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1.
Appl Spectrosc ; 78(10): 1028-1042, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39094004

RESUMO

The aim of this work was the development and morphological/chemical, spectroscopic, and structural characterization of titanium dioxide, niobium pentoxide, and titanium:niobium (Ti:Nb) oxides, as well as materials modified with ruthenium (Ru) with the purpose of providing improvement in photoactivation capacity with visible sunlight radiation. The new materials synthesized using the sol-gel methodology were characterized using the following techniques: scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), photoacoustic spectroscopy (PAS), and X-ray diffraction (XRD). The SEM-EDS analyses showed the high purity of the bases, and the modified samples showed the adsorption of ruthenium on the surface with the crystals' formation and visible agglomerates for higher calcination temperature. The nondestructive characterization of PAS in the ultraviolet visible region suggested that increasing calcination temperature promoted changes in chemical structures and an apparent decrease in gap energy. The separation of superimposed absorption bands referring to charge transfers from the ligand to the metal and the nanodomains of the transition metals suggested the possible absorption centers present at the absorption threshold of the analyzed oxides. Through the XRD analysis, the formation of stable phases such as T-Nb16.8O42, o-Nb12O29, and rutile was observed at a lower temperature level, suggesting pore induction and an increase in surface area for the oxides studied, at a calcination temperature below that expected by the related literature. In addition, the synthesis with a higher temperature level altered the previously existing morphologies of the Ti:Nb, base and modified with Ru, forming the new mixed crystallographic phases Ti2Nb10O29 and TiNb2O7, respectively. As several semiconductor oxide applications aim to reduce costs with photoexcitation under visible light, the modified Ti:Ru oxide calcined at a temperature of 800 °C and synthesized according to the sol-gel methodology used in this work is suggested as the optimum preparation point. This study presented the formation of a stable crystallographic phase (rutile), a significant decrease in gap energy (2.01 eV), and a visible absorption threshold (620 nm).

2.
Front Psychol ; 15: 1380935, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39118842

RESUMO

The purpose of this study is to determine if there is a positive relationship between full-range leadership and employees' effort, efficiency, and satisfaction. A questionnaire was administered to 577 executives from Colombian companies, and the data was analyzed using a partial least squares structural equation modeling (PLS-SEM) approach. The results show that both transformational and transactional leadership have a direct and significant impact on extra effort, effectiveness, and satisfaction, with transformational leadership having the greatest impact on these factors. Conversely, passive-avoidant leadership has negative effects on these three constructs. This study validates the effectiveness of the MLQ 5X in a South American country, a geographical region where such studies are in their early stages. Finally, the whole range of leadership styles-transformational, transactional, and passive-avoidant-is looked at. These styles are seen as second-order constructs that challenge latent multidimensional models as they emerge.

3.
Polymers (Basel) ; 16(14)2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39065380

RESUMO

The use of mineral reinforcements in polymer matrix composites has emerged as an alternative for sustainable production, reducing waste and enhancing the physical and mechanical properties of these materials. This study investigated the impact of the melt flow index (MFI) of HDPE and the particle size of two mineral reinforcements, Bahia Beige (BB) and Rio Grande do Norte Limestone (CRN), on the composites. All composites were processed via extrusion, followed by injection, with the addition of 30 wt.% reinforcement. Chemical analyses revealed similar compositions with high CaO content for both minerals, while X-ray diffraction (XRD) identified predominantly calcite, dolomite, and quartz phases. Variations in the MFI, reinforcement type, and particle size showed a minimal influence on composite properties, supported by robust statistical analyses that found no significant differences between groups. Morphological analysis indicated that composites with lower MFI exhibited less porous structures, whereas larger particles of BB and CRN formed clusters, affecting impact resistance, which was attributed to poor interfacial adhesion.

4.
Nutrients ; 16(13)2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38999844

RESUMO

The COVID-19 pandemic exacerbated various determinants of mental disorders. Several behavioral changes were observed given this increase, including harmful health consequences, such as excessive consumption of ultra-processed foods (UPFs). To assess this relationship, we investigated the meditational role of symptoms of mental disorders (anxiety and depression) in the association between stress resulting from social distancing during the COVID-19 pandemic and the consumption of UPFs in 3884 Brazilian public employees in a supplementary study of the ELSA-Brasil study. Structural equation models (SEMs) were estimated to assess the direct and indirect effects mediated by symptoms of mental disorders. The results suggested a significant and positive mediational effect of the symptoms of mental disorders on the association between the stress resulting from social distancing and the consumption of UPFs. These findings contribute to informing the need for policies and early interventions in potentially stressful situations, with a focus on the promotion of mental health, and may thus help prevent or reduce the consumption of unhealthy foods.


