Different silicon forms sinalize an input of urbanized river and indicate the presence of phytoplankton with silicon structures in the tropical coastal area of Recife (PE-Brazil)

As áreas urbanizadas marcam sua presença nos sistemas hidrológicos com alguns sinais biogeoquímicos, incluindo entradas de silício. A influência natural da lixiviação e erosão é feita por contribuição de silicato e, às vezes, o solo agrícola possui microfilóticos e contribui com sílica biogênica. Uma vez no sistema hidrológico, o silício pode integrar os ciclos biogeoquímicos mostrando um equilíbrio ou não entre formas inorgânicas e biológicas que revela uma tendência de processos que ocorrem em cada setor da interface estuarino-marinha. Este estudo tem como objetivo avaliar o impacto de um rio fortemente poluído/urbanizado, cujo aporte pode ser evidenciado por diferentes formas de silício que podem marcar o aporte terrestre, processo de erosão, a presença de espécies de fitoplâncton com estruturas silicosas, principalmente associada a diatomáceas e, também, estudar a pluma do rio espalhando-se na área costeira realizando perfis de silício na região adjacente à foz do rio. A região costeira do Recife está sob influência dos insumos fluviais dos rios Capibaribe e Beberibe verificados pela baixa salinidade observada (mínimo 33,93). A distribuição de formas de silício mostrou variação setorial e os valores máximos foram distintos. O silicato dissolvido atingiu 14,40 µmol L-1, silício litogênico (LSi) no máximo de 25,76 µmol L-1 e sílica biogênica (BSi) atingindo 7,39 µmol L-1 perto da foz do rio em direção ao mar, evidenciando a influência do rio vindo do oeste, alcançando a barreira portuária no final e se propagando no mar em direção ao nordeste. Devido à maior disponibilidade de nutrientes nas estações mais próximas da costa, a produção primária foi incentivada com a evidência de altos valores de clorofila-a associados ao silicato dissolvido (r=0.71) e ao SiB (r=0.44). Nas estações mais distantes da costa, as formas de silício apresentaram concentrações muito baixas e BSi/Clorofila-a mostrou correlação negativa associada a concentrações de clorofila-a, evidenciando a participação de atores não silicosos na produção primária em profundidade média em águas tropicais oligotróficas.The urbanized areas mark its presence in the hydrological systems with some biogeochemical signs including silicon inputs. Natural influence of leaching and erosion is done by silicate contribution and sometimes, the agriculturally soil contains microphytoliths and contributes with biogenic silica. Once in the hydrological system, the silicon can integrate the biogeochemical cycles showing a balance or not between inorganic and biological forms that reveals a tendency of processes that occur in each sector of the estuarine-marine interface. This study aims to evaluate the impact of a heavily polluted/urbanized river, whose input can be evidenced by the contribution of different forms of silicon that can evidence the terrestrial contribution, erosion process, the presence of phytoplankton species with siliceous structures, mainly associated to diatoms and also, to study the river plume spreading on the coastal area by undertaking silicon profiles in the region adjacent to the river mouth. The coastal region of Recife is under influence of fluvial inputs from Capibaribe and Beberibe rivers verified by observed low salinity (min. 33.93). The distribution of silicon forms showed sectorial variation, and the maximum values were dissimilar. Dissolved silicate reached 14.40 µmol L-1, lithogenic silicon (LSi) maximum of 25.76 µmol L-1 and biogenic silica (BSi) reaching 7.39 µmol L-1 near the river mouth toward the sea, evidencing the river influence coming from the west, achieving the port barrier at the end and propagating in the sea toward northeast. Due to higher nutrient availability in the stations nearest to the coast, primary production was encouraged with evidencing by high values of chlorophyll-a associated to silicate (r=0.71) and to BSi (r=0.44). In the stations more distant to the coast, the forms of silicon showed very low concentrations and BSi/Chlorophyll-a showed negative correlation associated with chlorophyll-a concentrations evidencing the participation of non-silicon actors in the primary production in medium depth in oligotrophic tropical waters

Viscoelastic Properties of Rapid Prototyped Magnetic Nanocomposite Scaffolds for Osteochondral Tissue Regeneration

