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Unraveling the antimicrobial mechanisms and multifunctional performance of boron-doped glass coatings on dental zirconias
No full textTo evaluate the mechanical, antimicrobial, and optical properties of boron-doped soda-lime glass coatings on 3Y-TZP and 5Y-PSZ zirconia. Disc-shaped specimens of 3Y-TZP and 5Y-PSZ were divided into: as-sintered (3Y-C and 5Y-C), coated with commercial glaze (3Y-G and 5Y-G), with soda-lime glass (3Y-SL and 5Y-SL), and with silver-containing soda-lime glass (3Y-SLAg and 5Y-SLAg). Cytotoxicity (MTT assay), biaxial flexural strength (σB), X-ray diffraction (XRD), translucency (TP00), color difference (ΔE00), and roughness (Ra and Rz) were conducted. Biofilm formation was quantified by colony-forming units (CFU/mL) of C. albicans, S. sanguinis, and E. coli. Scanning electron microscopy (SEM) and fractography were conducted. Energy-dispersive X-ray diffraction (EDS) was performed on SL and SLAg samples. Weibull modulus (m) and characteristic strength (σ0) for biaxial flexural strength (95 % CI) were calculated. All data were analyzed by two-way ANOVA, and Dunn's method, while the CFU test was analyzed by one-way ANOVA (α = 0.05). The experimental glasses did not induce cytotoxic effects. The flexural strength of 3Y-TZP groups showed highest values: 3Y-C(847.45 MPa); 3Y-G(843.22 MPa); 3Y-SL(806.41 MPa); 3Y-SLAg(769.04 MPa); 5Y-G(589.77 MPa); 5Y-SLAg (576.20 MPa); 5Y-C(479.44 MPa); 5Y-SL(474.00 MPa). Diffractograms showed tetragonal and cubic phases for all groups. Higher translucency values were observed for 5Y-PSZ groups, while for ΔE00 were similar. The SL and SLAg groups exhibited the lowest roughness values (Ra) for both zirconia. The 5Y-SL group exhibited antimicrobial effects against all tested microorganisms, while the 5Y-SLAg group showed antimicrobial effects against E. coli. Fractures originated at the zirconia surface, while for the 5Y-G group at the glaze layer. SEM micrographs revealed flower-shaped crystals for 3Y-SL, 5Y-SL and 5Y-SLAg groups. EDS identified zirconia in the crystal's composition. The 5Y-SL group exhibited a significant antimicrobial effect. This cytocompatible glass (5Y-SL) provided a superior antibiofilm effect compared to 5Y-SLAg. Moreover, the mechanical and optical properties of both 5Y-PSZ and 3Y-TZP zirconia were maintained.Department of Dental Materials and Prosthodontics Institute of Science and Technology São Paulo State University (UNESP)Department of Biosciences and Oral Diagnosis Institute of Science and Technology São Paulo State University (UNESP)Department of Prosthodontics and Periodontology Bauru School of Dentistry University of Sao Paulo (FOB-USP)Aeronautics Technological Institute (ITA) Physics DepartmentUniversity of Mississippi Medical Center (UMMC) Department of Biomedical Materials ScienceDepartment of Dental Materials and Prosthodontics Institute of Science and Technology São Paulo State University (UNESP)Department of Biosciences and Oral Diagnosis Institute of Science and Technology São Paulo State University (UNESP
Contrasting thermal and hypoxic responses of species from blackwater and whitewater rivers
No full textIn the Amazon basin, climate change is increasing water temperatures and CO₂ concentrations, which intensify environmental stressors for fish by increasing natural thermal regimes, reducing dissolved oxygen and pH levels. Extreme droughts, such as those recorded in 2023 and the new record set in 2024, have exacerbated these conditions and have led to widespread fish mortality. Amazonian rivers, which are characterized by contrasting whitewater and blackwater systems, provide unique habitats with distinct pHs and temperatures that shape biodiversity and species adaptations. With regional water temperatures projected to increase by 2.2–7.0°C by the end of the century, understanding the expected thermal vulnerability of Amazonian fish has become crucial. This study aims to investigate the influence of water type (blackwater vs. whitewater) on both thermal and hypoxia tolerances and hypoxia responses in different fish species following the extreme drought in 2023 and analyse these responses on individual and taxonomic levels. The results revealed significant variability in both thermal and hypoxia tolerances among species, with fish displaying a lower thermal safety margin in blackwaters. The contrasting thermal and hypoxia tolerances observed between blackwater and whitewater fishes highlight the complexity of their adaptive strategies in response to environmental stressors and are fundamental for predicting future conditions of the Amazonian environment under the current climate change scenario.Brazilian National Institute for Amazonian Research Laboratory of Ecophysiology and Molecular EvolutionSão Paulo State University (UNESP) Institute of BiosciencesSão Paulo State University (UNESP) Institute of Bioscience
