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1.
Immunity ; 52(5): 734-736, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32392464

RESUMO

The emergence and rapid global spread of SARS-CoV-2 mark the third such identification of a novel coronavirus capable of causing severe, potentially fatal disease in humans in the 21st century. As noted by Andersen et al. (Nature Medicine), the sequencing of proximal zoonotic ancestors to SARS-CoV-2 has aided in the identification of alleles that may contribute to the virus' virulence in humans.


Assuntos
Infecções por Coronavirus , Coronavirus , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Betacoronavirus , COVID-19 , Humanos , Pandemias , Pneumonia Viral , SARS-CoV-2
2.
J Virol ; 98(5): e0190323, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38593045

RESUMO

We developed a novel class of peptidomimetic inhibitors targeting several host cell human serine proteases, including transmembrane protease serine 2 (TMPRSS2), matriptase, and hepsin. TMPRSS2 is a membrane-associated protease that is highly expressed in the upper and lower respiratory tracts and is utilized by SARS-CoV-2 and other viruses to proteolytically process their glycoproteins, enabling host cell entry, replication, and dissemination of new virus particles. We have previously shown that compound MM3122 exhibited subnanomolar potency against all three proteases and displayed potent antiviral effects against SARS-CoV-2 in a cell viability assay. Herein, we demonstrate that MM3122 potently inhibits viral replication in human lung epithelial cells and is also effective against the EG.5.1 variant of SARS-CoV-2. Furthermore, we evaluated MM3122 in a mouse model of COVID-19 and demonstrated that MM3122 administered intraperitoneally (IP) before (prophylactic) or after (therapeutic) SARS-CoV-2 infection had significant protective effects against weight loss and lung congestion and reduced pathology. Amelioration of COVID-19 disease was associated with a reduction in proinflammatory cytokine and chemokine production after SARS-CoV-2 infection. Prophylactic, but not therapeutic, administration of MM3122 also reduced virus titers in the lungs of SARS-CoV-2-infected mice. Therefore, MM3122 is a promising lead candidate small-molecule drug for the treatment and prevention of infections caused by SARS-CoV-2 and other coronaviruses. IMPORTANCE: SARS-CoV-2 and other emerging RNA coronaviruses are a present and future threat in causing widespread endemic and pandemic infection and disease. In this paper, we have shown that the novel host cell protease inhibitor, MM3122, blocks SARS-CoV-2 viral replication and is efficacious as both a prophylactic and a therapeutic drug for the treatment of COVID-19 given intraperitoneally in mice. Targeting host proteins and pathways in antiviral therapy is an underexplored area of research, but this approach promises to avoid drug resistance by the virus, which is common in current antiviral treatments.


Assuntos
Antivirais , Benzotiazóis , Tratamento Farmacológico da COVID-19 , Oligopeptídeos , SARS-CoV-2 , Inibidores de Serina Proteinase , Replicação Viral , Animais , Feminino , Humanos , Camundongos , Antivirais/farmacologia , Chlorocebus aethiops , COVID-19/virologia , Modelos Animais de Doenças , Pulmão/virologia , Pulmão/patologia , Pulmão/efeitos dos fármacos , Peptidomiméticos/farmacologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/fisiologia , Serina Endopeptidases/metabolismo , Inibidores de Serina Proteinase/farmacologia , Inibidores de Serina Proteinase/uso terapêutico , Células Vero , Replicação Viral/efeitos dos fármacos , Oligopeptídeos/farmacologia , Benzotiazóis/farmacologia
3.
Annu Rev Public Health ; 45(1): 359-374, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38109518

RESUMO

The financing of public health systems and services relies on a complex and fragmented web of partners and funding priorities. Both underfunding and "dys-funding" contribute to preventable mortality, increases in disease frequency and severity, and hindered social and economic growth. These issues were both illuminated and magnified by the COVID-19 pandemic and associated responses. Further complicating issues is the difficulty in constructing adequate estimates of current public health resources and necessary resources. Each of these challenges inhibits the delivery of necessary services, leads to inequitable access and resourcing, contributes to resource volatility, and presents other deleterious outcomes. However, actions may be taken to defragment complex funding paradigms toward more flexible spending, to modernize and standardize data systems, and to assure equitable and sustainable public health investments.


Assuntos
COVID-19 , Saúde Pública , Humanos , COVID-19/epidemiologia , COVID-19/economia , Financiamento Governamental , Financiamento da Assistência à Saúde , Pandemias/economia , Saúde Pública/economia , SARS-CoV-2 , Estados Unidos
4.
J Surg Res ; 297: 109-120, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38484452

