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1.
Brain Sci ; 14(1)2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38248273

RESUMO

Apraxia of speech is a persistent speech motor disorder that affects speech intelligibility. Studies on speech motor disorders with transcranial Direct Current Stimulation (tDCS) have been mostly directed toward examining post-stroke aphasia. Only a few tDCS studies have focused on apraxia of speech or childhood apraxia of speech (CAS), and no study has investigated individuals with CAS and Trisomy 21 (T21, Down syndrome). This N-of-1 randomized trial examined the effects of tDCS combined with a motor learning task in developmental apraxia of speech co-existing with T21 (ReBEC RBR-5435x9). The accuracy of speech sound production of nonsense words (NSWs) during Rapid Syllable Transition Training (ReST) over 10 sessions of anodal tDCS (1.5 mA, 25 cm) over Broca's area with the cathode over the contralateral region was compared to 10 sessions of sham-tDCS and four control sessions in a 20-year-old male individual with T21 presenting moderate-severe childhood apraxia of speech (CAS). The accuracy for NSW production progressively improved (gain of 40%) under tDCS (sham-tDCS and control sessions showed < 20% gain). A decrease in speech severity from moderate-severe to mild-moderate indicated transfer effects in speech production. Speech accuracy under tDCS was correlated with Wernicke's area activation (P3 current source density), which in turn was correlated with the activation of the left supramarginal gyrus and the Sylvian parietal-temporal junction. Repetitive bihemispheric tDCS paired with ReST may have facilitated speech sound acquisition in a young adult with T21 and CAS, possibly through activating brain regions required for phonological working memory.

2.
Front Hum Neurosci ; 17: 1116890, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37520930

RESUMO

To the best of our knowledge, neurophysiological markers indicating changes induced by non-invasive brain stimulation (NIBS) on cognitive performance, especially one of the most investigated under these procedures, working memory (WM), are little known. Here, we will briefly introduce frontal midline theta (FM-theta) oscillation (4-8 Hz) as a possible indicator for NIBS effects on WM processing. Electrophysiological recordings of FM-theta oscillation seem to originate in the medial frontal cortex and the anterior cingulate cortex, but they may be driven more subcortically. FM-theta has been acknowledged to occur during memory and emotion processing, and it has been related to WM and sustained attention. It mainly occurs in the frontal region during a delay period, in which specific information previously shown is no longer perceived and must be manipulated to allow a later (delayed) response and observed in posterior regions during information maintenance. Most NIBS studies investigating effects on cognitive performance have used n-back tasks that mix manipulation and maintenance processes. Thus, if considering FM-theta as a potential neurophysiological indicator for NIBS effects on different WM components, adequate cognitive tasks should be considered to better address the complexity of WM processing. Future research should also evaluate the potential use of FM-theta as an index of the therapeutic effects of NIBS intervention on neuropsychiatric disorders, especially those involving the ventral medial prefrontal cortex and cognitive dysfunctions.

3.
Rev Assoc Med Bras (1992) ; 67(11): 1616-1621, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34730674

RESUMO

OBJECTIVE: The aim of this study was to compare the results obtained using SpectroView® (SV) and J-Magnetic Resonance User Interface (jMRUI) from the same magnetic resonance (MR) spectroscopy of hydrogen data. METHODS: Data from 23 males with alcohol use disorder (AUD) and 23 healthy non-AUD males were acquired by a 1.5 Tesla MR using a PRESS sequence (TE=30 ms) in four voxels located in the right frontal and left frontal (RF and LF) lobes, and posterior cingulate (AC and PC). The ratio of the signals from both N-acetyl-aspartate (NAA) and choline (Cho) over creatine (Cr) was calculated automatically using SV and semiautomatically by an expert neuroradiologist using jMRUI. The software' agreement was calculated by the 95% limits of agreement (LoA) of the ratio of the obtained values. RESULTS: The standard deviation was greater in jMRUI than in SV. Although there was a correlation between the results from both methods, it was not possible to predict their variance from one another. Additionally, the 95% LoA showed that jMRUI values were expected to vary from 38 to 190% of those obtained using SV for NAA/Cr in RF of AUD subjects and from 48 to 196% for NAA/Cr in CA of non-AUD individuals. CONCLUSIONS: The difference between the methods may represent clinically significant magnitudes. We suggest the use of the same method when comparing spectroscopic data. We also suggest that in clinical practice, the automatic method should be preferred.


