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1.
J Mass Spectrom ; 53(8): 717-724, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29926518

RESUMO

On-surface degradation of sildenafil (an adequate substrate as it contains assorted functional groups in its structure) promoted by the Fenton (Fe2+ /H2 O2 ) and Fenton-like (Mn+ /H2 O2 ; Mn+  = Fe3+ , Co2+ , Cu2+ , Mn2+ ) systems was investigated by using paper spray ionization mass spectrometry (PS-MS). The performance of each system was compared by measuring the ratio between the relative intensities of the ions of m/z 475 (protonated sildenafil) and m/z 235 (protonated lidocaine, used as a convenient internal standard and added to the paper just before the PS-MS analyzes). The results indicated the following order in the rates of such reactions: Fe2+ /H2 O2  â‰« H2 O2  â‰« Cu2+ /H2 O2  > Mn+ /H2 O2 (Mn+  = Fe3+ , Co2+ , Mn2+ ) ~ Mn+ (Mn+  = Fe2+ , Fe3+ , Co2+ , Cu2+ , Mn2 ). The superior capability of Fe2+ /H2 O2 in causing the degradation of sildenafil indicates that Fe2+ efficiently decomposes H2 O2 to yield hydroxyl radicals, quite reactive species that cause the substrate oxidation. The results also indicate that H2 O2 can spontaneously decompose likely to yield hydroxyl radicals, although in a much smaller extension than the Fenton system. This effect, however, is strongly inhibited by the presence of the other cations, ie, Fe3+ , Co2+ , Cu2+ , and Mn2+ . A unique oxidation by-product was detected in the reaction between Fe2+ /H2 O2 with sildenafil, and a possible structure for it was proposed based on the MS/MS data. The on-surface reaction of other substrates (trimethoprim and tamoxifen) with the Fenton system was also investigated. In conclusion, PS-MS shows to be a convenient platform to promptly monitor on-surface oxidation reactions.

2.
Artigo em Português | LILACS | ID: lil-593799

RESUMO

No presente trabalho, foram elaboradas microesferas de acetobutirato de celulose (ABC) contendo cetoprofeno com o objetivo de prolongar a liberação do fármaco. Utilizou-se a técnica de emulsão e evaporação do solvente, variando-se os seguintes parâmetros: massa molar do ABC e a adição ou não de poli(3-hidroxibutirato) (PHB), segundo um planejamento fatorial 22. Maiores eficiências de encapsulação do cetoprofeno foram obtidas quando utilizado ABC com maior massa molar e a adição do PHB levou a uma diminuição do percentual de fármaco encapsulado. Todas as formulações originaram partículas esféricas, com cristais de fármacos aderidos à superfície externa e matriz polimérica porosa quando adicionado o PHB. Os perfis de liberação in vitro indicaram que o aumento da massa molar do ABC levou a uma diminuição do percentual de fármaco inicialmente liberado e a um prolongamento de sua liberação. Por outro lado, a adição do PHB acelerou a liberação do cetoprofeno a partir das microesferas.


In the present study, cellulose acetate butyrate (CAB) microspheres containing ketoprofen were produced, with the objective of prolonging its release. The emulsion/solvent evaporation technique was used to make the spheres, varying the parameters (1) CAB molecular weight and (2) addition or not of poly(3-hydroxybutyrate) [PHB], to optimize drug encapsulation, following a 2² factorial design. Higher ketoprofen encapsulation efficiency was obtained when higher molecular weight CAB was used, while the addition of PHB caused a decrease in the percentage of encapsulated drug. All the preparations produced spherical particles, with drug crystals adhering to the external surface, and a porous polymer matrix when PHB was used. The in vitro release profiles indicated that lowering the CAB molecular weight led to a decrease in the drug initially released and a prolonged release. On the other hand, the addition of PHB accelerated the release of the ketoprofen from the microspheres.


