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1.
Sensors (Basel) ; 23(3)2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36772353

RESUMO

TiO2 and CeO2 are well known as oxygen sensing materials. Despite high sensitivity, the actual utilization of these materials in gas detection remains limited. Research conducted over the last two decades has revealed synergistic effects of TiO2-CeO2 mixed oxides that have the potential to improve some aspects of oxygen monitoring. However, there are no studies on the sensing properties of the TiO2-CeO2 obtained by mechanochemical treatment. We have tested the applicability of the mechanochemically treated TiO2-CeO2 for oxygen detection and presented the results in this study. The sensing layers are prepared as a porous structure by screen printing a thick film on a commercial substrate. The obtained structures were exposed to various O2 concentrations. The results of electrical measurements showed that TiO2-CeO2 films have a significantly lower resistance than pure oxide films. Mixtures of composition TiO2:CeO2 = 0.8:0.2, ground for 100 min, have the lowest electrical resistance among the tested materials. Mixtures of composition TiO2:CeO2 = 0.5:0.5 and ground for 100 min proved to be the most sensitive. The operating temperature can be as low as 320 °C, which places this sensor in the class of semiconductor sensors working at relatively lower temperatures.

2.
Br J Nutr ; 127(8): 1224-1231, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-34103111

RESUMO

Despite evidence showing that the intake of ultra-processed food has a negative impact on health, diet quality and dietary vitamin E, its impact on vitamin E nutritional status and breast milk remains unknown. This study aimed to assess the influence of the consumption of ultra-processed foods on vitamin E biomarkers of lactating women. A cross-sectional study was performed with 294 lactating women. Food consumption was obtained by 24-h dietary recall, and foods were grouped according to the NOVA classification. Levels of α-tocopherol were analysed by HPLC. Breast milk vitamin E (BMVE) adequacy was based on the quantity of the vitamin in the estimated intake volume. The Kruskal­Wallis test was used to compare the tertiles and linear regression to association between ultra-processed food consumption and biomarkers. Ultra-processed foods accounted for 16 % of energy intake and vitamin E intakes by all women were considered low. Serum α-tocopherol was 26·55 (sd 7·98) µmol/l, 5 % (n 11) showed inadequate vitamin E (< 12 µmol/l) and 78 % had an inadequate BMVE content (< 4 mg/780 ml). The regression showed that a higher dietary share of ultra-processed foods was associated with lower concentrations of serum α-tocopherol (ß = ­0·168, 95 % CI ­0·047, 0·010, P = 0·003) and inadequate BMVE content (ß = ­0·144, 95 % CI = ­0·505, 0·063, P = 0·012) (adjustment for income and maternal age). Thus, higher dietary shares of ultra-processed foods had an impact on vitamin E biomarkers, suggesting that inadequate dietary intake practices during lactation may reduce the supply of vitamin E to women and breast milk.


Assuntos
Lactação , Vitamina E , Biomarcadores , Brasil , Estudos Transversais , Dieta , Fast Foods , Feminino , Humanos
3.
J Pediatr Gastroenterol Nutr ; 70(6): 858-863, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32443047

RESUMO

OBJECTIVE: Dietary lipid intake is associated with serum alpha-tocopherol levels; however, its impact on human milk is unknown. The objective of this study was to evaluate the relationship between maternal intake of vitamin E, lipids, and fatty acids and the concentration of alpha-tocopherol in human milk. METHODS: We conducted a longitudinal observational study, including 143 lactating women on 7, 30, and 90 days postpartum. Dietary intake was collected using 24-hour recall. On day 90, a human milk sample was collected and analyzed for alpha-tocopherol concentration. The prevalence of inadequate vitamin E intake was determined by the Estimated Average Requirement (16 mg/day), and the alpha-tocopherol concentration was analyzed by high-performance liquid chromatography. RESULTS: Dietary intake of vitamin E was associated with the intake of lipids (r = 0.237, P = 0.004) and fatty acids (P < 0.05), and 100% of the participants had inadequate vitamin intake. Mean alpha-tocopherol concentration in the human milk samples was 7.11 (standard deviation 3.95) µmol/L and was correlated with lipid (r = 0.201, P = 0.042) and polyunsaturated fatty acid intake (r = 0.235, P = 0.017). Higher vitamin E levels were found in participants with the highest quartile of polyunsaturated fatty acid intake. CONCLUSIONS: Alpha-tocopherol concentration was associated with the dietary intake of lipids and fatty acids, demonstrating that its bioavailability is associated with fats in the mammary gland. These results suggest development of appropriate strategies to increase the levels of vitamin E in breast milk that may help to prevent and treat vitamin E deficiency.


