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2.
Meat Sci ; 175: 108440, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33497852

RESUMO

Iberian pigs fed on acorns and pasture were slaughtered from January until March of 2018 and 2019. The meat from those Iberian pigs is a seasonal food that only can be found fresh, at the marketplace, during a limit period of the year. Selling frozen-thawed meat is a legal practice, but consumers must be informed about it on the product label. However, to declare as fresh meat, meat previously frozen, is one of the most frequent meat frauds. The present study compares the performance of two rather different Near Infrared Spectroscopy instruments, based on Fourier Transform and Linear Variable Filter technologies, for the in-situ detection of fresh and frozen-thawed acorns-fed Iberian pig loins using Partial Least Discriminant Analysis (PLS-DA). The performance of the models developed for both instruments offered a very high discriminant ability. Furthermore, the models showed consistent results and interpretation when were evaluated with several scalars and graphical methods.


Assuntos
Congelamento , Carne de Porco/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Animais , Análise Discriminante , Rotulagem de Alimentos , Alimentos Congelados , Carne de Porco/normas , Suínos
3.
Meat Sci ; 153: 86-93, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30913412

RESUMO

Conventional chemical analyses of meat products are time-consuming, expensive and destructive. The advantages of NIR spectroscopy are its speed, portability, suitability for both at-line and on-line analysis, low cost and the possibility of simultaneously measuring many different parameters in a large number of samples. The purpose of this study was to develop and validate calibrations for the prediction of moisture, protein and fat in Iberian pig pork loins using an FT-NIR instrument coupled to a 5-m fibre optic sensor head. The best equations obtained for intact loin in both modes of analysis (full and optimal spectral range) displayed Standard Error of Cross-Validation (RMSECV) of 1.06% and 1.09% and Determination Coefficient of Cross-Validation (RCV2) of 0.69 and 0.77 for fat: RMSECV of 0.87% and 0.77% and RCV2 of 0.67 and 0.73 for moisture; while for protein, the RMSECV values were 0.51% and 0.49% and the RCV2 values were 0.66 and 0.70.


Assuntos
Carne Vermelha/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Animais , Gorduras/análise , Análise de Fourier , Proteínas/análise , Sus scrofa , Água/química
4.
Oecologia ; 187(3): 811-823, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29704063

RESUMO

A trend of increasing woody plant density, or woody thickening, has been observed across grassland and woodland ecosystems globally. It has been proposed that increasing atmospheric [CO2] is a major driver of broad scale woody thickening, though few field-based experiments have tested this hypothesis. Our study utilises a Free Air CO2 Enrichment experiment to examine the effect of elevated [CO2] (eCO2) on three mechanisms that can cause woody thickening, namely (i) woody plant recruitment, (ii) seedling growth, and (iii) post-disturbance resprouting. The study took place in a eucalypt-dominated temperate grassy woodland. Annual assessments show that juvenile woody plant recruitment occurred over the first 3 years of CO2 fumigation, though eCO2 did not affect rates of recruitment. Manipulative experiments were established to examine the effect of eCO2 on above-ground seedling growth using transplanted Eucalyptus tereticornis (Myrtaceae) and Hakea sericea (Proteaceae) seedlings. There was no positive effect of eCO2 on biomass of either species following 12 months of exposure to treatments. Lignotubers (i.e., resprouting organs) of harvested E. tereticornis seedlings that were retained in situ for an additional year were used to examine resprouting response. The likelihood of resprouting and biomass of resprouts increased with lignotuber volume, which was not itself affected by eCO2. The presence of herbaceous competitors and defoliation by invertebrates and pathogens were found to greatly reduce growth and/or resprouting response of seedlings. Our findings do not support the hypothesis that future increases in atmospheric [CO2] will, by itself, promote woody plant recruitment in eucalypt-dominated temperate grassy woodlands.


