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Considering the increasing production of engineered nanomaterials (ENMs), new approach methodologies (NAMs) are essential for safe-by-design approaches and risk assessment. Our aim was to enhance screening strategies with a focus on reactivity-triggered toxicities. We applied in vitro tests to 10 selected benchmark ENMs in two cell models, lung epithelial A549 and differentiated THP-1 macrophage-like cells. Previously, we categorized ENMs based on surface reactivity. Here we elucidated their reactivity-triggered cytotoxicity and mode of action using the WST-1 assay (metabolic activity), LDH assay (cell membrane integrity), autophagosome detection, and proteomics. Nonreactive SiO2 NM-200 showed no significant impact on cell viability. Conversely, highly reactive CuO and ZnO (NM-110 and NM-111) disrupted cell homeostasis. Interestingly, moderately reactive TiO2 (NM-101 and NM-105) and CeO2 (NM-211 and NM-212), apparently without an adverse effect, induced autophagosome formation, evidencing autophagy as a defensive mechanism. Our improved in vitro testing strategy, combined with state-of-the-art reactivity information, screens ENMs for potential reactivity-triggered toxicity.

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In a study of antibiotic resistance in Staphylococcus aureus, specific cell wall mutants were previously generated for the peptidoglycan biosynthesis gene murF, by the insertion of an integrative plasmid. A collection of 30 independent mutants was obtained, and all harbored a variable number of copies of the inserted plasmid, arranged in tandem in the chromosome. Of the 30 mutants, only 3, F9, F20 and F26, with a lower number of plasmid copies, showed an altered peptidoglycan structure, lower resistance to ß-lactams and a different loss-of-function mutation in rho gene, that encodes a transcription termination factor. The rho mutations were found to correlate with the level of oxacillin resistance, since genetic complementation with rho gene reestablished the resistance and cell wall parental profile in F9, F20 and F26 strains. Furthermore, complementation with rho resulted in the amplification of the number of plasmid tandem repeats, suggesting that Rho enabled events of recombination that favored a rearrangement in the chromosome in the region of the impaired murF gene. Although the full mechanism of reversion of the cell wall damage was not fully elucidated, we showed that Rho is involved in the recombination process that mediates the tandem amplification of exogeneous DNA fragments inserted into the chromosome. IMPORTANCE The cell wall of bacteria, namely, peptidoglycan, is the target of several antibiotic classes such as ß-lactams. Staphylococcus aureus is well known for its capacity to adapt to antibiotic stress and develop resistance strategies, namely, to ß-lactams. In this context, the construction of cell wall mutants provides useful models to study the development of such resistance mechanisms. Here, we characterized a collection of independent mutants, impaired in the same peptidoglycan biosynthetic step, obtained through the insertion of a plasmid in the coding region of murF gene. S. aureus demonstrated the capacity to overcome the cell wall damage by amplifying the copy number of the inserted plasmid, through an undescribed mechanism that involves the Rho transcription termination factor.

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Raman spectroscopy is used in a wide variety of fields, and in a plethora of different configurations. Raman spectra of simple analytes can often be analyzed using univariate approaches and interpreted in a straightforward manner. For more complex spetral data such as time series or line profiles (1D), Raman maps (2D), or even volumes (3D), multivariate data analysis (MVDA) becomes a requirement. Even though there are some existing standards for creation, implementation, and validation of methods and models employed in industry and academics, further research and development in the field must contribute to their improvement. This review will cover, in broad terms, existing techniques as well as new developments for MVDA for Raman spectroscopic data, and in particular the use associated with instrumentation and data calibration. Chemometric models are often generated via fusion of analytical data from different sources, which enhances model discrimination and prediction abilities as compared to models derived from a single data source. For Raman spectroscopy, raw or unprocessed data is rarely ever used. Instead, spectra are usually corrected and manipulated,1 often by case-specific rather than universal methods. Calibration models can be used to characterize qualitatively and/or quantitatively samples measured with the same instrumentation that was used to create the model. However, regular validation is required to ensure that aging or incorrect maintenance of the instrument does not alter the model's predictions, particularly when applied in regulated fields such as pharmaceuticals. Furthermore, a model transfer may be required for different reasons, such as replacement or significant repair of the instrumentation. Modeling can also be used to consistently harmonize Raman spectroscopic data across several instrumental designs, accounting for variations in the resulting spectrum induced by different components. Data for Raman harmonization models should be processed in a protocolled manner, and the original data accessible to allow for model reconstruction or transfer when new data is added. Important processing steps will be the calibration of the spectral axes and instrument dependent effects, such as spectral resolution. In addition, data fusion and model transfer are essential for allowing new instrumentation to build on existing models to harmonize their own data. Ideally, an open access database would be created and maintained, for the purpose of allowing for continued harmonization of new Raman instruments using an outlined and accepted protocol.

