MARTA IMAMURA
Projetos de Pesquisa
Unidades Organizacionais
Departamento de MedicinaLegal, Ética Médica e Medicina Social e do Trabalho, Faculdade de Medicina - Docente
Instituto de Ortopedia e Traumatologia, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/41 - Laboratório de Investigação Médica do Sistema Músculoesquelético, Hospital das Clínicas, Faculdade de Medicina
LIM/40 - Laboratório de Imunohematologia e Hematologia Forense, Hospital das Clínicas, Faculdade de Medicina
Instituto de Ortopedia e Traumatologia, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/41 - Laboratório de Investigação Médica do Sistema Músculoesquelético, Hospital das Clínicas, Faculdade de Medicina
LIM/40 - Laboratório de Imunohematologia e Hematologia Forense, Hospital das Clínicas, Faculdade de Medicina
14 resultados
Resultados de Busca
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- Increased motor cortex inhibition as a marker of compensation to chronic pain in knee osteoarthritis(2021) SIMIS, Marcel; IMAMURA, Marta; MELO, Paulo S. de; MARDUY, Anna; PACHECO-BARRIOS, Kevin; TEIXEIRA, Paulo E. P.; BATTISTELLA, Linamara; FREGNI, FelipeThis study aims to investigate the associative and multivariate relationship between different sociodemographic and clinical variables with cortical excitability as indexed by transcranial magnetic stimulation (TMS) markers in subjects with chronic pain caused by knee osteoarthritis (OA). This was a cross-sectional study. Sociodemographic and clinical data were extracted from 107 knee OA subjects. To identify associated factors, we performed independent univariate and multivariate regression models per TMS markers: motor threshold (MT), motor evoked potential (MEP), short intracortical inhibition (SICI), intracortical facilitation (ICF), and cortical silent period (CSP). In our multivariate models, the two markers of intracortical inhibition, SICI and CSP, had a similar signature. SICI was associated with age (beta: 0.01), WOMAC pain (beta: 0.023), OA severity (as indexed by Kellgren-Lawrence Classification) (beta: - 0.07), and anxiety (beta: - 0.015). Similarly, CSP was associated with age (beta: - 0.929), OA severity (beta: 6.755), and cognition (as indexed by the Montreal Cognitive Assessment) (beta: - 2.106). ICF and MT showed distinct signatures from SICI and CSP. ICF was associated with pain measured through the Visual Analogue Scale (beta: - 0.094) and WOMAC (beta: 0.062), and anxiety (beta: - 0.039). Likewise, MT was associated with WOMAC (beta: 1.029) and VAS (beta: - 2.003) pain scales, anxiety (beta: - 0.813), and age (beta: - 0.306). These associations showed the fundamental role of intracortical inhibition as a marker of adaptation to chronic pain. Subjects with higher intracortical inhibition (likely subjects with more compensation) are younger, have greater cartilage degeneration (as seen by radiographic severity), and have less pain in WOMAC scale. While it does seem that ICF and MT may indicate a more acute marker of adaptation, such as that higher ICF and MT in the motor cortex is associated with lesser pain and anxiety.
