Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
1.
BMC Oral Health ; 24(1): 628, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807113

RESUMO

BACKGROUND: The purpose of this study was to test how musical flow using baroque (BM) and classical era music (CM) as a non-pharmacological therapy can control anxiety and pain levels among patients undergoing IPI (Immediate post-extraction implants). METHODS: 78 patients who required an IPI were enrolled in this randomized clinical trial. Each patient was assigned to one of the three experimental groups with a simple randomization: Group I (n = 26) listened to BM; Group II (n = 27) listened to CM; and Group III (n = 25) did not listen to music and was the control group (C). The physiological dependent variables analyzed were systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR) and oxygen saturation (SpO2). The psychological dependent variable analyzed was modified dental anxiety scale (MDAS) and visual analogue scale (VAS), measured before and after surgery. In all cases, the level of statistical significance was set at p < 0.01. RESULTS: Statistically significant differences were found in the SBP decrease in the CM group (p = 0.001, CI = 1.9716-6.5840) and the BM group (p = 0.003, CI = 1.4450-6.4396). Anxiety levels during the intervention decreased in both groups that listened to music: BM group (p = 0.002, CI = 0.645-2.662) and CM group (p = 0.000, CI = 1.523-3.884). CONCLUSIONS: Patients undergoing IPI placement surgery can register lower levels of SBP when listening to BM and CM than patients who were not exposed to the musical flow, improving their anxiety levels.


Assuntos
Ansiedade ao Tratamento Odontológico , Musicoterapia , Humanos , Masculino , Feminino , Estudos Prospectivos , Musicoterapia/métodos , Pessoa de Meia-Idade , Ansiedade ao Tratamento Odontológico/prevenção & controle , Ansiedade ao Tratamento Odontológico/psicologia , Adulto , Carga Imediata em Implante Dentário/métodos , Música/psicologia , Frequência Cardíaca/fisiologia , Medição da Dor , Pressão Sanguínea/fisiologia , Idoso , Dor Pós-Operatória/etiologia
2.
J Agric Food Chem ; 71(42): 15842-15854, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37846851

RESUMO

A polyhydroxy methacrylate-based stationary reversed phase was used for the determination of coformulants in 20 plant protection products (PPPs). These samples were analyzed by liquid chromatography coupled to Q-Orbitrap high-resolution mass spectrometry (LC-Q-Orbitrap-HRMS) in full-scan MS and data-dependent acquisition (ddMS2) modes. A total of 92 coformulants were tentatively identified in these formulations by nontargeted and unknown analyses. Twelve out of them were quantified by analytical standards. The most concentrated coformulant was the anionic surfactant dodecylbenzenesulfonic acid, whose highest content was obtained in the Score 25 sample (6.87%, w/v). Furthermore, triethylene glycol monomethyl ether, 4-s-butyl-2,6-di-tert-butylphenol, 1-ethyl-2-pyrrolidone, sorbitan monostearate, 2,6-dimethylaniline, palmitamide, and N-lauryldiethanolamine were quantified for the first time in these products. Hence, the polyhydroxy methacrylate-based stationary phase increased the identification of new coformulants in PPPs, being complementary to conventional C18. This strategy could be applied in future studies to estimate potential coformulant residues from PPPs applied to crops.


Assuntos
Cromatografia Líquida , Cromatografia Líquida/métodos , Espectrometria de Massas , Cromatografia Líquida de Alta Pressão/métodos
4.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-485247

RESUMO

Equitable access to vaccines is necessary to limit the global impact of the coronavirus disease 2019 (COVID-19) pandemic and the emergence of new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants. In previous studies, we described the development of a low-cost vaccine based on a Newcastle Disease virus (NDV) expressing the prefusion stabilized spike protein from SARS-CoV-2, named NDV-HXP-S. Here, we present the development of next-generation NDV-HXP-S variant vaccines, which express the stabilized spike protein of the Beta, Gamma and Delta variants of concerns (VOC). Combinations of variant vaccines in bivalent, trivalent and tetravalent formulations were tested for immunogenicity and protection in mice. We show that the trivalent preparation, composed of the ancestral Wuhan, Beta and Delta vaccines, substantially increases the levels of protection and of cross-neutralizing antibodies against mismatched, phylogenetically distant variants, including the currently circulating Omicron variant.

