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In this study, seven different silver nanoparticles (AgNPs) were obtained using the fungi species from the phylum Ascomycota, Aspergillus tubingensis, Aspergillus spp., Cladosporium pini-ponderosae, Fusarium proliferatum, Epicoccum nigrum, Exserohilum rostratum, and Bionectria ochroleuca, isolated from the Brazilian biodiversity, particularly from the mangrove and Caatinga biomes. The nanoparticles were coded as AgNP-AT, AgNP-Asp, AgNP-CPP, AgNP-FP, AgNP-EN, AgNP-ER, and AgNP-BO and characterized using spectrophotometry (UV-Vis), dynamic light scattering (DLS), zeta potential, transmission electron microcopy (TEM), and Fourier-transform infrared (FTIR) spectroscopy. All the AgNPs presented homogeneous size in the range from 43.4 to 120.6 nm (DLS) and from 21.8 to 35.8 nm (TEM), pH from 4.5 to 7.5, negative charge, and presence of protein coating on their surface. The antifungal activity of the AgNPs was evaluated on clinical strains of Candida albicans, and on the non-albicans species, Candida krusei, Candida glabrata, Candida parapsilosis, Candida tropicalis, and Candida guilliermondii, common in hospital infections, and against the phytopathogens Fusarium oxysporum, Fusarium phaseoli, Fusarium sacchari, Fusarium subglutinans, Fusarium verticillioides, and Curvularia lunata, which are species responsible for serious damage to agriculture production. The AgNPs were effective against the yeasts with MICs ranging from 1.25 to 40 µM and on the phytopathogens with MICs from 4 to 250 µM, indicating the promising possibility of application of these AgNPs as antifungal agents. The results indicated that the physicochemical parameters of the AgNPs, including the functional groups present on their surface, interfered with their antifungal activity. Overall, the results indicate that there is no specificity of the AgNPs for the yeasts or for the phytopathogens, which can be an advantage, increasing the possibility of application in different areas.

RESUMO

In this study, seven different silver nanoparticles (AgNPs) were obtained using the fungi species from the phylum Ascomycota, Aspergillus tubingensis, Aspergillus spp., Cladosporium pini-ponderosae, Fusarium proliferatum, Epicoccum nigrum, Exserohilum rostratum, and Bionectria ochroleuca, isolated from the Brazilian biodiversity, particularly from the mangrove and Caatinga biomes. The nanoparticles were coded as AgNP-AT, AgNP-Asp, AgNP-CPP, AgNP-FP, AgNP-EN, AgNP-ER, and AgNP-BO and characterized using spectrophotometry (UV-Vis), dynamic light scattering (DLS), zeta potential, transmission electron microcopy (TEM), and Fourier-transform infrared (FTIR) spectroscopy. All the AgNPs presented homogeneous size in the range from 43.4 to 120.6 nm (DLS) and from 21.8 to 35.8 nm (TEM), pH from 4.5 to 7.5, negative charge, and presence of protein coating on their surface. The antifungal activity of the AgNPs was evaluated on clinical strains of Candida albicans, and on the non-albicans species, Candida krusei, Candida glabrata, Candida parapsilosis, Candida tropicalis, and Candida guilliermondii, common in hospital infections, and against the phytopathogens Fusarium oxysporum, Fusarium phaseoli, Fusarium sacchari, Fusarium subglutinans, Fusarium verticillioides, and Curvularia lunata, which are species responsible for serious damage to agriculture production. The AgNPs were effective against the yeasts with MICs ranging from 1.25 to 40 µM and on the phytopathogens with MICs from 4 to 250 µM, indicating the promising possibility of application of these AgNPs as antifungal agents. The results indicated that the physicochemical parameters of the AgNPs, including the functional groups present on their surface, interfered with their antifungal activity. Overall, the results indicate that there is no specificity of the AgNPs for the yeasts or for the phytopathogens, which can be an advantage, increasing the possibility of application in different areas.

RESUMO

Crossbreeding has been used to improve performance in beef cattle, however the effects of breed composition on methane (CH4) production, yield and intensity from cattle raised in tropical intensive and integrated systems remain unknown. To assess the impact of breed composition on performance and methane emissions, Nellore (NEL; yr 1: BW = 171.5 ± 19.4 kg; n = 10; yr 2: BW = 215.8 ± 32.3 kg, n = 25) and Angus x Nellore crossbred (AN; yr 1: BW = 214.2 ± 26.4 kg, n = 10; yr 2: BW = 242.5 ± 32.2 kg, n = 25) were compared. The animals grazed on integrated crop-livestock system in the growing phase (stocking rate 2452 kg BW/ha, herbage mass 4,884 kg dry matter (DM)/ha, forage allowance 5.9 kg DM/100kg BW) and then were finished in a feedlot. Steers (n = 8) from each breed composition were randomly selected in each phase to measure CH4 production using a sulfur hexafluoride (SF6) tracer technique and DM intake (DMI) using titanium dioxide. Compared with NEL, AN had both superior total gain and average daily gain (ADG) in the grazing period. The AN presented greater ADG in the feedlot with a shorter finishing period and resulted in greater carcass yield and carcass ADG. Methane production (kg/period) was lower in NEL (19% less) than AN in grazing (P<0.01), and no difference was observed in feedlot. The NEL had less CH4 intensity (CH4/BW) in grazing but greater CH4 per unit of ADG in the feedlot compared to AN. Breed composition did not influence the CH4 yield (CH4/DMI) in either phase, despite the difference in feedlot DMI (kg/day). In conclusion, crossbreeding may be an option to improve performance and reduce the CH4 per ADG in tropical climate conditions, resulting in lower methane emission per kg of meat produced.

