfecting PUN RNA into cells stimulates a robust, MDA5-dependent interferon response, and that removal of the polyuridine extension on the RNA dampens the response. Overall, the results of this study reveal the PUN RNA to be a CoV MDA5-dependent pathogen-associated molecular pattern (PAMP). We also establish a mechanism for EndoU activity to cleave and limit the accumulation of this PAMP. Since EndoU activity is highly conserved in all CoVs, inhibiting this activity may serve as an approach for therapeutic interventions against existing and emerging CoV infections.


Assuntos
Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Coronavirus/metabolismo , Endorribonucleases/metabolismo , Poli U/metabolismo , Proteínas não Estruturais Virais/metabolismo , Animais , Antivirais/farmacologia , Linhagem Celular , Chlorocebus aethiops , Coronavirus/enzimologia , Coronavirus/imunologia , Endorribonucleases/genética , Interações entre Hospedeiro e Microrganismos/fisiologia , Humanos , Interferons/farmacologia , Poli U/química , RNA Viral/genética , RNA Viral/metabolismo , Uridina/química , Células Vero , Proteínas não Estruturais Virais/genética , Replicação Viral/fisiologia
10.
J Virol ; 95(19): e0086221, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34260266

RESUMO

SARS-CoV-2 can infect multiple organs, including lung, intestine, kidney, heart, liver, and brain. The molecular details of how the virus navigates through diverse cellular environments and establishes replication are poorly defined. Here, we generated a panel of phenotypically diverse, SARS-CoV-2-infectible human cell lines representing different body organs and performed longitudinal survey of cellular proteins and pathways broadly affected by the virus. This revealed universal inhibition of interferon signaling across cell types following SARS-CoV-2 infection. We performed systematic analyses of the JAK-STAT pathway in a broad range of cellular systems, including immortalized cells and primary-like cardiomyocytes, and found that SARS-CoV-2 targeted the proximal pathway components, including Janus kinase 1 (JAK1), tyrosine kinase 2 (Tyk2), and the interferon receptor subunit 1 (IFNAR1), resulting in cellular desensitization to type I IFN. Detailed mechanistic investigation of IFNAR1 showed that the protein underwent ubiquitination upon SARS-CoV-2 infection. Furthermore, chemical inhibition of JAK kinases enhanced infection of stem cell-derived cultures, indicating that the virus benefits from inhibiting the JAK-STAT pathway. These findings suggest that the suppression of interferon signaling is a mechanism widely used by the virus to evade antiviral innate immunity, and that targeting the viral mediators of immune evasion may help block virus replication in patients with COVID-19. IMPORTANCE SARS-CoV-2 can infect various organs in the human body, but the molecular interface between the virus and these organs remains unexplored. In this study, we generated a panel of highly infectible human cell lines originating from various body organs and employed these cells to identify cellular processes commonly or distinctly disrupted by SARS-CoV-2 in different cell types. One among the universally impaired processes was interferon signaling. Systematic analysis of this pathway in diverse culture systems showed that SARS-CoV-2 targets the proximal JAK-STAT pathway components, destabilizes the type I interferon receptor though ubiquitination, and consequently renders the infected cells resistant to type I interferon. These findings illuminate how SARS-CoV-2 can continue to propagate in different tissues even in the presence of a disseminated innate immune response.


Assuntos
COVID-19/metabolismo , Interações entre Hospedeiro e Microrganismos/fisiologia , Janus Quinases/metabolismo , SARS-CoV-2/metabolismo , Linhagem Celular , Regulação da Expressão Gênica , Humanos , Evasão da Resposta Imune , Imunidade Inata , Interferon Tipo I/metabolismo , Janus Quinase 1/metabolismo , Miócitos Cardíacos , Receptor de Interferon alfa e beta/metabolismo , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais , TYK2 Quinase/metabolismo , Replicação Viral
11.
Crit Care Nurs Q ; 45(4): 290-299, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35980790

