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1.
J Chromatogr A ; 1712: 464468, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37926006

RESUMO

A microextraction technique based on ferrofluids was developed for the preconcentration and quantification of Remdesivir in human plasma samples. This method utilized a new type of magnetic colloids created by combining silica-coated magnetic particles with modified ionic liquid and natural hydrophobic deep eutectic solvent as the carrier liquid. The efficiency of the sorption and desorption steps was optimized using a chemometrics approach. Under the optimized conditions, the calibration curve exhibited linearity in the concentration range of 0.5 to 500.0 µg L-1, with a limit of detection and quantification of 0.2 and 0.5 µg L-1, respectively. The method precision was evaluated by assessing intra- and interday precision at three different analyte concentrations, yielding values of 8.9% and 16.8%, respectively. Moreover, the method accuracy fell within the range of 90.9% to 107.5%. This proposed method offers a green and environmentally friendly sample preparation technique for conducting pharmacodynamic, pharmacokinetic, and therapeutic drug monitoring studies of Remdesivir in biological fluids. Importantly, this technique eliminates the need for external energy sources or the use of dispersive solvents, providing a more efficient and sustainable approach.


Assuntos
Líquidos Iônicos , Microextração em Fase Líquida , Humanos , Solventes/química , Solventes Eutéticos Profundos , Cromatografia Líquida , Cromatografia Líquida de Alta Pressão/métodos , Microextração em Fase Líquida/métodos , Limite de Detecção
2.
Arch Physiol Biochem ; 129(4): 913-921, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33612031

RESUMO

CONTEXT: Proper nutrition and exercise are effective strategies to improve overall metabolic health in diabetic patients. OBJECTIVE: This study evaluated the effects of Nigella sativa (NS) supplementation during resistance training (RT) on some biochemical variables in type 2 diabetes patients. METHODS: Forty patients were assigned to groups: RT + NS (RN), NS, RT + placebo (RP), and control (CO). RT was performed and NS was consumed for 8 weeks. Blood samples were collected at rest immediately before and after the 8 week intervention. RESULTS: RT or NS by themselves reduced HOMA-IR, insulin, glucose, TG, TC, LDL, ESR, CRP, AST, ALT and ALP, and increased HDL and HOMA-S. The combination of RT and NS, rather than each intervention alone, had significant effects on reduction of HOMA-IR, insulin, ESR and CRP as well as increases in HDL, HOMA-ß/S. CONCLUSION: RT combined with NS is sometimes a better strategy compared to single interventions for improving diabetes related biomarkers in type 2 diabetic patients.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Nigella sativa , Treinamento Resistido , Humanos , Nigella sativa/metabolismo , Glicemia/metabolismo , Insulina , Inflamação , Fígado/metabolismo
3.
J Sep Sci ; 45(7): 1362-1373, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35138031

RESUMO

A sensitive method based on liquid chromatography combined with a diode array detector was developed and validated to simultaneously determine tamoxifen, and its active metabolites N-desmethyltamoxifen, 4-hydroxytamoxifen, and endoxifen in human plasma samples. The green and sustainable vortex-assisted dispersive liquid-phase microextraction technique based on the natural hydrophobic deep eutectic solvent was used for the extraction and preconcentration of the analytes. Chemometrics and multivariate analysis were used to optimize the independent variables including the type and volume of deep eutectic solvent, extraction time, and ionic strength. Under optimal conditions, calibration curves were linear in a suitable range with the lower limits of quantification (0.8-10.0 µg/L), which covered the relevant concentrations of the analytes in plasma samples for a clinical study. Intra- and interday precision evaluated at three concentrations for the analytes were lower than 8.2 and 12.1%, respectively. Accuracy was in the range of 94.9-104.7%. The applicability of the developed method on human plasma samples illustrated the range 45.1-72.8, 98.4-128.3, 0.9-1.2, and 2.7-6.1 µg/L for tamoxifen, N-desmethyltamoxifen, 4-hydroxytamoxifen, and endoxifen, respectively. The validated method can be effective for the pharmacokinetics, pharmacodynamics, and therapeutic drug monitoring studies of tamoxifen and its main metabolites in biological fluids.


Assuntos
Neoplasias da Mama , Sobreviventes de Câncer , Microextração em Fase Líquida , Neoplasias da Mama/tratamento farmacológico , Quimiometria , Cromatografia Líquida de Alta Pressão/métodos , Solventes Eutéticos Profundos , Feminino , Humanos , Limite de Detecção , Microextração em Fase Líquida/métodos , Solventes/química , Tamoxifeno
4.
J Bodyw Mov Ther ; 24(4): 386-394, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33218539

RESUMO

INTRODUCTION: Apart from mental disorders, other complications that have been reported in some patients with Post-Traumatic Stress Disorder (PTSD), include physical pain and being quick to fatigue, which can severely affect the patients' daily life. Therefore, this study aims to evaluate the relationship between PTSD and physical fatigue in people with PTSD. METHOD: 18 military men with (n = 9) and without PTSD (n = 9), with an age range of 45-60 years, volunteered to participate. They were randomly assigned into two groups: PTSD and non-PTSD groups. Recording of the surface electromyography (EMG) in a specific muscle was conducted twice in both groups, once at baseline and then again after a single session of fatiguing exercise. Data were analyzed by ANOVA with repeated measure (2✕2) at the significance level of 0.05. RESULTS: Results showed that there was a significant main effect of intervention on electrical activity and neural conduction variables in the PTSD group (p = 0.04, p = 0.02). There was also an effect of time for the both variables (P < 0.001). CONCLUSION: Stress disorders may affect the time to fatigue in PTSD patients and subsequently cause some difficulties in their daily life.