Psychometric properties of the <i>Burnout Assessment Tool</i> - General version in nursing workers
No full textObjective: to analyze the validity evidence of the BAT - General version in a sample of Brazilian nursing workers. Method: a cross-sectional study design with non-probability sampling method was used among 3594 Brazilian nursing workers. The validity evidence was assessed by means of analysis based on the internal structure, on the relations to external variables, and on response process of the items. Results: the factor models of the BAT - General version showed goodness-of-fit to the data. However, the complete factor model enabled a better understanding of burnout syndrome in the sample. It was attested the BAT - General version dimensions were positively correlated with depression, anxiety and stress symptoms and negatively correlated with job satisfaction and satisfaction with life. The validity evidence analysis based on response process of the items revealed that BAT - General version works properly both in the group of nursing workers who reported having emotional or psychological health problems and in the group who denied these problems. Conclusion: the results provided robust validity evidence of the BAT - General version in Brazilian nursing workers.Univ Sao Paulo, Ctr Colaborador OPS OMS Desarrollo Invest Enfermer, Escola Enfermagem Ribeirao Preto, Ribeirao Preto, SP, BrazilUniv Estadual Paulista, Fac Ciencias Farmaceut, Araraquara, SP, BrazilUniv Fed Ciencias Saude, Dept Psicol, Porto Alegre, RS, BrazilConselho Fed Enfermagem, Brasilia, DF, BrazilKatholieke Univ Leuven, Fac Psychol & Educ Sci, Leuven, BelgiumBecaria Coordenacao Aperfeicoamento Pessoal Nivel, Curitiba, BrazilBecaria Conselho Nacl Desenvolvimento Cientif & Te, Sao Cristovao, BrazilUniv Estadual Paulista, Fac Ciencias Farmaceut, Araraquara, SP, Brazi
Ontogeny of adenohypophyseal cells, pituitary gland development, and structure in adults of Astyanax lacustris (Teleostei, Characiformes): an emerging Neotropical model fish species
No full textPituitary gland morphogenesis and the ontogeny of the adenohypophyseal (AH) cells of Astyanax lacustris are presented herein. This Characiformes species shows great ecological and commercial importance, and it has been increasingly used as animal model. For this study, A. lacustris specimens were collected from 0.5 to 120 days after hatching (dah) (adults). The entire animal or its head was appropriately fixed, and after histological processing, the sections were subjected to histochemical and immunohistochemical reactions, using homologous and heterologous antibodies. The first AH cells of A. lacustris were detected at 1 dah by the immunostaining of prolactin (PRL)-producing cells. The morphology of the gland presented changes in shape throughout the development, starting with elongation but more oval at the end. The neurohypophysis was differentiated at 3 dah, along with the identification of adrenocorticotropic hormone (ACTH), melanotropic hormone (MSH), thyroid-stimulating hormone (TSH), and follicle-stimulating hormone (FSH)-producing cells. Identification of the immunoreactive cells to anti-luteinizing hormone (LH), anti-somatolactin (SL), and anti-growth hormone (GH) antibodies occurred at 5 dah. At 20 dah, an increase in pituitary proportions and the presence of the pituitary stalk were observed. At 60 dah, the pituitary gland already had the same shape and distribution of AH cells seen in the adult. The ontogeny of adenohypophyseal cells in A. lacustris corroborates the heterogeneity in the appearance of these cell types in teleosts and suggests that these hormones actively participate during the post-hatching development of this species, even before the establishment of all endocrine axes. Our findings contribute to understanding the morphogenesis of the hypothalamic-pituitary axis in South American teleosts, providing essential data for the development of future studies related to pituitary gland morphophysiology under normal or experimental conditions.