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1.
PLoS Biol ; 22(2): e3002497, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38358955

RESUMO

Online digital data from media platforms have the potential to complement biodiversity monitoring efforts. We propose a strategy for integrating these data into current biodiversity datasets in light of the Kunming-Montreal Global Biodiversity Framework.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais
2.
Proc Natl Acad Sci U S A ; 119(38): e2209514119, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36048924

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cell entry starts with membrane attachment and ends with spike (S) protein-catalyzed membrane fusion depending on two cleavage steps, namely, one usually by furin in producing cells and the second by TMPRSS2 on target cells. Endosomal cathepsins can carry out both. Using real-time three-dimensional single-virion tracking, we show that fusion and genome penetration require virion exposure to an acidic milieu of pH 6.2 to 6.8, even when furin and TMPRSS2 cleavages have occurred. We detect the sequential steps of S1-fragment dissociation, fusion, and content release from the cell surface in TMPRRS2-overexpressing cells only when exposed to acidic pH. We define a key role of an acidic environment for successful infection, found in endosomal compartments and at the surface of TMPRSS2-expressing cells in the acidic milieu of the nasal cavity.


Assuntos
COVID-19 , Cavidade Nasal , SARS-CoV-2 , Serina Endopeptidases , Internalização do Vírus , COVID-19/virologia , Furina/genética , Furina/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Cavidade Nasal/química , Cavidade Nasal/virologia , SARS-CoV-2/fisiologia , Serina Endopeptidases/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo
3.
Conserv Biol ; 38(1): e14161, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37551776

RESUMO

Citizen science plays a crucial role in helping monitor biodiversity and inform conservation. With the widespread use of smartphones, many people share biodiversity information on social media, but this information is still not widely used in conservation. Focusing on Bangladesh, a tropical megadiverse and mega-populated country, we examined the importance of social media records in conservation decision-making. We collated species distribution records for birds and butterflies from Facebook and Global Biodiversity Information Facility (GBIF), grouped them into GBIF-only and combined GBIF and Facebook data, and investigated the differences in identifying critical conservation areas. Adding Facebook data to GBIF data improved the accuracy of systematic conservation planning assessments by identifying additional important conservation areas in the northwest, southeast, and central parts of Bangladesh, extending priority conservation areas by 4,000-10,000 km2 . Community efforts are needed to drive the implementation of the ambitious Kunming-Montreal Global Biodiversity Framework targets, especially in megadiverse tropical countries with a lack of reliable and up-to-date species distribution data. We highlight that conservation planning can be enhanced by including available data gathered from social media platforms.


Registros de las redes sociales para guiar la planeación de la conservación Resumen La ciencia ciudadana es importante para monitorear la biodiversidad e informar la conservación. Con el creciente uso de los teléfonos inteligentes, muchas personas comparten información de la biodiversidad en redes sociales, pero todavía no se usa ampliamente en la conservación. Analizamos la importancia de los registros de las redes sociales para las decisiones de conservación enfocados en Bangladesh, un país tropical megadiverso y mega poblado. Cotejamos los registros de distribución de especies de aves y mariposas en Facebook y Global Biodiversity Information Facility (GBIF), las agrupamos en datos sólo de GBIF o datos combinados de Facebook y GBIF e investigamos las diferencias en la identificación de las áreas de conservación críticas. La combinación de los datos de Facebook con los de GBIF mejoró la precisión de las evaluaciones de la planeación de la conservación sistemática al identificar otras áreas importantes de conservación en el noroeste, sureste y centro de Bangladesh, extendiendo así las áreas prioritarias de conservación en unos 4,000-10,000 km2 . Se requieren esfuerzos comunitarios para impulsar la implementación de los objetivos ambiciosos del Marco Global de Biodiversidad Kunming-Montreal, especialmente en países tropicales que carecen de datos confiables y actuales sobre la distribución de las especies. Destacamos que la planeación de la conservación puede mejorarse si se incluye información tomada de las redes sociales.