Assuntos
Transtornos de Estresse Pós-Traumáticos , Eletromiografia , Exercício Físico , Humanos , Masculino , Pessoa de Meia-Idade , Fadiga Muscular
5.
J Bodyw Mov Ther ; 24(3): 154-160, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32825982

RESUMO

BACKGROUND: With increasing age, non-alcoholic fatty liver disease is very common among women with low levels of physical activity. Nonlinear resistance training is one of the new methods to help patients who have low levels of physical activity. Curcumin is an herbal supplement that has anti-inflammatory effects. The present study aimed to examine the effects of nonlinear resistance training and curcumin supplementation on the liver structure and biochemical markers in obese older women with non-alcoholic fatty liver disease. METHODS: Forty-five obese women with non-alcoholic fatty liver disease were randomly assigned into resistance training (RT), curcumin supplement (C), resistance training with curcumin supplement (RTC), and placebo (P) groups. The RT and RTC groups received 12-weeks of nonlinear resistance training while the C and P groups had a normal sedentary lifestyle. Daily, the C and RTC groups received a curcumin capsule while the P and RT groups were given a placebo capsule. Blood sampling and ultrasonography were taken before and after the protocol. RESULTS: Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels significantly decreased in the RT and RTC groups (P ≤ 0.05) but not in the C and P groups (P > 0.05). Alkaline phosphatase (ALP), total bilirubin (TB) levels, platelet counts (PLT), and liver structure did not significantly change in all groups (P > 0.05). Resistance training alone and with curcumin supplementation could significantly improve liver function while taking curcumin alone did not have any significant effect on it. CONCLUSION: 12-week non-linear resistance training has beneficial effects on non-alcoholic fatty liver disease in older obese women.


Assuntos
Curcumina , Hepatopatia Gordurosa não Alcoólica , Treinamento Resistido , Idoso , Biomarcadores , Suplementos Nutricionais , Feminino , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico
6.
J Bodyw Mov Ther ; 23(2): 284-290, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31103109

RESUMO

OBJECTIVES: Autism Spectrum Disorder (ASD) is related to a dysfunction of central nervous system that most frequently appears at the age of three years old. There is no certain cure for this disorder; however, decreasing complications can produce positive life changes. Increasing physical activity is an appealing method for reducing behavioral disorders in ASD. Since Tai Chi Chuan training improves focus, attention to internal cues and balance, it seems to be an effective system for autistic children. MATERIALS & METHODS: 18 children with ASD in the age range between 6-12 years old were divided randomly into experimental and control groups. The experimental group participated in a six-week program of Tai Chi Chuan consisting of 18 sessions, limited to 60 min each. To assess motor skills, an M-ABC test was used during pre- and post-assessment. In order to analyze the data, dependent and independent T tests were used (with significance level of 0.05). RESULTS: Results showed a significant difference in the subscales of ball skills and balance performance (P < 0.05) and no significant difference in the manual agility scale (P > 0.05) between the two groups. CONCLUSION: According to the results, it may be concluded that forms of Tai Chi Chuan improve balance and motion coordination. Moreover, this training consists of slow motion workouts with strongly focused attention, which may lead to developed control of body motions with harmony and discipline. Therefore, Tai Chi Chuan training seems to be a helpful therapeutic program to reduce motor limitations, and these benefits can be transferred to daily life in autistic children.


Assuntos
Transtorno do Espectro Autista/terapia , Destreza Motora/fisiologia , Tai Chi Chuan/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Equilíbrio Postural/fisiologia
7.
Anal Bioanal Chem ; 410(2): 605-614, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29264676

RESUMO

A rapid, simple, and sensitive approach to the analysis of trihalomethanes (THMs) in swimming pool water samples has been developed. The main goal of this study was to overcome or to improve the shortcomings of conventional dispersive liquid-liquid microextraction (DLLME) and to maximize the realization of green analytical chemistry principles. The method involves a simple vortex-assisted microextraction step, in the absence of the dispersive solvent, followed by salting-out effect for the elimination of the centrifugation step. A bell-shaped device and a solidifiable solvent were used to simplify the extraction solvent collection after phase separation. Optimization of the independent variables was performed by using chemometric methods in three steps. The method was statistically validated based on authentic guidance documents. The completion time for extraction was less than 8 min, and the limits of detection were in the range between 4 and 72 ng L-1. Using this method, good linearity and precision were achieved. The results of THMs determination in different real samples showed that in some cases the concentration of total THMs was more than threshold values of THMs determined by accredited healthcare organizations. This method indicated satisfactory analytical figures of merit. Graphical Abstract A novel green microextraction technique for overcoming the challenges of conventional DLLME. The proposed procedure complies with the principles of green/sustainable analytical chemistry, comprising decreasing the sample size, making easy automation of the process, reducing organic waste, diminishing energy consumption, replacing toxic reagents with safer reagents, and enhancing operator safety.