RESUMO

Despite the many advancements in infection prevention, catheter-associated urinary tract infections (CAUTI) continue to be problematic for many hospitals. The large urban teaching hospital featured in this article developed a team that consisted of a registered nurse quality Lean coach, bedside nurses from each inpatient nursing unit, physicians, an infection prevention specialist nurse, an education specialist nurse, and members of the quality department to study this matter. The team focused on understanding current practice related to the use and duration of indwelling urinary catheters. It was discovered that while some indwelling urinary catheters were justified, others could have been avoided altogether or removed earlier. Multifaceted measures were instituted at this hospital to decrease indwelling urinary catheter days and reduce CAUTI rates. The team's journey to successfully decreasing indwelling urinary catheter days by 19.79% and CAUTI rates by 38% is highlighted.


Assuntos
Infecções Relacionadas a Cateter , Infecção Hospitalar , Infecções Urinárias , Infecções Relacionadas a Cateter/prevenção & controle , Cateteres de Demora , Infecção Hospitalar/prevenção & controle , Hospitais , Humanos , Cateterismo Urinário/efeitos adversos , Infecções Urinárias/prevenção & controle
12.
J Virol ; 94(11)2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188729

RESUMO

Coronaviruses (CoVs) encode multiple interferon (IFN) antagonists that modulate the host response to virus replication. Here, we evaluated the host transcriptional response to infection with murine coronaviruses encoding independent mutations in one of two different viral antagonists, the deubiquitinase (DUB) within nonstructural protein 3 or the endoribonuclease (EndoU) within nonstructural protein 15. We used transcriptomics approaches to compare the scope and kinetics of the host response to the wild-type (WT), DUBmut, and EndoUmut viruses in infected macrophages. We found that the EndoUmut virus activates a focused response that predominantly involves type I interferons and interferon-related genes, whereas the WT and DUBmut viruses more broadly stimulate upregulation of over 2,800 genes, including networks associated with activating the unfolded protein response (UPR) and the proinflammatory response associated with viral pathogenesis. This study highlights the role of viral interferon antagonists in shaping the kinetics and magnitude of the host response during virus infection and demonstrates that inactivating a dominant viral antagonist, the coronavirus endoribonuclease, dramatically alters the host response in macrophages.IMPORTANCE Macrophages are an important cell type during coronavirus infections because they "notice" the infection and respond by inducing type I interferons, which limits virus replication. In turn, coronaviruses encode proteins that mitigate the cell's ability to signal an interferon response. Here, we evaluated the host macrophage response to two independent mutant coronaviruses, one with reduced deubiquitinating activity (DUBmut) and the other containing an inactivated endoribonuclease (EndoUmut). We observed a rapid, robust, and focused response to the EndoUmut virus, which was characterized by enhanced expression of interferon and interferon-related genes. In contrast, wild-type virus and the DUBmut virus elicited a more limited interferon response and ultimately activated over 2,800 genes, including players in the unfolded protein response and proinflammatory pathways associated with progression of significant disease. This study reveals that EndoU activity substantially contributes to the ability of coronaviruses to evade the host innate response and to replicate in macrophages.


Assuntos
Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/virologia , Coronavirus/fisiologia , Endorribonucleases/metabolismo , Interferons/metabolismo , Macrófagos/metabolismo , Macrófagos/virologia , Proteínas não Estruturais Virais/metabolismo , Replicação Viral , Animais , Biologia Computacional , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Citocinas/metabolismo , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Mediadores da Inflamação/metabolismo , Macrófagos/imunologia , Camundongos , Modelos Biológicos , Mutação , RNA Viral , Resposta a Proteínas não Dobradas
13.
J Virol ; 94(17)2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32554697

