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The results are mostly consistent with past findings, with the few discrepancies probably due to our more complete experimental approach using multiple strains of the pathogen and multiple hosts. Our work supports the need to regulate non-citrus Rutaceae plant introductions into areas, like the EU and Mediterranean, that are currently free of this economically important pathogen.

The coronavirus disease 2019 (COVID-19) pandemic has put significant pressure on hospitals and in particular on intensive care units (ICU). Some patients develop acute hypoxemic respiratory failure with profound hypoxia, which likely requires invasive mechanical ventilation during prolonged periods. Corticosteroids have become a cornerstone therapy for patients with severe COVID-19, though only little data are available regarding their potential harms and benefits, especially concerning the risk of a ventilator-associated lower respiratory tract infection (VA-LRTI).

This retrospective multicenter study included patients admitted in four ICUs from Belgium and France for severe COVID-19, who required invasive mechanical ventilation (MV). We compared clinical and demographic variables between patients that received corticosteroids or not, using univariate, multivariate, and Fine and Gray analyses to identify factors influencing VA-LRTI occurrence.

From March 2020 to January 2021, 341 patients required MV for acute respiratory failure related to COVID-19, 322 of whom were included in the analysis, with 60.6% of them receiving corticosteroids. The proportion of VA-LRTI was significantly higher in the early corticosteroid group (63.1% vs. 48.8%,

= 0.011). Multivariable Fine and Gray modeling considering death and extubation as competing events revealed that the factors independently associated with VA-LRTI occurrence were male gender (adjusted sHR1.7,

= 0.0022) and corticosteroids (adjusted sHR 1.44,

= 0.022).

in our multicenter retrospective cohort of COVID-19 patients undergoing MV, early corticosteroid therapy was independently associated with VA-LRTI.