- Electroencephalography as a Biomarker for Functional Recovery in Spinal Cord Injury Patients(2021) SIMIS, Marcel; CAMSARI, Deniz Doruk; IMAMURA, Marta; FILIPPO, Thais Raquel Martins; SOUZA, Daniel Rubio De; BATTISTELLA, Linamara Rizzo; FREGNI, FelipeBackground Functional changes after spinal cord injury (SCI) are related to changes in cortical plasticity. These changes can be measured with electroencephalography (EEG) and has potential to be used as a clinical biomarker. Method In this longitudinal study participants underwent a total of 30 sessions of robotic-assisted gait training (RAGT) over a course of 6 weeks. The duration of each session was 30 min. Resting state EEG was recorded before and after 30-session rehabilitation therapy. To measure gait, we used the Walking Index for Spinal Cord Injury Scale, 10-Meter- Walking Test, Timed-Up-and-Go, and 6-Min-Walking Test. Balance was measured using Berg Balance Scale. Results Fifteen participants with incomplete SCI who had AIS C or D injuries based on American Spinal Cord Injury Association Impairment Scale classification were included in this study. Mean age was 35.7 years (range 17-51) and the mean time since injury was 17.08 (range 4-37) months. All participants showed clinical improvement with the rehabilitation program. EEG data revealed that high beta EEG activity in the central area had a negative correlation with gait (p = 0.049; beta coefficient: -0.351; and adj-R-2: 0.23) and balance (p = 0.043; beta coefficient: -0.158; and adj-R-2:0.24) measured at baseline, in a way that greater high beta EEG power was related to worse clinical function at baseline. Moreover, improvement in gait and balance had negative correlations with the change in alpha/theta ratio in the parietal area (Gait: p = 0.049; beta coefficient: -0.351; adj-R-2: 0.23; Balance: p = 0.043; beta coefficient: -0.158; and adj-R-2: 0.24). Conclusion In SCI, functional impairment and subsequent improvement following rehabilitation therapy with RAGT correlated with the change in cortical activity measured by EEG. Our results suggest that EEG alpha/theta ratio may be a potential surrogate marker of functional improvement during rehabilitation. Future studies are necessary to improve and validate these findings as a neurophysiological biomarker for SCI rehabilitation.
- Functional Changes in Cortical Activity of Patients Submitted to Knee Osteoarthritis Treatment An Exploratory Pilot Study(2022) IUAMOTO, Leandro Ryuchi; IMAMURA, Marta; SAMESHIMA, Koichi; MEYER, Alberto; SIMIS, Marcel; BATTISTELLA, Linamara Rizzo; FREGNI, FelipeIntroduction There is evidence that brain plasticity is the central mechanism involved in the functional recovery process of patients with knee osteoarthritis. Studies involving the analysis of central nervous system mechanisms of pain control and recovery could provide more data on future therapeutic approaches. Objective The aim of the study was to explore possible functional changes in cortical activity of patients submitted to knee osteoarthritis standardized pain treatment using electroencephalography. Methodology Ten patients with clinical and radiological diagnosis of painful knee unilateral or bilateral osteoarthritis were recruited to participate in clinical (Pain's Visual Analog Scale), radiological (Kellgren-Lawrence Scale), and neurophysiological (electroencephalography) assessments to evaluate cortical activity during cortical pain modulation activity. The clinical and neurophysiological analyses were performed before and after standardized pain treatment. Results Eight patients participated in this study. A significant improvement in pain perception and relative increase in interhemispheric connectivity after therapies was observed. In electroencephalography analysis, tests with real movement showed a relative increase in density directed at Graph's analysis. Conclusions Relative increase density directed measures at connectivity analysis in electroencephalography after pain treatment can be possible parameters to be explored in future research with a larger number of patients.
- EEG theta and beta bands as brain oscillations for different knee osteoarthritis phenotypes according to disease severity(2022) SIMIS, Marcel; IMAMURA, Marta; PACHECO-BARRIOS, Kevin; MARDUY, Anna; MELO, Paulo S. de; MENDES, Augusto J.; TEIXEIRA, Paulo E. P.; BATTISTELLA, Linamara; FREGNI, FelipeThis study aims to investigate the multivariate relationship between different sociodemographic, clinical, and neurophysiological variables with resting-state, high-definition, EEG spectral power in subjects with chronic knee osteoarthritis (OA) pain. This was a cross-sectional study. Sociodemographic and clinical data were collected from 66 knee OA subjects. To identify associated factors, we performed independent univariate and multivariate regression models by frequency bands (delta, theta, alpha, beta, low-beta, and high-beta) and by pre-defined regions (frontal, central, and parietal). From adjusted multivariate models, we found that: (1) increased frontocentral high-beta power and reduced central theta activity are positively correlated with pain intensity (beta = 0.012, 95% CI 0.004-0.020; and beta = - 0.008; 95% CI 0.014 to - 0.003; respectively); (2) delta and alpha oscillations have a direct relationship with higher cortical inhibition; (3) diffuse increased power at low frequencies (delta and theta) are associated with poor cognition, aging, and depressive symptoms; and (4) higher alpha and beta power over sensorimotor areas seem to be a maladaptive compensatory mechanism to poor motor function and severe joint degeneration. Subjects with higher pain intensity and higher OA severity (likely subjects with maladaptive compensatory mechanisms to severe OA) have higher frontocentral beta power and lower theta activity. On the other hand, subjects with less OA severity and less pain have higher theta oscillations power. These associations showed the potential role of brain oscillations as a marker of pain intensity and clinical phenotypes in chronic knee OA patients. Besides, they suggest a potential compensatory mechanism of these two brain oscillators according to OA severity.