RESUMO

Coronaviruses (CoVs) have repeatedly emerged from wildlife hosts and infected humans and livestock animals to cause epidemics with significant morbidity and mortality. CoVs infect various organs, including respiratory and enteric systems, as exemplified by newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The constellation of viral factors that contribute to developing enteric disease remains elusive. Here, we investigated CoV interferon antagonists for their contribution to enteric pathogenesis. Using an infectious clone of an enteric CoV, porcine epidemic diarrhea virus (icPEDV), we generated viruses with inactive versions of interferon antagonist nonstructural protein 1 (nsp1), nsp15, and nsp16 individually or combined into one virus designated icPEDV-mut4. Interferon-responsive PK1 cells were infected with these viruses and produced higher levels of interferon responses than were seen with wild-type icPEDV infection. icPEDV-mut4 elicited robust interferon responses and was severely impaired for replication in PK1 cells. To evaluate viral pathogenesis, piglets were infected with either icPEDV or icPEDV-mut4. While the icPEDV-infected piglets exhibited clinical disease, the icPEDV-mut4-infected piglets showed no clinical symptoms and exhibited normal intestinal pathology at day 2 postinfection. icPEDV-mut4 replicated in the intestinal tract, as revealed by detection of viral RNA in fecal swabs, with sequence analysis documenting genetic stability of the input strain. Importantly, icPEDV-mut4 infection elicited IgG and neutralizing antibody responses to PEDV. These results identify nsp1, nsp15, and nsp16 as virulence factors that contribute to the development of PEDV-induced diarrhea in swine. Inactivation of these CoV interferon antagonists is a rational approach for generating candidate vaccines to prevent disease and spread of enteric CoVs, including SARS-CoV-2.IMPORTANCE Emerging coronaviruses, including SARS-CoV-2 and porcine CoVs, can infect enterocytes, cause diarrhea, and be shed in the feces. New approaches are needed to understand enteric pathogenesis and to develop vaccines and therapeutics to prevent the spread of these viruses. Here, we exploited a reverse genetic system for an enteric CoV, porcine epidemic diarrhea virus (PEDV), and outline an approach of genetically inactivating highly conserved viral factors known to limit the host innate immune response to infection. Our report reveals that generating PEDV with inactive versions of three viral interferon antagonists, nonstructural proteins 1, 15, and 16, results in a highly attenuated virus that does not cause diarrhea in animals and elicits a neutralizing antibody response in virus-infected animals. This strategy may be useful for generating live attenuated vaccine candidates that prevent disease and fecal spread of enteric CoVs, including SARS-CoV-2.


Assuntos
Infecções por Coronavirus/imunologia , Coronavirus/imunologia , Interferons/imunologia , Vírus da Diarreia Epidêmica Suína/imunologia , Vacinas Atenuadas/imunologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Betacoronavirus/imunologia , COVID-19 , Chlorocebus aethiops , Infecções por Coronavirus/prevenção & controle , Diarreia/patologia , Diarreia/virologia , Modelos Animais de Doenças , Endorribonucleases/antagonistas & inibidores , Fezes/virologia , Íleo/patologia , Imunidade Inata , Jejuno/patologia , Pandemias , Pneumonia Viral/imunologia , Vírus da Diarreia Epidêmica Suína/genética , RNA Viral , RNA Polimerase Dependente de RNA , SARS-CoV-2 , Suínos , Doenças dos Suínos/virologia , Células Vero , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/imunologia
14.
J Virol ; 94(11)2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188728