Assuntos
Borboletas , Mídias Sociais , Humanos , Animais , Conservação dos Recursos Naturais , Biodiversidade , Aves
4.
BMC Med Inform Decis Mak ; 24(1): 99, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637866

RESUMO

BACKGROUND: The literature is consensual regarding the academic community exhibiting higher levels of mental disorder prevalence than the general population. The potential of digital mental health apps for improving access to resources to cope with these issues is ample. However, studies have yet to be performed in Portugal on individuals' attitudes and perceptions toward digital mental health applications or their preferences and decision drivers on obtaining mental health care, self-assessment, or treatment. OBJECTIVE: This study aims to understand the determinants of digital mental health applications use in the Portuguese academic community of Porto, along with potential adoption barriers and enablers. METHODS: A cross-sectional, web-based survey was delivered via dynamic email to the University of Porto's academic community. Data collection occurred between September 20 and October 20, 2022. We used structural equation modeling to build three models, replicating a peer-reviewed and published study and producing a newly full mediation model shaped by the collected data. We tested the relationships between use of digital mental health apps and perceived stress, perceived need to seek help for mental health, perceived stigma, past use of mental health services, privacy concerns, and social influence. RESULTS: Of the 539 participants, 169 (31.4%) reported having used digital mental health apps. Perceived stress and a latent variable, comprising perceptions of mental health problems and coping strategies, were positively associated with mental health app use, while privacy concerns regarding one's information being accessible to others were negatively associated. Perceived stigma, need to seek help, and close relationships did not have a statistically significant direct effect. CONCLUSIONS: These findings can inform product and policy development of new, better-targeted digital mental health app interventions, with implications for researchers and academia, industry, and policymakers. Our study concludes that, to maximize adherence to these apps, they should have low to no financial charges, demonstrate evidence of their helpfulness and focus on the timely delivery of care. We also conclude that to foster digital mental health app use, there is a need to improve mental health literacy, namely regarding self-awareness of one's conditions, acceptable stress levels, and overall behavior towards mental health. TRIAL REGISTRATION: RR2-10.2196/41040.


Assuntos
Saúde Mental , Aplicativos Móveis , Humanos , Portugal , Estudos Transversais , Inquéritos e Questionários , Internet
5.
Cell Physiol Biochem ; 57(2): 63-81, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36945889

RESUMO

BACKGROUND/AIMS: Titanium dioxide nanoparticles (TiO2 NPs) are extensively applied in the industry due to their photocatalytic potential, low cost, and considerably low toxicity. However, new unrelated physicochemical properties and the wide use of nanoparticles brought concern about their toxic effects. Thereby, we evaluated the cytotoxicity of a TiO2 NP composed of anatase and functionalized with sodium carboxylate ligands in a murine fibroblast cell line (LA-9). METHODS: Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), and ATR-FTIR spectroscopy were applied to determine nanoparticle physicochemical properties. The cell viability (MTT assay) and clonogenic survival were analyzed in fibroblasts exposed to TiO2 NP (50, 150, and 250 µg/mL) after 24h. Moreover, oxidative stress, proinflammatory state, and apoptosis were evaluated after 24h. RESULTS: TiO2 NP characterization showed an increased hydrodynamic size (3.57 to 7.62 nm) due to solvent composition and a heterogeneity dispersion in water and cell culture media. Also, we observed a zeta potential increased from -20 to -11 mV in function of protein adsorption. TiO2 NP reduced fibroblast cell viability and induced ROS production at the highest concentrations (150 and 250 µg/mL). Moreover, TiO2 NP reduced the fibroblasts clonogenic survival at the highest concentration (250 µg/mL) on the 7th day after the 24h exposure. Nevertheless, TiO2 NP did not affect the fibroblast proinflammatory cytokines (IL-6 and TNF) secretion at any condition. Early and late apoptotic fibroblast cells were detected only at 150 µg/mL TiO2 NP after 24h. CONCLUSION: Probably, TiO2 NP photocatalytic activity unbalanced ROS production which induced apoptosis and consequently reduced cell viability and metabolic activity at higher concentrations.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Camundongos , Animais , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/química , Espécies Reativas de Oxigênio/metabolismo , Nanopartículas/toxicidade , Nanopartículas/química , Titânio/química , Linhagem Celular , Fibroblastos/metabolismo , Sobrevivência Celular
6.
Biotechnol Bioeng ; 120(9): 2588-2600, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36919374