- Robot-Assisted Therapy and Constraint-Induced Movement Therapy for Motor Recovery in Stroke: Results From a Randomized Clinical Trial(2021) TERRANOVA, Thais Tavares; SIMIS, Marcel; SANTOS, Artur Cesar Aquino; ALFIERI, Fabio Marcon; IMAMURA, Marta; FREGNI, Felipe; BATTISTELLA, Linamara RizzoBackground: Stroke is one of the leading causes of adult disability, and up to 80% of stroke survivors undergo upper extremity motor dysfunction. Constraint-Induced Movement Therapy (CIMT) and Robot-Assisted Therapy (RT) are used for upper limb stroke rehabilitation. Although CIMT and RT are different techniques, both are beneficial; however, their results must be compared. The objective is to establish the difference between RT and CIMT after a rehabilitation program for chronic stroke patients. Method: This is a randomized clinical trial, registered at ClinicalTrials.gov (ID number NCT02700061), in which patients with stroke received sessions of RT or CIMT protocol, combined with a conventional rehabilitation program for 12 weeks. The primary outcome was measured by Wolf Motor Function Test (WMFT) and Fugl-Meyer Assessment-Upper Limb (FMA-UL). Activities of daily living were also assessed. Results: Fifty one patients with mild to moderate upper limb impairment were enrolled in this trial, 25 women and 26 men, mean age of 60,02 years old (SD 14,48), with 6 to 36 months after stroke onset. Function significantly improved regardless of the treatment group. However, no statistical difference was found between both groups as p-values of the median change of function measured by WMFT and FMA were 0.293 and 0.187, respectively. Conclusion: This study showed that Robotic Therapy (RT) was not different from Constraint-Induced Movement Therapy (CIMT) regardless of the analyzed variables. There was an overall upper limb function, motor recovery, functionality, and activities of daily living improvement regardless of the interventions. At last, the combination of both techniques should be considered in future studies.
- Functional and Neural Correlates Associated with Conditioned Pain Modulation in Patients with Chronic Knee Osteoarthritis Pain: A Cross-Sectional Study(2023) SIMIS, Marcel; PACHECO-BARRIOS, Kevin; VASQUEZ-AVILA, Karen; REBELLO-SANCHEZ, Ingrid; PARENTE, Joao; CASTELO-BRANCO, Luis; MARDUY, Anna; MELO, Paulo S. de; IMAMURA, Marta; BATTISTELLA, Linamara; FREGNI, FelipeIn this study, we aimed to assess the factors that predict a dysfunctional conditioned pain modulation (CPM) in chronic knee OA. Methods: This is a cross-sectional analysis of patients with chronic knee OA from a prospective cohort study in Brazil (n = 85). We performed linear and logistic multivariate regression models using the purposeful selection approach to test the relationship between the CPM in both knees (average) as a dependent variable and demographics, clinical, and neurophysiological as independent variables. Results: A significant negative association between WOMAC pain scores and CPM (beta: 0.13) was found. This association was modified by the subjects' race, being stronger in the non-white subjects. In our logistic regression models, pain intensity indexed with the WOMAC pain scale remained a significant association with dichotomized CPM. Furthermore, a significant CPM association with balance, indexed with the Berg Balance score, was evidenced ( beta: 0.04). Neurophysiological variables showed a significant negative relationship with CPM, such as the relative power of delta oscillations in the frontal area ( beta: 3.11) and central area ( beta: 3.23). There was no significant relationship between CPM and the following domains: cognitive, emotion, sleep, opioid receptor polymorphisms, and intrinsic variables of OA disease. There was no association of CPM with TMS-indexed inhibitory markers. Conclusions: These results may indicate that less function of the pain descending inhibitory system in patients with OA is correlated with higher activity-related pain (WOMAC), less balance, and cortical plasticity especially with increased low-frequency (delta) brain oscillations. These associations seem modified by race.
