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Mayra M F Barbosa,1,2 Alex I Kanno,1 Giovana C Barazzone,1 Dunia Rodriguez,1 Violeta Pancakova,1,3 Monalisa Trentini,1 Eliana L Faquim-Mauro,4 Amanda P Freitas,4 Mariana I Khouri,5 Jessica Lobo-Silva,5 Viviane M Goncalves,1 Rocilda P F Schenkman,1 Martha M Tanizaki,1 Diana Boraschi,6– 8 Richard Malley,9 Leonardo P Farias,5 Luciana C C Leite1 1Laboratório de Desenvolvimento de Vacinas, Instituto Butantan, São Paulo, Brazil; 2Programa de Pós-Graduação Interunidades em Biotecnologia, Universidade de São Paulo, São Paulo, Brazil; 3Université Claude Bernard Lyon 1 (UCBL1), Villeurbanne, 69100, France; 4Laboratório de Imunopatologia, Instituto Butantan, São Paulo, Brazil; 5Laboratório de Biomarcadores e Inflamação, Instituto Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil; 6Istituto di Biochimica e Biologia Cellulare, Consiglio Nazionale delle Ricerche, Napoli, Italy; 7Stazione Zoologica Anton Dohrn, Napoli, Italy; 8Shenzhen Institute of Advanced Technologies (SIAT), Chinese Academy of Sciences (CAS), Shenzhen, China Division of Infectious Diseases, Boston Children’s Hospital, Boston, MA, USA; 9Division of Infectious Diseases, Boston Children’s Hospital, Boston, MA, USACorrespondence: Luciana C C LeiteLaboratório de Desenvolvimento de Vacinas, Instituto Butantan, Av. Vital Brasil, São Paulo, 1500, SP, BrazilTel +55-11-2627-9816Email luciana.leite@butantan.gov.brPurpose: The use of adjuvants can significantly strengthen a vaccine’s efficacy. We sought to explore the immunization efficacy of bacterial outer membrane vesicles (OMVs) displaying the Schistosoma mansoni antigen, SmTSP-2, through a biotin-rhizavidin coupling approach. The rationale is to exploit the nanoparticulate structure and the adjuvant properties of OMVs to induce a robust antigen-specific immune response, in light of developing new vaccines against S. mansoni.Materials and Methods: OMVs were obtained from Neisseria lactamica and conjugated with biotin. The recombinant SmTSP-2 in fusion with the biotin-binding protein rhizavidin (rRzvSmTSP-2) was produced in E. coli and coupled to biotinylated OMVs to generate an OMV complex displaying SmTSP-2 on the membrane surface (OMV:rSmTSP-2). Transmission electron microscopy (TEM) and dynamic light scattering analysis were used to determine particle charge and size. The immunogenicity of the vaccine complex was evaluated in C57BL/6 mice.Results: The rRzvSmTSP-2 protein was successfully coupled to biotinylated OMVs and purified by size-exclusion chromatography. The OMV:rSmTSP-2 nanoparticles showed an average size of 200 nm, with zeta potential around – 28 mV. Mouse Bone Marrow Dendritic Cells were activated by the nanoparticles as determined by increased expression of the co-stimulatory molecules CD40 and CD86, and the proinflammatory cytokines (TNF-α, IL-6 and IL-12) or IL-10. Splenocytes of mice immunized with OMV:rSmTSP-2 nanoparticles reacted to an in vitro challenge with SmTSP-2 with an increased production of IL-6, IL-10 and IL-17 and displayed a higher number of CD4+ and CD8+ T lymphocytes expressing IFN-γ, IL-4 and IL-2, compared to mice immunized with the antigen alone. Immunization of mice with OMV:rSmTSP-2 induced a 100-fold increase in specific anti-SmTSP-2 IgG antibody titers, as compared to the group receiving the recombinant rSmTSP-2 protein alone or even co-administered with unconjugated OMV.Conclusion: Our results demonstrate that the SmTSP-2 antigen coupled with OMVs is highly immunogenic in mice, supporting the potential effectiveness of this platform for improved antigen delivery in novel vaccine strategies.Keywords: Schistosoma mansoni, vaccine, TSP-2 antigen, outer membrane vesicles, OMV, biotin-avidin coupling, nanoparticle

The purpose of this study was to investigate the occurrence, antimicrobial resistance patterns, phenotypic and genotypic relatedness of Salmonella enterica recovered from captive wildlife host species and in the environment in Ohio, USA. A total of 319 samples including faecal ( n = 225), feed ( n = 38) and environmental ( n = 56) were collected from 32 different wild and exotic animal species in captivity and their environment in Ohio. Salmonellae were isolated using conventional culture methods and tested for antimicrobial susceptibility with the Kirby-Bauer disc diffusion method. Salmonella isolates were serotyped, and genotyping was performed using the pulsed-field gel electrophoresis ( PFGE). Salmonella was detected in 56 of 225 (24.9%) faecal samples; six of 56 (10.7%) environmental samples and six of 38 (15.8%) feed samples. Salmonella was more commonly isolated in faecal samples from giraffes (78.2%; 36/46), cranes (75%; 3/4) and raccoons (75%; 3/4). Salmonella enterica serotypes of known public health significance including S. Typhimurium (64.3%), S. Newport (32.1%) and S. Heidelberg (5.3%) were identified. While the majority of the Salmonella isolates were pan-susceptible (88.2%; 60 of 68), multidrug-resistant strains including penta-resistant type, AmStTeKmGm (8.8%; six of 68) were detected. Genotypic diversity was found among S. Typhimurium isolates. The identification of clonally related Salmonella isolates from environment and faeces suggests that indirect transmission of Salmonella among hosts via environmental contamination is an important concern to workers, visitors and other wildlife. Results of this study show the diversity of Salmonella serovars and public health implications of human exposure from wildlife reservoirs. [ABSTRACT FROM AUTHOR]