Assuntos
COVID-19 , Fast Foods , Distanciamento Físico , SARS-CoV-2 , Estresse Psicológico , Humanos , COVID-19/psicologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , Brasil/epidemiologia , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Depressão/epidemiologia , Ansiedade , Transtornos Mentais/epidemiologia , Transtornos Mentais/etiologia , Saúde Mental/estatística & dados numéricos , Pandemias , Alimento Processado
5.
Zookeys ; 1205: 169-189, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38957218

RESUMO

Diapausing embryos encased within cladoceran ephippia result from sexual reproduction and increase genetic diversity. They are also important means by which species bypass harsh environmental conditions and disperse in space and time. Once released, ephippia usually sink to the benthos and remain there until hatching. Using the Sars' method (incubating sediments to identify cladoceran hatchlings), ephippial egg bank biodiversity can be evaluated. Yet, even when samples are incubated under a variety of conditions, it is not possible to warrant that all have hatched. Few keys are available that facilitate the identification of cladocerans by using only ephippial morphology. Our goal was to analyze some cladoceran ephippia from Mexico, to develop a means to identify them using easily recognizable characteristics. Ephippia of 23 cladoceran species from waters in Aguascalientes (México) in 11 genera (Alona, Biapertura, Ceriodaphnia, Chydorus, Daphnia, Dunhevedia, Ilyocryptus, Macrothrix, Moina, Pleuroxus, and Simocephalus) were analyzed. In our analysis six morphological features were selected that permitted the identification of ephippia to species(-group) level. The results demonstrate that with a proper catalog of features, some ephippia can be identified.

6.
Int. j. morphol ; 42(3): 698-708, jun. 2024. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1564638

RESUMO

SUMMARY: Tissue engineering aims to fabricate a scaffold that exhibits a suitable surface topography for a desired cellular response. Therefore, a study analyzing the characteristics of bone grafts is important for future research directions. This work aims to analyze the physical-chemical characteristics of commercially available bone grafts of human and bovine origin for dental use, using morphological analysis of the surface and chemical composition by variable pressure scanning electron microscope (VP-SEM) and energy-dispersive x-ray (EDX) spectrometry. In addition, pore diameter and surface area were analyzed by degassing method using a porosimeter, and particle size by laser diffraction. The analyzed allograft and xenograft particles differ in morphological characteristics and chemical composition. The allograft particles present a cuboidal and prismatic geometric morphology with angled edges and the absence of macropores. On the contrary, the xenograft particles present an irregular morphology with macropores in their structure. There is a statistically significant difference in C, P, and Ca between the xenograft and allografts (p < 0,05). The analyzed composition of allografts showed mainly the presence of C and O. In contrast, the composition of the xenograft was mainly Ca. These differences could influence the osteogenic properties of allografts and xenografts. This analysis provides basic information to understand the physicochemical properties of allografts and xenografts that facilitate cell-graft interaction.


La ingeniería de tejidos tiene como objetivo fabricar un andamio que muestre una topografía de superficie adecuada para una respuesta celular deseada. Por tanto, un estudio que analice las características de los injertos óseos es importante para futuros enfoques de investigación. Este trabajo tiene como objetivo analizar las características físico-químicas de injertos óseos de origen humano y bovino disponibles comercialmente para uso odontológico, mediante análisis morfológico de la superficie y composición química mediante microscopio electrónico de barrido de presión variable (VP-SEM) y x-dispersivo de energía. espectrometría de rayos (EDX). Además, el diámetro de los poros y el área superficial se analizaron mediante el método de desgasificación utilizando un porosímetro y el tamaño de las partículas mediante difracción láser. Las partículas de aloinjerto y xenoinjerto analizadas difieren en características morfológicas y composición química. Las partículas del aloinjerto presentan una morfología geométrica cúbica y prismática con bordes angulados y ausencia de macroporos. Por el contrario, las partículas de xenoinjerto presentan una morfología irregular con macroporos en su estructura. Existe una diferencia estadísticamente significativa en C, P y Ca entre el xenoinjerto y los aloinjertos (p < 0,05). La composición analizada de los aloinjertos mostró principalmente la presencia de C y O. Por el contrario, la composición del xenoinjerto fue principalmente Ca. Estas diferencias podrían influir en las propiedades osteogénicas de los aloinjertos y xenoinjertos. Este análisis proporciona información básica para comprender las propiedades fisicoquímicas de aloinjertos y xenoinjertos que facilitan la interacción célula-injerto.


