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Pseudomonas aeruginosa, the most prevalent opportunistic pathogen in chronic obstructive pulmonary disease, associated with high morbidity and mortality in patients with cystic fibrosis (CF), is practically impossible to be eradicated from the airways in chronicity. Its extraordinary genomic plasticity is possibly associated with high antimicrobial resistance, virulence factors, and its phenotypic diversity. The occurrence of P. aeruginosa isolates promoting airway infection, showing mucoid, non-mucoid, and small colony variant (SCV) phenotypes, was observed simultaneously, in the present study, in sputum cultures obtained from a male CF young patient with chronic pulmonary infection for over a decade. The isolates belonged to a new ST (2744) were obtained in two moments of exacerbation of the respiratory disease, in which he was hospitalized. Genetic background and phenotypic analysis indicated that the isolates exhibited multi- and pan-antimicrobial resistant profiles, as well as non-susceptible to polymyxin and predominantly hypermutable (HPM) phenotypes. Whole genome sequencing showed variations in genome sizes, coding sequences and their determinants of resistance and virulence. The annotated genomes were compared for antimicrobial resistance, hypermutability, and SCV characteristics. We highlight the lack of reported genetic determinants of SCV emergence and HPM phenotypes, which can be explained in part due to the very short time between collections of isolates. To the best of our knowledge, this is the first report of genome sequencing of P. aeruginosa SCV from a CF patient in Brazil. [ABSTRACT FROM AUTHOR]

Cellulose nanowhiskers (CNWs) were incorporated into a superabsorbent hydrogel of starch grafted with poly(acrylic acid) (ST-g-PAAc) to obtain adsorbent materials with superior performance for Pb(II) removal from water. Herein, various experimental and theoretical analyses were conducted to highlight and elucidate the contribution of CNWs to the adsorption process. The presence of 10 wt% CNWs in the hydrogel led to an approximately 12% increase in the adsorption capacity of Pb(II) compared to the hydrogel without CNWs. Indeed, 25 mg of composite hydrogel required a short contact time (60 min) to achieve high adsorption capacities (935.8 mg/g). It was demonstrated that CNWs in the composite matrix also mitigate the effects of temperature and competition with other ions, enhancing the stability, selectivity, and efficiency of the Pb(II) adsorption. Density functional theory (DFT) calculations revealed that the hydroxyl groups of CNWs play a crucial role by providing additional binding energies (30 kcal/mol) for Pb(II) ions, favoring the spontaneity and kinetics of the adsorption process. Kinetic and isothermal investigations revealed that the adsorption process on the CNW-containing hydrogel involves chemisorption and intra-particle diffusion, indicating multiple steps during the adsorption of Pb(II) ions. Furthermore, the CNW-containing hydrogel demonstrated excellent reusability, with only an 8% loss in adsorption capacity after six consecutive reuses. This characteristic makes the composite hydrogel highly attractive for practical applications in real-world scenarios. In summary, the experimental and theoretical data collected in this study confirm the superior adsorption performance of the composite hydrogel due to the presence of CNWs. [ABSTRACT FROM AUTHOR]

