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1.
Biomed Chromatogr ; 37(5): e5601, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36775344

RESUMEN

Polyamines are low molecular weight compounds that are present in all living organisms. They are related to the pathological processes, and have been studied as biomarkers for tumor progression, being analyzed in patients' biological fluids. However, polyamines can undergo degradation in serum samples, depending on storage conditions, which impairs their quantification in these matrices. In this work, capillary electrophoresis using indirect ultraviolet detection has been developed and applied to evaluate the stability of polyamines [cadaverine (Cad), putrescine (Put), spermine (Spm), and spermidine (Spd)] in human serum at different storage temperatures. By using this method, Cad, Put, Spm, and Spd were separated in less than 4 min. The range of the correlation coefficients was 0.993-0.998. The corresponding limits of detection and quantification were as follows (in mg L-1 ): Spm: 0.209 and 0.697; Spd: 0.165 and 0.549; Put: 0.189 and 0.632; Cad: 0.125 and 0.417. Besides, the coefficient of variation was lower than 1% for all analytes and the recovery was 92%-110%. The method was successfully applied for polyamines spiked in human serum samples from healthy people. The results showed that the degradation of polyamines was lower in samples stored in a freezer (-20°C).


Asunto(s)
Poliaminas , Espermidina , Humanos , Poliaminas/análisis , Poliaminas/metabolismo , Temperatura , Espermidina/metabolismo , Putrescina/metabolismo , Espermina/metabolismo , Cadaverina , Electroforesis Capilar/métodos
2.
J Pharm Biomed Anal ; 210: 114586, 2022 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-35032934

RESUMEN

Experimental mixture design was drawn to evaluated the effects of the interactions between water, methanol and ethyl acetate mixtures on the extraction efficiency of coumarin (1,2-benzopyrone) from Dipteryx odorata seeds. Solvents were defined considering those preferred as green solvents for natural products extraction. Ultrasonic-assisted extraction method developed was simple, fast, low cost and highly selective. Analyses were performed by reversed-phase liquid chromatography using acetonitrile/water (40:60 v/v) as mobile phase, a C18 column, and a diode-array detector at 274 nm. Results were evaluated in linear, quadratic, special cubic, and full cubic models. The Full cubic model showed the best extraction results with a total error of 3.67%. The optimal extraction point was obtained using 15% water, 20% methanol, and 65% ethyl acetate (v/v). Based on the Guide for the Expression of Uncertainty in Measurements and Monte Carlo simulations, the uncertainty expression presented deviations of 1.18 and 1.64, respectively, showing the reliability of the analytical method. D. odorata seeds are popularly used in the pharmaceutical, food, and cosmetic applications due to high content of coumarins. However, the yield of coumarins extraction depends on the proper choice of the extraction method and solvents. The ternary mixture was optimized and resulted in 3.82% coumarin (weight/seed), which, compared to literature, showed a good increase over that obtained using common solvents, without considering the mathematical modeling.


Asunto(s)
Dipteryx , Cromatografía Líquida de Alta Presión , Cumarinas , Reproducibilidad de los Resultados , Solventes
3.
Front Public Health ; 10: 899638, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36761330