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Over the past decades Raman spectroscopy has been extensively used both on an industrial and academic level. This has resulted in the development of numerous specialized Raman techniques and Raman active products, which in turn has led to the adoption and development of standards and norms pertaining to Raman unit's calibration, performance validation, and interoperability. Purpose of the present review is to list, classify, and engage in a comprehensive analysis of the different standards, guides, and practices relating to Raman spectroscopy. Primary aim of the review is to consider the commonalities and conflicts between these standards and norms and to identify any missing aspects. Standardization in the field of Raman spectroscopy is dominated by the work of American institutions, namely, the American Society of Testing Materials (ASTM or ASTM International), with several active standards in place pertaining to terminology, calibration, multivariate analysis, and specific applications, and the National Institute of Standards and Technology (NIST), providing numerous certified reference materials, referred to as standard reference materials. The industrial application of Raman spectroscopy is dominated by the pharmaceutical industry. As such, pharmacopoeias provide not only important information in relation to pharmaceutical-related applications of Raman spectroscopy, but also invaluable insight, into the basic principles of Raman spectroscopy and important aspects that include calibration, validation, measurement, and chemometric analysis processes, usually by referring to ASTM and NIST standards. Given the fact that Raman spectroscopy is a modern and innovative field, the standardization processes are complex and constantly evolving. Despite the seemingly high number of existing standards, the standardization landscape is incomplete and has not been modernized according to the developments in Raman spectroscopy techniques in recent years. This is evident by the lack of protocols for numerous areas as well as by the fact that some of the existing standards have not been updated to reflect the advances in the technique. Therefore, it is important for the Raman community to actively engage in and contribute to a modernization process that will result in updating existing and introducing new terms, protocols, and guides. Indeed, the development of optimized common standards would be extremely beneficial and would further foster the development and application of Raman spectroscopy techniques, most notably those of surface enhanced Raman spectroscopy and low-resolution portable analyzers.

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OBJECTIVES: to analyze the sociodemographic and clinical variables related to the adherence to self-care activities in people with diabetes mellitus type 2. METHODS: quantitative, cross-sectional study, carried out with 270 people with diabetes from December 2019 to October 2020, in São Luís, Maranhão. RESULTS: the adherence to self-care was greater when it comes to medications (Md=7.0) and foot care (Md= 6.0), but lower in regard to blood sugar testing (Md=1.0), exercise (Md=2,0), and diet (general) (Md=4.0). The variables age group (p=0.007), educational level (p=0.015), body mass index (p=0.035), complications with diabetes (p=0.009), and nutritional follow-up (p=0.000) had associations with self-care activities. CONCLUSIONS: identifying the factors related to the adherence to self-care was found to be essential to strengthen the line of care in chronic diseases and to direct educational actions, aiming to improve the quality of life of people with diabetes.

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Microplastics (MPs) are a widely recognized global problem due to their prevalence in natural environments and the food chain. However, the impact of microplastics on human microbiota and their possible biotransformation in the gastrointestinal tract have not been well reported. To evaluate the potential risks of microplastics at the digestive level, completely passing a single dose of polyethylene terephthalate (PET) through the gastrointestinal tract was simulated by combining a harmonized static model and the dynamic gastrointestinal simgi model, which recreates the different regions of the digestive tract in physiological conditions. PET MPs started several biotransformations in the gastrointestinal tract and, at the colon, appeared to be structurally different from the original particles. We report that the feeding with microplastics alters human microbial colonic community composition and hypothesize that some members of the colonic microbiota could adhere to MPs surface promoting the formation of biofilms. The work presented here indicates that microplastics are indeed capable of digestive-level health effects. Considering this evidence and the increasing exposure to microplastics in consumer foods and beverages, the impact of plastics on the functionality of the gut microbiome and their potential biodegradation through digestion and intestinal bacteria merits critical investigation.

