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1.
Nature ; 605(7911): 741-746, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35508656

RESUMO

Phosphoinositide 3-kinase δ (PI3Kδ) has a key role in lymphocytes, and inhibitors that target this PI3K have been approved for treatment of B cell malignancies1-3. Although studies in mouse models of solid tumours have demonstrated that PI3Kδ inhibitors (PI3Kδi) can induce anti-tumour immunity4,5, its effect on solid tumours in humans remains unclear. Here we assessed the effects of the PI3Kδi AMG319 in human patients with head and neck cancer in a neoadjuvant, double-blind, placebo-controlled randomized phase II trial (EudraCT no. 2014-004388-20). PI3Kδ inhibition decreased the number of tumour-infiltrating regulatory T (Treg) cells and enhanced the cytotoxic potential of tumour-infiltrating T cells. At the tested doses of AMG319, immune-related adverse events (irAEs) required treatment to be discontinued in 12 out of 21 of patients treated with AMG319, suggestive of systemic effects on Treg cells. Accordingly, in mouse models, PI3Kδi decreased the number of Treg cells systemically and caused colitis. Single-cell RNA-sequencing analysis revealed a PI3Kδi-driven loss of tissue-resident colonic ST2 Treg cells, accompanied by expansion of pathogenic T helper 17 (TH17) and type 17 CD8+ T (TC17) cells, which probably contributed to toxicity; this points towards a specific mode of action for the emergence of irAEs. A modified treatment regimen with intermittent dosing of PI3Kδi in mouse models led to a significant decrease in tumour growth without inducing pathogenic T cells in colonic tissue, indicating that alternative dosing regimens might limit toxicity.


Assuntos
Antineoplásicos , Neoplasias de Cabeça e Pescoço , Adenosina/uso terapêutico , Animais , Antineoplásicos/uso terapêutico , Modelos Animais de Doenças , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Imunoterapia , Camundongos , Fosfatidilinositol 3-Quinases , Quinolinas/uso terapêutico , Linfócitos T Reguladores
2.
Nature ; 600(7888): 295-301, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34695836

RESUMO

SARS-CoV-2 is a single-stranded RNA virus that causes COVID-19. Given its acute and often self-limiting course, it is likely that components of the innate immune system play a central part in controlling virus replication and determining clinical outcome. Natural killer (NK) cells are innate lymphocytes with notable activity against a broad range of viruses, including RNA viruses1,2. NK cell function may be altered during COVID-19 despite increased representation of NK cells with an activated and adaptive phenotype3,4. Here we show that a decline in viral load in COVID-19 correlates with NK cell status and that NK cells can control SARS-CoV-2 replication by recognizing infected target cells. In severe COVID-19, NK cells show defects in virus control, cytokine production and cell-mediated cytotoxicity despite high expression of cytotoxic effector molecules. Single-cell RNA sequencing of NK cells over the time course of the COVID-19 disease spectrum reveals a distinct gene expression signature. Transcriptional networks of interferon-driven NK cell activation are superimposed by a dominant transforming growth factor-ß (TGFß) response signature, with reduced expression of genes related to cell-cell adhesion, granule exocytosis and cell-mediated cytotoxicity. In severe COVID-19, serum levels of TGFß peak during the first two weeks of infection, and serum obtained from these patients severely inhibits NK cell function in a TGFß-dependent manner. Our data reveal that an untimely production of TGFß is a hallmark of severe COVID-19 and may inhibit NK cell function and early control of the virus.


Assuntos
COVID-19/imunologia , Células Matadoras Naturais/imunologia , SARS-CoV-2/imunologia , Fator de Crescimento Transformador beta/imunologia , Atlas como Assunto , Regulação da Expressão Gênica/imunologia , Humanos , Imunidade Inata , Influenza Humana/imunologia , Células Matadoras Naturais/patologia , RNA-Seq , Análise de Célula Única , Fatores de Tempo , Fator de Crescimento Transformador beta/sangue , Carga Viral/imunologia , Replicação Viral/imunologia
3.
Nature ; 581(7809): 465-469, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32235945