RESUMO

The insect cell-baculovirus expression vector system (IC-BEVS) has shown to be a powerful platform to produce complex biopharmaceutical products, such as recombinant proteins and virus-like particles. More recently, IC-BEVS has also been used as an alternative to produce recombinant adeno-associated virus (rAAV). However, little is known about the variability of insect cell populations and the potential effect of heterogeneity (e.g., stochastic infection process and differences in infection kinetics) on product titer and/or quality. In this study, transcriptomics analysis of Sf9 insect cells during the production of rAAV of serotype 2 (rAAV2) using a low multiplicity of infection, dual-baculovirus system was performed via single-cell RNA-sequencing (scRNA-seq). Before infection, the principal source of variability in Sf9 insect cells was associated with the cell cycle. Over the course of infection, an increase in transcriptional heterogeneity was detected, which was linked to the expression of baculovirus genes as well as to differences in rAAV transgenes (rep, cap and gfp) expression. Noteworthy, at 24 h post-infection, only 29.4% of cells enclosed all three necessary rAAV transgenes to produce packed rAAV2 particles, indicating limitations of the dual-baculovirus system. In addition, the trajectory analysis herein performed highlighted that biological processes such as protein folding, metabolic processes, translation, and stress response have been significantly altered upon infection. Overall, this work reports the first application of scRNA-seq to the IC-BEVS and highlights significant variations in individual cells within the population, providing insight into the rational cell and process engineering toward improved rAAV2 production in IC-BEVS.


Assuntos
Dependovirus , Vetores Genéticos , Animais , Dependovirus/genética , Transcriptoma/genética , Análise da Expressão Gênica de Célula Única , Células Sf9 , Baculoviridae/genética , Baculoviridae/metabolismo , Insetos
7.
Biotechnol Bioeng ; 120(9): 2578-2587, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37027346

RESUMO

The majority of recombinant adeno-associated viruses (rAAV) approved for clinical use or in clinical trials areproduced by transient transfection using the HEK293 cell line. However, this platform has several manufacturing bottlenecks at commercial scales namely, low product quality (full to empty capsid ratio <20% in most rAAV serotypes), lower productivities obtained after scale-up and the high cost of raw materials, in particular of Good Manufacturing Practice grade plasmid DNA required for transfection. The HeLa-based stable cell line rAAV production system provides a robust and scalable alternative to transient transfection systems. Nevertheless, the time required to generate the producer cell lines combined with the complexity of rAAV production and purification processes still pose several barriers to the use of this platform as a suitable alternative to the HEK293 transient transfection. In this work we streamlined the cell line development and bioprocessing for the HeLaS3-based production of rAAV. By exploring this optimized approach, producer cell lines were generated in 3-4 months, and presented rAAV2 volumetric production (bulk) > 3 × 1011 vg/mL and full to empty capsids ratio (>70%) at 2 L bioreactor scale. Moreover, the established downstream process, based on ion exchange and affinity-based chromatography, efficiently eliminated process related impurities, including the Adenovirus 5 helper virus required for production with a log reduction value of 9. Overall, we developed a time-efficient and robust rAAV bioprocess using a stable producer cell line achieving purified rAAV2 yields > 1 × 1011 vg/mL. This optimized platform may address manufacturing challenges for rAAV based medicines.


Assuntos
Dependovirus , Vetores Genéticos , Humanos , Dependovirus/genética , Células HEK293 , Células HeLa , Transfecção
8.
PLoS Biol ; 18(10): e3000935, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33119582

RESUMO

The ongoing digital revolution in the age of big data is opening new research opportunities. Culturomics and iEcology, two emerging research areas based on the analysis of online data resources, can provide novel scientific insights and inform conservation and management efforts. To date, culturomics and iEcology have been applied primarily in the terrestrial realm. Here, we advocate for expanding such applications to the aquatic realm by providing a brief overview of these new approaches and outlining key areas in which culturomics and iEcology are likely to have the highest impact, including the management of protected areas; fisheries; flagship species identification; detection and distribution of threatened, rare, and alien species; assessment of ecosystem status and anthropogenic impacts; and social impact assessment. When deployed in the right context with awareness of potential biases, culturomics and iEcology are ripe for rapid development as low-cost research approaches based on data available from digital sources, with increasingly diverse applications for aquatic ecosystems.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Animais Selvagens/fisiologia , Viés , Espécies em Perigo de Extinção , Pesqueiros
9.
Conserv Biol ; 37(5): e14100, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37070377