- Association of Mu opioid receptor (A118G) and BDNF (G196A) polymorphisms with rehabilitation-induced cortical inhibition and analgesic response in chronic osteoarthritis pain(2023) GONCALVES, Fernanda de Toledo; PACHECO-BARRIOS, Kevin; REBELLO-SANCHEZ, Ingrid; CASTELO-BRANCO, Luis; MELO, Paulo S. de; PARENTE, Joao; CARDENAS-ROJAS, Alejandra; FIRIGATO, Isabela; PESSOTTO, Anne Victorio; IMAMURA, Marta; SIMIS, Marcel; BATTISTELLA, Linamara; FREGNI, FelipeBackground/objective: Chronic pain due to osteoarthritis (OA) is a prevalent cause of global dis-ability. New biomarkers are needed to improve treatment allocation, and genetic polymorphisms are promising candidates. Method: We aimed to assess the association of OPRM1 (A118G and C17T) and brain-derived neurotrophic factor (BDNF [G196A]) polymorphisms with pain-related outcomes and motor cortex excitability metrics (measured by transcranial magnetic stimulation) in 113 knee OA patients with chronic pain. We performed adjusted multivariate regression analy-ses to compare carriers versus non-carriers in terms of clinical and neurophysiological character-istics at baseline, and treatment response (pain reduction and increased cortical inhibitory tonus) after rehabilitation. Results: Compared to non-carriers, participants with polymorphisms on both OPRM1 (A118G) and BDNF (G196A) genes were less likely to improve pain after rehabili-tation (85 and 72% fewer odds of improvement, respectively). Likewise, both carriers of OPRM1 polymorphisms (A118G and C17T) were also less likely to improve cortical inhibition (short intra-cortical inhibition [SICI], and intracortical facilitation [ICF], respectively). While pain and corti-cal inhibition improvement did not correlate in the total sample, the presence of OPRM1 (A118G) and BDNF (G196A) polymorphisms moderated this relationship. Conclusions: These results underscore the promising role of combining genetic and neurophysiological markers to endotype the treatment response in this population. (c) 2022 The Authors.
- Neurophysiological biomarkers of motor improvement from Constraint-Induced Movement Therapy and Robot-Assisted Therapy in participants with stroke(2023) SIMIS, Marcel; THIBAUT, Aurore; IMAMURA, Marta; BATTISTELLA, Linamara Rizzo; FREGNI, FelipeBackgroundThe mechanism of stroke recovery is related to the reorganization of cerebral activity that can be enhanced by rehabilitation therapy. Two well established treatments are Robot-Assisted Therapy (RT) and Constraint-Induced Movement Therapy (CIMT), however, it is unknown whether there is a difference in the neuroplastic changes induced by these therapies, and if the modifications are related to motor improvement. Therefore, this study aims to identify neurophysiological biomarkers related to motor improvement of participants with chronic stroke that received RT or CIMT, and to test whether there is a difference in neuronal changes induced by these two therapies.MethodsThis study included participants with chronic stroke that took part in a pilot experiment to compare CIMT vs. RT. Neurophysiological evaluations were performed with electroencephalography (EEG) and transcranial magnetic stimulation (TMS), pre and post rehabilitation therapy. Motor function was measured by the Wolf Motor Function Test (WMFT) and Fugl-Meyer Assessment Upper Limb (FMA-UL).ResultsTwenty-seven participants with chronic stroke completed the present study [mean age of 58.8 years (SD +/- 13.6), mean time since stroke of 18.2 months (SD +/- 9.6)]. We found that changes in motor threshold (MT) and motor evoked potential (MEP) in the lesioned hemisphere have a positive and negative correlation with WMFT improvement, respectively. The absolute change in alpha peak in the unlesioned hemisphere and the absolute change of the alpha ratio (unlesioned/lesioned hemisphere) is negatively correlated with WMFT improvement. The decrease of EEG power ratio (increase in the lesioned hemisphere and decrease in the unlesioned hemisphere) for high alpha bandwidths is correlated with better improvement in WMFT. The variable ""type of treatment (RT or CIMT)"" was not significant in the models.ConclusionOur results suggest that distinct treatments (RT and CIMT) have similar neuroplastic mechanisms of recovery. Moreover, motor improvements in participants with chronic stroke are related to decreases of cortical excitability in the lesioned hemisphere measured with TMS. Furthermore, the balance of both EEG power and EEG alpha peak frequency in the lesioned hemisphere is related to motor improvement.