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fish Endocrinology Laboratory Department of Cell and Developmental Biology Institute of Biomedical Sciences University of São PauloLaboratory of Metabolism and Reproduction of Aquatic Organisms (LAMEROA), Department of Physiology, Biosciences Institute, University of São Paulo, Rua Do Matão, Lane 14, N. 101, Lab 220, São Paulo, São Paulo, CEP, 05508-000, BrazilFederal University of Triângulo Mineiro, Iturama University CampusDepartment of Structural and Functional Biology Institute of Biosciences São Paulo State University (UNESP)Department of Structural and Functional Biology Institute of Biosciences São Paulo State University (UNESP)FAPESP: 2014/23451-
Mass spectrometry-based identification reveals the polymicrobial nature of canine urinary tract infections
No full textCanine urinary tract infections (UTIs) are common in veterinary practice and often have a complex etiology. Typically, diagnoses rely on classical phenotypic tests or are limited to identifying the genus of the pathogen. Treatments are frequently administered without prior in vitro antimicrobial susceptibility testing. This study analyzed 389 urine samples from dogs with clinical signs of UTI, collected by cystocentesis, through microbiological culture. Species-level identification of bacteria and yeasts was performed using mass spectrometry, while bacterial isolates underwent antimicrobial susceptibility testing via the disk diffusion method. Of the 389 samples, 170 (43.7%) showed microbial growth, with 192 microorganisms identified. Among these, 98.4% (189/192) were bacteria, and 1.6% (3/192) were fungi/yeasts. The predominant pathogens included Enterobacteria (116/192 = 60%), enterococci (26/192 = 13.5%), and staphylococci (24/192 = 12.5%). Novel pathogens, such as Lactobacillus murinus and Stenotrophomonas maltophilia, were identified as primary agents of canine UTIs. Coinfections commonly involved E. coli with either E. faecalis (5/21 = 23.8%) or S. canis (4/21 = 19%). Amoxicillin/clavulanic acid was the most effective antimicrobial (≥ 70%), followed by amikacin and marbofloxacin (≥ 60%). Observed antimicrobial resistance rates included enterobacteria (18%), enterococci (> 40%), staphylococci (18%), streptococci (30%), Pseudomonas aeruginosa (60%), and other organisms (> 30%). Multidrug resistance affected 18% (34/189) of bacterial isolates. This study highlights the polymicrobial nature of canine UTIs and emphasizes concerns about multidrug-resistant bacteria. These findings contribute to improving molecular diagnostics and monitoring antimicrobial resistance in domestic animals, a critical global issue.Department of Animal Production and Preventive Veterinary Medicine School of Veterinary Medicine and Animal Science (FMVZ) São Paulo State University -UNESP, SPDepartment of Animal Production and Preventive Veterinary Medicine School of Veterinary Medicine and Animal Science (FMVZ) São Paulo State University -UNESP, S
Bacterial Multiresistance and Microbial Diversity of Milk Received by a University Hospital Milk Bank
No full textBreastfeeding is fundamental for the development and protection of the newborn, and microorganisms present in breast milk are associated with the development of the infant’s intestinal microbiota. However, there are factors that interfere with breastfeeding, resulting in the need to supply donated milk to milk banks for these children. Even though there is a restriction on medications prescribed for pregnant and breastfeeding women, some antimicrobials are accepted, as long as they are used correctly and as they can increase the selection pressure for resistant bacteria. The microorganisms present in breast milk from a human milk bank were evaluated and the resistance of the isolates to antimicrobials was phenotypically characterized. In total, 184 microbial isolates were identified by mass spectrometry, of 12 bacterial genera and 1 yeast