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Pedro Ribeiro - One of the best experts on this subject based on the ideXlab platform.
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THE EFFECTS OF Bromazepam ON THE EARLY STAGE OF VISUAL INFORMATION PROCESSING (P100)
2016Co-Authors: Arq Neuropsiquiatr, Mauricio Cagy, Roberto Piedade, Heloisa Veiga, Isabel Sampaio, A Puga, Camila Ferreira, Pedro RibeiroAbstract:ABSTRACT- The early stages of visual information processing, involving the detection and perception of sim-ple visual stimuli, have been demonstrated to be sensitive to psychotropic agents. The present study inves-tigated the effects of an acute dose of Bromazepam (3 mg), compared with placebo, on the P100 compo-nent of the visual evoked potential and reaction time. The sample, consisting of 14 healthy subjects (6 male and 8 female), was submitted to a visual discrimination task, which employed the “oddball ” paradigm. Re-sults suggest that Bromazepam (3 mg) impairs the initial stage of visual information processing, as observed by an increase in P100 latency. KEY WORDS: Bromazepam, visual evoked potential, P100. Efeitos do Bromazepam no estágio inicial do processamento de informação visual (P100) RESUMO- Os estágios iniciais do processamento da informação visual, envolvendo a percepção e detecção de um estímulo visual simples, tem demonstrado serem sensíveis a agentes psicotrópicos. O presente estudo investigou os efeitos de uma dose aguda de Bromazepam (3 mg), comparado com placebo, no componente P100 do potencial evocado visual e no tempo de reação. A mostra consistiu de 14 sujeitos sadios (6 homens e 8 mulheres), submetidos a uma tarefa de discriminação visual, a qual empregou o paradigma “oddball”. Os resultados sugerem que o Bromazepam (3 mg) prejudica o estágio inicial do processamento da informa
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Alpha power oscillation in the frontal cortex under Bromazepam and Modafinil effects
Arquivos de Neuro-Psiquiatria, 2015Co-Authors: Danielle Aprigio, Mauricio Cagy, Luis F. H. Basile, Pedro Ribeiro, Mariana Gongora, Juliana Bittencourt, Silmar Teixeira, Henning Budde, Washington Adolfo, Bruna VelasquesAbstract:Objective Our aim was to investigate and compare the neuromodulatory effects of Bromazepam (6 mg) and modafinil (200 mg) during a sensorimotor task analyzing the changes produced in the absolute alpha power.Method The sample was composed of 15 healthy individuals exposed to three experimental conditions: placebo, modafinil and Bromazepam. EEG data were recorded before, during and after the execution of the task. A three-way ANOVA was applied, in order to compare the absolute alpha power among the factors: Group (control, Bromazepam and modafinil) Condition (Pre and Post-drug ingestion) and Moment (pre and post-stimulus).Results Interaction was found between the group and condition factors for Fp1, F4 and F3. We observed a main effect of moment and condition for the Fp2, F8 and Fz electrodes.Conclusion We concluded that drugs may interfere in sensorimotor processes, such as in the performance of tasks carried out in an unpredictable scenario.
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Absolute Theta Power in the Frontal Cortex During a Visuomotor Task: The Effect of Bromazepam on Attention.
Clinical EEG and Neuroscience, 2014Co-Authors: Mariana Gongora, Mauricio Cagy, Bruna Velasques, Caroline Peressuti, Juliana Bittencourt, Silmar Teixeira, Oscar Arias-carrión, Pedro RibeiroAbstract:Bromazepam is a benzodiazepine, which has been widely employed in the treatment of anxiety. We investigated the electrophysiological changes in absolute theta power within the frontal cortex when individuals performed a visuomotor task under Bromazepam. The sample of 17 healthy individuals was randomized into 2 experimental conditions, under which Bromazepam 6 mg and placebo were administered on different days. All subjects were right -handed, with no mental or physical illness and were not using any psychoactive or psychotropic substance during the entire period of the study. We found an increase in reaction time under Bromazepam compared with placebo . With regard to the electrophysiological variable, we found a lower theta power value in the prefrontal cortex prior to task execution, compared with after. We therefore suggested that this could be an increase of neural activity in this region, because of the subjects' readiness to perform the task, that is, because of their higher alertness. The right lateral frontal region showed lower theta power under Bromazepam for pre- and post-finger movement. This could have occurred because of more effort to execute the task. In the left frontal region: premovement did not demonstrate any difference between conditions, possibly because the proposed task was simple to execute. In conclusion, theta power plays an important role in the analysis of visuomotor performance, assuming that Bromazepam causes impairment on sustained attention and sensory perception.
