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1.
Langmuir ; 39(23): 8100-8108, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37235552

RESUMO

Phenylboronic acids (BAs) are important synthetic receptors that bind reversibly to cis-diols enabling their use in molecular sensing. When conjugated to magnetic iron oxide nanoparticles, BAs have potential for application in separations and enrichment. Realizing this will require a new understanding of their inherent binding modes and measurement of their binding capacity and their stability in/extractability from complex environments. In this work, 3-aminophenylboronic acid was functionalized to superparamagnetic iron oxide nanoparticles (MNPs, core diameter 8.9 nm) to provide stable aqueous suspensions of functionalized particles (BA-MNPs). The progress of sugar binding and its impact on BA-MNP colloidal stability were monitored through the pH-dependence of hydrodynamic size and zeta potential during incubation with a range of saccharides. This provided the first direct observation of boronate ionization pKa in grafted BA, which in the absence of sugar shifted to a slightly more basic pH than free BA. On exposure to sugar solutions under MNP-limiting conditions, pKa moved progressively to lower pH as maximum capacity was gradually attained. The pKa shift is shown to be greater for sugars with greater BA binding affinity, and on-particle sugar exchange effects were inferred. Colloidal dispersion of BA-MNPs after binding was shown for all sugars at all pHs studied, which enabled facile magnetic extraction of glucose from agarose and cultured extracellular matrix expanded in serum-free media. Bound glucose, quantified following magnetophoretic capture, was found to be proportional to the solution glucose content under glucose-limiting conditions expected for the application. The implications for the development of MNP-immobilized ligands for selective magnetic biomarker capture and quantitation from the extracellular environment are discussed.


Assuntos
Nanopartículas de Magnetita , Açúcares , Carboidratos , Glucose
2.
Anal Bioanal Chem ; 415(18): 4435-4444, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36872410

RESUMO

A new natural deep eutectic solvent (NADES)-based analytical method for mercury speciation in water samples is presented. A NADES (i.e., decanoic acid:DL-menthol in a molar ratio of 1:2) is used as an environmentally friendly extractant for separation and preconcentration using dispersive liquid-liquid microextraction before LC-UV-Vis. Under optimal extraction conditions (i.e., NADES volume, 50 µL; sample pH, 12; volume of the complexing agent, 100 µL; extraction time, 3 min; centrifugation speed, 3000 rpm; and centrifugation time, 3 min), the limit of detection values were 0.9 µg L-1 for the organomercurial species and 3 µg L-1 for Hg2+, which had a slightly higher value. The relative standard deviation (RSD, n = 6) has been evaluated at two concentration levels (25 and 50 µg L-1) obtaining values for all the mercury complexes within the range of 6-12% and 8-12%, respectively. The trueness of the methodology has been evaluated using five real water samples from four different sources (i.e., tap, river, lake, and wastewater). The recovery tests have been performed in triplicate obtaining relative recoveries between 75 and 118%, with RSD (n = 3) between 1 and 19%, for all the mercury complexes in surface water samples. However, wastewater sample showed a significant matrix effect (recoveries ranged between 45 and 110%), probably due to the high amount of organic matter. Finally, the greenness of the method has also been evaluated by the analytical greenness metric for sample preparation (i.e., AGREEprep).


Assuntos
Microextração em Fase Líquida , Mercúrio , Poluentes Químicos da Água , Mercúrio/análise , Solventes/química , Solventes Eutéticos Profundos , Águas Residuárias , Poluentes Químicos da Água/análise , Microextração em Fase Líquida/métodos , Água/química , Limite de Detecção
3.
Int J Mol Sci ; 23(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36499084

RESUMO

The purinergic receptor P2X7 (P2X7R) is implicated in all neurodegenerative diseases of the central nervous system. It is also involved in the retinal degeneration associated with glaucoma, age-related macular degeneration, and diabetic retinopathy, and its overexpression in the retina is evident in these disorders. Retinitis pigmentosa is a progressive degenerative disease that ultimately leads to blindness. Here, we investigated the expression of P2X7R during disease progression in the rd10 mouse model of RP. As the purinergic receptor P2X4 is widely co-expressed with P2X7R, we also studied its expression in the retina of rd10 mice. The expression of P2X7R and P2X4R was examined by immunohistochemistry, flow cytometry, and western blotting. In addition, we analyzed retinal functionality by electroretinographic recordings of visual responses and optomotor tests and retinal morphology. We found that the expression of P2X7R and P2X4R increased in rd10 mice concomitant with disease progression, but with different cellular localization. Our findings suggest that P2X7R and P2X4R might play an important role in RP progression, which should be further analyzed for the pharmacological treatment of inherited retinal dystrophies.