RESUMO

Coronaviruses express a multifunctional papain-like protease, termed papain-like protease 2 (PLP2). PLP2 acts as a protease that cleaves the viral replicase polyprotein and as a deubiquitinating (DUB) enzyme which removes ubiquitin (Ub) moieties from ubiquitin-conjugated proteins. Previous in vitro studies implicated PLP2/DUB activity as a negative regulator of the host interferon (IFN) response, but the role of DUB activity during virus infection was unknown. Here, we used X-ray structure-guided mutagenesis and functional studies to identify amino acid substitutions within the ubiquitin-binding surface of PLP2 that reduced DUB activity without affecting polyprotein processing activity. We engineered a DUB mutation (Asp1772 to Ala) into a murine coronavirus and evaluated the replication and pathogenesis of the DUB mutant virus (DUBmut) in cultured macrophages and in mice. We found that the DUBmut virus replicates similarly to the wild-type (WT) virus in cultured cells, but the DUBmut virus activates an IFN response at earlier times compared to the wild-type virus infection in macrophages, consistent with DUB activity negatively regulating the IFN response. We compared the pathogenesis of the DUBmut virus to that of the wild-type virus and found that the DUBmut-infected mice had a statistically significant reduction (P < 0.05) in viral titer in liver and spleen at day 5 postinfection (d p.i.), although both wild-type and DUBmut virus infections resulted in similar liver pathology. Overall, this study demonstrates that structure-guided mutagenesis aids the identification of critical determinants of the PLP2-ubiquitin complex and that PLP2/DUB activity plays a role as an interferon antagonist in coronavirus pathogenesis.IMPORTANCE Coronaviruses employ a genetic economy by encoding multifunctional proteins that function in viral replication and also modify the host environment to disarm the innate immune response. The coronavirus papain-like protease 2 (PLP2) domain possesses protease activity, which cleaves the viral replicase polyprotein, and also DUB activity (deconjugating ubiquitin/ubiquitin-like molecules from modified substrates) using identical catalytic residues. To separate the DUB activity from the protease activity, we employed a structure-guided mutagenesis approach and identified residues that are important for ubiquitin binding. We found that mutating the ubiquitin-binding residues results in a PLP2 that has reduced DUB activity but retains protease activity. We engineered a recombinant murine coronavirus to express the DUB mutant and showed that the DUB mutant virus activated an earlier type I interferon response in macrophages and exhibited reduced replication in mice. The results of this study demonstrate that PLP2/DUB is an interferon antagonist and a virulence trait of coronaviruses.


Assuntos
Infecções por Coronavirus/virologia , Vírus da Hepatite Murina/fisiologia , Proteínas Virais/genética , Proteínas Virais/metabolismo , Sequência de Aminoácidos , Animais , Interações Hospedeiro-Patógeno , Interferon Tipo I/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/virologia , Camundongos , Modelos Moleculares , Vírus da Hepatite Murina/patogenicidade , Mutagênese , Conformação Proteica , Relação Estrutura-Atividade , Ubiquitinação , Proteínas Virais/química , Virulência , Replicação Viral
15.
Mol Ecol ; 30(10): 2434-2448, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33772907

RESUMO

Understanding the effects of logging and fire on forest soil communities is integral to our knowledge of forest ecology and effective resource management. The resulting changes in soil biota have substantial impacts on forest succession and associated ecosystem processes. We quantified bacterial and fungal abundance, diversity and community composition across a logging and burn severity gradient, approximately one month after fire, in temperate wet eucalypt forests in Tasmania, Australia. Using amplicon sequencing and real-time quantitative PCR of the bacterial 16S rRNA gene and fungal ITS1 region, we demonstrate that (i) burn severity is a strong driver of soil microbial community composition, (ii) logging and high severity burning substantially reduce the biomass and diversity of soil bacteria and fungi, and (iii) the impacts of logging and burning on soil microbial communities are largely restricted to the top 10 cm of soil, with weak impacts on the subsoil. The impacts of disturbance on microbial community composition are greater than the effects of site-to-site edaphic differences. Fire also drives more divergence in community composition than logging alone. Key microbial taxa driving differences in severely burnt soils include bacterial genera implicated in plant-growth promotion and producing antifungal compounds as well as saprotrophic fungi that are also capable of forming ectomycorrhizal associations. Our research suggests that low-moderate severity burns are important for maintaining diversity and biomass in soil microbial communities but having a range of burn severities across a site contributes to the overall diversity of habitat conditions providing for both microbial and plant diversity.


Assuntos
Microbiota , Solo , Austrália , Ecossistema , Florestas , Fungos/genética , Microbiota/genética , RNA Ribossômico 16S/genética , Microbiologia do Solo , Tasmânia
16.
J Pediatr Gastroenterol Nutr ; 73(2): 271-273, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34016883

RESUMO

ABSTRACT: Recently the National Academies of Sciences, Engineering, and Medicine reported a summary of recommendations from high-income countries on what and how to feed infants and children from birth to 2 years of age. The report notes generally consistent recommendations against providing sugar-sweetened beverages (SSB), juice, and beverages that contain nonnutritive sweeteners to infants and children younger than 2 years. When counselling parents and other caregivers, pediatricians should feel empowered to advise against offering these beverages.


