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1.
Br J Nutr ; 131(11): 1827-1840, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38410884

RESUMO

The purpose of this study was to investigate the effect of an egg white hydrolysate (EWH) to protect white adipose tissue damage from cardiometabolic changes induced by severe hypertension. Male Wistar rats were uninephrectomised and divided: SHAM (weekly subcutaneous vehicle (mineral oil + propylene glycol, 1:1)), SHAM + EWH (subcutaneous vehicle plus EWH via gavage, 1 g/kg per day), DOCA (deoxycorticosterone acetate diluted in vehicle subcutaneously weekly in subsequent doses of 20 mg/kg -1st week, 12 mg/kg - 2­3th week, and 6 mg/kg -4­8th week, respectively, plus 1 % NaCl and 0·2 % KCl in drinking water), and DOCA + EWH. Body weight gain, food and water intake, glucose and lipid metabolism were evaluated. Oxidative stress was assessed by biochemical assay and immunofluorescence for NOX-1, nuclear factor kappa B (NFκB), and caspase-3 in retroperitoneal white adipose tissue (rtWAT). Proinflammatory cytokines (IL-6 and 1ß), CD163+ macrophage infiltration, and immunohistochemistry for TNFα and uncoupling protein-1 were evaluated, as well as histological analysis on rtWAT. Glutathione peroxidase and reductase were also determined in plasma. EWH showed hypocholesterolemic, antioxidant, anti-inflammatory, and anti-apoptotic properties in the arterial hypertension DOCA-salt model. The results demonstrated the presence of functional changes in adipose tissue function by a decrease in macrophage infiltration and in the fluorescence intensity of NFκB, NOX-1, and caspase-3. A reduction of proinflammatory cytokines and restoration of antioxidant enzymatic activity and mitochondrial oxidative damage by reducing uncoupling protein-1 fluorescence intensity were also observed. EWH could be used as a potential alternative therapeutic strategy in the treatment of cardiometabolic complications associated with malignant secondary arterial hypertension.


Assuntos
Tecido Adiposo Branco , Acetato de Desoxicorticosterona , Clara de Ovo , Estresse Oxidativo , Ratos Wistar , Animais , Masculino , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Clara de Ovo/química , Ratos , Hipertensão/metabolismo , Hipertensão/induzido quimicamente , Hidrolisados de Proteína/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Proteína Desacopladora 1/metabolismo , Gordura Intra-Abdominal/metabolismo , Gordura Intra-Abdominal/efeitos dos fármacos
2.
Foods ; 12(11)2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37297415

RESUMO

In commercial terms, Extra Virgin Olive Oil (EVOO) is considered an exceptional food with excellent sensory and nutritional quality due to its taste, odor, and bioactive compounds; as such, it is of great health interest. This quality can be affected by the oxidative degradation, both chemical and enzymatic (the activity of oxidative, endogenous enzymes from the polyphenol oxidase and peroxidase olive fruit type), of essential components during the extraction and conservation of EVOO. In the bibliography, oxygen reduction during the malaxation process and oil storage has been studied in different ways. However, research concerning oxygen reduction in the crushing of the olive fruit or the malaxation of the paste, or both, in the "real extraction condition" is scarce. Oxygen reduction has been compared to control conditions (the concentration of atmospheric oxygen (21%)). Batches of 200 kg of the olive fruit, 'Picual' cultivar, were used and the following treatments were applied: Control (21% O2 Mill-21% O2 Mixer), "IC-NM": Inerted crushing -Normal malaxation (6.25% O2 Mill-21% O2 Mixer), "NC-IM": Normal crushing-Inerted malaxation (21% O2 Mill-4.39% O2 Mixer) and "IC-IM": Inerted crushing -Inerted malaxation (5.5% O2 Mill-10.5% O2 Mixer). The parameters of commercial quality covered by regulation (free acidity, peroxide value and absorbency in ultra-violet (K232 and K270)) did not suffer any change concerning the control, and so the oils belong to the commercial category of "Extra Virgin Olive Oil". The phenolic compounds of the olives involved in the distinctive bitter and pungent taste, health properties, and oxidative stability are increased with the downsizing amounts of oxygen in the IC-NM, NC-IM, and IC-IM treatments with an average of 4, 10, and 20%, respectively. In contrast, the total amount of volatile compounds decreases by 10-20% in all oxygen reduction treatments. The volatile compounds arising from the lipoxygenase pathway, which are responsible for the green and fruity notes of EVOO, also decreased in concentration with the treatments by 15-20%. The results show how oxygen reduction in the milling and malaxation stages of olive fruit can modulate the content of phenols, volatile compounds, carotenoids, and chlorophyll pigments in the EVOO to avoid the degradation of the compound with sensorial and nutritional interest.