Assuntos
Receptores Purinérgicos P2X4 , Receptores Purinérgicos P2X7 , Retinose Pigmentar , Animais , Camundongos , Modelos Animais de Doenças , Progressão da Doença , Eletrorretinografia , Camundongos Endogâmicos C57BL , Receptores Purinérgicos P2X7/genética , Retinose Pigmentar/genética , Receptores Purinérgicos P2X4/genética
4.
J Sep Sci ; 43(9-10): 1808-1816, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31821691

RESUMO

A novel approach is presented to determine four bisphenols in water and urine samples, employing magnetic dispersive solid-phase extraction combined with liquid chromatography and diode array detection. A modified zeolite-based magnetic composite was used as an efficient sorbent, combining the advantages of magnetic materials with the remarkable properties of zeolites. A multivariate optimization design was employed to optimize some experimental factors affecting magnetic dispersive solid-phase extraction. The method was evaluated under optimized conditions (i.e., amount of sorbent, 50 mg; sample pH, unadjusted; NaCl concentration, 1.25%; extraction and elution time, 2 min; eluent solvent, ethanol; eluent solvent volume, 400 µL), obtaining good linearity with correlation coefficients ranging between 0.995 and 0.999 (N = 5) (from 2 to 250 µg/L for bisphenol A, bisphenol AP, and bisphenol P and from 5 to 250 µg/L for bisphenol AF). Method repeatability was assessed obtaining coefficients of variation between 3 and 11% (n = 6). Finally, the method was applied to spiked real samples, obtaining for water samples relative recoveries between 83 and 105%, and for urine samples between 81 and 108% for bisphenol A, bisphenol AP, and bisphenol AF, and between 47 and 59% for bisphenol P.


Assuntos
Compostos Férricos/química , Fenóis/análise , Extração em Fase Sólida , Poluentes Químicos da Água/química , Zeolitas/química , Cromatografia Líquida , Voluntários Saudáveis , Humanos , Fenômenos Magnéticos
5.
Mikrochim Acta ; 187(1): 87, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31897613

RESUMO

Magnetic dispersive solid-phase extraction (MDSPE) is combined with electrochemical detection by using a screen-printed carbon electrode modified with gold nanoparticles to determine lead(II). A zeolite-based magnetic composite was used as sorbent during sample preparation, thus combining the unique properties of zeolites as sorbent materials with the remarkable advantages provided by magnetic materials. Three different zeolite-based magnetic composites were initially investigated and characterized. ZSM-5/Fe2O3 treated with HNO3 (ZSM-5/Fe2O3(tr)) was finally selected as sorbent. Lead was extracted from urine samples using ZSM-5/Fe2O3(tr). After extraction, the phases were separated by using an external magnet. Subsequently, the magnetic composite carrying the analyte was directly deposited onto the working electrode of a modified screen-printed carbon electrode for final electrochemical detection. Thereby, the elution and detection of Pb(II) were carried out in a single step. A multivariate approach was employed to optimize the experimental parameters affecting extraction. Under optimized conditions and at a typical working potential of -0.23 V (vs. Ag pseudo-reference electrode), response is linear in the 0 to 25 µg L-1 Pb(II) concentration range. The empirical limit of detection ranged from 1.0 to 2.0 µg L-1. The method was used to analyze Pb(II)-spiked urine samples, and apparent recoveries ranged between 99 and 107%, with coefficients of variation of <20%. Graphical abstractSchematic presentation of the analytical method to determine lead(II) in urine samples. Magnetic dispersive solid-phase extraction using a zeolite-based composite (ZSM-5/Fe2O3(tr)) is directly combined with electrochemical detection by using a screen-printed carbon electrode modified with gold nanoparticles (SPCnAuE).

6.
Analyst ; 144(2): 366-387, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30468438

RESUMO

Zeolites are ordered crystalline materials with a promising performance for a wide range of applications such as catalysis, petrochemistry, environmental remediation, and medicine, but have scarcely been evaluated in Analytical Chemistry. Their unique and fascinating properties such as their high surface area, high adsorption capacity and molecular selectivity, chemical and thermal stability, ion-exchange capacity, low cost extraction and synthesis, and their easy modification, which provides a wide range of zeolite-based materials, make zeolites potential sorbents for extraction procedures. Therefore, in this review, we provide an overview of the current status of zeolites and zeolite-based materials used in extraction and microextraction techniques with reference to recent applications and highlight some of the novel advances.