Assuntos
Humanos , Animais , Bovinos , Aloenxertos/anatomia & histologia , Aloenxertos/química , Espectrometria por Raios X , Regeneração Óssea , Microscopia Eletrônica de Varredura , Porosidade , Transplante Ósseo , Xenoenxertos/anatomia & histologia , Xenoenxertos/química
7.
Materials (Basel) ; 17(10)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38793322

RESUMO

The change in the corrosion activities of SS304 and the carbon steel A36 were studied during their exposure for 30 days to hybrid pumice-Portland cement extract (CE), to simulate the concrete-pore environment. The ionic composition and the initial pH (12.99) of the CE were influenced by the reduction of Portland cement (PC) content, volcanic pumice oxides and alkaline activators. Because of the air CO2 dissolution, the pH decreased and maintained a constant value ≈ 9.10 (established dynamic ionic equilibrium). The CE promoted the passivation of both steels and their free corrosion potential (OCP) reached positive values. On the surfaces, Fe and Cr oxides were formed, according to the nature of the steel. Over the time of exposure, the presence of chloride ions in the pumice caused a localized pitting attack, and for carbon steel, this fact may indicate an intermediate risk of corrosion. The chloride effect was retarded by the accumulation of SO42- ions at the steel surfaces. Based on electrochemical impedance (EIS), the polarization resistance (Rp) and the thickness of the passive layers were calculated. Their values were compared with those previously reported for the steels exposed to CEs of Portland and supersulfated cements, and the hybrid cement was considered as a PC "green" alternative.

8.
Zookeys ; 1198: 1-15, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38693971

RESUMO

Hanseniellachilensis is the only myriapod of the class Symphyla known from Chile. This garden centipede, or pseudocentipede, was described more than 120 years ago based on morphologically incomplete specimens collected in central Chile, a well-known biodiversity hotspot. In this study, we redescribe this species based on morphologically complete specimens collected near the type locality using scanning electron microscope images. Our study provides the description of diagnostic characters hitherto unknown in this species such as macrochaetae of the tergites and spinnerets of the cerci. We also include a new record from central Chile and discuss the presumed presence of this species in Argentina and Madagascar.

9.
Aust Endod J ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773855

RESUMO

To use scanning electron microscopy and energy dispersive X-ray spectroscopy to evaluate the metallurgical-chemical changes of WaveOne Gold (WOG) and R-Motion (RM), after multiple uses. The instruments were divided into groups (n = 8): WOG and RM-control groups, new instruments; WOG1 and RM1; WOG2 and RM2; WOG3 and RM3 after instrumentation of 1, 2 or 3 molars, respectively. Burrs occurred mainly in the control group and after the first use. The RM files were found to have a higher nickel content, which increased during reuse, and a decrease in oxygen content with increasing reuse, in addition to calcium impregnation, which occurred in greater amounts in the corrosion areas in the WOG files. The presence of topographic and chemical changes was demonstrated, indicating that caution should be taken when reusing endodontic instruments to avoid fractures.

10.
Odovtos (En línea) ; 26(1): 86-99, Jan.-Apr. 2024. tab, graf
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1558621

RESUMO

Abstract To assess the effect of different whitening toothpastes on enamel surface morphology, chemical profile and their whitening efficiency. Sixty teeth were divided into 5 groups (12 teeth/group); Gp I: brushed with no toothpaste. Gp II: brushed with Pearl-based toothpaste. Gp III: brushed with Charcoal- based toothpaste. Gp IV: brushed with Alumina-based toothpaste. Gp V: brushed with salt and lemon- based toothpaste. Each tooth was brushed with a bean sized toothpaste wetted with distilled water twice daily by using standard electronic toothbrush for four weeks. Enamel surface morphology, chemical profile and color of each tooth were investigated. Chemical profile results and color measurements were analyzed statistically. Gp I revealed normal enamel surface morphology and chemical profile. Gp II and Gp III demonstrated surface morphology close to Gp I with insignificant reduction in mineral content. Gp IV showed obvious shallowing of perikymata ridges, exposure of fish-scale appearance, with pits and depressions, alongside to the significant reduction in mineral content. Gp V presented the most enamel surface alteration with widening of prism sheath and depressions all over the surface, besides the highest significant reduction in mineral content. Gp V, followed by Gp IV, demonstrated the highest color and whiteness changes, followed by Gp III, then Gp II, while the lowest value was in Gp I. Salt & lemon-based toothpaste, followed by Alumina-based, exerted the most considerable changes in the morphology and chemical profile of the enamel surface, beside to the higher whitening effects on teeth than the others.