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Influence of Bromazepam on cortical interhemispheric coherence
Arquivos de Neuro-Psiquiatria, 2007Co-Authors: Isabel Sampaio, Mauricio Cagy, Roberto Piedade, Fernanda Puga, Heloisa Veiga, Pedro RibeiroAbstract:Benzodiazepines are among the most commonly prescribed medications due to their therapeutic efficacy in reducing anxiety and inducing sleep. Consequently, they have been widely employed in the pharmacological treatment of several disorders. Nevertheless, few studies have analyzed the effects of Bromazepam in electroencephalographic activity (EEG). The present study aimed at investigating the modulatory effects of this drug on brain dynamics. Specifically, the effects of Bromazepam (3mg) on EEG coherence were tested in a double-blind experiment. The sample, consisting of 10 healthy subjects (5 male and 5 female), was submitted to ten minutes of EEG recording. The electrophysiological measure (coherence) was analyzed across three experimental conditions: Bromazepam, placebo 1, and placebo 2. Results indicate that Bromazepam significantly increases cortical interhemispheric coherence.
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Efeitos neuromoduladores do Bromazepam quando indivíduos são expostos a uma tarefa de aprendizagem motora: eletrencefalografia quantitativa (EEGq)
Arquivos de Neuro-Psiquiatria, 2006Co-Authors: José Inácio Salles, Victor Hugo Bastos, Marlo Cunha, Dionis Machado, Mauricio Cagy, Vernon Furtado, Luis F. H. Basile, Roberto Piedade, Pedro RibeiroAbstract:The sedative effects of Bromazepam on cognitive and performance have been widely investigated. A number of different approaches have assessed the influence of Bromazepam when individuals are engaged to a motor task. In this context, the present study aimed to investigate electrophysiological changes when individuals were exposed to a typewriting task after taking 6 mg of Bromazepam. qEEG data were simultaneously recorded during the task. In particular, relative power in delta band (0.5-3.5 Hz) was analyzed. Time of execution and errors during the task were registered as behavioral variables. The experimental group, Bromazepam 6mg, showed a better motor performance and higher relative power than control individuals (placebo). These results suggest that the use of Bromazepam reduces anxiety levels as expected and thus, produces an increment in motor performance.
Roberto Piedade - One of the best experts on this subject based on the ideXlab platform.
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THE EFFECTS OF Bromazepam ON THE EARLY STAGE OF VISUAL INFORMATION PROCESSING (P100)
2016Co-Authors: Arq Neuropsiquiatr, Mauricio Cagy, Roberto Piedade, Heloisa Veiga, Isabel Sampaio, A Puga, Camila Ferreira, Pedro RibeiroAbstract:ABSTRACT- The early stages of visual information processing, involving the detection and perception of sim-ple visual stimuli, have been demonstrated to be sensitive to psychotropic agents. The present study inves-tigated the effects of an acute dose of Bromazepam (3 mg), compared with placebo, on the P100 compo-nent of the visual evoked potential and reaction time. The sample, consisting of 14 healthy subjects (6 male and 8 female), was submitted to a visual discrimination task, which employed the “oddball ” paradigm. Re-sults suggest that Bromazepam (3 mg) impairs the initial stage of visual information processing, as observed by an increase in P100 latency. KEY WORDS: Bromazepam, visual evoked potential, P100. Efeitos do Bromazepam no estágio inicial do processamento de informação visual (P100) RESUMO- Os estágios iniciais do processamento da informação visual, envolvendo a percepção e detecção de um estímulo visual simples, tem demonstrado serem sensíveis a agentes psicotrópicos. O presente estudo investigou os efeitos de uma dose aguda de Bromazepam (3 mg), comparado com placebo, no componente P100 do potencial evocado visual e no tempo de reação. A mostra consistiu de 14 sujeitos sadios (6 homens e 8 mulheres), submetidos a uma tarefa de discriminação visual, a qual empregou o paradigma “oddball”. Os resultados sugerem que o Bromazepam (3 mg) prejudica o estágio inicial do processamento da informa
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EFFECTS OF A COGNITIVE MODULATOR IN THE THETA AND ALPHA ASYMMETRY DURING A TYPEWRITING TASK
