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1.
Front Nutr ; 9: 874254, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35449538

RESUMO

L-Theanine is commonly used to improve sleep quality through inhibitory neurotransmitters. On the other hand, Mg2+, a natural NMDA antagonist and GABA agonist, has a critical role in sleep regulation. Using the caffeine-induced brain electrical activity model, here we investigated the potency of L-theanine and two novel Mg-L-theanine compounds with different magnesium concentrations on electrocorticography (ECoG) patterns, GABAergic and serotonergic receptor expressions, dopamine, serotonin, and melatonin levels. Furthermore, we evaluated the sleep latency and duration in the pentobarbital induced sleep model. We herein showed that L-theanine, particularly its various complexes with magnesium increases the expression of GABAergic, serotonergic, and glutamatergic receptors, which were associated with decreased ECoG frequency, increased amplitude, and enhanced delta wave powers. Besides increased dopamine, serotonin, and melatonin; decreased MDA and increased antioxidant enzyme levels were also observed particularly with Mg-complexes. Protein expression analyses also showed that Mg-L-theanine complexes decrease inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) levels significantly. In accordance with these results, Mg complexes improved the sleep latency and duration even after caffeine administration. As a result, our data indicate that Mg-L-theanine compounds potentiate the effect of L-theanine on sleep by boosting slow-brain waves, regulating brain electrical activity, and increasing neurotransmitter and GABA receptor levels.

2.
Eur Stroke J ; 3(3): 263-271, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31008357

RESUMO

INTRODUCTION: Carotid revascularisation improves haemodynamic compromise in cerebral circulation as an additional benefit to the primary goal of reducing future thromboembolic risk. We determined the effect of carotid artery stenting on cerebral perfusion and oxygenation using a perfusion-weighted MRI algorithm that is based on assessment of capillary transit-time heterogeneity together with other perfusion and metabolism-related metrics. PATIENTS AND METHODS: A consecutive series of 33 patients were evaluated by dynamic susceptibility contrast perfusion-weighted MRI prior to and within 24 h of the endovascular procedure. The level of relative change induced by stenting, and relationship of these changes with respect to baseline stenosis degree were analysed. RESULTS: Stenting led to significant increase in cerebral blood flow (p < 0.001), and decrease in cerebral blood volume (p = 0.001) and mean transit time (p < 0.001); this was accompanied by reduction in oxygen extraction fraction (p < 0.001) and capillary transit-time heterogeneity (p < 0.001), but an overall increase in relative capillary transit-time heterogeneity (RTH: CTH divided by MTT; p = 0.008). No significant change was observed with respect to cerebral metabolic rate of oxygen. The median volume of tissue with MTT > 2s decreased from 24 ml to 12 ml (p = 0.009), with CTH > 2s from 29 ml to 19 ml (p = 0.041), and with RTH < 0.9 from 61 ml to 39 ml (p = 0.037) following stenting. These changes were correlated with the baseline degree of stenosis.Discussion: Stenting improved the moderate stage of haemodynamic compromise at baseline in our cohort. The decreased relative transit-time heterogeneity, which increases following stenting, is probably a reflection of decreased functional capillary density secondary to chronic hypoperfusion induced by the proximal stenosis.Conclusion: Carotid artery stenting, is not only important for prophylaxis of future vascular events, but also is critical for restoration of microvascular function in the cerebral tissue.

3.
J Clin Virol ; 70: 89-92, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26305827

RESUMO

BACKGROUND: Toscana virus (TOSV) is a sandfly-borne pathogen causing febrile diseases and neuroinvasive infections in humans. Definitive diagnosis of TOSV infections frequently requires the detection of viral RNA in cerebrospinal fluid (CSF) or in circulation, which can be achieved prior to seroconversion. OBJECTIVES: To evaluate TOSV excretion in urine and impact of urine as a diagnostic specimen. STUDY DESIGN: A total of 82 plasma, CSF and urine samples were collected from 24 individuals with a preliminary diagnosis of atypical viral encephalitis, where frequent bacterial fungal and viral causes were ruled out. Phlebovirus and WNV nucleic acids were investigated via real-time and nested polymerase chain reaction (PCR) assays. Commercial immunofluorescence assays were employed for viral IgM detection. Amplicons were characterized via cloning and sequencing. RESULTS: Phlebovirus PCR yielded positive results in 7 out of 14 samples that comprise 4 plasma and 3 urine specimens from 3 individuals. Amplicons were characterized as TOSV genotype A. Investigation of the follow-up samples suggested that virus shedding in urine coincides or follows viremia. Despite conserved sequences observed in paired or sequential plasma-urine specimens, L693S substitution in the viral polymerase was characterized in a urine sample. CONCLUSIONS: These preliminary findings indicate that urine can be employed as a additional clinical sample for TOSV RNA detection in suspected cases, especially in individuals where specimens for viral diagnostics during the early stages of the infection are not available.


Assuntos
Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/virologia , Febre por Flebótomos/diagnóstico , Febre por Flebótomos/virologia , RNA Viral/genética , Vírus da Febre do Flebótomo Napolitano/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , Vírus da Febre do Flebótomo Napolitano/classificação , Alinhamento de Sequência
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