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1.
Sci Total Environ ; 565: 795-803, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27102275

RESUMO

Commercial stabilized slurry of zero-valent iron nanoparticles (nZVI) as well as laboratory-synthesized polymer-stabilized NZVI nanoparticles were used for lindane (γ-hexachlorocyclohexane) degradation studies in aqueous solution. In the present study, polymer-stabilized iron nanoparticles were stabilized using polyethylene glycol (PEG, Mn ~400 and ~950-1050) and polytetrahydrofuran (PTHF, Mn ~650). To study the effectiveness of the different nanoparticles, a quantitative monitorization of lindane degradation by using solid-phase extraction (SPE) and a qualitative measurement of generated volatile by-products by headspace-solid phase microextraction (HS-SPME) followed by GC/MS were carried out. The obtained data were compared and contrasted with the results obtained in previous work. Results showed that the nanoparticles studied in this work possess superior dechlorination performance compared with previous observations. The freshly prepared Fe(0)-PEG400, Fe(0)-PEG1050 and Fe(0)-PTHF exhibited high reactivity during the dechlorination process of lindane in a very short time. The results obtained with the synthesized nanoparticles were similar to those obtained with commercial nanoparticles. However, in all cases reactivity decreased at reaction's late stage. Degradation of lindane by the studied nanoparticles removed 99.9% of the lindane initial concentration after 72h, except for Fe(0)-PTHF nanoparticles, for which the reaction stopped after 5min. In all cases, the reaction followed a second order kinetics. Finally, comparing the results from this study with our previous work, where different nature polymers were considered (Fe(0)-CMC, Fe(0)-PAA and Fe(0)-PAP), more gradual degradation profile of lindane was observed for Fe(0)-PAA and Fe(0)-CMC. It should be noted that in the present case, the reaction of lindane was speeded up with commercial and Fe(0)-PEG nanoparticles. Nevertheless, in the later case, the composition of by-products was affected by the presence of partially degraded intermediates. Taking into account the current technologies, the high removal rates obtained and the acceptable degradation times required, the proposed technology is suitable for its aimed purpose.


Assuntos
Hexaclorocicloexano/química , Ferro/química , Nanopartículas Metálicas/química , Polieletrólitos/química , Poluentes Químicos da Água/química , Inseticidas/química
2.
Clin Genet ; 90(2): 171-6, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26857240

RESUMO

Emery-Dreifuss muscular dystrophy (EDMD) is a heterogeneous genetic disorder characterized by peripheral muscular weakness often associated with dilated cardiomyopathy. We characterize clinically a large family with a mutation in FHL1 gene (p.Cys255Ser). Penetrance was 44%, 100% for males and 18% for females. The heart was the main organ involved. Affected adult males had mild hypertrophy, systolic dysfunction and restriction with non-dilated ventricles. Carriers had significant QTc prolongation. The proband presented with resuscitated cardiac arrest. There were two transplants. Pathological study of explanted heart showed fibrofatty replacement and scarring consistent with arrhythmogenic cardiomyopathy and prominent left ventricular trabeculations. Myopathic involvement was evident in all males. Females had no significant neuromuscular disease. Mutations in FHL1 cause unclassifiable cardiomyopathy with coexisting EDMD. Prognosis is poor and systolic impairment and arrhythmias are frequent. Thrombopenia and raised creatine phosphokinase should raise suspicion of an FHL-1 disorder in X-linked cardiomyopathy.


Assuntos
Arritmias Cardíacas/genética , Cardiomiopatia Dilatada/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas com Domínio LIM/genética , Proteínas Musculares/genética , Distrofia Muscular de Emery-Dreifuss/genética , Mutação , Adolescente , Adulto , Idoso , Arritmias Cardíacas/complicações , Arritmias Cardíacas/patologia , Arritmias Cardíacas/cirurgia , Biomarcadores/sangue , Cardiomiopatia Dilatada/complicações , Cardiomiopatia Dilatada/patologia , Cardiomiopatia Dilatada/cirurgia , Criança , Pré-Escolar , Creatina Quinase/sangue , Análise Mutacional de DNA , Feminino , Expressão Gênica , Transplante de Coração , Humanos , Masculino , Pessoa de Meia-Idade , Distrofia Muscular de Emery-Dreifuss/complicações , Distrofia Muscular de Emery-Dreifuss/patologia , Distrofia Muscular de Emery-Dreifuss/cirurgia , Miocárdio/metabolismo , Miocárdio/patologia , Linhagem , Fatores Sexuais , Trombocitopenia/fisiopatologia , Remodelação Ventricular
3.
Anal Chim Acta ; 892: 105-14, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26388480