Assuntos
Creatina , Imageamento por Ressonância Magnética , Colina , Humanos , Espectroscopia de Ressonância Magnética , Masculino
5.
Trials ; 22(1): 647, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34548110

RESUMO

BACKGROUND: Transcranial direct current stimulation (tDCS) has the potential to modulate cortical excitability and enhance the effects of walking training in people with Parkinson's disease. This study will examine the efficacy of the addition of tDCS to a task-specific walking training to improve walking and mobility and to reduce falls in people with Parkinson's disease. METHODS: This is a two-arm, prospectively registered, randomized trial with concealed allocation, blinded assessors, participants and therapists, and intention-to-treat analysis. Twenty-four individuals with Parkinson's disease, categorized as slow or intermediate walkers (walking speeds ≤ 1.0 m/s), will be recruited. The experimental group will undertake a 30-min walking training associated with tDCS, for 4 weeks. The control group will undertake the same walking training, but with sham-tDCS. The primary outcome will be comfortable walking speed. Secondary outcomes will include walking step length, walking cadence, walking confidence, mobility, freezing of gait, fear of falling, and falls. Outcomes will be collected by a researcher blinded to group allocation at baseline (week 0), after intervention (week 4), and 1 month beyond intervention (week 8). DISCUSSION: tDCS associated with walking training may help improve walking of slow and intermediate walkers with Parkinson's disease. If walking is enhanced, the benefits may be accompanied by better mobility and reduced fear of falling, and individuals may experience greater free-living physical activity at home and in the community. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials (ReBEC) RBR-6bvnx6 . Registered on September 23, 2019.


Assuntos
Transtornos Neurológicos da Marcha , Doença de Parkinson , Estimulação Transcraniana por Corrente Contínua , Acidentes por Quedas/prevenção & controle , Terapia por Exercício , Medo , Humanos , Doença de Parkinson/diagnóstico , Doença de Parkinson/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Caminhada
6.
Int J Neuropsychopharmacol ; 24(4): 256-313, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32710772

RESUMO

BACKGROUND: Transcranial direct current stimulation has shown promising clinical results, leading to increased demand for an evidence-based review on its clinical effects. OBJECTIVE: We convened a team of transcranial direct current stimulation experts to conduct a systematic review of clinical trials with more than 1 session of stimulation testing: pain, Parkinson's disease motor function and cognition, stroke motor function and language, epilepsy, major depressive disorder, obsessive compulsive disorder, Tourette syndrome, schizophrenia, and drug addiction. METHODS: Experts were asked to conduct this systematic review according to the search methodology from PRISMA guidelines. Recommendations on efficacy were categorized into Levels A (definitely effective), B (probably effective), C (possibly effective), or no recommendation. We assessed risk of bias for all included studies to confirm whether results were driven by potentially biased studies. RESULTS: Although most of the clinical trials have been designed as proof-of-concept trials, some of the indications analyzed in this review can be considered as definitely effective (Level A), such as depression, and probably effective (Level B), such as neuropathic pain, fibromyalgia, migraine, post-operative patient-controlled analgesia and pain, Parkinson's disease (motor and cognition), stroke (motor), epilepsy, schizophrenia, and alcohol addiction. Assessment of bias showed that most of the studies had low risk of biases, and sensitivity analysis for bias did not change these results. Effect sizes vary from 0.01 to 0.70 and were significant in about 8 conditions, with the largest effect size being in postoperative acute pain and smaller in stroke motor recovery (nonsignificant when combined with robotic therapy). CONCLUSION: All recommendations listed here are based on current published PubMed-indexed data. Despite high levels of evidence in some conditions, it must be underscored that effect sizes and duration of effects are often limited; thus, real clinical impact needs to be further determined with different study designs.


