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1.
J Virol ; 98(5): e0190123, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38629840

RESUMO

Many viruses inhibit general host gene expression to limit innate immune responses and gain preferential access to the cellular translational apparatus for their protein synthesis. This process is known as host shutoff. Influenza A viruses (IAVs) encode two host shutoff proteins: nonstructural protein 1 (NS1) and polymerase acidic X (PA-X). NS1 inhibits host nuclear pre-messenger RNA maturation and export, and PA-X is an endoribonuclease that preferentially cleaves host spliced nuclear and cytoplasmic messenger RNAs. Emerging evidence suggests that in circulating human IAVs NS1 and PA-X co-evolve to ensure optimal magnitude of general host shutoff without compromising viral replication that relies on host cell metabolism. However, the functional interplay between PA-X and NS1 remains unexplored. In this study, we sought to determine whether NS1 function has a direct effect on PA-X activity by analyzing host shutoff in A549 cells infected with wild-type or mutant IAVs with NS1 effector domain deletion. This was done using conventional quantitative reverse transcription polymerase chain reaction techniques and direct RNA sequencing using nanopore technology. Our previous research on the molecular mechanisms of PA-X function identified two prominent features of IAV-infected cells: nuclear accumulation of cytoplasmic poly(A) binding protein (PABPC1) and increase in nuclear poly(A) RNA abundance relative to the cytoplasm. Here we demonstrate that NS1 effector domain function augments PA-X host shutoff and is necessary for nuclear PABPC1 accumulation. By contrast, nuclear poly(A) RNA accumulation is not dependent on either NS1 or PA-X-mediated host shutoff and is accompanied by nuclear retention of viral transcripts. Our study demonstrates for the first time that NS1 and PA-X may functionally interact in mediating host shutoff.IMPORTANCERespiratory viruses including the influenza A virus continue to cause annual epidemics with high morbidity and mortality due to the limited effectiveness of vaccines and antiviral drugs. Among the strategies evolved by viruses to evade immune responses is host shutoff-a general blockade of host messenger RNA and protein synthesis. Disabling influenza A virus host shutoff is being explored in live attenuated vaccine development as an attractive strategy for increasing their effectiveness by boosting antiviral responses. Influenza A virus encodes two proteins that function in host shutoff: the nonstructural protein 1 (NS1) and the polymerase acidic X (PA-X). We and others have characterized some of the NS1 and PA-X mechanisms of action and the additive effects that these viral proteins may have in ensuring the blockade of host gene expression. In this work, we examined whether NS1 and PA-X functionally interact and discovered that NS1 is required for PA-X to function effectively. This work significantly advances our understanding of influenza A virus host shutoff and identifies new potential targets for therapeutic interventions against influenza and further informs the development of improved live attenuated vaccines.


Assuntos
Vírus da Influenza A , Proteínas não Estruturais Virais , Humanos , Células A549 , Interações Hospedeiro-Patógeno , Vírus da Influenza A/genética , Influenza Humana/virologia , Influenza Humana/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas não Estruturais Virais/metabolismo , Proteínas não Estruturais Virais/genética , Replicação Viral , Interações Hospedeiro-Parasita
2.
Wiad Lek ; 77(2): 305-310, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38592994

RESUMO

OBJECTIVE: Aim: To determine the possibility of predicting adverse cardiovascular events based on the analysis of clinical and instrumental research methods, as well as sST2 in patients after myocardial infarction. PATIENTS AND METHODS: Materials and Methods: The study included 64 patients who suffered an acute myocardial infarction and underwent PCI with balloon angioplasty and stenting of the infarct-related vessel in the acute period. The predictors of adverse cardiovascular events were assessed events during 1 year of observation. Indicators of echocardiography and coronary angiography were assessed and concentrations sST2. RESULTS: Results: A worse prognosis was associated with intermediate ejection fraction (EF) (odds ratio (OR)=3.981, p<0.05), left aneurysm ventricle (LV) (OR=29.5, p<0.05), high concentrations of sST2 (OR=1.017, p<0.05) and scores on the Syntax scale (OR=1.001, p<0.05). CONCLUSION: Conclusions: In patients who underwent percutaneous coronary intervention for myocardial infarction, adverse outcome during the next 2 years is associated with coronary and echocardiographic parameters, as well as biochemical indicators of myocardial stress and fibrosis. HF patients with intermediate EF, LV aneurysm, high sST2 concentrations, and high Syntax scores have the worst prognosis.