Resumen El objetivo del presente estudio fue evaluar el efecto de diferentes pastas dentales blanqueadoras sobre la morfología y el perfil químico de la superficie del esmalte y su eficacia blanqueadora. Sesenta dientes se dividieron en 5 grupos (12 dientes/grupo); Grupo I: cepillado sin pasta de dientes. Grupo II: cepillado con pasta de dientes a base de perlas. Grupo III: cepillado con pasta de dientes a base de carbón. Grupo IV: cepillado con pasta de dientes a base de Alúmina. Grupo V: cepillado con sal y pasta de dientes a base de limón. Cada diente se cepilló con una pasta de dientes del tamaño de un frijol humedecida con agua destilada dos veces al día utilizando un cepillo de dientes electrónico estándar durante cuatro semanas. Se investigaron la morfología de la superficie del esmalte, el perfil químico y el color de cada diente. Los resultados del perfil químico y las mediciones de color se analizaron estadísticamente. El Grupo I reveló una morfología de la superficie del esmalte y un perfil químico normales. Los Grupos II y III demostraron una morfología de superficie cercana a la del Grupo I con una reducción insignificante en el contenido mineral. El grupo IV mostró una evidente reducción de las crestas perikymatas, exposición de apariencia de escamas de pez, con hoyos y depresiones, junto con una reducción significativa en el contenido mineral. El grupo V presentó la mayor alteración de la superficie del esmalte con ensanchamiento de la vaina del prisma y depresiones en toda la superficie, además de una significativa reducción en el contenido mineral. El grupo V, seguido del grupo IV, demostró los mayores cambios de color y blancura, seguido del grupo III, luego el grupo II, mientras que el valor más bajo se presentó en el grupo I. Las pastas dentales a base de sal y limón, seguidas de las de alúmina, ejercieron los cambios más considerables en la morfología y el perfil químico de la superficie del esmalte, además de tener mayores efectos blanqueadores sobre los dientes que las demás.


Assuntos
Clareamento Dental/métodos , Cremes Dentais/análise , Esmalte Dentário , Técnicas In Vitro , Costa Rica
11.
Materials (Basel) ; 17(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38612191

RESUMO

Corrosion processes at cut edges of galvanized steels proceed as highly localized electrochemical reactions between the exposed bulk steel matrix and the protective thin metallic coating of a more electrochemically active material. Scanning microelectrochemical techniques can thus provide the spatially resolved information needed to assess the corrosion initiation and propagation phenomena, yet most methods scan cut edge sections as embedded in insulating resin to achieve a flat surface for scanning purposes. In this work, the galvanized coatings on both sides of the material were concomitantly exposed to simulated acid rain while characterizing the cut edge response using SECM and SVET techniques, thereby maintaining the coupled effects through the exposure of the whole system as rather realistic operation conditions. The cut edges were shown to strongly promote oxygen consumption and subsequent alkalization to pH 10-11 over the iron, while diffusion phenomena eventually yielded the complete depletion of oxygen and pH neutralization of the nearby electrolyte. In addition, the cathodic activation of the exposed iron was intensified with a thinner coating despite the lower presence of sacrificial anode, and preferential sites of the attack in the corners revealed highly localized acidification below pH 4, which sustained hydrogen evolution at spots of the steel-coating interface.

12.
Polymers (Basel) ; 16(8)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38675080

RESUMO

Nitrile gloves have become a significant environmental pollutant after the COVID-19 pandemic due to their single-use design. This study examines the capability of P. aeruginosa to use nitrile gloves as its sole carbon energy source. Biodegradation was determined by P. aeruginosa adapting to increasing nitrile glove concentrations at 1%, 3%, and 5% (w/v). The growth kinetics of P. aeruginosa were evaluated, as well as the polymer weight loss. Topographic changes on the glove surfaces were examined using SEM, and FT-IR was used to evaluate the biodegradation products of the nitrile gloves. Following the establishment of a biofilm on the glove surface, the nitrile toxicity was minimized via biodegradation. The result of the average weight loss of nitrile gloves was 2.25%. FT-IR analysis revealed the presence of aldehydes and aliphatic amines associated with biodegradation. SEM showed P. aeruginosa immersed in the EPS matrix, causing the formation of cracks, scales, protrusions, and the presence of semi-spherical particles. We conclude that P. aeruginosa has the capability to use nitrile gloves as its sole carbon source, even up to 5%, through biofilm formation, demonstrating the potential of P. aeruginosa for the degradation of nitrile gloves.