Assuntos
Encefalopatias/terapia , Transtornos Mentais/terapia , Dor/reabilitação , Guias de Prática Clínica como Assunto/normas , Estimulação Transcraniana por Corrente Contínua/normas , Medicina Baseada em Evidências , Humanos
7.
Med Hypotheses ; 144: 109916, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32526508

RESUMO

Parkinson's disease (PD) is one of the most prevalent neurodegenerative diseases in the world, with a high degree of disability. Among the various therapeutic possibilities, brain stimulation appears in a promising approach, with deep brain stimulation (DBS) being the best described and successful, yet it has the limitation of being invasive. In this context we present transcranial direct current stimulation (tDCS), a non-invasive treatment that brings a new perspective when thinking about treatment of neurological diseases. It is easy to handle, low cost, few side effects and good adherence to patients. TDCS presents good evidence for clinical practice, but when it comes to PD the results obtained are inconclusive and some protocols have not yet been tested. In this hypothesis we propose that the use of tDCS applied in the supplemental motor areas, together with a gait training, can facilitate the motor learning and modulate the neurons for better potentiation of the exercises together with patients with walking difficulties due to PD.


Assuntos
Córtex Motor , Doença de Parkinson , Estimulação Transcraniana por Corrente Contínua , Marcha , Humanos , Doença de Parkinson/terapia , Caminhada
8.
Front Psychiatry ; 11: 469, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508693

RESUMO

The brain-derived neurotrophic factor (BDNF) is a neurotrophin recognized to play a major role in neuroplastic modifications associated to drug abuse, being involved in various behavioral changes found in drug use disorders, such as drug sensitization, craving and relapses. These neuroplastic changes were shown to affect the prefrontal cortex functions, which can be briefly measured through cognitive tests such as the Frontal Assessment Battery (FAB). In this study we investigated the BDNF mRNA expression in peripheral blood lymphocytes of crack-cocaine use disorder (CUD) and alcohol use disorder (AUD) patients, after drug detoxification treatment, using a real-time PCR approach and examining its association to FAB performance. BDNF mRNA expression was found to be higher by 2.25-fold in CUD patients and by 2-fold in the AUD patients when normalized to controls, and these values were found to be associated with FAB scores. This preliminary study evaluates, for the first time, BDNF mRNA expression in leukocytes and its relationship to FAB scores in crack-cocaine and alcohol use disorder patients.

9.
Front Psychiatry ; 10: 196, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31024358

RESUMO

Alcohol consumption seems to affect corpus callosum morphometry irrespectively of an alcohol use disorder (AUD) diagnosis. The present study examined the relationship between corpus callosum (CC) subregion volumes and alcohol use patterns in AUD and non-AUD subjects. Twenty-two male AUD patients and 23 healthy matched non-AUD subjects were recruited from March 2016 to July 2017. Volumetric data were acquired through Magnetic Resonance and analyzed by the FreeSurfer software. AUD subjects were in abstinence for 45.1 days ± 36.8 (SD), consumed higher amounts of alcohol and presented higher AUDIT scores than controls (p < 0.0001). A multivariate analysis corrected by age and tobacco use indicated that AUD patients presented smaller CC volumes compared to non-AUD subjects (p < 0.01), except for the posterior subregion. A multiple regression analysis corrected by age and tobacco use including CC volumes from all subjects and the amount of daily alcohol ingestion as variables indicated that anterior CC volume was negatively (p < 0.001) associated to alcohol consumption. This study demonstrated that CC subregions were smaller in AUD subjects, as expected, and that the volume of the anterior segment was inversely associated to increasing daily amounts of alcohol, indicating greater frontal region vulnerability to harmful alcohol effects.

10.
Behav Brain Res ; 362: 208-212, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30654123

RESUMO

Anodal Direct Current Stimulation (DC) over prefrontal cortex improves working memory. This study investigated the influence of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) on prefrontal anodal DC-induced effects on spatial working memory and GAP-43 expression. Male Wistar rats well-trained in radial maze procedures received five sessions of anodal epidural DC stimulation (eDCS: 400 µA, 13 min, one daily session) over the left mPFC, or a respective sham procedure, and afterwards they received a single dose (1 mg/kg) of perampanel (PRP), an AMPARs antagonist, or vehicle 30 min before the performance of 4-h delayed task. The prefrontal cortex (PFC) and hippocampus (HPC) were removed 24-h later and GAP-43 (growth-associated protein) expression was measured by Western blot analysis. Repetitive eDCS decreased the number of errors in the 4-h post-delay performance (p < 0.05) and increased the expression of GAP-43 (p < 0.01) in the PFC when compared to sham stimulation. These behavioral and prefrontal molecular changes induced by the repetitive eDCS seem to involve AMPAR activity, because they were abolished when AMPARs were blocked by PRP (p < 0.01 and 0.05, respectively). Besides, in the HPC, changes of GAP-43 expression induced by eDCS was only seen when AMPARs were blocked by PRP. Therefore, the neuronal plasticity involving AMPARs may underlie, at least in part, the improving of spatial working memory and GAP-43 expression induced by the repetitive anodal prefrontal DC stimulation.