RESUMO

The first target of the Convention for Biological Diversity (Aichi target 1) was to increase public awareness of the values of biodiversity and actions needed to conserve it-a key prerequisite for other conservation targets. Monitoring success in achieving this target at a global scale has been difficult; however, increased digitization of human life in recent decades has made it easier to measure people's interests at an unprecedented scale and allows for a more comprehensive evaluation of Aichi target 1 than previously attempted. We used Google search volume data for over a thousand search terms related to different aspects of biodiversity and conservation to evaluate global interest in biodiversity and its conservation. We also investigated the correlation of interest in biodiversity and conservation across countries to variables related to biodiversity, economy, demography, research, education, internet use, and presence of environmental organizations. From 2013 to 2020, global searches for biodiversity components increased, driven mostly by searches for charismatic fauna (59% of searches were for mammal species). Searches for conservation actions, driven mostly by searches for national parks, decreased since 2019, likely due to the COVID-19 pandemic. Economic inequality was negatively correlated with interest in biodiversity and conservation, whereas purchasing power was indirectly positively correlated with higher levels of education and research. Our results suggest partial success toward achieving Aichi target 1 in that interest in biodiversity increased widely, but not for conservation. We suggest that increased outreach and education efforts aimed at neglected aspects of biodiversity and conservation are still needed. Popular topics in biodiversity and conservation could be leveraged to increase awareness of other topics with attention to local socioeconomic contexts.


Evaluación del interés mundial en la biodiversidad y la conservación Resumen La primera meta del Convenio sobre la Diversidad Biológica (Meta 1 de Aichi) era aumentar la conciencia pública sobre los valores de la biodiversidad y las acciones necesarias para conservarla, un requisito previo clave para otras metas de conservación. Ha sido difícil monitorear el éxito en la obtención de esta meta a escala mundial; sin embargo, la creciente digitalización de la vida humana en las últimas décadas ha facilitado la medición de los intereses de la gente a una escala sin precedentes y permite una evaluación más exhaustiva de la Meta 1 de Aichi que la que se había intentado previamente. Utilizamos datos sobre el volumen de búsquedas en Google de más de mil términos relacionados con distintos aspectos de la biodiversidad y la conservación para evaluar el interés mundial en la biodiversidad y su conservación. También investigamos la correlación del interés por la biodiversidad y la conservación en los distintos países con variables relacionadas a la biodiversidad, la economía, la demografía, la investigación, la educación, el uso del internet y la presencia de organizaciones ambientalistas. Las búsquedas mundiales sobre los componentes de la biodiversidad aumentaron de 2013 a 2020, impulsadas sobre todo por búsquedas de especies carismática (el 59% de las búsquedas correspondían a especies de mamíferos). Las búsquedas de acciones de conservación, impulsadas principalmente por búsquedas de parques nacionales, han disminuido desde 2019, probablemente debido a la pandemia de COVID-19. La desigualdad económica se correlacionó negativamente con el interés en la biodiversidad y la conservación, mientras que el poder adquisitivo se correlacionó indirectamente de manera positiva con niveles más altos de educación e investigación. Nuestros resultados sugieren un éxito parcial en la obtención de la Meta 1 de Aichi en el sentido de que aumentó ampliamente el interés por la biodiversidad, pero no por la conservación. Sugerimos que se necesitan mayores esfuerzos de divulgación y educación dirigidos a aspectos desatendidos de la biodiversidad y la conservación. Los temas populares de biodiversidad y conservación podrían aprovecharse para aumentar la conciencia sobre otros temas si se presta atención a los contextos socioeconómicos locales.


Assuntos
COVID-19 , Pandemias , Animais , Humanos , Conservação dos Recursos Naturais/métodos , Biodiversidade , Mamíferos
10.
Appl Microbiol Biotechnol ; 107(11): 3699-3716, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37083969

RESUMO

Fungal colorants are gradually entering the global color market, given their advantages of being less harmful to human health, as well as having greater stability and biotechnological potential, compared to other natural sources. The present work concerns the isolation and identification of an endophytic filamentous fungus, together with the chemical characterization and assessment of the fluorescence, toxicity, stability, and application potential of its synthesized red colorant. The endophytic fungus was isolated from Hymenaea courbaril, a tree from the Brazilian savannah, and was identified as Talaromyces minnesotensis by phenotypic and genotypic characterization. Submerged cultivation of the fungus resulted in the production of approximately 12 AU500 of a red biocolorant which according to LC-DAD-MS analysis is characterized by being a complex mixture of molecules of the azaphilone class. Regarding cytotoxicity assays, activity against human hepatoblastoma (HepG2) cells was only observed at concentrations above 5.0 g L-1, while antimicrobial effects against pathogenic bacteria and yeast occurred at concentrations above 50.0 g L-1. The biocolorant showed high stability at neutral pH values and low temperatures (10 to 20 °C) and high half-life values (t1/2), which indicates potential versatility for application in different matrices, as observed in tests using detergent, gelatin, enamel, paint, and fabrics. The results demonstrated that the biocolorant synthesized by Talaromyces minnesotensis has potential for future biotechnological applications. KEY POINTS: • An endophytic fungus, which was isolated and identified, synthesize a red colorant. • The colorant showed fluorescence property, low toxicity, and application potential. • The red biocolorant was highly stable at pH 8.0 and temperatures below 20°C.