Assuntos
Herbivoria , Plântula , Dióxido de Carbono , Ecossistema , Florestas , Solo
5.
Clin Genet ; 93(4): 762-775, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28892148

RESUMO

Smith-Kingsmore syndrome (SKS) OMIM #616638, also known as MINDS syndrome (ORPHA 457485), is a rare autosomal dominant disorder reported so far in 23 patients. SKS is characterized by intellectual disability, macrocephaly/hemi/megalencephaly, and seizures. It is also associated with a pattern of facial dysmorphology and other non-neurological features. Germline or mosaic mutations of the mTOR gene have been detected in all patients. The mTOR gene is a key regulator of cell growth, cell proliferation, protein synthesis and synaptic plasticity, and the mTOR pathway (PI3K-AKT-mTOR) is highly regulated and critical for cell survival and apoptosis. Mutations in different genes in this pathway result in known rare diseases implicated in hemi/megalencephaly with epilepsy, as the tuberous sclerosis complex caused by mutations in TSC1 and TSC2, or the PIK3CA-related overgrowth spectrum (PROS). We here present 4 new cases of SKS, review all clinical and molecular aspects of this disorder, as well as some characteristics of the patients with only brain mTOR somatic mutations.


Assuntos
Encéfalo/metabolismo , Megalencefalia/genética , Síndrome de Smith-Lemli-Opitz/genética , Serina-Treonina Quinases TOR/genética , Adolescente , Encéfalo/fisiopatologia , Proliferação de Células/genética , Criança , Classe I de Fosfatidilinositol 3-Quinases/genética , Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/fisiopatologia , Feminino , Humanos , Deficiência Intelectual/genética , Deficiência Intelectual/fisiopatologia , Masculino , Megalencefalia/diagnóstico por imagem , Megalencefalia/fisiopatologia , Mutação , Plasticidade Neuronal/genética , Proteínas Proto-Oncogênicas c-akt/genética , Síndrome de Smith-Lemli-Opitz/diagnóstico por imagem , Síndrome de Smith-Lemli-Opitz/fisiopatologia , Proteína 1 do Complexo Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética
6.
Ecotoxicol Environ Saf ; 147: 192-199, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28843190

RESUMO

The fate of mercury (Hg) in the soil-earthworm system is still far from being fully understood, especially regarding recurrent and challenging questions about the importance of the reactivity of exogenous Hg species. Thus, to predict the potential effect of Hg inputs in terrestrial ecosystems, it is necessary to evaluate separately the reactivity of the endogenous and exogenous Hg species and, for this purpose, the use of enriched stable isotope tracers is a promising tool. In the present work, earthworms (Lumbricus terrestris) were exposed to historically Hg contaminated soils from the Almadén mining district, Spain. The soils were either non-spiked, which contain only endogenous or native Hg naturally occurring in the soil, or spiked with isotopically enriched inorganic Hg (199IHg), representing exogenous or spiked Hg apart from the native one. The differential reactivity of endogenous and exogenous Hg in the soil conditioned the processes of methylation, mobilization, and assimilation of inorganic Hg by earthworms. Both endogenous and exogenous Hg species also behave distinctly regarding their bioaccumulation in earthworms, as suggested by the bioaccumulation factors, being the endogenous methylmercury (MeHg) the species more readily bioaccumulated by earthworms and in a higher extent. To the best of our knowledge, this work demonstrates for the first time the potential of enriched stable isotopes to study the effects of fresh Hg inputs in soil-earthworm systems. The findings of this work can be taken as a case study on the dynamics of Hg species in complex terrestrial systems and open a new door for future experiments.


Assuntos
Isótopos de Mercúrio/análise , Mercúrio/análise , Compostos de Metilmercúrio/metabolismo , Oligoquetos/metabolismo , Poluentes do Solo/análise , Solo/química , Animais , Mercúrio/metabolismo , Isótopos de Mercúrio/metabolismo , Metilação , Mineração , Poluentes do Solo/metabolismo , Espanha
8.
Artigo em Inglês | MEDLINE | ID: mdl-27093497