RESUMO

Coronavirus disease 2019 (COVID-19) is an acute infection of the respiratory tract that emerged in late 20191,2. Initial outbreaks in China involved 13.8% of cases with severe courses, and 6.1% of cases with critical courses3. This severe presentation may result from the virus using a virus receptor that is expressed predominantly in the lung2,4; the same receptor tropism is thought to have determined the pathogenicity-but also aided in the control-of severe acute respiratory syndrome (SARS) in 20035. However, there are reports of cases of COVID-19 in which the patient shows mild upper respiratory tract symptoms, which suggests the potential for pre- or oligosymptomatic transmission6-8. There is an urgent need for information on virus replication, immunity and infectivity in specific sites of the body. Here we report a detailed virological analysis of nine cases of COVID-19 that provides proof of active virus replication in tissues of the upper respiratory tract. Pharyngeal virus shedding was very high during the first week of symptoms, with a peak at 7.11 × 108 RNA copies per throat swab on day 4. Infectious virus was readily isolated from samples derived from the throat or lung, but not from stool samples-in spite of high concentrations of virus RNA. Blood and urine samples never yielded virus. Active replication in the throat was confirmed by the presence of viral replicative RNA intermediates in the throat samples. We consistently detected sequence-distinct virus populations in throat and lung samples from one patient, proving independent replication. The shedding of viral RNA from sputum outlasted the end of symptoms. Seroconversion occurred after 7 days in 50% of patients (and by day 14 in all patients), but was not followed by a rapid decline in viral load. COVID-19 can present as a mild illness of the upper respiratory tract. The confirmation of active virus replication in the upper respiratory tract has implications for the containment of COVID-19.


Assuntos
Betacoronavirus/imunologia , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Hospitalização , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Soroconversão , Replicação Viral , Anticorpos Antivirais/análise , Anticorpos Antivirais/imunologia , Sequência de Bases , Betacoronavirus/genética , Betacoronavirus/patogenicidade , Sangue/virologia , COVID-19 , Teste para COVID-19 , Técnicas de Laboratório Clínico , Proteínas do Envelope de Coronavírus , Infecções por Coronavirus/diagnóstico , Fezes/química , Fezes/virologia , Humanos , Imunoglobulina G/análise , Imunoglobulina G/imunologia , Imunoglobulina M/análise , Imunoglobulina M/imunologia , Pulmão/virologia , Pandemias , Faringe/virologia , Pneumonia Viral/diagnóstico , Polimorfismo de Nucleotídeo Único/genética , RNA Viral/análise , SARS-CoV-2 , Escarro/virologia , Urina/virologia , Proteínas do Envelope Viral/genética , Carga Viral/imunologia , Eliminação de Partículas Virais
4.
PLoS Pathog ; 19(9): e1011657, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37747932

RESUMO

Inhibitors of bromodomain and extra-terminal proteins (iBETs), including JQ-1, have been suggested as potential prophylactics against SARS-CoV-2 infection. However, molecular mechanisms underlying JQ-1-mediated antiviral activity and its susceptibility to viral subversion remain incompletely understood. Pretreatment of cells with iBETs inhibited infection by SARS-CoV-2 variants and SARS-CoV, but not MERS-CoV. The antiviral activity manifested itself by reduced reporter expression of recombinant viruses, and reduced viral RNA quantities and infectious titers in the culture supernatant. While we confirmed JQ-1-mediated downregulation of expression of angiotensin-converting enzyme 2 (ACE2) and interferon-stimulated genes (ISGs), multi-omics analysis addressing the chromatin accessibility, transcriptome and proteome uncovered induction of an antiviral nuclear factor erythroid 2-related factor 2 (NRF-2)-mediated cytoprotective response as an additional mechanism through which JQ-1 inhibits SARS-CoV-2 replication. Pharmacological inhibition of NRF-2, and knockdown of NRF-2 and its target genes reduced JQ-1-mediated inhibition of SARS-CoV-2 replication. Serial passaging of SARS-CoV-2 in the presence of JQ-1 resulted in predominance of ORF6-deficient variant, which exhibited resistance to JQ-1 and increased sensitivity to exogenously administered type I interferon (IFN-I), suggesting a minimised need for SARS-CoV-2 ORF6-mediated repression of IFN signalling in the presence of JQ-1. Importantly, JQ-1 exhibited a transient antiviral activity when administered prophylactically in human airway bronchial epithelial cells (hBAECs), which was gradually subverted by SARS-CoV-2, and no antiviral activity when administered therapeutically following an established infection. We propose that JQ-1 exerts pleiotropic effects that collectively induce an antiviral state in the host, which is ultimately nullified by SARS-CoV-2 infection, raising questions about the clinical suitability of the iBETs in the context of COVID-19.