- Neurophysiologic predictors of motor function in stroke(2016) SIMIS, Marcel; DORUK, Deniz; IMAMURA, Marta; ANGHINAH, Renato; MORALES-QUEZADA, Leon; FREGNI, Felipe; BATTISTELLA, Linamara RizzoPurpose: Understanding the neural mechanisms of stroke recovery is of paramount importance for neurorehabilitation. Methods: For this purpose, we analyzed several TMS and EEG variables and their association with motor recovery. Thirty-five subjects with chronic stroke were recruited. The neurophysiological examination included assessments by transcranial magnetic stimulation (TMS), intra-and inter-hemispheric EEG coherence in different frequency bands (e.g.alpha(8-13 Hz)) as determined by quantitative electroencephalography (qEEG). Motor function was measured by Fugl-Meyer (FM). Multiple univariate and multivariate linear regression analyses were performed to identify the predictors for FM. Results: Multivariate analyses, showed a significant interaction effect of motor threshold (MT) in the lesioned hemisphere and beta coherence in the unlesioned hemisphere. This interaction suggests that higher beta activity in the unlesioned hemisphere strengthens the negative association between MT and FM scores. Conclusions: Our results suggest that MT in the lesioned hemisphere is the strongest predictors of motor recovery after stroke. Moreover, cortical activity in the unlesioned hemisphere measured by qEEG provides additional information, specifying the association between MT and FM scores. Therefore, complementary application of EEG and TMS can help constitute a better model of the lesioned and the unlesioned hemispheres that supports the importance of bihemispheric activity in recovery.
- Deficit of Inhibition as a Marker of Neuroplasticity (DEFINE Study) in Rehabilitation: A Longitudinal Cohort Study Protocol(2021) SIMIS, Marcel; IMAMURA, Marta; MELO, Paulo Sampaio de; MARDUY, Anna; BATTISTELLA, Linamara; FREGNI, FelipeBackground: Brain plasticity is an intrinsic property of the nervous system, which is modified during its lifetime. This is one mechanism of recuperation after injuries with an important role in rehabilitation. Evidence suggests that injuries in the nervous system disturb the stability between inhibition and excitability essential for the recuperation process of neuroplasticity. However, the mechanisms involved in this balance are not completely understood and, besides the advancement in the field, the knowledge has had a low impact on the rehabilitation practice. Therefore, the understanding of the relationship between biomarkers and functional disability may help to optimize and individualize treatments and build consistent studies in the future. Methods: This cohort study, the deficit of inhibition as a marker of neuroplasticity study, will follow four groups (stroke, spinal cord injury, limb amputation, and osteoarthritis) to understand the neuroplasticity mechanisms involved in motor rehabilitation. We will recruit 500 subjects (including 100 age- and sex-matched controls). A battery of neurophysiological assessments, transcranial magnetic stimulation, electroencephalography, functional near-infrared spectroscopy, and magnetic resonance imaging, is going to be used to assess plasticity on the motor cortex before and after rehabilitation. One of the main hypotheses in this cohort is that the level of intracortical inhibition is related to functional deficits. We expect to develop a better understanding of the neuroplasticity mechanisms involved in the rehabilitation, and we expect to build neurophysiological ""transdiagnostic"" biomarkers, especially the markers of inhibition, which will have great relevance in the scientific and therapeutic improvement in rehabilitation. The relationship between neurophysiological and clinical outcomes will be analyzed using linear and logistic regression models. Discussion: By evaluating the reliability of electroencephalography, functional near-infrared spectroscopy, transcranial magnetic stimulation, and magnetic resonance imaging measures as possible biomarkers for neurologic rehabilitation in different neurologic disorders, this study will aid in the understanding of brain plasticity mechanisms in rehabilitation, allowing more effective approaches and screening methods to take place.