RESUMO

INTRODUCTION: Health disparities in the Asian and Pacific Islander Americans (APIAs) community have not been well described, unlike non-Hispanic Black and Hispanic communities. However, there has been a rise in violence against the APIA community. This study explores and characterizes violent death by incident (e.g., homicide, suicide), weapon (e.g., firearm, strangulation), and location types among APIAs as they compare with other racial or ethnic groups. METHODS: We used the National Violent Death Reporting System from 2003 to 2018 to characterize violent deaths among APIA and compared them to all other races. We compared these racial categories in two ways. First, we compared all races as a categorical variable that included six non-Hispanic racial categories including "Other or unspecified" and "two or more races. We then created a binary variable of APIA versus All Other Races for analysis. We explored the incident type of death, substance abuse disorders, mental health history, and gang involvement among other variables. We used Chi-square tests for categorical variables and Mann-Whitney U-tests for continuous variables. RESULTS: Overall, APIAs had a unique pattern of violent death. APIAs were more likely to commit suicide (71.74%-62.21%, P<0.001) and less likely to die of homicide than other races (17.56%-24.31%, P<0.001). In the cases of homicide, APIAs were more likely to have their deaths precipitated by another crime (40.87% versus 27.87%, P < 0.001). APIAs were more than twice as likely to die of strangulation than other races (39.93%-18.06%, P<0.001). Conversely, APIAs were less likely to die by firearm than other races (29.69-51.51, P<0.001). CONCLUSIONS: APIAs have a unique pattern of violence based on analysis of data from the National Violent Death Reporting System. Our data reveal a significant difference in the incident, weapon and location type as compared to Americans of other races, which begs further inquiry into the patterns of change in time and factors that contribute to inter-racial differences in death patterns.


Assuntos
Homicídio , Havaiano Nativo ou Outro Ilhéu do Pacífico , Suicídio , Violência , Humanos , Causas de Morte , Vigilância da População , Estados Unidos
5.
BMC Health Serv Res ; 24(1): 368, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38521923

RESUMO

BACKGROUND: Individuals with unmet social needs experience adverse health outcomes and are subject to greater inequities in health and social outcomes. Given the high prevalence of unmet needs among Medicaid enrollees, many Medicaid managed care organizations (MCOs) are now screening enrollees for unmet social needs and connecting them to community-based organizations (CBOs) with knowledge and resources to address identified needs. The use of screening and referral technology and data sharing are often considered key components in programs integrating health and social services. Despite this emphasis on technology and data collection, research suggests substantial barriers exist in operationalizing effective systems. METHODS: We used qualitative methods to examine cross-sector perspectives on the use of data and technology to facilitate MCO and CBO partnerships in Kentucky, a state with high Medicaid enrollment, to address enrollee social needs. We recruited participants through targeted sampling, and conducted 46 in-depth interviews with 26 representatives from all six Kentucky MCOs and 20 CBO leaders. Qualitative descriptive analysis, an inductive approach, was used to identify salient themes. RESULTS: We found that MCOs and CBOs have differing levels of need for data, varying incentives for collecting and sharing data, and differing valuations of what data can or should do. Four themes emerged from interviewees' descriptions of how they use data, including 1) to screen for patient needs, 2) to case manage, 3) to evaluate the effectiveness of programs, and 4) to partner with each other. Underlying these data use themes were areas of alignment between MCOs/CBOs, areas of incongruence, and areas of tension (both practical and ideological). The inability to interface with community partners for data privacy and ownership concerns contributes to division. Our findings suggest a disconnect between MCOs and CBOs regarding terms of their technology interfacing despite their shared mission of meeting the unmet social needs of enrollees. CONCLUSIONS: While data and technology can be used to identify enrollee needs and determine the most critical need, it is not sufficient in resolving challenges. People and relationships across sectors are vital in connecting enrollees with the community resources to resolve unmet needs.


Assuntos
Programas de Assistência Gerenciada , Medicaid , Estados Unidos , Humanos , Serviço Social , Coleta de Dados
6.
Telemed J E Health ; 30(4): e1071-e1080, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37883644

RESUMO

Introduction: During the COVID-19 pandemic, care shifted from exclusively telemedicine to hybrid models with in-person, video, and telephone visits. We explored how patient satisfaction and visit preferences have changed by comparing in-person versus virtual visits (telephone and video) in an ambulatory neurology practice across three time points. Methods: Patients who completed a virtual visit in March 2020 (early-pandemic), May 2020 (mid-pandemic), and March 2021 (later-pandemic) were contacted. Patients were assessed for visit satisfaction and desire for future telemedicine. Univariate and multivariable logistic regression analysis was conducted to determine factors independently associated with video visit completion. Results: Four thousand seven hundred seventy-eight the number of ambulatory visits (n = 4,778) were performed (1,004 early; 1,265 mid; and 2,509 later); 1,724 patients (36%) assented to postvisit feedback; mean age 45.8 ± 24.4 years, 58% female, 79% white, and 56% with Medicare/Medicaid insurance. Patient satisfaction significantly increased (73% early, 79% mid, 81% later-pandemic, p = 0.008). Interest in telemedicine also increased for patients completing telephone visits (40% early, 50% mid, 59% later, p = 0.027) and video visits (52% early, 59% mid, 62% later, p = 0.035). Patients satisfied with telemedicine visits were younger (p < 0.001). White patients were more interested in future telemedicine (p = 0.037). Multivariable analysis showed that older patients (for each 1 year older), Black patients, and patients with Medicare/Medicaid were 2%, 45%, and 54% less likely to complete a video visit than telephone, respectively. Discussion: Patients, especially younger ones, have become more satisfied and more interested in hybrid care models during the COVID-19 pandemic. Barriers to conducting video visits persist for older, Black patients with Medicare or Medicaid insurance.


