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1.
Food Sci Biotechnol ; 30(8): 1051-1061, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34471559

RESUMO

The aim of this work was to evaluate the technologies effect of cold extraction by centrifugation (CE) and ultrasound-assisted (US-CE) methods without adding water, on the avocado oil yield, nutritional composition, physicochemical characteristics, oxidative stability (oxidation temperature and time, besides activation energy) and accelerated shelf life regarding hexane extraction (control). The US-CE improved the physicochemical properties such as acidity, peroxides, and iodine indexes regarding CE and Control. US-CE improved the yield, nutritional quality of fatty acids, oxidative stability, shelf life, and ω-6/ω-3 ratio regarding CE. Furthermore, US-CE improved the ratio yield/time extraction of the oil and increased the oxidation temperature regarding control. The main advantage of oils extracted using CE and US-CE concerning control was higher oxidative stability. The most representative polyunsaturated fatty acids identified in all treatments were γ-linolenic and conjugated α-linolenic acids. α-linolenic acid was only detected in US-CE and control. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10068-021-00940-w.

2.
J Hazard Mater ; 150(1): 99-108, 2008 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17532119

RESUMO

Apatite and Portland/apatite composite cements containing steelwork dusts have been prepared using a low temperature hydrothermal method (200 degrees C, 48h). The produced solids were characterized by means of XRD, IR, and SEM-EDX, and the remaining liquid was analyzed by ICP. The results clearly show the capability of these cements to inertise the heavy metals contained in steelwork dusts, that is Fe, Pb, Mo, Cr, Mn, Ni, and Zn. In the case of apatitic cements, Fe, Mg, Cr, Mn, and Pb coming from steel dust replaced Ca in the divalent cation position of the apatite structure, while Si and Mo replaced P in tetrahedral position. The average crystal size of the apatite-containing dust is smaller than in pure apatite synthesized using the same procedure, which is related to the magnesium content of the dust, since magnesium seems to inhibit the crystal growth. XRD diagrams of composite cements show only peaks corresponding to phases observed in the single cements, and in that no new phases are found. However, EDX analysis reveals the introduction of cations coming from Portland cement into the apatite structure. From the results of water analysis it could be concluded that the capability of retention is higher in composite matrices than in the pure apatite one. In conclusion, the obtained data allow stating that the proposed method, the hydrothermal synthesis of steelwork dust containing cement, is a reliable one for immobilization of toxic residues containing heavy leachable cations.


Assuntos
Apatitas/química , Metais Pesados/química , Gerenciamento de Resíduos/métodos , Poluentes Químicos da Água/química , Poluição da Água/prevenção & controle , Apatitas/análise , Poeira , Temperatura Alta , Microscopia Eletrônica de Varredura , Aço Inoxidável/química , Poluentes Químicos da Água/análise
3.
J Environ Radioact ; 91(3): 146-59, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17049415

RESUMO

A field study was carried out along the Golfe du Lion, that focussed on the beaches of the Camargue, to locate the main areas where enriched U and Th are found, and to better understand the processes that concentrate radioactivity on beaches. Indeed enriched areas are observed on some Camargue beaches, where high-dose rates are recorded due to excess U and Th activity (>1000 Bq kg(-1)). The coastline was mapped by means of an aerial gamma survey and the results indicated that the main actinides deposits occurred in the Camargue area. This concentrating effect is possibly due to a greater sedimentary contribution from the River Rhone relative to other minor Mediterranean rivers. Across the along-shore profile, the variability in actinides observed at the eastern part of Beauduc spit is mainly explained by variations in heavy and light mineral contents. Such variability can be accounted for by redistribution of the sand caused by erosion/deposition processes occurring in the eastern part of the spit. Further parameters such as grain size and heavy minerals content were studied in connection with the distribution of U, Th and (40)K in the field at a more localised level (i.e. across-shore beach profile). The <200-micro m fraction contains more than 50% of the radioactivity and heavy minerals (especially zircon) are the main contributors to the high levels of external radiation. Therefore the enriched areas, where U and Th exceed 1000 Bq kg(-1), presumably result from the sorting of sand grains according to their size and density.