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ABSTRACT Objectives: to analyze the sociodemographic and clinical variables related to the adherence to self-care activities in people with diabetes mellitus type 2. Methods: quantitative, cross-sectional study, carried out with 270 people with diabetes from December 2019 to October 2020, in São Luís, Maranhão. Results: the adherence to self-care was greater when it comes to medications (Md=7.0) and foot care (Md= 6.0), but lower in regard to blood sugar testing (Md=1.0), exercise (Md=2,0), and diet (general) (Md=4.0). The variables age group (p=0.007), educational level (p=0.015), body mass index (p=0.035), complications with diabetes (p=0.009), and nutritional follow-up (p=0.000) had associations with self-care activities. Conclusions: identifying the factors related to the adherence to self-care was found to be essential to strengthen the line of care in chronic diseases and to direct educational actions, aiming to improve the quality of life of people with diabetes.

RESUMEN Objetivos: analizar variables sociodemográficas y clínicas relacionadas a la adhesión a actividades de autocuidado en personas con diabetes mellitus tipo 2. Métodos: estudio cuantitativo, transversal, realizado con 270 personas con diabetes, entre diciembre de 2019 y octubre de 2020, en São Luís, Maranhão. Resultados: hubo adhesión más favorable al autocuidado cuanto al uso del medicamento (Md=7,0) y cuidados con los pies (Md= 6,0) y adhesión menos deseable cuanto al monitoreo de la glucemia (Md=1,0), práctica de actividad física (Md=2,0) y alimentación general (Md=4,0). Las variables franja etaria (p=0,007), escolaridad (p=0,015), índice de masa corporal (p=0,035), complicación del diabetes (p=0,009) y acompañamiento nutricional (p=0,000) presentaron relación con las actividades de autocuidado. Conclusiones: la identificación de factores relacionados a la adhesión al autocuidado se mostró esencial para el fortalecimiento de la línea de cuidados en enfermedades crónicas y direccionamiento de acciones educativas, visando mejorar la calidad de vida de personas con diabetes.

RESUMO Objetivos: analisar as variáveis sociodemográficas e clínicas relacionadas com a adesão às atividades de autocuidado em pessoas com diabetes mellitus tipo 2. Métodos: estudo quantitativo, transversal, realizado com 270 pessoas com diabetes, entre dezembro de 2019 e outubro de 2020, em São Luís, Maranhão. Resultados: houve adesão mais favorável ao autocuidado quanto ao uso do medicamento (Md=7,0) e cuidados com os pés (Md= 6,0) e adesão menos desejável quanto à monitorização da glicemia (Md=1,0), prática da atividade física (Md=2,0) e alimentação geral (Md=4,0). As variáveis faixa etária (p=0,007), escolaridade (p=0,015), índice de massa corporal (p=0,035), complicação do diabetes (p=0,009) e acompanhamento nutricional (p=0,000) apresentaram associação com as atividades de autocuidado. Conclusões: a identificação dos fatores relacionados com a adesão ao autocuidado mostrou-se essencial para o fortalecimento da linha de cuidados em doenças crônicas e direcionamento das ações educativas, visando melhorar a qualidade de vida das pessoas com diabetes.

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A unique 1D nanostructure of Pt@CeO2-BDC was prepared from Pt@CeBDC MOF. The Pt@CeO2-BDC was rich in oxygen vacancies (i.e., XPS Oß/(Oα + Oß) = 39.4%), and on the catalyst, the 2 nm Pt clusters were uniformly deposited on the 1D mesoporous polycrystalline CeO2. Toluene oxidation was conducted in a spectroscopic operando Raman-online FTIR reactor to elucidate the reaction mechanism and establish the structure-activity relationship. The reaction proceeds as follows: (I) adsorption of toluene as benzoate intermediates on Pt@CeO2-BDC at low temperature by reaction with surface peroxide species; (II) reaction activation and ring-opening involving lattice oxygen with a concomitant change in defect densities indicative of surface rearrangement; (III) complete oxidation to CO2 and H2O by lattice oxygen and reoxidation of the reduced ceria with consumption of adsorbed oxygen species. The Pt clusters, which mainly exist as Pt2+ with minor amounts of Pt0 and Pt4+ on the surface, facilitated the adsorption and reaction activation. The Pt-CeO2 interface generates reduced ceria sites forming nearby adsorbed peroxide at low temperature that oxidize toluene into benzoate species by a Langmuir-Hinshelwood mechanism. As the reaction temperature increases, the role of lattice oxygen becomes important, producing CO2 and H2O mainly by the Mars-van Krevelen mechanism.