7.
J Chem Inf Model ; 58(7): 1384-1396, 2018 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-29898360

RESUMO

Machine learning (ML) algorithms are gaining importance in the processing of chemical information and modeling of chemical reactivity problems. In this work, we have developed a perturbation-theory and machine learning (PTML) model combining perturbation theory (PT) and ML algorithms for predicting the yield of a given reaction. For this purpose, we have selected Parham cyclization, which is a general and powerful tool for the synthesis of heterocyclic and carbocyclic compounds. This reaction has both structural (substitution pattern on the substrate, internal electrophile, ring size, etc.) and operational variables (organolithium reagent, solvent, temperature, time, etc.), so predicting the effect of changes on substrate design (internal elelctrophile, halide, etc.) or reaction conditions on the yield is an important task that could help to optimize the reaction design. The PTML model developed uses PT operators to account for perturbations under experimental conditions and/or structural variables of all the molecules involved in a query reaction, compared to a reaction of reference. Thus, a dataset of >100 reactions has been collected for different substrates and internal electrophiles, under different reaction conditions, with a wide range of yields (0-98%). The best PTML model found using General Linear Regression (GLR) has R = 0.88 in training and R = 0.83 in external validation series for 10 000 pairs of query and reference reactions. The PTML model has a final R = 0.95 for all reactions using multiple reactions of reference. We also report a comparative study of linear versus nonlinear PTML models based on artificial neural network (ANN) algorithms. PTML-ANN models (LNN, MLP, RBF) with R ≈ 0.1-0.8 do not outperform the first PMTL model. This result confirms the validity of the linearity of the model. Next, we carried out an experimental and theoretical study of nonreported Parham reactions to illustrate the practical use of the PTML model. A 500 000-point simulation and a Hammett analysis of the reactivity space of Parham reactions are also reported.


Assuntos
Ensaios de Triagem em Larga Escala/métodos , Lítio/química , Aprendizado de Máquina , Modelos Químicos , Compostos Organometálicos/química , Algoritmos , Ciclização , Bases de Dados de Compostos Químicos , Isoquinolinas/síntese química , Isoquinolinas/química , Modelos Lineares , Estrutura Molecular , Redes Neurais de Computação , Relação Estrutura-Atividade , Termodinâmica
8.
Anal Bioanal Chem ; 410(19): 4679-4687, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29170797

RESUMO

A new, fast, easy to handle, and environmentally friendly magnetic headspace single-drop microextraction (Mag-HS-SDME) based on a magnetic ionic liquid (MIL) as an extractant solvent is presented. A small drop of the MIL 1-ethyl-3-methylimidazolium tetraisothiocyanatocobaltate(II) ([Emim]2[Co(NCS)4]) is located on one end of a small neodymium magnet to extract nine chlorobenzenes (1,2-dichlorobenzene, 1,3-dichlorobenzene, 1,4-dichlorobenzene, 1,2,3-trichlorobenzene, 1,2,4-trichlorobenzene, 1,3,5-trichlorobenzene, 1,2,3,4-tetrachlorobenzene, 1,2,4,5-tetrachlorobenzene, and pentachlorobenzene) as model analytes from water samples prior to thermal desorption-gas chromatography-mass spectrometry determination. A multivariate optimization strategy was employed to optimize experimental parameters affecting Mag-HS-SDME. The method was evaluated under optimized extraction conditions (i.e., sample volume, 20 mL; MIL volume, 1 µL; extraction time, 10 min; stirring speed, 1500 rpm; and ionic strength, 15% NaCl (w/v)), obtaining a linear response from 0.05 to 5 µg L-1 for all analytes. The repeatability of the proposed method was evaluated at 0.7 and 3 µg L-1 spiking levels and coefficients of variation ranged between 3 and 18% (n = 3). Limits of detection were in the order of nanograms per liter ranging from 4 ng L-1 for 1,4-dichlorobenzene and 1,2,3,4-tetrachlorobenzene to 8 ng L-1 for 1,2,4,5-tetrachlorobenzene. Finally, tap water, pond water, and wastewater were selected as real water samples to assess the applicability of the method. Relative recoveries varied between 82 and 114% showing negligible matrix effects. Graphical abstract Magnetic headspace single-drop microextraction followed by thermal desorption-gas chromatography-mass spectrometry.