5.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22270676

RESUMO

There is still a need for safe, efficient and low-cost coronavirus disease 2019 (COVID-19) vaccines that can stop transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here we evaluated a vaccine candidate based on a live recombinant Newcastle disease virus (NDV) that expresses a stable version of the spike protein in infected cells as well as on the surface of the viral particle (AVX/COVID-12-HEXAPRO, also known as NDV-HXP-S). This vaccine candidate can be grown in embryonated eggs at low cost similar to influenza virus vaccines and it can also be administered intranasally, potentially to induce mucosal immunity. We evaluated this vaccine candidate in prime-boost regimens via intramuscular, intranasal, or intranasal followed by intramuscular routes in an open label non-randomized non-placebo-controlled phase I clinical trial in Mexico in 91 volunteers. The primary objective of the trial was to assess vaccine safety and the secondary objective was to determine the immunogenicity of the different vaccine regimens. In the interim analysis reported here, the vaccine was found to be safe and the higher doses tested were found to be immunogenic when given intramuscularly or intranasally followed by intramuscular administration, providing the basis for further clinical development of the vaccine candidate. The study is registered under ClinicalTrials.gov identifier NCT04871737. Funding was provided by Avimex and CONACYT.

6.
J Sport Rehabil ; 31(4): 398-413, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35078147

RESUMO

OBJECTIVES: To evaluate the efficacy of 24 weeks of treatment with Mézières method in a Spanish elite second-division soccer team with low back pain (LBP), analyzing their state of back health, flexibility, pain, and steps speed. DESIGN: Double-blind randomized controlled trial. METHODS: A total of 20 players with LBP from the second soccer division league were allocated equally to the experimental and control groups (n = 10) as per selection criteria and participated in 2 different rehabilitation programs. The postural Mézières method was implemented in the experimental group, whereas the standard European treatment protocol for LBP was implemented in the control group. Both treatments had a twice weekly session of 40 minutes duration for 24 weeks consecutively with a follow-up in the fourth, 12th, and 24th weeks. RESULTS: Multivariate analysis of covariance with the baseline assessment as a covariance showed a significant difference between groups at the 12th and 24th weeks of the treatment for pain and back functionality. A relevant difference between the experimental and control groups was shown only at the 24th week of the treatment (P < .05) for back flexibility. A significant difference between groups was reported for the quality of life scale and steps speed at the 24th week of the treatment (P > .05). CONCLUSION: The Mézières method showed a positive effect in the elite soccer athletes with nonspecific chronic LBP and can be used as an alternative treatment.


Assuntos
Dor Lombar , Futebol , Atletas , Método Duplo-Cego , Humanos , Dor Lombar/terapia , Qualidade de Vida
7.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22269808

RESUMO

NDV-HXP-S is a recombinant Newcastle disease virus based-vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which expresses an optimized (HexaPro) spike protein on its surface. The vaccine can be produced in embryonated chicken eggs using the same process as that employed for the production of influenza virus vaccines. Here we performed a secondary analysis of the antibody responses after vaccination with inactivated NDV-HXP-S in a Phase I clinical study in Thailand. The SARS-CoV-2 neutralizing and spike binding activity of NDV-HXP-S post-vaccination serum samples was compared to that of matched samples from mRNA BNT162b2 (Pfizer) vaccinees. Neutralizing activity of sera from NDV-HXP-S vaccinees was comparable to that of individuals vaccinated with BNT162b2. Interstingly, the spike binding activity of the NDV-HXP-S vaccinee samples was lower than that of sera obtained from individuals vaccinated with the mRNA vaccine. This let us to calculate ratios between binding and neutralizing antibody titers. Samples from NDV-HXP-S vaccinees had binding to neutralizing activity ratios similar to those of convalescent sera suggesting a very high proportion of neutralizing antibodies and low non-neutralizing antibody titers. Further analysis showed that, in contrast to mRNA vaccination, which induces strong antibody titers to the receptor binding domain (RBD), the N-terminal domain, and the S2 domain, NDV-HXP-S vaccination induces a very RBD focused response with little reactivity to S2. This explains the high proportion of neutralizing antibodies since most neutralizing epitopes are located in the RBD. In conclusion, vaccination with inactivated NDV-HXP-S induces a high proportion of neutralizing antibodies and absolute neutralizing antibody titers comparable to those after mRNA vaccination.

