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1.
Food Res Int ; 137: 109358, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33233061

RESUMEN

Food contaminants are usually studied as isolated molecules, not considering the overall meal components. Notwithstanding, contaminants are not ingested individually, therefore their risks should be assessed in the context of the overall diet. In the present study the influence of three well known dietary patterns, Western (W), Mediterranean (M) and vegetarian (V), on the bioaccessibility and intestinal transport of polycyclic aromatic hydrocarbons (PAHs) (benzo[a]pyrene (BaP) and benzo[b]fluoranthene (BbF)), heterocyclic aromatic amines (HAAs) (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 2-Amino-9H-pyrido[2,3-b]indole (AAC)) and mycotoxins (MY) (aflatoxin B2 (AB2) and ochratoxin A (OTA)) was evaluated. Whole meals representative of W, M and V patterns were spiked with 100 µg kg-1 of each contaminant and subjected to the Infogest in vitro digestion method. Intestinal transport was performed using Caco-2 cells in apical/basolateral inserts. Contaminants were quantified by QuEChERS/HPLC/Fluorescence analysis. The dietary pattern itself influenced significantly the bioaccessibility of some contaminants, since higher bioaccessibility of HAAs (PhIP and AAC) was observed for V diet, while higher bioaccessibility of PAHs (BBF and BAP) and the MY (OTA) was observed for W diet. Concerning intestinal transport, the effect of the diet matrices was less noticed. Notwithstanding, AAC transport increased with W diet, while AB2s transport increased with the V diet. Regarding PAHs the three patterns either blocked (BbF) or reduced (BaP) the transport. Besides the well known nutritional, protective or deleterious effects of the different dietary patterns, the increased bioaccessibility or intestinal transport of some food contaminants, can have an additional influence on the global health impact.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Aminas , Benzo(a)pireno , Células CACO-2 , Cromatografía Líquida de Alta Presión , Humanos
2.
J Appl Microbiol ; 126(4): 1140-1148, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30735287

RESUMEN

AIMS: Aspergillus sp. are ubiquitous saprophytic fungi and their conidia easily inhaled. This is particularly important in immunocompromised patients, more susceptible to developing invasive aspergillosis. In addition to A. fumigatus sensu stricto, cryptic species, many resistant to antifungal drugs, have been associated with invasive infections, making it important to assess their presence and diversity in different environments. Therefore, the aim of this study was to assess the presence, diversity and susceptibility to antifungal drugs of airborne fungi. Moreover, in azole-resistant A. fumigatus sensu stricto isolates the presence of underlying molecular mechanisms of resistance was investigated. METHODS AND RESULTS: Eighty-four Aspergillus isolates were collected from the environment air in hospitals and the Water Treatment Plant. The use of molecular tools allowed to detect 12 different cryptic species, showing a prevalence of 21·4%. The majority of isolates (69·0%) belonged to A. fumigatus complex and 65·4% were A. fumigatus sensu stricto. Among these, 21·8% were resistant to itraconazole (ITZ), 38·2% to posaconazole and 87·3% to isavuconazole; none of them were resistant to voriconazole or amphotericin B. Sequencing of the cyp51A gene on the 12 A. fumigatus sensu stricto ITZ-resistant isolates revealed the presence of mutations. CONCLUSION: Our study reports a large number of environmental-resistant Aspergillus species, including A. fumigatus sensu stricto that display an important role in invasive fungal infections. None of the environmental isolates showed mutations on cyp51A gene related to azole resistance. SIGNIFICANT AND IMPACT OF THE STUDY: This study is the first assessment of molecular resistance mechanisms in A. fumigatus sensu stricto environmental isolates, in Portugal. Since TR34/L98H and TR46/Y121F/T289A cyp51A mutations were already reported in the clinical setting in Portugal (Monteiro et al. J Glob Antimicron Resist 13: 190-191, 2018; Pinto et al. Front Microbiol 9: 1656, 2018), and have been linked to environmental route, it is utmost importance to perform surveillance network for azole-resistant A. fumigatus.