Furanic compounds such as 5-hydroxymethylfurfural (HMF) and furfural (FF) obtained from biomass have emerged as important industrial chemical platforms. In this sense, the present study aimed to evaluate the economical use of crude biomass of rice husk (RH), cupuaçu peel (CP), and pequi peel (PP) to obtain furanic compounds such as HMF and FF, using the ionic liquid 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]) and the catalyst chromium(III) chloride hexahydrate (CrCl3.6H2O). The results of the analysis showed that biomasses have potential for use in biorefineries; however, the most promising among those is the RH, due to the significant content of holocellulose. The optimization of hydrolysis through the methodology developed by Dunning and Dallas (1949) made it possible to obtain significant levels of glucose (14.28%), xylose (3.81%), and arabinose (0.93%). The obtained products were analyzed by Fourier transform infrared spectrophotometry (FT-IR) and high-performance liquid chromatography (HPLC). The best yields for RH obtained were 1.92% (HMF) and 2.89% (FF). From the results obtained, it can be concluded that the RH has a good capacity for producing value-added compounds in biorefineries. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is associated with chronic and progressive lung disease and is closely related to increased morbidity and mortality in cystic fibrosis (CF) patients. Hypermutable (HPM) P. aeruginosa isolates have been described in these patients and are usually associated with antibiotic resistance. This study aimed to investigate the occurrence of carbapenem resistance and hypermutable phenotype in 179 P. aeruginosa isolates from 8 chronically CF patients assisted at two reference centers in Rio de Janeiro, Brazil. Using disk diffusion test, non-susceptible (NS) rates higher than 40% were observed for imipenem, amikacin, and gentamicin. A total of 79 isolates (44.1%), 71 (39.6%), and 8 (4.4%) were classified as carbapenem-resistant (CR resistance to at least one carbapenem), multidrug-resistant (MDR), and extensively drug-resistant (XDR), respectively. Minimal inhibitory concentration was determined for 79 CR P. aeruginosa and showed the following variations: 4 and 128 μg/mL to imipenem, 4 and 64 µg/mL to meropenem, and 4 and ≥ 32 µg/mL to doripenem. We have found only four (2.23%) HPM isolates from 4 patients. Analyzing the genetic relationship among the HPM isolates, 3 pulsed-field gel electrophoresis/pulsotypes (D, M, and J) were observed. Only M pulsotype was recovered from two patients in different years. Polymerase chain reaction screening for blaGES, blaIMP, blaKPC, blaNDM, blaOXA-48, blaSPM, and blaVIM genes was performed for all CR isolates and none of them were positive. Our results demonstrate a high occurrence of CR and MDR P. aeruginosa of CF patients follow-up in both centers studied, while the presence of HPM is still unusual. [ABSTRACT FROM AUTHOR]

Objective: This in situ study evaluated the effect of high-fluoride dentifrice (5000 μg F−/g) and fluoride-containing bonding composite resin on enamel demineralization adjacent to orthodontic brackets. Methods: Ten volunteers wore palatal appliances containing bovine enamel blocks with metallic brackets bonded with fluoride-free or fluoride-containing composite resin. During three phases of 14 days each, three dentifrices with different fluoride concentrations (0, 1100, and 5000 μg F−/g) were tested. The cariogenic challenge consisted of 20% sucrose solution dripped 8x/day onto the dental blocks. At the end of each phase, biofilm formed was collected for fluoride analysis. Cross section hardness was performed in enamel blocks, and the lesion area was calculated. Data were analyzed by two-way ANOVA followed by Tukey post hoc test (α = 5%). Results: The only signicant factor for all the variables under study was the dentifrice. Smaller lesion area and higher fluoride concentration on biofilm were found in 5000 μg F−/g group, irrespective of bonding composite resin (p < 0.001). Neither bracket-bonding composite resin nor the interaction between the factors was statistically significant (p > 0.05) for all the variables. Conclusion: High-fluoride dentifrice is effective in reducing demineralization on enamel adjacent to orthodontic brackets, while the fluoride-containing bonding composite resin does not influence it. Clinical Significance: Since high-fluoride dentifrice was able to reduce demineralization adjacent to brackets, it can be an option to caries management in orthodontics patients. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) is one of the most popular and widely used oxidants. Among the wide range of synthesis techniques used for the production of H2O2; the electrochemical method allows the use of gas diffusion electrodes to generate H2O2 without limiting the low solubility of O2 in water. The present work reports the modification of carbon black with quinone, where the generation of H2O2 occurs in an electrochemical/chemical mechanism. The results obtained by this technique were found to be highly promising. The use of the organic compound 1,2-dihydroxyanthraquinone to modify carbon black electrode resulted in greater production of H2O2. Carbon black electrode modified with 1% of 1,2-dihydroxyanthraquinone yielded 298 mg L−1 of H2O2 at the end of 90 min of experiment, reaching an electrical efficiency of approximately 25.5%. Based on the findings of this study, H2O2 generation is found to be directly associated with the chemical structure of the carbon modifier and not solely related to the presence of quinone groups. [ABSTRACT FROM AUTHOR]