13.
Heliyon ; 10(5): e26520, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38434298

RESUMO

Computational cell segmentation is a vital area of research, particularly in the analysis of images of cancer cells. The use of cell lines, such as the widely utilized HeLa cell line, is crucial for studying cancer. While deep learning algorithms have been commonly employed for cell segmentation, their resource and data requirements can be impractical for many laboratories. In contrast, image processing algorithms provide a promising alternative due to their effectiveness and minimal resource demands. This article presents the development of an algorithm utilizing digital image processing to segment the nucleus and shape of HeLa cells. The research aims to segment the cell shape in the image center and accurately identify the nucleus. The study uses and processes 300 images obtained from Serial Block-Face Scanning Electron Microscopy (SBF-SEM). For cell segmentation, the morphological operation of erosion was used to separate the cells, and through distance calculation, the cell located at the center of the image was selected. Subsequently, the eroded shape was employed to restore the original cell shape. The nucleus segmentation uses parameters such as distances and sizes, along with the implementation of verification stages to ensure accurate detection. The accuracy of the algorithm is demonstrated by comparing it with another algorithm meeting the same conditions, using four segmentation similarity metrics. The evaluation results rank the proposed algorithm as the superior choice, highlighting significant outcomes. The algorithm developed represents a crucial initial step towards more accurate disease analysis. In addition, it enables the measurement of shapes and the identification of morphological alterations, damages, and changes in organelles within the cell, which can be vital for diagnostic purposes.

14.
Violence Against Women ; : 10778012241228289, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38304980

RESUMO

Despite efforts within Ecuador to combat violence against women (VAW), the country still claims some of the highest rates of violence in the Americas. In this study, we complete a cultural visual analysis of anti-VAW public art in a small Ecuadorian city. Visual data is examined and interpreted by way of the social-ecological model (SEM). Specifically, our analysis considers how murals engage with the depiction of (a) VAW, (b) agentic responses to VAW, and (c) the different layers of the SEM. Our analysis identifies four specific strategies for constructing public art messaging to help achieve freedom from VAW.

15.
Sci Total Environ ; 914: 170026, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38218486

RESUMO

Estuarine coastal water and sediments collected from multiple locations within the middle Río de la Plata (RDLP) estuary were analyzed in order to identify the presence of microplastics (MPs, <5 mm) and mesoplastics (MePs, 5-25 mm) in one of the most significant estuaries in the Southwestern Atlantic. The present study represents one of the first researches to survey MPs and MePs contamination in key stations at RDLP estuary. Average concentrations of 14.17 ± 5.50 MPs/L and 10.00 MePs/L were detected in water samples, while 547.83 ± 620.06 MPs/kg (dry weight) and 74.23 ± 47.29 MePs/kg d.w. were recorded in sediments. The greatest abundances were observed in the more anthropized areas, near urban settlements. Fibers were the most conspicuous plastic items in water and sediments, followed by fragments. On the other hand, surface sediments, and 50 cm and 100 cm-depth sediments also presented MPs and MePs indicating they could serve as a stratigraphic indicator for recently formed sediments. The main polymer type identified were acrylic fibers, followed by polypropylene (PP) and polyethylene terephthalate (PET). Besides, SEM-EDX detected the presence of Si, Fe, Ti, Al and Cl onto the plastics' surface. These elements may serve as additives to enhance the plastics' properties, such as in the case of Ti, or they could originate from the environment, like biogenic Si or Fe, and Al possibly as a component of the suspended particles or sediments adhered to the micro or meso plastics. Finally, the results of the present study showed that MPs and MePs are commonly found in waters and also tend to be trapped in sediments of the RDLP estuary supporting the assertion that these areas play a substantial role in influencing the transport, dispersion, and buildup of MPs in estuarine regions.

16.
Polymers (Basel) ; 16(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38276707

RESUMO

The present work reports on an empirical mathematical expression for predicting the digital porosity (DP) of electrospun nanofiber veils, employing emulsions of poly(vinyl alcohol) (PVOH) and olive and orange oils. The electrospun nanofibers were analyzed by scanning electron microscopy (SEM), observing orientation and digital porosity (DP) in the electrospun veils. To determine the DP of the veils, the SEM micrographs were transformed into a binary system, and then the threshold was established, and the nanofiber solid surfaces were emphasized. The relationship between the experimental results and those obtained with the empirical mathematical expression displayed a correlation coefficient (R2) of 0.97 by employing threshold II. The mathematical expression took into account experimental variables such as the nanofiber humidity and emulsion conductivity prior to electrospinning, in addition to the corresponding operation conditions. The results produced with the proposed expression showed that the prediction of the DP of the electrospun veils was feasible with the considered thresholds.