RESUMO

Establishing the approximate age of an ink entry from a questioned document is often a complicated task and a controversial issue in forensic sciences. Among the existing approaches, the analysis of solvents in ballpoint inks may be a useful parameter for determining the age of ink on paper. In recent years, several ink dating methods have been proposed. These methods have been based on the analysis of common ink solvents using gas chromatography/mass spectrometry (GC/MS) as the analytical platform. Despite these recent methods, several questions remain. The aim of this work was to develop an ink dating methodology (DATINK) for documents written by ballpoint pens based on the disappearance of volatile solvents from the ink entry. Multiple solid-phase microextraction (MHS-SPME) coupled to GC/MS was used to measure the solvents from ink entries made with four BIC(®) ballpoint pens. The ß parameter, the remaining fraction of the analyte in the system after one equilibration, corresponding to the successive extractions was considered for modelling a mathematical equation for later ink age dating. Preliminary tests of DATINK method showed that it was possible to detect the presence of ink solvents on documents up to the studied five years. The analyses of different real samples of known age were analyzed in terms of ß values, which provided a mean relative error of 21%. The proposed use of ß parameter for estimating the absolute age of ballpoint ink entries has shown promising results with a standard deviation of ß ranging from 0.002 to 0.004.

4.
Talanta ; 123: 207-17, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24725884

RESUMO

Headspace (HS) and headspace solid phase microextraction (HS-SPME) analysis by gas chromatography-mass spectrometry (GC/MS) have been found to be suitable methods for the analysis of volatile organic compounds. The objectives of this paper are to study the possibilities of multiple headspace extraction (MHE) for the quantitative determination of volatile compounds in mushroom samples and to compare the results obtained using three different sample treatment techniques. For this purpose, HS with two different injection techniques (pressure-loop system and gas-tight syringe autosampling system) and HS-SPME have been studied. Three processes were optimized for the analysis of 20 volatile compounds by experimental design technique based on Central Composite Design (CCD) and Full Factorial Design depending on the used methodology. Once the designs were finished, a trade off among optimum conditions for each compound analyzed was reached. At optimum conditions, appropriate extraction time and sample amount for the three techniques used were established. Finally, the methods were validated in terms of linearity, detection and quantitation limits and repeatability. The most suitable method was then applied to the quantitative analysis of seven mushroom samples. A detailed comparison of the analytical performance characteristics of HS and HS-SPME as sample treatment techniques for final GC/MS determination is given. In addition, MHE has been proved to be an adequate technique to avoid matrix effects in complex samples quantitation. Its applicability to the determination of volatile mushroom components, along with its limitations, is discussed in this work.


Assuntos
Agaricales/química , Odorantes/análise , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Reprodutibilidade dos Testes , Olfato , Compostos Orgânicos Voláteis/classificação , Compostos Orgânicos Voláteis/isolamento & purificação
5.
Chemosphere ; 93(7): 1324-32, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23972910

RESUMO

Zero-valent iron nanoparticles (NZVI) as well as polymer-stabilized nanoparticles were synthesized and used for lindane (γ-hexachlorocyclohexane) degradation in aqueous solution. To study the effectiveness of the different coated nanoparticles, simple and rapid analytical methods have been developed to measure and to detect lindane and its by-products. For the monitorization of lindane degradation solid-phase extraction (SPE) was used, while volatile by-products formation measurement was carried out by headspace-solid phase microextraction (HS-SPME) followed by GC/MS. The SPE-GC/MS method provides low detection limits (0.2 µg L(-1)), high recovery (above 95%) and it is a valuable tool for kinetic studies of the degradation process for each polymer used, while HS-SPME-GC/MS has proved to be an effective tool for the extraction and evaluation of volatile degradation by-products.