Oxidative stress plays an important role in the evolution of aging and life history. High investments in life-history traits and environmental conditions can be associated with increased oxidative stress and aging process. However, to date, most studies that investigated variations in oxidative status were performed with long-lived vertebrates. Studies with short-lived vertebrates in wild are nonexistent. Annual killifishes have the shortest lifespans among vertebrates and inhabit temporary ponds subject to large variations in environmental conditions. In this sense, we investigated whether the high investment in growth and reproduction in a short-lived vertebrate and the large variations in environment has any cost in susceptibility to oxidative stress. We assessed the seasonal variation and the environmental correlates of four different oxidative status markers (lipid peroxidation and activity of the antioxidant enzymes Superoxide Dismutase, Catalase and Glutathione S-Transferase) along the life cycle of wild individuals of the Neotropical annual fish Austrolebias minuano. Males showed reduction in all biomarkers (except proteins) along their life cycle, while females showed increased oxidative stress only in the growth period. In addition, we showed that water physicochemical parameters, habitat structure and presence of co-occurring killifish species influenced the seasonal variation of the biomarkers. A. minuano showed an efficient antioxidant system for most part of their life cycle (mainly in males), suggesting a well-developed oxidative stress regulation system. We also show that annual fish mortality (mainly in males) apparently is not related to oxidative stress. Thus, environmental factors should drive annual fish aging and mortality. [ABSTRACT FROM AUTHOR]

Prolonged exposure to hyperoxia has deleterious effects on the lung, provoking both inflammation and alveolar injury. The elements of hyperoxic injury, which result in high rates of lethality in experimental models, are thought to include multicellular immune responses. To characterize these alterations in immune cell populations, we performed time-of-flight mass cytometry (CyTOF) analysis of CD45-expressing immune cells in whole lung parenchyma and the bronchoalveolar space of mice, exposed to 48 hours of hyperoxia together with normoxic controls. At the tested time point, hyperoxia exposure resulted in decreased abundance of immunoregulatory populations (regulatory B cells, myeloid regulatory cells) in lung parenchyma and markedly decreased proliferation rates of myeloid regulatory cells, monocytes and alveolar macrophages. Additionally, hyperoxia caused a shift in the phenotype of alveolar macrophages, increasing proportion of cells with elevated CD68, CD44, CD11c, PD-L1, and CD205 expression levels. These changes occurred in the absence of histologically evident alveolar damage and abundance of neutrophils in the parenchyma or alveolar space did not change at these time points. Collectively, these findings demonstrate that pulmonary response to hyperoxia involves marked changes in specific subsets of myeloid and lymphoid populations. These findings have important implications for therapeutic targeting in acute lung injury. [ABSTRACT FROM AUTHOR]

Aging processes have become an attractive field for researchers and annual fish have been used as biological models. However, the study on the changes in age-associated markers during the normal aging in wild populations of annual fish remains open. Austrolebias is a genus of Neotropical annual killifishes, distributed mainly in ephemeral pools across grassland floodplains of temperate South America and represent an emerging biological model for aging research, but studies investigating rapid aging and senescence in this genus of annual fish are almost non-existent. This study was undertaken to examine the changes in age-associated liver markers at the different developmental stages in wild populations of Austrolebias minuano. We demonstrate that A. minuano has a number of liver alterations of different severities throughout the life cycle, suggesting that these changes tend to increase with age. Our results revealed that > 70% of the analyzed livers presented alterations. Thus, our study should instigate new approaches on aging using Neotropical annual fish, and could be useful to improve the knowledge already provided by consecrated biological aging models as e.g. Nothobranchius killifishes. [ABSTRACT FROM AUTHOR]

The objective of this work was to observe the significant factors for the dehydration reaction of xylose to furfural and to optimize the processes using experimental design. The studied variables were temperature, time, initial percentage of xylose mass, and catalyst/xylose ratio. Temperature and initial percentage of xylose mass were considered statistically significant, while the maximum point for furfural selectivity was at 160 °C and 2% of initial xylose mass. Using niobic acid and niobium phosphate (1:1) (NbP/NbA), 44.05% xylose conversion and 74.71% furfural selectivity were obtained. The results showed that the mixture of catalysts with Brönsted acid and Lewis acid sites improved the selectivity of furfural from the xylose dehydration reaction. NbP/NbA catalysts were very stable under the investigated condition after 5 continuous recycles. [ABSTRACT FROM AUTHOR]