Assuntos
COVID-19 , Neurologia , Telemedicina , Estados Unidos , Humanos , Idoso , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Masculino , Satisfação do Paciente , COVID-19/epidemiologia , Pandemias , North Carolina/epidemiologia , Medicare , Satisfação Pessoal
7.
PLoS Pathog ; 17(1): e1009033, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33411764

RESUMO

The p53 transcription factor plays a key role both in cancer and in the cell-intrinsic response to infections. The ORFEOME project hypothesized that novel p53-virus interactions reside in hitherto uncharacterized, unknown, or hypothetical open reading frames (orfs) of human viruses. Hence, 172 orfs of unknown function from the emerging viruses SARS-Coronavirus, MERS-Coronavirus, influenza, Ebola, Zika (ZIKV), Chikungunya and Kaposi Sarcoma-associated herpesvirus (KSHV) were de novo synthesized, validated and tested in a functional screen of p53 signaling. This screen revealed novel mechanisms of p53 virus interactions and two viral proteins KSHV orf10 and ZIKV NS2A binding to p53. Originally identified as the target of small DNA tumor viruses, these experiments reinforce the notion that all viruses, including RNA viruses, interfere with p53 functions. These results validate this resource for analogous systems biology approaches to identify functional properties of uncharacterized viral proteins, long non-coding RNAs and micro RNAs.


Assuntos
Doenças Transmissíveis Emergentes/virologia , Vírus de RNA/metabolismo , Transdução de Sinais/genética , Proteína Supressora de Tumor p53/metabolismo , Vírus Chikungunya/genética , Vírus Chikungunya/metabolismo , Coronavirus/genética , Coronavirus/metabolismo , Ebolavirus/genética , Ebolavirus/metabolismo , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/metabolismo , Humanos , Vírus da Influenza A/genética , Vírus da Influenza A/metabolismo , Fases de Leitura Aberta , Vírus de RNA/genética , Proteína Supressora de Tumor p53/genética , Proteínas não Estruturais Virais/metabolismo , Zika virus/genética , Zika virus/metabolismo
8.
Proc Natl Acad Sci U S A ; 117(43): 26915-26925, 2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-33046644

RESUMO

Zoonotic coronaviruses represent an ongoing threat, yet the myriads of circulating animal viruses complicate the identification of higher-risk isolates that threaten human health. Swine acute diarrhea syndrome coronavirus (SADS-CoV) is a newly discovered, highly pathogenic virus that likely evolved from closely related HKU2 bat coronaviruses, circulating in Rhinolophus spp. bats in China and elsewhere. As coronaviruses cause severe economic losses in the pork industry and swine are key intermediate hosts of human disease outbreaks, we synthetically resurrected a recombinant virus (rSADS-CoV) as well as a derivative encoding tomato red fluorescent protein (tRFP) in place of ORF3. rSADS-CoV replicated efficiently in a variety of continuous animal and primate cell lines, including human liver and rectal carcinoma cell lines. Of concern, rSADS-CoV also replicated efficiently in several different primary human lung cell types, as well as primary human intestinal cells. rSADS-CoV did not use human coronavirus ACE-2, DPP4, or CD13 receptors for docking and entry. Contemporary human donor sera neutralized the group I human coronavirus NL63, but not rSADS-CoV, suggesting limited human group I coronavirus cross protective herd immunity. Importantly, remdesivir, a broad-spectrum nucleoside analog that is effective against other group 1 and 2 coronaviruses, efficiently blocked rSADS-CoV replication in vitro. rSADS-CoV demonstrated little, if any, replicative capacity in either immune-competent or immunodeficient mice, indicating a critical need for improved animal models. Efficient growth in primary human lung and intestinal cells implicate SADS-CoV as a potential higher-risk emerging coronavirus pathogen that could negatively impact the global economy and human health.


Assuntos
Alphacoronavirus/fisiologia , Infecções por Coronavirus/virologia , Suscetibilidade a Doenças/virologia , Replicação Viral , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacologia , Alanina/análogos & derivados , Alanina/farmacologia , Alphacoronavirus/genética , Alphacoronavirus/crescimento & desenvolvimento , Animais , Células Cultivadas , Chlorocebus aethiops , Infecções por Coronavirus/transmissão , Expressão Gênica , Especificidade de Hospedeiro , Humanos , Proteínas Luminescentes/genética , Camundongos , Células Vero , Replicação Viral/efeitos dos fármacos
9.
Milbank Q ; 100(1): 261-283, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35191076