8.
Foods ; 10(9)2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34574136

RESUMO

A method was developed for the determination of mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH) in edible oils, achieving similar limits of quantification than those obtained by online extraction methodologies, i.e., 0.5 mg/kg. The isolation of MOSH and MOAH was performed in a silver nitrated silica gel stationary phase prior to their analysis by gas chromatography-flame ionization detector (GC-FID). To improve the sensitivity, the simulated on-column injection method, using a suitable liner, was optimized. The method was validated at 0.5, 10.0 and 17.9 mg/kg, and recoveries ranged from 80 to 110%. Intra and inter-day precision were evaluated at the same levels, and relative standard deviation (RSD) was lower than 20%. The method was applied to a total of 27 samples of different types of oil previously analyzed in an accredited laboratory, detecting MOSH up to 79.2 mg/kg and MOAH up to 22.4 mg/kg.

9.
J Sport Rehabil ; 29(7): 913-919, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31711041

RESUMO

CONTEXT: One of the main reasons why athletes with a high physical condition suffer from low back pain disease is because they often participate in sports that involve disc compression movements during flexion, lifting loads, or torsion movement. OBJECTIVES: This study aims to examine the effectiveness of the postural treatment of the Mézières method on elite rhythmic gymnastics athletes with low back pain. DESIGN: Double-blind, randomized, controlled trial. SETTING: The sports hall of "Puente Tocinos," Murcia, Spain. PARTICIPANTS: Ninety gymnastics athletes were randomized into 2 parallel groups (intervention: n = 39; control: n = 51), of whom 98.9% were women (women = 89; man = 1). INTERVENTION: The Mézières method postural therapy was implemented. It lasted about 60 minutes in repeated sessions of 2 to 3 meetings per week by counting in overall 60 sessions during a 24-week period. MAIN OUTCOME MEASURES: Visual analog scale of pain, sit and reach flexibility test, Runtastic (pedometer performance android application), Roland-Morris Questionnaire for the physical disability, and the Health Status Questionnaire were used. RESULTS: The univariate analysis of variance and independent sample t test revealed a significant improvement in the intervention group concerning the visual analog scale pain assessment scale (P < .05, ηp2=.625), and, also, the between-groups effect size was high during the 24 sessions of treatment (d > 0.8) compared with the control one. The same situation persists even for Roland-Morris Questionnaire (P < .05, ηp2=.802), physical score (P < .05, ηp2=.613), mental score (P < .05, ηp2=.736), sit and reach flexibility test (P < .05, ηp2=.666), and Runtastic performance (P < .05, ηp2=.790), where the between-groups effect size was high during the 24 sessions of treatment (d > 0.8). CONCLUSION: The Mézières method treatment performed on athletes with low back pain has caused positive effects on all the outcomes analyzed compared with the ones of control group.


Assuntos
Traumatismos em Atletas/fisiopatologia , Traumatismos em Atletas/terapia , Terapia por Exercício/métodos , Ginástica/lesões , Dor Lombar/fisiopatologia , Dor Lombar/terapia , Adolescente , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Medição da Dor , Inquéritos e Questionários , Adulto Jovem
10.
J Orthop Surg Res ; 14(1): 278, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31462250

RESUMO

BACKGROUND: Debridement and irrigation with prosthetic retention followed by antibiotic therapy (DAIR) is one of the treatments of choice in acute infections after a total knee arthroplasty. However, the success rate varies widely in the literature, depending on several factors such as comorbidities of the patient, duration of infection, and microorganisms involved. The goal of this study was to assess the outcomes of this therapeutic option and to identify possible predictors of the result. METHODS: We retrospectively reviewed cases of acute postoperative (≤ 3 months from index procedure) and acute hematogenous periprosthetic knee infections treated with DAIR at our hospital between 2004 and 2016. Overall, 26 knees were included, with a mean age of 73.4 years. Several variables related to patient characteristics, infection type, and surgery were examined to evaluate their influence on outcome, and functional and radiographic outcome were assessed. The mean follow-up was 41 months. A descriptive analysis was carried out on the collected data, and a univariate analysis was performed with the objective of searching for influential factors in the resolution of the infection using the chi-square nonparametric test in the case of the categorical variables and the Wilcoxon test for the continuous ones. Moreover, univariate cox regression analysis was performed. RESULTS: The overall success rate was 77% at the last follow-up, recording a significantly greater cure in acute infections (93% acute vs 58% acute hematogenous, p = 0.03). The infections in which the Staphylococcus aureus was isolated had a significantly lower cure rate, with only 33% of success, compared to 82% of the non-aureus microorganisms (p <  0.05). CONCLUSIONS: The present study shows a considerable cure rate in the treatment of acute knee infections through DAIR, although patient comorbidities, type of infection, and causative microorganism should be considered for decision-making.