2016Co-Authors: Arq Neuropsiquiatr, Victor Hugo Bastos, Marlo Cunha, Dionis Machado, Mauricio Cagy, Sergio Machado, Luiz Cláudio Miana, Bruna Velasques, Luis F. Basile, Roberto PiedadeAbstract:Abstract – This study aimed to elucidate cortical mechanisms and to identify the areas where occur such mechanisms due to interaction between Bromazepam and motor learning. The sample was composed of 45 healthy subjects randomly distributed in 3 groups: placebo (n=15), Bromazepam 3 mg (n=15) or Bromazepam 6 mg (n=15). To perform the experimental task, subjects sat comfortably at a distance of approximately 20 cm from the typewriter. The typewriter keyboard was covered with a wooden box to avoid visual information about the hands ’ position. The typewriting task was performed concomitantly with EEG recording. ANOVA two-way results indicated a decreased asymmetry in sensorimotor areas in the experimental groups. Our interpretation is that moderate doses of Bromazepam may improve performance on tasks with predictable elements to promote stability of psychomotor functions, but may also impair performance on tasks executed in unpredictable environments. KEy wOrds: Bromazepam, motor learning, qEEG, asymmetry, sensorimotor integration. Efeitos de um modulador cognitivo na assimetria de teta e alfa durante uma tarefa de datilografia: uma perspectiva da integração sensório-motora Resumo – O objetivo do estudo foi elucidar mecanismos corticais e identificar as áreas onde estas ocorrem tais mecanismos devido à interação entre Bromazepam e aprendizagem motora. A amostra compreende
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Bromazepam impairs motor response: an ERSP study.
CNS & Neurological Disorders - Drug Targets, 2011Co-Authors: Julio Guilherme Silva, Mauricio Cagy, Luis F. H. Basile, Roberto Piedade, Bruna Velasques, Silmar Teixeira, Oscar Arias-carrión, Flávia Paes, Antonio Egidio Nardi, Sergio A.s. MachadoAbstract:This study aimed to investigate the acute modulatory effect of Bromazepam, a benzodiazepine derivative drug, on alpha and beta bands (8-35Hz) in primary motor areas (M1) through event-related spectral perturbation (ERSP). Ten healthy subjects were submitted to a cross-over double-blind design. Subjects performed a visuomotor task where they had to identify rapidly the ball launched horizontally and catch it quickly, while electroencephalographic activity was acquired. We found a statistically significant difference on the time windows of 2920 ms for 13Hz in the electrodes C3 and Cz, and on the time window of 2000 ms for 18Hz in the electrodes C3, when compared the Bromazepam and placebo conditions. We concluded that the acute effects of Bromazepam provoked changes in information process in the left M1 represented by electrode C3 in both 13 Hz and 18 Hz. Our paradigm is relevant for a better understanding of the brain dynamics due to the information related to Bromazepam effects on sensorimotor processes. We consider this report an invitation to conduct more studies in order to associate electro-cortical activity and psychometric tests.
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The effects of Bromazepam over the temporo-parietal areas during the performance of a visuomotor task: a qEEG study.
Neuroscience Letters, 2011Co-Authors: Fernanda Araújo, Marlo Cunha, Mauricio Cagy, Luis F. H. Basile, Sergio Machado, Bruna Velasques, Oscar Arias-carrión, Flávia Paes, Henning Budde, Roberto PiedadeAbstract:This study investigated the effects of Bromazepam on qEEG when 14 healthy subjects were asked to perform a visuomotor task (i.e., motor vehicle driving task). The subjects were exposed to two experimental conditions: the placebo (PL) and 6 mg of Bromazepam (Br 6 mg), following a randomized, double-blind design on different days. Specifically, we observe absolute power extracted from qEEG data for theta band. We expected to see a decrease in absolute theta power in the temporal and parietal areas due to the influence of Bromazepam for the experimental group when compared with the placebo group. We found a main effect for the condition factor for electrodes T3, T4, P3 and P4. We also observed a main effect for the period factor for electrodes P3 and P4. We observed that the ingestion of 6 mg of Bromazepam induces different patterns in theta power at the temporal and parietal sites. We concluded that 6 mg of Bromazepam was an important factor in the fluctuation of the activities in the temporal and parietal areas. We then hypothesize about the specific role of this drug during the execution of a visuomotor task and within the sensorimotor integration process.
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Responsiveness of sensorimotor cortex during pharmacological intervention with Bromazepam.