RESUMO

Policy Points While the coronavirus pandemic has underscored the important role of public health systems in protecting community health, it has also exposed weaknesses in the public health infrastructure that stem from chronic underfunding and fragmentation in delivery systems. The results of our study suggest that the public health system structure can be strengthened through the targeted implementation of high-value population health capabilities. Prioritizing the delivery of value-added population health capabilities can help communities efficiently use limited time and resources and identify the most effective pathways for building a stronger public health system and improving health outcomes over time. CONTEXT: While the novel coronavirus pandemic has underscored the important role of public health systems in protecting community health, it has also exposed weaknesses in the public health infrastructure that stem from chronic underfunding and fragmentation in public health delivery systems. Information about the relative value in the implementation of recommended population health capabilities can help communities prioritize their use of limited time and resources and identify the most effective pathways for building a stronger public health system. METHODS: We used a longitudinal cohort design with data from the National Longitudinal Survey of Public Health Systems to examine longitudinal and geographic trends in the delivery of population health capabilities and their impact on system strength across communities in the United States. We used linear probability models to ascertain whether the delivery of certain capabilities added value to public health system strength. FINDINGS: Those communities with the strongest classification of public health system structure in both urban and rural areas implemented the largest set of population health capabilities. Results from the linear probability model indicate that a set of population health capabilities are associated with increased public health system strength. Key activities include allocating resources based on a community health plan, surveying the community for behavioral risk factors, analyzing the data on preventive services use, and engaging community stakeholders in health improvement planning (p < 0.01). CONCLUSIONS: The results of this study suggest that public health systems can be strengthened through the targeted implementation of high-value population health capabilities. Prioritizing the delivery of value-added population health capabilities may help communities increase their public health system's capacity and improve health outcomes.


Assuntos
COVID-19 , Saúde da População , COVID-19/epidemiologia , COVID-19/prevenção & controle , Planejamento em Saúde , Humanos , Estudos Longitudinais , Saúde Pública , Estados Unidos/epidemiologia
10.
J Public Health Manag Pract ; 28(6): E808-E814, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36037519

RESUMO

OBJECTIVE: The purpose of this study was to examine patterns of cross-jurisdictional sharing across the 61 local public health jurisdictions (LHJs) in Kentucky. The opportunities to reduce the cost-of-service delivery for Kentucky's LHJs via cross-jurisdictional sharing present a mechanism to address financial instability across the state by achieving economies of scale, especially among smaller jurisdictions. DESIGN: A cross-sectional study design was used to examine patterns of cross-jurisdictional sharing across the 61 LHJs in Kentucky. The survey tool utilized was designed by the Center for Sharing Public Health Services, an initiative managed by the Kansas Health Institute with support from the Robert Wood Johnson Foundation. RESULTS: Seventy-two percent of the 61 LHJs in Kentucky responded to the survey. The majority of responding jurisdictions sharing services were rural, single-county jurisdictions, utilizing service-related informal sharing arrangements. The majority of health departments, when asked to identify which programmatic areas shared service arrangements were focused in, listed those services requiring intensive staff training such as Health Access Nurturing Development Services (HANDS) and epidemiology. Of particular interest were the services most infrequently shared such as communicable disease screening and treatment. CONCLUSIONS: This study suggests that, pre-COVID-19, a core group of primarily rural, single-county Kentucky local health departments has experience with cross-jurisdictional sharing. Among this group, engagement in informal arrangements was the form of cross-jurisdictional sharing predominantly used, with few jurisdictions reporting shared functions with joint oversight. When considering the potential benefits and efficiencies that cross-jurisdictional sharing can provide to public health departments and their communities, for some, COVID-19 may have been a catalyst to engage in sharing across health department jurisdictional lines.


Assuntos
COVID-19 , COVID-19/epidemiologia , Estudos Transversais , Humanos , Kentucky , Programas de Rastreamento , Saúde Pública
11.
J Virol ; 94(7)2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-31996437