Asunto(s)
Microbiología del Aire , Aspergillus fumigatus/efectos de los fármacos , Aspergillus fumigatus/genética , Aspergillus/efectos de los fármacos , Farmacorresistencia Fúngica , Itraconazol/farmacología , Antifúngicos/farmacología , Aspergillus/clasificación , Aspergillus/genética , Aspergillus/aislamiento & purificación , Aspergillus fumigatus/clasificación , Aspergillus fumigatus/aislamiento & purificación , Proteínas Fúngicas/genética , Pruebas de Sensibilidad Microbiana , Mutación , Portugal
3.
Chemosphere ; 161: 19-26, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27411032

RESUMEN

Water disinfection plays a crucial role in water safety but it is also a matter of concern as the use of disinfectants promotes the formation of disinfection by-products (DBPs). Haloacetic acids (HAAs) are one of the major classes of DBPs since they are frequently found in treated water, are ubiquitous, pervasive and have high water solubility, so a great concern emerged about their formation, occurrence and toxicity. Exposure to HAAs is influenced by consumption patterns and diet of individuals thus their bioavailability is an important parameter to the overall toxicity. In the current study the bioacessibility of the most representative HAAs (chloroacetic acid - MCAA, bromoacetic acid - MBAA, dichloroacetic acid - DCAA, dibromoacetic acid - DBAA, and trichloroacetic acid - TCAA) after simulated in vitro digestion (SIVD) in tap water and transport across Caco-2 monolayers was evaluated. Compounds were monitored in 8 points throughout the digestion phases by an optimized LC-MS/MS methodology. MCAA and MBAA were not bioaccessible after SIVD whereas DCAA, DBAA and TCAA are highly bioaccessible (85 ± 4%, 97 ± 4% and 106 ± 7% respectively). Concerning transport assays, DCAA and DBAA were highly permeable throughout the Caco-2 monolayer (apparent permeability and calculated fraction absorbed of 13.62 × 10(-6) cm/s and 90% for DCAA; and 8.82 × 10(-6) cm/s and 84% for DBAA), whereas TCAA showed no relevant permeability. The present results may contribute to efficient risk analysis studies concerning HAAs oral exposure from tap water taking into account the different biological behaviour of these chemically similar substances.


Asunto(s)
Acetatos/metabolismo , Permeabilidad de la Membrana Celular/efectos de los fármacos , Agua Potable/normas , Contaminantes Químicos del Agua/metabolismo , Purificación del Agua/métodos , Acetatos/análisis , Células CACO-2 , Ácido Dicloroacético/análisis , Ácido Dicloroacético/metabolismo , Desinfección , Agua Potable/química , Humanos , Espectrometría de Masas en Tándem , Ácido Tricloroacético/análisis , Ácido Tricloroacético/metabolismo , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua
4.
Genet Mol Res ; 13(1): 799-805, 2014 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-24615044

RESUMEN

We evaluated the efficacy of noninvasive fetal Rhesus D (RHD) genotyping from maternal plasma in a highly admixed population. Fifty-five blood samples from RhD-negative pregnant women from Brazil were processed for extraction of cell-free plasma DNA. Real-time PCR was performed to amplify segments of exons 5 and 7 from the RHD gene, as well as for detection of the SRY gene to confirm the presence of fetal DNA. Fetal genotyping results were compared with the RhD phenotype determined from newborn cord blood samples obtained at birth. Thirty-two samples were RHD-positive, 18 were RHD-negative and 5 were inconclusive due to amplification of only one RHD exon. In 43 samples, the fetal RHD genotype was compared to the neonatal RhD phenotype, and only one result was discordant, due to false-negative serology. There was one false SRY genotyping negative result. We conclude that noninvasive fetal RHD genotyping from maternal blood provides accurate results and suggests its viability as a clinical tool for the management of RhD-negative pregnant women in an admixed population.


Asunto(s)
Diagnóstico Prenatal , Sistema del Grupo Sanguíneo Rh-Hr/sangre , Brasil , Femenino , Feto , Genotipo , Humanos , Recién Nacido , Relaciones Materno-Fetales , Embarazo , Sistema del Grupo Sanguíneo Rh-Hr/genética
5.
J Agric Food Chem ; 59(16): 8742-53, 2011 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-21732693

RESUMEN

A simple, reliable, and sensitive gas chromatography-mass spectrometry method for the quantification of volatile and nonvolatile biogenic amines in Port wines and grape juices was developed and evaluated. The method was based on a previously reported two-phase derivatization procedure with isobutyl chloroformate in a toluene medium, which provides a quantitative reaction in 10 min. Following the derivatization step, the excess of reagent was eliminated by treatment with alkaline methanol. The derivatization procedure was performed directly on 1 mL of sample, avoiding any fastidious and time-consuming cleanup extraction steps. The method allows the simultaneous quantification of 22 amines, which can be found in wines: methylamine, dimethylamine, ethylamine, diethylamine, propylamine, isopropylamine, butylamine, isobutylamine, amylamine, isoamylamine, 2-methylbutylamine, hexylamine, pyrrolidine, piperidine, morpholine, 1,3-diaminopropane, putrescine, cadaverine, 1,6-diaminohexane, 2-phenylethylamine, histamine, and tyramine. Because of the fact that histamine and tyramine derivatives are degraded during the isobutyl chloroformate elimination step, the corresponding determination was made after removal of the excess of derivatizing reagent by evaporating an aliquot of the toluene layer obtained after the reaction. The presented method showed excellent analytical characteristics in what linearity, recovery, repeatability, and limit of detections were respected. It was used to assess the concentration of biogenic amines in juice grapes and Tawny and Vintage Port wines with different aging times. On the whole, the total content of amines in Port wines was low. Most of the amines found in wines have their origin in the raw material used for their elaboration, so the Port winemaking process is not prone to the production of this kind of compounds. Total biogenic amine contents have shown a decrease with the aging of both types of Port wines.