RESUMO

Mercury (Hg) is likely bound to large biomolecules (e.g. proteins) in living organisms, and in order to assess Hg metabolic pathways and possible toxicological effects, it is essential to study these Hg containing biomolecules. However, the exact nature of most metal binding biomolecules is unknown. Such studies are still in their infancy and information on this topic is scarce because the analysis is challenging, mainly due to their lability upon digestion or extraction from the tissue. New analytical methods that allow complex Hg-biomolecules to be analysed intact are needed and only few very recent studies deal with this approach. Therefore, as an initial step towards the characterization of Hg containing biomolecules, an analytical procedure has been optimised using size-exclusion chromatography (SEC) with inductively coupled plasma mass spectrometry (ICP-MS) detection. We applied this technique to elucidate the distribution and elution profile of Hg and Se, and some physiological important elements such as Fe, Ni, Zn and Cu, to assess metal binding profiles in liver and kidney samples of red deer (Cervus elaphus) and wild boar (Sus scrofa) who roam freely within the largest Hg mining district on Earth, Almadén in Spain. Elemental fractionation profiles of the extracts from different tissues were obtained using two different SEC columns (BioSep-SEC-S2000 GL 300-1kDa and Superdex 75 10/300 GL 70-3kDa). Similar profiles of Hg were observed in red deer and wild boar; however, significant differences were evident for liver and kidney. Moreover, the profiles of Se showed a single peak at high-medium molecular weight in all investigated tissues, while co-elution of Hg with Fe, Ni, Zn and Cu was observed.


Assuntos
Exposição Ambiental/análise , Mercúrio/análise , Selênio/análise , Poluentes do Solo/análise , Animais , Cervos , Rim/química , Sus scrofa
9.
Environ Sci Pollut Res Int ; 23(7): 6074-81, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26160125

RESUMO

The impact of mercury (Hg) pollution in the terrestrial environments and the terrestrial food chains including the impact on human food consumption is still greatly under-investigated. In particular, studies including Hg speciation and detoxification strategies in terrestrial animals are almost non-existing, but these are key information with important implications for human beings. Therefore, in this work, we report on Hg species (inorganic mercury, iHg, and monomethylmercury, MeHg) distribution among terrestrial animal tissues obtained from a real-world Hg exposure scenario (Almadén mining district, Spain). Thus, we studied Hg species (iHg and MeHg) and total selenium (Se) content in liver and kidney of red deer (Cervus elaphus; n = 41) and wild boar (Sus scrofa; n = 16). Similar mercury species distribution was found for both red deer and wild boar. Major differences were found between tissues; thus, in kidney, iHg was clearly the predominant species (more than 81%), while in liver, the species distribution was less homogeneous with a percentage of MeHg up to 46% in some cases. Therefore, Hg accumulation and MeHg transfer were evident in terrestrial ecosystems. The interaction between total Se and Hg species has been evaluated by tissue and by animal species. Similar relationships were found in kidney for both Hg species in red deer and wild boar. However, in liver, there were differences between animals. The possible underlying mechanisms are discussed.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/análise , Cadeia Alimentar , Mercúrio/análise , Mineração , Animais , Cervos , Humanos , Selênio/análise , Espanha , Sus scrofa , Suínos
10.
Clin Genet ; 88(6): 579-83, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25512148

RESUMO

Pulmonary arterial hypertension (PAH) is a pathological condition characterized by a persistent and progressive elevation of pulmonary vascular resistance with devastating consequences if untreated. In the past recent years, several genes have been related to PAH, however, the molecular defect remains unknown in a significant proportion of patients with familial PAH (∼20%). During the past few years, we have observed that PAH shows a particular behavior in Iberian Gypsies, with more aggressive course and frequently affecting multiple members of the same family. We studied five Gypsy families in whom at least one individual from each family developed a severe form of PAH and in whom no mutation had been identified in the common genes. We applied SNP-array-based homozygosity mapping in three families and obtained, among others, one of which included the gene EIF2AK4, recently reported in patients with PAH from group-1' pulmonary veno-occlusive disease (PVOD) and pulmonary capillary hemangiomatosis (PCH). Subsequently, we sequenced EIF2AK4 and found a homozygous mutation in all five families: c.3344C>T(p.P1115L). The majority of our patients required early lung transplantation. Hence, this mutation appeared with a more severe phenotype than previously reported for other EIF2AK4 mutations. The finding of this novel mutation is important for genetic counseling and calculation of population recurrence risks.