Assuntos
Radiação de Fundo , Praias , França , Metais Pesados/análise , Óxidos/análise , Dióxido de Silício/química , Poluentes Radioativos do Solo/análise , Tório/análise , Urânio/análise
4.
Talanta ; 45(5): 969-76, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18967086

RESUMO

The simultaneous determination of propranolol and pindolol using synchronous fluorescence spectrometric techniques is described. The method involves measuring the natural fluorescence of these drugs in a 50% (v/v) ethanol-water medium using zero and first derivative synchronous spectrofluorimetry. Under the optimum conditions, the linear determination ranges of propanolol and pindolol are ca. 0.02-1.0 and 0.04-1.2 mug ml(-1), respectively. The results showed that propranolol and pindolol can be determined simultaneously when the concentration ratio of propranolol to pindolol varies from 1:100 to 50:1 in the mixed sample. The method has been satisfactorily applied to the determination of propranolol and pindolol in urine samples and propranolol in pharmaceutical preparations.

5.
Talanta ; 47(3): 537-45, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18967356

RESUMO

Second-derivative synchronous fluorescence spectrometry was used to develop a simple, rapid and sensitive spectrofluorimetric method for the determination of binary mixtures of the nonsteroidal antiinflammatory drugs flufenamic (FFA), meclofenamic (MCFA) and mefenamic (MFA) acids in serum and pharmaceutical formulations. The method is based on the intrinsic fluorescence of these compounds in chloroform. A Deltalambda=105 nm was used for the resolution of FFA-MFA and MFA-MCFA mixtures, whereas the FFA-MCFA mixture was determined at Deltalambda=40 nm. Serum samples are treated with trichloroacetic acid to remove the proteins, and the analytes are extracted in chloroform prior to determination. Pharmaceutical preparations were analysed without prior separation steps.

6.
J Pharm Biomed Anal ; 14(11): 1505-11, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8877856

RESUMO

A reliable and highly sensitive method is described for the determination of chloroxine in pharmaceutical preparations. It involves the formation of a complex between chloroxine and aluminum(III) in a micellar medium. The complex is a very fluorescent species, and there is a linear relationship between chloroxine concentration and fluorescence intensity over the range 2.0 x 10(-8)-5.1 x 10(-5) mol l-1. The limit of detection is 5 x 10(-9) mol l-1. The method can be easily adapted to a flow system using a three-channel manifold, the peak height being proportional to the chloroxine concentration over the range 5.6 x 10(-7)-5.6 x 10(-5) mol l-1. Manual and flow-injection procedures permit the determination of chloroxine in the presence of chlorquinaldol, and have been successfully applied to the determination of chloroxine in pharmaceutical preparations.


Assuntos
Alumínio/química , Amebicidas/análise , Cloroquinolinóis/análise , Clorquinaldol/análise , Fluorometria/métodos , Sensibilidade e Especificidade
7.
J Pharm Biomed Anal ; 17(4-5): 719-24, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9682155

RESUMO

A very simple, rapid and highly sensitive method is described for determining naproxen in serum and urine. This method is based on room temperature phosphorescence of naproxen in sodium dodecylsulphate micelles, with thallium(I) providing the external heavy atom and sodium sulphite acting as the oxygen scavenger. Under the optimum and experimental conditions, the range of application is 0.09-4.5 micrograms ml-1 and the limit of detection is 0.03 micrograms ml-1. The most relevant characteristic of this method is its great selectivity, e.g. naproxen can be determined in the presence of other nonsteroidal anti-inflammatory drugs (NSAIDs). The clinical applicability of this procedure has been tested, analysing naproxen in serum and urine samples. The analytical recoveries and inter- and intra assay precision data obtained demonstrate the usefulness of this procedure when used with very complex samples.


Assuntos
Anti-Inflamatórios não Esteroides/análise , Naproxeno/análise , Análise Espectral/métodos , Anti-Inflamatórios não Esteroides/sangue , Anti-Inflamatórios não Esteroides/urina , Artefatos , Concentração de Íons de Hidrogênio , Medições Luminescentes , Micelas , Naproxeno/sangue , Naproxeno/urina , Oxigênio/química , Sensibilidade e Especificidade , Sulfitos/química , Temperatura
8.
J Radiol ; 67(8-9): 631-5, 1986.
Artigo em Francês | MEDLINE | ID: mdl-3795187

RESUMO

Authors report one case of cerebral ischemic accident by thrombosis of a venous angioma of brain. This kind of malformation is quite unusual and was considered by most authors as unable to involve supratentorial ischemic complications. This case seems to be the first reported in the literature and demonstrates that venous brain ischemic accidents can result from venous angioma of the brain.