Assuntos
COVID-19 , Interferon Tipo I , Humanos , SARS-CoV-2/metabolismo , Interferon Tipo I/farmacologia , Proteínas Virais/metabolismo , Antivirais/farmacologia
5.
PLoS Biol ; 20(11): e3001871, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36383605

RESUMO

Epidemiological data demonstrate that Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) Alpha and Delta are more transmissible, infectious, and pathogenic than previous variants. Phenotypic properties of VOC remain understudied. Here, we provide an extensive functional study of VOC Alpha replication and cell entry phenotypes assisted by reverse genetics, mutational mapping of spike in lentiviral pseudotypes, viral and cellular gene expression studies, and infectivity stability assays in an enhanced range of cell and epithelial culture models. In almost all models, VOC Alpha spread less or equally efficiently as ancestral (B.1) SARS-CoV-2. B.1. and VOC Alpha shared similar susceptibility to serum neutralization. Despite increased relative abundance of specific sgRNAs in the context of VOC Alpha infection, immune gene expression in infected cells did not differ between VOC Alpha and B.1. However, inferior spreading and entry efficiencies of VOC Alpha corresponded to lower abundance of proteolytically cleaved spike products presumably linked to the T716I mutation. In addition, we identified a bronchial cell line, NCI-H1299, which supported 24-fold increased growth of VOC Alpha and is to our knowledge the only cell line to recapitulate the fitness advantage of VOC Alpha compared to B.1. Interestingly, also VOC Delta showed a strong (595-fold) fitness advantage over B.1 in these cells. Comparative analysis of chimeric viruses expressing VOC Alpha spike in the backbone of B.1, and vice versa, showed that the specific replication phenotype of VOC Alpha in NCI-H1299 cells is largely determined by its spike protein. Despite undetectable ACE2 protein expression in NCI-H1299 cells, CRISPR/Cas9 knock-out and antibody-mediated blocking experiments revealed that multicycle spread of B.1 and VOC Alpha required ACE2 expression. Interestingly, entry of VOC Alpha, as opposed to B.1 virions, was largely unaffected by treatment with exogenous trypsin or saliva prior to infection, suggesting enhanced resistance of VOC Alpha spike to premature proteolytic cleavage in the extracellular environment of the human respiratory tract. This property may result in delayed degradation of VOC Alpha particle infectivity in conditions typical of mucosal fluids of the upper respiratory tract that may be recapitulated in NCI-H1299 cells closer than in highly ACE2-expressing cell lines and models. Our study highlights the importance of cell model evaluation and comparison for in-depth characterization of virus variant-specific phenotypes and uncovers a fine-tuned interrelationship between VOC Alpha- and host cell-specific determinants that may underlie the increased and prolonged virus shedding detected in patients infected with VOC Alpha.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Enzima de Conversão de Angiotensina 2/genética , Eliminação de Partículas Virais , Anticorpos Bloqueadores
7.
Nature ; 557(7705): 418-423, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29743673

RESUMO

Hepatitis B virus (HBV) is a major cause of human hepatitis. There is considerable uncertainty about the timescale of its evolution and its association with humans. Here we present 12 full or partial ancient HBV genomes that are between approximately 0.8 and 4.5 thousand years old. The ancient sequences group either within or in a sister relationship with extant human or other ape HBV clades. Generally, the genome properties follow those of modern HBV. The root of the HBV tree is projected to between 8.6 and 20.9 thousand years ago, and we estimate a substitution rate of 8.04 × 10-6-1.51 × 10-5 nucleotide substitutions per site per year. In several cases, the geographical locations of the ancient genotypes do not match present-day distributions. Genotypes that today are typical of Africa and Asia, and a subgenotype from India, are shown to have an early Eurasian presence. The geographical and temporal patterns that we observe in ancient and modern HBV genotypes are compatible with well-documented human migrations during the Bronze and Iron Ages1,2. We provide evidence for the creation of HBV genotype A via recombination, and for a long-term association of modern HBV genotypes with humans, including the discovery of a human genotype that is now extinct. These data expose a complexity of HBV evolution that is not evident when considering modern sequences alone.


