Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Artigo em Inglês | MEDLINE | ID: mdl-38158527

RESUMO

The removal of dyes from effluents of textile industries represents a technological challenge, due to their significant environmental impact. The application of halloysite (Hal) and palygorskite (Pal) clay minerals as adsorbents for the removal of Congo red (CR) and methylene blue (MB) was evaluated in this work. The materials were applied both in natural and acid-treated forms, and characterized by XRD, XPS, SEM-EDS, FTIR, and N2 adsorption-desorption isotherm techniques to identify their properties and main active sites. The adsorbents showed potential to remove CR (> 98%) and MB (> 85%) within 180 min, using 0.3 g adsorbent and initial dye concentration of 250 mg L-1. Semi-empirical quantum mechanical calculations (SQM) confirmed the interaction mechanism between dyes and the adsorbents via chemisorption (- 69.0 kcal mol-1 < Eads < - 28.8 kcal mol-1), which was further observed experimentally due to the high fit of adsorption data to pseudo-second order kinetic model (R2 > 0.99) and Langmuir isotherm (R2 > 0.98). The use of Pal and Hal to remove dyes was proven to be economically and environmentally viable for industrial application.

2.
J Cardiovasc Electrophysiol ; 34(1): 24-34, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36317466

RESUMO

INTRODUCTION: Recurrence of atrial fibrillation (AF) within the blanking period after catheter ablation (CA) is traditionally classified as a transient and benign event. However, recent findings suggest that early recurrence (ER) is associated with late recurrence (LR), challenging the predefined "blanking period". We aimed to determine the clinical and procedural predictors of ER and LR after CA and establish the risk of LR in patients who experience ER. METHODS AND RESULTS: Retrospective single-centre study including all patients who underwent a first procedure of AF CA between 2017 and 2019. ER was defined as any recurrence of AF, atrial flutter or atrial tachycardia >30 s within 90 days after CA and LR as any recurrence after 90 days of CA. A total of 399 patients were included, 37% women, median age of 58 years [49-66] and 77% had paroxysmal AF. Median follow-up was 33 months (from 13 to 61). ER after CA was present in 14% of the patients, and LR was reported in 32%. Among patients who experienced ER, 84% also had LR (p < .001). Patients with ER had a higher prevalence of moderate/severe valvular heart disease, persistent AF, previous electrical cardioversion, a larger left atrium, higher coronary artery calcium score, and higher rates of intraprocedural electrical cardioversion and cardiac fibrosis on eletroanatomical mapping compared with patients without ER. After covariate adjustment, ER and female sex were defined as independent predictors of LR (hazard ratio [HR] 4.69; 95% confidence interval [CI], 2.99-7.35; p < .001 and HR 2.73; 95% CI, 1.47-5.10; p = .002, respectively). CONCLUSION: The risk of LR after an index procedure of CA was significantly higher in patients with ER (five-fold increased risk). These results support the imperative need to clarify the clinical role of the blanking period.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Fibrilação Atrial/etiologia , Estudos Retrospectivos , Relevância Clínica , Resultado do Tratamento , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Recidiva
4.
An Acad Bras Cienc ; 93(4): e20200443, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495202

RESUMO

Phytochemical studies of Cespedesia spathulata (Ochnaceae) leaves using 1H, 13C NMR, and GC-MS have led to the isolation of some metabolites identified for the first time in these species such as cathechin, epicatechin, vitexin, orientin, 6''-O-acetyl-vitexin, sitosterol, stigmasterol, phytol, 4,5-dihydrovomifoliol and a mixture of aliphatic methyl esters, together with ochnaflavone, which was previously isolated from this plant. The modulating activity of some fractions and compounds from Cespedesia spathulata towards tyrosinase enzyme was assayed by spectroscopic and theoretical means/experiments. The dichloromethane fraction (133 µg mL-1) and ochnaflavone (333 µM) inhibited tyrosinase activity by 20 % and 2.0 %, respectively, whereas the ethyl acetate fraction (666 µg mL-1) and ±catechins (catechin and epicatechin - 800 µM) activated it by 104 % and 384 %, respectively. Quantum chemical calculations suggested that catechin and epicatechin are better activators than L-DOPA by interacting with Cu (II) ions. Molecular docking results suggested that hydrogen bonding and hydrophobic interactions are the main binding forces between each tyrosinase activator and the amino acid residues inside the active protein binding pocket.