Assuntos
Talaromyces , Humanos , Temperatura , Temperatura Baixa , Alimentos , Concentração de Íons de Hidrogênio , Saccharomyces cerevisiae
11.
BMC Health Serv Res ; 23(1): 454, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37158887

RESUMO

INTRODUCTION: Time optimization is a common goal to most health information institutions. In several countries, chronic electronic renewal prescriptions were one of the main focuses when implementing information systems. In Portugal, Electronic Medical Prescription (PEM®) software is used for most electronic prescriptions. This study aims to quantify the time spent in chronic prescription renewal appointments (CPRA) in primary care and its impact in the Portuguese National Health System (SNS). METHODS: Eight general practitioners (GP) were included in the study during February 2022. The average duration of 100 CPRA was obtained. To determine the number of CPRA performed every year, a primary care BI-CSP® platform was used. Using Standard Cost Model and average medical doctor hourly rate in Portugal we estimated CPRA global costs. RESULTS: Each doctor spent on average 1:55 ± 01:07 min per CPRA. There were 8295 GP working in 2022. A total 635 561 CPRA were performed in 2020 and 774 346 in 2021. In 2020, CPRA costs ranged 303 088 ± 179 419€, and in 2021 that number increased to 369 272 ± 218 599€. CONCLUSION: This is the first study to quantify CPRA's real cost in Portugal. A PEM® software update would allow daily savings, ranging from 830€ (± 491€) in 2020 and 1011€ (± 598€) in 2021. That change could allow hiring 8 ± 5 GP in 2020 and 12 ± 7 in 2021.


Assuntos
Clínicos Gerais , Prescrições , Humanos , Etnicidade , Renda , Atenção Primária à Saúde
12.
Int J Sports Med ; 44(1): 56-63, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36002028

RESUMO

The study aimed to assess the effect of different front crawl stroke rates (SRs) in the oxygen uptake (̇VO2) kinetics and ̇VO2 peak, the total time to exhaustion (TTE), and blood lactate concentration ([La]) at 95% of the 400-m front crawl test (T400) mean speed (S400). Twelve endurance swimmers performed a T400 and four trials at 95% of the S400: (i) free SR, (ii) fixed SR (100% of the average free SR trial), (iii) reduced SR (90% of the average free SR trial), and (iv) increased SR (110% of the average free SR trial). ̇VO2 was accessed continuously with breath-by-breath analysis. The results highlighted: (i) the time constant at increased SR (13.3±4.2 s) was lower than in the reduced SR condition (19.5±2.6 s); (ii) the amplitude of the primary phase of ̇VO2 kinetics in the fixed SR (44.0±5.8 ml·kg-1·min-1) was higher than in the increased SR condition (39.5±6.4 ml·kg-1·min-1); and (iii) TTE was lower in the fixed SR (396.1±189.7 s) than the increased SR condition (743.0±340.0 s). The results indicate that controlled SR could be considered a swimming training strategy, focusing on physiological parameters overload.


Assuntos
Consumo de Oxigênio , Natação , Humanos , Natação/fisiologia , Consumo de Oxigênio/fisiologia , Testes Respiratórios , Ácido Láctico , Cinética , Oxigênio
13.
Sens Actuators B Chem ; 353: 131157, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35177879

RESUMO

This work reports an optical fibre probe functionalised with 'cotton-shaped' gold-silica nanostructures for relative humidity (RH) monitoring. The sensor response utilises the localised surface plasmon resonance (LSPR) of self-assembled nanostructures: gold nanospheres (40 nm) surrounded by one layer of poly (allylamine hydrochloride) and hydrophilic silica nanoparticles (10-20 nm) on the end-facet of an optical fibre via a wavelength shift of the reflected light. Sensor optimisation is investigated by varying the density of gold nanoparticles on the end-facet of an optical fibre. It is demonstrated that the plasmonic hybridisation mode appearing when the average gold interparticle distance is small (Median: 7.5 nm) is more sensitive to RH after functionalisation than the singular plasmonic mode. The plasmonic hybridisation mode sensor demonstrates a high linear regression to RH with a sensitivity of 0.63 nm/%RH and excellent reversibility. The response time (T10-90%) and recovery time (T90-10%) are calculated as 1.2 ± 0.4 s and 0.95 ± 0.18 s. The sensor shows no measurable cross-talk to temperature in the tested range between 25 °C to 40 °C and the 95% limit of agreement is 3.1%RH when compared to a commercial reference sensor. Simulation with finite element analysis reveals a polarisation-dependent plasmonic hybridisation with a redshift of plasmonic wavelength as a decrease of the interparticle distance and a higher refractive index sensitivity, which results in a high sensitivity to RH as observed in the experiment.