Neuroscience Letters, 2008Co-Authors: Marlo Cunha, Victor Hugo Bastos, Dionis Machado, Mauricio Cagy, Luis F. H. Basile, Sergio Machado, Bruna Velasques, Henning Budde, Cláudio Portela, Roberto PiedadeAbstract:The aim of this study was to investigate the influence of Bromazepam on EEG and the motor learning process when healthy subjects were submitted to a typewriting task. We investigated Bromazepam due to its abuse by various populations and its prevalent clinical use among older individuals which are more sensitive to the negative effects of long half-life benzodiazepines. A randomized double-blind design was used with subjects divided into three groups: placebo (n=13), Bromazepam 3mg (n=13) and Bromazepam 6 mg (n=13). EEG data comprising theta, alpha and beta bands was recorded before, during and after the motor task. Our results showed a lower relative power value in the theta band in the Br 6 mg group when compared with PL. We also observed a reduction in relative power in the beta band in the Br 3mg and Br 6 mg when compared with PL group. These findings suggest that Br can contribute to a reduced working memory load in areas related to attention processes. On the other hand, it produces a higher cortical activation in areas associated with sensory integration. Such areas are responsible for accomplishing the motor learning task. The results are an example of the usefulness of integrating electrophysiological data, sensorimotor activity and a pharmacological approach to aid in our understanding of cerebral changes produced by external agents.
Myriam C Salvadori - One of the best experts on this subject based on the ideXlab platform.
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determination of Bromazepam in human plasma by high performance liquid chromatography with electrospray ionization tandem mass spectrometric detection application to a bioequivalence study
Journal of Mass Spectrometry, 2004Co-Authors: Maristela H Andraus, Anthony Wong, Ovandir A Silva, Cicilia Y Wada, Odaly Toffleto, Cristina P Azevedo, Myriam C SalvadoriAbstract:A simple method using a one-step liquid–liquid extraction (LLE) followed by high-performance liquid chromatography (HPLC) with positive ion electrospray ionization tandem mass spectrometric (ESI-MS/MS) detection was developed for the determination of Bromazepam in human plasma, using lorazepam as internal standard. The acquisition was performed in the multiple reaction monitoring mode, monitoring the transitions: m/z 316 > 182 for Bromazepam and m/z 321 > 275 for lorazepam. The method was linear over the studied range (1–100 ng ml−1), with r2 > 0.98, and the run time was 2.5 min. The intra- and inter-assay precisions were 2.7–14.6 and 4.1–17.3%, respectively and the intra- and inter-assay accuracies were 87–111 and 75.8–109.5%, respectively. The mean recovery was 73.7%, ranging from 64.5 to 79.7%. The limit of quantification was 1 ng ml−1. At this concentration the mean intra- and inter-assay precisions were 14.6 and 7.1%, respectively, and the mean intra- and inter-assay accuracies were 102.5 and 104%, respectively. Bromazepam stability was evaluated and the results showed that the drug is stable in standard solution and in plasma samples under typical storage and processing conditions. The method was applied to a bioequivalence study in which 27 healthy adult volunteers (14 men) received single oral doses (6 mg) of reference and test Bromazepam formulations, in an open, two-period, randomized, crossover protocol. The 90% confidence interval of the individual ratios (test formulation/reference formulation) for Cmax (peak plasma concentration), AUC0–96 and AUC0–inf (area under the plasma concentration versus time curve from time zero to 96 h and to infinity, respectively) were within the range 80–125%, which supports the conclusion that the test formulation is bioequivalent to the reference formulation regarding the rate and extent of Bromazepam absorption. Copyright © 2004 John Wiley & Sons, Ltd.
Mauricio Cagy - One of the best experts on this subject based on the ideXlab platform.