Assuntos
Clorobenzenos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Líquidos Iônicos/química , Microextração em Fase Líquida/métodos , Magnetismo/métodos , Poluentes Químicos da Água/isolamento & purificação , Clorobenzenos/análise , Desenho de Equipamento , Água Doce/análise , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Microextração em Fase Líquida/instrumentação , Magnetismo/instrumentação , Águas Residuárias/análise , Água/análise , Poluentes Químicos da Água/análise
9.
J Sep Sci ; 41(22): 4177-4184, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30239125

RESUMO

A new, fast, simple, and environmentally friendly analytical method has been developed to determine six siloxanes in water samples: octamethyltrisiloxane, octamethylcyclotetrasiloxane, decamethyltetrasiloxane, decamethylcyclopentasiloxane, dodecamethylpentasiloxane and dodecamethylcyclohexasiloxane. The analytical method consists of magnetic solid-phase extraction employing graphene oxide/Fe3 O4 as sorbent for the separation and preconcentration of siloxanes prior to GC-MS determination. The extraction procedure was optimized by means of a Plackett-Burman design. Under the optimized extraction conditions (graphene oxide/Fe3 O4 , 20 mg; extraction time, 10 min; eluent volume, 0.5 mL ACN; elution time, 2.5 min; sample volume, 20 mL), the method rendered repeatability levels with a relative standard deviation between 9 and 20% (n = 6, 10 µg/L). Methodological limits of detection ranged from 0.003 to 0.1 µg/L. The linearity of the method was studied between the methodological limit of quantification and 100 µg/L, obtaining correlation coefficient values between 0.990 and 0.999. The applicability of the method was assessed by analyzing drinking, river and wastewater samples. Relative recovery values ranged between 70 and 120% (1 and 60 µg/L spiking level) showing that the matrix had a negligible effect on extraction. Finally, the greenness of this method was confirmed by the semiquantitative Eco-Scale metrics.

10.
Anal Bioanal Chem ; 409(10): 2665-2674, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28188348

RESUMO

A fast, simple, economical, and environmentally friendly magnetic solid-phase extraction (MSPE) procedure has been developed to preconcentrate 2,4,6-trinitrotoluene (TNT) from water samples prior to determination by liquid chromatography-UV-Vis employing graphene oxide/Fe3O4 nanocomposite as sorbent. The nanocomposite synthesis was investigated, and the MSPE was optimized by a multivariate approach. The optimum MSPE conditions were 40 mg of nanocomposite, 10 min of vortex extraction, 1 mL of acetonitrile as eluent, and 6 min of desorption in an ultrasonic bath. Under the optimized experimental conditions, the method was evaluated to obtain a preconcentration factor of 153. The linearity of the method was studied from 1 to 100 µg L-1 (N = 5), obtaining a correlation coefficient of 0.994. The relative standard deviation and limit of detection were found to be 12% (n = 6, 10 µg L-1) and 0.3 µg L-1, respectively. The applicability of the method was investigated, analyzing three types of water samples (i.e., reservoir and drinking water and effluent wastewater) and recovery values ranged between 87 and 120% (50 µg L-1 spiking level), showing that the matrix had a negligible effect upon extraction. Finally, the semiquantitative Eco-Scale metrics confirmed the greenness of the developed method.


Assuntos
Cromatografia Líquida/métodos , Compostos Férricos/química , Grafite/química , Nanopartículas de Magnetita/química , Nanocompostos/química , Extração em Fase Sólida/métodos , Trinitrotolueno/isolamento & purificação , Água Potável/análise , Água Potável/química , Limite de Detecção , Trinitrotolueno/análise , Águas Residuárias/análise , Águas Residuárias/química
11.
Anal Bioanal Chem ; 409(17): 4215-4223, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28451718

