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1.
J Headache Pain ; 25(1): 154, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39294590

RESUMO

BACKGROUND: The pathophysiology of migraine remains poorly understood, yet a growing number of studies have shown structural connectivity disruptions across large-scale brain networks. Although both structural and functional changes have been found in the cerebellum of migraine patients, the cerebellum has barely been assessed in previous structural connectivity studies of migraine. Our objective is to investigate the structural connectivity of the entire brain, including the cerebellum, in individuals diagnosed with episodic migraine without aura during the interictal phase, compared with healthy controls. METHODS: To that end, 14 migraine patients and 15 healthy controls were recruited (all female), and diffusion-weighted and T1-weighted MRI data were acquired. The structural connectome was estimated for each participant based on two different whole-brain parcellations, including cortical and subcortical regions as well as the cerebellum. The structural connectivity patterns, as well as global and local graph theory metrics, were compared between patients and controls, for each of the two parcellations, using network-based statistics and a generalized linear model (GLM), respectively. We also compared the number of connectome streamlines within specific white matter tracts using a GLM. RESULTS: We found increased structural connectivity in migraine patients relative to healthy controls with a distinct involvement of cerebellar regions, using both parcellations. Specifically, the node degree of the posterior lobe of the cerebellum was greater in patients than in controls and patients presented a higher number of streamlines within the anterior limb of the internal capsule. Moreover, the connectomes of patients exhibited greater global efficiency and shorter characteristic path length, which correlated with the age onset of migraine. CONCLUSIONS: A distinctive pattern of heightened structural connectivity and enhanced global efficiency in migraine patients compared to controls was identified, which distinctively involves the cerebellum. These findings provide evidence for increased integration within structural brain networks in migraine and underscore the significance of the cerebellum in migraine pathophysiology.


Assuntos
Cerebelo , Conectoma , Imageamento por Ressonância Magnética , Transtornos de Enxaqueca , Humanos , Feminino , Adulto , Cerebelo/diagnóstico por imagem , Cerebelo/fisiopatologia , Cerebelo/patologia , Transtornos de Enxaqueca/diagnóstico por imagem , Transtornos de Enxaqueca/fisiopatologia , Transtornos de Enxaqueca/patologia , Adulto Jovem , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Masculino , Pessoa de Meia-Idade
3.
Int J Nanomedicine ; 19: 9091-9107, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39258003

RESUMO

Purpose: Castration Resistant Prostate Cancer (CRPC) is characterized by poor prognosis and limited therapeutic options. AgNPs functionalized with glucose (G-AgNPs) were observed cytotoxic to CRPC cell lines (PC-3 and Du-145) and not LNCaP. This study aims to evaluate AgNPs and G-AgNPs' uptake mechanisms in these cells and understand their role in the selective effect against CRPC cells. Methods: Uptake of AgNPs and G-AgNPs was assessed through transmission electron microscopy (TEM). A microRNA (miRNAs) analysis approach was used to uncover the main molecular differences responsible for the endocytic mechanisms' regulation. Caveolin (Cav) 1 and 2 mRNA and protein levels were assessed in the three cell lines. Caveolae-dependent endocytosis was inhibited with genistein or siCav1- and siCav2- in PC-3 and Du-145 and resazurin assay was used to evaluate viability after AgNPs and G-AgNPs administration. Caveolae-dependent endocytosis was induced with Cav1+ and Cav2+ plasmids in LNCaP, resazurin assay was used to evaluate viability after AgNPs and G-AgNPs administration and TEM to assess their location. Results: AgNPs and G-AgNPs were not uptaked by LNCaP. miRNA analysis revealed 37 upregulated and 90 downregulated miRNAs. Functional enrichment analysis of miRNAs' targets resulted in enrichment of terms related to endocytosis and caveolae. We observed that Cav1 and Cav2 are not expressed in LNCaP. Inhibiting caveolae-dependent endocytosis in Du-145 and PC-3 led to a significative reduction of cytotoxic capacity of AgNPs and G-AgNPs and induction of caveolae-dependent endocytosis in LNCaP lead to a significative increase as well as their uptake by cells. Conclusion: This study shows the potential of these AgNPs as a new therapeutic approach directed to CRPC patients, uncovers caveolae-dependent endocytosis as the uptake mechanism of these AgNPs and highlights deregulation of Cav1 and Cav2 expression as a key difference in hormone sensitive and resistant PCa cells which may be responsible for drug resistance.