Assuntos
Evolução Molecular , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Hepatite B/virologia , Filogenia , África , Animais , Ásia , Europa (Continente) , Genótipo , Vírus da Hepatite B/classificação , História Antiga , História Medieval , Hominidae/virologia , Migração Humana/história , Humanos , Recombinação Genética
8.
Proc Natl Acad Sci U S A ; 118(28)2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34260380

RESUMO

Catastrophic decline of Indigenous populations in the Americas following European contact is one of the most severe demographic events in the history of humanity, but uncertainty persists about the timing and scale of the collapse, which has implications for not only Indigenous history but also the understanding of historical ecology. A long-standing hypothesis that a continent-wide pandemic broke out immediately upon the arrival of Spanish seafarers has been challenged in recent years by a model of regional epidemics erupting asynchronously, causing different rates of population decline in different areas. Some researchers have suggested that, in California, significant depopulation occurred during the first two centuries of the post-Columbus era, which led to a "rebound" in native flora and fauna by the time of sustained European contact after 1769. Here, we combine a comprehensive prehistoric osteological dataset (n = 10,256 individuals) with historic mission mortuary records (n = 23,459 individuals) that together span from 3050 cal BC to AD 1870 to systematically evaluate changes in mortality over time by constructing life tables and conducting survival analysis of age-at-death records. Results show that a dramatic shift in the shape of mortality risk consistent with a plague-like population structure began only after sustained contact with European invaders, when permanent Spanish settlements and missions were established ca. AD 1770. These declines reflect the syndemic effects of newly introduced diseases and the severe cultural disruption of Indigenous lifeways by the Spanish colonial system.


Assuntos
Epidemias/história , Grupos Populacionais , Fatores Etários , Arqueologia , California , História do Século XVIII , História do Século XIX , Humanos , Estimativa de Kaplan-Meier
9.
Euro Surveill ; 29(2)2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38214083

RESUMO

Variant BA.2.86 and its descendant, JN.1, of SARS-CoV-2 are rising in incidence across Europe and globally. We isolated recent JN.1, BA.2.86, EG.5, XBB.1.5 and earlier variants. We tested live virus neutralisation of sera taken in September 2023 from vaccinated and exposed healthy persons (n = 39). We found clear neutralisation escape against recent variants but no specific pronounced escape for BA.2.86 or JN.1. Neutralisation escape corresponds to recent variant predominance but may not be causative of the recent upsurge in JN.1 incidence.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Europa (Continente)/epidemiologia , Nível de Saúde , Anticorpos Antivirais , Anticorpos Neutralizantes
10.
J Nurs Adm ; 54(2): 102-110, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38261641

RESUMO

OBJECTIVE: This study examined how frontline nurse managers (FLNMs) perceive and experience formal and informal social support and how personal factors and social support relate to their transformational leadership (TL) behaviors. BACKGROUND: Ineffective leadership by FLNMs is associated with costly outcomes. Evidence suggests that leadership development is a function of personal and social factors; however, a better understanding of this process is needed. METHODS: A convergent mixed-methods design was used. The quantitative strand included a cross-sectional survey in a sample of FLNMs. The qualitative strand used a semistructured interview and a descriptive qualitative approach with a subset of this sample. RESULTS: Formal and informal social support is positively related to the TL behaviors of FLNMs as evidenced by the convergent data. The influence of family members in the work-related decisions of FLNMs has been underreported in the literature and is an area for consideration in supporting retention and desired leadership behaviors. CONCLUSION: The findings of this study imply a need for organizations to establish systems that endorse the growth of FLNMS, create opportunities for career advancement, and integrate members of the FLNMs' personal support systems into recognition initiatives.