14.
J Toxicol Environ Health A ; 85(16): 649-670, 2022 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-35469539

RESUMO

The increase in large-scale production of magnetic nanoparticles (NP) associated with the incomplete comprehensive knowledge regarding the potential risks of their use on environmental and human health makes it necessary to study the biological effects of these particles on organisms at the cellular level. The aim of this study to examine the cellular effects on fibroblast lineage LA-9 after exposure to mixed iron oxide NP (Fe3O4 NP). The following analyses were performed: field emission gun-scanning electron microscopy (SEM-FEG), dynamic light scattering (DLS), zeta potential, ultraviolet/visible region spectroscopy (UV/VIS), and attenuated total reactance-Fourier transform infrared (ATR-FTIR) spectroscopy analyses for characterization of the NP. The assays included cell viability, morphology, clonogenic potential, oxidative stress as measurement of reactive oxygen species (ROS) and nitric oxide (NO) levels, cytokines quantification interleukin 6 (IL-6) and tumor necrosis factor (TNF), NP uptake, and cell death. The size of Fe3O4 NP was 26.3 nm when evaluated in water through DLS. Fe3O4 NP did not reduce fibroblast cell viability until the highest concentration tested (250 µg/ml), which showed a decrease in clonogenic potential as well as small morphological changes after exposure for 48 and 72 hr. The NP concentration of 250 µg/ml induced enhanced ROS and NO production after 24 hr treatment. The uptake assay exhibited time-dependent Fe3O4 NP internalization at all concentrations tested with no significant cell death. Hence, exposure of fibroblasts to Fe3O4 NP-induced oxidative stress but not reduced cell viability or death. However, the decrease in the clonogenic potential at the highest concentration demonstrates cytotoxic effects attributed to Fe3O4 NP which occurred on the 7th day after exposure.


Assuntos
Nanopartículas , Animais , Fibroblastos , Humanos , Ferro/metabolismo , Nanopartículas Magnéticas de Óxido de Ferro , Camundongos , Nanopartículas/química , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
15.
An Acad Bras Cienc ; 94(suppl 2): e20210395, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35830093

RESUMO

Social media data is a rich source of information to assess human activities in catastrophic events. Here, we use social media data to understand how the 2019 Brazilian oil spill influenced social attitudes. Data were collected from the globally popular Instagram platform between August 1, 2019 and March 1, 2020. First, we manually identified the 5 most popular (portuguese language) hashtags related to the oil spill #oleonononordeste; #desastreambiental; #marsemoleo; #sosnordeste; #marsempetroleo. In the sequence, we collected information on captions, post metadata and users associated with posts retrieved using the selected hashtags. We identified a total of 7,413 posts. These posts were grouped in topics: government (47.76%), protest (24.37%), volunteers (24.45%), biodiversity (0.003%), origin (0.006%), tourism (0.008%) and others (0.016%). All topics had the peak of posts in October and November 2019. Nevertheless, interest in the oil spill was temporary, with most posts appearing in the 2-4 months after the beginning of the disaster. Our findings illustrate the enormous potential of using social media data for understanding and monitoring human engagement with environmental disasters, but also suggest that conservationists and environmental groups may only have a limited 'window of opportunity' to engage and mobilize public support for remediation and restoration efforts.


Assuntos
Poluição por Petróleo , Mídias Sociais , Brasil , Humanos , Poluição por Petróleo/efeitos adversos
16.
Mikrochim Acta ; 190(1): 40, 2022 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-36585475