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THE EFFECTS OF Bromazepam ON THE EARLY STAGE OF VISUAL INFORMATION PROCESSING (P100)
2016Co-Authors: Arq Neuropsiquiatr, Mauricio Cagy, Roberto Piedade, Heloisa Veiga, Isabel Sampaio, A Puga, Camila Ferreira, Pedro RibeiroAbstract:ABSTRACT- The early stages of visual information processing, involving the detection and perception of sim-ple visual stimuli, have been demonstrated to be sensitive to psychotropic agents. The present study inves-tigated the effects of an acute dose of Bromazepam (3 mg), compared with placebo, on the P100 compo-nent of the visual evoked potential and reaction time. The sample, consisting of 14 healthy subjects (6 male and 8 female), was submitted to a visual discrimination task, which employed the “oddball ” paradigm. Re-sults suggest that Bromazepam (3 mg) impairs the initial stage of visual information processing, as observed by an increase in P100 latency. KEY WORDS: Bromazepam, visual evoked potential, P100. Efeitos do Bromazepam no estágio inicial do processamento de informação visual (P100) RESUMO- Os estágios iniciais do processamento da informação visual, envolvendo a percepção e detecção de um estímulo visual simples, tem demonstrado serem sensíveis a agentes psicotrópicos. O presente estudo investigou os efeitos de uma dose aguda de Bromazepam (3 mg), comparado com placebo, no componente P100 do potencial evocado visual e no tempo de reação. A mostra consistiu de 14 sujeitos sadios (6 homens e 8 mulheres), submetidos a uma tarefa de discriminação visual, a qual empregou o paradigma “oddball”. Os resultados sugerem que o Bromazepam (3 mg) prejudica o estágio inicial do processamento da informa
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EFFECTS OF A COGNITIVE MODULATOR IN THE THETA AND ALPHA ASYMMETRY DURING A TYPEWRITING TASK
2016Co-Authors: Arq Neuropsiquiatr, Victor Hugo Bastos, Marlo Cunha, Dionis Machado, Mauricio Cagy, Sergio Machado, Luiz Cláudio Miana, Bruna Velasques, Luis F. Basile, Roberto PiedadeAbstract:Abstract – This study aimed to elucidate cortical mechanisms and to identify the areas where occur such mechanisms due to interaction between Bromazepam and motor learning. The sample was composed of 45 healthy subjects randomly distributed in 3 groups: placebo (n=15), Bromazepam 3 mg (n=15) or Bromazepam 6 mg (n=15). To perform the experimental task, subjects sat comfortably at a distance of approximately 20 cm from the typewriter. The typewriter keyboard was covered with a wooden box to avoid visual information about the hands ’ position. The typewriting task was performed concomitantly with EEG recording. ANOVA two-way results indicated a decreased asymmetry in sensorimotor areas in the experimental groups. Our interpretation is that moderate doses of Bromazepam may improve performance on tasks with predictable elements to promote stability of psychomotor functions, but may also impair performance on tasks executed in unpredictable environments. KEy wOrds: Bromazepam, motor learning, qEEG, asymmetry, sensorimotor integration. Efeitos de um modulador cognitivo na assimetria de teta e alfa durante uma tarefa de datilografia: uma perspectiva da integração sensório-motora Resumo – O objetivo do estudo foi elucidar mecanismos corticais e identificar as áreas onde estas ocorrem tais mecanismos devido à interação entre Bromazepam e aprendizagem motora. A amostra compreende
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Alpha power oscillation in the frontal cortex under Bromazepam and Modafinil effects
Arquivos de Neuro-Psiquiatria, 2015Co-Authors: Danielle Aprigio, Mauricio Cagy, Luis F. H. Basile, Pedro Ribeiro, Mariana Gongora, Juliana Bittencourt, Silmar Teixeira, Henning Budde, Washington Adolfo, Bruna VelasquesAbstract:Objective Our aim was to investigate and compare the neuromodulatory effects of Bromazepam (6 mg) and modafinil (200 mg) during a sensorimotor task analyzing the changes produced in the absolute alpha power.Method The sample was composed of 15 healthy individuals exposed to three experimental conditions: placebo, modafinil and Bromazepam. EEG data were recorded before, during and after the execution of the task. A three-way ANOVA was applied, in order to compare the absolute alpha power among the factors: Group (control, Bromazepam and modafinil) Condition (Pre and Post-drug ingestion) and Moment (pre and post-stimulus).Results Interaction was found between the group and condition factors for Fp1, F4 and F3. We observed a main effect of moment and condition for the Fp2, F8 and Fz electrodes.Conclusion We concluded that drugs may interfere in sensorimotor processes, such as in the performance of tasks carried out in an unpredictable scenario.
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Absolute Theta Power in the Frontal Cortex During a Visuomotor Task: The Effect of Bromazepam on Attention.