Assuntos
Bebidas , Adoçantes não Calóricos , Criança , Dieta , Humanos , Lactente
17.
Health Commun ; 36(14): 1970-1979, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-32835522

RESUMO

Patient satisfaction is important to patient outcomes. Previous attempts to conceptualize satisfaction have often taken an atheoretical approach and focused on doctors' communication skills. Patients are becoming more active health consumers involved in their health care and current definitions of patient satisfaction may not accurately reflect patient expectations about their health consultations. Earlier research found that meeting patients' emotional needs - through empathy and patient-centered communication - is important to patient satisfaction. New research is needed to explore how those needs can be met given the changing trend in patient behaviors and the focus on patient-centredness. This study employed two communication theories - the Willingness to Communicate Model and Communication Accommodation Theory - to consider both patients' communicative decisions, and the intergroup features of the health context that can influence communicative behaviors. Two hundred and fifty-three patients from health clinics in Canada and Australia described what satisfaction meant to them, and identified what aspects of their health consultation were satisfying (or not), and we investigated their perceptions of doctor's emotional expression. Results suggest that patient perceptions of their participation in the consultation predicts their perceptions of doctor emotional expression, and their satisfaction with the consultation. Patients want both emotional and medical needs met in an environment that balances interpersonal and intergroup communication. Our findings suggest the need to expand current definitions of patient satisfaction, patient-centredness and emotional expression. We discuss the implications of these findings for health practitioners and consider future research that addresses the need for more individualized health care.


Assuntos
Satisfação Pessoal , Relações Médico-Paciente , Comunicação , Humanos , Participação do Paciente , Satisfação do Paciente , Percepção
18.
Alzheimers Dement ; 17(12): 1976-1987, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33984181

RESUMO

INTRODUCTION: Biomarkers that reflect pathologic processes affecting neuronal function during preclinical and early stages of Alzheimer's disease (AD) are needed to aid drug development. METHODS: A targeted, stable isotope, quantitative mass spectrometry-based investigation of longitudinal changes in concentrations of previously identified candidate biomarkers was performed in cerebrospinal fluid (CSF) of Alzheimer's Disease Neuroimaging Initiative participants who were classified as cognitively normal (CN; n = 76) or with mild cognitive impairment (MCI; n = 111) at baseline. RESULTS: Of the candidate biomarkers, the CSF concentration of neuronal pentraxin 2 (NPTX2), a protein involved in synaptic function, exhibited rates of change that were significantly different between three comparison groups (i.e., CN vs. MCI participants; AD pathology positive vs. negative defined by phosphorylated tau181/amyloid beta1-42 ratio; and clinical progressors vs. non-progressors). The rate of change of NPTX2 also significantly correlated with declining cognition. DISCUSSION: CSF NPTX2 concentration is a strong prognostic biomarker candidate of accelerated cognitive decline with potential use as a therapeutic target.


Assuntos
Doença de Alzheimer , Biomarcadores/líquido cefalorraquidiano , Proteína C-Reativa/líquido cefalorraquidiano , Disfunção Cognitiva , Proteínas do Tecido Nervoso/líquido cefalorraquidiano , Proteômica , Idoso , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/patologia , Humanos , Estudos Longitudinais , Espectrometria de Massas , Fosforilação , Proteínas tau/líquido cefalorraquidiano
19.
J Infect Dis ; 222(1): 158-168, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32052021