Assuntos
Hipertensão Pulmonar Primária Familiar/genética , Predisposição Genética para Doença/genética , Mutação , Proteínas Serina-Treonina Quinases/genética , Roma (Grupo Étnico)/genética , Adolescente , Adulto , Sequência de Bases , Hipertensão Pulmonar Primária Familiar/etnologia , Feminino , Efeito Fundador , Predisposição Genética para Doença/etnologia , Homozigoto , Humanos , Masculino , Linhagem , Portugal , Análise de Sequência de DNA , Espanha
11.
Environ Sci Pollut Res Int ; 21(12): 7466-79, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24590602

RESUMO

Mercury is responsible for serious episodes of environmental pollution throughout the world, especially in the Amazon. This toxicity has led regulatory agencies to focus on fish as the target organism for protecting the health of humans and other sensitive organisms. Unfortunately, in the Amazon area, different sampling strategies and the wide variety of sampling areas and fish species make it extremely difficult to determine relationships across geographic regions or over time to ascertain historical trends. Thus, the aim of this work was to achieve three main objectives: a comparative study of mercury contamination in fish of Itaituba (Tapajós, located downstream of the largest gold-mining region in Amazon) and Belém (an area non-exposed to mercury pollution of anthropogenic origin), perform an analysis of inorganic mercury (IHg) versus monomethylmercury (MeHg) contents, and, finally, compare mercury contamination in Tapajós over time. Five piscivorous species were obtained in Itaituba and Belém. Also, four non-piscivorous species were collected in Itaituba. For the first time, mercury speciation showed that (1) current MeHg levels in piscivorous species in Tapajós are higher than those of the non-exposed area, (2) piscivorous species from Itaituba (dourada, filhote, and sarda) contained mercury levels above the World Health Organization safety limit (~17%) and/or above the US Environmental Protection Agency tissue residue criterion (40%), (3) increased MeHg is usually accompanied by increased IHg, and (4) the mean total mercury concentrations for piscivorous species in Itaituba were within the same range and, associated uncertainties as those previously reported, although a remarkable decreasing trend over time was observed for mean total Hg concentrations in non-piscivorous species from Itaituba. The present study supports the importance of continuous monitoring of both populations in the Amazon Rivers. Our results will better assist the development of preventive strategies and governmental actions to confront the problem of mercury contamination in the Amazon.


Assuntos
Peixes/metabolismo , Mercúrio/análise , Rios , Poluentes Químicos da Água/análise , Animais , Brasil , Comércio , Monitoramento Ambiental , Mercúrio/metabolismo , Compostos de Metilmercúrio/análise , Compostos de Metilmercúrio/metabolismo , Poluentes Químicos da Água/metabolismo
12.
Sci Rep ; 3: 1346, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23439489

RESUMO

Multiple osteochondromas is an autosomal dominant skeletal disorder characterized by the formation of multiple cartilage-capped tumours. Two causal genes have been identified, EXT1 and EXT2, which account for 65% and 30% of cases, respectively. We have undertaken a mutation analysis of the EXT1 and EXT2 genes in 39 unrelated Spanish patients, most of them with moderate phenotype, and looked for genotype-phenotype correlations. We found the mutant allele in 37 patients, 29 in EXT1 and 8 in EXT2. Five of the EXT1 mutations were deletions identified by MLPA. Two cases of mosaicism were documented. We detected a lower number of exostoses in patients with missense mutation versus other kinds of mutations. In conclusion, we found a mutation in EXT1 or in EXT2 in 95% of the Spanish patients. Eighteen of the mutations were novel.


Assuntos
Exostose Múltipla Hereditária/genética , Mutação , N-Acetilglucosaminiltransferases/genética , População Branca/genética , Adolescente , Adulto , Criança , Éxons , Estudos de Associação Genética , Humanos , Íntrons , Taxa de Mutação , Linhagem , Espanha , Adulto Jovem
13.
Clin Genet ; 84(6): 566-71, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23347225

RESUMO

Pelizaeus-Merzbacher disease (PMD) is caused in most cases by either duplications or point mutations in the PLP1 gene. This disease, a dysmyelinating disorder affecting mainly the central nervous system, has a wide clinical spectrum and its causing mutations act through different molecular mechanisms. Eighty-eight male patients with leukodystrophy were studied. PLP1 gene analysis was performed by the Multiplex Ligation-dependent Probe Amplification technique and DNA sequencing, and, in duplicated cases of PLP1, gene dosage was completed by using array-CGH. We have identified 21 patients with mutations in the PLP1 gene, including duplications, short and large deletions and several point mutations in our cohort. A customized array-CGH at the Xq22.2 area identified several complex rearrangements within the PLP1 gene region. Mutations found in the PLP1 gene are the cause of PMD in around 20% of the patients in this series.