RESUMO

Complexation-mediated electromembrane extraction (EME) of highly polar basic drugs (log P < -1) was investigated for the first time with the catecholamines epinephrine, norepinephrine, and dopamine as model analytes. The model analytes were extracted as cationic species from urine samples (pH 4), through a supported liquid membrane (SLM) comprising 25 mM 4-(trifluoromethyl)phenylboronic acid (TFPBA) in bis(2-ethylhexyl) phosphite (DEHPi), and into 20 mM formic acid as acceptor solution. EME was performed for 15 min, and 50 V was used as extraction voltage across the SLM. TFPBA served as complexation reagent, and selectively formed boronate esters by reversible covalent binding with the model analytes at the sample/SLM interface. This enhanced the mass transfer of the highly polar model analytes across the SLM, and EME of basic drugs with log P in the range -1 to -2 was shown for the first time. Meanwhile, most matrix components in urine were unable to pass the SLM. Thus, the proposed concept provided highly efficient sample clean-up and the system current across the SLM was kept below 50 µA. Finally, the complexation-mediated EME concept was combined with ultra-high performance liquid chromatography coupled to tandem mass spectrometry and evaluated for quantification of epinephrine and dopamine. Standard addition calibration was applied to a pooled human urine sample. Calibration curves using standards between 25 and 125 µg L-1 gave a high level of linearity with a correlation coefficient of 0.990 for epinephrine and 0.996 for dopamine (N = 5). The limit of detection, calculated as three times signal-to-noise ratio, was 5.0 µg L-1 for epinephrine and 1.8 µg L-1 for dopamine. The repeatability of the method, expressed as coefficient of variation, was 13% (n = 5). The proposed method was finally applied for the analysis of spiked pooled human urine sample, obtaining relative recoveries of 91 and 117% for epinephrine and dopamine, respectively.


Assuntos
Catecolaminas/urina , Técnicas Eletroquímicas/instrumentação , Microextração em Fase Líquida/instrumentação , Membranas Artificiais , Compostos de Boro/química , Catecolaminas/isolamento & purificação , Humanos , Limite de Detecção , Urinálise/instrumentação
12.
Anal Bioanal Chem ; 406(8): 2197-204, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24247549

RESUMO

A novel method is reported, whereby screen-printed electrodes (SPELs) are combined with dispersive liquid-liquid microextraction. In-situ ionic liquid (IL) formation was used as an extractant phase in the microextraction technique and proved to be a simple, fast and inexpensive analytical method. This approach uses miniaturized systems both in sample preparation and in the detection stage, helping to develop environmentally friendly analytical methods and portable devices to enable rapid and onsite measurement. The microextraction method is based on a simple metathesis reaction, in which a water-immiscible IL (1-hexyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide, [Hmim][NTf2]) is formed from a water-miscible IL (1-hexyl-3-methylimidazolium chloride, [Hmim][Cl]) and an ion-exchange reagent (lithium bis[(trifluoromethyl)sulfonyl]imide, LiNTf2) in sample solutions. The explosive 2,4,6-trinitrotoluene (TNT) was used as a model analyte to develop the method. The electrochemical behavior of TNT in [Hmim][NTf2] has been studied in SPELs. The extraction method was first optimized by use of a two-step multivariate optimization strategy, using Plackett-Burman and central composite designs. The method was then evaluated under optimum conditions and a good level of linearity was obtained, with a correlation coefficient of 0.9990. Limits of detection and quantification were 7 µg L(-1) and 9 µg L(-1), respectively. The repeatability of the proposed method was evaluated at two different spiking levels (20 and 50 µg L(-1)), and coefficients of variation of 7 % and 5 % (n = 5) were obtained. Tap water and industrial wastewater were selected as real-world water samples to assess the applicability of the method.


Assuntos
Substâncias Explosivas/isolamento & purificação , Microextração em Fase Líquida/métodos , Trinitrotolueno/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Água Potável/química , Técnicas Eletroquímicas , Substâncias Explosivas/análise , Líquidos Iônicos/química , Microextração em Fase Líquida/instrumentação , Trinitrotolueno/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise
13.
Talanta ; 274: 125939, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38547838