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Objetivo: este estudo avaliou a resistência à fratura de facetas confeccionadas sobre dois tipos de preparo. Métodos: utilizando-se dentes bovinos, dois grupos foram preparados: grupo I (redução incisal de 1 mm) e grupo II (redução incisal de 3 mm). Facetas laminadas foram enceradas sobre preparos dentais e confeccionadas em cerâmica IPS e.max (Ivoclar Vivadent). As superfícies internas das facetas foram tratadas com ácido fluorídrico a 10% durante 20 segundos e silanizadas. A superfície preparada do dente foi condicionada durante 15 segundos com ácido fosfórico a 37%, lavada abundantemente e secada levemente. O adesivo foi aplicado em duas camadas: dente e lado interno do laminado. A cimentação foi realizada com cimento resinoso fotopolimerizável sob pressão digital, e uma máquina de teste tipo pendular foi utilizada para simular o impacto no corpo-de-prova. Resultados: os dados de energia absorvida na fratura pelas facetas laminadas foram submetidos ao teste t de Student para amostras independentes (α = 5%), que demonstrou não haver diferença significativa entre os grupos com redução incisal de 1 mm e redução incisal de 3 mm (p=0,724). Observou-se, no grupo I, 10% das facetas laminadas com perda total, 30% extensa, mas parcial, e 60% parcial. Já no grupo II, 0% das facetas laminadas com perda total, 10% extensa, mas parcial, e 90% parcial. Conclusão: embora não tenha sido demonstradas diferenças na energia absorvida entre os dois tipos de preparo, o modo de fratura nos preparos com redução incisal de 3 mm foi mais favorável.

Objective: to evaluate the fracture resistance of laminate veneers on two preparation types. Methods: two groups were made based on bovine teeth: group I (1 mm incisal reduction) and group II (3 mm incisal reduction). All Laminate veneers were waxed over tooth preparations and fabricated with the IPS e.max ceramic (Ivoclar Vivadent). Their inner surfaces were treated with 10% hydrofluoric acid for 20 seconds and received a silane agent. The tooth surface was conditioned with 37% phosphoric acid, washed, and slightly dried. The adhesive was applied at the tooth and the laminate veneer. A photo-cured luting agent was used under fi nger pressure, and the samples were placed in an impact machine test. The fracture energy data was submitted to the Student´s t test for independent samples (5% significance level). Results: no statistical difference was observed (p = 0.724). At group I, 10% of the laminates demonstrated complete loss, 30% extensive but partial loss, and 60% partial loss. For group II, the figures were 0% for complete loss, 10% extensive but partial, and 90% partial. Conclusion: although no diff erences were seen for the absorbed energy, the 3 mm incisal reduction design was the most favorable.

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OBJECTIVE: To study the self-medication for pain among students of medicine and nursing of the PUCSP compared with students from other knowledge areas. MATERIAL AND METHODS: Data were obtained in two groups: A - students from the health knowledge area, and B - students of law and engineering. It was used a questionnaire developed by the authors. Statistical analysis used the Chi-square test and the Fischer. RESULTS: In relation to gender, there is a predominance of women in the health group and a male majority in other one. In the health group there was a greater number of medical students, and in the control group of engineering. It is observed a high degree of selftreatment in both groups. It appears that participants in the health group have used more anti-inflammatory drugs and opioid than the others subjects studied. CONCLUSION: The frequency of medication for pain is higher in the group of health students, and self-medication is equally practiced among students of health and other areas.

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Objetivo: Estudar a automedicação para dor entre estudantes de cursos de medicina e enfermagem da PUCSP em comparação com estudantes das outras áreas de conhecimento. Material e métodos: Esses dados foram obtidos em dois grupos: A - estudantes da área da saúde e B - estudantes da área de ciências humanas e exatas. Utilizou-se um questionário elaborado pelos autores. A análise estatística usou o teste do qui-quadrado e de Fischer. Resultados: Na área de saúde há um predomínio do gênero feminino, e nas outras áreas um predomínio masculino. Na área de saúde a maior parte dos estudantes cursa medicina, e nas outras áreas engenharia. Observa-se um alto índice de automedicação em ambos os grupos, constatando-se que os participantes do grupo da área de saúde usam significativamente mais opioides e anti-inflamatórios que os demais estudados. Conclusão: A frequência do uso de medicamentos para dor é maior no grupo de estudantes da área de saúde, e a automedicação é praticada igualmente entre estudantes da área de saúde e das demais áreas. .

Objective: To study the self-medication for pain among students of medicine and nursing of the PUCSP compared with students from other knowledge areas. Material and methods: Data were obtained in two groups: A - students from the health knowledge area, and B - students of law and engineering. It was used a questionnaire developed by the authors. Statistical analysis used the Chi-square test and the Fischer. Results: In relation to gender, there is a predominance of women in the health group and a male majority in other one. In the health group there was a greater number of medical students, and in the control group of engineering. It is observed a high degree of selftreatment in both groups. It appears that participants in the health group have used more anti-inflammatory drugs and opioid than the others subjects studied. Conclusion: The frequency of medication for pain is higher in the group of health students, and self-medication is equally practiced among students of health and other areas. .

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