Infected pancreatic necrosis: outcomes and clinical predictors of mortality. A post hoc analysis of the MANCTRA-1 international study

: The identification of high-risk patients in the early stages of infected pancreatic necrosis (IPN) is critical, because it could help the clinicians to adopt more effective management strategies. We conducted a post hoc analysis of the MANCTRA-1 international study to assess the association between clinical risk factors and mortality among adult patients with IPN. Univariable and multivariable logistic regression models were used to identify prognostic factors of mortality. We identified 247 consecutive patients with IPN hospitalised between January 2019 and December 2020. History of uncontrolled arterial hypertension (p = 0.032; 95% CI 1.135-15.882; aOR 4.245), qSOFA (p = 0.005; 95% CI 1.359-5.879; aOR 2.828), renal failure (p = 0.022; 95% CI 1.138-5.442; aOR 2.489), and haemodynamic failure (p = 0.018; 95% CI 1.184-5.978; aOR 2.661), were identified as independent predictors of mortality in IPN patients. Cholangitis (p = 0.003; 95% CI 1.598-9.930; aOR 3.983), abdominal compartment syndrome (p = 0.032; 95% CI 1.090-6.967; aOR 2.735), and gastrointestinal/intra-abdominal bleeding (p = 0.009; 95% CI 1.286-5.712; aOR 2.710) were independently associated with the risk of mortality. Upfront open surgical necrosectomy was strongly associated with the risk of mortality (p < 0.001; 95% CI 1.912-7.442; aOR 3.772), whereas endoscopic drainage of pancreatic necrosis (p = 0.018; 95% CI 0.138-0.834; aOR 0.339) and enteral nutrition (p = 0.003; 95% CI 0.143-0.716; aOR 0.320) were found as protective factors. Organ failure, acute cholangitis, and upfront open surgical necrosectomy were the most significant predictors of mortality. Our study confirmed that, even in a subgroup of particularly ill patients such as those with IPN, upfront open surgery should be avoided as much as possible. Study protocol registered in ClinicalTrials.Gov (I.D. Number NCT04747990)

Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial

Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt

Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation

Papel do receptor de PAF na infecção experimental pelo vírus influenza A

Exportado OPUSMade available in DSpace on 2019-08-13T21:31:53Z (GMT). No. of bitstreams: 1 disserta__o_corrigida_p_s_defesa_13_12_10.pdf: 45652382 bytes, checksum: 9790c77f73f62db51312ea2a6360af2f (MD5) Previous issue date: 5A gripe é uma doença respiratória de grande relevância mundial, por causar grande número de mortes e internações durante as epidemias e pandemias. Estratégias para o combate ao vírus Influenza enfrentam desafios, como o surgimento de linhagens resistentes a vacinas e antivirais. Sabe-se que respostas inflamatórias exacerbadas ao vírus são causas da grande morbidade associada à infecção. O Fator de Ativação Plaquetária PAF é um mediador fosfolipídico com efeitos diretos em respostas inflamatórias, como transmigração e ativação leucocitária. O presente estudo avaliou o papel do receptor de PAF na infecção pelos subtipos do vírus Influenza H1N1 e H3N1. Para isso, foi padronizado um modelo de infecção murina com dois inóculos do vírus H1N1, 104 e 106 PFU e com o inóculo de 106 PFU do vírus H3N1. Camundongos PAFR KO e WT foram infectados pelos dois tipos de vírus e monitorados quanto à perda de peso e letalidade por 21 dias. Animais infectados pelo vírus H1N1 foram sacrificados no 5° ou 8° dia de infecção para monitoramento do recrutamento e ativação leucocitária, produção de citocinas e quimiocinas, carga viral, sobrevida celular e lesão tecidual. O antagonista do receptor de PAF, PCA 4248, também foi utilizado durante a infecção pelo vírus H1N1 e avaliação de letalidade, perda de peso e parâmetros inflamatórios. Os resultados mostraram que o desenvolvimento dos sinais associados à doença é progressivo e dependente do inóculo e subtipo viral utilizados. O vírus H1N1, mais patogênico, provocou um intenso infiltrado neutrofílico nas vias aéreas e pulmões, edema pulmonar, lesão tecidual e grande produção de citocinas pró-inflamatórias. Animais PAFR KO foram protegidos da letalidade e perda de peso causados pelo vírus H1N1 e H3N1, em relação ao grupo WT. O antagonista PCA conferiu proteção semelhante contra H1N1 à encontrada em animais PAFR KO. A proteção esteve relacionada à redução no recrutamento de neutrófilos para as vias aéreas, no extravasamento protéico e danos pulmonares. Nos animais PAFR KO houve ainda, aumento de células NK e NKT, mas menor produção de citocinas relacionadas à ativação destas células; menor desativação de fagócitos, níveis elevados de apoptose no pulmão, carga viral igual ou menor. A ausência de PAFR manteve a resposta adaptativa à reinfecção. Conclui-se que PAFR possui, então, papel fundamental na patogênese da gripe e pode representar um alvo terapêutico para a contenção da inflamação associada à infecção.Flu is a respiratory illness of great global relevance, as it causes large number of hospitalizations and deaths during epidemics and pandemics. Strategies to combat the Influenza virus face challenges such as the emergence of strains resistant to vaccines and antiviral drugs. It is known that exacerbated inflammatory responses to the virus are causes of morbidity associated with infection. The Platelet Activation Factor PAF is a phospholipid mediator with direct effects on inflammatory responses such as leukocyte activation and transmigration. This study evaluated the role of PAF receptor during infection by H1N1 and H3N1 influenza virus subtypes. To this purpose, a murine model of infection was determined with two inocula of H1N1 virus, 104 and 106 PFU and the inoculum of 106 PFU of the virus H3N1. PAFR KO and WT mice were infected by the two subtypes of virus and had weight loss and lethality monitored for 21 days. Animals infected with H1N1 virus were sacrificed at 5 or 8 days of infection to verify the recruitment and leukocyte activation, production of cytokines and chemokines, viral load, cell survival and tissue injury. The PAF receptor antagonist, PCA 4248, was also used during H1N1 virus infection and evaluation of lethality, weight loss and inflammatory parameters. The results showed that the development of the signs associated with the disease is progressive and dependent on the inoculum and viral strain used. The H1N1 virus, more pathogenic, caused an intense neutrophilic infiltrate into the airways and lungs, pulmonary edema, tissue injury and high production of proinflammatory cytokines. PAFR KO animals were protected from lethality and weight loss caused by H1N1 and H3N1 viruses compared to WT. The PAFR antagonist PCA provided similar protection to the PAFR KO mice against H1N1 infection. The protection was related to the reduction in neutrophils recruitment to the airways, in protein leakage and lung damage. There was also an increase in NK and NKT cells, but lower production of cytokines related to activation of the same, less deactivation of phagocytes, higher levels of apoptosis in the lungs, similar or greater viral clearance. The absence of PAFR kept the adaptive response to reinfection. Thus we conclude that PAFR has a crucial role in the pathogenesis of influenza and may represent a therapeutic target to control inflammation associated with infection

IL-33 induces antigen-specific IL-5⁺ T cells and promotes allergic-induced airway inflammation independent of IL-4

Type 2 cytokines (IL-4, IL-5, and IL-13) play a pivotal role in helminthic infection and allergic disorders. CD4+ T cells which produce type 2 cytokines can be generated via IL-4-dependent and -independent pathways. Although the IL-4-dependent pathway is well documented, factors that drive IL-4-independent Th2 cell differentiation remain obscure. We report here that the new cytokine IL-33, in the presence of Ag, polarizes murine and human naive CD4+ T cells into a population of T cells which produce mainly IL-5 but not IL-4. This polarization requires IL-1R-related molecule and MyD88 but not IL-4 or STAT6. The IL-33-induced T cell differentiation is also dependent on the phosphorylation of MAPKs and NF-κB but not the induction of GATA3 or T-bet. In vivo, ST2−/− mice developed attenuated airway inflammation and IL-5 production in a murine model of asthma. Conversely, IL-33 administration induced the IL-5-producing T cells and exacerbated allergen-induced airway inflammation in wild-type as well as IL-4−/− mice. Finally, adoptive transfer of IL-33-polarized IL-5+IL-4−T cells triggered airway inflammation in naive IL-4−/− mice. Thus, we demonstrate here that, in the presence of Ag, IL-33 induces IL-5-producing T cells and promotes airway inflammation independent of IL-4

Safety and immunogenicity of influenza A(H3N2) component vaccine in juvenile systemic lupus erythematosus

