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1.
Clin Neurophysiol ; 149: 18-24, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36867915

RESUMO

OBJECTIVE: Focal application of transcranial static magnetic field stimulation (tSMS) is a neuromodulation technique, with predominantly inhibitory effects when applied to the motor, somatosensory or visual cortex. Whether this approach can also transiently interact with dorsolateral prefrontal cortex (DLPFC) function remains unclear. The suppression of habitual or competitive responses is one of the core executive functions linked to DLPFC function. This study aimed to assess the impact of tSMS on the prefrontal contributions to inhibitory control and response selection by means of a RNG task. METHODS: We applied 20 min of tSMS over the left DLPFC of healthy subjects, using a real/sham cross-over design, during performance of a RNG task. We used an index of randomness calculated with the measures of entropy and correlation to assess the impact of stimulation on DLPFC function. RESULTS: The randomness index of the sequences generated during the tSMS intervention was significantly higher compared to those produced in the sham condition. CONCLUSIONS: Our results indicate that application of tSMS transiently modulates specific functional brain networks in DLPFC, which indicate a potential use of tSMS for treatment of neuropsychiatric disorders. SIGNIFICANCE: This study provides evidence for the capacity of tSMS for modulating DLPFC function.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Córtex Visual , Humanos , Córtex Pré-Frontal Dorsolateral , Estimulação Magnética Transcraniana/métodos , Função Executiva , Campos Magnéticos , Córtex Pré-Frontal/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos
2.
J Sci Food Agric ; 103(7): 3540-3549, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36719279

RESUMO

BACKGROUND: Natural wine (NW) lacks an official or agreed definition, but it can be generally described as a wine produced with organic or biodynamic grapes with minimal intervention in the cellar, and with minimal or no use of oenological additives. The present study aimed to test the hypotheses that self-defined NWs differ from conventional wines (CW) in their chemical composition and main sensory characteristics. The levels of conventional oenological parameters, turbidity, biogenic amines, ochratoxin A, ethyl carbamate, sulphites, chlorides, some metals, major, trace and Strecker aldehyde volatile compounds were determined in 28 wines, including natural and conventional Spanish commercial white wines. Wines were also sensory described following a labelled free sorting task. RESULTS: NWs presented higher pH, volatile acidity (VA) and turbidity values, and a more intense yellow colour, whereas they have a lower malic acid content compared to theor conventional counterparts. NWs presented lower levels of total sulphur dioxide but significantly higher levels of biogenic amine putrescine, although both compounds are within the legal limits in all cases. None of the dimensions of the similarity space discriminated NWs from CWs. However, 70% of the NWs were grouped on the basis of various aromatic defects related to their higher content in 4-ethylphenols and VA. The remaining 30% were not differentiated from their conventional counterparts. CONCLUSION: It could be confirmed that NW can be globally differentiated from CW with respect to to their chemical and their sensory profiles, whereas the content in toxicants was not significantly different, with the exception of total sulphur dioxide and putrescine levels. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Vitis , Vinho , Vinho/análise , Putrescina , Dióxido de Enxofre , Vitis/química , Agricultura
3.
Biogerontology ; 13(4): 399-411, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22580750

RESUMO

It is known that a global decrease in food ingestion (dietary restriction, DR) lowers mitochondrial ROS generation (mitROS) and oxidative stress in young immature rats. This seems to be caused by the decreased methionine ingestion of DR animals. This is interesting since isocaloric methionine restriction in the diet (MetR) also increases, like DR, rodent maximum longevity. However, it is not known if old rats maintain the capacity to lower mitROS generation and oxidative stress in response to MetR similarly to young immature animals, and whether MetR implemented at old age can reverse aging-related variations in oxidative stress. In this investigation the effects of aging and 7 weeks of MetR were investigated in liver mitochondria of Wistar rats. MetR implemented at old age decreased mitROS generation, percent free radical leak at the respiratory chain and mtDNA oxidative damage without changing oxygen consumption. Protein oxidation, lipoxidation and glycoxidation increased with age, and MetR in old rats partially or totally reversed these age-related increases. Aging increased the amount of SIRT1, and MetR decreased SIRT1 and TFAM and increased complex IV. No changes were observed in the protein amounts of PGC1, Nrf2, MnSOD, AIF, complexes I, II and III, and in the extent of genomic DNA methylation. In conclusion, treating old rats with isocaloric short-term MetR lowers mitROS production and free radical leak and oxidative damage to mtDNA, and reverses aging-related increases in protein modification. Aged rats maintain the capacity to lower mitochondrial ROS generation and oxidative stress in response to a short-term exposure to restriction of a single dietary substance: methionine.