17.
Braz J Microbiol ; 55(1): 343-355, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38066229

RESUMO

Sulfonamide derivatives have numerous pharmaceutical applications having antiviral, antibacterial, antifungal, antimalarial, anticancer, and antidepressant activities. The structural flexibility of sulfonamide derivatives makes them an excellent candidate for the development of new multi-target agents, although long-time exposure to sulfonamide drugs results in many toxic impacts on human health. However, sulfonamides may be functionalized for developing less toxic and more competent drugs. In this work, sulfonamides including Sulfapyridine (a), Sulfathiazole (b), Sulfamethoxazole (c), and Sulfamerazine (d) are used to synthesize Schiff bases of 7-hydroxy-4-methyl-2-oxo-2H-chromene-8-carbalde-hyde (1a-1d). The synthesized compounds were spectroscopically characterized and tested against hospital isolates of three Gram-positive (Methicillin-resistant Staphylococcus aureus PH217, Ampicillin-resistant Coagulase-negative Staphylococcus aureus, multidrug-resistant (MDR) Enterococcus faecalis PH007R) and two Gram-negative bacteria (multidrug-resistant Escherichia coli, and Salmonella enterica serovar Typhi), compared to the quality control strains from ATCC (S. aureus 29213, E. faecalis 25922, E. coli 29212) and MTCC (S. Typhi 734). Two of the four Schiff bases 1a and 1b are found to be more active than their counterpart 1c and 1d; while 1a have showed significant activity by inhibiting MRSA PH217 and MDR isolates of E. coli at the minimum inhibitory concentration (MIC) of 150 µg/mL and 128 µg/mL with MBC of 1024 µg/mL, respectively. On the other hand, the MIC of 1b was 150 µg/mL against both S. aureus ATCC 29213 and Salmonella Typhi MTCC 734, compared to the control antibiotics Ampicillin and Gentamycin. Scanning electron microscopy demonstrated the altered surface structure of bacterial cells as a possible mechanism of action, supported by the in-silico molecular docking analysis.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Staphylococcus aureus , Humanos , Simulação de Acoplamento Molecular , Cromonas/farmacologia , Escherichia coli , Bases de Schiff/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Sulfanilamida , Ampicilina/farmacologia , Sulfonamidas/farmacologia , Testes de Sensibilidade Microbiana
18.
Rev. Paul. Pediatr. (Ed. Port., Online) ; 42: e2023023, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1514848

RESUMO

ABSTRACT Objective: To analyze the prevalence of off-label and unlicensed prescriptions for a population of neonates admitted to the Neonatal Intensive Care Unit in a hospital in southern Santa Catarina. Methods: Observational study with a cross-sectional design. All neonates admitted to the Intensive Care Unit during the period from March 2020 to March 2021 were included. Data collection was performed through a questionnaire made by the authors and the classification of drugs based on the Electronic Drug Description (Bulário Eletrônico) of the Brazilian Health Regulatory Agency and Drug Dex-Micromedex. Results: Data from 296 neonates were evaluated. The prevalence was 50,7% for prescribing off-label medications and 37,2% for unlicensed medications. The use of drugs was higher in preterm neonates, with low birth weight, 1st minute Apgar between 6-8, 5th minute Apgar between 7-8, and in need of invasive procedures. The most used off-label drugs were ampicillin, gentamicin and fentanyl (92.6, 92.0 and 26.6%, respectively), whereas the most used unlicensed drugs were caffeine, phenobarbital and bromopride (78.1, 16.3 and 10.9%, respectively). Conclusions: This study showed a large percentage of prescriptions made in the off-label (50.7%) and unlicensed (37.2%) form in the Neonatal Intensive Care Unit, corroborating the worrying world scenario. The most exposed neonates were precisely the most vulnerable ones and, among the most commonly prescribed medications, ampicillin and gentamicin stood out in off-label form and caffeine in unlicensed form.


RESUMO Objetivo: Analisar a prevalência de prescrições off-label e não licenciadas uma população de neonatos internados na Unidade de Terapia Intensiva Neonatal em um hospital ao sul de Santa Catarina. Métodos: Estudo observacional com delineamento transversal. Foram incluídos todos os neonatos admitidos na Unidade de Terapia Intensiva durante o período de março de 2020 a março de 2021. A coleta de dados foi realizada a partir de questionário elaborado pelos autores, e a classificação dos medicamentos, com base no Bulário Eletrônico da Agência Nacional de Vigilância Sanitária e no Drug Dex-Micromedex. Resultados: Foram avaliados dados de 296 neonatos. A prevalência foi de 50,7% para prescrição de medicações off-label e 37,2% para medicações não licenciadas. O uso dos fármacos foi maior em neonatos pré-termo, com baixo peso ao nascer, Apgar de 1o minuto entre 6-8, Apgar de 5o minuto entre 7-8, e com necessidade de procedimentos invasivos. Os fármacos off-label mais utilizados foram a ampicilina, gentamicina e fentanil (92,6, 92 e 26,6%, respectivamente), já os fármacos não licenciados mais utilizados foram a cafeína, fenobarbital e bromoprida (78,1, 16,3 e 10,9%, respectivamente). Conclusões: O estudo demonstrou grande porcentagem de prescrições realizadas de forma off-label (50,7%) e não licenciada (37,2%) na Unidade de Terapia Intensiva Neonatal de análise, corroborando o preocupante cenário mundial. Os neonatos mais expostos foram justamente aqueles mais vulneráveis e, entre as medicações mais utilizadas, destacam-se a ampicilina e a gentamicina de modo off-label e a cafeína de modo não licenciado.