Assuntos
Proteína GAP-43/efeitos dos fármacos , Memória de Longo Prazo/efeitos dos fármacos , Piridonas/farmacologia , Receptores de AMPA/antagonistas & inibidores , Animais , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória de Curto Prazo/efeitos dos fármacos , Memória de Curto Prazo/fisiologia , Plasticidade Neuronal/efeitos dos fármacos , Plasticidade Neuronal/fisiologia , Nitrilas , Córtex Pré-Frontal/efeitos dos fármacos , Ratos Wistar , Estimulação Transcraniana por Corrente Contínua/métodos
11.
Front Psychiatry ; 9: 563, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30464749

RESUMO

Excessive and long-term alcohol consumption produce metabolic changes, such as of choline, in many brain regions in alcohol use disorder (AUD) and in non-AUD subjects as well. This study examined the association of choline proportion in the prefrontal cortex with pattern of alcohol use in AUD patients. The choline metabolite was acquired through a single voxel Proton Magnetic Resonance Spectroscopy (1H MRS). Between-groups comparison corrected by age showed that the ratio of Choline/Creatine (Cho/Cr) was significantly smaller (p = 0.005) in the Left Prefrontal (LPF) of AUD patients when compared to paired non-AUD subjects. A multiple regression analysis corrected by age showed that decreasing ratios of Cho/Cr in the LPF was associated with increasing amount of alcohol consumption in drinks per day (p < 0.01) in AUD patients. Rates of Cho/Cr in the LPF was inversely related to amounts of alcohol consumption possibly indicating the severity of the AUD. Thus, low proportion of Cho/Cr in the LPF could indicate more severe AUD (higher alcohol intake).

12.
Front Pharmacol ; 9: 1198, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30405414

RESUMO

Background: Non-invasive brain stimulation such as transcranial direct current stimulation (tDCS) has been investigated as additional therapeutic tool for drug use disorder. In a previous study, we showed that five sessions of tDCS applied bilaterally over the dorsolateral prefrontal cortex (dlPFC) reduced craving to the use of crack-cocaine in inpatients from a specialized clinic. In the present study, we examine if an extended number of sessions of the same intervention would reduce craving even further and affect also relapses to crack-cocaine use. Methods: A randomized, double-blind, sham-controlled, clinical trial with parallel arms was conducted (https://clinicaltrials.gov/ct2/show/NCT02091167). Crack-cocaine patients from two private and one public clinics for treatment of drug use disorder were randomly allocated to two groups: real tDCS (5 cm × 7 cm, 2 mA, for 20 min, cathodal over the left dlPFC and anodal over the right dlPFC, n = 19) and sham-tDCS (n = 16). Real or sham-tDCS was applied once a day, every other day, in a total of 10 sessions. Craving was monitored by a 5-item obsessive compulsive drinking scale once a week (one time before, three times during and once after brain stimulation) over about 5 weeks and relapse was monitored after their discharge from clinics for up to 60 days. Results: Craving scores progressively decreased over five measurements in both sham- and real tDCS groups. Corrected Hedges' within-group (initial and final) effect sizes of craving scores were of 0.77 for the sham-tDCS and of 0.97 for the real tDCS group. The between-groups effect size was of 0.34, in favor of the real tDCS group over sham-tDCS group. Relapse rates were high and quite similar between groups in the 30- and 60-days follow-up after discharge from the hospital. Conclusion: Extended repetitive bilateral tDCS over the dlPFC had no add-on effects over regular treatment when considering craving and relapses to the crack-cocaine use in a sample of crack-cocaine patients with severe use disorder. Different tDCS montages targeting other cortical regions and perhaps additional extension of sessions need to be investigated to reach more efficiency in managing craving and relapses to crack-cocaine use.