Assuntos
Preparações de Ação Retardada , Cetoprofeno , Microesferas
4.
Am J Clin Nutr ; 34(9): 1925-34, 1981 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6974494

RESUMO

In our survey of the food habits and nutritional status of "Boia-Fria" agricultural migrant workers in Southern Brazil, a special project was undertaken to assess the influence of socioeconomic and dietary deprivation on the physical growth and development and physical performance of their children. Four hundred fifty-five children in Boia-Fria families from Vila Recreio, a periurban slum of Ribeirao Preto located in the interior of the state of Sao Paulo, were examined for body weight, standing height, mid-upper arm muscle circumference, and head circumference. For comparison, 475 children from "Vita et Pax", a private school attended primarily by children of well-to-do families from the city of Ribeirao Preto, were also examined using similar anthropometric procedures. A small group of selected Boia-Fria children and their well-to-do counterparts were subjected to ergometric-cum-electrocardiographic testing for submaximal physical work performance. The overall results of this comparative study indicate that the physical growth and development and the physical performance of the Boia-Fria children are significantly lower than their well-to-do counterparts. It is suggested that the poor anthropometric and ergometric status of the Boia-Fria children is a reflection of poor dietary habits and socioeconomic deprivation prevalent among the agricultural migrant workers and poor periurban populations of Brazil.


Assuntos
Antropometria , Fenômenos Fisiológicos da Nutrição Infantil , Inquéritos Nutricionais , Esforço Físico , Migrantes , Adolescente , Brasil , Criança , Pré-Escolar , Estudos Transversais , Comportamento Alimentar , Feminino , Testes de Função Cardíaca , Humanos , Lactente , Masculino
5.
Am J Clin Nutr ; 33(12): 2669-73, 1980 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7435435

RESUMO

Vitamin E status of agricultural migrant workers representing low socioeconomic population of Southern Brazil was evaluated by determining dietary intake and plasma levels of vitamin E. The mean plasma vitamin E level of 85 female and 39 male subjects was 1.14 +/- 0.33 mg/100 ml or 2.27 +/- 0.53 mg/g of total lipids in plasma. The difference between the plasma vitamin E values of male and female subjects was insignificant. Using various criteria for the assessment of plasma vitamin E levels, it was established that plasma vitamin E expressed in terms of plasma total lipids is a better indicator of vitamin E status. The actual mean alpha-tocopherol intake of this population was 5.51 +/- 3.30 mg/person from a typical diet supplying about 1500 kcal/day. On a 2500 kcl basis, the estimated mean alpha-tocopherol intake would be about 9 mg/day which compares favorably with the intake values reported for well-nourished populations. The main dietary source of vitamin E in this population is the traditional rice and beans diet with increased use of soybean oil and vegetable oil products in recent years. On the whole the vitamin E status of this Brazilian population is quite satisfactory despite inadequacies in their intake of dietary calories and other essential nutrients. The plasma vitamin E status of these subjects supports the dietary data for the intake of vitamin E in this population.


Assuntos
Hiperlipidemias/metabolismo , Migrantes , Vitamina E/metabolismo , Adulto , Agricultura , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Fatores Socioeconômicos , Vitamina E/sangue
6.
Am J Clin Nutr ; 33(3): 702-14, 1980 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7355851

RESUMO

A new class of migrant workers, commonly known as "Boia-Frias", is rapidly growing in the periurban slumbs (favelas) of Brazil. In 1978 a collaborative study was undertaken to assess the food habits and nutritional status of 100 migrant worker families of Vila Recreio, a typical Boia-Fria settlement near Ribeirao Preto in the state of Sao Paulo. The findings of this survey revealed that the traditional diet of Boia-Frias is nutritionally inadequate both in quality and quantity. Their rice and bean-based diet lacks sufficient variety because of the infrequent use of fresh fruits and vegetables, which are available locally, and of supplemental amounts of protein-rich foods of animal origin. Empty-calorie foods such as carbonated drinks and alcoholic beverages are consumed freely; and starchy foods, traditionally used in the North and Northeast of Brazil, are used commonly as weaning foods. Although dietary practices of pregnant and lactating women are poor, breast-feeding is still practiced by most mothers. The biochemical analysis of blood samples did not indicate major subclinical deficiencies except low hematological values and low plasma vitamin A concentrations in about 25% of the population examined. Plasma cholesterol and plasma vitamin E values were found to be normal. However, anthropometric examinations revealed clear signs of malnutrition and/or undernourishment, which likely impairs their capacity for physical work and adversely affects their overall health.


Assuntos
Comportamento Alimentar , Fenômenos Fisiológicos da Nutrição , Migrantes , Adulto , Agricultura , Brasil , Criança , Pré-Escolar , Dieta/normas , Feminino , Nível de Saúde , Humanos , Lactente , Recém-Nascido , Lactação , Masculino , Pessoa de Meia-Idade , Distúrbios Nutricionais , Inquéritos Nutricionais , Gravidez
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