RESUMO

BACKGROUND: Kawasaki disease (KD) is the leading cause of childhood acquired heart disease in developed nations and can result in coronary artery aneurysms and death. Clinical and epidemiologic features implicate an infectious cause but specific antigenic targets of the disease are unknown. Peripheral blood plasmablasts are normally highly clonally diverse but the antibodies they encode are approximately 70% antigen-specific 1-2 weeks after infection. METHODS: We isolated single peripheral blood plasmablasts from children with KD 1-3 weeks after onset and prepared 60 monoclonal antibodies (mAbs). We used the mAbs to identify their target antigens and assessed serologic response among KD patients and controls to specific antigen. RESULTS: Thirty-two mAbs from 9 of 11 patients recognize antigen within intracytoplasmic inclusion bodies in ciliated bronchial epithelial cells of fatal cases. Five of these mAbs, from 3 patients with coronary aneurysms, recognize a specific peptide, which blocks binding to inclusion bodies. Sera from 5/8 KD patients day ≥ 8 after illness onset, compared with 0/17 infant controls (P < .01), recognized the KD peptide antigen. CONCLUSIONS: These results identify a protein epitope targeted by the antibody response to KD and provide a means to elucidate the pathogenesis of this important worldwide pediatric problem.


Assuntos
Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Formação de Anticorpos/genética , Células Sanguíneas/imunologia , Epitopos/imunologia , Síndrome de Linfonodos Mucocutâneos/genética , Síndrome de Linfonodos Mucocutâneos/imunologia , Feminino , Humanos , Lactente , Masculino , Síndrome de Linfonodos Mucocutâneos/epidemiologia , Estados Unidos/epidemiologia
20.
Lancet ; 393(10182): 1708-1720, 2019 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-30935734

RESUMO

BACKGROUND: Lack of evidence-based outcomes data leads to uncertainty in developing treatment regimens in children who are newly diagnosed with ulcerative colitis. We hypothesised that pretreatment clinical, transcriptomic, and microbial factors predict disease course. METHODS: In this inception cohort study, we recruited paediatric patients aged 4-17 years with newly diagnosed ulcerative colitis from 29 centres in the USA and Canada. Patients initially received standardised mesalazine or corticosteroids, with pre-established criteria for escalation to immunomodulators (ie, thiopurines) or anti-tumor necrosis factor-α (TNFα) therapy. We used RNA sequencing to define rectal gene expression before treatment, and 16S sequencing to characterise rectal and faecal microbiota. The primary outcome was week 52 corticosteroid-free remission with no therapy beyond mesalazine. We assessed factors associated with the primary outcome using logistic regression models of the per-protocol population. This study is registered with ClinicalTrials.gov, number NCT01536535. FINDINGS: Between July 10, 2012, and April 21, 2015, of 467 patients recruited, 428 started medical therapy, of whom 400 (93%) were evaluable at 52 weeks and 386 (90%) completed the study period with no protocol violations. 150 (38%) of 400 participants achieved week 52 corticosteroid-free remission, of whom 147 (98%) were taking mesalazine and three (2%) were taking no medication. 74 (19%) of 400 were escalated to immunomodulators alone, 123 (31%) anti-TNFα therapy, and 25 (6%) colectomy. Low baseline clinical severity, high baseline haemoglobin, and week 4 clinical remission were associated with achieving week 52 corticosteroid-free remission (n=386, logistic model area under the curve [AUC] 0·70, 95% CI 0·65-0·75; specificity 77%, 95% CI 71-82). Baseline severity and remission by week 4 were validated in an independent cohort of 274 paediatric patients with newly diagnosed ulcerative colitis. After adjusting for clinical predictors, an antimicrobial peptide gene signature (odds ratio [OR] 0·57, 95% CI 0·39-0·81; p=0·002) and abundance of Ruminococcaceae (OR 1·43, 1·02-2·00; p=0·04), and Sutterella (OR 0·81, 0·65-1·00; p=0·05) were independently associated with week 52 corticosteroid-free remission. INTERPRETATION: Our findings support the utility of initial clinical activity and treatment response by 4 weeks to predict week 52 corticosteroid-free remission with mesalazine alone in children who are newly diagnosed with ulcerative colitis. The development of personalised clinical and biological signatures holds the promise of informing ulcerative colitis therapeutic decisions. FUNDING: US National Institutes of Health.


Assuntos
Corticosteroides/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Mesalamina/uso terapêutico , Adolescente , Biomarcadores/metabolismo , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Resultado do Tratamento
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