RESUMO

Recently, a novel coronavirus (2019-nCoV) has emerged from Wuhan, China, causing symptoms in humans similar to those caused by severe acute respiratory syndrome coronavirus (SARS-CoV). Since the SARS-CoV outbreak in 2002, extensive structural analyses have revealed key atomic-level interactions between the SARS-CoV spike protein receptor-binding domain (RBD) and its host receptor angiotensin-converting enzyme 2 (ACE2), which regulate both the cross-species and human-to-human transmissions of SARS-CoV. Here, we analyzed the potential receptor usage by 2019-nCoV, based on the rich knowledge about SARS-CoV and the newly released sequence of 2019-nCoV. First, the sequence of 2019-nCoV RBD, including its receptor-binding motif (RBM) that directly contacts ACE2, is similar to that of SARS-CoV, strongly suggesting that 2019-nCoV uses ACE2 as its receptor. Second, several critical residues in 2019-nCoV RBM (particularly Gln493) provide favorable interactions with human ACE2, consistent with 2019-nCoV's capacity for human cell infection. Third, several other critical residues in 2019-nCoV RBM (particularly Asn501) are compatible with, but not ideal for, binding human ACE2, suggesting that 2019-nCoV has acquired some capacity for human-to-human transmission. Last, while phylogenetic analysis indicates a bat origin of 2019-nCoV, 2019-nCoV also potentially recognizes ACE2 from a diversity of animal species (except mice and rats), implicating these animal species as possible intermediate hosts or animal models for 2019-nCoV infections. These analyses provide insights into the receptor usage, cell entry, host cell infectivity and animal origin of 2019-nCoV and may help epidemic surveillance and preventive measures against 2019-nCoV.IMPORTANCE The recent emergence of Wuhan coronavirus (2019-nCoV) puts the world on alert. 2019-nCoV is reminiscent of the SARS-CoV outbreak in 2002 to 2003. Our decade-long structural studies on the receptor recognition by SARS-CoV have identified key interactions between SARS-CoV spike protein and its host receptor angiotensin-converting enzyme 2 (ACE2), which regulate both the cross-species and human-to-human transmissions of SARS-CoV. One of the goals of SARS-CoV research was to build an atomic-level iterative framework of virus-receptor interactions to facilitate epidemic surveillance, predict species-specific receptor usage, and identify potential animal hosts and animal models of viruses. Based on the sequence of 2019-nCoV spike protein, we apply this predictive framework to provide novel insights into the receptor usage and likely host range of 2019-nCoV. This study provides a robust test of this reiterative framework, providing the basic, translational, and public health research communities with predictive insights that may help study and battle this novel 2019-nCoV.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/virologia , Peptidil Dipeptidase A/química , Pneumonia Viral/virologia , Receptores Virais/química , Glicoproteína da Espícula de Coronavírus/química , Sequência de Aminoácidos , Enzima de Conversão de Angiotensina 2 , Animais , Betacoronavirus/classificação , COVID-19 , China , Quirópteros/virologia , Especificidade de Hospedeiro , Humanos , Modelos Moleculares , Filogenia , Domínios Proteicos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/fisiologia , SARS-CoV-2 , Alinhamento de Sequência
12.
J Virol ; 94(5)2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-31801868

RESUMO

Traditionally, the emergence of coronaviruses (CoVs) has been attributed to a gain in receptor binding in a new host. Our previous work with severe acute respiratory syndrome (SARS)-like viruses argued that bats already harbor CoVs with the ability to infect humans without adaptation. These results suggested that additional barriers limit the emergence of zoonotic CoV. In this work, we describe overcoming host restriction of two Middle East respiratory syndrome (MERS)-like bat CoVs using exogenous protease treatment. We found that the spike protein of PDF2180-CoV, a MERS-like virus found in a Ugandan bat, could mediate infection of Vero and human cells in the presence of exogenous trypsin. We subsequently show that the bat virus spike can mediate the infection of human gut cells but is unable to infect human lung cells. Using receptor-blocking antibodies, we show that infection with the PDF2180 spike does not require MERS-CoV receptor DPP4 and antibodies developed against the MERS spike receptor-binding domain and S2 portion are ineffective in neutralizing the PDF2180 chimera. Finally, we found that the addition of exogenous trypsin also rescues HKU5-CoV, a second bat group 2c CoV. Together, these results indicate that proteolytic cleavage of the spike, not receptor binding, is the primary infection barrier for these two group 2c CoVs. Coupled with receptor binding, proteolytic activation offers a new parameter to evaluate the emergence potential of bat CoVs and offers a means to recover previously unrecoverable zoonotic CoV strains.IMPORTANCE Overall, our studies demonstrate that proteolytic cleavage is the primary barrier to infection for a subset of zoonotic coronaviruses. Moving forward, the results argue that both receptor binding and proteolytic cleavage of the spike are critical factors that must be considered for evaluating the emergence potential and risk posed by zoonotic coronaviruses. In addition, the findings also offer a novel means to recover previously uncultivable zoonotic coronavirus strains and argue that other tissues, including the digestive tract, could be a site for future coronavirus emergence events in humans.


Assuntos
Coronavírus da Síndrome Respiratória do Oriente Médio/química , Coronavírus da Síndrome Respiratória do Oriente Médio/metabolismo , Receptores Virais/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Animais , Células CACO-2 , Quirópteros , Chlorocebus aethiops , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/virologia , Humanos , Tripsina , Células Vero , Zoonoses/metabolismo , Zoonoses/virologia
13.
J Virol ; 93(2)2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30355694