19.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469316

RESUMO

Abstract The antioxidant activity of Tetragonisca angustula honey (TAH) and its ethanolic extract (TAEE) were investigated. The total levels of phenolic (TPC) and flavonoids (TFC) were also evaluated. The results for TPC were 19.91 ± 0.38 and 29.37 ± 1.82 mg GAE g-1 and for TFC 0.20 ± 0.02 and 0.14 ± 0.01 mg QE g-1 of TAH and TAEE, respectively. Antioxidant activities were 73.29 ± 0.49% and 93.36 ± 0.27% in the DPPH assay and 71.73 ± 4.07% and 97.86 ± 0.35% in ABTS+ for TAH and TAEE, respectively. The total reducing activity was determined by the method of reducing power (PR) and iron ion (Fe III) and the results varied in PR from 151.7 ± 25.7 and 230.7 ± 25.2 mg GAE L-1, for TAH and TAEE respectively and for (Fe III) in EC50 0.284 in TAEE and 0.687 in TAH. Chemical analysis by HPLC-DAD of the ethanolic extract (TAEE) revealed the presence of ferulic acid as majority phenolic component in the extract. The 1H NMR analysis confirmed this structure and showed the also presence of glucose, citric acid, succinic acid, proline and hydrocarbon derivatives. In addition, the botanical origin was also investigated and showed a multifloral characteristic, having found 19 pollen types with a botanical predominance of the Anacardiaceae family, with Tapirira pollen occurring as predominant (42.6%) and Schinus as secondary (25.7%). The results showed that T. angustula honey is an interesting source of antioxidant phenolic compounds due to its floral origin and can act as a protector of human health when consumed.


Resumo A atividade antioxidante do mel de Tetragonisca angustula (TAH) e seu extrato etanólico (TAEE) foram investigados. Os níveis totais de fenólicos (TPC) e flavonóides (TFC) também foram avaliados. Os resultados para TPC foram 19,91 ± 0,38 e 29,37 ± 1,82 mg GAE g-1 e para TFC 0,20 ± 0,02 e 0,14 ± 0,01 mg QE g-1 de TAH e TAEE, respectivamente. As atividades antioxidantes foram 73,29 ± 0,49% e 93,36 ± 0,27% no ensaio DPPH e 71,73 ± 4,07% e 97,86 ± 0,35% no ABTS+ para TAH e TAEE, respectivamente. A atividade redutora total foi determinada pelo método de poder redutor (PR) e íon ferrico (Fe III) e os resultados variaram em PR de 151,7 ± 25,7 e 230,7 ± 25,2 mg GAE L-1, para TAH e TAEE respectivamente e para (Fe III) em EC50 0,284 em TAEE e 0,687 em TAH. A análise química por HPLC-DAD do extrato etanólico (TAEE) revelou a presença de ácido ferúlico como componente majoritário no extrato. A análise de RMN 1H confirmou esta estrutura e mostrou a presença de glicose, ácido cítrico, ácido succínico, prolina e derivados de hidrocarbonetos no TAEE. Além disso, a origem botânica também foi investigada e apresentou característica multifloral, tendo encontrado 19 tipos polínicos com predomínio botânico da família Anacardiaceae, sendo o pólen Tapirira predominante (42,6%) e o Schinus secundário (25,7%). Os resultados mostraram que o mel de T. angustula é uma interessante fonte de compostos fenólicos antioxidantes devido à sua origem floral e pode atuar como protetor da saúde humana quando consumido.