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Resumo Objetivo Analisar a oferta dos cursos de graduação em saúde na modalidade de Ensino a Distância no Brasil, destacando suas principais características para Enfermagem. Método Estudo transversal baseado em dados on line de cursos de graduação em saúde a distância, criados entre 2005 e 2020. Para doze graduações em saúde, destacaram-se características da criação e distribuição do ensino a distância, enfatizando-se a situação da Enfermagem. Realizaram-se testes de significância estatística (α=5%) e mapa. Resultados Verificaram-se 431 cursos de graduação em saúde, sendo a maioria deles criados entre 2017 e 2020 (≥61,4%). Para Enfermagem, o período de maior criação foi anterior (entre 2013 e 2016; 72,7%) (p=0,001). Todos os cursos eram vinculados a instituições privadas, que ofertavam 82.000 vagas, distribuídas em 1.363 Polos por todos os estados. Verificou-se predomínio em São Paulo (23,9%) e nas cidades localizadas no interior dos estados (64,3%) (p=0,001). Conclusão e implicações para prática Houve aumento significativo de cursos de graduação em saúde no ensino a distância no Brasil. Para Enfermagem, estes se caracterizaram por oferta privada e localizada no interior dos estados. Contudo, a distribuição regional ainda é desigual, concentrando Polos nas regiões mais ricas e centrais do país, e longe das áreas com maiores necessidades de saúde.

Resumen Objetivo Analizar la oferta de estudios superiores en salud bajo la modalidad de Educación a Distancia en Brasil, destacando sus principales características para Enfermería. Método Estudio transversal a partir de datos en línea de las carreras de grado en salud a distancia, creadas entre 2005 y 2020. Para doce titulaciones de salud se destacaron características de la creación y distribución de la educación a distancia, destacando la situación de Enfermería. Se realizaron pruebas de significación estadística (α = 5%) y mapa. Resultados Se detectaron 431 carreras de grado en salud, la mayoría de las cuales se crearon entre 2017 y 2020 (≥61,4%). Para Enfermería, el período de mayor creación fue anterior (entre 2013 y 2016; 72,7%) (p = 0,001). Todos los cursos estuvieron vinculados a instituciones privadas, que ofrecieron 82.000 plazas, distribuidas en 1.363 centros en todos los estados. Se registró predominio de cursos en São Paulo (23,9%) y en ciudades del interior de los estados (64,3%) (p = 0,001). Conclusión e implicaciones para la práctica Se advierte un aumento significativo en los cursos de pregrado en salud en educación a distancia en Brasil. Para Enfermería, estos se caracterizaron por una oferta privada ubicada en el interior de los estados. Sin embargo, la distribución regional sigue siendo desigual, concentrada en las regiones más ricas y céntricas del país, y lejos de las áreas con mayores necesidades de salud.

Abstract Objective To analyze the offer of undergraduate health courses in the Distance Learning modality in Brazil, highlighting its main characteristics for Nursing. Method This is a cross-sectional study based on distance health undergraduate courses online data, created between 2005 and 2020. For twelve health degrees, characteristics of the creation and distribution of distance learning were highlighted, emphasizing Nursing courses. Statistical significance tests (α = 5%) and mapping were performed. Results There were 43 undergraduate courses in health, most of which were created between 2017 and 2020 (≥61.4%). For Nursing, most courses were created in earlier years (2013 and 2016; 72.7%) (p = 0.001). The courses were linked to private institutions, which offered 82,000 seats and are distributed in 1,363 hubs across all states. Courses predominated in São Paulo (23.9%) and non-capital cities (64.3%) (p = 0.001). Conclusion and implications for the practice There has been a significant increase in distance education in Brazil's undergraduate health courses. For Nursing, the courses were characterized by private offers located in non-capital cities. However, the regional distribution is still uneven, concentrating hubs in the country's richest and most central regions and away from areas with the greatest health needs.

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Raman and transmission FTIR spectroscopic techniques have been coupled in a new homemade reactor-cell designed in a joint CSIC-LCS collaboration. The setup is easily adapted to any FTIR and fiber-coupled Raman spectrometers and gas analysis techniques. It allows for simultaneous operando FTIR and Raman spectroscopic measurement, which provide complementary characterization of adsorbed species, reaction intermediates, and structural properties of the catalyst. This system was validated with the study of vanadium-based catalysts during propane oxydehydrogenation (ODH). The combined use of both spectroscopies with gas analysis techniques to measure the activity contributes to the understanding of propane ODH and the identification of the role of different oxygen species bound to vanadium sites. For example, the simultaneous characterization of the catalyst under the same conditions by IR and Raman confirms that the V═O mode has the same frequency in both spectroscopies and that bridging oxygen sites (V-O-V, V-O-Zr) present higher activity than terminal V═O bonds. These results demonstrate the high potential of the new simultaneous transmission IR-Raman operando rig to correlate the activity and the structure of catalysts, thus assisting the rational design of catalytic processes.

