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1.
Molecules ; 29(3)2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38338371

RESUMEN

This work presents a framework for evaluating hybrid nanoflowers using Burkholderia cepacia lipase. It was expanded on previous findings by testing lipase hybrid nanoflowers (hNF-lipase) formation over a wide range of pH values (5-9) and buffer concentrations (10-100 mM). The free enzyme activity was compared with that of hNF-lipase. The analysis, performed by molecular docking, described the effect of lipase interaction with copper ions. The morphological characterization of hNF-lipase was performed using scanning electron microscopy. Fourier Transform Infrared Spectroscopy performed the physical-chemical characterization. The results show that all hNF-lipase activity presented values higher than that of the free enzyme. Activity is higher at pH 7.4 and has the highest buffer concentration of 100 mM. Molecular docking analysis has been used to understand the effect of enzyme protonation on hNF-lipase formation and identify the main the main binding sites of the enzyme with copper ions. The hNF-lipase nanostructures show the shape of flowers in their micrographs from pH 6 to 8. The spectra of the nanoflowers present peaks typical of the amide regions I and II, current in lipase, and areas with P-O vibrations, confirming the presence of the phosphate group. Therefore, hNF-lipase is an efficient biocatalyst with increased catalytic activity, good nanostructure formation, and improved stability.


Asunto(s)
Cobre , Nanoestructuras , Estabilidad de Enzimas , Cobre/química , Lipasa/química , Simulación del Acoplamiento Molecular , Nanoestructuras/química , Enzimas Inmovilizadas/química , Espectroscopía Infrarroja por Transformada de Fourier , Iones
2.
Int J Nanomedicine ; 17: 2865-2881, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35795081

RESUMEN

Introduction: Gene therapy is a promising approach to be applied in cardiac regeneration after myocardial infarction and gene correction for inherited cardiomyopathies. However, cardiomyocytes are crucial cell types that are considered hard-to-transfect. The entrapment of nucleic acids in non-viral vectors, such as lipid nanoparticles (LNPs), is an attractive approach for safe and effective delivery. Methods: Here, a mini-library of engineered LNPs was developed for pDNA delivery in cardiomyocytes. LNPs were characterized and screened for pDNA delivery in cardiomyocytes and identified a lead LNP formulation with enhanced transfection efficiency. Results: By varying lipid molar ratios, the LNP formulation was optimized to deliver pDNA in cardiomyocytes with enhanced gene expression in vitro and in vivo, with negligible toxicity. In vitro, our lead LNP was able to reach a gene expression greater than 80%. The in vivo treatment with lead LNPs induced a twofold increase in GFP expression in heart tissue compared to control. In addition, levels of circulating myeloid cells and inflammatory cytokines remained without significant changes in the heart after LNP treatment. It was also demonstrated that cardiac cell function was not affected after LNP treatment. Conclusion: Collectively, our results highlight the potential of LNPs as an efficient delivery vector for pDNA to cardiomyocytes. This study suggests that LNPs hold promise to improve gene therapy for treatment of cardiovascular disease.


Asunto(s)
Lípidos , Miocitos Cardíacos , ADN/genética , Liposomas , Nanopartículas , Plásmidos/genética
3.
J Funct Biomater ; 13(2)2022 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-35466227

RESUMEN

The quest for an ideal biomaterial perfectly matching the microenvironment of the surrounding tissues and cells is an endless challenge within biomedical research, in addition to integrating this with a facile and sustainable technology for its preparation. Engineering hydrogels through click chemistry would promote the sustainable invention of tailor-made hydrogels. Herein, we disclose a versatile and facile catalyst-free click chemistry for the generation of an innovative hydrogel by combining chondroitin sulfate (CS) and polyethylene glycol (PEG). Various multi-armed PEG-Norbornene (A-PEG-N) with different molecular sizes were investigated to generate crosslinked copolymers with tunable rheological and mechanical properties. The crosslinked and mechanically stable porous hydrogels could be generated by simply mixing the two clickable Tetrazine-CS (TCS) and A-PEG-N components, generating a self-standing hydrogel within minutes. The leading candidate (TCS-8A-PEG-N (40 kD)), based on the mechanical and biocompatibility results, was further employed as a scaffold to improve wound closure and blood flow in vivo. The hydrogel demonstrated not only enhanced blood perfusion and an increased number of blood vessels, but also desirable fibrous matrix orientation and normal collagen deposition. Taken together, these results demonstrate the potential of the hydrogel to improve wound repair and hold promise for in situ skin tissue engineering applications.