RESUMO

Emergent strains of human norovirus seed pandemic waves of disease. These new strains have altered ligand binding and antigenicity characteristics. Study of viral variants isolated from immunosuppressed patients with long-term norovirus infection indicates that initial virus in vivo evolution occurs at the same antigenic sites as in pandemic strains. Here, cellular ligand binding and antigenicity of two cocirculating strains isolated from a patient with long-term norovirus infection were characterized. The isolated GII.4 viruses differed from previous strains and from each other at known blockade antibody epitopes. One strain had a unique sequence in epitope D, including loss of an insertion at residue 394, corresponding to a decreased relative affinity for carbohydrate ligands. Replacement of 394 with alanine or restoration of the contemporary strain epitope D consensus sequence STT improved ligand binding relative affinity. However, monoclonal antibody blockade of binding potency was only gained for the consensus sequence, not by the alanine insertion. In-depth study of unique changes in epitope D indicated that ligand binding, but not antibody blockade of ligand binding, is maintained despite sequence diversity, allowing escape from blockade antibodies without loss of capacity for binding cellular ligands.IMPORTANCE Human norovirus causes ∼20% of all acute gastroenteritis and ∼200,000 deaths per year, primarily in young children. Most epidemic and all pandemic waves of disease over the past 30 years have been caused by type GII.4 human norovirus strains. The capsid sequence of GII.4 strains is changing over time, resulting in viruses with altered ligand and antibody binding characteristics. The carbohydrate binding pocket of these strains does not vary over time. Here, utilizing unique viral sequences, we study how residues in GII.4 epitope D balance the dual roles of variable antibody binding site and cellular ligand binding stabilization domain, demonstrating that amino acid changes in epitope D can result in loss of antibody binding without ablating ligand binding. This flexibility in epitope D likely contributes to GII.4 strain persistence by both allowing escape from antibody-mediated herd immunity and maintenance of cellular ligand binding and infectivity.


Assuntos
Anticorpos Bloqueadores/metabolismo , Infecções por Caliciviridae/imunologia , Proteínas do Capsídeo/genética , Epitopos/imunologia , Mutação INDEL , Norovirus/isolamento & purificação , Anticorpos Antivirais/metabolismo , Infecções por Caliciviridae/virologia , Proteínas do Capsídeo/química , Proteínas do Capsídeo/imunologia , Criança , Epitopos/genética , Fezes/virologia , Humanos , Imunidade Coletiva , Ligantes , Norovirus/genética , Norovirus/imunologia , Ligação Proteica
14.
Proc Natl Acad Sci U S A ; 114(42): E8895-E8904, 2017 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-29073030

RESUMO

Members of the order Nidovirales express their structural protein ORFs from a nested set of 3' subgenomic mRNAs (sg mRNAs), and for most of these ORFs, a single genomic transcription regulatory sequence (TRS) was identified. Nine TRSs were previously reported for the arterivirus Simian hemorrhagic fever virus (SHFV). In the present study, which was facilitated by next-generation sequencing, 96 SHFV body TRSs were identified that were functional in both infected MA104 cells and macaque macrophages. The abundance of sg mRNAs produced from individual TRSs was consistent over time in the two different cell types. Most of the TRSs are located in the genomic 3' region, but some are in the 5' ORF1a/1b region and provide alternative sources of nonstructural proteins. Multiple functional TRSs were identified for the majority of the SHFV 3' ORFs, and four previously identified TRSs were found not to be the predominant ones used. A third of the TRSs generated sg mRNAs with variant leader-body junction sequences. Sg mRNAs encoding E', GP2, or ORF5a as their 5' ORF as well as sg mRNAs encoding six previously unreported alternative frame ORFs or 14 previously unreported C-terminal ORFs of known proteins were also identified. Mutation of the start codon of two C-terminal ORFs in an infectious clone reduced virus yield. Mass spectrometry detected one previously unreported protein and suggested translation of some of the C-terminal ORFs. The results reveal the complexity of the transcriptional regulatory mechanism and expanded coding capacity for SHFV, which may also be characteristic of other nidoviruses.


Assuntos
Nidovirales/genética , Nidovirales/patogenicidade , RNA Mensageiro/genética , Sequências Reguladoras de Ácido Ribonucleico , Animais , Northern Blotting , Chlorocebus aethiops , Códon de Iniciação , Genoma Viral , Macaca , Mutação , Infecções por Nidovirales/genética , Fases de Leitura Aberta , RNA Viral , Proteínas Virais/análise , Proteínas Estruturais Virais/genética
15.
J Virol ; 92(17)2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29976657

RESUMO

With an ongoing threat posed by circulating zoonotic strains, new strategies are required to prepare for the next emergent coronavirus (CoV). Previously, groups had targeted conserved coronavirus proteins as a strategy to generate live attenuated vaccine strains against current and future CoVs. With this in mind, we explored whether manipulation of CoV NSP16, a conserved 2'O methyltransferase (MTase), could provide a broad attenuation platform against future emergent strains. Using the severe acute respiratory syndrome-CoV mouse model, an NSP16 mutant vaccine was evaluated for protection from heterologous challenge, efficacy in the aging host, and potential for reversion to pathogenesis. Despite some success, concerns for virulence in the aged and potential for reversion makes targeting NSP16 alone an untenable approach. However, combining a 2'O MTase mutation with a previously described CoV fidelity mutant produced a vaccine strain capable of protection from heterologous virus challenge, efficacy in aged mice, and no evidence for reversion. Together, the results indicate that targeting the CoV 2'O MTase in parallel with other conserved attenuating mutations may provide a platform strategy for rapidly generating live attenuated coronavirus vaccines.IMPORTANCE Emergent coronaviruses remain a significant threat to global public health and rapid response vaccine platforms are needed to stem future outbreaks. However, failure of many previous CoV vaccine formulations has clearly highlighted the need to test efficacy under different conditions and especially in vulnerable populations such as the aged and immunocompromised. This study illustrates that despite success in young models, the 2'O methyltransferase mutant carries too much risk for pathogenesis and reversion in vulnerable models to be used as a stand-alone vaccine strategy. Importantly, the 2'O methyltransferase mutation can be paired with other attenuating approaches to provide robust protection from heterologous challenge and in vulnerable populations. Coupled with increased safety and reduced pathogenesis, the study highlights the potential for 2'O methyltransferase attenuation as a major component of future live attenuated coronavirus vaccines.