20.
Arq. bras. cardiol ; Arq. bras. cardiol;121(2): e20230462, 2024. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1556998

RESUMO

Resumo Fundamento O infarto do miocárdio com elevação do segmento ST (IAMCSST) é uma das principais causas de doenças cardiovasculares fatais, que têm sido a principal causa de mortalidade em todo o mundo. O diagnóstico na fase inicial beneficiaria a intervenção clínica e o prognóstico, mas ainda falta a exploração dos biomarcadores do IAMCSST. Objetivos Neste estudo, conduzimos uma análise bioinformática para identificar potenciais biomarcadores cruciais no progresso do IAMCSST. Métodos Obtivemos GSE59867 para pacientes com IAMCSST e doença arterial coronariana estável (DACE). Genes diferencialmente expressos (GDEs) foram selecionados com o limiar de -log2fold change- > 0,5 e p < 0,05. Com base nesses genes, conduzimos análises de enriquecimento para explorar a relevância potencial entre genes e para rastrear genes centrais. Posteriormente, os genes centrais foram analisados para detectar miRNAs relacionados e DAVID para detectar fatores de transcrição para análise posterior. Finalmente, o GSE62646 foi utilizado para avaliar a especificidade dos GDEs, com genes demonstrando resultados de AUC superiores a 75%, indicando seu potencial como candidatos a biomarcadores. Posteriormente, os genes centrais foram analisados para detectar miRNAs relacionados e DAVID para detectar fatores de transcrição para análise posterior. Finalmente, o GSE62646 foi utilizado para avaliar a especificidade dos GDEs, com genes demonstrando resultados de AUC superiores a 75%, indicando seu potencial como candidatos a biomarcadores. Resultados 133 GDEs entre DACE e IAMCSST foram obtidos. Em seguida, a rede PPI de GDEs foi construída usando String e Cytoscape, e análises posteriores determinaram genes centrais e 6 complexos moleculares. A análise de enriquecimento funcional dos GDEs sugere que as vias relacionadas à inflamação, metabolismo e imunidade desempenham um papel fundamental na progressão de DACE para IAMCSST. Além disso, foram previstos miRNAs relacionados, has-miR-124, has-miR-130a/b e has-miR-301a/b regularam a expressão do maior número de genes. Enquanto isso, a análise dos fatores de transcrição indica que EVI1, AML1, GATA1 e PPARG são os genes mais enriquecidos. Finalmente, as curvas ROC demonstram que MS4A3, KLRC4, KLRD1, AQP9 e CD14 exibem alta sensibilidade e especificidade na previsão de IAMCSST. Conclusões Este estudo revelou que imunidade, metabolismo e inflamação estão envolvidos no desenvolvimento de IAMCSST derivado de DACE, e 6 genes, incluindo MS4A3, KLRC4, KLRD1, AQP9, CD14 e CCR1, poderiam ser empregados como candidatos a biomarcadores para IAMCSST.


Abstract Background ST-segment elevation myocardial infarction (STEMI) is one of the leading causes of fatal cardiovascular diseases, which have been the prime cause of mortality worldwide. Diagnosis in the early phase would benefit clinical intervention and prognosis, but the exploration of the biomarkers of STEMI is still lacking. Objectives In this study, we conducted a bioinformatics analysis to identify potential crucial biomarkers in the progress of STEMI. Methods We obtained GSE59867 for STEMI and stable coronary artery disease (SCAD) patients. Differentially expressed genes (DEGs) were screened with the threshold of -log2fold change- > 0.5 and p <0.05. Based on these genes, we conducted enrichment analysis to explore the potential relevance between genes and to screen hub genes. Subsequently, hub genes were analyzed to detect related miRNAs and DAVID to detect transcription factors for further analysis. Finally, GSE62646 was utilized to assess DEGs specificity, with genes demonstrating AUC results exceeding 75%, indicating their potential as candidate biomarkers. Results 133 DEGs between SCAD and STEMI were obtained. Then, the PPI network of DEGs was constructed using String and Cytoscape, and further analysis determined hub genes and 6 molecular complexes. Functional enrichment analysis of the DEGs suggests that pathways related to inflammation, metabolism, and immunity play a pivotal role in the progression from SCAD to STEMI. Besides, related-miRNAs were predicted, has-miR-124, has-miR-130a/b, and has-miR-301a/b regulated the expression of the largest number of genes. Meanwhile, Transcription factors analysis indicate that EVI1, AML1, GATA1, and PPARG are the most enriched gene. Finally, ROC curves demonstrate that MS4A3, KLRC4, KLRD1, AQP9, and CD14 exhibit both high sensitivity and specificity in predicting STEMI. Conclusions This study revealed that immunity, metabolism, and inflammation are involved in the development of STEMI derived from SCAD, and 6 genes, including MS4A3, KLRC4, KLRD1, AQP9, CD14, and CCR1, could be employed as candidate biomarkers to STEMI.

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