genus. There was a high prevalence of bacteria of the genus Staphylococcus, mainly S. epidermidis (33%). Resistance to antimicrobials varied among species, with a higher percentage of isolates resistant to penicillins and macrolides. Multidrug resistance was identified in 12.6% of 143 isolates. Breast milk contains a wide variety of microorganisms, mainly those of the Staphylococcus and Enterobacter genera. There was a high percentage of resistant isolates, and multidrug resistance in Klebsiella oxytoca (66.7%; 4/6) and S. epidermidis (15.0%; 9/60) isolates, which increases the public health concern.School of Veterinary Medicine and Animal Science São Paulo State University (UNESP), Rua Prof. Doutor Walter Maurício Correa, s/nQualileite Laboratory Department of Animal Nutrition and Production University of São Paulo (USP, Avenida Duque de Caxias Norte, 225School of Veterinary Medicine and Animal Science São Paulo State University (UNESP), Rua Prof. Doutor Walter Maurício Correa, s/
Hydrothermal Green Synthesis of LaOx-Modified Pt/C Catalyst for Glycerol-to-Glycerate Electrooxidation in Alkaline Medium
No full textUsing the bromide anion exchange (BAE) green method to obtain carbon-supported nanoparticles, Pt(LaOx)/C was successfully prepared under mild conditions. This material, containing LaOx species generated in situ during the synthesis, was efficiently used as an anode to perform glycerol oxidation in alkaline medium in batch mode and at room temperature. In a direct alcohol fuel cell (DAFC), this catalyst was able to boost the glycerol-to-glycerate conversion with a 49% selectivity and a 28% power density higher than the same system using a BAE-synthesized Pt/C anode. The increase in catalytic activity may be due to the interaction of LaOx with the Pt active sites, acting as a bifunctional electrode. Furthermore, when used as an anode in an electrolysis setup, the selectivity of glycerol toward glycerate increased up to 67%. In situ FTIR and HPLC analyses confirmed the formation of the value-added glycerol oxidation products.Electricité de FranceDepartment of Chemistry Faculty of Philosophy Science and Letters at Ribeirão Preto University of São Paulo, São PauloUniversité de Poitiers IC2MP UMR 7285 CNRS Équipe SAMCat, 4 rue Michel Brunet, B27, TSA 51106UNESP – National Institute of Alternative Technologies for Detection Toxicological Evaluation and Removal of Micropollutants and Radioactive Substances (INCT-DATREM), Rua Prof. Francisco Degni, 55UNESP – National Institute of Alternative Technologies for Detection Toxicological Evaluation and Removal of Micropollutants and Radioactive Substances (INCT-DATREM), Rua Prof. Francisco Degni, 55Electricité de France: R-2024-3
Silicon, by modulating homeostasis and nutritional efficiency, increases the antioxidant action and tolerance of bell peppers to phosphorus deficiency
No full textThe effects of phosphorus deficiency on bell pepper cultivation and the role of silicon in mitigating this deficiency warrant further investigation. The use of silicon could be a promising sustainable alternative to increase the tolerance of this vegetable to P-deficient environments, which is a worldwide issue, but the mechanisms involved need to be elucidated. To this end, this research aimed to investigate the impact of Si on mitigating P deficiency in bell pepper plants, exploring its effects on nutritional homeostasis and physiological parameters under conditions of P sufficiency and deficiency. This study was conducted under controlled conditions with two P conditions (deficiency and sufficiency) combined with two Si conditions (0.0 and 2.0 mM) arranged in a completely randomized design with five repetitions. We found that P deficiency damage in bell pepper plants compromised the nutritional efficiencies of P and N, photochemical efficiency, total soluble sugar production, and growth, but the adaptive response of the plant to mitigate these damages induced non-enzymatic antioxidant defense mechanisms and favored homeostasis by increasing the C/N, C/P, and N/P ratios. This occurred because Si favored stoichiometric homeostasis of C/N, C/P, and N/P in the plant while simultaneously reducing stress with substantial increases in the production of antioxidant compounds, such as ascorbic acid, phenolic