Poly(ϵ-caprolactone) and poly(ethylene glycol) based magnetic nanocomposite scaffolds were fabricated using fused deposition modeling and stereolithography approaches, and a hybrid scaffold was obtained by combining these additive manufacturing technologies. Viscoelastic properties in compression were investigated at 37 °C, spanning a range frequency of four decades. Results suggest that poly(ϵ-caprolactone) and poly(ethylene glycol) based scaffolds adequately reproduce viscoelastic properties of subchondral bone and articular cartilage tissues, respectively. By combining fused deposition modeling and stereolithography it is possible to manufacture a hybrid scaffold suitable for osteochondral tissue regeneration. Poly(ϵ-caprolactone) and poly(ethylene glycol) based magnetic nanocomposite scaffolds were fabricated using fused deposition modeling and stereolithography approaches, and a hybrid scaffold was obtained by combining these additive manufacturing technologies. Viscoelastic properties in compression were investigated at 37 °C, spanning a range frequency of four decades. Results suggest that poly(ϵ-caprolactone) and poly(ethylene glycol) based scaffolds adequately reproduce viscoelastic properties of subchondral bone and articular cartilage tissues, respectively. By combining fused deposition modeling and stereolithography it is possible to manufacture a hybrid scaffold suitable for osteochondral tissue regeneration

From 3D Hierarchical Scaffolds for Tissue Engineering to Advanced Hydrogel-Based and Complex Devices for in situ Cell or Drug Release☆

Abstract In the past few years, researchers have focused on the development of three-dimensional (3D) advanced scaffolds and multifunctional hydrogel-based materials. As reported in literature, 3D polymer-based composite scaffolds for tissue engineering have been manufactured through conventional and advanced manufacturing techniques, and different injectable materials and hydrogel-based systems have been proposed and studied. The aim of the current research was to define an approach in the development of multifunctional tools spanning from 3D hierarchical scaffolds for soft tissue engineering to advanced hydrogel-based devices for in situ cell or drug release. The mechanical/rheological behaviour as well as the structural/functional features of the designed devices were discussed and analyzed

Biofilm is a major virulence determinant in bacterial colonization of chronic skin ulcers independently from the multidrug resistant phenotype

Bacterial biofilm is a major factor in delayed wound healing and high levels of biofilm production have been repeatedly described in multidrug resistant organisms (MDROs). Nevertheless, a quantitative correlation between biofilm production and the profile of antimicrobial drug resistance in delayed wound healing remains to be determined. Microbial identification, antibiotic susceptibility and biofilm production were assessed in 135 clinical isolates from 87 patients. Gram-negative bacteria were the most represented microorganisms (60.8%) with MDROs accounting for 31.8% of the total isolates. Assessment of biofilm production revealed that 80% of the strains were able to form biofilm. A comparable level of biofilm production was found with both MDRO and not-MDRO with no significant differences between groups. All the methicillin-resistant Staphylococcus aureus (MRSA) and 80% of Pseudomonas aeruginosa MDR strains were found as moderate/high biofilm producers. Conversely, less than 17% of Klebsiella pneumoniae extended-spectrum beta-lactamase (ESBL), Escherichia coli-ESBL and Acinetobacter baumannii were moderate/high biofilm producers. Notably, those strains classified as non-biofilm producers, were always associated with biofilm producer bacteria in polymicrobial colonization. This study shows that biofilm producers were present in all chronic skin ulcers, suggesting that biofilm represents a key virulence determinant in promoting bacterial persistence and chronicity of ulcerative lesions independently from the MDRO phenotype

Intervention of Occupational Therapy in patient with Stroke in acute phase: Systematic Review

Objective: The objective of this work was both to fill this gap in the scientific literature, and to evaluate the results of an Occupational Therapy treatment in individuals affected by an acute phase stroke, taking into account Randomized Controlled Trial (RCT). Methods: A systematic review was carried out according to PRISMA guidelines. Three bibliographic databases were searched, namely MEDLINE, CINAHL and PEDro. The minimal prerequisites included in existing papers on such systematic reviews were: (a) Randomized Controlled Trial, (b) published in English (c) during the last ten years (2006 -2016). Studies were evaluated according to Jadad Score. Results: 12 studies were included. Selected papers showed an average Jadad score of 2,15. Conclusions: The review suggests that so far there is not a more effective treatment in comparison to others; moreover, available studies lack available samples and overall show to have a poor Jadad score. Nevertheless, a number of suggestive results emerged by the study carried out. Occupational therapists shall perform and report higher quality clinical studies as well as an increased evidence level with the aim to build up a trustworthy arsenal of evidence-based interventions for people with acute stroke