Purpose: Umbilical hernia is a common complication in patients with cirrhosis. Early studies have reported a high morbidity and mortality associated with hernia repair. The traditional approach has been to non-operatively manage umbilical hernias in patients with cirrhosis. There are emerging data suggesting that an elective repair is a preferable approach. This study examined the outcomes of umbilical hernia repair in patients with advanced liver disease and compared this with a control group of non-cirrhotic patients.Methods: Prospective data were collected regarding the outcome of umbilical hernia repairs performed between 2004 and 2013 at the Austin Hospital, Melbourne, Australia. Outcomes at 90 days were compared between patients with and without cirrhosis.Results: 79 patients with cirrhosis and 249 controls were analysed. Of the patients with cirrhosis, 9% were classified as Child-Pugh A, 61% were Child-Pugh B and 30% were Child-Pugh C. Emergency repairs for complicated hernias was undertaken in 18% of the cirrhosis population and 10% in controls (P = 0.10). Post-operative complications occurred more commonly in patients with cirrhosis (26%) compared with controls (11%) (P < 0.01). Emergency hernia repairs were associated with a higher complication rate in both patients with cirrhosis (62%) and controls (20%) (P = 0.01). There was no significant difference in the rate of hernia recurrence as assessed by clinical examination between patients with cirrhosis (2.7%) and controls (6.8%) (P = 0.17) nor in 90-day mortality between patients with cirrhosis (n = 1, 1.3%) and the controls (n = 0) (P = 0.43).Conclusions: Within the limitations of a small study cohort and therefore an underpowered study, elective surgical repair of umbilical hernias in patients with cirrhosis, including decompensated cirrhosis, may not be associated with a significant increase in mortality when compared to a control cohort. Whilst complications are higher in cirrhotic patients, there is no difference in the rate of hernia recurrence. Emergency repairs of umbilical hernias are associated with a high complication rate in cirrhotic patients. [ABSTRACT FROM AUTHOR]

5-Hydroxymethylfurfural (HMF) production from fructose was studied by using niobium phosphate as solid acid catalyst. HMF selectivity was optimized in a water-acetone system and compared to a water system. The HMF optimal selectivity for process carried out in the water-acetone system was 62.94%. When the process was performed in water, the HMF selectivity achieved 55.73%. These results were used in a large-scale simulation and economic analysis of the two processes. The higher selectivity of system water-acetone affected the HMF minimum selling price (MSP). The MSP value was 2.21 USD/kg for process performed in water-acetone and 3.05 USD/kg for process in water. In the sensitivity analysis, we have found that in addition to process selectivity, the fructose cost was the most significant factor affecting HMF price. [ABSTRACT FROM AUTHOR]

Annual fishes (AF) are ecologically unique assemblage with major conservation concern. Several AF species are found in temporary waters of South American subtropical grasslands, an ecoregion largely neglected by conservation policies. We applied a broad-scale approach to understand distribution pattern of the AF and tested the effects of environmental predictors on occurrence, abundance and assemblage structure of this diverse Neotropical group of threatened endemic aquatic fauna. We recorded 23 AF species. AF assemblage was strongly spatially structured and many individual species formed discrete units. AF presence was negatively associated with altitude at the landscape scale, and negatively associated with maximum pool depth and presence of predatory fish at the local scale. We found negative association between AF abundance and water depth. Assemblage composition was spatially structured, differed among hydrographic regions and was influenced by altitude, temperature and monthly precipitation. AF inhabits highly vulnerable habitats currently located in livestock and agricultural landscapes. Habitat maintenance through wildlife-friendly practices should be considered as an alternative to promote AF conservation. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

To evaluate whether a recombinant serine protease inhibitor (rBmTI-A) modulates inflammation in an experimental model of chronic allergic lung inflammation. Balb/c mice were divided into four groups: SAL (saline), OVA (sensitized with ovalbumin), SAL + rBmTI-A (control treated with rBmTI-A) and OVA + rBmTI-A (sensitized with ovalbumin and treated with rBmTI-A). The animals received an intraperitoneal injection of saline or ovalbumin, according to the group. The groups received inhalation with saline or ovalbumin and were treated with rBmTI-A or saline by nasal instillation. After 29 days, we evaluated the respiratory mechanics; bronchoalveolar lavage fluid (BALF); cytokines; MMP-9, TIMP-1; eosinophils; collagen and elastic fibre expression in the airways; and the trypsin-like, MMP-1, and MMP-9 lung tissue proteolytic activity. Treatment with rBmTI-A reduced the trypsin-like proteolytic activity, the elastance and resistance maximum response, the polymorphonuclear cells, IL-5, IL-10, IL-13 and IL-17A in the BALF, the expression of IL-5, IL-13, IL-17, CD4+, MMP-9, TIMP-1, eosinophils, collagen and elastic fibres in the airways of the OVA + rBmTI-A group compared to the OVA group (p < 0.05). rBmTI-A attenuated bronchial hyperresponsiveness, inflammation and remodelling in this experimental model of chronic allergic pulmonary inflammation. This inhibitor may serve as a potential therapeutic tool for asthma treatment. [ABSTRACT FROM AUTHOR]