Abstract Introduction Seasonal influenza A (H3N2) virus is an important cause of morbidity and mortality in the last 50 years in population that is greater than the impact of H1N1. Data assessing immunogenicity and safety of this virus component in juvenile systemic lupus erythematosus (JSLE) is lacking in the literature. Objective To evaluate short-term immunogenicity and safety of influenza A/Singapore (H3N2) vaccine in JSLE. Methods 24 consecutive JSLE patients and 29 healthy controls (HC) were vaccinated with influenza A/Singapore/INFIMH-16-0019/2016(H3N2)-like virus. Influenza A (H3N2) seroprotection (SP), seroconversion (SC), geometric mean titers (GMT), factor increase in GMT (FI-GMT) titers were assessed before and 4 weeks post-vaccination. Disease activity, therapies and adverse events (AE) were also evaluated. Results JSLE patients and controls were comparable in current age [14.5 (10.1–18.3) vs. 14 (9–18.4) years, p = 0.448] and female sex [21 (87.5%) vs. 19 (65.5%), p = 0.108]. Before vaccination, JSLE and HC had comparable SP rates [22 (91.7%) vs. 25 (86.2%), p = 0.678] and GMT titers [102.3 (95% CI 75.0–139.4) vs. 109.6 (95% CI 68.2–176.2), p = 0.231]. At D30, JSLE and HC had similar immune response, since no differences were observed in SP [24 (100%) vs. 28 (96.6%), p = 1.000)], SC [4 (16.7%) vs. 9 (31.0%), p = 0.338), GMT [162.3 (132.9–198.3) vs. 208.1 (150.5–287.8), p = 0.143] and factor increase in GMT [1.6 (1.2–2.1) vs. 1.9 (1.4–2.5), p = 0.574]. SLEDAI-2K scores [2 (0–17) vs. 2 (0–17), p = 0.765] and therapies remained stable throughout the study. Further analysis of possible factors influencing vaccine immune response among JSLE patients demonstrated similar GMT between patients with SLEDAI  0.05). Conclusion This is the first study that identified adequate immune protection against H3N2-influenza strain with additional vaccine-induced increment of immune response and an adequate safety profile in JSLE. ( www.clinicaltrials.gov , NCT03540823)

Protective immunity and safety of a genetically modified influenza virus vaccine.

Recombinant influenza viruses are promising viral platforms to be used as antigen delivery vectors. To this aim, one of the most promising approaches consists of generating recombinant viruses harboring partially truncated neuraminidase (NA) segments. To date, all studies have pointed to safety and usefulness of this viral platform. However, some aspects of the inflammatory and immune responses triggered by those recombinant viruses and their safety to immunocompromised hosts remained to be elucidated. In the present study, we generated a recombinant influenza virus harboring a truncated NA segment (vNA-Δ) and evaluated the innate and inflammatory responses and the safety of this recombinant virus in wild type or knock-out (KO) mice with impaired innate (Myd88 -/-) or acquired (RAG -/-) immune responses. Infection using truncated neuraminidase influenza virus was harmless regarding lung and systemic inflammatory response in wild type mice and was highly attenuated in KO mice. We also demonstrated that vNA-Δ infection does not induce unbalanced cytokine production that strongly contributes to lung damage in infected mice. In addition, the recombinant influenza virus was able to trigger both local and systemic virus-specific humoral and CD8+ T cellular immune responses which protected immunized mice against the challenge with a lethal dose of homologous A/PR8/34 influenza virus. Taken together, our findings suggest and reinforce the safety of using NA deleted influenza viruses as antigen delivery vectors against human or veterinary pathogens

Low prevalence of influenza A strains with resistance markers in Brazil during 2017–2019 seasons