Assuntos
Cavéolas , Caveolina 1 , Endocitose , Nanopartículas Metálicas , MicroRNAs , Neoplasias de Próstata Resistentes à Castração , Prata , Masculino , Humanos , Endocitose/efeitos dos fármacos , Endocitose/fisiologia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Cavéolas/metabolismo , Cavéolas/efeitos dos fármacos , Prata/química , Prata/farmacologia , Prata/farmacocinética , Caveolina 1/metabolismo , Caveolina 1/genética , Nanopartículas Metálicas/química , Linhagem Celular Tumoral , MicroRNAs/metabolismo , MicroRNAs/genética , Sobrevivência Celular/efeitos dos fármacos , Caveolina 2/metabolismo , Caveolina 2/genética , Antineoplásicos/farmacologia , Células PC-3
4.
Behav Sci (Basel) ; 14(7)2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-39062348

RESUMO

The importance of assessing psychopathic traits in juveniles who have committed sexual offenses has been established in individuals who demonstrate a particularly severe and violent pattern of behavior. Additionally, the assessment of these traits in other juveniles might be relevant considering that higher levels of these traits represent an increased probability of the juvenile committing offenses. This study is a systematic review of the literature about the presence of callous-unemotional (CU) traits in juveniles who have committed sexual and non-sexual offenses, in order to ascertain eventual differences between these groups regarding the presence of CU traits. Studies were obtained from multiple databases, with predefined exclusion and inclusion criteria, according to PRISMA-P guidelines. A total of 18 studies were reviewed and included in the final analysis. The 18 studies used measures of CU traits and reported descriptive categories of CU traits in juveniles who have committed general offenses or juveniles who have committed sexual offenses. Meta-analytic procedures such as pooled means, pooled variances, and pooled standard deviations are presented in this study. The main conclusion obtained is that juveniles who have committed general offenses present higher levels of CU traits compared to juveniles who have committed sexual offenses. Although the review highlights limitations in the literature, the identification of these characteristics in different types of juveniles who have committed offenses is important to shed light on the phenomenon and develop interventions better suited to their characteristics. Recommendations for future research are also presented.

5.
Behav Sci (Basel) ; 14(7)2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39062432

RESUMO

In recent decades, many researchers have focused on the development of Conduct Problems from childhood to adolescence. Understanding behavior problems also requires an understanding of well-regulated characteristics. Focusing our assessment on strengths makes it possible, on the one hand, to help children or adolescents with deficits in important areas (e.g., socio-emotional deficits) to develop emotional regulation skills and adapt their responses to different contexts. This study aims to understand the role of self-competence, self-regulation, empathy, and responsibility (strength variables) in the relationship between Callous Unemotional characteristics and Conduct Problems, with a sample of 236 children aged between 3 and 10 years (M = 7.51, SD = 1.63), through mediation analysis. In general, our findings suggest that self-regulation significantly explains the relationship between the callous dimension of the Inventory of Callous-Unemotional Traits and Conduct Problems, pointing out that this strength variable seems to act as a protective factor against the development of behavior problems. No other mediation effects were found, and these results are considered in light of some limitations.

7.
Magn Reson Med ; 92(2): 836-852, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38502108

RESUMO

PURPOSE: Arterial spin labeling (ASL) is a widely used contrast-free MRI method for assessing cerebral blood flow (CBF). Despite the generally adopted ASL acquisition guidelines, there is still wide variability in ASL analysis. We explored this variability through the ISMRM-OSIPI ASL-MRI Challenge, aiming to establish best practices for more reproducible ASL analysis. METHODS: Eight teams analyzed the challenge data, which included a high-resolution T1-weighted anatomical image and 10 pseudo-continuous ASL datasets simulated using a digital reference object to generate ground-truth CBF values in normal and pathological states. We compared the accuracy of CBF quantification from each team's analysis to the ground truth across all voxels and within predefined brain regions. Reproducibility of CBF across analysis pipelines was assessed using the intra-class correlation coefficient (ICC), limits of agreement (LOA), and replicability of generating similar CBF estimates from different processing approaches. RESULTS: Absolute errors in CBF estimates compared to ground-truth synthetic data ranged from 18.36 to 48.12 mL/100 g/min. Realistic motion incorporated into three datasets produced the largest absolute error and variability between teams, with the least agreement (ICC and LOA) with ground-truth results. Fifty percent of the submissions were replicated, and one produced three times larger CBF errors (46.59 mL/100 g/min) compared to submitted results. CONCLUSIONS: Variability in CBF measurements, influenced by differences in image processing, especially to compensate for motion, highlights the significance of standardizing ASL analysis workflows. We provide a recommendation for ASL processing based on top-performing approaches as a step toward ASL standardization.