13.
Front Pharmacol ; 9: 1205, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30405417

RESUMO

FosB gene heterodimerizes with Jun family proteins to form activator protein 1 (AP-1) complexes that bind to AP-1 sites in responsive genes to regulate transcription in all cells. The genic expression of FosB seems to be modified after long time exposure to drugs of abuse and these changes may be involved in craving and addicted behavior. This study investigated the FosB mRNA expression in peripheral blood lymphocytes of drug addicted patients using real-time PCR approach. Thus, patients with crack-cocaine use disorder (CUD, n = 10), alcohol use disorder (AUD, n = 12), and healthy non-addicted subjects (CONT, n = 12) were assessed. FosB mRNA expression was reduced by 1.15-fold in CUD and 2.17-fold in AUD when compared to CONT. Hedge's effect size gs over log FosB/Act was of 0.66 for CUD and of 0.30 for AUD when compared to controls. This study showed that FosB mRNA expression was detected in lymphocytes from peripheral blood for the first time, and it was less expressed in drug addicted patients. This molecular technique may constitute a potential peripheral marker for substance use disorder.

14.
Radiol Bras ; 51(1): 1-7, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29559760

RESUMO

OBJECTIVE: This study aimed to explore the functional connectivity of the default mode network (DMN) in crack-cocaine users, in comparison with that observed in age-matched non-drug-using controls. MATERIALS AND METHODS: Inpatient crack-cocaine users who had been abstinent for at least four weeks and age-matched non-drug-using controls underwent resting state functional magnetic resonance imaging. Images were acquired while the subjects rested with their eyes closed. After data preprocessing, DMNs were defined by spatial independent component analysis and seed-based correlation analysis, by chosen regions of interest centered in the ventral anterior cingulate cortex and in the posterior cingulate cortex. RESULTS: The functional connectivity of the DMN determined by independent component analysis did not differ between the crack-cocaine users and the controls. However, the seed-based correlation analysis seeking a single metric of functional connectivity between specific brain regions showed that the negative connectivity between the ventral anterior cingulate cortex and the left superior parietal lobule was significantly greater in the crack-cocaine users than in the controls. CONCLUSION: The results suggest that selective extrinsic network connectivity of the DMN related to motor and executive function is impaired during crack-cocaine addiction.

15.
Radiol. bras ; 51(1): 1-7, Jan.-Feb. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-896165

RESUMO

Abstract Objective: This study aimed to explore the functional connectivity of the default mode network (DMN) in crack-cocaine users, in comparison with that observed in age-matched non-drug-using controls. Materials and Methods: Inpatient crack-cocaine users who had been abstinent for at least four weeks and age-matched non-drug-using controls underwent resting state functional magnetic resonance imaging. Images were acquired while the subjects rested with their eyes closed. After data preprocessing, DMNs were defined by spatial independent component analysis and seed-based correlation analysis, by chosen regions of interest centered in the ventral anterior cingulate cortex and in the posterior cingulate cortex. Results: The functional connectivity of the DMN determined by independent component analysis did not differ between the crack-cocaine users and the controls. However, the seed-based correlation analysis seeking a single metric of functional connectivity between specific brain regions showed that the negative connectivity between the ventral anterior cingulate cortex and the left superior parietal lobule was significantly greater in the crack-cocaine users than in the controls. Conclusion: The results suggest that selective extrinsic network connectivity of the DMN related to motor and executive function is impaired during crack-cocaine addiction.


Resumo Objetivo: Este estudo teve como objetivo explorar a conectividade funcional da rede de modo padrão em usuários de crack-cocaína comparando-a a controles não usuários da mesma faixa etária. Materiais e Métodos: Usuários de crack-cocaína internados em abstinência por pelo menos quatro semanas e controles não usuários pareados por idade foram submetidos a ressonância magnética funcional em estado de repouso, enquanto descansavam com os olhos fechados. Depois do pré-processamento de dados, a rede de modo padrão foi definida por análise espacial de componentes independentes e análise de correlação baseada em sementes, por regiões de interesse centradas no córtex cingulado anterior ventral e no córtex cingulado posterior. Resultados: A conectividade funcional analisada por componentes independentes não foi diferente entre os usuários de crack- cocaína e os controles pareados por idade. No entanto, a análise de correlação baseada em sementes à procura de uma conectividade funcional métrica única entre regiões específicas do cérebro mostrou uma negatividade significativamente maior da conectividade entre o córtex cingulado anterior ventral e o lóbulo parietal superior esquerdo, quando comparada a controles pareados por idade. Conclusão: Os resultados sugerem que conectividades extrínsecas seletivas da rede de modo padrão relacionadas a funções motoras e executivas podem estar comprometidas na dependência de crack-cocaína.