Assuntos
Infecções por Coronavirus/prevenção & controle , Coronavirus/imunologia , Metiltransferases/genética , Proteínas não Estruturais Virais/genética , Vacinas Virais/genética , Envelhecimento/imunologia , Animais , Proteínas Arqueais/genética , Chlorocebus aethiops , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Modelos Animais de Doenças , Hospedeiro Imunocomprometido , Metilação , Metiltransferases/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Mutação , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Células Vero , Proteínas não Estruturais Virais/imunologia , Vacinas Virais/imunologia , Replicação Viral
16.
Proc Natl Acad Sci U S A ; 113(11): 3048-53, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26976607

RESUMO

Outbreaks from zoonotic sources represent a threat to both human disease as well as the global economy. Despite a wealth of metagenomics studies, methods to leverage these datasets to identify future threats are underdeveloped. In this study, we describe an approach that combines existing metagenomics data with reverse genetics to engineer reagents to evaluate emergence and pathogenic potential of circulating zoonotic viruses. Focusing on the severe acute respiratory syndrome (SARS)-like viruses, the results indicate that the WIV1-coronavirus (CoV) cluster has the ability to directly infect and may undergo limited transmission in human populations. However, in vivo attenuation suggests additional adaptation is required for epidemic disease. Importantly, available SARS monoclonal antibodies offered success in limiting viral infection absent from available vaccine approaches. Together, the data highlight the utility of a platform to identify and prioritize prepandemic strains harbored in animal reservoirs and document the threat posed by WIV1-CoV for emergence in human populations.


Assuntos
Quirópteros/virologia , Doenças Transmissíveis Emergentes/virologia , Infecções por Coronaviridae/virologia , Coronaviridae/patogenicidade , Enzima de Conversão de Angiotensina 2 , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Células Cultivadas , Chlorocebus aethiops , Coronaviridae/genética , Coronaviridae/imunologia , Coronaviridae/isolamento & purificação , Coronaviridae/fisiologia , Infecções por Coronaviridae/prevenção & controle , Infecções por Coronaviridae/transmissão , Infecções por Coronaviridae/veterinária , Reações Cruzadas , Encefalite Viral/virologia , Células Epiteliais/virologia , Especificidade de Hospedeiro , Humanos , Pulmão/citologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Modelos Moleculares , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/fisiologia , Mutação Puntual , Conformação Proteica , Receptores Virais/genética , Receptores Virais/fisiologia , Proteínas Recombinantes de Fusão/metabolismo , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia , Especificidade da Espécie , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/fisiologia , Células Vero , Replicação Viral , Zoonoses
17.
Proc Natl Acad Sci U S A ; 111(19): E2018-26, 2014 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-24778221

RESUMO

The newly emerging Middle East Respiratory Syndrome coronavirus (MERS-CoV) causes a Severe Acute Respiratory Syndrome-like disease with ∼43% mortality. Given the recent detection of virus in dromedary camels, zoonotic transfer of MERS-CoV to humans is suspected. In addition, little is known about the role of human neutralizing Ab (nAb) pressure as a driving force in MERS-CoV adaptive evolution. Here, we used a well-characterized nonimmune human Ab-phage library and a panning strategy with proteoliposomes and cells to identify seven human nAbs against the receptor-binding domain (RBD) of the MERS-CoV Spike protein. These nAbs bind to three different epitopes in the RBD and human dipeptidyl peptidase 4 (hDPP4) interface with subnanomolar/nanomolar binding affinities and block the binding of MERS-CoV Spike protein with its hDPP4 receptor. Escape mutant assays identified five amino acid residues that are critical for neutralization escape. Despite the close proximity of the three epitopes on the RBD interface, escape from one epitope did not have a major impact on neutralization with Abs directed to a different epitope. Importantly, the majority of escape mutations had negative impacts on hDPP4 receptor binding and viral fitness. To our knowledge, these results provide the first report on human nAbs against MERS-CoV that may contribute to MERS-CoV clearance and evolution. Moreover, in the absence of a licensed vaccine or antiviral for MERS, this panel of nAbs offers the possibility of developing human mAb-based immunotherapy, especially for health-care workers.