Clinical EEG and Neuroscience, 2014Co-Authors: Mariana Gongora, Mauricio Cagy, Bruna Velasques, Caroline Peressuti, Juliana Bittencourt, Silmar Teixeira, Oscar Arias-carrión, Pedro RibeiroAbstract:Bromazepam is a benzodiazepine, which has been widely employed in the treatment of anxiety. We investigated the electrophysiological changes in absolute theta power within the frontal cortex when individuals performed a visuomotor task under Bromazepam. The sample of 17 healthy individuals was randomized into 2 experimental conditions, under which Bromazepam 6 mg and placebo were administered on different days. All subjects were right -handed, with no mental or physical illness and were not using any psychoactive or psychotropic substance during the entire period of the study. We found an increase in reaction time under Bromazepam compared with placebo . With regard to the electrophysiological variable, we found a lower theta power value in the prefrontal cortex prior to task execution, compared with after. We therefore suggested that this could be an increase of neural activity in this region, because of the subjects' readiness to perform the task, that is, because of their higher alertness. The right lateral frontal region showed lower theta power under Bromazepam for pre- and post-finger movement. This could have occurred because of more effort to execute the task. In the left frontal region: premovement did not demonstrate any difference between conditions, possibly because the proposed task was simple to execute. In conclusion, theta power plays an important role in the analysis of visuomotor performance, assuming that Bromazepam causes impairment on sustained attention and sensory perception.
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Bromazepam impairs motor response: an ERSP study.
CNS & Neurological Disorders - Drug Targets, 2011Co-Authors: Julio Guilherme Silva, Mauricio Cagy, Luis F. H. Basile, Roberto Piedade, Bruna Velasques, Silmar Teixeira, Oscar Arias-carrión, Flávia Paes, Antonio Egidio Nardi, Sergio A.s. MachadoAbstract:This study aimed to investigate the acute modulatory effect of Bromazepam, a benzodiazepine derivative drug, on alpha and beta bands (8-35Hz) in primary motor areas (M1) through event-related spectral perturbation (ERSP). Ten healthy subjects were submitted to a cross-over double-blind design. Subjects performed a visuomotor task where they had to identify rapidly the ball launched horizontally and catch it quickly, while electroencephalographic activity was acquired. We found a statistically significant difference on the time windows of 2920 ms for 13Hz in the electrodes C3 and Cz, and on the time window of 2000 ms for 18Hz in the electrodes C3, when compared the Bromazepam and placebo conditions. We concluded that the acute effects of Bromazepam provoked changes in information process in the left M1 represented by electrode C3 in both 13 Hz and 18 Hz. Our paradigm is relevant for a better understanding of the brain dynamics due to the information related to Bromazepam effects on sensorimotor processes. We consider this report an invitation to conduct more studies in order to associate electro-cortical activity and psychometric tests.
Gabriel Parreiras Estolano Da Silveira - One of the best experts on this subject based on the ideXlab platform.
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on line solid phase extraction coupled with high performance liquid chromatography and tandem mass spectrometry spe hplc ms ms for quantification of Bromazepam in human plasma an automated method for bioequivalence studies
Therapeutic Drug Monitoring, 2005Co-Authors: Jose Carlos Saraiva Goncalves, Tânia Maria Monteiro, Claudia Silvana De Miranda Neves, Karla Regina Da Silva Gram, Nadia Maria Volpato, Vivian De Almeida Silva, Ricardo Caminha, Maria Do Rocio Bencke Goncalves, Fabio Monteiro Dos Santos, Gabriel Parreiras Estolano Da SilveiraAbstract:A validated method for on-line solid-phase extraction coupled with high-performance liquid chromatography tandem mass spectrometry (SPE-HPLC-MS-MS) is described for the quantification of Bromazepam in human plasma. The method involves a dilution of 300 muL of plasma with 100 muL of carbamazepine (2.5 ng/mL), used as internal standard, vortex-mixing, centrifugation, and injection of 100 muL of the supernate. The analytes were ionized using positive electrospray mass spectrometry then detected by multiple reaction monitoring (MRM). The m/z transitions 316-->182 (Bromazepam) and 237-->194 (carbamazepine) were used for quantification. The calibration curve was linear from 1 ng/mL (limit of quantification) to 200 ng/mL. The retention times of Bromazepam and carbamazepine were 2.6 and 3.2 minutes, respectively. The intraday and interday precisions were 3.43%-15.45% and 5.2%-17%, respectively. The intraday and interday accuracy was 94.00%-103.94%. This new automated method has been successfully applied in a bioequivalence study of 2 tablet formulations of 6 mg Bromazepam: Lexotan(R) from Produtos Roche Quimicos e Farmaceuticos SA, Rio de Janeiro, Brazil (reference) and test formulation from Laboratorios Biosintetica Ltda, Sao Paulo, Brazil. Because the 90% CI of geometric mean ratios between reference and test were completely included in the 80%-125% interval, the 2 formulations were considered bioequivalent. The comparison of different experimental conditions for establishing a dissolution profile in vitro along with our bioavailability data further allowed us to propose rationally based experimental conditions for a dissolution test of Bromazepam tablets, actually lacking a pharmacopeial monograph.