3.
Sci Rep ; 9(1): 1868, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30755648

RESUMO

Aluminum (Al), which is omnipresent in human life, is a potent neurotoxin. Here, we have tested the potential for Egg White Hydrolysate (EWH) to protect against changes in cognitive function in rats exposed to both high and low levels of Al. Indeed, EWH has been previously shown to improve the negative effects induced by chronic exposure to heavy metals. Male Wistar rats received orally: Group 1) Low aluminum level (AlCl3 at a dose of 8.3 mg/kg b.w. during 60 days) with or without EWH treatment (1 g/kg/day); Group 2) High aluminum level (AlCl3 at a dose of 100 mg/kg b.w. during 42 days) with or without EWH treatment (1 g/kg/day). After 60 or 42 days of exposure, rats exposed to Al and EWH did not show memory or cognitive dysfunction as was observed in Al-treated animals. Indeed, co-treatment with EWH prevented catalepsy, hippocampal oxidative stress, cholinergic dysfunction and increased number of activated microglia and COX-2-positive cells induced by Al exposure. Altogether, since hippocampal inflammation and oxidative damage were partially prevented by EWH, our results suggest that it could be used as a protective agent against the detrimental effects of long term exposure to Al.


Assuntos
Alumínio/toxicidade , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/prevenção & controle , Clara de Ovo , Alimento Funcional , Hidrolisados de Proteína/uso terapêutico , Acetilcolinesterase/metabolismo , Animais , Antioxidantes/metabolismo , Comportamento Animal , Peso Corporal , Ciclo-Oxigenase 2/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Memória de Longo Prazo/efeitos dos fármacos , Memória de Curto Prazo/efeitos dos fármacos , Microglia/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Estresse Oxidativo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
4.
Phys Chem Chem Phys ; 20(34): 22076-22083, 2018 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-30112549

RESUMO

In the last ten years, there has been an acceleration in the pace at which new catalysts for the water-gas shift reaction are designed and synthesized. Pt-based catalysts remain the best solution when only activity is considered. However, cost, operation temperature, and deactivation phenomena are important variables when these catalysts are scaled in industry. Here, a new catalyst, Au/TiO2-Y2O3, is presented as an alternative to the less selective Pt/oxide systems. Experimental and theoretical techniques are combined to design, synthesize, characterize and analyze the performance of this system. The mixed oxide demonstrates a synergistic effect, improving the activity of the catalyst not only at large-to-medium temperatures but also at low temperatures. This effect is related to the homogeneous dispersion of the vacancies that act both as nucleation centers for smaller and more active gold nanoparticles and as dissociation sites for water molecules. The calculated reaction path points to carboxyl formation as the rate-limiting step with an activation energy of 6.9 kcal mol-1, which is in quantitative agreement with experimental measurements and, to the best of our knowledge, it is the lowest activation energy reported for the water-gas shift reaction. This discovery demonstrates the importance of combining experimental and theoretical techniques to model and understand catalytic processes and opens the door to new improvements to reduce the operating temperature and the deactivation of the catalyst.

5.
J Integr Plant Biol ; 58(1): 48-66, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25869057

RESUMO

Elucidating the relationships between gene expression and the physiological mechanisms remains a bottleneck in breeding for resistance to salinity and drought. This study related the expression of key target genes with the physiological performance of durum wheat under different combinations of salinity and irrigation. The candidate genes assayed included two encoding for the DREB (dehydration responsive element binding) transcription factors TaDREB1A and TaDREB2B, another two for the cytosolic and plastidic glutamine synthetase (TaGS1 and TaGS2), and one for the specific Na(+) /H(+) vacuolar antiporter (TaNHX1). Expression of these genes was related to growth and different trait indicators of nitrogen metabolism (nitrogen content, stable nitrogen isotope composition, and glutamine synthetase and nitrate reductase activities), photosynthetic carbon metabolism (stable carbon isotope composition and different gas exchange traits) and ion accumulation. Significant interaction between genotype and growing conditions occurred for growth, nitrogen content, and the expression of most genes. In general terms, higher expression of TaGS1, TaGS2, TaDREB2B, and to a lesser extent of TaNHX1 were associated with a better genotypic performance in growth, nitrogen, and carbon photosynthetic metabolism under salinity and water stress. However, TaDREB1A was increased in expression under stress compared with control conditions, with tolerant genotypes exhibiting lower expression than susceptible ones.