Assuntos
Leite Humano , alfa-Tocoferol , Feminino , Humanos , Lactação , Leite Humano/química , Estado Nutricional , Vitamina E
4.
Planta Med ; 77(4): 383-7, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20922653

RESUMO

Two new aporphinoid alkaloids, (+)-6 S-ocoteine N-oxide and (+)-norocoxylonine, were isolated from the leaves and trunk bark of OCOTEA ACUTIFOLIA (Lauraceae) along with thirteen aporphine analogues, one morphinan alkaloid, and one flavonoid. The aporphine alkaloids (+)-thalicsimidine and (+)-neolitsine are reported for the first time for the genus OCOTEA. The structures of all compounds were established on the basis of 1D- and 2D-NMR spectroscopic techniques, optical rotation and/or mass spectrometry data. The cytotoxic potential of eight of the aporphine alkaloids against four human cancer cell lines (Hep-2, MCF-7, B16-F10 and 786-0) was also evaluated.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Aporfinas/farmacologia , Neoplasias/tratamento farmacológico , Ocotea/química , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/uso terapêutico , Aporfinas/química , Aporfinas/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Fitoterapia , Casca de Planta , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Folhas de Planta
5.
J Appl Physiol (1985) ; 112(5): 911-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22194320

RESUMO

Environmentally relevant doses of inhaled diesel particles elicit pulmonary inflammation and impair lung mechanics. Eugenol, a methoxyphenol component of clove oil, presents in vitro and in vivo anti-inflammatory and antioxidant properties. Our aim was to examine a possible protective role of eugenol against lung injuries induced by diesel particles. Male BALB/c mice were divided into four groups. Mice received saline (10 µl in; CTRL group) or 15 µg of diesel particles DEP (15 µg in; DIE and DEUG groups). After 1 h, mice received saline (10 µl; CTRL and DIE groups) or eugenol (164 mg/kg; EUG and DEUG group) by gavage. Twenty-four hours after gavage, pulmonary resistive (ΔP1), viscoelastic (ΔP2) and total (ΔPtot) pressures, static elastance (Est), and viscoelastic component of elastance (ΔE) were measured. We also determined the fraction areas of normal and collapsed alveoli, amounts of polymorpho- (PMN) and mononuclear cells in lung parenchyma, apoptosis, and oxidative stress. Est, ΔP2, ΔPtot, and ΔE were significantly higher in the DIE than in the other groups. DIE also showed significantly more PMN, airspace collapse, and apoptosis than the other groups. However, no beneficial effect on lipid peroxidation was observed in DEUG group. In conclusion, eugenol avoided changes in lung mechanics, pulmonary inflammation, and alveolar collapse elicited by diesel particles. It attenuated the activation signal of caspase-3 by DEP, but apoptosis evaluated by TUNEL was avoided. Finally, it could not avoid oxidative stress as indicated by malondialdehyde.


Assuntos
Eugenol/farmacologia , Pulmão/efeitos dos fármacos , Pneumonia/induzido quimicamente , Pneumonia/tratamento farmacológico , Alvéolos Pulmonares/efeitos dos fármacos , Emissões de Veículos/toxicidade , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Marcação In Situ das Extremidades Cortadas/métodos , Peroxidação de Lipídeos/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Pneumonia/metabolismo , Pneumonia/patologia , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/patologia , Mecânica Respiratória/efeitos dos fármacos
6.
Rev. bras. farmacogn ; 22(5): 1018-1023, Sept.-Oct. 2012. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-649655

RESUMO

The Piper species chemistry has been widely investigated and the phytochemical analyses have led to the isolation of a number of active compounds like alkaloids, terpenes and flavones among others. The aim of this study was to evaluate the leishmanicidal activity of 2-[1-hydroxy-3-phenyl-(Z,2E)-2-propenylidene]-4-methyl-4-cyclopentene-1,3-dione (DCPC), a cyclopentenedione derivative isolated from the roots of Piper carniconnectivum C. DC., Piperaceae. Leishmanicidal activity against Leishmania amazonensis promastigotes was assessed, and the risk to host cell was assessed by measuring the cytotoxicity to peritoneal macrophages from BALB/c mice in vitro. L. amazonensis promastigotes and host macrophages were cultured in the presence of 100, 50, 25, 12.5 and 6 µg/mL of the cyclopentenedione derivative for up to 96 h. At the end of this period, the inhibitory concentrations (IC50) were compared with those from untreated cultures. The IC50 for promastigotes was 4.4 µg/mL after 96 h of treatment with the derivative. The 50% cytotoxic concentration (CC50) against murine peritoneal macrophages was 129 µg/mL. These results indicate that DCPC is a promising molecule for the development of leishmanicidal drugs.

7.
Rev. Inst. Med. Trop. Säo Paulo ; 38(1): 45-53, jan.-fev. 1996. ilus, tab
Artigo em Inglês | LILACS | ID: lil-172651

RESUMO

A colonizacao do colo e reto por espiroquetas intestinais foi detectada pela primeira vez no Brasil em 4 de 282 (1,41 por cento) pacientes submetidos a sigmoidoscopia e/ou colonoscopia com o diagnostico histopatologico de colite cronica inespecifica. A frequencia e provavelmente menor que a real, uma vez que especimens cirurgicos nao foram considerados no presente estudo. O diagnostico histopatologico foi feito atraves de coloracoes de rotina, tais como a hematoxilina-eosina, que mostraram franja basofilica de 3u de espessura sobre a borda em escova do epitelio e por impregnacoes pela prata como o metodo de Whartin-Starry. Metodos imunohistoquimicos, usando dois soros primarios policlonais, um contra o Treponema pallidum e outro contra Leptospira interrogans, serovar copenhageni serogrupo...


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Colite/etiologia , Infecções por Spirochaetales/diagnóstico , Intestinos/parasitologia , Imuno-Histoquímica , Spirochaetales/crescimento & desenvolvimento
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