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Glutamate amidation, a secondary modification of the peptidoglycan, was first identified in Staphylococcus aureus It is catalyzed by the protein products of the murT and gatD genes, which are conserved and colocalized in the genomes of most sequenced Gram-positive bacterial species. The MurT-GatD complex is required for cell viability, full resistance to ß-lactam antibiotics, and resistance to human lysozyme and is recognized as an attractive target for new antimicrobials. Great effort has been invested in the study of this step, culminating recently in three independent reports addressing the structural elucidation of the MurT-GatD complex. In this work, we demonstrate through the use of nonstructural approaches the critical and multiple roles of the C-terminal domain of MurT, annotated as DUF1727, in the MurT-GatD enzymatic complex. This domain provides the physical link between the two enzymatic activities and is essential for the amidation reaction. Copurification of recombinant MurT and GatD proteins and bacterial two-hybrid assays support the observation that the MurT-GatD interaction occurs through this domain. Most importantly, we provide in vivo evidence of the effect of substitutions at specific residues in DUF1727 on cell wall peptidoglycan amidation and on the phenotypes of oxacillin resistance and bacterial growth.

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Although several therapeutic approaches are available for wound and burn treatment and much progress has been made in this area, room for improvement still exists, driven by the urgent need of better strategies to accelerate wound healing and recovery, mostly for cases of severe burned patients. Bacterial cellulose (BC) is a biopolymer produced by bacteria with several advantages over vegetal cellulose, such as purity, high porosity, permeability to liquid and gases, elevated water uptake capacity and mechanical robustness. Besides its biocompatibility, BC can be modified in order to acquire antibacterial response and possible local drug delivery features. Due to its intrinsic versatility, BC is the perfect example of a biotechnological response to a clinical problem. In this review, we assess the BC main features and emphasis is given to a specific biomedical application: wound dressings. The production process and the physical-chemical properties that entitle this material to be used as wound dressing namely for burn healing are highlighted. An overview of the most common BC composites and their enhanced properties, in particular physical and biological, is provided, including the different production processes. A particular focus is given to the biochemistry and genetic manipulation of BC. A summary of the current marketed BC-based wound dressing products is presented, and finally, future perspectives for the usage of BC as wound dressing are foreseen.

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The photocatalytic elimination of microorganisms from indoor air in realistic conditions and the feasibility of simultaneous elimination of chemical contaminants have been studied at laboratory scale. Transparent polymeric monoliths have been coated with sol-gel TiO(2) films and used as photocatalyst to treat real indoor air in a laboratory-scale single-step annular photocatalytic reactor. The analytical techniques used to characterize the air quality and analyze the results of the photocatalytic tests were: colony counting, microscopy and PCR with subsequent sequencing for microbial quantification and identification; automated thermal desorption coupled to gas chromatography with mass spectrometry detection for chemical analysis. The first experiments performed proved that photocatalysis based on UVA-irradiated TiO(2) for the reduction of the concentration of bacteria in the air could compete with the conventional photolytic treatment with UVC radiation, more expensive and hazardous. Simultaneously to the disinfection, the concentration of volatile organic compounds was greatly reduced, which adds value to this technology for real applications. The fungal colony number was not apparently modified.

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Hybrid structured photocatalysts based on sepiolite, an adsorbent, and TiO2 were prepared by extrusion of ceramic dough and conformed as plates. The influence of the photocatalyst configuration was studied either by including TiO2 in the extrusion process (incorporated materials) or by coating the sepiolite plates with a TiO2 film (coated materials). The influence of the OH- surface concentration in the photocatalytic performance was studied by treating the ceramic plates at different temperatures. The samples were characterized by N2 adsorption-desorption, MIP, SEM, XRD, and UV-vis-NIR spectroscopy and tested in the photocatalytic degradation of trichloroethylene (TCE) as a target VOC molecule. Most of the catalysts presented high photoactivity, but considerable differences were observed when the CO2 selectivity was analyzed. The results demonstrate that there is a significant effect of the catalyst configuration on the selectivity of the process. An intimate contact between the sepiolite fibers and TiO2 particles for incorporated materials with a corncob-like structure favored the migration of nondesirable reaction products such as COCl2 and dichloroacetyl chloride (DCAC) to the adsorbent, reacting with OH- groups of the adsorbent and favoring the TCE mimeralization.

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