Assuntos
Encéfalo , Circulação Cerebrovascular , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Marcadores de Spin , Humanos , Circulação Cerebrovascular/fisiologia , Reprodutibilidade dos Testes , Encéfalo/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Imagem de Perfusão/métodos , Masculino , Feminino , Adulto , Algoritmos
8.
J Rehabil Med ; 56: jrm18253, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38450442

RESUMO

OBJECTIVE: To examine the clinical effects of combining motor imagery-based neurofeedback training with bilateral repetitive transcranial magnetic stimulation for upper limb motor function in subacute and chronic stroke. DESIGN: Clinical trial following an AB/BA crossover design with counterbalanced assignment. SUBJECTS: Twenty individuals with subacute (n = 4) or chronic stroke (n = 16). METHODS: Ten consecutive sessions of bilateral repetitive transcranial magnetic stimulation alone (therapy A) were compared vs a combination of10 consecutive sessions of bilateral repetitive transcranial magnetic stimulation with 12 non-consecutive sessions of motor imagery-based neurofeedback training (therapy B). Patients received both therapies (1-month washout period), in sequence AB or BA. Participants were assessed before and after each therapy and at 15-days follow-up, using the Fugl-Meyer Assessment-upper limb, hand-grip strength, and the Nottingham Sensory Assessment as primary outcome measures. RESULTS: Both therapies resulted in improved functionality and sensory function. Therapy B consistently exhibited superior effects compared with therapy A, according to Fugl-Meyer Assessment and tactile and kinaesthetic sensory function across multiple time-points, irrespective of treatment sequence. No statistically significant differences between therapies were found for hand-grip strength. CONCLUSION: Following subacute and chronic stroke, integrating bilateral repetitive transcranial magnetic stimulation and motor imagery-based neurofeedback training has the potential to enhance functional performance compared with using bilateral repetitive transcranial magnetic stimulation alone in upper limb recovery.


Assuntos
Neurorretroalimentação , Acidente Vascular Cerebral , Humanos , Estudos Cross-Over , Força da Mão , Acidente Vascular Cerebral/complicações , Estimulação Magnética Transcraniana , Extremidade Superior
9.
MAGMA ; 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38393541

RESUMO

OBJECTIVE: Diffusional kurtosis imaging (DKI) extends diffusion tensor imaging (DTI), characterizing non-Gaussian diffusion effects but requires longer acquisition times. To ensure the robustness of DKI parameters, data acquisition ordering should be optimized allowing for scan interruptions or shortening. Three methodologies were used to examine how reduced diffusion MRI scans impact DKI histogram-metrics: 1) the electrostatic repulsion model (OptEEM); 2) spherical codes (OptSC); 3) random (RandomTRUNC). MATERIALS AND METHODS: Pre-acquired diffusion multi-shell data from 14 female healthy volunteers (29±5 years) were used to generate reordered data. For each strategy, subsets containing different amounts of the full dataset were generated. The subsampling effects were assessed on histogram-based DKI metrics from tract-based spatial statistics (TBSS) skeletonized maps. To evaluate each subsampling method on simulated data at different SNRs and the influence of subsampling on in vivo data, we used a 3-way and 2-way repeated measures ANOVA, respectively. RESULTS: Simulations showed that subsampling had different effects depending on DKI parameter, with fractional anisotropy the most stable (up to 5% error) and radial kurtosis the least stable (up to 26% error). RandomTRUNC performed the worst while the others showed comparable results. Furthermore, the impact of subsampling varied across distinct histogram characteristics, the peak value the least affected (OptEEM: up to 5% error; OptSC: up to 7% error) and peak height (OptEEM: up to 8% error; OptSC: up to 11% error) the most affected. CONCLUSION: The impact of truncation depends on specific histogram-based DKI metrics. The use of a strategy for optimizing the acquisition order is advisable to improve DKI robustness to exam interruptions.