Assuntos
Isquemia Encefálica/etiologia , Neoplasias Encefálicas/complicações , Hemangioma/complicações , Adulto , Isquemia Encefálica/diagnóstico por imagem , Neoplasias Encefálicas/diagnóstico por imagem , Angiografia Cerebral , Veias Cerebrais/diagnóstico por imagem , Feminino , Hemangioma/diagnóstico por imagem , Humanos , Tomografia Computadorizada por Raios X
9.
Neurochirurgie ; 31(3): 161-8, 1985.
Artigo em Francês | MEDLINE | ID: mdl-4033855

RESUMO

Clinical, computed tomography and angiography investigations were conducted in 15 cases of venous angioma of brain. These rare malformations (70 cases reported) are often asymptomatic or are revealed by the onset of epileptic seizures. The scanner produced images suggestive of a vascular malformation in 80% of cases. However, the purely venous character of the angioma and its exact site require confirmation supplied by angiography only, the lesion provoking characteristic images from the latter examination.


Assuntos
Angiografia Cerebral , Hemangioma/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Encéfalo/patologia , Dilatação Patológica , Feminino , Humanos , Masculino , Bulbo/irrigação sanguínea , Pessoa de Meia-Idade , Veias/anormalidades
10.
Meat Sci ; 90(1): 106-15, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21703779

RESUMO

The present study investigates the effects of avocado, sunflower and olive oils used as back-fat replacers, on the fatty acid composition, oxidative stability, volatiles profile and color and texture properties of cooked pork patties. The vegetable oils modified the fatty acid profiles of the patties by lowering the percentages of SFA (from 36.96% to ~25.30%) and reducing the atherogenic index (from 0.41 to ~0.24). Vegetable oils had higher amounts of antioxidant compounds such as tocopherols (10.8-53.9 mg/100 g) than back-fat (5.9 mg/100 g). Consistently, patties manufactured with the oils had significantly lower amounts of lipid and protein oxidation products than control patties. Avocado oil contributed with specific aroma-active terpenes to patties and had a significant impact on particular color and texture parameters. The results from this study highlight the technological applications of the vegetable oils as food ingredients in the design of healthier meat commodities.


Assuntos
Lipídeo A/química , Produtos da Carne/análise , Produtos da Carne/normas , Persea/química , Óleos de Plantas/química , Animais , Bovinos , Azeite de Oliva , Oxirredução , Análise de Componente Principal , Óleo de Girassol , Suínos
11.
Meat Sci ; 89(2): 166-73, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21555188

RESUMO

Processing of avocados generates an important amount of by-products such as peels and seeds that are rich in bioactive substances with proven radical suppressing activities. The objective of this study was to evaluate the effectiveness of peel and seed extracts from two avocado varieties-'Hass' and 'Fuerte'-as inhibitors of lipid and protein oxidation and color deterioration of raw porcine patties during chilled storage (4 °C/15 days). Avocado extracts significantly (p<0.05) reduced the loss of redness and the increase of lightness during storage of porcine patties. 'Fuerte' extracts were more efficient at inhibiting discoloration of chilled patties than 'Hass' extracts. Patties treated with avocado extracts had significantly lower amounts of TBA-RS than control ones throughout the storage. 'Hass' avocado extracts significantly inhibited the formation of protein carbonyls in chilled patties at day 15. The present results highlight the potential usage of extracts from avocado by-products as ingredients for the production of muscle foods with enhanced quality traits.