Eastern boundary upwelling systems are characterized by high productivity that often leads to subsurface hypoxia on the shelf. Mesoscale eddies are important, frequent, and persistent features of circulation in these regions, transporting physical, chemical and biological properties from shelves to the open ocean. In austral fall of 2011, during the Tara Oceans expedition, a subsurface layer (200-400m) in which the concentration of oxygen was very low (< 2 µmol kg-1 of O2) was observed in the eastern South Pacific, ~ 900 km o?shore (30° S, 81° W). Satellite altimetry combined with CTD observations associated the local oxygen anomaly with an intrathermocline, anticyclonic, mesoscale eddy with a diameter of about 150 km. The eddy contained Equatorial Sub-surface Water (ESSW) that at this latitude is normally restricted near the coast. Un-dersaturation (44%) of nitrous oxide (N2O) and nitrite accumulation (> 0.5 µM) gave evidence for denitrification in this water mass. Based on satellite altimetry, we tracked the eddy back to its region of formation on the coast of central Chile (36.1° S, 74.6 ° W). We estimate that the eddy formed in April 2010. Field studies conducted on the Chilean shelf in June 2010 provided approximate information on initial O2and N O2concentrations of "source water" in the region at the time of eddy formation. Concentrations of both O2and N2O in the oxygen minimum zone (OMZ) of the offshore eddy were lower than its surroundings or "source water" on the shelf, suggesting that these chemical species were consumed as the eddy moved offshore. Estimates of apparent oxygen utilization rates at the OMZ of the eddy ranged from 0.29 to 44 nmol L-1 d-1 and the rate of N2O consumption was 3.92 nmol L-1 d-1. Our results show that mesoscale eddies in the ESP not only transport physical properties of the ESSW from the coast to the ocean interior, but also export and transform biogeochemical properties, creating suboxic environments in the oligotrophic region of the eastern South Pacific. Suboxic water masses that are advected by eddies act as hotspots for denitrification and loss of fixed nitrogen from the system. [ABSTRACT FROM AUTHOR]

This paper examines the performance of solar photovoltaic generators on roofs of residential buildings. The primary focus is the loss of performance due to temperature increase as function of roof material and the distance from the photovoltaic (PV) generator to the roof. A heat transfer model has been developed to predict PV module temperature, and the equations of the model were solved using the Engineering Equation Solver (EES) software. The research modeling correlates the distance of the solar generator to the roof and the roofing material with the temperature variations in the PV generator. There are many models to predict PV module temperature, but this study refines the prediction by the distance from PV module to roof and the roofing material as variables. Optimal combinations of distance and materials that minimize the heating loss in the solar generator leading to increased electrical power generation. Results show an average error of 3%–4% from the temperature predicted by the model to the temperature measured under experimental conditions in Belo Horizonte, Brazil. The minimum roof-module separation required to ensure minimal PV performance loss from heating from the roof is ∼10 cm for red ceramic and cement fiber roofs. For galvanized steel, the optimal distance is between 20 cm and 30 cm. Cement fiber shows the best predicted and measured characteristics for PV-panel roof mounting among the 3-common commercial roofs evaluated in these studies. These investigations were based on roof installations and local materials in Belo Horizonte, Brazil.

Lucas Brandolt Farias,1,2 Daniel Lavinsky,1,2 Camila Zanella Benfica,1,2 Monica Oliveira da Silva,1,2 Jacó Lavisnky,1,2 Luis Henrique Canani2,3 1Department of Ophthalmology, Federal University of Rio Grande do Sul, Porto Alegre, Brazil; 2Ophthalmology Section, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil; 3Department of Endocrinology, Federal University of Rio Grande do Sul, Porto Alegre, Brazil Purpose: To evaluate choroidal thickness and volume in patients with type 2 diabetes and microalbuminuria using spectral-domain optical coherence tomography. Methods: We recruited 37 diabetic patients without diabetic retinopathy (18 normoalbuminuric and 19 microalbuminuric) and 21 healthy controls. Choroidal thickness and volume were mapped using the automated Early Treatment Diabetic Retinopathy Study grid and a topographic map of thickness was generated manually. Choroid was also measured at 10 locations under the fovea, temporally and nasally. Results: Mean choroidal thickness and volume among patients with diabetes and microalbuminuria was reduced in all locations compared to controls (P