Assuntos
Antibacterianos/administração & dosagem , Artroplastia do Joelho/efeitos adversos , Desbridamento/métodos , Retenção da Prótese/métodos , Infecções Relacionadas à Prótese/terapia , Idoso , Idoso de 80 Anos ou mais , Artroplastia do Joelho/tendências , Desbridamento/tendências , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Retenção da Prótese/tendências , Infecções Relacionadas à Prótese/diagnóstico por imagem , Resultado do Tratamento
11.
J Agric Food Chem ; 67(4): 1284-1291, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30636415

RESUMO

In this study, several calystegines (A3, A5, B1, B2, B3, B4, and C1) were determined in tomato. A simple extraction followed by a derivatization step with silylating agents was performed prior to their analysis by gas chromatography coupled to high resolution mass spectrometry (GC-HRMS-Q-Orbitrap), which allowed the monitoring of several ions at accurate mass. The validation of the method has provided suitable values of linearity, trueness (73.7-120.0%), and precision (≤20.0%, except for calystegines B3 and B4 at 0.5 mg/kg). The limit of quantitation was set at 0.5 mg/kg for all analytes. The validated method was successfully applied to the analysis of nine different tomato varieties, and calystegines A3, A5, B2, and C1 were found at concentrations ranging between 0.65 mg/kg (C1) and 12.47 mg/kg (B2). Tomato varieties were classified according to their calystegines content by applying an analysis of variance (ANOVA).


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Extratos Vegetais/química , Solanum lycopersicum/química , Tropanos/química , Análise de Variância , Solanum lycopersicum/classificação
12.
J Agric Food Chem ; 67(4): 1302-1311, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30618256

RESUMO

A comprehensive fingerprinting strategy for golden rum classification considering different categories such as fermentation barrel, raw material, and aging is provided, using a metabolomic fingerprinting approach. A nontarget fingerprinting of 30 different rums using liquid chromatography coupled to high-resolution mass spectrometry (Exactive Orbitrap mass analyzer, LC-HRMS) was applied. Principal component analysis (PCA) was used to assess the overall structure of the data and to identify potential outliers. Different chemometric analyses such as partial least-squares discriminant analysis (PLS-DA) were used. A variable importance in projection (VIP) selection method was applied to identify the most significant markers that allow group separation. Compounds related to aging and fermentation processes such as furfural derivates (e.g., hydroxymethylfurfural) and sugars (e.g., glucose, mannitol) were found as the most discriminant compounds (VIP threshold value >1.5). Suitable separation according to selected categories was achieved, and a classification ability of the models of close to 100% was achieved.


Assuntos
Bebidas Alcoólicas/análise , Técnicas de Química Analítica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Metabolômica/métodos , Bebidas Alcoólicas/classificação , Análise Discriminante , Análise de Componente Principal , Controle de Qualidade
14.
J AOAC Int ; 2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30305207

RESUMO

Background: Automated methods are needed for the reliable determination of xenobiotics in environmental samples. Objective: Optimization and application of an automated method for the ultra-trace analysis of 34 organic contaminants including polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), organochlorinated (OCPs), and organophosphorus pesticides (OPPs) in sediment samples have been performed. Methods: Automated method based on headspace solid-phase microextraction (SPME) coupled to GC-high-resolution MS (GC-HRMS) for the ultra-trace analysis of the targeted compounds has been developed. Conclusions: Suitable validation parameters in terms of linearity, trueness, selectivity, intraday and interday precision, LODs, and LOQs were obtained. Relative recovery values between 70 and 120% were achieved for all compounds (concentration levels assayed 1 and 10 µg/kg). RSD values were always lower than 25% for intra- and interday precision, and LODs and LOQs were 0.1 and 1.0 µg/kg, respectively, for all analytes. Highlights: The proposed method was applied to the analysis of sediments collected in Andalusia, Spain, and Poland, finding PCB 18 in one sample (15.9 µg/kg) and p,p'-DDE in several samples at concentrations ranging from 27.6 to 297.2 µg/kg.