10.
Aquichan (En linea) ; 24(1): e2414, 29 ene. 2024.
Artigo em Inglês, Português | LILACS, BDENF - Enfermagem, COLNAL | ID: biblio-1566158

RESUMO

Introducción: el estudio aporta evidencias científicas sin precedentes para la expansión de la alfabetización en salud como herramienta capaz de aumentar la seguridad del paciente a través de una comunicación eficaz entre los profesionales de la salud y sus pacientes, especialmente en atención primaria. Objetivo: mapear la evidencia sobre el impacto de la alfabetización en salud en la seguridad de la atención a pacientes adultos en atención primaria. Material y método: revisión exploratoria según el método del Instituto Joanna Briggs, en la que se contemplaron cuidados, técnicas, protocolos o métodos de alfabetización en salud utilizados para mejorar la atención primaria de salud. Se utilizaron las bases de datos Medline (PubMed), Web of Science, Scientific Electronic Library Online (SciELO), Virtual Health Library, Scopus, Cinahl y Google Scholar para la literatura gris. Se incluyeron los estudios originales disponibles en su totalidad, publicados hasta enero de 2023, en todos los idiomas que cubrían el tema. Dos pares seleccionaron por título y resumen, y tres pares leyeron los textos completos y extrajeron los datos de los artículos seleccionados, que se presentaron en flujogramas, tablas y narrativas descriptivas. Resultados: se encontraron 3749 estudios, de los que se seleccionaron 23. De ellos surgieron las siguientes categorías: "impacto de la alfabetización en salud sobre el compromiso y los resultados en salud de los usuarios de atención primaria"; "intervenciones que contribuyen a la alfabetización en salud en atención primaria" y "evaluación de las perspectivas de los usuarios y los profesionales sobre la alfabetización en salud". Conclusiones: las intervenciones de alfabetización en salud centradas en la atención primaria deben fomentarse en los servicios de salud para promover la atención, prevenir enfermedades e inspirar el proceso de transformación de la población, lo que repercute directamente en la seguridad de los pacientes.


Introdução: este estudo traz evidências científicas inéditas para a ampliação do letramento em saúde, como uma ferramenta capaz de aumentar a segurança do paciente através da comunicação eficaz entre os profissionais de saúde e seus pacientes, em especial nos cuidados primários em saúde. Objetivo: mapear evidências sobre o impacto do letramento em saúde na segurança do cuidado de pacientes adultos da atenção primária à saúde. Materiais e método: revisão de escopo de acordo com o método do Instituto Joanna Briggs, em que foram contemplados cuidados, técnicas, protocolos ou métodos de letramento em saúde utilizados para melhorar a assistência primária à saúde. Utilizaram-se as bases Medline (PubMed), Web of Science, Scientific Electronic Library Online (SciELO), Biblioteca Virtual em Saúde, Scopus, Cinahl e Google Acadêmico na literatura cinzenta. Foram incluídos estudos originais disponíveis na íntegra, publicados até janeiro de 2023, em todos os idiomas que englobassem a temática. Dois revisores realizaram a triagem por título e resumo, e três revisores leram os textos completos e extraíram dados dos artigos selecionados, sendo apresentados através de fluxo, tabela e narrativa descritiva. Resultados: foram encontrados 3749 estudos, dos quais 23 foram selecionados. Destes, surgiram as seguintes categorias: "impacto do letramento em saúde no engajamento e desfechos de saúde de usuários da atenção primária à saúde"; "intervenções que contribuem para o letramento em saúde na atenção primária à saúde" e "avaliação das perspectivas de usuários e profissionais quanto ao letramento em saúde". Conclusões: intervenções para o letramento em saúde com foco nos cuidados primários devem ser estimuladas dentro dos serviços de saúde a fim de promover o cuidado, prevenir agravos e inspirar o processo de transformação da população, impactando diretamente na segurança do paciente.


Introduction: This study provides unprecedented scientific evidence for the expansion of health literacy as a tool capable of increasing patient safety through effective communication between health care professionals and their patients, especially in primary health care. Objective: To map the evidence available regarding the impact of health literacy on care safety for adult patients in primary health care. Materials and methods: This is a scoping review in line with the Joanna Briggs Institute method, which covers care, techniques, protocols, or health literacy methods used to improve primary health care. The Medline (PubMed), Web of Science, Scientific Electronic Library Online (SciELO), Virtual Health Library, Scopus, Cinahl, and Google Scholar databases were used for the gray literature search. Original studies available in full and published until January 2023, in all languages covering the topic, were included. Two reviewers screened them by title and abstract, and three reviewers read the full texts and extracted data from the selected articles presented in flowcharts, tables, and descriptive narratives. Results: A total of 3749 studies were found, of which 23 were selected. From these, the following categories emerged: 'The impact of health literacy on the engagement and health outcomes of primary health care users;' 'Interventions that contribute to health literacy in primary health care;' and 'Evaluation of users' and professionals' perspectives on health literacy.' Conclusions: Health literacy interventions focused on primary care should be encouraged within health care services to promote care, prevent illnesses, and inspire the population's transformation process, with a direct impact on patient safety.