RESUMO

Laser-induced graphene (LIG) is as a promising material for flexible microsupercapacitors (MSCs) due to its simple and cost-effective processing. However, LIG-MSC research and production has been centered on non-sustainable polymeric substrates, such as polyimide. In this work, it is presented a cost-effective, reproducible, and robust approach for the preparation of LIG structures via a one-step laser direct writing on chromatography paper. The developed strategy relies on soaking the paper in a 0.1 M sodium tetraborate solution (borax) prior to the laser processing. Borax acts as a fire-retardant agent, thus allowing the laser processing of sensitive substrates that other way would be easily destroyed under the high-energy beam. LIG on paper exhibiting low sheet resistance (30 Ω sq-1) and improved electrode/electrolyte interface was obtained by the proposed method. When used as microsupercapacitor electrodes, this laser-induced graphene resulted in specific capacitances of 4.6 mF cm-2 (0.015 mA cm-2). Furthermore, the devices exhibit excellent cycling stability (> 10,000 cycles at 0.5 mA cm-2) and good mechanical properties. By connecting the devices in series and parallel, it was also possible to control the voltage and energy delivered by the system. Thus, paper-based LIG-MSC can be used as energy storage devices for flexible, low-cost, and portable electronics. Additionally, due to their flexible design and architecture, they can be easily adapted to other circuits and applications with different power requirements.


Assuntos
Grafite , Capacitância Elétrica , Eletrodos , Lasers
17.
Sensors (Basel) ; 22(5)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35270942

RESUMO

Compression therapy is widely used as the gold standard for management of chronic venous insufficiency and venous leg ulcers, and the amount of pressure applied during the compression therapy is crucial in supporting healing. A fibre optic pressure sensor using Fibre Bragg Gratings (FBGs) is developed in this paper to measure sub-bandage pressure whilst removing cross-sensitivity due to strain in the fibre and temperature. The interface pressure is measured by an FBG encapsulated in a polymer and housed in a textile to minimise discomfort for the patient. The repeatability of a manual fabrication process is investigated by fabricating and calibrating ten sensors. A customized calibration setup consisting of a programmable translation stage and a weighing scale gives sensitivities in the range 0.4-1.5 pm/mmHg (2.6-11.3 pm/kPa). An alternative calibration method using a rigid plastic cylinder and a blood pressure cuff is also demonstrated. Investigations are performed with the sensor under a compression bandage on a phantom leg to test the response of the sensor to changing pressures in static situations. Measurements are taken on a human subject to demonstrate changes in interface pressure under a compression bandage during motion to mimic a clinical application. These results are compared to the current gold standard medical sensor using a Bland-Altman analysis, with a median bias ranging from -4.6 to -20.4 mmHg, upper limit of agreement (LOA) from -13.5 to 2.7 mmHg and lower LOA from -32.4 to -7.7 mmHg. The sensor has the potential to be used as a training tool for nurses and can be left in situ to monitor bandage pressure during compression therapy.


Assuntos
Bandagens Compressivas , Úlcera Varicosa , Calibragem , Humanos , Temperatura , Úlcera Varicosa/terapia , Cicatrização
18.
Opt Laser Technol ; 147: None, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35241861

RESUMO

Colorimetric measurement is a versatile, low-cost method for bio-/chemical sensing and that has importance in biomedical applications. General carbon dioxide (CO2) sensors based on colorimetric change of a pH indicator report only one parameter at a time and are cross-sensitive to relative humidity (RH). This work describes a novel optical fiber sensor with a thin film on the distal end of the fiber, combining colorimetric measurement and a white light Fabry-Pérot interferometer (FPI) for the simultaneous measurement of CO2 and RH. The CO2 sensitive dye ion-pair: thymol blue and tetramethylammonium hydroxide are encapsulated inside organically modified silica forming an extrinsic FPI cavity (refractive index of 1.501 ± 0.02 and thickness of 5.83 ± 0.09 µm). The sensor reversibly responds to 0-6% CO2 and 0-90% RH with negligible cross-sensitivity and allows measurement of both parameters simultaneously. A sensitivity of ∼0.19 nm/%RH is obtained for RH measurement based on the wavelength shift of the FPI and there is a polynomial correlation between the average intensity of selected wavelengths and the concentration of CO2. The applicability of the sensor is demonstrated by measuring the CO2 and RH exhaled from human breath with a percent error of 3.1% and 2.2% respectively compared to a commercial datalogger. A simulation model is provided for the dye-encapsulated FPI sensor allowing simulation of spectra of sensors with different film thicknesses.

