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1.
An Acad Bras Cienc ; 95(2): e20201853, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37556705

RESUMO

The present study verified the presence of phytoconstituents and evaluated antioxidant (DPPH, FRAP, NO and TBARS tests) and antiglycation (REM test) activities of unconventional wild edible fruits Chrysophyllum cainito, Hancornia speciosa and Plinia glomerata. It was verified the presence of phenolic compounds for all fruits and flavonoids were observed only for C. cainito, which presented in its peel the highest total phenols (90.34 µg GAE mg-1) and flavonoids (30.4 µg RE mg-1) content. Sugar concentration was significant for all fruits, where H. speciosa showed the highest reducing sugar content (576.12 mg g-1) and C. cainito pulp showed the highest total sugar content (858.67 mg g-1). All fruits presented vitamin C and carotenoids, highlighting P. glomerata with the best results for ascorbic acid (2260.94 mg 100 g-1) and carotenoids (59.62 µg g-1). Extracts presented antioxidant activity, highlighting C. cainito peel that presented 65.64% (DPPH), 231.34 µM TE L-1 (FRAP), 49.34% (NO) and 22.56% (TBARS), while in antiglycation evaluation, P. glomerata showed evident activity. Therefore, it was possible to determine different phytoconstituents, and antioxidant and antiglycation activities of the fruits. These data provide subsidies for application of these fruits in new studies, to increase knowledge and preservation of these species.


Assuntos
Apocynaceae , Sapotaceae , Antioxidantes/análise , Frutas/química , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Extratos Vegetais/química , Flavonoides/farmacologia , Flavonoides/análise , Ácido Ascórbico/farmacologia , Ácido Ascórbico/análise , Fenóis/farmacologia , Fenóis/análise , Carotenoides/farmacologia , Carotenoides/análise , Açúcares/análise
2.
Opt Lett ; 47(21): 5489-5492, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37219251

RESUMO

In this work, we analyze different types of recurrent neural networks (RNNs) working under several different parameters to best model the nonlinear optical dynamics of pulse propagation. Here we studied the propagation of picosecond and femtosecond pulses under distinct initial conditions going through 13 m of a highly nonlinear fiber and demonstrated the application of two RNNs returning error metrics such as normalized root mean squared error (NRMSE) as low as 9%. Those results were further extended for a dataset outside the initial pulse conditions used on the RNN training, and the best-proposed network was still able to achieve a NRMSE below 14%. We believe that this study can contribute to a better understanding of building RNNs employed for modeling nonlinear optical pulse propagation and of how the peak power and nonlinearity affect the prediction error.

3.
Eur J Pharmacol ; 866: 172819, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31758939

RESUMO

The role of the renin-angiotensin-aldosterone system and arginine vasopressin (AVP) as humoral components in maintaining blood pressure (BP) during hemorrhagic shock (HS) is well established. However, little is known about the role of angiotensin II (Ang II) and AVP in the control of preganglionic sympathetic neuron activity. We studied the effects evoked by spinal Ang II type I (AT1) and V1a receptors antagonism on cardiovascular and sympathetic responses during HS. A catheter (PE-10) was inserted into the subarachnoid space and advanced to the T10-11 vertebral level in urethane-anesthetized rats. The effects of HS on BP, heart rate (HR), and renal and splanchnic sympathetic nerve activity (rSNA and sSNA, respectively) were analyzed in the presence or absence (HS rats) of intrathecally injected losartan (HS-Los rats) or V1a antagonist (HS-V1a rats). The right femoral artery was catheterized for bleeding. Using a 5 ml syringe, hemorrhage was maintained continuously until a BP reduction of ~50 mmHg was achieved. We found that bleeding caused a reflex increase in HR, rSNA and sSNA in the HS rats. However, such responses were attenuated in the HS-Los rats. HS-V1a rats showed a reflex increase in HR, rSNA and sSNA in terms of frequency (spikes/s) but not in amplitude. Nevertheless, the BP recovery of the groups was similar. Our data showed that spinal AT1 receptors are essential for sympathoexcitation during the acute phase of HS. Moreover, spinal AVP seems to be a neuromodulator that controls the recruitment of spinal sympathetic vasomotor neurons during the acute phase of HS.


Assuntos
Receptor Tipo 1 de Angiotensina/metabolismo , Receptores de Vasopressinas/metabolismo , Choque Hemorrágico/fisiopatologia , Medula Espinal/metabolismo , Sistema Nervoso Simpático/fisiopatologia , Doença Aguda , Animais , Pressão Sanguínea , Frequência Cardíaca , Masculino , Ratos Wistar , Choque Hemorrágico/metabolismo
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