Assuntos
Aneurisma , Angioplastia Coronária com Balão , Infarto do Miocárdio , Intervenção Coronária Percutânea , Humanos , Prognóstico , Resultado do Tratamento , Função Ventricular Esquerda
3.
Viruses ; 16(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38399988

RESUMO

Viruses evolve many strategies to ensure the efficient synthesis of their proteins. One such strategy is the inhibition of the integrated stress response-the mechanism through which infected cells arrest translation through the phosphorylation of the alpha subunit of the eukaryotic translation initiation factor 2 (eIF2α). We have recently shown that the human common cold betacoronavirus OC43 actively inhibits eIF2α phosphorylation in response to sodium arsenite, a potent inducer of oxidative stress. In this work, we examined the modulation of integrated stress responses by OC43 and demonstrated that the negative feedback regulator of eIF2α phosphorylation GADD34 is strongly induced in infected cells. However, the upregulation of GADD34 expression induced by OC43 was independent from the activation of the integrated stress response and was not required for the inhibition of eIF2α phosphorylation in virus-infected cells. Our work reveals a complex interplay between the common cold coronavirus and the integrated stress response, in which efficient viral protein synthesis is ensured by the inhibition of eIF2α phosphorylation but the GADD34 negative feedback loop is disrupted.


Assuntos
Betacoronavirus , Resfriado Comum , Humanos , Betacoronavirus/metabolismo , Proteína Fosfatase 1/metabolismo , Proteínas/metabolismo , Fosforilação , Biossíntese de Proteínas , Fator de Iniciação 2 em Eucariotos/metabolismo , eIF-2 Quinase/genética
4.
Alcohol Clin Exp Res (Hoboken) ; 47(12): 2233-2247, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38151780

RESUMO

BACKGROUND: Excess reactive oxygen species generated by NADPH oxidase 2 (Nox2) in response to ethanol exposure mediate aspects of skeletal toxicity including increased osteoclast differentiation and activity. Because perturbation of chondrocyte differentiation in the growth plate by ethanol could be prevented by dietary antioxidants, we hypothesized that Nox2 in the growth plate was involved in ethanol-associated reductions in longitudinal bone growth. METHODS: Nox2 conditional knockout mice were generated, where the essential catalytic subunit of Nox2, cytochrome B-245 beta chain (Cybb), is deleted in chondrocytes using a Cre-Lox model with Cre expressed from the collagen 2a1 promoter (Col2a1-Cre). Wild-type and Cre-Lox mice were fed an ethanol Lieber-DeCarli-based diet or pair-fed a control diet for 8 weeks. RESULTS: Ethanol treatment significantly reduced the number of proliferating chondrocytes in the growth plate, enhanced bone marrow adiposity, shortened femurs, reduced body length, reduced cortical bone volume, and decreased mRNA levels of a number of osteoblast and chondrocyte genes. Conditional knockout of Nox2 enzymatic activity in chondrocytes did not consistently prevent any ethanol effects. Rather, knockout mice had fewer proliferating chondrocytes than wild-type mice in both the ethanol- and control-fed animals. Additional analysis of tibia samples from Nox4 knockout mice showed that loss of Nox4 activity also reduced the number of proliferating chondrocytes and altered chondrocyte size in the growth plate. CONCLUSIONS: Although Nox enzymatic activity regulates growth plate development, ethanol-associated disruption of the growth plate morphology is independent of ethanol-mediated increases in Nox2 activity.

5.
Rev. salud pública ; 22(6): e200, nov.-dic. 2020.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1252088

RESUMO

RESUMEN La crisis sanitaria mundial que enfrenta el mundo debido al COVID-19 tiene como característica principal que afecta la población más vulnerable. La principal vía de contagio de esta enfermedad es la transmisión aérea debido al contacto social. Los países adoptaron una serie de intervenciones focalizadas para mitigar las consecuencias derivadas de esta pandemia e impactar significativamente en el bienestar de las personas. No obstante, se deben fortalecer acciones que favorezcan la capacidad resolutiva en el primer nivel de atención, especialmente, en poblaciones de alta vulnerabilidad, entre ellas, las personas en situación de discapacidad, cuyas circunstancias tienden a complicarse. La rehabilitación basada en comunidad ha sido una estrategia de gran impacto social que integra una serie de factores tanto individuales como colectivos. La eficacia y efectividad de la participación intersectorial, comunitaria y de los Gobiernos locales, así como la gestión de los diferentes agentes comunitarios para darle continuidad a los procesos de atención en salud son pertinentes para amortiguar situaciones de alta complejidad que alteran, en mayor medida, el bienestar de todas las personas. Además, contribuyen a potencializar acciones para gestionar el sistema de salud.


