To explore how a succession of bacteria grown on steel coupons in a marine environment can influence their corrosion process, we designed a microcosm in laboratory to evaluate corrosion kinetics and microbial diversity over 30 days. The results described a clear influence of corrosion by a succession of different bacterial groups. During the initial period, 2-7 days, a sharp increase in the rate of corrosion was detected accompanied by the presence of Alteromonadaceae, Vibrionaceae, Oceanospirillaceae, Rhodobacteraceae, Rhodospirillaceae and Flavobacteriaceae bacteria families. After 15 days, representatives of families Piscirickettsiaceae and Pseudomonadaceae were also described, accompanied by a continuous corrosion process over the coupons. After 30 days, there was a sudden change in the profile of the bacteria present on the steel coupons, with a prevalence of Halomonadaceae family species, and establishment and continuity of the corrosion process by the biofilm grown on the coupons. The results describe differences in microbial diversity over the time, highlighting certain bacterial lithotrophic species that persisted for most of the experiment, through a complex association between bacteria and metal surfaces, which can be a new starting point for development and maintenance of a favorable microenvironment to accelerate corrosion processes.

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COVID-19 has a broad spectrum of clinical manifestations, from asymptomatic or mild/moderate symptoms to severe symptoms and death. The mechanisms underlying its clinical evolution are still unclear. Upon SARS-CoV-2 infection, host factors, such as the inflammasome system, are activated by the presence of the virus inside host cells. The search for COVID-19 risk factors is of relevance for clinical management. In this study, we investigated the impact of inflammasome single-nucleotide polymorphisms (SNPs) in SARS-CoV-2-infected individuals with distinct severity profiles at clinical presentation. Patients were divided into two groups according to disease severity at clinical presentation based on the WHO Clinical Progression Scale. Group 1 included patients with mild/moderate disease ( WHO < 6 ; n = 76 ), and group 2 included patients with severe/critical COVID-19 ( WHO ≥ 6 ; n = 357 ). Inpatients with moderate to severe/critical profiles were recruited and followed-up at Hospital Center for COVID-19 Pandemic – National Institute of Infectology (INI)/FIOCRUZ, RJ, Brazil, from June 2020 to March 2021. Patients with mild disease were recruited at Oswaldo Cruz Institute (IOC)/FIOCRUZ, RJ, Brazil, in August 2020. Genotyping of 11 inflammasome SNPs was determined by real-time PCR. Protection and risk estimation were performed using unconditional logistic regression models. Significant differences in NLRP3 rs1539019 and CARD8 rs2043211 were observed between the two groups. Protection against disease severity was associated with the A/A genotype ( OR adj = 0.36 ; P = 0.032 ), allele A ( OR adj = 0.93 ; P = 0.010 ), or carrier-A ( OR adj = 0.45 ; P = 0.027 ) in the NLRP3 rs1539019 polymorphism; A/T genotype ( OR adj = 0.5 ; P = 0.045 ), allele T ( OR adj = 0.93 ; P = 0.018 ), or carrier-T ( OR adj = 0.48 ; P = 0.029 ) in the CARD8 rs2043211 polymorphism; and the A-C-G-C-C ( OR adj = 0.11 ; P = 0.018 ), A-C-G-C-G ( OR adj = 0.23 ; P = 0.003 ), C-C-G-C-C ( OR adj = 0.37 ; P = 0.021 ), and C-T-G-A-C ( OR adj = 0.04 ; P = 0.0473 ) in NLRP3 genetic haplotype variants. No significant associations were observed for the other polymorphisms. To the best of our knowledge, this is the first study demonstrating an association between CARD8 and NLRP3 inflammasome genetic variants and protection against COVID-19 severity, contributing to the discussion of the impact of inflammasomes on COVID-19 outcomes.

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Introduction Influenza A (H3N2) virus is the most important cause of seasonal influenza morbidity and mortality in the last 50 years, surpassing the impact of H1N1. Data assessing immunogenicity and safety of this virus component are lacking in systemic lupus erythematosus (SLE) and restricted to small reports with other H3N2 strains. Objective This study aims to evaluate short-term immunogenicity and safety of influenza A/Singapore (H3N2) vaccine in SLE. Methods 81 consecutive SLE patients and 81 age- and sex-matched healthy controls (HC) were vaccinated with the influenza A/Singapore/INFIMH-16-0019/2016(H3N2)-like virus. Seroprotection (SP) and seroconversion (SC) rates, geometric mean titers(GMT), and factor increase in GMT(FI-GMT) and adverse events were assessed before and 4 weeks post-vaccination. Disease activity and therapies were also evaluated. Results Before immunization, SLE and HC groups had high SP rates (89% vs 77%, p = 0.061) and elevated GMT titer with higher levels in SLE (129.1(104.1–154.1) vs 54.8(45.0–64.6), p < 0.001). Frequency of two previous years’ influenza vaccination was high and comparable in SLE and HC (89% vs 90%, p = 1.000). Four weeks post-vaccination, median GMT increased for both groups and remained higher in SLE compared to HC (239.9(189.5–290.4) vs 94.5(72.6–116.4), p < 0.0001) with a comparable FI-GMT (2.3(1.8–2.9) vs 1.9(1.5-2.3), p = 0.051). SC rates were low and comparable for both groups (16% vs 11%, respectively, p = 0.974). Disease activity scores remained stable throughout the study ( p = 1.000) and severe adverse events were not identified. Conclusion Influenza A/Singapore (H3N2) vaccine has an adequate safety profile. The distinct immunogenicity pattern from other influenza A components characterized by a remarkably high pre- and post-vaccination SP rate and high GMT levels may be associated with previous influenza A vaccination. ( www.clinicaltrials.gov , NCT03540823).