16.
Neurotox Res ; 34(4): 834-847, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28914428

RESUMO

When burning crack cocaine, the pyrolysis of cocaine generates anhydroecgonine methyl ester (AEME). AEME has been shown to be highly neurotoxic but its effects on cognitive function and oxidative stress are still unknown. Thus, this study investigated the effects of AEME on spatial working memory and on parameters of oxidative stress in the prefrontal cortex, hippocampus, and striatum. First, 18 well-trained rats in 8-arm radial maze (8-RM) procedures received acute intracerebroventricular (icv) administration of AEME at doses of 10, 32, or 100 µg or saline (SAL) in a counterbalanced order and were tested 5 min later in 1-h delayed tasks in the 8-RM. Secondly, separated animals received acute icv administration of AEME at doses of 10 (n = 5), 32 (n = 5), or 100 µg (n = 5) or SAL (n = 5) for analysis of advanced oxidation protein products, thiobarbituric acid, catalase, glutathione peroxidase, and superoxide dismutase. A higher number of errors were seen in the 1-h post-delay performance after AEME 32 µg and AEME 100 µg when compared to SAL. In the striatum, animals receiving AEME 100 µg icv showed increased advanced oxidation protein products levels when compared to 10 µg, and also showed increased activity of glutathione peroxidase enzyme when compared to SAL but also comparing to AEME 32 µg and AEME 10 µg. These results showed that AEME impairs long-term spatial working memory and also induces greater protein oxidation and increased levels of antioxidant enzymes in the striatum.


Assuntos
Cocaína/análogos & derivados , Corpo Estriado/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Memória de Curto Prazo/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Memória Espacial/efeitos dos fármacos , Animais , Cocaína/química , Cocaína/toxicidade , Corpo Estriado/metabolismo , Relação Dose-Resposta a Droga , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Transtornos da Memória/metabolismo , Memória de Curto Prazo/fisiologia , Estresse Oxidativo/fisiologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Ratos Wistar , Memória Espacial/fisiologia
17.
Cereb Cortex ; 27(1): 544-553, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-26494801

RESUMO

The impact of nicotine (NIC) on plasticity is thought to be primarily determined via calcium channel properties of nicotinic receptor subtypes, and glutamatergic plasticity is likewise calcium-dependent. Therefore glutamatergic plasticity is likely modulated by the impact of nicotinic receptor-dependent neuronal calcium influx. We tested this hypothesis for transcranial direct current stimulation (tDCS)-induced long-term potentiation-like plasticity, which is abolished by NIC in nonsmokers. To reduce calcium influx under NIC, we blocked N-methyl-d-aspartate (NMDA) receptors. We applied anodal tDCS combined with 15 mg NIC patches and the NMDA-receptor antagonist dextromethorphan (DMO) in 3 different doses (50, 100, and 150 mg) or placebo medication. Corticospinal excitability was monitored by single-pulse transcranial magnetic stimulation-induced motor-evoked potential amplitudes after plasticity induction. NIC abolished anodal tDCS-induced motor cortex excitability enhancement, which was restituted under medium dosage of DMO. Low-dosage DMO did not affect the impact of NIC on tDCS-induced plasticity and high-dosage DMO abolished plasticity. For DMO alone, the low dosage had no effect, but medium and high dosages abolished tDCS-induced plasticity. These results enhance our knowledge about the proposed calcium-dependent impact of NIC on plasticity in humans and might be relevant for the development of novel nicotinic treatments for cognitive dysfunction.