Assuntos
Ochnaceae , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta
5.
Nanomaterials (Basel) ; 10(10)2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33096705

RESUMO

This review aims to showcase the current use of graphene derivatives, graphene-based nanomaterials in particular, in biopolymer-based composites for food packaging applications. A brief introduction regarding the valuable attributes of available and emergent bioplastic materials is made so that their contributions to the packaging field can be understood. Furthermore, their drawbacks are also disclosed to highlight the benefits that graphene derivatives can bring to bio-based formulations, from physicochemical to mechanical, barrier, and functional properties as antioxidant activity or electrical conductivity. The reported improvements in biopolymer-based composites carried out by graphene derivatives in the last three years are discussed, pointing to their potential for innovative food packaging applications such as electrically conductive food packaging.

6.
Chemosphere ; 252: 126563, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32443264

RESUMO

Climate change is leading to a gradual increase in the ocean temperature, which can cause physiological and biochemical impairments in aquatic organisms. Along with the environmental changes, the presence of emerging pollutants such as titanium dioxide (TiO2) in marine coastal systems has also been a topic of concern, especially considering the interactive effects that both factors may present to inhabiting organisms. In the present study, it has been assessed the effects of the presence in water of particles of rutile, the most common polymorph of TiO2, in Mytilus galloprovincialis, under actual and predicted warming conditions. Organisms were exposed to different concentrations of rutile (0, 5, 50, 100 µg/L) at control (18 ± 1.0 °C) and increased (22 ± 1.0 °C) temperatures. Histopathological and biochemical changes were evaluated in mussels after 28 days of exposure. Histopathological examination revealed similar alterations on mussels' gills and digestive glands with increasing rutile concentrations at both temperatures. Biochemical markers showed that contaminated mussels have an unchanged metabolic capacity at 18 °C, which increased at 22 °C. Although antioxidant defences were activated in contaminated organisms at 22 °C, cellular damage was still observed. Overall, our findings showed that histopathological impacts occurred after rutile exposure regardless of the temperature, while biochemical alterations were only significantly noticeable when temperature was enhanced to 22 °C. Thus, this study demonstrated that temperature rise may significantly enhance the sensitivity of bivalves towards emerging pollutants.


Assuntos
Mytilus/fisiologia , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Mudança Climática , Brânquias/metabolismo , Mytilus/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Temperatura , Poluentes Químicos da Água/análise
7.
J Phys Act Health ; 17(2): 156-161, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31810065

RESUMO

BACKGROUND: To compare the acute effects of water-based aerobic-resistance and resistance-aerobic concurrent training (CT) sessions on energy expenditure (EE) during and postexercise in young women. METHODS: Nine active women (24 [3] y; 60 [5] kg) completed 4 sessions: (1) familiarization, (2) aquatic maximal test to determine the heart rate corresponding to the anaerobic threshold, (3) CT protocol with aerobic-resistance sequence, and (4) CT protocol with resistance-aerobic sequence. Both protocols started and ended with the participants in the supine position for 30 minutes to perform resting and postexercise oxygen consumption measurements. The water-based resistance protocol comprised 4 sets of 15 seconds at maximal velocity, and the water-based aerobic protocol was performed at a continuous intensity (heart rate corresponding to the anaerobic threshold). EE measurements were calculated based on oxygen consumption and the corresponding caloric equivalent. Paired t test was used to compare the EE values between the water-based CT intrasession exercise sequences (α = .05). RESULTS: There was no difference between the water-based aerobic-resistance and resistance-aerobic in total EE (330.78 vs 329.56 kcal; P = .96), EE per minute (7.35 vs 7.32 kcal·min-1; P = .96), and postexercise EE (63.65 vs 59.92 kcal; P = .50). CONCLUSIONS: The intrasession exercise sequence during water-based CT had no influence on the EE in young women.