Assuntos
Mutação , Proteína Proteolipídica de Mielina/genética , Doença de Pelizaeus-Merzbacher/genética , Criança , Pré-Escolar , Hibridização Genômica Comparativa , Genótipo , Humanos , Lactente , Masculino , Doença de Pelizaeus-Merzbacher/diagnóstico , Fenótipo
14.
Talanta ; 99: 859-64, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22967634

RESUMO

No previous analytical procedures are available and validated for mercury speciation analysis in terrestrial animal tissues. This analysis is a difficult task both because the expected concentrations are low, since important accumulation process are not likely to occur, and also because there are not commercially available certified reference material. Thus, an analytical methodology has been developed and validated for mercury speciation for the specific case of terrestrial animal tissues. The proposed method is based on the quantitative extraction of the species by closed-vessel microwave assisted heating with an alkaline reagent, followed by ethylation. The ethylated derivatives were then submitted to head-space solid phase microextraction with a 100 µm polidimethylsiloxane-coated fiber, and desorbed onto a gas chromatograph coupled to atomic fluorescence detection via pyrolysis unit (HS-SPME-GC-pyro-AFS). Procedural detection limits were 31.8 ng g(-1) and 52.5 ng g(-1) for CH(3)Hg(+) and Hg(2+), respectively, for liver and 35.3 ng g(-1) and 58.1 ng g(-1) for CH(3)Hg(+) and Hg(2+), respectively, for kidney. These limits of detection are 5.5 and 6 times better than the obtained without solid phase microextraction for CH(3)Hg(+) and Hg(2+), respectively. The methodology was found linear up to 120 µg L(-1) and reproducible from one day to the following. It was validated with certified reference materials NCS ZC 71001 (beef liver) and BCR No 186 (pig kidney) for total mercury, calculated as the sum of species, and with spiked red deer liver and kidney for speciation. Finally, it was applied to the analysis of samples of red deer liver, red deer kidney and wild boar kidney coming from the Almadén's mercury mining area (Ciudad Real, Spain), the longest and largest producer of mercury in the world until its closure in 2002.


Assuntos
Cervos , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Poluentes Ambientais/química , Mercúrio/análise , Mercúrio/química , Sus scrofa , Absorção , Animais , Boratos/química , Poluentes Ambientais/isolamento & purificação , Hexanos/química , Injeções , Mercúrio/isolamento & purificação , Compostos de Amônio Quaternário/química , Reprodutibilidade dos Testes , Microextração em Fase Sólida , Temperatura , Fatores de Tempo
15.
J Chromatogr A ; 1218(28): 4545-51, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21641604

RESUMO

In this study, we evaluate advantages and disadvantages of three hyphenated techniques for mercury speciation analysis in different sample matrices using gas chromatography (GC) with mass spectrometry (GC-MS), inductively coupled plasma mass spectrometry (GC-ICP-MS) and pyrolysis atomic fluorescence (GC-pyro-AFS) detection. Aqueous ethylation with NaBEt(4) was required in all cases. All systems were validated with respect to precision, with repeatability and reproducibility <5% RSD, confirmed by the Snedecor F-test. All methods proved to be robust according to a Plackett-Burnham design for 7 factors and 15 experiments, and calculations were carried out using the procedures described by Youden and Steiner. In order to evaluate accuracy, certified reference materials (DORM-2 and DOLT-3) were analyzed after closed-vessel microwave extraction with tetramethylammonium hydroxide (TMAH). No statistically significant differences were found to the certified values (p=0.05). The suitability for water samples analysis with different organic matter and chloride contents was evaluated by recovery experiments in synthetic spiked waters. Absolute detection and quantification limits were in the range of 2-6 pg for GC-pyro-AFS, 1-4 pg for GC-MS, with 0.05-0.21 pg for GC-ICP-MS showing the best limits of detection for the three systems employed. However, all systems are sufficiently sensitive for mercury speciation in environmental samples, with GC-MS and GC-ICP-MS offering isotope analysis capabilities for the use of species-specific isotope dilution analysis, and GC-pyro-AFS being the most cost effective alternative.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos de Mercúrio/análise , Animais , Boratos , Cação (Peixe) , Modelos Lineares , Fígado/química , Compostos de Mercúrio/química , Músculos/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Fluorescência , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
16.
Arch Environ Contam Toxicol ; 61(4): 642-52, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21472454