Assuntos
Dextrometorfano/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Plasticidade Neuronal/efeitos dos fármacos , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Estimulação Transcraniana por Corrente Contínua , Adulto , Análise de Variância , Relação Dose-Resposta a Droga , Potencial Evocado Motor/efeitos dos fármacos , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Masculino , Córtex Motor/efeitos dos fármacos , Córtex Motor/fisiologia , Plasticidade Neuronal/fisiologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/metabolismo , Fatores de Tempo
18.
Vitória; s.n; 2017.
Não convencional em Português | Coleciona SUS | ID: biblio-943358

RESUMO

Introdução: O Programa Mais Médicos (PMM) é o principal programa de provimento médico para a atenção primária (APS). Ainda há importantes lacunas no conhecimento sobre o programa, embora se saiba que o PMM aumentou acesso à APS e possivelmente melhorou alguns indicadores de saúde. O objetivo deste estudo foi identificar as percepções dos médicos que atuam no PMM do ES sobre suas ações e impacto. Metodologia: Aplicou-se questionário estruturado a 204 médicos que atuam no PMM em municípios do ES. O questionário foi aplicado com o apoio dos supervisores do PMM em outubro de 2016. Os dados são analisados a partir de estatística descritiva simples. Resultados: A amostra de médicos corresponde a 47,3% dos profissionais inseridos no PMM no ES no mês de realização da pesquisa. Quanto as características dos entrevistados, tem-se que 115 (57,5%) são mulheres, 90 (44,3%) atuam na Região Metropolitana, estavam em média a 28 meses no PMM (dp=9,3) e tinham em média 40 anos, com mediana de 36 anos. Em relação às atividades regulares desenvolvidas nas unidades de saúde, tem-se que 183 (92,9%) realizavam visitas domiciliares, 173 (88,7%) participavam de atividades comunitárias, 169 (87,1%) desenvolviam atividades de grupo e 173 (88,2%) planejavam ações em equipe. 194 médicos (96,5%) acreditam que o PMM melhorou a APS no município, 113 (57,1%) acreditam que o PMM sofre influência política local que afeta seus resultados e 194 (96,5%) foram bem recebidos em seu local de trabalho. Quanto às ações de apoio ao trabalho do médico no município, 179 (90%) relatam que a especialização Unasus contribuiu para a melhoria da atenção à saúde, sendo que 163 (81,5%) afirmam que as ações da coordenação estadual do PMM influenciaram positivamente a implantação do programa e 183 (90,6%) avaliam positivamente as ações de supervisão do programa. Por fim, todos os médicos entrevistados avaliam positivamente sua entrada no PMM, sendo que 188 (97,9%) acreditam que programas de provimento como o PMM devam existir. Conclusão: Para os médicos que atuam no PMM do ES, o programa tem impacto positivo para a população, sendo que a maioria dos profissionais realiza as atividades previstas e avaliam positivamente as ações de suporte ao seu trabalho, como especializações e supervisões. Os dados deste trabalho sugerem que o PMM tem sido efetivo como programa de provimento médico para a APS.


Assuntos
Avaliação do Impacto na Saúde/métodos , Programas Nacionais de Saúde , Atenção Primária à Saúde , Avaliação de Programas e Projetos de Saúde/métodos , Brasil
20.
J Psychiatr Res ; 83: 137-139, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27614336

RESUMO

This study aimed to examine electrophysiologically the cerebral function under visual cue-reactivity paradigm in crack-cocaine users. This was an exploratory open trial in which young crack-cocaine-users and non-users were clinically examined. The participants' brain activity was analyzed by an event-related potentials procedure under a cue-reactivity paradigm with the random visual presentation of crack-related and neutral images. Nine young male crack-cocaine users and nine age-matched male healthy subjects from research center's neighborhood volunteered themselves to participate in this study. We demonstrated through electrophysiological tools that crack-cocaine users are more likely to show higher brain activity, notably in the frontal lobe region, when processing crack-related images. Though imaging studies have already showed increased brain activity in this paradigm, this data shows that event-related potentials can be an effective tool for brain evaluation in addiction.


Assuntos
Encéfalo/fisiopatologia , Transtornos Relacionados ao Uso de Cocaína , Cocaína Crack , Sinais (Psicologia) , Potenciais Evocados/fisiologia , Adolescente , Adulto , Idoso , Mapeamento Encefálico , Transtornos Relacionados ao Uso de Cocaína/patologia , Transtornos Relacionados ao Uso de Cocaína/fisiopatologia , Transtornos Relacionados ao Uso de Cocaína/psicologia , Potenciais Evocados/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Adulto Jovem
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