15.
Orthopedics ; 40(1): 38-42, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27648577

RESUMO

Tear of the quadriceps tendon after revision or primary total knee arthroplasty is a rare complication, but when it occurs, this injury has serious functional consequences. In complete tears, the outcome of direct repair is unpredictable, and several authors recommend that the suture should be reinforced. Several techniques have been described, including the use of autografts, allografts, and synthetic mesh. The goal of this study was to assess the outcomes of a reconstruction technique augmented with synthetic mesh. A retrospective study was performed involving 3 patients who had chronic partial quadriceps tendon tear after total knee revision. In 2 cases, proximal quadriceps release was performed. When conservative management failed, surgical reconstruction with suture reinforced with synthetic mesh was attempted. The knee was immobilized in full extension for 6 weeks after the surgical procedure. A minimum follow-up of 12 months was required to assess results. All reconstructions showed clinical success at a mean follow-up of 19 months. Mean Knee Society Score improved from 55.7 to 87.3, with average postoperative extensor lag of 3.3° (range, 0°-10°). The mean visual analog scale pain score was 2.3 (range, 0-4). No complications were reported. Synthetic mesh has previously been shown to be an effective treatment for patellar tendon repairs after total knee replacement, but there have been few articles on quadriceps rupture. Surgical reconstruction with synthetic mesh is a viable option that provides good functional outcomes in chronic quadriceps tendon rupture after total knee arthroplasty. [Orthopedics. 2017; 40(1):38-42.].


Assuntos
Artroplastia do Joelho/efeitos adversos , Ligamento Patelar/lesões , Procedimentos de Cirurgia Plástica/métodos , Telas Cirúrgicas/efeitos adversos , Traumatismos dos Tendões/etiologia , Idoso , Feminino , Humanos , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/cirurgia , Ligamento Patelar/cirurgia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Próteses e Implantes/efeitos adversos , Músculo Quadríceps/lesões , Músculo Quadríceps/cirurgia , Estudos Retrospectivos , Ruptura Espontânea/etiologia , Ruptura Espontânea/cirurgia , Suturas/efeitos adversos , Traumatismos dos Tendões/cirurgia , Resultado do Tratamento
16.
Opt Express ; 24(13): 14159-71, 2016 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-27410574

RESUMO

An auto-referenced interferometric method for calibrating phase modulation of parallel-aligned liquid crystal (PAL) spatial light modulators (SLM) is described. The method is experimentally straightforward, robust, and requires solely of a collimated beam, with no need of additional optics. This method uses the SLM itself to create a tilted plane wave and a reference wave which mutually interfere. These waves are codified by means of a binary diffraction grating and a uniformly distributed gray level area (piston) into the SLM surface. Phase shift for each gray level addressed to the piston section can then be evaluated. Phase modulation on the SLM can also be retrieved with the proposed method over spatially resolved portions of the surface. Phase information obtained with this novel method is compared to other well established calibration procedures, requiring extra elements and more elaborated optical set-ups. The results show a good agreement with previous methods. The advantages of the new method include high mechanical stability, faster performance, and a significantly easier practical implementation.

17.
Food Chem ; 201: 59-63, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26868548

RESUMO

An adequate knowledge about possible transformation of bioactive compounds in nutraceutical products during long storage is important in order to know potential modifications of this type of compounds. In this study, one year monitoring was performed in different types of nutraceutical products based on natural extracts (green tea, soy, royal jelly and grapes) observing the appearance of new bioactive compounds, which were not detected at the initial conditions, as well as the decrease of some of the detected compounds. To determine these transformation products, an analytical procedure based on high resolution mass spectrometry (Exactive-Orbitrap analyzer) was applied. It was noted that transformation products were detected after 3 months of storage in green tea and soy products, while 6 months were necessary to observe transformation products in royal jelly.