Asunto(s)
Aminas Biogénicas/análisis , Formiatos , Frutas/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Vitis/química , Vino/análisis , Bebidas/análisis , Factores de Tiempo
6.
Braz J Med Biol Res ; 40(3): 425-33, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17334541

RESUMEN

We assessed the neuropsychological test performances of 26 patients (mean age = 41.5 +/- 6.1 years; mean years of education = 9.8 +/- 1.8; 20 males) diagnosed with chronic occupational mercurialism who were former workers at a fluorescent lamp factory. They had been exposed to elemental mercury for an average of 10.2 +/- 3.8 years and had been away from this work for 6 +/- 4.7 years. Mean urinary mercury concentrations 1 year after cessation of work were 1.8 +/- 0.9 microg/g creatinine. Twenty control subjects matched for age, gender, and education (18 males) were used for comparison. Neuropsychological assessment included attention, inhibitory control, verbal and visual memory, verbal fluency, manual dexterity, visual-spatial function, executive function, and semantic knowledge tests. The Beck Depression Inventory and the State and Trait Inventory were used to assess depression and anxiety symptoms, respectively. The raw score for the group exposed to mercury indicated slower information processing speed, inferior performance in psychomotor speed, verbal spontaneous recall memory, and manual dexterity of the dominant hand and non-dominant hand (P < 0.05). In addition, the patients showed increased depression and anxiety symptoms (P < 0.001). A statistically significant correlation (Pearson) was demonstrable between mean urinary mercury and anxiety trait (r = 0.75, P = 0.03). The neuropsychological performances of the former workers suggest that occupational exposure to elemental mercury has long-term effects on information processing and psychomotor function, with increased depression and anxiety also possibly reflecting the psychosocial context.


Asunto(s)
Exposición por Inhalación/efectos adversos , Trastornos Mentales/inducido químicamente , Trastornos Mentales/etiología , Mercurio/toxicidad , Enfermedades Profesionales/inducido químicamente , Exposición Profesional/efectos adversos , Trastornos Psicomotores/inducido químicamente , Adulto , Atención/efectos de los fármacos , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Memoria/efectos de los fármacos , Trastornos Mentales/diagnóstico , Mercurio/orina , Persona de Mediana Edad , Pruebas Neuropsicológicas , Enfermedades Profesionales/diagnóstico , Trastornos Psicomotores/diagnóstico , Factores de Tiempo
7.
Braz. j. med. biol. res ; 40(3): 425-433, Mar. 2007. tab, graf
Artículo en Inglés | LILACS | ID: lil-441771

RESUMEN

We assessed the neuropsychological test performances of 26 patients (mean age = 41.5 ± 6.1 years; mean years of education = 9.8 ± 1.8; 20 males) diagnosed with chronic occupational mercurialism who were former workers at a fluorescent lamp factory. They had been exposed to elemental mercury for an average of 10.2 ± 3.8 years and had been away from this work for 6 ± 4.7 years. Mean urinary mercury concentrations 1 year after cessation of work were 1.8 ± 0.9 æg/g creatinine. Twenty control subjects matched for age, gender, and education (18 males) were used for comparison. Neuropsychological assessment included attention, inhibitory control, verbal and visual memory, verbal fluency, manual dexterity, visual-spatial function, executive function, and semantic knowledge tests. The Beck Depression Inventory and the State and Trait Inventory were used to assess depression and anxiety symptoms, respectively. The raw score for the group exposed to mercury indicated slower information processing speed, inferior performance in psychomotor speed, verbal spontaneous recall memory, and manual dexterity of the dominant hand and non-dominant hand (P < 0.05). In addition, the patients showed increased depression and anxiety symptoms (P < 0.001). A statistically significant correlation (Pearson) was demonstrable between mean urinary mercury and anxiety trait (r = 0.75, P = 0.03). The neuropsychological performances of the former workers suggest that occupational exposure to elemental mercury has long-term effects on information processing and psychomotor function, with increased depression and anxiety also possibly reflecting the psychosocial context.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Exposición por Inhalación/efectos adversos , Trastornos Mentales/inducido químicamente , Trastornos Mentales/etiología , Mercurio/toxicidad , Enfermedades Profesionales/inducido químicamente , Exposición Profesional/efectos adversos , Trastornos Psicomotores/inducido químicamente , Atención/efectos de los fármacos , Estudios de Casos y Controles , Memoria/efectos de los fármacos , Trastornos Mentales/diagnóstico , Mercurio/orina , Pruebas Neuropsicológicas , Enfermedades Profesionales/diagnóstico , Trastornos Psicomotores/diagnóstico , Factores de Tiempo
8.
Environ Toxicol Pharmacol ; 19(3): 523-9, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-21783522