Assuntos
Regulação da Expressão Gênica de Plantas , Salinidade , Triticum/genética , Triticum/fisiologia , Adaptação Fisiológica/genética , Biomassa , Carbono/metabolismo , Citosol/metabolismo , Desidratação , Gases/metabolismo , Genes de Plantas , Genótipo , Íons , Nitrogênio/metabolismo , Peptídeos/metabolismo , Fotossíntese/genética , Transpiração Vegetal/genética , Característica Quantitativa Herdável , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Estresse Fisiológico , Triticum/crescimento & desenvolvimento
6.
PLoS One ; 10(6): e0130438, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26091523

RESUMO

It is well established that the plastidic isoform of glutamine synthetase (GS2) is the enzyme in charge of photorespiratory ammonium reassimilation in plants. The metabolic events associated to photorespiratory NH4(+) accumulation were analyzed in a Lotus japonicus photorespiratory mutant lacking GS2. The mutant plants accumulated high levels of NH4(+) when photorespiration was active, followed by a sudden drop in the levels of this compound. In this paper it was examined the possible existence of enzymatic pathways alternative to GS2 that could account for this decline in the photorespiratory ammonium. Induction of genes encoding for cytosolic glutamine synthetase (GS1), glutamate dehydrogenase (GDH) and asparagine synthetase (ASN) was observed in the mutant in correspondence with the diminishment of NH4(+). Measurements of gene expression, polypeptide levels, enzyme activity and metabolite levels were carried out in leaf samples from WT and mutant plants after different periods of time under active photorespiratory conditions. In the case of asparagine synthetase it was not possible to determine enzyme activity and polypeptide content; however, an increased asparagine content in parallel with the induction of ASN gene expression was detected in the mutant plants. This increase in asparagine levels took place concomitantly with an increase in glutamine due to the induction of cytosolic GS1 in the mutant, thus revealing a major role of cytosolic GS1 in the reassimilation and detoxification of photorespiratory NH4(+) when the plastidic GS2 isoform is lacking. Moreover, a diminishment in glutamate levels was observed, that may be explained by the induction of NAD(H)-dependent GDH activity.


Assuntos
Compostos de Amônio/metabolismo , Glutamato-Amônia Ligase/genética , Lotus/enzimologia , Aspartato-Amônia Ligase/metabolismo , Glutamato Desidrogenase/metabolismo , Glutamato-Amônia Ligase/deficiência , Glutamato-Amônia Ligase/metabolismo , Lotus/genética , Lotus/metabolismo , Mutação , Fotossíntese , Folhas de Planta/enzimologia , Folhas de Planta/metabolismo , Plastídeos/enzimologia , Plastídeos/genética , Plastídeos/metabolismo , RNA de Plantas/isolamento & purificação , RNA de Plantas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
7.
J Infect Dev Ctries ; 8(1): 1-4, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24423706

RESUMO

Malaria still poses a real threat to travellers, particularly in areas with high transmission rates such as sub-Saharan Africa, Papua New Guinea, and the South Pacific islands. Malaria causes an estimated 660,000 deaths each year from 219 million cases of illness. It is a preventable and curable disease. Malaria symptoms appear after a period of seven days or longer, and without treatment, the disease can lead to death. Mosquito bite prevention is the main way to reduce malaria transmission. Chemoprophylaxis recommendations depend on travelers' age, destination, type of travelling, or length of stay. Pregnant women, children, and immunosuppressed travelers are the most susceptible. There are currently no licensed vaccines against malaria. Results about a research vaccine candidate known as RTS,S/AS01 are expected in 2015.


Assuntos
Malária/epidemiologia , Malária/prevenção & controle , África Subsaariana/epidemiologia , Quimioprevenção/métodos , Países em Desenvolvimento , Humanos , Controle de Mosquitos/métodos , Ilhas do Pacífico/epidemiologia , Papua Nova Guiné/epidemiologia
8.
Mol Plant Microbe Interact ; 25(2): 211-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22007601

RESUMO

Two photorespiratory mutants of Lotus japonicus deficient in plastid glutamine synthetase (GS(2)) were examined for their capacity to establish symbiotic association with Mesorhizobium loti bacteria. Biosynthetic glutamine synthetase (GS) activity was reduced by around 40% in crude nodule extracts from mutant plants as compared with the wild type (WT). Western blot analysis further confirmed the lack of GS(2) polypeptide in mutant nodules. The decrease in GS activity affected the nodular carbon metabolism under high CO(2) (suppressed photorespiration) conditions, although mutant plants were able to form nodules and fix atmospheric nitrogen. However, when WT and mutant plants were transferred to an ordinary air atmosphere (photorespiratory active conditions) the nodulation process and nitrogen fixation were substantially affected, particularly in mutant plants. The number and fresh weight of mutant nodules as well as acetylene reduction activity showed a strong inhibition compared with WT plants. Optical microscopy studies from mutant plant nodules revealed the anticipated senescence phenotype linked to an important reduction in starch and sucrose levels. These results show that, in Lotus japonicus, photorespiration and, particularly, GS(2) deficiency result in profound limitations in carbon metabolism that affect the nodulation process and nitrogen fixation.