Assuntos
Metabolismo Energético/fisiologia , Exercício Físico/fisiologia , Água/fisiologia , Adolescente , Adulto , Feminino , Humanos , Adulto Jovem
8.
Sci Total Environ ; 719: 134886, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31837882

RESUMO

Titanium dioxide (TiO2) particles have been widely used in various industrial applications and consumer products. Due to their large production and use, they will eventually enter into aquatic environments. Once in the aquatic environment TiO2 particles may interact with the organisms and induce toxic effects. Since the most common crystallographic forms of TiO2 are rutile and anatase, the present study evaluated the effect of these two forms of TiO2 particles in Mytilus galloprovincialis. For this, mussels were exposed to different concentrations of rutile and anatase particles (0, 5, 50, 100 µg/L) for twenty-eight days. Ti concentrations, histopathological alterations and biochemical effects were evaluated. Similar Ti concentrations were found in mussels exposed to rutile and anatase, with the highest values in mussels exposed to the highest exposure concentration. Histopathological results demonstrated that both forms of TiO2 induced alterations on gills and digestive glands along the increasing exposure gradient. Biochemical markers showed that mussels exposed to rutile maintained their metabolic capacity (assessed by the activity of the Electron Transport System, ETS), while anatase increased the metabolism of mussels. Mussels exposed to rutile increased their detoxifying defences which, due to the low tested concentrations, were sufficient to avoid cellular damage. On the other hand, mussels exposed to anatase suffered cellular damages despite the increase of the antioxidant defences which may be related to the high ETS activity. Both rutile and anatase particles were toxic to M. galloprovincialis, being the highest oxidative stress exerted by the crystalline form anatase.


Assuntos
Mytilus , Animais , Estresse Oxidativo , Titânio , Poluentes Químicos da Água
9.
Mol Genet Genomic Med ; 7(12): e998, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31599127

RESUMO

BACKGROUND: Cigarette consumption has been identified as the main non-etiological factor in head and neck cancer (HNC) development. One of the main compounds in cigarettes is nicotine, which binds directly to nicotine acetylcholine receptors (nAchRs) in the body, which are encoded by different genes of the CHRNA family. Polymorphisms in some of these genes have been studied in relation to the risk of HNC and cigarette consumption intensity. The aim of this study was to evaluate whether there were associations between the CHRNA3 (rs578776) and CHRNA5 (rs16969968) polymorphisms and HNC risk and between the polymorphisms and the intensity of cigarette consumption. METHODS: A total of 1,067 individuals from Heliopolis Hospital in São Paulo were investigated, including 619 patients with HNC and 448 patients without diagnosed tumors. All participants answered a questionnaire about sociodemographic information and cigarette consumption data. The polymorphisms were determined by TaqMan genotyping by real-time PCR. RESULTS: The polymorphisms studied, rs578776 (CHRNA3) and rs16969968 (CHRNA5), did not have an association with HNC risk, but the rs16969968 homozygous genotype was associated with increased cigarette consumption intensity (OR 1.93, 95% CI 1.05-3.58). CONCLUSION: The polymorphism CHRNA5 can be considered an indirect risk factor for neoplasms in these Brazilian samples when cigarette consumption increased.


Assuntos
Neoplasias de Cabeça e Pescoço/genética , Proteínas do Tecido Nervoso/genética , Polimorfismo de Nucleotídeo Único , Receptores Nicotínicos/genética , Fumar/epidemiologia , Brasil/epidemiologia , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Neoplasias de Cabeça e Pescoço/induzido quimicamente , Heterozigoto , Humanos , Masculino , Fumar/efeitos adversos , Inquéritos e Questionários
10.
Environ Pollut ; 242(Pt B): 1245-1252, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30118912

RESUMO

Florfenicol is one of the most-used antimicrobial agents in global fish farming. Nevertheless, in most countries, its use is not conducted in accordance with good practices. The aim of this work was to evaluate the leaching of florfenicol from coated fish feed into the water. Analytical methods were developed and validated for the quantitation of florfenicol in medicated feed and water by UHPLC-MS/MS. Florfenicol residues in the water were quantified after 5- and 15-min exposures of the medicated feed in the water at 22 and 28 °C and at pH 4.5 and 8.0. The influence of pellet size and three coating agents (vegetable oil, carboxymethylcellulose, and low-methoxylated pectin) on the leaching of the drug was also assessed. Pellet size, coating agent, water temperature, and time of exposure significantly (p < 0.05) affected florfenicol leaching, while water pH did not interfere with the leaching. Coating with vegetable oil was the most efficient method to reduce florfenicol leaching, while coating with carboxymethylcellulose presented the highest leaching (approximately 60% after 15 min at 28 °C). Thus, the coating agent has a significant effect on the florfenicol leaching rate and, consequently, on the necessary dose of the drug to be administered. Moreover, it is worth mentioning that higher florfenicol leaching will pose a greater risk to environmental health, specifically in terms of the development of bacteria resistant to florfenicol. Additional studies are needed with other polymers and veterinary drugs used in medicated feed for fish farming.