Assuntos
Acidose Láctica , Enfermeiros Administradores , Humanos , Estudos Transversais , Liderança , Apoio Social
11.
Comput Inform Nurs ; 42(2): 94-103, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38062552

RESUMO

The aim of this study was to describe medication administration and alert patterns among a cohort of new graduate nurses over the first year of practice. Medical errors related to clinical decision-making, including medication administration errors, may occur more frequently among new graduate nurses. To better understand nursing workflow and documentation workload in today's clinical environment, it is important to understand patterns of medication administration and alert generation during barcode-assisted medication administration. Study objectives were addressed through a descriptive, longitudinal, observational cohort design using secondary data analysis. Set in a large, urban medical center in the United States, the study sample included 132 new graduate nurses who worked on adult, inpatient units and administered medication using barcode-assisted medication administration. Data were collected through electronic health record and administration sources. New graduate nurses in the sample experienced a total of 587 879 alert and medication administration encounters, administering 772 unique medications to 17 388 unique patients. Nurses experienced an average medication workload of 28.09 medications per shift, 3.98% of which were associated with alerts, over their first year of practice. In addition to high volume of medication administration, new graduate nurses administer many different types of medications and are exposed to numerous alerts while using barcode-assisted medication administration.


Assuntos
Educação de Pós-Graduação em Enfermagem , Erros de Medicação , Adulto , Humanos , Documentação , Registros Eletrônicos de Saúde , Erros de Medicação/prevenção & controle , Preparações Farmacêuticas , Estudos Longitudinais , Estudos de Coortes
12.
Comput Inform Nurs ; 42(3): 199-206, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38206171

RESUMO

Paramount to patient safety is the ability for nurses to make clinical decisions free from human error. Yet, the dynamic clinical environment in which nurses work is characterized by uncertainty, urgency, and high consequence, necessitating that nurses make quick and critical decisions. The aim of this study was to examine the influence of human and environmental factors on the decision to administer among new graduate nurses in response to alert generation during bar code-assisted medication administration. The design for this study was a descriptive, longitudinal, observational cohort design using EHR audit log and administrative data. The study was set at a large, urban medical center in the United States and included 132 new graduate nurses who worked on adult, inpatient units. Research variables included human and environmental factors. Data analysis included descriptive and inferential analyses. This study found that participants continued with administration of a medication in 90.75% of alert encounters. When considering the response to an alert, residency cohort, alert category, and previous exposure variables were associated with the decision to proceed with administration. It is important to continue to study factors that influence nurses' decision-making, particularly during the process of medication administration, to improve patient safety and outcomes.


Assuntos
Educação de Pós-Graduação em Enfermagem , Adulto , Humanos , Análise de Dados , Hospitais , Pacientes Internados , Segurança do Paciente
13.
Am J Physiol Endocrinol Metab ; 325(3): E207-E213, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37467021

RESUMO

Individuals with insulin resistance and obesity display higher skeletal muscle production of nonoxidized glycolytic products (i.e., lactate), and lower complete mitochondrial substrate oxidation to CO2. These findings have also been observed in individuals without obesity and are associated with an increased risk for metabolic disease. The purpose of this study was to determine if substrate preference is evident at the earliest stage of life (birth) and to provide a clinical blood marker (lactate) that could be indicative of a predisposition for metabolic disease later. We used radiolabeled tracers to assess substrate oxidation and insulin sensitivity of myogenically differentiated mesenchymal stem cells (MSCs), a proxy of infant skeletal muscle tissue, derived from umbilical cords of full-term infants. We found that greater production of nonoxidized glycolytic products (lactate, pyruvate, alanine) is directly proportional to lower substrate oxidation and insulin sensitivity in MSCs. In addition, we found an inverse relationship between the ratio of complete glucose oxidation to CO2 and infant blood lactate at 1 mo of age. Collectively, considering that higher lactate was associated with lower MSC glucose oxidation and has been shown to be implicated with metabolic disease, it may be an early indicator of infant skeletal muscle phenotype.NEW & NOTEWORTHY In infant myogenically differentiated mesenchymal stem cells, greater production of nonoxidized glycolytic products was directly proportional to lower substrate oxidation and insulin resistance. Glucose oxidation was inversely correlated with infant blood lactate. This suggests that innate differences in infant substrate oxidation exist at birth and could be associated with the development of metabolic disease later in life. Clinical assessment of infant blood lactate could be used as an early indicator of skeletal muscle phenotype.