compounds, anthocyanin, carotenoids, and photosynthetic pigments, enhancing photochemical efficiency and C use, and consequently, plant growth. This study offers a sustainable option for addressing P deficiency using Si, strengthening large-scale horticulture, given the common occurrence of P-limited growing environments.Universidade Estadual PaulistaDepartment of Soil Science School of Agricultural and Veterinarian Sciences São Paulo State University “Júlio Mesquita Filho”, Av. Prof. Paulo Donato CastellaneDepartment of Soil Science School of Agricultural and Veterinarian Sciences São Paulo State University “Júlio Mesquita Filho”, Av. Prof. Paulo Donato Castellan
Efect of human-modified landscapes on the occupancy of threatened small mammals in the Atlantic Forest of São Paulo
No full textA Mata Atlântica é um ecossistema prioritário para a conservação global da biodiversidade, atualmente composta em sua maioria de fragmentos florestais menores de 50 ha. A perda e a fragmentação do habitat na escala de paisagem afeta as comunidades, sendo os requisitos ecológicos das espécies um fator determinante das respostas à perda de vegetação. Este estudo buscou avaliar como a cobertura florestal, a heterogeneidade da paisagem e as matrizes antrópicas influenciam a ocorrência de três espécies florestais de pequenos mamíferos - Euryoryzomys russatus, Thaptomys nigrita e Monodelphis iheringi - ameaçados no Estado de São Paulo. Foi estabelecido um raio de 1000 m sobre 13 paisagens compostas por gradientes de cobertura florestal entre 6% e 96% e matrizes de origem antrópica (agricultura, pastagem e silvicultura), utilizando armadilhas live-traps, modelo “Sherman”, com iscas. Para obter as métricas de paisagem foram utilizadas informações sobre a porcentagem de cobertura florestal, agricultura-pastagem e de silvicultura, densidade de fragmentos de floresta, produtividade (através de índice de vegetação-EVI) e heterogeneidade da vegetação (textura do EVI). Utilizamos modelos de ocupação single-species-single-season para avaliar como as características da paisagem influenciam a ocorrência de espécies foco na Mata Atlântica, controlando para fatores de detecção (esforço amostral, tipo de armadilha e condições climáticas). A análise dos modelos ocorreu em duas etapas: (1) seleção da melhor estrutura para detecção (ρ) e (2) teste de covariáveis de ocupação (ψ), utilizando critério de seleção de Akaike - AICc. O esforço amostral totalizou 29.160 armadilhas-noite, 64 capturas das três espécies e sucesso de captura de 0.12% para E. russatus, 0.6% para M. iheringi e 0.4% para T. nigrita. As capturas ocorreram em floresta (87.5%), sítios de eucalipto (10.94%) e pastagem com apenas uma captura. Não houve captura em sítios de agricultura. Além das espécies foco, outras quatro espécies quase ameaçadas e uma pouco conhecida também foram registradas. Embora os modelos não tenham conseguido indicar um efeito claro das variáveis de paisagens, observou-se indícios que as paisagens compostas por áreas com maior cobertura florestal e menor mosaico agricultura-pastagem foram mais propícias à ocupação de E. russatus e T. nigrita e houve indícios da influência positiva da heterogeneidade espacial da vegetação na ocupação de M. iheringi. Considerando os resultados e informações disponíveis na 5 literatura, as estratégias efetivas para conservação destas espécies são a preservação das florestas, contínuas ou bem conectadas, além do manejo das matrizes para que conservem características favoráveis à ocorrência das espécies foco, beneficiando inclusive outras espécies possivelmente em declínio na região. Também recomendamos em trabalhos futuros a inclusão da amostragem dos diferentes tipos de matriz, sendo essas informações úteis para auxiliar no manejo de paisagens fragmentadas.The Atlantic Forest is a highly degraded ecosystem, mostly composed of forest fragments smaller than 50 ha. Habitat loss and fragmentation at the landscape scale affect communities, with species' habitat requirements being a key factor in their responses to vegetation loss. This study aimed to evaluate how forest cover, landscape heterogeneity, and anthropogenic matrices influence the occurrence of three forest-dwelling small mammal species — Euryoryzomys russatus, Thaptomys nigrita, and Monodelphis iheringi — which are