Assuntos
Ração Animal/análise , Tianfenicol/análogos & derivados , Poluentes Químicos da Água/análise , Animais , Antibacterianos/análise , Antibacterianos/metabolismo , Carboximetilcelulose Sódica/química , Cromatografia Líquida de Alta Pressão , Pesqueiros , Peixes , Pectinas/química , Óleos de Plantas/química , Espectrometria de Massas em Tandem , Tianfenicol/análise , Tianfenicol/metabolismo , Água/análise
11.
J Strength Cond Res ; 32(10): 2730-2742, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29746386

RESUMO

Schaun, GZ, Pinto, SS, Silva, MR, Dolinski, DB, and Alberton, CL. Sixteen weeks of whole-body high-intensity interval training induce similar cardiorespiratory responses compared with traditional high-intensity interval training and moderate-intensity continuous training in healthy men. J Strength Cond Res 32(10): 2730-2742, 2018-Low-volume high-intensity interval training (HIIT) protocols that use the body weight as resistance could be an interesting and inexpensive alternative to traditional ergometer-based high-intensity interval training (HIIT-T) and moderate-intensity continuous training (MICT). Therefore, our aim was to compare the effects of 16 weeks of whole-body HIIT (HIIT-WB), HIIT-T, and MICT on maximal oxygen uptake (V[Combining Dot Above]O2max), second ventilatory threshold (VT2), and running economy (RE) outcomes. Fifty-five healthy men (23.7 ± 0.7 years, 1.79 ± 0.01 m, 78.5 ± 1.7 kg) were randomized into 3 training groups (HIIT-T = 17; HIIT-WB = 19; MICT = 19) for 16 weeks (3× per week). The HIIT-T group performed eight 20-second bouts at 130% of the velocity associated to V[Combining Dot Above]O2max (vV[Combining Dot Above]O2max) interspersed by 10-second passive recovery on a treadmill, whereas HIIT-WB group performed the same protocol but used calisthenics exercises at an all-out intensity instead of treadmill running. Finally, MICT group exercised for 30 minutes at 90-95% of the heart rate (HR) associated to VT2. After the intervention, all groups improved V[Combining Dot Above]O2max, vV[Combining Dot Above]O2max, time to exhaustion (Tmax), VT2, velocity associated with VT2 (vVT2), and time to reach VT2 (tVT2) significantly (p < 0.05). Moreover, Tmax, vVT2, and tVT2 were greater after HIIT-T compared with HIIT-WB (p < 0.05), whereas oxygen uptake increased and HR decreased during the RE test in all groups (p < 0.05). Our results demonstrate that HIIT-WB can be as effective as traditional HIIT while also being time-efficient compared with MICT to improve health-related outcomes after 16 weeks of training. However, HIIT-T and MICT seem preferable to enhance performance-related outcomes compared with HIIT-WB.


Assuntos
Adaptação Fisiológica , Treinamento Intervalado de Alta Intensidade/métodos , Consumo de Oxigênio , Corrida/fisiologia , Teste de Esforço , Frequência Cardíaca , Humanos , Masculino , Condicionamento Físico Animal , Adulto Jovem
12.
J. pediatr. (Rio J.) ; 93(1): 87-93, Jan.-Feb. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-841326

RESUMO

Abstract: Objectives: To compare different neonatal outcomes according to the different types of treatments used in the management of gestational diabetes mellitus. Methods: This was a retrospective cohort study. The study population comprised pregnant women with gestational diabetes treated at a public maternity hospital from July 2010 to August 2014. The study included women aged at least 18 years, with a singleton pregnancy, who met the criteria for gestational diabetes mellitus. Blood glucose levels, fetal abdominal circumference, body mass index and gestational age were considered for treatment decision-making. The evaluated neonatal outcomes were: type of delivery, prematurity, weight in relation to gestational age, Apgar at 1 and 5 min, and need for intensive care unit admission. Results: The sample consisted of 705 pregnant women. The neonatal outcomes were analyzed based on the treatment received. Women treated with metformin were less likely to have children who were small for gestational age (95% CI: 0.09-0.66) and more likely to have a newborn adequate for gestational age (95% CI: 1.12-3.94). Those women treated with insulin had a lower chance of having a preterm child (95% CI: 0.02-0.78). The combined treatment with insulin and metformin resulted in higher chance for a neonate to be born large for gestational age (95% CI: 1.14-11.15) and lower chance to be born preterm (95% CI: 0.01-0.71). The type of treatment did not affect the mode of delivery, Apgar score, and intensive care unit admission. Conclusions: The pediatrician in the delivery room can expect different outcomes for diabetic mothers based on the treatment received.