Assuntos
Suplementos Nutricionais/análise , Espectrometria de Massas/métodos , Compostos Fitoquímicos/análise , Extratos Vegetais/análise , Armazenamento de Alimentos , Glycine max/química , Chá/química
18.
J Pharm Biomed Anal ; 121: 151-160, 2016 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-26808064

RESUMO

Analysis of 11 commercial nutraceutical products obtained from ginkgo has been performed using ultra-high performance liquid chromatography coupled to single-stage Orbitrap high resolution mass spectrometry (UHPLC-Orbitrap-MS). The main phytochemicals present in these samples were detected and quantified, utilizing a database containing 65 compounds. Phytochemicals were extracted using a mixture of an aqueous solution of methanol:water (80:20, v/v) in two sequential solid-liquid extractions. Adequate validation parameters were obtained. The validated compounds exhibited suitable linearity with determination coefficients (R(2)) higher than 0.99, and intra and inter-day precision were lower than 17 and 22%, respectively. Limits of detection (LODs) and quantification (LOQs) were calculated, ranging from 2 to 10 µg L(-1), except for myricetin (LOD, 150 µg L(-1) and LOQ, 300 µg L(-1)). Results indicate that the amount of terpenoids greatly varies among samples, ranging from 1133 (C7) to 12706 mg kg(-1) (C11). This emphasizes the importance of improve quality control in ginkgo-based products. Moreover, retrospective analysis allowed the detection of some undesirable substances as ginkgolic acid in the samples evaluated.


Assuntos
Produtos Biológicos/análise , Produtos Biológicos/química , Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais/análise , Ginkgo biloba/química , Espectrometria de Massas/métodos , Limite de Detecção , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/química , Controle de Qualidade , Estudos Retrospectivos , Salicilatos/química
19.
J AOAC Int ; 98(5): 1186-98, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26525236

RESUMO

A rapid and sensitive multiresidue method was developed and validated for the determination of around 100 pesticides in dry samples (rice and wheat flour) by ultra-performance LC coupled to a triple quadrupole mass analyzer working in tandem mode (UPLC/QqQ-MS/MS). The sample preparation step was optimized for both matrixes. Pesticides were extracted from rice samples using aqueous ethyl acetate, while aqueous acetonitrile extraction [modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) method] was used for wheat flour matrixes. In both cases the extracts were then cleaned up by dispersive solid phase extraction with MgSO4 and primary secondary amine+C18 sorbents. A further cleanup step with Florisil was necessary to remove fat in wheat flour. The method was validated at two concentration levels (3.6 and 40 µg/kg for most compounds), obtaining recoveries ranging from 70 to 120%, intraday and interday precision values≤20% expressed as RSDs, and expanded uncertainty values≤50%. The LOQ values ranged between 3.6 and 20 µg/kg, although it was set at 3.6 µg/kg for the majority of the pesticides. The method was applied to the analysis of 20 real samples, and no pesticides were detected.


Assuntos
Farinha/análise , Análise de Alimentos/métodos , Oryza/química , Resíduos de Praguicidas/análise , Triticum/química , Acetatos/química , Acetonitrilas/química , Adsorção , Cromatografia Líquida/instrumentação , Cromatografia Líquida/métodos , Análise de Alimentos/instrumentação , Contaminação de Alimentos/análise , Humanos , Limite de Detecção , Variações Dependentes do Observador , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos , Solventes/química , Manejo de Espécimes/métodos , Espectrometria de Massas em Tandem/instrumentação , Espectrometria de Massas em Tandem/métodos , Água/química
20.
J Chromatogr A ; 1389: 133-8, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25748536

RESUMO

Retrospective analysis has been applied in different samples, including honey, meat, feed and nutraceutical products from ginkgo biloba, soya, royal jelly and green tea, with the aim of searching transformation products of pesticides and veterinary drugs, which were not included in an initial analysis. Generic extraction and analytical procedures based on high resolution mass spectrometry (Exactive-Orbitrap analyser was used) have been applied. All obtained data have been reprocessed and some compounds as anhydroerythromycin in honey and 3,5,6-trichloro-2-pyridinol in feed have been detected, demonstrating the applicability and the utility of the procedure. Advantages and disadvantages of retrospective approach have been highlighted.


Assuntos
Poluentes Ambientais/análise , Tecnologia de Alimentos/métodos , Mel/análise , Carne/análise , Praguicidas/análise , Drogas Veterinárias/análise , Espectrometria de Massas , Estudos Retrospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...