RESUMO

A new simple, fast and environmentally friendly deep eutectic solvent based dispersive liquid-liquid microextraction (DES-based DLLME) methodology assisted by vortex is presented for the separation and preconcentration of three elements (i.e., Fe, Cu and Pb) from edible oil samples (i.e., soybean, sunflower, rapeseed, sesame, and olive oil) prior to the determination by microwave-induced plasma optical emission spectrometry (MIP-OES). The deep eutectic solvent selected as extractant (i.e., choline chloride and ethylene glycol, 1:2) is synthesized and characterized by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (1H NMR) and differential scanning calorimetry (DSC), and the extraction conditions are optimized by a two steps experimental design. Under the optimum extraction conditions (i.e., diluted sample weight: 8.6 g; DES volume: 100 µL; extraction time: 1 min; centrifugation time and speed: 3 min and 3000 rpm; and dispersion system: vortex) the analytical method presents excellent linearity (i.e., R2 values higher than 0.99) in the range 10-500 µg kg-1, repeatability (i.e., CV values lower than 9.2%), and limits of detection (LOD) values of 3, 2 and 0.7 µg kg-1 for Pb, Fe and Cu, respectively. None of the analytes displayed amounts over the upper limit permitted by law, and recovery values of all analytes evaluated in the different samples using external standard calibration were close to 100%, which excludes significant matrix effects. Finally, AGREEprep metric has been used to evaluate the method greenness (final score of 0.47) and it has been compared successfully with previous publications for the same type of analytes and matrices.

14.
J Ren Care ; 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378190

RESUMO

BACKGROUND: Peritonitis is a common and serious complication of peritoneal dialysis and is one of the main causes of peritoneal dialysis technique failure and long-term hemodialysis conversion. OBJECTIVES: The aim of the review was to identify and clarify peritonitis risk factors and learn about strategies employed at international level to prevent and reduce the occurrence of peritoneal dialysis associated infections and their complications. DESIGN: A scoping review. PARTICIPANTS: Adults in pertitoneal dialysis. MEASUREMENTS: The methodology framework of Arksey and O'Malley and PRISMA for Scoping Reviews guidelines were applied. A search was conducted of PubMed, Scopus and CINAHL using terms to identify peritoneal dialysis -associated risk factors and interventions carried out for the prevention and reduction of peritonitis in adult persons living at home. RESULTS: The 17 studies selected were based on work carried out in nine different countries. Eleven articles analysed modifiable risk factors (low educational level, being a foreigner and low adherence to aseptic technique) and non-modifiable risk factors (age and comorbidities) that predispose to peritonitis in peritoneal dialysis. The other six studies applied an intervention to improve the prevalence of peritonitis considering educational practices adapted to patient characteristics and the application of retraining. CONCLUSIONS: Personalised patient training and the identification of risk factors for peritonitis are key to reducing complications and enhancing the survival of peritoneal dialysis patients and the effectiveness of the technique.

15.
Nurse Educ Today ; 134: 106104, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38281351

RESUMO

INTRODUCTION: In a nursing degree critical reasoning competency includes reasoning both inside and outside the clinical setting. One of the major challenges for nursing students is learning concepts at a high abstract level. In this sense, the LEGO® Serious Play method has the potential to improve thinking skills. AIMS: To describe a) which elements of thinking link to the learning of the nursing metaparadigm through the use of the LEGO® Serious Play "four Cs" method b) analyse how this method helps to generate critical reflective thinking in nursing students during the process of application of theoretical knowledge about the nursing metaparadigm in a new situation. METHODS: An interpretive phenomenological analysis, integrating qualitative research methods was implemented as a means of undertaking research facilitated using LEGO® Serious Play method as an innovative method of data collection. RESULTS: 280 participants were recruited. From the analysis of the contributions made to the students' forum, six categories emerged: Starting point, Consciousness, Process, Teamwork, Capacities and Limitations. CONCLUSION: LEGO® Serious Play is an effective method for teaching nursing metaparadigms and helps students acquire and generate new knowledge.


Assuntos
Bacharelado em Enfermagem , Estudantes de Enfermagem , Humanos , Resolução de Problemas , Pensamento , Bacharelado em Enfermagem/métodos , Aprendizagem
16.
Int J Nanomedicine ; 19: 7033-7048, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39015675