Assuntos
Resistência à Insulina , Células-Tronco Mesenquimais , Humanos , Dióxido de Carbono , Glicólise/fisiologia , Glucose/metabolismo , Músculo Esquelético/metabolismo , Obesidade/metabolismo , Ácido Láctico/metabolismo , Ácido Pirúvico/metabolismo , Células-Tronco Mesenquimais/metabolismo , Insulina/metabolismo
14.
Emerg Infect Dis ; 29(12): 2524-2527, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37796297

RESUMO

Hepatitis A virus (HAV) is a common human pathogen found exclusively in primates. In a molecular and serologic study of 64 alpacas in Bolivia, we detected RNA of distinct HAV in ≈9% of animals and HAV antibodies in ≈64%. Complete-genome analysis suggests a long association of HAV with alpacas.


Assuntos
Camelídeos Americanos , Vírus da Hepatite A , Animais , Humanos , Vírus da Hepatite A/genética , Bolívia/epidemiologia , Genótipo , RNA
15.
Emerg Infect Dis ; 29(5)2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37054986

RESUMO

Since late 2020, SARS-CoV-2 variants have regularly emerged with competitive and phenotypic differences from previously circulating strains, sometimes with the potential to escape from immunity produced by prior exposure and infection. The Early Detection group is one of the constituent groups of the US National Institutes of Health National Institute of Allergy and Infectious Diseases SARS-CoV-2 Assessment of Viral Evolution program. The group uses bioinformatic methods to monitor the emergence, spread, and potential phenotypic properties of emerging and circulating strains to identify the most relevant variants for experimental groups within the program to phenotypically characterize. Since April 2021, the group has prioritized variants monthly. Prioritization successes include rapidly identifying most major variants of SARS-CoV-2 and providing experimental groups within the National Institutes of Health program easy access to regularly updated information on the recent evolution and epidemiology of SARS-CoV-2 that can be used to guide phenotypic investigations.


Assuntos
COVID-19 , SARS-CoV-2 , Estados Unidos/epidemiologia , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , National Institutes of Health (U.S.)
16.
Virol J ; 20(1): 257, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37940989

RESUMO

BACKGROUND: Intrinsic fitness costs are likely to have guided the selection of lineage-determining mutations during emergence of variants of SARS-CoV-2. Whereas changes in receptor affinity and antibody neutralization have been thoroughly mapped for individual mutations in spike, their influence on intrinsic replicative fitness remains understudied. METHODS: We analyzed mutations in immunodominant spike epitope E484 that became temporarily fixed over the pandemic. We engineered the resulting immune escape mutations E484K, -A, and -Q in recombinant SARS-CoV-2. We characterized viral replication, entry, and competitive fitness with and without immune serum from humans with defined exposure/vaccination history and hamsters monospecifically infected with the E484K variant. We additionally engineered a virus containing the Omicron signature mutations N501Y and Q498R that were predicted to epistatically enhance receptor binding. RESULTS: Multistep growth kinetics in Vero-, Calu-3, and NCI-H1299 were identical between viruses. Synchronized entry experiments based on cold absorption and temperature shift identified only an insignificant trend toward faster entry of the E484K variant. Competitive passage experiments revealed clear replicative fitness differences. In absence of immune serum, E484A and E484Q, but not E484K, were replaced by wildtype (WT) in competition assays. In presence of immune serum, all three mutants outcompeted WT. Decreased E484A fitness levels were over-compensated for by N501Y and Q498R, identifying a putative Omicron founder background that exceeds the intrinsic and effective fitness of WT and matches that of E484K. Critically, the E484A/Q498R/N501Y mutant and E484K have equal fitness also in presence of pre-Omicron vaccinee serum, whereas the fitness gain by E484K is lost in the presence of serum raised against the E484K variant in hamsters. CONCLUSIONS: The emergence of E484A and E484Q prior to widespread population immunity may have been limited by fitness costs. In populations already exposed to the early immune escape epitope E484K, the Omicron founder background may have provided a basis for alternative immune escape evolution via E484A. Studies of major antigenic epitope changes with and without their epistatic context help reconstruct the sequential adjustments of intrinsic fitness versus neutralization escape during the evolution of major SARS-CoV-2 variants in an increasingly immune human population.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Cricetinae , Humanos , Epitopos/genética , SARS-CoV-2/genética , Mutação , Soros Imunes , Epitopos Imunodominantes , Glicoproteína da Espícula de Coronavírus/genética , Anticorpos Neutralizantes
17.
J Drugs Dermatol ; 22(2): 139-147, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36745371