Assuntos
Glutamato-Amônia Ligase/metabolismo , Lotus/enzimologia , Mesorhizobium/fisiologia , Plastídeos/enzimologia , Nódulos Radiculares de Plantas/enzimologia , Carboidratos/análise , Carbono/metabolismo , Respiração Celular , Regulação da Expressão Gênica de Plantas/fisiologia , Glutamato-Amônia Ligase/genética , Isoenzimas , Lotus/genética , Lotus/microbiologia , Lotus/ultraestrutura , Mutação , Nitrogênio/metabolismo , Fixação de Nitrogênio/fisiologia , Fenótipo , Nódulos Radiculares de Plantas/genética , Nódulos Radiculares de Plantas/microbiologia , Nódulos Radiculares de Plantas/ultraestrutura , Simbiose
9.
Planta ; 231(5): 1101-11, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20237895

RESUMO

We have studied the possible role, in a plant glutamine synthetase (GS), of the different cysteinyl residues present in this enzyme. For this purpose we carried out the site-directed mutagenesis of the cDNA for alpha-GS polypeptide from Phaseolus vulgaris in the positions corresponding to Cys-92, Cys-159, and Cys-179, followed by heterologous expression in E. coli and enzymatic characterisation of WT and mutant proteins. The results show that neither Cys-92 nor Cys-179 residues were essential for enzyme activity, but the replacement of Cys-159 by alanine or serine strongly affects the quaternary structure and function of the GS enzyme molecule, resulting in a complete loss of enzymatic activity. Other studies using sulfhydryl specific reagents such as pHMB (p-hydroxymercuribenzoate) or DTNB (5,5'-dithiobis-2-nitrobenzoate) confirmed that the profound inhibition produced is associated with an important alteration of the quaternary structure of GS, and suggest that Cys-159 might be the residue responsible for the enzyme inhibition. All these results suggest that the Cys-159 residue is essential for the enzyme structure. The results are also consistent with previous reports based on classical biochemistry studies indicating the presence of essential cysteinyl residues for the enzyme activity of higher plant GS.


Assuntos
Cisteína/metabolismo , Glutamato-Amônia Ligase/química , Phaseolus/enzimologia , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Biocatálise/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Ativação Enzimática/efeitos dos fármacos , Escherichia coli , Glutamato-Amônia Ligase/metabolismo , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Proteínas Mutantes/isolamento & purificação , Proteínas Mutantes/metabolismo , Phaseolus/efeitos dos fármacos , Estrutura Secundária de Proteína , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Análise de Sequência de Proteína , Espectrometria de Fluorescência , Relação Estrutura-Atividade , Reagentes de Sulfidrila/farmacologia , Fatores de Tempo
10.
Biochem Biophys Res Commun ; 350(2): 424-9, 2006 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-17010935

RESUMO

Lengsin (LGS) is an abundant transcript in the human lens, encoding a predicted polypeptide similar to glutamine synthetase (GS). We show that a major alternatively spliced product of LGS codes for a 57kDa polypeptide that assembles into a catalytically inactive dodecamer, cross-reacts with anti-GS antibodies, and is expressed at high levels in transparent, but not cataractous, human lenses. Based on this characteristic oligomeric organization, preferential expression in the transparent lens, and amyloid-beta association previously reported for GS, a potential chaperone-like role of LGS has been investigated. We find that LGS has six binding sites for the hydrophobic surface probe bis-ANS and relieves cellular toxicity caused by amyloid-beta expression in a folding-impaired yeast mutant. While documenting the structural similarity between LGS and prokaryotic GS-I, the data rule out any involvement of lengsin in glutamine biosynthesis and suggest an unrelated role that may be important for lens homeostasis and transparency.