ABSTRACT As main feature, the global health crisis due to COVID-19 affects the most vulnerable groups of people. The main way of contagion of this disease is the airway transmission by social contact. Countries take steps to reduce the consequences of the pandemic and significantly improve the well-being of the people. However, they must boost measurements to support the capacity to resolve situations at the first level of assistance, mainly for the people that are so vulnerable: persons with disabilities, that get everyday worse. The Community Based Rehabilitation has been a strategy that group together collective and individual factors. The effectiveness and efficacy of the involvement of different groups, community, and local government, as well as management of the different community agents to give continuity to the health care processes, they are relevant to mitigate problems that affect, to a greater extent, the well-being of people. Besides, they strengthen actions to manage the health system.

6.
Rev. MED ; 26(2): 22-28, jul.-dic. 2018. tab
Artigo em Espanhol | LILACS | ID: biblio-1115206

RESUMO

Resumen Objetivo: Determinar la prevalencia de uropatógenos, sensibilidad y resistencia antimicrobiana en la infección del tracto urinario que acuden al Hospital Básico Privado "Provida" del 1 de enero de 2014 al 31 de diciembre de 2016. Material y métodos: Se analizaron los resultados de 116 urocultivos de orina en mujeres no gestantes de todas las edades de 2014 a 2016, que fueron atendidas en el Hospital Básico Privado "Provida" de la cuidad de Latacunga, en Ecuador. El análisis de los datos obtenidos se realizó mediante estadística descriptiva. Resultados: De las 116 muestras, se aislaron: Escherichia coli (84,5%), Staphylococcus saprophyticus (8,6%) y Proteus spp. (6,9%). E. coli mostró sensibilidad a ceftriaxona en el 70 %, seguido de fosfomicina y gentamicina con el 62 y el 60%, respectivamente. La sensibilidad hallada para quinolonas fue del 40% y la ampicilina sulbactam alcanzó el 37%. Proteus spp. mostró sensibilidad del 75% para gentamicina y del 50% para quinolonas y cefuroxima. S. saprophyticus tuvo sensibilidad superior al 50% para gentamicina, ampicilina sulbactam, quinolonas y nitrofurantoína. Para E. coli la resistencia más alta registrada fue con ampicilina en el 86,5%, seguido de las quinolonas con una resistencia superior al 50%. La ampicilina asociada a inhibidor de betalactamasas, fosfomicina, cefalosporinas, nitrofurantoína y aminoglucósidos mostró resistencia inferior al 25%. Conclusión: El agente patógeno más prevalente en infecciones del tracto urinario (ITU) es E. coli (84,7%), porcentaje coincidente con lo reportado en la literatura nacional y mundial. Los antimicrobianos para este uropatógeno con mayor resistencia fueron ampicilina (86%), cirprofloxacina (55%) y norfloxacina (53%). Se podría tener en cuenta en el momento de administrar una terapéutica empírica, dato que debería ser corroborado con información de susceptibilidades de acuerdo con el contexto.


Summary Objective: To determine the prevalence of uropathogens, sensitivity and antimicrobial resistance in urinary tract infections that go to the Private Basic Hospital "Provida" from January 1, 2014 to December 31, 2016. Material and methods: The results of 116 urine cultures in non-pregnant women of all ages from 2014 to 2016, which were treated at the Private Basic Hospital "Provida" of the city of Latacunga, in Ecuador, were analyzed. The data obtained was analyzed using descriptive statistics. Results: In the 116 samples, Escherichia coli (84.5%), Staphylococcus saprophyticus (8.6%) and Proteus spp. (6.9%) were isolated. E. coli showed sensitivity to ceftriaxone in 70%, followed by fosfomycin and gentamicin with 62 and 60%, respectively. The sensitivity found for quinolones was 40% and for sulbactam ampicillin reached a 37%. Proteus spp. showed sensitivity of 75% for gentamicin and 50% for quinolones and cefuroxime. S. saprophyticus had a sensitivity greater than 50% for gentamicin, sulbactam ampicillin, quinolones and nitrofurantoin. For E. coli the highest resistance recorded was found on ampicillin in 86.5%, followed by quinolones with a resistance greater than 50%. Ampicillin associated with inhibitor of beta-lactamase, fosfomycin, cephalosporins, nitrofurantoin and aminoglycosides showed a resistance below 25%. Conclusion: The most prevalent pathogen in urinary tract infections (UTI) is E. coli (84.7%), a percentage that matches what has been reported in national and world literature. The antimicrobials for this uropathogen with the highest resistance were ampicillin (86%), ciprofloxacin (55%) and norfloxacin (53%). This should be taken into account when administering an empiric therapy, even though this data should be corroborated with the susceptibility information depending on the context.