RESUMO

An assessment of mercury (Hg) accumulation in fish from the Tagus River aquatic system (central Spain), which has been influenced by pollution from industrial and urban development, was performed. Total Hg (THg), inorganic Hg (IHg), and monomethylmercury (MMHg) were determined in muscle and liver of different fish species, including Cyprinus carpio, Ameiurus melas, and Chondrostoma miegii, sampled from three locations. Although concentrations of THg and Hg species showed wide variability among the fish species, they were also found to be considerably dependent on location and fish tissue. Relative contents of MMHg to THg in muscle varied from 60 to 88%, whereas those found in liver ranged from 7 to 59%. Mean THg concentrations ranged from 126 to 810 ng/g (dry weight [dw]) in liver and from 159 to 1057 ng/g dw in muscle. Therefore, the mean THg concentration in all fish muscle samples was far lower than the maximum residue level recommended by the European Union for fishery products. Nevertheless, the concentrations of Hg in fish muscle reported in this study were somewhat increased compared with other areas geographically distant from most major anthropogenic Hg sources and, in some cases, even greater than those previously reported elsewhere in more polluted areas. In contrast, Hg contents in liver were lower than those found in Hg-contaminated areas, but they were within the range found in other areas exposed to diffuse sources of pollution by Hg. Thus, this article provides an overview of the concentration and distribution of Hg species in fish muscle and liver tissues samples taken from a freshwater system in the Mediterranean River basin.


Assuntos
Monitoramento Ambiental/métodos , Peixes/metabolismo , Mercúrio/análise , Compostos Organomercúricos/análise , Poluentes Químicos da Água/análise , Animais , Compostos Organomercúricos/classificação , Espanha , Poluentes Químicos da Água/classificação
17.
Anal Sci ; 27(4): 427, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21478620

RESUMO

A new non-aqueous capillary electrophoresis method is proposed for the separation and simultaneous determination of cimetidine, ranitidine, roxatidine, nizatidine and famotidine by using a 30-cm long × 75 µm i.d. fused silica capillary and UV detection at 214 nm. Using a temperature of 25°C, an applied voltage of 15 kV, and a background electrolyte consisting of methanol containing 10 mM ammonium acetate and 0.2% acetic acid allowed the analytes to be separated in less than 4 min. The limits of detection obtained ranged from 7 and 17 µg L(-1). The proposed method was successfully used to determine the analytes in pharmaceutical preparations and its results were checked against an HPLC method.


Assuntos
Eletroforese Capilar/métodos , Antagonistas dos Receptores H2 da Histamina/análise , Antagonistas dos Receptores H2 da Histamina/isolamento & purificação , Antiulcerosos/análise , Antiulcerosos/isolamento & purificação , Reprodutibilidade dos Testes
18.
Environ Int ; 36(6): 593-608, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20483161

RESUMO

This paper presents a review about mercury contamination and human exposure in the Tapajós River basin (Brazil), one of the major tributaries of the Amazon impacted by traditional gold mining from the mid 1980s. The most recent review in this region was published more than ten years ago and since then many articles about environment and especially human populations have revealed new aspects of mercury toxicology. Additionally, new biomarkers of mercury exposure and toxicity have been studied in these populations. However, there are still many open, about both mercury's biogeochemical cycle and mercury health risks. Further environmental and human risk research directions are proposed.