Resumo: Objetivos: Comparar diferentes desfechos neonatais de acordo com as diferentes modalidades de tratamento do diabetes mellitus gestacional. Métodos: Trata-se de uma coorte retrospectiva. A população do estudo foi composta por gestantes com diabetes gestacional atendidas em uma maternidade pública de julho de 2010 a agosto de 2014. Foram incluídas mulheres com idade mínima de 18 anos, gestação única e com critérios para diabetes mellitus gestacional. Para decisão terapêutica foram considerados glicemias, circunferência abdominal fetal, índice de massa corporal e idade gestacional. Os desfechos neonatais avaliados foram: via de parto, prematuridade, relação do peso com idade gestacional, Apgar no 1º e 5º minuto e necessidade de internação em unidade de terapia intensiva. Resultados: A amostra foi composta por 705 gestantes. Os desfechos neonatais foram analisados com base na terapêutica recebida. Mulheres tratadas com metformina tiveram menor chance de ter filhos pequenos para a idade gestacional (IC 95%: 0,09-0,66) e maior chance de ter um filho adequado para a idade gestacional (IC 95%: 1,12-3,94). A gestante tratada com insulina teve menor chance de ter um filho prematuro (IC 95%: 0,02-0,78). O tratamento feito com a associação de insulina e metformina resultou em maior chance de um recém-nascido grande para a idade gestacional (IC 95%: 1,14-11,15) e menor chance de prematuridade (IC 95%: 0,01-0,71). A modalidade de tratamento não interferiu na via de parto, Apgar e internação em terapia intensiva. Conclusões: O pediatra na sala de parto pode esperar diferentes desfechos para o filho de mãe diabética, com base no tratamento recebido.


Assuntos
Humanos , Masculino , Feminino , Gravidez , Recém-Nascido , Adulto , Resultado da Gravidez , Diabetes Gestacional/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Metformina/administração & dosagem , Estudos Retrospectivos , Estudos de Coortes , Quimioterapia Combinada
13.
J Pediatr (Rio J) ; 93(1): 87-93, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27371343

RESUMO

OBJECTIVES: To compare different neonatal outcomes according to the different types of treatments used in the management of gestational diabetes mellitus. METHODS: This was a retrospective cohort study. The study population comprised pregnant women with gestational diabetes treated at a public maternity hospital from July 2010 to August 2014. The study included women aged at least 18 years, with a singleton pregnancy, who met the criteria for gestational diabetes mellitus. Blood glucose levels, fetal abdominal circumference, body mass index and gestational age were considered for treatment decision-making. The evaluated neonatal outcomes were: type of delivery, prematurity, weight in relation to gestational age, Apgar at 1 and 5min, and need for intensive care unit admission. RESULTS: The sample consisted of 705 pregnant women. The neonatal outcomes were analyzed based on the treatment received. Women treated with metformin were less likely to have children who were small for gestational age (95% CI: 0.09-0.66) and more likely to have a newborn adequate for gestational age (95% CI: 1.12-3.94). Those women treated with insulin had a lower chance of having a preterm child (95% CI: 0.02-0.78). The combined treatment with insulin and metformin resulted in higher chance for a neonate to be born large for gestational age (95% CI: 1.14-11.15) and lower chance to be born preterm (95% CI: 0.01-0.71). The type of treatment did not affect the mode of delivery, Apgar score, and intensive care unit admission. CONCLUSIONS: The pediatrician in the delivery room can expect different outcomes for diabetic mothers based on the treatment received.


Assuntos
Diabetes Gestacional/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Metformina/administração & dosagem , Resultado da Gravidez , Adulto , Estudos de Coortes , Quimioterapia Combinada , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Estudos Retrospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...