Resumo Objetivo: Determinar a prevalência de uropatógenos, sensibilidade e resistência antimicrobiana na infecção do trato urinário que vão ao Hospital Básico Privado "Provida" de 1 de janeiro de 2014 a 31 de dezembro de 2016. Material e métodos: Analisaram-se os resultados de 116 uroculturas de urina em mulheres não gestantes de todas as idades de 2014 a 2016, que foram atendidas no Hospital Básico Privado "Provida" da cidade de Latacunga, no Equador. A análise dos dados obtidos realizou-se mediante estatística descritiva. Resultados: Das 116 amostras, isolaram-se: Escherichia coli (84,5%), Staphylococcus saprophyticus (8,6%) e Proteus spp. (6,9%). E. coli mostrou sensibilidade a ceftriaxona em 70 %, seguido de fosfomicina e gentamicina com 62 e 60%, respectivamente. A sensibilidade encontrada para quinolonas foi de 40% e a ampicilina sulbactam atingiu 37%. Proteus spp. mostrou sensibilidade de 75% para gentamicina e de 50% para quinolonas e cefuroxima. S. saprophyticus teve sensibilidade superior a 50% para gentamicina, ampicilina sulbac-tam, quinolonas e nitrofurantoína. Para E. coli a resistência mais alta registrada foi com ampicilina em 86,5%, seguido das quinolonas com uma resistência superior a 50%. A ampicilina associada a inibidor de betalactamasas, fosfomicina, cefalosporinas, nitrofurantoína e aminoglucósidos mostrou resistência inferior a 25%. Conclusão: O agente patogénico mais prevalente em infecções do trato urinário (ITU) é E. coli (84,7%), porcentagem coincidente com o apresentado na literatura nacional e mundial. Os antimicrobianos para esse uropatógeno com maior resistência foram ampicilina (86%), cirprofloxacina (55%) e norfloxacina (53%). Poderia ser tido em conta no momento de administrar uma terapêutica empírica, dado que deveria ser corroborado com informação de suscetibilidades de acordo com o contexto.


Assuntos
Humanos , Feminino , Farmacorresistência Bacteriana , Infecções Urinárias , Equador , Escherichia coli Uropatogênica
7.
J. health inform ; 8(supl.I): 327-340, 2016. ilus, tab, graf
Artigo em Português | LILACS | ID: biblio-906285

RESUMO

Os avanços das tecnologias de informação e comunicação proporcionam as condições para formar uma infraestrutura para distribuição de imagens médicas em larga escala. Entretanto, mesmo considerando a grande base instalada PACS/DICOM, não se observa a formação de uma infraestrutura comum para troca de imagens médicas entre entidades de saúde. OBJETIVO: Propor o DicomFlow, uma infraestrutura assíncrona, assimétrica e descentralizada para distribuição de imagens médicas, construída sobre a base instalada. MÉTODO: Especificou-se um protocolo para troca de mensagens e transmissão de imagens médicas e construiu-se um modelo arquitetural em duas camadas. RESULTADO: Três experimentos foram realizados para avaliar preliminarmente a infraestrutura quanto a sua viabilidade técnica e operacional.CONCLUSÃO: O DicomFlow possibilita a troca de imagens entre profissionais e organizações de saúde quaisquer,desde que pertençam à base instalada, fomentando a formação de uma infraestrutura de informação para distribuição de imagens médicas.


Advances in information and communication technologies have provided the conditions for the formation ofan infrastructure for medical images distribution on a large scale. However, even considering the large PACS/DICO Minstalled base, it is not observed the formation of a common infrastructure for the exchange of medical images between health organizations. OBJECTIVE: To propose DicomFlow, an asynchronous, asymmetric, and decentralized infrastructure for distribution of medical images, built on the installed base. METHOD: A protocol for messaging and transmission of medical images was specified and an architectural model in two layers was built. RESULTS: Three experiments we recarried out to evaluate preliminarily the proposed infrastructure with respect to its technical and operational feasibility. CONCLUSION: DicomFlow enables the exchange of images between any health professionals and organizations, provided that they belong to the installed base, fostering the emergence of an information infrastructure for distribution of medical images.


Assuntos
Humanos , Informática Médica , Integração de Sistemas , Telerradiologia , Congressos como Assunto
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