Assuntos
Envelhecimento/metabolismo , Metionina/deficiência , Mitocôndrias Hepáticas/enzimologia , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Animais , DNA Mitocondrial/metabolismo , Masculino , Modelos Animais , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Proteínas de Ligação a RNA/metabolismo , Ratos , Ratos Wistar , Sirtuína 1/metabolismo , Superóxido Dismutase/metabolismo , Fatores de Transcrição/metabolismo
4.
J Bioenerg Biomembr ; 43(6): 699-708, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22006472

RESUMO

Methionine dietary restriction (MetR), like dietary restriction (DR), increases rodent maximum longevity. However, the mechanism responsible for the retardation of aging with MetR is still not entirely known. As DR decreases oxidative damage and mitochondrial free radical production, it is plausible to hypothesize that a decrease in oxidative stress is the mechanism for longevity extension with MetR. In the present investigation male Wistar rats were subjected to isocaloric 40% MetR during 7 weeks. It was found that 40% MetR decreases heart mitochondrial ROS production at complex I during forward electron flow, lowers oxidative damage to mitochondrial DNA and proteins, and decreases the degree of methylation of genomic DNA. No significant changes occurred for mitochondrial oxygen consumption, the amounts of the four respiratory complexes (I to IV), and the mitochondrial protein apoptosis-inducing factor (AIF). These results indicate that methionine can be the dietary factor responsible for the decrease in mitochondrial ROS generation and oxidative stress, and likely for part of the increase in longevity, that takes place during DR. They also highlight some of the mechanisms involved in the generation of these beneficial effects.


Assuntos
Metilação de DNA , DNA Mitocondrial/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Metionina , Mitocôndrias Cardíacas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Fator de Indução de Apoptose/metabolismo , Dano ao DNA , Longevidade , Masculino , Oxirredução , Ratos , Ratos Wistar , Fatores de Tempo
5.
J Bioenerg Biomembr ; 43(4): 377-86, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21748404

RESUMO

Dietary methionine restriction and supplementation in mammals have beneficial (antiaging) and detrimental effects respectively, which have been related to chronic modifications in the rate of mitochondrial ROS generation. However it is not known if methionine or its metabolites can have, in addition, direct effects on the rate of mitochondrial ROS production. This is studied here for the methionine cycle metabolites S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), homocysteine and methionine itself in isolated rat liver, kidney, heart, and brain mitochondria. The results show that methionine increases ROS production in liver and kidney mitochondria, homocysteine increases it in kidney and decreases it in the other three organs, and SAM and SAH have no effects. The variations in ROS production are localized at complexes I or III. These changes add to previously described chronic effects of methionine restriction and supplementation in vivo.


Assuntos
Homocisteína/metabolismo , Metionina/metabolismo , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Homocisteína/farmacologia , Peróxido de Hidrogênio/metabolismo , Masculino , Metionina/farmacologia , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Ratos , Ratos Wistar
6.
Cultura (Asoc. Docentes Univ. San Martín Porres) ; 26(22): 415-425, dic. 2008. tab, graf
Artigo em Espanhol | LIPECS | ID: biblio-1107724

RESUMO

Esta investigación trata de establecer, si existe jerarquización de valores en base a la importancia que le dan los profesores inherentes a la enseñanza de niños con Necesidades Educativas Especiales.


This investigation try to establish if exists hierarchic values in base the importance that give the teachers, inherent the teaching of children with Special Educative Necessities.


Assuntos
Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Docentes , Educação Inclusiva , Estudantes , Relações Interpessoais , Valores Sociais , Epidemiologia Descritiva , Peru
7.
Rev. Ecuat. cancerol ; 2(3): 62-7, dic. 1995. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-188862

RESUMO

El 3 metilcolantreno es un carcinogeno pluripotente. el autor ha logrado inducir en el ratón Mus musculus, fibrosarcomas y carcinomas epidermoides por inoculación subcutánea en el primer caso y por escarificación de la piel, en el segundo caso. El porcentaje de fibrosarcomas es alto (90 por ciento), mientras que en el caso de carcinomas escamosas es bajo (9 por ciento). Se considera al ratón Mus musculus como modelo experimental, a pesar de ser una estirpe no significa, pues los fibrosarcomas crecen progresiva y uniformemente, como si se trata de animales singénicos. Este patron de crecimiento servirá para ensayos experimentales, terapéuticos sobre todo. Se obtienen además datos curiosos (cambio de color de ojos, pigmentación e hiperrofia de glándulas mamarias y retardo de crecimiento corporal de algunos animales) que podrían despertar el ánimo del investigador en orden a esclarecer los fenómenos biológicos involucrados.


Assuntos
Humanos , Carcinoma de Células Escamosas/complicações , Fibrossarcoma , Metilcolantreno/administração & dosagem , Camundongos
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