19.
Biotechnol Bioeng ; 118(7): 2536-2547, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33764532

RESUMO

Stable insect cell lines are emerging as an alternative to the insect cell-baculovirus expression vector system (IC-BEVS) for protein expression, benefiting from being a virus-free, nonlytic system. Still, the titers achieved are considerably lower. In this study, stable insect (Sf-9 and High Five) cells producing Gag virus-like particles (VLPs) were first adapted to grow under hypothermic culture conditions (22°C instead of standard 27°C), and then pseudotyped with a model membrane protein (influenza hemagglutinin [HA]) for expression of Gag-HA VLPs. Adaptation to lower temperature led to an increase in protein titers of up to 12-fold for p24 (as proxy for Gag-VLP) and sixfold for HA, with adapted Sf-9 cells outperforming High Five cells. Resulting Gag-HA VLPs producer Sf-9 cells were cultured to high cell densities, that is, 100 × 106 cell/ml, using perfusion (ATF® 2) in 1 L stirred-tank bioreactors. Specific p24 and HA production rates were similar to those of batch culture, enabling to increase volumetric titers by 7-8-fold without compromising the assembly of Gag-HA VLPs. Importantly, the antigen (HA) quantity in VLPs generated using stable adapted cells in perfusion was ≈5-fold higher than that from IC-BEVS, with the added benefit of being a baculovirus-free system. This study demonstrates the potential of combining stable expression in insect cells adapted to hypothermic culture conditions with perfusion for improving Gag-HA VLPs production.


Assuntos
Técnicas de Cultura de Células , Proteína do Núcleo p24 do HIV/biossíntese , Glicoproteínas de Hemaglutininação de Vírus da Influenza/biossíntese , Proteínas Recombinantes de Fusão/biossíntese , Animais , Proteína do Núcleo p24 do HIV/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Proteínas Recombinantes de Fusão/genética , Células Sf9 , Spodoptera
20.
Conserv Biol ; 35(2): 412-423, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33749051

RESUMO

The recent growth of online big data offers opportunities for rapid and inexpensive measurement of public interest. Conservation culturomics is an emerging research area that uses online data to study human-nature relationships for conservation. Methods for conservation culturomics, though promising, are still being developed and refined. We considered the potential of Wikipedia, the online encyclopedia, as a resource for conservation culturomics and outlined methods for using Wikipedia data in conservation. Wikipedia's large size, widespread use, underlying data structure, and open access to both its content and usage analytics make it well suited to conservation culturomics research. Limitations of Wikipedia data include the lack of location information associated with some metadata and limited information on the motivations of many users. Seven methodological steps to consider when using Wikipedia data in conservation include metadata selection, temporality, taxonomy, language representation, Wikipedia geography, physical and biological geography, and comparative metrics. Each of these methodological decisions can affect measures of online interest. As a case study, we explored these themes by analyzing 757 million Wikipedia page views associated with the Wikipedia pages for 10,099 species of birds across 251 Wikipedia language editions. We found that Wikipedia data have the potential to generate insight for conservation and are particularly useful for quantifying patterns of public interest at large scales.


La Wikipedia como Instrumento de Medición del Interés Público por la Biodiversidad y la Conservación Resumen El crecimiento reciente de los datos masivos en línea ofrece oportunidades para la medición rápida y asequible del interés público. La culturomia de la conservación es un área emergente de investigación que utiliza la información en línea para estudiar las relaciones entre el humano y la naturaleza y usarlas para la conservación. Los métodos de conservación basados en culturomia, aunque prometedores, todavía están siendo desarrollados y refinados. Consideramos el potencial de Wikipedia, la enciclopedia en línea, como recurso para la culturomia de la conservación y los métodos para usar sus datos en la conservación. El gran tamaño de Wikipedia, su uso extenso, estructura subyacente de datos y acceso abierto tanto a su contenido como a sus análisis de uso hacen que sea muy adecuada para usarse en la investigación de culturomia de la conservación. Las limitantes de usar la información de Wikipedia incluyen la falta de ubicación de la información asociada con algunos metadatos y la información limitada sobre los motivos de muchos usuarios. Hay siete pasos metodológicos a considerar cuando se usa la información de Wikipedia para la conservación: la selección de metadatos, temporalidad, taxonomía, representación del idioma, geografía de la Wikipedia, geografía física y biológica y medidas comparativas. Cada una de estas decisiones metodológicas puede afectar a las medidas del interés en línea. Como estudio de caso, exploramos estos temas analizando 757 millones de vistas de páginas en Wikipedia para las páginas sobre 10, 099 especies de aves a través de 251 ediciones de Wikipedia en idiomas diferentes. Encontramos que la información de Wikipedia fue particularmente útil para cuantificar los patrones de interés público a grandes escalas y tiene el potencial para generar conocimiento para la conservación.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Geografia , Humanos , Internet , Motivação
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