Assuntos
Antioxidantes/farmacologia , Produtos da Carne , Persea/química , Extratos Vegetais/farmacologia , Animais , Temperatura Baixa , Cor , Culinária , Manipulação de Alimentos/métodos , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Frutas/química , Peroxidação de Lipídeos/efeitos dos fármacos , Carbonilação Proteica/efeitos dos fármacos , Refrigeração , Sementes/química , Suínos
12.
J Food Sci ; 76(7): C1025-31, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22417539

RESUMO

UNLABELLED: The present study was aimed to examine the impact of partial back-fat replacement (50%) by avocado (A), sunflower (S), and olive (O) oil on the chemical composition, oxidative stability, color, and texture of porcine burger patties (10% fat) subjected to oven cooking (170 °C/18 min) and chilling (+ 4 °C/15 d). The addition of vegetable oils caused a significant reduction of saturated fatty acids and a concomitant enrichment in unsaturated fatty acids. The incorporation of vegetable oils to porcine patties caused a significant reduction of TBARS formed as a result of cooking and the subsequent chilling. The usage of vegetable oils as back-fat replacers had no impact on the formation of protein carbonyls. Porcine patties with A- and O-patties displayed a more favorable ratio between volatiles contributing to rancidity and those contributing pleasant odor notes. Treated and control patties underwent similar discoloration during processing. The usage of vegetable oils and particularly, avocado and olive oils, as back-fat replacers, could be an interesting strategy to improve the nutritional and technological properties of porcine patties. PRACTICAL APPLICATION: The present study highlights the potential nutritional and technological benefits of replacing animal fat by vegetable oils in porcine patties subjected to cooking and chilling. The industrial application of vegetable oils in processed meat products would meet the current consumers' interest towards healthier food products. In addition, the usage of avocado oil would contribute to boost the avocado industry by providing an additional value to a by-product of great biological significance.


Assuntos
Gorduras na Dieta/análise , Conservação de Alimentos/métodos , Temperatura Alta , Carne/análise , Óleos de Plantas , Suínos , Animais , Temperatura Baixa , Cor , Ácidos Graxos/análise , Azeite de Oliva , Oxirredução , Persea/química , Sensação , Óleo de Girassol , Substâncias Reativas com Ácido Tiobarbitúrico/análise
15.
Analyst ; 117(6): 1025-8, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1503229

RESUMO

A flow injection configuration is proposed for the determination of L-cysteine and L-cystine individually and for mixtures of both analytes. The procedure is based on the rapid oxidation of L-cysteine by thallium(III) with concomitant formation of fluorescent thallium(I). The inclusion of a selecting valve and of a copper-coated cadmium column in the configuration allows the successive determination of two analytes. Linear calibration graphs were obtained between 5 x 10(-6) and 5 x 10(-5) mol dm-3 of L-cysteine and between 2 x 10(-6) and 2 x 10(-5) mol dm-3 of L-cystine. The applicability of the method to the determination of L-cysteine and L-cystine in pharmaceutical preparations was demonstrated by investigating the effect of potential interferents and by the analysis of commercial preparations. The method was successfully applied to the determination of L-cysteine and L-cystine in urine samples.


Assuntos
Cisteína/urina , Cistinúria/urina , Análise de Injeção de Fluxo , Humanos , Indicadores e Reagentes , Espectrometria de Fluorescência
16.
Analyst ; 122(7): 705-8, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9330040

RESUMO

Simple, rapid, accurate and sensitive spectrofluorimetric methods for the determination of norfloxacin are described. The methods are based on the reaction of this drug with aluminium(III) ion to form a strongly fluorescent complex. Fluorescence properties of the AlIII-norfloxacin complex were used for the determination of this drug in pharmaceutical preparations. First-derivative constant wavelength synchronous fluorescence spectrometry was used for the determination of norfloxacin in the presence of nalidixic acid. The determination of norfloxacin in urine without the need of tedious pre-separation was achieved by using zero-crossing second-derivative synchronous fluorescence spectrometry.


Assuntos
Anti-Infecciosos/análise , Norfloxacino/análise , Preparações Farmacêuticas/química , Alumínio , Anti-Infecciosos/urina , Humanos , Masculino , Norfloxacino/urina , Espectrometria de Fluorescência
17.
Neuroradiology ; 26(1): 45-9, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6738842

RESUMO

Extracranial vertebral arteriovenous fistulae of non traumatic origin are extremely rare. The authors report two cases of spontaneous vertebro-vertebral arteriovenous fistulae associated with fibromuscular dysplasia. They discuss the relation-ship between arteriovenous fistulae and fibro-muscular dysplasia, and the specific problems of treatment in these two cases.


Assuntos
Arteriopatias Oclusivas/complicações , Fístula Arteriovenosa/etiologia , Displasia Fibromuscular/complicações , Artéria Vertebral , Idoso , Angiografia , Fístula Arteriovenosa/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade
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