Assuntos
Mercúrio/análise , Rios/química , Poluentes Químicos da Água/análise , Animais , Brasil , Exposição Ambiental/análise , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental , Monitoramento Epidemiológico , Peixes/metabolismo , Sedimentos Geológicos/química , Humanos , Mercúrio/metabolismo , Intoxicação por Mercúrio/epidemiologia , Plantas/metabolismo , Poluentes Químicos da Água/metabolismo
19.
J Laryngol Otol ; 124(6): 599-609, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20307356

RESUMO

BACKGROUND: Exposure to cisplatin leads to cochlear cell death by apoptosis; these changes are most marked on the seventh day after exposure. Heat shock proteins are induced in inner ear cells in response to a variety of stimuli. This study examined the role of heat shock protein 70 in cisplatin-induced cochlear cell death. METHODS: Fifty-six Sprague-Dawley rats were involved. Some were injected with cisplatin (5 mg/kg body weight), some with cisplatin plus the caspase inhibitor Z-Asp(OMe)-Glu(OMe)-Val-Asp(OME)-fluoromethylketone (5 mg/kg body weight) and others were left as controls (being injected only with saline). Seven days later, we examined the expression of heat shock protein 70 and several other apoptosis-related proteins within the rat cochlear cells; we also assessed total superoxide dismutase activity, auditory brainstem response and auditory steady state response. RESULTS: Seven days after cisplatin injection, significantly increased expression of heat shock protein 70 was found within the rat cochleae. This correlated with increased executioner caspase levels, total superoxide dismutase activity and auditory brainstem response thresholds, and a significant elevation in auditory steady state response thresholds. Inhibition of caspase-3 activity significantly reduced cochlear heat shock protein 70 expression and total superoxide dismutase activity, and improved auditory brainstem response and auditory steady state response thresholds. CONCLUSIONS: Seven days after cisplatin exposure, we found disturbances of the cochlear cellular machinery involving heat shock protein 70, other apoptotic proteins and total superoxide dismutase.


Assuntos
Antineoplásicos/toxicidade , Cisplatino/toxicidade , Cóclea/efeitos dos fármacos , Proteínas de Choque Térmico HSP70/metabolismo , Animais , Apoptose/efeitos dos fármacos , Cóclea/metabolismo , Cóclea/patologia , Inibidores de Cisteína Proteinase/farmacologia , Modelos Animais de Doenças , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Injeções Intraperitoneais , Oligopeptídeos/farmacologia , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/efeitos dos fármacos , Superóxido Dismutase/metabolismo
20.
Hum Mutat ; 31(5): E1332-47, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20232352

RESUMO

Blepharophimosis Syndrome (BPES) is an autosomal dominant developmental disorder of the eyelids with or without ovarian dysfunction caused by FOXL2 mutations. Overall, FOXL2deletions represent 12% of all genetic defects in BPES. Here, we have identified and characterized 16 new and one known FOXL2 deletion combining multiplex ligation-dependent probe amplification (MLPA), custom-made quantitative PCR (qPCR) and/or microarray-based copy number screening. The deletion breakpoints could be localized for 13 out of 17 deletions. The deletion size is highly variable (29.8 kb - 11.5 Mb), indicating absence of a recombination hotspot. Although the heterogeneity of their size and breakpoints is not reflected in the uniform BPES phenotype, there is considerable phenotypic variability regarding associated clinical findings including psychomotor retardation (8/17), microcephaly (6/17), and subtle skeletal features (2/17). In addition, in all females in whom ovarian function could be assessed, FOXL2 deletions proved to be associated with variable degrees of ovarian dysfunction. In conclusion, we present the largest series of BPES patients with FOXL2 deletions and standardized phenotyping reported so far. Our genotype-phenotype data can be useful for providing a prognosis (i.e. occurrence of associated features) in newborns with BPES carrying a FOXL2 deletion.


Assuntos
Blefarofimose/genética , Variações do Número de Cópias de DNA/genética , Fatores de Transcrição Forkhead/genética , Deleção de Genes , Mutação/genética , Adolescente , Pré-Escolar , Feminino , Proteína Forkhead Box L2 , Genótipo , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Prognóstico
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