This project was supported by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Programa Estratégico de Apoio à Pesquisa em Saúde (PAPES), Fundação Oswaldo Cruz, CNPq, and Coordenação Geral de Laboratórios de Saúde Pública (CGLAB) from the Brazilian Ministry of Health.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Laboratório Central de Saúde Pública de Sergipe. Aracaju, SE, Brazil.Laboratório Central de Saúde Pública de Sergipe. Aracaju, SE, Brazil.Laboratório Central do Estado do Paraná. Curitiba, PR, Brazil.Laboratório Central do Estado do Paraná. Curitiba, PR, Brazil.Secretaria de Saúde do Estado do Espírito Santo. Laboratório de Saúde Pública do Estado do Espírito Santo. Vitória, ES, Brazil / Universidade Federal do Espírito Santo. Núcleo de Doenças Infecciosas. Vitória, ES, Brazil.Secretaria de Saúde do Estado do Espírito Santo. Laboratório de Saúde Pública do Estado do Espírito Santo. Vitória, ES, Brazil / Universidade Federal do Espírito Santo. Núcleo de Doenças Infecciosas. Vitória, ES, Brazil.Laboratório Central de Saúde Pública do Rio de Janeiro. Rio de Janeiro, RJ, Brazil.Laboratório Central de Saúde Pública do Rio de Janeiro. Rio de Janeiro, RJ, Brazil.Secretaria de Saúde do estado do Rio Grande do Sul. Laboratório Central de Saúde Pública. Porto Alegre, RS, Brazil.Secretaria de Saúde do estado do Rio Grande do Sul. Laboratório Central de Saúde Pública. Porto Alegre, RS, Brazil.Fundação Ezequiel Dias. Laboratório Central de Saúde Pública de Minas Gerais. Belo Horizonte, MG, Brazil.Fundação Ezequiel Dias. Laboratório Central de Saúde Pública de Minas Gerais. Belo Horizonte, MG, Brazil.Laboratório Central da Saúde Pública do estado da Bahia. Salvador, BA, Brazil.Laboratório Central da Saúde Pública do estado da Bahia. Salvador, BA, Brazil.Laboratório Central de Santa Catarina. Florianópolis, SC, Brazil.Laboratório Central de Santa Catarina. Florianópolis, SC, Brazil.Ministério da Saúde. Secretaria de Ciência, Tecnologia, Inovação e Insumos Estratégicos. Instituto Evandro Chagas. Ananindeua, PA. Brasil.Ministério da Saúde. Secretaria de Ciência, Tecnologia, Inovação e Insumos Estratégicos. Instituto Evandro Chagas. Ananindeua, PA. Brasil.Instituto Adolfo Lutz. Laboratório Central de Saúde Pública do Estado de São Paulo. São Paulo, SP, Brazil.Instituto Adolfo Lutz. Laboratório Central de Saúde Pública do Estado de São Paulo. São Paulo, SP, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Departamento de Imunização e Doenças Transmissíveis. Brasília, DF, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Departamento de Imunização e Doenças Transmissíveis. Brasília, DF, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.Fiocruz Fundation. Oswaldo Cruz Institute. Laboratory of Respiratory Viruses and Measles. Rio de Janeiro, RJ, Brazil.The influenza A virus (IAV) is of a major public health concern as it causes annual epidemics and has the potential to cause pandemics. At present, the neuraminidase inhibitors (NAIs) are the most widely used anti-influenza drugs, but, more recently, the drug baloxavir marboxil (BXM), a polymerase inhibitor, has also been licensed in some countries. Mutations in the viral genes that encode the antiviral targets can lead to treatment resistance. Worldwide, a low prevalence of antiviral resistant strains has been reported. Despite that, this situation can change rapidly, and resistant strain surveillance is a priority. Thus, the aim of this was to evaluate Brazilian IAVs antiviral resistance from 2017 to 2019 through the identification of viral mutations associated with reduced inhibition of the drugs and by testing the susceptibility of IAV isolates to oseltamivir (OST), the most widely used NAI drug in the country. Initially, we analyzed 282 influenza A(H1N1)pdm09 and 455 A(H3N2) genetic sequences available on GISAID. The amino acid substitution (AAS) NA:S247N was detected in one A(H1N1)pdm09 strain. We also identified NA:I222V (n = 6) and NA:N329K (n = 1) in A(H3N2) strains. In addition, we performed a molecular screening for NA:H275Y in 437 A(H1N1)pdm09 samples, by pyrosequencing, which revealed a single virus harboring this mutation. Furthermore, the determination of OST IC50 values for 222 A(H1N1)pdm09 and 83 A(H3N2) isolates revealed that all isolates presented a normal susceptibility profile to the drug. Interestingly, we detected one A(H3N2) virus presenting with PA:E119D AAS. Moreover, the majority of the IAV sequences had the M2:S31N adamantanes resistant marker. In conclusion, we show a low prevalence of Brazilian IAV strains with NAI resistance markers, in accordance with what is reported worldwide, indicating that NAIs still remain an option for the treatment of influenza infections in Brazil. However, surveillance of influenza resistance should be strengthened in the country for improving the representativeness of investigated viruses and the robustness of the analysis

Measurement of cytokines in the lung.

<p>C57BL/6 mice were inoculated with PBS (mock) or infected intranasally with 10⁵ PFU influenza PR8 virus or vNA-Δ (n = 5) and euthanized 1, 4 and 7 dpi. The induction of murine IFN-β and IFN-λ2 (A) was measured in lungs by qRT-PCR as described in Material and Methods. The levels of cytokines IFN-γ (B), TNF-α (C), IL-1β (D), IL-6 (E), IL-4 (F) and IL-10 (G) were measured in lung tissue by ELISA. <i>n</i>  =  5 for all groups at days 1 and 4, <i>n</i>  =  5, 4, 6 for mock, PR8 and vNA-Δ viruses at day 7. Data are presented as mean ± SEM. * ** and *** for p<0.05, p<0.01 and p<0.001, respectively, when compared to mock or indicated groups (one-way ANOVA, Newman-Keuls or unpaired t test (qRT-PCRs).</p