DECLINE OF PREVALENCE OF RESISTANCE ASSOCIATED SUBSTITUTIONS TO NS3 AND NS5A INHIBITORS AT DAA- FAILURE IN HEPATITIS C VIRUS IN ITALY OVER THE YEARS 2015 TO 2018

Background: A minority of patients fails to eliminate HCV and resistance-associated substitutions (RASs) are commonly detected at failure of interferon-free DAA regimens . Methods: Within the Italian network VIRONET-C, the prevalence of NS3/NS5A/NS5B RASs was retrospectively evaluated in patients who failed an EASL recommended DAA-regimen in 2015-2018 . The geno2pheno system and Sorbo MC et al. Drug Resistance Updates 2018 were used to infer HCV- genotype/subtype and predict drug resistance . The changes in prevalence of RASs over time were evaluated by chi-square test for trend, predictors of RASs at failure were analysed by logistic regression . Results: We included 386 HCV infected patients: 75% males, median age was 56 years (IQR 52-61), metavir fibrosis stage F4 in 76%; 106 (28%) were treatment- experienced: 91 (86%) with IFN-based treatments, 26 (25%) with DAAs. Patients with HIV and HBV coinfection were 10% (33/317) and 8% (6/72), respectively. HCV genotype was 1b in 122 pts (32%), 3 in 109 (28%), 1a in 97 (25%), 4 in 37 (10%), 2 in 21 (5%). DAA regimens were: LDV/SOF in 115 (30%), DCV/SOF in 103 (27%), 3D in 83 (21%), EBR/GRZ in 32 (8%), VEL/SOF in 29 (7%), GLE/PIB in 18 (5%) and 2D in 6 (2%); ribavirin was administered in 123 (32%) . The NS5A fasta-sequence was available for all patients, NS5B for 361 (94%), NS3 for 365 (95%) . According to the DAA failed the prevalence of any RASs was 90%, namely 80/135 (59%) in NS3, 313/359 (87%) in NS5A, 114/286 (40%) in NS5B . The prevalence of any RASs significantly declined from 2015 to 2018 (93% vs 70%, p=0.004): NS5A RASs from 90% to 72% (p=0 .29), NS3 RASs from 74% to 18% (p<0 .001), while NS5B RASs remained stable . Independent predictors of any RASs included advanced fibrosis (AOR 6.1, CI 95% 1.8-20.3, p=0 .004) and genotype (G2 vs G1a AOR 0 .03, CI 95% 0 .002- 0 .31, p=0 .004; G3 vs G1a AOR 0 .08, CI 95% 0 .01-0 .62, p=0 .02; G4 vs G1a AOR 0 .05, CI 95% 0 .006-0 .46, p=0 .008), after adjusting for age, previous HCV treatment and year of genotype . Notably, full activity was predicted for GLE/PIB in 75% of cases and for at least two components of VEL/SOF/VOX in 53% of cases, no case with full-resistance to either regimen was found . Conclusion: Despite decreasing prevalence over the years, RASs remain common at virological failure of DAA treatment, particularly in patients with the highest grade of liver fibrosis. The identification of RASs after failure could play a crucial role in optimizing retreatment strategies

Natural Variation of Model Mutant Phenotypes in Ciona intestinalis

BACKGROUND: The study of ascidians (Chordata, Tunicata) has made a considerable contribution to our understanding of the origin and evolution of basal chordates. To provide further information to support forward genetics in Ciona intestinalis, we used a combination of natural variation and neutral population genetics as an approach for the systematic identification of new mutations. In addition to the significance of developmental variation for phenotype-driven studies, this approach can encompass important implications in evolutionary and population biology. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report a preliminary survey for naturally occurring mutations in three geographically interconnected populations of C. intestinalis. The influence of historical, geographical and environmental factors on the distribution of abnormal phenotypes was assessed by means of 12 microsatellites. We identified 37 possible mutant loci with stereotyped defects in embryonic development that segregate in a way typical of recessive alleles. Local populations were found to differ in genetic organization and frequency distribution of phenotypic classes. CONCLUSIONS/SIGNIFICANCE: Natural genetic polymorphism of C. intestinalis constitutes a valuable source of phenotypes for studying embryonic development in ascidians. Correlating genetic structure and the occurrence of abnormal phenotypes is a crucial focus for understanding the selective forces that shape natural finite populations, and may provide insights of great importance into the evolutionary mechanisms that generate animal diversity