RESUMEN

Occupational exposure to potentially toxic elements (PTEs) is a concerning reality of informal workers engaged in the jewelry production chain that can lead to adverse health effects. In this study, untargeted proteomic and metabolomic analyses were employed to assess the impact of these exposures on informal workers' exposome in Limeira city, São Paulo state, Brazil. PTE levels (Cr, Mn, Ni, Cu, Zn, As, Cd, Sn, Sb, Hg, and Pb) were determined in blood, proteomic analyses were performed for saliva samples (n = 26), and metabolomic analyses in plasma (n = 145) using ultra-high performance liquid chromatography (UHPLC) coupled with quadrupole-time-of-flight (Q-TOF) mass spectrometry. Blood PTE levels of workers, controls, and their family members were determined by inductively coupled plasma-mass spectrometry (ICP-MS). High concentration levels of Sn and Cu were detected in welders' blood (p < 0.001). Statistical analyses were performed using MetaboAnalyst 4.0. The results showed that 26 proteins were upregulated, and 14 proteins downregulated on the welder group, and thirty of these proteins were also correlated with blood Pb, Cu, Sb, and Sn blood levels in the welder group (p < 0.05). Using gene ontology analysis of these 40 proteins revealed the biological processes related to the upregulated proteins were translational initiation, SRP-dependent co-translational protein targeting to membrane, and viral transcription. A Metabolome-Wide Association Study (MWAS) was performed to search for associations between blood metabolites and exposure groups. A pathway enrichment analysis of significant features from the MWAS was then conducted with Mummichog. A total of 73 metabolomic compounds and 40 proteins up or down-regulated in welders were used to perform a multi-omics analysis, disclosing seven metabolic pathways potentially disturbed by the informal work: valine leucine and isoleucine biosynthesis, valine leucine and isoleucine degradation, arginine and proline metabolism, ABC transporters, central carbon metabolism in cancer, arachidonic acid metabolism and cysteine and methionine metabolism. The majority of the proteins found to be statistically up or downregulated in welders also correlated with at least one blood PTE level, providing insights into the biological responses to PTE exposures in the informal work exposure scenario. These findings shed new light on the effects of occupational activity on workers' exposome, underscoring the harmful effects of PTE.


Asunto(s)
Isoleucina , Plomo , Humanos , Leucina , Proteómica , Brasil , Valina
4.
Biomed Chromatogr ; 34(1): e4673, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31385327

RESUMEN

Cri du Chat or 5p minus (5p-) syndrome is characterized by a deletion located on the chromosome 5 short (-p) arm and has an incidence rate of 1 in 50,000 individuals worldwide. This disease manifests in disturbances across a range of systems biochemicals. Therefore, a targeted metabolomics analysis was evaluated in patients with 5p- syndrome to help unravel the biochemical changes that occur in this disease. Urine samples were collected from people of both sexes aged 1-38 years old and analyzed by ultra-performance liquid chromatography coupled to mass spectrometry. Student' statistical test, metabolomic pathway analysis and metabolite set enrichment analysis were applied to the data. Alterations of some amino acids and amine biogenics levels were found in Cri du Chat Syndrome individuals. The alteration of most of these metabolites is associated with energy recuperation and glycolysis. In general, we found the catabolism of some metabolic pathways to be affected in 5p- patients.


Asunto(s)
Síndrome del Maullido del Gato , Metabolómica/métodos , Adolescente , Adulto , Aminoácidos/orina , Aminas Biogénicas/orina , Niño , Preescolar , Cromatografía Líquida de Alta Presión , Síndrome del Maullido del Gato/metabolismo , Síndrome del Maullido del Gato/orina , Humanos , Lactante , Límite de Detección , Modelos Lineales , Redes y Vías Metabólicas , Metaboloma , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem , Adulto Joven
5.
Braz. J. Pharm. Sci. (Online) ; 56: e17560, 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1285514

RESUMEN

Urea's thermal instability and burning on sensitive skin can cause problems for cosmetic formulations. To overcome these drawbacks, urea was incorporated into ordered mesoporous silica (SBA-15). SBA-15 was synthesized using tetraethyl orthosilicate and Pluronic® P123 in an acid medium. Urea (20 wt.%) was incorporated into calcined SBA-15 by the incipient wetness impregnation method. Several techniques were used to characterize the samples. Skin hydration and transepidermal water loss were measured using Corneometer® CM 825 PC and Tewameter® 300 TM. Results showed that the structural properties of SBA-15Urea were similar to pure SBA-15, indicating that SBA-15 remained structured even after urea incorporation. Nitrogen physisorption data showed the volume and surface area of the pores in SBA-15Urea were much lower than those in SBA-15, demonstrating that urea was deposited inside the mesopores. In vivo moisturization studies revealed that SBA-15Urea was not able to reduce transepidermal water loss compared to the other products and control, while forming a non-occlusive surface film on the skin. We conclude that incorporation of urea in the pores of the inorganic SBA-15 matrix is a promising approach to enhancing its stability and providing a prolonged moisturizing effect.


