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
7 resultados
Resultados de Busca
Agora exibindo 1 - 7 de 7
- 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.
- 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.
- 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.
- 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.
- Factors associated with pain pressure threshold in both local and remote sites in knee osteoarthritis(2024) IMAMURA, Marta; REBELLO-SANCHEZ, Ingrid; PARENTE, Joao; MARDUY, Anna; VASQUEZ-AVILA, Karen; PACHECO-BARRIOS, Kevin; CASTELO-BRANCO, Luis; SIMIS, Marcel; BATTISTELLA, Linamara; FREGNI, FelipeBackground: Knee osteoarthritis (KOA) is a prevalent condition, and its most frequent symptom is pain that often leads to disability. Pain sensitization is a core feature of KOA, and it can be measured through quantitative sensory testing protocols such as pain pressure threshold (PPT). However, there is a lack of understanding about the factors that may influence changes in PPTs in the KOA population.Objective: To explore the clinical and functional factors associated with PPTs in a sample of people with chronic KOA pain and to compare models of local (knees) and remote (thenar regions) sites.Design: Cross-sectional analysis of a prospective cohort.Setting: Primary care in public institution.Participants: 113 adults with KOA.Intervention: N/A.Main Outcome MeasuresMultivariable regression analyses evaluating demographic, clinical, and functional variables that could be associated with local and remote PPTs (main outcomes) were performed.Results: Both thenar region (adjusted-R-2: 0.29) and knee (adjusted-R-2: 0.45) models had the same significant negative association with being a female, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain levels (thenar: beta: -0.15, p = .002; knee: beta: -0.2, p < .001), and the 10-Meter Walking Test (thenar: beta: -0.05, p = .038; knee: beta: -0.08, p = .004). A small significant positive association with depressive symptoms was identified in both models, which acted as a confounder for WOMAC pain and was likely affected by unmeasured confounders.Conclusions: PPTs in KOA pain are associated with functional outcomes such as the 10-Meter Walking Test and activity-related pain intensity; thus more disability is associated with smaller pain thresholds. Similarity between models may suggest central sensitization.
- OPRM1 and BDNF polymorphisms associated with a compensatory neurophysiologic signature in knee osteoarthritis patients(2023) GONCALVES, Fernanda de Toledo; MARQUES, Lucas Murrins; PESSOTTO, Anne Victorio; BARBOSA, Sara Pinto; IMAMURA, Marta; SIMIS, Marcel; FREGNI, Felipe; BATTISTELLA, LinamaraObjective: The present study investigated the relationship between three genetic polymor-phisms of OPRM1 (rs1799971 -A118G and rs1799972 -C17T) and BDNF (rs6265 -C196T) and EEG-measured brain oscillations in Knee Osteoarthritis (KOA) patients.Materials and Methods: We performed a cross-sectional analysis of a cohort study (DEFINE cohort), KOA arm, with 66 patients, considering demographic (age, sex, and education), clinical (pain intensity and duration), OPRM1 (rs1799971 -A118G and rs1799972 -C17T) and BDNF (rs6265 -C196T) genotypes, and electrophysiological measures. Brain oscillations relative power from Delta, Theta, Alpha, Low Alpha, High Alpha, Beta, Low Beta and High Beta oscillations were measured during resting state EEG. Multivariate regression models were used to explore the main brain oscillation predictors of the three genetic polymorphisms.Results: Our findings demonstrate that Theta and Low Beta oscillations are associated with the variant allele of OPRM1-rs1799971 (A118G) on left frontal and left central regions, respectively, while Alpha brain oscillation is associated with variant genotypes (CT/TT) of BDNF-rs6265 on frontal (decrease of oscillation power) and left central (increase of oscillation power) regions. No significant model was found for OPRM1-rs1799972 (C17T) in addition to the inclusion of pain intensity as a significant predictor of this last model.Conclusion: One potential interpretation for these findings is that polymorphisms of OPRM1 that is involved with endogenous pain control lead to increased compensatory oscillatory mechanisms, characterized by increased theta oscillations. Along the same line, polymorphisms of the BDNF lead to decreased alpha oscillations in the frontal area, likely also reflecting the disruption of resting states to also compensate for the increased injury associated with knee OA. It is possible that these polymorphisms require additional brain adaption to the knee OA related injury.(c) 2023 Published by Elsevier Masson SAS.