RESUMO

BACKGROUND: Patients with atopic dermatitis (AD) need safe and effective topical treatments. OBJECTIVE: To assess safety and efficacy of roflumilast cream in patients with mild to moderate AD. METHODS: In this phase 2, proof of concept trial, patients (N=136) aged ≥12 years with AD were randomized to once-daily roflumilast cream 0.15%, roflumilast cream 0.05%, or vehicle cream for 4 weeks. Absolute change from baseline in Eczema Area and Severity Index (EASI) score at week 4 (primary endpoint), percentage change and responder rates, Validated Investigator Global Assessment-AD (vIGA-AD), and safety were assessed. RESULTS: At week 4, mean absolute changes in EASI were −6.4 (P=0.097 vs vehicle), −6.0 (P=0.356), and −4.8 with roflumilast 0.15%, roflumilast 0.05%, and vehicle, respectively. Significant improvements were observed for percentage change from baseline in EASI, patients reaching 75% improvement in EASI, and patients achieving vIGA-AD score of “clear” or “almost clear.” Treatment-related adverse events (AEs) occurred in 2 (2.2%) patients receiving roflumilast (mild rash and moderate application site pain). Only 1 (1.1%) patient receiving roflumilast discontinued study/drug due to an AE. LIMITATIONS: Small number of patients. CONCLUSIONS: Results support additional larger clinical trials of roflumilast cream to assess its potential as a once-daily, nonsteroidal topical AD treatment. CLINICALTRIALS: gov identifier NCT03916081 J Drugs Dermatol. 2023;22(2):139-147. doi:10.36849/JDD.7295.


Assuntos
Dermatite Atópica , Humanos , Aminopiridinas/efeitos adversos , Benzamidas/efeitos adversos , Dermatite Atópica/diagnóstico , Dermatite Atópica/tratamento farmacológico , Método Duplo-Cego , Emolientes/uso terapêutico , Estudo de Prova de Conceito , Índice de Gravidade de Doença , Resultado do Tratamento
18.
Proc Natl Acad Sci U S A ; 117(30): 17977-17983, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32651267

RESUMO

Hepatitis delta virus (HDV) is a human hepatitis-causing RNA virus, unrelated to any other taxonomic group of RNA viruses. Its occurrence as a satellite virus of hepatitis B virus (HBV) is a singular case in animal virology for which no consensus evolutionary explanation exists. Here we present a mammalian deltavirus that does not occur in humans, identified in the neotropical rodent species Proechimys semispinosus The rodent deltavirus is highly distinct, showing a common ancestor with a recently described deltavirus in snakes. Reverse genetics based on a tandem minus-strand complementary DNA genome copy under the control of a cytomegalovirus (CMV) promoter confirms autonomous genome replication in transfected cells, with initiation of replication from the upstream genome copy. In contrast to HDV, a large delta antigen is not expressed and the farnesylation motif critical for HBV interaction is absent from a genome region that might correspond to a hypothetical rodent large delta antigen. Correspondingly, there is no evidence for coinfection with an HBV-related hepadnavirus based on virus detection and serology in any deltavirus-positive animal. No other coinfecting viruses were detected by RNA sequencing studies of 120 wild-caught animals that could serve as a potential helper virus. The presence of virus in blood and pronounced detection in reproductively active males suggest horizontal transmission linked to competitive behavior. Our study establishes a nonhuman, mammalian deltavirus that occurs as a horizontally transmitted infection, is potentially cleared by immune response, is not focused in the liver, and possibly does not require helper virus coinfection.