Asunto(s)
Urea/análisis , Dióxido de Silicio/administración & dosificación , Piel/efectos de los fármacos , Fluidoterapia/efectos adversos
6.
Biomed Res Int ; 2018: 9875319, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30065948

RESUMEN

Diacetyl is a flavoring that imparts a buttery flavor to foods, but the use or exposure to diacetyl has been related to some diseases. We investigated the effect of oral intake of diacetyl in male and female C57/Bl mice. We performed a target metabolomics assay using ultraperformance liquid chromatography paired with triple quadrupole mass spectrometry (UPLC-MS/MS) for the determination and quantification of plasmatic metabolites. We observed alterations in metabolites present in the urea and tricarboxylic acid (TCA) cycles. Peroxynitrite plasmatic levels were evaluated by a colorimetric method, final activity of superoxide dismutase (SOD) was evaluated by an enzymatic method, and mouse behavior was evaluated. Majority of the assay showed differences between control and treatment groups, as well as between genders. This may indicate the involvement of sex hormones in the regulation of a normal metabolic profile, and the implication of sex differences in metabolite disease response.


Asunto(s)
Diacetil/farmacología , Aromatizantes/farmacología , Metabolómica , Animales , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Femenino , Masculino , Ratones , Espectrometría de Masas en Tándem
7.
J Pharm Biomed Anal ; 140: 137-145, 2017 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-28351018

RESUMEN

Cri-du-chat syndrome (CDCS) is a rare innate disease attributed to chromosome 5p deletion characterized by a cat-like cry, craniofacial malformation, and altered behavior of affected children. Metabolomic analysis and a chemometric approach allow description of the metabolic profile of CDCS as compared to normal subjects. In the present work, UHPLC/MS was employed to analyze blood samples withdrawn from CDCS carriers (n=18) and normal parental subjects (n=18), all aged 0-34 years, aiming to set up a representative CDCS profile constructed from 33 targeted amino acids and biogenic amines. Methionine sulfoxide (MetO) was of particular concern with respect to CDCS redox balance. Increased serotonin (3-fold), methionine sulfoxide (2-fold), and Asp levels, and a little lower Orn, citrulline, Leu, Val, Ile, Asn, Gln, Trp, Thr, His, Phe, Met, and creatinine levels were found in the plasma of CDCS patients. Nitrotyrosine and Trp did not differ in normal and CDCS individuals.The accumulated metabolites may reflect, respectively, disturbances in the redox balance, deficient purine biosynthesis, and altered behavior, whereas the amino acid abatement in the latter group may affect the homeostasis of the urea cycle, citric acid cycle, branched chain amino acid synthesis, Tyr and Trp metabolism and amino acid biosynthesis. The identification of enzymatic deficiencies leading to the amino acid burden in CDCS is further required for elucidating its molecular bases and eventually propose specific or mixed amino acid supplementation to newborn patients aiming to balance their metabolism.


Asunto(s)
Síndrome del Maullido del Gato , Secuencia de Aminoácidos , Aminoácidos , Aminas Biogénicas , Humanos , Fragmentos de Péptidos
8.
J Pharm Biomed Anal ; 125: 408-14, 2016 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-27131151

RESUMEN

The application of Design of Experiments (DoE) to the determination of optimum conditions for an extraction process relies on the correct selection of mathematical models. The linear model is the one typically used; however, in some cases it does not always have superior performance, ignoring the real nature of the data and its appropriate descriptive model. In order to evaluate the extraction efficiency of isorhamnetin-3-O-rutinoside from flowers of Calendula officinalis L. a multivariate factorial analysis was used. Simulations were conducted using linear, quadratic, full cubic and special cubic models. A Simplex-Centroid design was chosen as it delivered greater precision with only minor errors versus other models tested. Analyses were performed by capillary zone electrophoresis using sodium tetraborate buffer (40mmolL(-1), pH 9.4) containing 10% methanol. The detection was linear over a range of 8.0-50.0mgL(-1) (r(2)=0.996), and the limits of detection (LOD) and quantification (LOQ) for isorhamnetin-3-O-rutinoside were 3.44mgL(-1) and 11.47mgL(-1), respectively. The full cubic model showed the best extraction results, with an error of 3.40% compared to analysis of variance, and a determination coefficient of 0.974. The difference between the responses at the reference point, calculated by the model, and the experimental response, varies around 2.72% for full cubic model. Comparison of the four models showed the full cubic model was the most appropriate one, allowing greater efficiency in the extraction of isorhamnetin-3-O-rutinoside. Selection of the model made it possible to obtain a 60% increase in sensitivity compared to the linear model.