Assuntos
Hexaclorocicloexano/análise , Ferro/química , Nanopartículas/química , Poluentes Químicos da Água/análise , Cromatografia Gasosa-Espectrometria de Massas , Hexaclorocicloexano/química , Microextração em Fase Sólida , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química
6.
Talanta ; 100: 246-53, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23141333

RESUMO

A simple, easy-to-use, efficient and environmentally friendly method has been developed for the simultaneous analysis of nine pirethroid pesticides in water samples by the combination of hollow fibre-based liquid-phase microextraction (HF-LPME) and gas chromatography-mass spectrometry (GC/MS). For the developed method, nine pirethroid pesticides (esbiothrin, prallethrin, bifenthrin, tetramethrin, phenothrin, permethrin, cyfluthrin, cypermethrin and deltamethrin) were concentrated and well separated under optimal conditions. Several factors that influence the efficiency of HF-LPME were investigated and optimized by means of experimental design. The proposed method has good linearity in the concentration range of 10-400 µg L(-1) with correlation coefficients between 0.995 and 0.999. Overall enrichment factors for the optimized method ranged from 139 to 255 times except for cypermethrin and deltamethrin which ranged from 35 to 128. Detection and quantitation limits of the chromatographic method were in the range of 0.002-0.012 µg L(-1) and 0.003-0.026 µg L(-1) respectively, with RSD values between 4.2% and 18.4%. The recoveries varied in the range of 69.4%-122.7% except for cypermethrin and deltamethrin (17.5%-64.1%) with relative standard deviations between 1.0% and 24.0% for intra and inter-day experiments at different concentrations (0.1 µg L(-1), 0.5 µg L(-1), 1 µg L(-1)). The HF-LPME method optimized was applied to the analysis of three spiked real water samples with good results.

7.
Arch Soc Esp Oftalmol ; 83(12): 713-7, 2008 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-19085643

RESUMO

CASE REPORT: Fabry's disease is an illness produced by an alteration in the catabolism of the glycosphingolipids. We report ophthalmologic findings in 4 people, detected after 113 patient evaluations from an analytical, cardiological and genetic point of view. DISCUSSION: Fabry's disease is uncommon and shows variable ophthalmologic affectation. Some patients with Fabry's disease do not present ocular affectation, while, on the other hand, healthy carriers with important ocular alterations have been described. The deposit of glycosphingolipids produces affectation at the corneal, crystalline, vascular and retinal levels. The vascular alterations affect not only the veins but also the arteries, as we report in our patients.


Assuntos
Oftalmopatias/etiologia , Doença de Fabry/complicações , alfa-Galactosidase/genética , Idoso , Sequência de Carboidratos , Catarata/etiologia , Doenças da Túnica Conjuntiva/etiologia , Doenças da Córnea/etiologia , Técnicas de Diagnóstico Oftalmológico , Oftalmopatias/diagnóstico , Doença de Fabry/enzimologia , Doença de Fabry/genética , Glicoesfingolipídeos/análise , Glicoesfingolipídeos/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Linhagem , Vasos Retinianos/metabolismo , Vasos Retinianos/patologia
8.
Arch. Soc. Esp. Oftalmol ; 83(12): 713-718, dic. 2008. ilus
Artigo em Es | IBECS | ID: ibc-70394

RESUMO

Caso clínico: La enfermedad de Fabry es una enfermedad producida por una alteración en el catabolismo de los glucoesfingolípidos. Se muestran las alteraciones oftalmológicas de cuatro pacientes detectados tras evaluar desde el punto de vista analítico, cardiológico y genético a 113 enfermos. Discusión: La enfermedad de Fabry es una enfermedad infrecuente con afectación oftalmológica inconstante existiendo enfermos con Fabry sin afectación ocular y portadores sanos, con importantes alteraciones oculares. El depósito de glucoesfingolípidos produce afectación a nivel corneal, cristaliniano, vascular y retiniano. Las alteraciones vasculares afectan no sólo a las venas sino también a las arterias como mostramos en nuestros pacientes


Case report: Fabrys disease is an illness produced by an alteration in the catabolism of the glycosphingolipids. We report ophthalmologic findings in 4 people, detected after 113 patient evaluations from an analytical, cardiological and genetic point of view. Discussion: Fabry’s disease is uncommon and shows variable ophthalmologic affectation. Some patients with Fabry’s disease do not present ocular affectation, while, on the other hand, healthy carriers with important ocular alterations have been described. The deposit of glycosphingolipids produces affectation at the corneal, crystalline, vascular and retinal levels. The vascular alterations affect not only the veins but also the arteries, as we report in our patients (Arch Soc Esp Oftalmol 2008; 83: 713-718)


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Doença de Fabry/complicações , Doença de Fabry/diagnóstico , Doença de Graves/complicações , Doença de Graves/diagnóstico , Angiografia/métodos , alfa-Galactosidase , alfa-Galactosidase , alfa-Galactosidase/farmacocinética , alfa-Galactosidase/metabolismo , Esclerose/complicações , Esclerose/epidemiologia , Córnea/patologia , Córnea
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