threatened in the state of São Paulo. Thirteen 1000 m-radius landscapes were sampled, covering forest cover gradients ranging from 6% to 96% and different anthropogenic matrices (agriculture, pasture, and silviculture). Live traps (Sherman model) with bait were used for sampling. Landscape metrics included the percentage of forest cover, agriculture-pasture, and silviculture, forest fragment density, productivity (using the Enhanced Vegetation Index—EVI), and vegetation heterogeneity (EVI texture). We applied single-species, single-season occupancy models to assess how landscape characteristics influence the occurrence of the target species in the Atlantic Forest, while controlling for detection factors (sampling effort, trap type, and weather conditions). Model analysis followed two steps: (1) selection of the best detection structure (ρ) and (2) testing of occupancy covariates (ψ) using Akaike’s Information Criterion (AICc). The total sampling effort amounted to 29,160 trap-nights, resulting in 64 captures of the three species, with capture success rates of 0.12% for E. russatus, 0.6% for M. iheringi, and 0.4% for T. nigrita. Captures occurred mainly in forests (87.5%), eucalyptus plantations (10.94%), and pasture (only one capture), with no captures in agricultural sites. Besides the target species, four near-threatened species and one poorly known species were also recorded. Although the models did not clearly indicate the effect of landscape variables, there were indications that landscapes with higher forest cover and lower agriculture-pasture mosaics were more favorable for the occupancy of E. russatus and T. nigrita, while spatial vegetation heterogeneity appeared to positively influence M. iheringi. Considering the results and available literature, effective conservation strategies for these species include preserving continuous or well-connected forests and managing matrices to maintain favorable conditions for the target species, which would also benefit other potentially declining species in the region. We also recommend that future studies include sampling across different matrix types, as this information would be useful for managing fragmented landscapes
Analog implementation of a high-gain sliding mode controller applied to a two-beam interferometer
No full textEste trabalho tem como objetivo o desenvolvimento de um controlador analógico por modos deslizantes com alto ganho, aplicado a um interferômetro em quadratura. A proposta é inspirada em pesquisas anteriores realizadas no Laboratório de Optoeletrônica (LOE) da Faculdade de Engenharia de Ilha Solteira, visando superar limitações de desempenho em frequências além de 500 Hz e propor uma solução de baixo custo que dispense algoritmos de desdobramento de fase. Para isso, foi projetado um controlador que passou por testes experimentais utilizando o interferômetro de Michelson modificado. Os resultados apresentaram erros de até 10%, atribuídos ao chaveamento, ao baixo ganho do sistema e a ruídos eletrônicos — desafios que ainda precisam ser superados. No entanto, esses resultados forneceram subsídios importantes para ajustes futuros, pois os problemas identificados podem ser mitigados com o uso de componentes eletrônicos mais precisos, aumento do ganho e a possível atualização para um observador implementado de forma analógica.This work aims to develop a high-gain sliding mode controller applied to a quadrature interferometer. The approach is inspired by previous research carried out at the Laboratório de Optoeletrônica (LOE) of the University of Engineering of Ilha Solteira, with the goal of overcoming performance limitations at high frequencies (above 500 Hz) and proposing a low-cost solution that eliminates the need for phase unwrapping algorithms. To this end, a controller was designed and subjected to experimental tests using a modified Michelson interferometer. The results showed errors of up to 10%, attributed to switching effects, low system gain, and electronic noise — challenges that still need to be addressed. Nevertheless, these results provided valuable insights for future adjustments, as the identified issues can be mitigated by using more precise electronic components, increasing system
gain, and potentially upgrading to a virtually implemented analog closed-loop system