RESUMO

Purpose: The anticancer potential of indomethacin and other nonsteroidal anti-inflammatory drugs (NSAIDs) in vitro, in vivo, and in clinical trials is well known and widely reported in the literature, along with their side effects, which are mainly observed in the gastrointestinal tract. Here, we present a strategy for the application of the old drug indomethacin as an anticancer agent by encapsulating it in nanostructured lipid carriers (NLC). We describe the production method of IND-NLC, their physicochemical parameters, and the results of their antiproliferative activity against selected cancer cell lines, which were found to be higher compared to the activity of free indomethacin. Methods: IND-NLC were fabricated using the hot high-pressure homogenization method. The nanocarriers were physicochemically characterized, and their biopharmaceutical behaviour and therapeutic efficacy were evaluated in vitro. Results: Lipid nanoparticles IND-NLC exhibited a particle size of 168.1 nm, a negative surface charge (-30.1 mV), low polydispersity index (PDI of 0.139), and high encapsulation efficiency (over 99%). IND-NLC were stable for over 60 days and retained integrity during storage at 4 °C and 25 °C. The potential therapeutic benefits of IND-NLC were screened using in vitro cancer models, where nanocarriers with encapsulated drug effectively inhibited the growth of breast cancer cell line MDA-MB-468 at dosage 15.7 µM. Conclusion: We successfully developed IND-NLC for delivery of indomethacin to cancer cells and confirmed their antitumoral efficacy in in vitro studies. The results suggest that indomethacin encapsulated in lipid nanoparticles possesses high anticancer potential. Moreover, the presented strategy is highly promising and may offer a new alternative for future therapeutic drug innovations.


Assuntos
Antineoplásicos , Portadores de Fármacos , Indometacina , Lipídeos , Tamanho da Partícula , Indometacina/química , Indometacina/farmacologia , Indometacina/administração & dosagem , Indometacina/farmacocinética , Humanos , Portadores de Fármacos/química , Lipídeos/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Nanopartículas/química , Proliferação de Células/efeitos dos fármacos , Nanoestruturas/química , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/administração & dosagem , Sobrevivência Celular/efeitos dos fármacos
17.
Nanomedicine (Lond) ; : 1-16, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39092498

RESUMO

Aim: Cancer constitutes the second leading cause of death worldwide, with conventional therapies limited by significant side effects. Melatonin (MEL), a natural compound with antitumoral properties, suffers from instability and low solubility. To overcome these issues, MEL was encapsulated into nanostructured lipid carriers (MEL-NLC) containing rosehip oil to enhance stability and boost its antitumoral activity. Methods: MEL-NLC were optimized by a design of experiments approach and characterized for their physicochemical properties. Stability and biopharmaceutical behavior were assessed, along with interaction studies and in vitro antitumoral efficacy against various cancer cell lines. Results: Optimized MEL-NLC exhibited desirable physicochemical characteristics, including small particle size and sustained MEL release, along with long-term stability. In vitro studies demonstrated that MEL-NLC selectively induced cytotoxicity in several cancer cell lines while sparing healthy cells. Conclusion: MEL-NLC represent a promising alternative for cancer, combining enhanced stability and targeted antitumoral activity, potentially overcoming the limitations of conventional treatments.


Despite current advances, cancer is the second cause of death worldwide, but conventional therapies have side effects and limited efficacy. Natural therapies are emerging as suitable alternatives and, among them, Melatonin is a well-known compound with antitumoral properties. However, it is degraded by light, decreasing its therapeutical activity. In order to effectively deliver Melatonin into cancer cells, it has been encapsulated into biodegradable nanoparticles containing rosehip oil, which may boost the antitumoral properties. These nanoparticles have been optimized, showing a small size and a high Melatonin encapsulation, sustained drug release and good stability. Furthermore, in vitro studies demonstrated antitumoral activity against several cancer cell lines, also showing a high internalization inside them. Moreover, studies conducted using chicken embryonated eggs, showed that nanoparticles were non-toxic, thus confirming its promising therapeutical applications.

18.
Enferm Clin (Engl Ed) ; 33(2): 149-156, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36822472

RESUMO

We present the clinical case report on a 33-year-old woman who, after a perinatal death, presented a complicated grieving process. The aim was to apply an individualised care plan that enabled reestablishment of the woman's emotional balance and environment after an experience of perinatal death. During the first visit to her midwife, the Athens Insomnia, Continuity Bonds and Goldberg Anxiety and Depression scales were applied. Focussed assessment was made using the Gordon patterns and based on the nursing approach described in the Dysfunctional Bereavement Theory. Six International NANDA diagnostic labels were identified (maladaptative grieving, insomnia, hopelessness, ineffective mothering process, moral distress and anxiety), and these were prioritised using clinical network reasoning, using the Outcome Present State Test (OPT) model, observing the relationships between the labels, diagnoses and identifying how they affected the rest. For each International NANDA diagnostic labels, the nursing outcomes were planned, along with the planned nursing interventions. The expected results included the description of the evaluation indicators using the Likert scales. Both results and interventions were agreed between the professional and the mother. The care plan raises the difficulty that nursing professionals face when attending to situations of complicated grief, and specifically, those associated with perinatal death. This situation makes key competencies necessary in training, as well as the need to find out about new nursing approaches.