4.
Biotechnol Appl Biochem ; 68(4): 801-808, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33180374

RESUMEN

Guava seed biochar appears as a new alternative of the effective support to the immobilization of Burkholderia cepacia lipase (BCL) by physical adsorption. The objective of this work was to evaluate the potential of this immobilized biocatalyst in the transesterification reaction of crude coconut oil and ethanol and to understand the mechanism of the reaction through the study of molecular docking. The best loading of BCL was determined to be 0.15 genzyme /gsupport having a hydrolytic activity of 260 U/g and 54% immobilization yield. The products of transesterification reaction produced a maximum yield at 40 °C under different reaction conditions. The monoacylglycerols (MAGs) conversion of 59% was using substrate molar ratio oil:ethanol of 1:7 with the reaction time of 24 H. In addition, the highest ethyl esters yield (48%) had the molar ratio of 1:7 with the reaction time of 96 H and maximum conversion of diacylglycerols (DAGs) was 30% with the molar ratio of 1:6 with the reaction time of 24 H. Molecular Docking was applied to clarify the mechanisms of transesterification reaction at the molecular level. MAGs and DAGs are compounds with excellent emulsifying properties used in industrial production of several bioproducts such as cosmetic, pharmaceuticals, foods, and lubricants.


Asunto(s)
Proteínas Bacterianas/química , Burkholderia cepacia/enzimología , Carbón Orgánico/química , Aceite de Coco/química , Enzimas Inmovilizadas/química , Lipasa/química , Esterificación
5.
Occup Ther Int ; 2020: 8150718, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32110165

RESUMEN

Introduction. The Functional Mobility Assessment (FMA) measures satisfaction with mobility devices in daily life. However, in Brazil, there is a lack of instruments which measure functional mobility. OBJECTIVE: We aim to report the cross-cultural adaptation process and face validity of the FMA for use in Brazil. METHODS: Two international guidelines were used in the cross-cultural adaptation process. Two independent translators translated the instrument from English to Brazilian Portuguese, and the two versions were reconciled. Two different translators back translated this reconciled version, and an expert committee analysed the resulting synthesis. For face validity, the FMA was applied with 24 participants, divided into two groups, users with disabilities (n = 12) and occupational therapy students (n = 12) and occupational therapy students (. RESULTS: The cross-cultural adaptation of the FMA was concluded, and its face validity presented that both groups understood most or completely all instrument items. CONCLUSION: The Brazilian version of FMA is now available in Brazilian Portuguese and has face validation. Further studies should test its psychometric properties.


Asunto(s)
Evaluación de la Discapacidad , Encuestas y Cuestionarios , Adulto , Brasil , Comparación Transcultural , Femenino , Humanos , Masculino , Persona de Mediana Edad , Terapia Ocupacional , Portugal/etnología , Psicometría , Reproducibilidad de los Resultados , Traducciones , Adulto Joven
6.
Biotechnol Appl Biochem ; 66(5): 823-832, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31206795

RESUMEN

Alternative strategies are required to develop the optimized production of fatty acids using biocatalysis; molecular docking and response surface methodology are efficient tools to achieve this goal. In the present study, we demonstrate a novel and robust methodology for the sustainable production of fatty acids from Moringa oleifera Lam oil using lipase-catalyzed hydrolysis (without the presence of emulsifiers or buffer solutions). Seven commercial lipases from Candida rugosa (CRL), Burkholderia cepacia (BCL), Thermomyces lanuginosus (TLL), Rhizopus niveus (RNL), Pseudomonas fluorescens (PFL), Mucor javanicus (MJL), and porcine pancreas (PPL) were used as biocatalysts. Initial screening showed that CRL had the highest hydrolytic activity (hydrolysis degree of 81%). Molecular docking analysis contributed to the experimental results, showing that CRL displays more stable binding free energy with oleic acid (C18:1), which is the fatty acid of highest concentration in Moringa oleifera Lam oil. To evaluate and optimize the hydrolysis process, response surface methodology (RSM) was used. The effect of temperature, mass ratio oil:water, and hydrolytic activity on enzymatic hydrolysis was evaluated by central composite design using RSM. Under the optimized conditions (temperature of 37 °C, mass ratio oil:water of 25%, and hydrolytic activity of 550 U goil -1 ), the maximum hydrolysis degree (100%) was achieved. The present study provides a robust method for the enzymatic hydrolysis of different oils for efficient and sustainable fatty acid production.


Asunto(s)
Ácidos Grasos/análisis , Lipasa/metabolismo , Simulación del Acoplamiento Molecular , Moringa oleifera/metabolismo , Aceites de Plantas/metabolismo , Biocatálisis , Hidrólisis , Moringa oleifera/química , Aceites de Plantas/química
7.
Rev Med Brux ; 39(4): 250-254, 2018.
Artículo en Francés | MEDLINE | ID: mdl-30320985

RESUMEN

In this article, we propose to review the recent literature on Internet addiction (AI) by addressing several themes : we will begin by detailing the various questions that have arisen over time as to the reality of the syndrome and the responses that have been provided by the clinical and neuroimaging studies ; we will then discuss comorbidity problems as well as factors favoring the emergence of the AI and its consequences on health ; we will then detail the different treatments proposed and in a dialectical spirit, we will discuss the advantages that a moderate use of the Internet can have on the cognitive functioning as well as different tracks for future researches.