Assuntos
Anticorpos Neutralizantes/isolamento & purificação , Anticorpos Antivirais/isolamento & purificação , Infecções por Coronavirus/imunologia , Coronavirus/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Antivirais/imunologia , Antivirais/isolamento & purificação , Evolução Biológica , Doenças Transmissíveis Emergentes/tratamento farmacológico , Doenças Transmissíveis Emergentes/imunologia , Doenças Transmissíveis Emergentes/mortalidade , Coronavirus/genética , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/mortalidade , Dipeptidil Peptidase 4/imunologia , Células HEK293 , Humanos , Imunoglobulina G/imunologia , Dados de Sequência Molecular , Filogenia , Glicoproteína da Espícula de Coronavírus/genética , Zoonoses/tratamento farmacológico , Zoonoses/imunologia , Zoonoses/mortalidade
18.
Proc Natl Acad Sci U S A ; 110(40): 16157-62, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24043791

RESUMO

Severe acute respiratory syndrome with high mortality rates (~50%) is associated with a novel group 2c betacoronavirus designated Middle East respiratory syndrome coronavirus (MERS-CoV). We synthesized a panel of contiguous cDNAs that spanned the entire genome. Following contig assembly into genome-length cDNA, transfected full-length transcripts recovered several recombinant viruses (rMERS-CoV) that contained the expected marker mutations inserted into the component clones. Because the wild-type MERS-CoV contains a tissue culture-adapted T1015N mutation in the S glycoprotein, rMERS-CoV replicated ~0.5 log less efficiently than wild-type virus. In addition, we ablated expression of the accessory protein ORF5 (rMERS•ORF5) and replaced it with tomato red fluorescent protein (rMERS-RFP) or deleted the entire ORF3, 4, and 5 accessory cluster (rMERS-ΔORF3-5). Recombinant rMERS-CoV, rMERS-CoV•ORF5, and MERS-CoV-RFP replicated to high titers, whereas MERS-ΔORF3-5 showed 1-1.5 logs reduced titer compared with rMERS-CoV. Northern blot analyses confirmed the associated molecular changes in the recombinant viruses, and sequence analysis demonstrated that RFP was expressed from the appropriate consensus sequence AACGAA. We further show dipeptidyl peptidase 4 expression, MERS-CoV replication, and RNA and protein synthesis in human airway epithelial cell cultures, primary lung fibroblasts, primary lung microvascular endothelial cells, and primary alveolar type II pneumocytes, demonstrating a much broader tissue tropism than severe acute respiratory syndrome coronavirus. The availability of a MERS-CoV molecular clone, as well as recombinant viruses expressing indicator proteins, will allow for high-throughput testing of therapeutic compounds and provide a genetic platform for studying gene function and the rational design of live virus vaccines.


Assuntos
Doenças Transmissíveis Emergentes/virologia , Coronavirus/genética , DNA Complementar/genética , Síndrome Respiratória Aguda Grave/virologia , Northern Blotting , Western Blotting , Células Cultivadas , Primers do DNA/genética , Dipeptidil Peptidase 4/metabolismo , Regulação Viral da Expressão Gênica/genética , Regulação Viral da Expressão Gênica/fisiologia , Humanos , Proteínas Luminescentes , Oriente Médio , Polimorfismo de Fragmento de Restrição , Reação em Cadeia da Polimerase em Tempo Real , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/fisiologia , Ligação Viral , Replicação Viral/fisiologia , Proteína Vermelha Fluorescente
19.
J Nurs Adm ; 46(5): 257-64, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27046742

RESUMO

OBJECTIVE: This study examined the impact of shared governance (SG) on the professional nursing practice environment of a small community hospital over time. BACKGROUND: Shared governance has been shown to empower nurses in direct patient care to make decisions about their practice and improve job satisfaction. No research has been found that examined the progression of SG over time in a small community hospital. METHODS: Questionnaires pertaining to the professional practice environment, perception of nursing leadership, nurse empowerment, nurse satisfaction, risk of practice errors, and comfort with evidence-based practice were administered to all nurses employed at a 149-bed community hospital in central North Carolina for 5 consecutive years. RESULTS: Results showed that nursing leadership and SG explained 90% of the variance in the nursing professional practice environment. This relationship held true for 5 years. All variables showed continued improvement for 4 years, until year 5 when the organization experienced disruptive change. Even during this year, the results did not return to baseline. CONCLUSIONS: In order to improve the professional practice environment of nurses, hospitals should focus on strong nursing leadership and a sound SG infrastructure.


Assuntos
Enfermagem Baseada em Evidências/normas , Hospitais Comunitários/organização & administração , Liderança , Recursos Humanos de Enfermagem Hospitalar/organização & administração , Autonomia Profissional , Tomada de Decisões , Humanos , Satisfação no Emprego , Modelos Lineares , Estudos Longitudinais , Modelos de Enfermagem , Modelos Organizacionais , North Carolina , Pesquisa em Administração de Enfermagem , Recursos Humanos de Enfermagem Hospitalar/psicologia , Cultura Organizacional , Segurança do Paciente , Inquéritos e Questionários
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