Assuntos
Luto , Morte Perinatal , Distúrbios do Início e da Manutenção do Sono , Humanos , Gravidez , Feminino , Adulto , Pesar , Planejamento de Assistência ao Paciente
19.
Clin Chim Acta ; 542: 117273, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36863694

RESUMO

INTRODUCTION: Population-based fecal tests for colorectal cancer (CRC) screening have shown to reduce mortality thanks to the early detection of the disease. However, currently available fecal tests are limited in their sensitivity and specificity. Our aim is to look for volatile organic compounds in fecal samples as biomarkers for CRC detection. MATERIAL AND METHODS: Eighty participants were included; 24 had adenocarcinoma, 24 had adenomatous polyps and 32 presented no neoplasms. Fecal samples were collected 48 h preceding the colonoscopy from all participants, except CRC patient samples that were collected after 3-4 weeks from the colonoscopy. Magnetic headspace adsorptive extraction (Mag-HSAE) followed by thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) was performed on stool samples to identify volatile organic compounds as biomarkers. RESULTS: p-Cresol was significantly more abundant in the cancer samples (P < 0.001) with an area under the curve (AUC) of 0.85 (CI 95%; 0.737-0.953), having a sensitivity and specificity of 83% and 82%, respectively. In addition, 3(4H)-dibenzofuranone,4a,9b-dihydro-8,9b-dimethyl- (3(4H)-DBZ) was also more abundant in the cancer samples (P < 0.001) with an AUC of 0.77 (CI 95%; 0.635-0.905), sensitivity of 78% and specificity of 75%. When combined (p-cresol and 3(4H)-DBZ), the AUC was 0.86, sensitivity 87% and specificity 79%. p-Cresol also appeared to be promising as a biomarker for pre-malignant lesions with an AUC of 0.69 (CI 95%; 0.534-0.862), sensitivity 83% and specificity 63%, P = 0.045. CONCLUSIONS: Volatile organic compounds emitted from feces and determined by a sensitive analytical methodology (Mag-HSAE-TD-GC-MS), employing a magnetic graphene oxide as extractant phase, could be used as a potential screening technology for CRC and pre-malignant lesions.


Assuntos
Neoplasias Colorretais , Compostos Orgânicos Voláteis , Humanos , Compostos Orgânicos Voláteis/análise , Biomarcadores Tumorais/análise , Cresóis , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/patologia , Sensibilidade e Especificidade , Detecção Precoce de Câncer/métodos , Fezes/química
20.
Int J Nanomedicine ; 18: 6979-6997, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026534

RESUMO

Purpose: Cancer is one of the major causes of death worldwide affecting more than 19 million people. Traditional cancer therapies have many adverse effects and often result in unsatisfactory outcomes. Natural flavones, such as apigenin (APG), have demonstrated excellent antitumoral properties. However, they have a low aqueous solubility. To overcome this drawback, APG can be encapsulated in nanostructured lipid carriers (NLC). Therefore, we developed dual NLC encapsulating APG (APG-NLC) with a lipid matrix containing rosehip oil, which is known for its anti-inflammatory and antioxidant properties. Methods: Optimisation, physicochemical characterisation, biopharmaceutical behaviour, and therapeutic efficacy of this novel nanostructured system were assessed. Results: APG-NLC were optimized obtaining an average particle size below 200 nm, a surface charge of -20 mV, and an encapsulation efficiency over 99%. The APG-NLC released APG in a sustained manner, and the results showed that the formulation was stable for more than 10 months. In vitro studies showed that APG-NLC possess significant antiangiogenic activity in ovo and selective antiproliferative activity in several cancer cell lines without exhibiting toxicity in healthy cells. Conclusion: APG-NLC containing rosehip oil were optimised. They exhibit suitable physicochemical parameters, storage stability for more than 10 months, and prolonged APG release. Moreover, APG-NLC were internalised inside tumour cells, showing the capacity to cause cytotoxicity in cancer cells without damaging healthy cells.


Assuntos
Nanoestruturas , Neoplasias , Humanos , Apigenina , Lipídeos/química , Portadores de Fármacos/química , Nanoestruturas/química , Antioxidantes/química , Tamanho da Partícula , Neoplasias/tratamento farmacológico
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