Dans cet article, nous nous proposons de passer en revue la littérature récente concernant l'addiction à Internet (AI) en abordant plusieurs thématiques : nous commencerons par détailler les différentes questions qui se sont posées au cours du temps quant à la réalité du syndrome et les réponses qui ont été apportées par la clinique et par les études de neuro-imagerie ; nous traiterons ensuite des problèmes de comorbidité ainsi que des facteurs favorisant l'apparition de l'AI et ses conséquences sur la santé ; nous détaillerons ensuite les différents traitements proposés puis, dans un esprit dialectique, traiterons dans nos conclusions des avantages que peut avoir l'usage modéré d'Internet sur le fonctionnement cognitif ainsi que des différentes pistes pour de futures recherches.


Asunto(s)
Conducta Adictiva , Internet , Conducta Adictiva/etiología , Conducta Adictiva/terapia , Humanos
8.
An Acad Bras Cienc ; 87(4): 2047-53, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26536853

RESUMEN

Studies suggest that frugivorous bats search and select fruit mainly by olfaction so that they can be attracted by smell alone. The aim of this study was to evaluate, in captivity, the behavioural response (number of foraging attempts) of Artibeus lituratus and Carollia perspicillata offered essential oils extracted from ripe fruit of Ficus insipida (Moraceae) and Piper hispidum (Piperaceae) as well as intact fruit wrapped in gauze to attract bats with reduced visual stimuli. Based on previous reports, we hypothesized that A.lituratus would exhibit preference for Ficus fruits/oil while C. perspicillata would prefer Piper fruit/oil. Four arrangements of these attractants were tested in triplicate: P. hispidum fruit vs. F. insipida fruit, P.hispidum oil vs. F. insipida oil, P. hispidum oil vs. F. insipida fruit and P. hispidum fruit vs. F. insipida oil. As expected, in all tests, A. lituratus showed the highest number of foraging attempts in F. insipida while C. perspicillata in those of P. hispidum. Based on the number of foraging attempts both species exhibited a positive response to their favorite fruit genera, though the differences were not always statistically significant. The results confirm the importance of smell in fruit choice by these species.


Asunto(s)
Quirópteros/fisiología , Conducta Alimentaria/fisiología , Ficus , Frutas , Piper , Olfato/fisiología , Animales , Quirópteros/clasificación , Aceites Volátiles
9.
Comp Biochem Physiol C Toxicol Pharmacol ; 156(3-4): 148-58, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22885277

RESUMEN

Native Inga laurina (Fabaceae) trypsin inhibitor (ILTI) was tested for anti-insect activity against Diatraea saccharalis and Heliothis virescens larvae. The addition of 0.1% ILTI to the diet of D. saccharalis did not alter larval survival but decreased larval weight by 51%. The H. virescens larvae that were fed a diet containing 0.5% ILTI showed an 84% decrease in weight. ILTI was not digested by the midgut proteinases of either species of larvae. The trypsin levels were reduced by 55.3% in the feces of D. saccharalis and increased by 24.1% in the feces of H. virescens. The trypsin activity in both species fed with ILTI was sensitive to the inhibitor, suggesting that no novel proteinase resistant to ILTI was induced. Additionally, ILTI exhibited inhibitory activity against the proteinases present in the larval midgut of different species of Lepidoptera. The organization of the ilti gene was elucidated by analyzing its corresponding genomic sequence. The recombinant ILTI protein (reILTI) was expressed and purified, and its efficacy was evaluated. Both native ILTI and reILTI exhibited a similar strong inhibitory effect on bovine trypsin activity. These results suggest that ILTI presents insecticidal properties against both insects and may thus be a useful tool in the genetic engineering of plants.


Asunto(s)
Fabaceae/enzimología , Lepidópteros/efectos de los fármacos , Control Biológico de Vectores/métodos , Proteínas de Plantas/farmacología , Inhibidores de Tripsina/farmacología , Animales , Secuencia de Bases , Clonación Molecular , Activación Enzimática , Pruebas de Enzimas/métodos , Escherichia coli/genética , Fabaceae/genética , Heces/química , Genes de Plantas , Insecticidas/farmacología , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Proteínas de Plantas/genética , Proteolisis , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/farmacología , Semillas/enzimología , Inhibidores de Tripsina/genética , Pérdida de Peso
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