RESUMEN

We evaluated vision loss in workers from fluorescent lamp industries (n=39) who had retired due to intoxication with mercury vapour and had been away from the work situation for several years (mean=6.32 years). An age-matched control group was submitted to the same tests for comparison. The luminance contrast sensitivity (CSF) was measured psychophysically and with the sweep visual evoked potential (sVEP) method. Chromatic red-green and blue-yellow CSFs were measured psychophysically. Colour discrimination was assessed with the Farnsworth-Munsell 100-hue test, Lanthony D-15d test and Cambridge Colour Vision Test. Patient data showed significantly lower scores in all colour tests compared to controls (p<.001). The behavioural luminance CSF of the patients was lower than that of controls (p<.001 at all frequencies tested). This result was confirmed by the electrophysiologically measured sweep VEP luminance CSF except at the highest frequencies-a difference that might be related to stimulus differences in the two situations. Chromatic CSFs were also statistically significantly lower for the patients than for the controls, for both chromatic equiluminant stimuli: red-green (p<.005) and blue-yellow (p<.04 for all frequencies, except 2 cycles per degree (cpd), the highest spatial frequency tested) spatial gratings. We conclude that exposure to elemental mercury vapour is associated with profound and lasting losses in achromatic and chromatic visual functions, affecting the magno-, parvo- and koniocellular visual pathways.

12.
J Agric Food Chem ; 48(4): 1096-100, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10775355

RESUMEN

A microsatellite DNA-based method for Vitis vinifera grape must authentication is presented. Five of the most important port wine producing grape cultivars (Tinta Roriz, Tinto Cão, Touriga Francesa, Touriga Nacional, and Tinta Barroca) were typed at four microsatellite loci described by Bowers et al. (Genome 1996, 39, 628-633) and Thomas and Scott (Theor. Appl. Genet. 1993, 86, 985-990). The corresponding 5 varietal musts and 26 must mixtures that result from the combination of the five varieties were also typed at the four loci. There were no differences between the corresponding leaf and varietal must profiles. All must combinations showed the expected band profiles corresponding to the sum of the varietal band profile components. Among the 26 must mixtures, 8 could be discriminated using the four loci.


Asunto(s)
Repeticiones de Microsatélite , Rosales/genética , ADN de Plantas/genética , Manipulación de Alimentos , Rosales/clasificación
13.
West J Med ; 172(4): 224-5, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10778364
14.
Arq Neuropsiquiatr ; 58(1): 32-8, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10770863

RESUMEN

Insomnia is one of the symptoms of inorganic mercury poisoning (IMP). The objective of this study is to analyze the chief psychological aspects in the adjustment of workers with chronic insomnia associated with IMP. For this purpose the Preventive Clinical Interview and the Ryad Simon Operational Adaptive Diagnostic Scale (Escala Diagnóstica Adaptativa Operacionalizada-EDAO) were utilized. Fifteen subjects with mean age of 40 years (10 males and 5 females) were studied. Nine were diagnosed with High Adaptive Inefficacy, five with Moderate Inefficient Adaptation and only one with Mild Inefficient Adaptation. Impairment occurred in four adaptive sectors: affective relationship, social-cultural, productivity and organic. Adaptive efficiency indicated that in all the 15 subjects studied the adaptive solutions were frustrating and led to psychic suffering and/or environmental conflict confirming the severity of the involvement in chronic IMP.


Asunto(s)
Adaptación Fisiológica , Adaptación Psicológica , Intoxicación por Mercurio/psicología , Enfermedades Profesionales/psicología , Trastornos del Inicio y del Mantenimiento del Sueño/psicología , Adulto , Enfermedad Crónica , Femenino , Humanos , Masculino , Intoxicación por Mercurio/complicaciones , Persona de Mediana Edad , Enfermedades Profesionales/inducido químicamente , Trastornos del Inicio y del Mantenimiento del Sueño/inducido químicamente
17.
Ann Intern Med ; 129(4): 335; author reply 336-7, 1998 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-9729192
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