Asunto(s)
Calendula/química , Disacáridos/aislamiento & purificación , Flavonoides/aislamiento & purificación , Límite de Detección , Reproducibilidad de los Resultados
9.
Braz. j. pharm. sci ; 52(1): 69-76, Jan.-Mar. 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-789089

RESUMEN

ABSTRACT Aiming to alter and/or improve permeation of active compounds in the skin, many strategies have been developed, including biophysical methods. One of the physical absorption techniques, currently known as Cryo Laser Phoresis (CLP), consists of an apparatus that emits radiation on polar or nonpolar molecules of the active substance, resulting in faster penetration when in comparison to the standard topical application. The goal of this work was to evaluate the efficacy of a method that proposes to increase cutaneous permeation of diclofenac sodium by using CLP technique. The influence on permeation was evaluated ex vivo, using Franz cell and human skin obtained from cosmetic surgery. The results were evaluated using statistical methods and data exploratory analysis: clusters, k-means and Principal Component Analysis. The results showed a larger increase in the concentration of diclofenac sodium in the dermis with the use of laser. In all samples (with or without laser application) it was observed that skin surface showed an amount of diclofenac sodium and that there was no active passage to the receptor liquid, suggesting that diclofenac sodium was not absorbed. These results indicate that CLP, when used under the conditions described in this study, is able to increase diclofenac sodium penetration and its retention into deeper layers.


RESUMO No sentido de alterar e/ou melhorar a penetração de substâncias na pele, diversas estratégias têm sido desenvolvidas, variando desde a aplicação de novos veículos e ativos encapsulados, até equipamentos que atuam por métodos biofísicos. Uma das técnicas de absorção física, atualmente conhecida como Crio Laser Forese (CLF), consiste em um aparato que emite radiação sobre moléculas polares ou apolares da substância ativa, tornando sua penetração mais rápida, se comparada à administração tópica comum. O objetivo deste trabalho foi avaliar a eficácia de um método que propõe aumentar a permeação cutânea do diclofenaco de sódio incorporado a um gel, por meio do uso da CLF. A influência sobre a permeação foi avaliada ex vivo, utilizando célula de Franz e pele humana obtida de cirurgia plástica. Os resultados foram balizados mediante aplicação de métodos estatísticos e análise exploratória de dados: clusters, k-means e Análise por Componentes Principais. Os resultados demonstraram aumento na concentração do diclofenaco de sódio na derme com o uso do laser. Em todas as amostras (com ou sem aplicação de laser), observou-se, uma quantidade de diclofenaco de sódio na superfície da pele e que não houve passagem de ativo para o líquido do receptor, sugerindo que o diclofenaco de sódio não foi absorvido. Estes resultados indicam que CLF usada sob as condições descritas neste estudo é capaz de aumentar a penetração do diclofenaco de sódio e sua retenção em camadas mais profundas da pele.


Asunto(s)
Diclofenaco/farmacocinética , Rayos Láser , Piel/efectos de los fármacos , Fármacos Dermatológicos/farmacocinética
10.
Anal Chem ; 75(15): 3853-8, 2003 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-14572053

RESUMEN

A new microfabrication process based on a xerographic process is described. A laser printer is used to selectively deposit toner on a polyester film, which is subsequently laminated against another polyester film. The toner layer binds the two polyester films and allows the blank regions to become channels for microfluidics. These software-outlined channels are approximately 6 microm deep. Approximately twice this depth is obtained by laminating two printed films. The resulting devices were not significantly damaged after 24 h of exposure to aqueous solutions of H3PO4, NaOH, methanol, acetonitrile, or sodium dodecyl sulfate. Electric tests with an impedance analyzer and microchannels filled with KCl solution demonstrated that (1) wide channels suffer from deformation of the top and bottom walls due to the lamination of the polyester films and (2) the toner walls are somewhat porous. Although these drawbacks limit the maximum width of a channel and the minimum distance between two channels, the process is an attractive option to other expensive, laborious, and time-consuming methods for microchannels fabrication. The process has been used to implement devices for electrospray tip and capillary electrophoresis with contactless conductivity detection.

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