Assuntos
Proteínas do Olho/fisiologia , Glutamato-Amônia Ligase/fisiologia , Cristalino/metabolismo , Processamento Alternativo , Peptídeos beta-Amiloides/metabolismo , Naftalenossulfonato de Anilina/química , Catarata/metabolismo , Reações Cruzadas , Proteínas do Olho/química , Proteínas do Olho/genética , Corantes Fluorescentes , Glutamato-Amônia Ligase/química , Glutamato-Amônia Ligase/genética , Glutamato-Amônia Ligase/imunologia , Humanos , Fragmentos de Peptídeos/metabolismo , Filogenia
11.
Rev. cuba. endocrinol ; 6(2): 89-96, jul.-dic. 1995. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-168799

RESUMO

Se realizo una encuesta a todas las mujeres diabeticas enedad reproductiva (15-49 anos) residentes en un area de salud urbana de Ciudad de La Habana para explorar sus conocimientos acerca del uso y eficiencia de diferentes metodos contraceptivos y su influencia sobre el control metabolico de la diabetes mellitus. El nivel de conocimiento al respecto fue aceptable, sobre todoen relacion con los contraceptivos hormonales. El metodo mas usado y consideradomas eficaz fue la esterilizacion, mientras los considerados menos daninos para la enfermedad fueron los metodos de barrera, especificamente el condon, aunque paradojicamente, es poco usado por las parejas de las mujeres entrevistadas. Se insiste en la necesidad de una labor educacional mas intensa en los cuidados contraceptivos de la mujer diabetica por parte de los Medicos de la Familia, endocrinologos y educadores


Assuntos
Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Anticoncepção/efeitos adversos , Anticoncepção/métodos , Diabetes Mellitus , Complicações na Gravidez , Atenção Primária à Saúde , Anormalidades Congênitas/prevenção & controle , Planejamento Familiar , Educação Sexual
12.
Rev. cuba. endocrinol ; 5(1): 57-62, ene.-jun. 1994. ilus
Artigo em Espanhol | LILACS | ID: lil-207875

RESUMO

El control metabólico estricto del paciente diabético readunda en su beneficio pues retarda las complicaciones propias de esta enfermedad, se hace necesario por tanto, utilizar métodos que estén al alcance de todos y, a la vez, que sean sencillos y precisos para valorar su control. La determinación de la glicemia seriada por papel de filtro resulta una técnica utilizada en la clínica con buenos resultados. Se comprueba que los resultados obtenidos cuando la muestra es tomada por el propio paciente son satisfactorios. En el estudio del perfil glicémico realizado en sus hogares se observan períodos hipogllicémicos e hieprglicémicos severos en el grupo de diabéticos, que no se hubieran detectado por el método convencional. El método resultó ampliamente aceptado por todos aquellos pacientes deseosos de mantener un buen control


Assuntos
Automonitorização da Glicemia/métodos , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus/sangue , Técnicas In Vitro
13.
An. bras. dermatol ; 67(4): 159-65, jul.-ago. 1992.
Artigo em Português | LILACS | ID: lil-113173

RESUMO

Com base em importantes trabalhos da literatura internacional realizados na última década sobre Pitiríase versicolor, os autores fazem uma extensa revisäo bibliográfica do tema, abordando especialmente aspectos históricos, etiológicos, etiopatogênicos, epidemiológicos, histopatológicos, clínicos, diagnósticos e terapêuticos


Assuntos
Humanos , Masculino , Feminino , Dermatite Seborreica/microbiologia , Malassezia/imunologia , Micose Fungoide/ultraestrutura , Pitiríase/etiologia , Tinha Versicolor/microbiologia , Glândulas Sebáceas/lesões , Pitiríase/diagnóstico , Pitiríase/epidemiologia , Pitiríase/tratamento farmacológico
14.
Rev. cuba. endocrinol ; 3(1): 29-34, ene.-jun. 1992. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-120921

RESUMO

La necesidad de mantener un buen control de la glicemia del paciente diabético tiene gran importancia principalmente en aquéllos insulinodependientes. Esto justifica el desarrollo de métodos precisos y sencillos para este fin. La utilización del papel de filtro para determinar glucosa en sangre, tiene evidentes ventajas sobre los métodos utilizados con orina, por ello, nos propusimos montar y validar este método para utilizarlo en la práctica clínica. El estudio realizado demostró tener la precisión y exactitud requeridas, en el ensayo de la estabilidad en el tiempo y temperatura se encontró que no hubo variación significativa a los 13 días lo cual resulta ventajoso. El ensayo fue validado en cuanto a precisión, exactitud y recuperación y se tomó como referencia el micrométodo en sangre capilar utilizado habitualmente


Assuntos
Humanos , Glicemia/análise , Diabetes Mellitus/sangue , Glucose Oxidase , Fitas Reagentes
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