Assuntos
Microextração em Fase Líquida/métodos , Piscinas , Trialometanos/análise , Poluentes Químicos da Água/análise , Halogenação , Limite de Detecção , Solventes , Trialometanos/isolamento & purificação , Água/análise , Poluentes Químicos da Água/isolamento & purificação
8.
Biol Trace Elem Res ; 176(2): 258-269, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27628100

RESUMO

Urine lead level is one of the most employed measures of lead exposure and risk. The urine samples used in this study were obtained from ten healthy male cyclists. Dispersive liquid-liquid microextraction combined with ultraviolet and visible spectrophotometry was utilized for preconcentration, extraction, and determination of lead in urine samples. Optimization of the independent variables was carried out based on chemometric methods in three steps. According to the screening and optimization study, 133 µL of CCl4 (extracting solvent), 1.34 mL ethanol (dispersing solvent), pH 2.0, 0.00 % of salt, and 0.1 % O,O-diethyl dithiophosphoric (chelating agent) were used as the optimum independent variables for microextraction and determination of lead. Under the optimized conditions, R 2 was 0.9991, and linearity range was 0.01-100 µg L-1. Precision was evaluated in terms of repeatability and intermediate precision, with relative standard deviations being <9.1 and <15.3 %, respectively. The accuracy was estimated using urine samples of cyclists as real samples and it was confirmed. The relative error of ≤5 % was considered significant in the method specificity study. The lead concentration mean for the cyclists was 3.79 µg L-1 in urine samples. As a result, the proposed method is a robust technique to quantify lead concentrations higher than 11.6 ng L-1 in urine samples.


Assuntos
Atletas , Chumbo/urina , Microextração em Fase Líquida , Adulto , Voluntários Saudáveis , Humanos , Masculino , Software , Espectrofotometria Ultravioleta , Adulto Jovem
9.
J Sep Sci ; 35(1): 107-13, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22102622

RESUMO

A novel approach for the sample pre-treatment and determination of eight phenolic compounds in environmental water samples has been developed by hyphenating solid-phase extraction (SPE) and liquid-phase microextraction (LPME) techniques based on solid organic drop combined with gas chromatography-mass spectrometry detection (GC-MS). After pre-concentration and purification of the sample through column containing 60 mg of ß-cyclodextrin-bonded silica particles as stationary phase, under the optimum conditions, LPME technique has been performed on the eluent solution. Under the selected conditions, limit of detection (LOD) of 0.002-0.04 µg/L (S/N=3), limit of quantification (LOQ) of 0.007-0.15 µg/L (S/N=10), pre-concentration factor of 752-3135 and linearity range of 0.01-25 µg/L have been obtained. A reasonable repeatability (RSD≤9.5%, n=5) with satisfactory coefficient of determination has been obtained between 0.9981 and 0.9997. The relative recoveries of the waste, sea, river and well water samples were higher than 79%.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Líquida/métodos , Fenóis/análise , Fenóis/isolamento & purificação , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Rios/química , Água do Mar/química , Dióxido de Silício/química , beta-Ciclodextrinas/química
10.
J Chromatogr Sci ; 49(6): 482-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21682999

RESUMO

A stir bar coated with ß-cyclodextrin-bonded-silica (CDS) as novel sorbent has been developed and used to analyze seven phenolic compounds in aqueous samples, followed by thermal desorption and gas chromatography-mass spectrometric detection. Significant parameters affecting sorption process such as the time and temperature of sorption and desorption, ionic strength, pH and stirring rate have been optimized and discussed. The coating has a high thermal stability up to 300°C and long application lifetime (80 times). The porous structure of CDS coating provides high surface area and allows high extraction efficiency. Under the selected conditions, linearity range of 0.1-400 µg/L, limit of quantifications of 0.08-3.3 µg/L and method detection limits of 0.02-1.00 µg/L have been obtained. A satisfactory repeatability (RSD ≤ 6.5, n = 7) with good linearity (0.9975 ≤ r(2) ≤ 0.9996) of results illustrated a good performance of the present method. The recovery of different natural water samples was higher than 81.5%.


Assuntos
Fracionamento Químico/métodos , Fenóis/isolamento & purificação , Sílica Gel/química , beta-Ciclodextrinas/química , Água Doce/química , Modelos Lineares , Águas Minerais , Fenóis/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Temperatura
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