Assuntos
Coinfecção , Infecções por Hepadnaviridae/veterinária , Hepadnaviridae/fisiologia , Hepatite D/veterinária , Vírus Delta da Hepatite/fisiologia , Doenças dos Roedores/virologia , Roedores/virologia , Animais , Linhagem Celular Tumoral , Genoma Viral , Genômica/métodos , Hepadnaviridae/classificação , Vírus Delta da Hepatite/classificação , Humanos , Filogenia
19.
Nurs Outlook ; 71(3): 101958, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36963372

RESUMO

Advances in technologies including omics, apps, imaging, sensors, and big data are increasingly being integrated into research by nurse scientists, but the impact on improving health equity is still unclear. In this article, nursing research faculty from one institution discuss challenges and opportunities experienced when integrating various technologies into their research aimed at promoting health equity. Using exemplars from faculty experiences, a three-pronged approach to keeping patients and communities and the goal of health equity central in research while incorporating advancing technologies is described. This approach includes establishing long-term engagement with populations underrepresented in research, adopting strategies to increase diversity in study participant recruitment, and training and collaboration among a diverse workforce of educators, clinicians, and researchers. Training nurse scientists in integrating data and technology for advancing the science on health equity will shift the culture of how we understand, collaborate, and grow with the communities in which we train and practice as nurse scientists.


Assuntos
Equidade em Saúde , Pesquisa em Enfermagem , Humanos , Promoção da Saúde , Pesquisa em Enfermagem/métodos , Docentes de Enfermagem , Recursos Humanos
20.
J Clin Immunol ; 42(6): 1111-1129, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35511314

RESUMO

PURPOSE: Six to 19% of critically ill COVID-19 patients display circulating auto-antibodies against type I interferons (IFN-AABs). Here, we establish a clinically applicable strategy for early identification of IFN-AAB-positive patients for potential subsequent clinical interventions. METHODS: We analyzed sera of 430 COVID-19 patients from four hospitals for presence of IFN-AABs by ELISA. Binding specificity and neutralizing activity were evaluated via competition assay and virus-infection-based neutralization assay. We defined clinical parameters associated with IFN-AAB positivity. In a subgroup of critically ill patients, we analyzed effects of therapeutic plasma exchange (TPE) on the levels of IFN-AABs, SARS-CoV-2 antibodies and clinical outcome. RESULTS: The prevalence of neutralizing AABs to IFN-α and IFN-ω in COVID-19 patients from all cohorts was 4.2% (18/430), while being undetectable in an uninfected control cohort. Neutralizing IFN-AABs were detectable exclusively in critically affected (max. WHO score 6-8), predominantly male (83%) patients (7.6%, 18/237 for IFN-α-AABs and 4.6%, 11/237 for IFN-ω-AABs in 237 patients with critical COVID-19). IFN-AABs were present early post-symptom onset and at the peak of disease. Fever and oxygen requirement at hospital admission co-presented with neutralizing IFN-AAB positivity. IFN-AABs were associated with lower probability of survival (7.7% versus 80.9% in patients without IFN-AABs). TPE reduced levels of IFN-AABs in three of five patients and may increase survival of IFN-AAB-positive patients compared to those not undergoing TPE. CONCLUSION: IFN-AABs may serve as early biomarker for the development of severe COVID-19. We propose to implement routine screening of hospitalized COVID-19 patients for rapid identification of patients with IFN-AABs who most likely benefit from specific therapies.


Assuntos
COVID-19 , Interferon Tipo I , Anticorpos Neutralizantes , Autoanticorpos , COVID-19/diagnóstico , Estado Terminal , Feminino , Humanos , Interferon-alfa/uso terapêutico , Masculino , Oxigênio , SARS-CoV-2
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