in our multicenter retrospective cohort of COVID-19 patients undergoing MV, early corticosteroid therapy was independently associated with VA-LRTI.Acinetobacter baumannii is an opportunistic human pathogen responsible for numerous severe nosocomial infections. Genome analysis on the A. baumannii clinical isolate 04117201 revealed the presence of 13 two-component signal transduction systems (TCS). Of these, we examined the putative TCS named here as StkSR. The stkR response regulator was deleted via homologous recombination and its progeny, ΔstkR, was phenotypically characterized. Antibiogram analyses of ΔstkR cells revealed a two-fold increase in resistance to the clinically relevant polymyxins, colistin and polymyxin B, compared to wildtype. PAGE-separation of silver stained purified lipooligosaccharide isolated from ΔstkR and wildtype cells ruled out the complete loss of lipooligosaccharide as the mechanism of colistin resistance identified for ΔstkR. Hydrophobicity analysis identified a phenotypical change of the bacterial cells when exposed to colistin. Transcriptional profiling revealed a significant up-regulation of the pmrCAB operon in ΔstkR compared to the parent, associating these two TCS and colistin resistance. These results reveal that there are multiple levels of regulation affecting colistin resistance; the suggested 'cross-talk' between the StkSR and PmrAB two-component systems highlights the complexity of these systems.Halophilic microorganisms are potentially capable as platforms to produce low-cost biosurfactants. However, the robustness of bioprocesses is still a challenge and, therefore, it is essential to understand the effects of microbiological culture conditions through bioreactor engineering. Based on a design of experiments (DOE) and a response surface methodology (RSM) tailored and taken from the literature, the present work focuses on the evaluation of a composite central design (CCD) under batch cultures in stirred-tank bioreactors with the halophilic bacteria Salibacterium sp. 4CTb in order to determine the operative conditions that favor mass transfer and optimize the production of a lipopeptide. The results obtained showed profiles highlighting the most favorable culture conditions, which lead to an emulsification index (E24%) higher than 70%. Moreover, through the behavior of dissolved oxygen (DO), it was possible to experimentally evaluate the higher volumetric coefficient of mass transfer in the presence of lipopeptide (kLa = 31 1/h) as a key criterion for the synthesis of the biosurfactant on further cell expansion.Colibacillosis caused by pathogenic Escherichia coli (E. coli) is one of the most serious infectious diseases, causing an extensive burden on animal husbandry and the human healthcare system. Vaccination is one of the ideal ways to prevent E. coli infection. In this work, recombinant outer membrane protein A (rOmpA), outer membrane protein C (rOmpC) and BamA (rBamA) from E. coli O78 (CVCC CAU0768) were expressed in a prokaryotic expression system with the concentration of 1-2 mg/mL after purification. Considerable immune responses could be triggered in mice that were immunized with these recombinant proteins, high antibody titers, high total IgG level and various antibody isotypes were detected in antisera after booster immunizations. Moreover, mice immunized with several recombinant proteins in combination showed a higher survival rate with the challenge of homologous strain E. coli O78 and a more significant cross-protection effect against heterologous strain E. coli O157H7 (CICC 21530) in vivo than those of immunized alone. The antisera from immunized mice showed high affinity to multiple strains of Escherichia, Shigella and Salmonella in vitro, indicating that recombinant outer membrane proteins from E. selleck inhibitor coli O78 had the potential to be developed into universal antigenic substances against not only E. coli but also a variety of Gram-negative bacteria. rOmpA was considered as the most immunogenic protein in this work and the combination of different proteins could further enhance the immune response of immunized mice, which provided the reference for the construction of novel antigens with higher efficiency.Biofertilizers are a key component of organic agriculture. Bacterial biofertilizers enhance plant growth through a variety of mechanisms, including soil compound mobilization and phosphate solubilizing bacteria (PSB), which convert insoluble phosphorus to plant-available forms. This specificity of PSB allows them to be used as biofertilizers in order to increase P availability, which is an immobile element in the soil. The objective of our study is to assess the capacity of PSB strains isolated from phosphate solid sludge to solubilize three forms of inorganic phosphates tricalcium phosphate (Ca3(PO4)2), aluminum phosphate (AlPO4), and iron phosphate (FePO4), in order to select efficient solubilization strains and use them as biofertilizers in any type of soil, either acidic or calcareous soil. Nine strains were selected and they were evaluated for their ability to dissolve phosphate in the National Botanical Research Institute's Phosphate (NBRIP) medium with each form of phosphate (Ca3(PO4)2, AlPO4, and FePO4) as the sole source of phosphorus. The phosphate solubilizing activity was assessed by the vanadate-molybdate method. All the strains tested showed significantly (p ≤ 0.05) the ability to solubilize the three different forms of phosphates, with a variation between strains, and all strains solubilized Ca3(PO4)2 more than FePO4 and AlPO4.Livestock animals, especially poultry, are a known reservoir for extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (E. coli). They may enter the pen either via positive day-old chicks or via the environment. We developed a mathematical model to illustrate the entry and dissemination of resistant bacteria in a broiler pen during one fattening period in order to investigate the effectiveness of intervention measures on this infection process. Different management measures, such as varying amounts of litter, a slow-growing breed or lower stocking densities, were tested for their effects on broiler colonization. We also calculated the impact of products that may influence the microbiota in the chicks' digestive tract, such as pre- or probiotics, feed supplements or competitive exclusion products. Our model outcomes show that a contaminated pen or positive chicks at the beginning of the fattening period can infect the entire flock. Increasing the amount of litter and decreasing the stocking density were shown to be effective in our model. Differences in the route of entry were found if the chicks are already positive, the litter quantity must be increased to at least six times the standard of 1000 g/m2, whereas, if the pen is contaminated on the first day, three times the litter quantity is sufficient. A reduced stocking density of 20 kg/m2 had a significant effect on the incidence of infection only in a previously contaminated pen. Combinations of two or three measures were effective in both scenarios; similarly, feed additives may be beneficial in reducing the growth rate of ESBL-producing E. coli. This model is a valuable tool for evaluating interventions to reduce the transmission and spread of resistant bacteria in broiler houses. However, data are still needed to optimize the model, such as growth rates or survival data of ESBL-producing E. coli in different environments.The newly isolated strain KIGAM252T was found to be facultatively anaerobic, Gram-stain-positive, spore-forming, and rod-shaped. They grew at 10-45 °C, pH 6.0-10.0, and were able to tolerate up to 6% NaCl in the growth medium. Phylogenetic analysis indicated that the KIGAM252T strain was related to the genus Metabacillus. The cell membrane fatty acid composition of strain KIGAM252T included C150 anteiso and C150 iso (25.6%) as the major fatty acids, and menaquinone 7 was the predominant isoprenoid quinone. The major polar lipids were diphosphatidylglycerol and phosphatidylglycerol. The size of the whole genome was 4.30 Mbp, and the G + C content of the DNA was 43.8%. Average nucleotide and amino acid identity and in silico DNA-DNA hybridization values were below the species delineation threshold. Pan-genomic analysis revealed that 15.8% of all genes present in strain KIGAM252T was unique to the strain. The analysis of the secondary biosynthetic pathway predicted the carotenoid synthetic gene cluster in the strain KIGAM252T. Based on these current polyphasic taxonomic data, strain KIGAM252T represents a novel species of the genus Metabacillus that produces carotenoids, for which we propose the name Metabacillus flavus sp. nov. The type of strain was KIGAM252T (=KCTC 43261T = JCM 34406T).Giant pandas feed almost exclusively on bamboo but miss lignocellulose-degrading genes. Their gut microbiome may contribute to their nutrition; however, the limited access to pandas makes experimentation difficult. In vitro incubation of dung samples is used to infer gut microbiome activity. In pandas, such tests indicated that green leaves are largely fermented to ethanol at neutral pH and yellow pith to lactate at acidic pH. Pandas may feed on either green leaves or yellow pith within the same day, and it is unclear how pH, dung sample, fermentation products and supplied bamboo relate to one another. Additionally, the gut microbiome contribution to solid bamboo digestion must be appropriately assessed. Here, gut microbiomes derived from dung samples with mixed colors were used to ferment green leaves, also by artificially adjusting the initial pH. Gut microbiomes digestion of solid lignocellulose accounted for 30-40% of the detected final fermentation products. At pH 6.5, mixed-color dung samples had the same fermentation profile as green dung samples (mainly alcohols), while adjusting the initial pH to 4.