Assuntos
Atenção Primária à Saúde , Enfermagem , Assistência Centrada no Paciente , Letramento em Saúde , Segurança do Paciente
11.
Neurol Sci ; 45(3): 1201-1208, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37847419

RESUMO

OBJECTIVE: To investigate the neural correlates of working memory during a spontaneous migraine attack compared to the interictal phase, using functional magnetic resonance imaging (fMRI). BACKGROUND: Cognitive disturbances are commonly observed during migraine attacks, particularly in the headache phase. However, the neural basis of these changes remains unknown. METHODS: In a fMRI within-subject test-retest design study, eleven women (32 years of age, average) with episodic migraine were evaluated twice, first during a spontaneous migraine attack, and again in a pain-free period. Each session consisted in a cognitive assessment and fMRI while performing a working memory task (N-back). RESULTS: Cognitive test scores were lower during the ictal session than in the pain-free session. Regions typically associated with working memory were activated during the N-back task in both sessions. A voxel wise between session comparison showed significantly greater activation in the left frontal pole and orbitofrontal cortex during the attack relative to the interictal phase. CONCLUSION: Migraine patients exhibited greater activation of the left frontal pole and orbitofrontal cortex while executing a verbal working memory task during a spontaneous migraine attack when compared to the interictal state. Given the association of these regions with pain processing and inhibitory control, these findings suggest that patients recruit inhibitory areas to accomplish the cognitive task during migraine attacks, a neural signature of their cognitive difficulties.


Assuntos
Imageamento por Ressonância Magnética , Transtornos de Enxaqueca , Humanos , Feminino , Memória de Curto Prazo , Transtornos de Enxaqueca/diagnóstico por imagem , Cefaleia , Córtex Pré-Frontal
12.
Antioxidants (Basel) ; 12(12)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38136171

RESUMO

Nanomedicine's advent has promised to revolutionize different biomedical fields, including oncology. Silver Nanoparticles (AgNPs) showed promising results in different tumor models. Clear cell Renal Cell Carcinoma (ccRCC) is especially challenging due to its late diagnosis, poor prognosis and treatment resistance. Therefore, defining new therapeutic targets and regimens could improve patient management. This study intends to evaluate AgNPs' effect in ccRCC cells and explore their potential combinatory effect with Everolimus and Radiotherapy. AgNPs were synthesized, and their effect was evaluated regarding their entering pathway, cellular proliferation capacity, ROS production, mitochondrial membrane depolarization, cell cycle analysis and apoptosis assessment. AgNPs were combined with Everolimus or used to sensitize cells to radiotherapy. AgNPs are cytotoxic to 786-O cells, a ccRCC cell line, entering through endocytosis, increasing ROS, depolarizing mitochondrial membrane, and blocking the cell cycle, leading to a reduction of proliferation capacity and apoptosis. Combined with Everolimus, AgNPs reduce cell viability and inhibit proliferation capacity. Moreover, 786-O is intrinsically resistant to radiation, but after AgNPs' administration, radiation induces cytotoxicity through mitochondrial membrane depolarization and S phase blockage. These results demonstrate AgNPs' cytotoxic potential against ccRCC and seem promising regarding the combination with Everolimus and sensitization to radiotherapy, which can, in the future, benefit ccRCC patients' management.

13.
J Neural Eng ; 20(5)2023 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-37879343

RESUMO

Electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) are two commonly used non-invasive techniques for measuring brain activity in neuroscience and brain-computer interfaces (BCI).Objective. In this review, we focus on the use of EEG and fMRI in neurofeedback (NF) and discuss the challenges of combining the two modalities to improve understanding of brain activity and achieve more effective clinical outcomes. Advanced technologies have been developed to simultaneously record EEG and fMRI signals to provide a better understanding of the relationship between the two modalities. However, the complexity of brain processes and the heterogeneous nature of EEG and fMRI present challenges in extracting useful information from the combined data.Approach. We will survey existing EEG-fMRI combinations and recent studies that exploit EEG-fMRI in NF, highlighting the experimental and technical challenges.Main results. We made a classification of the different combination of EEG-fMRI for NF, we provide a review of multimodal analysis methods for EEG-fMRI features. We also survey the current state of research on EEG-fMRI in the different existing NF paradigms. Finally, we also identify some of the remaining challenges in this field.Significance. By exploring EEG-fMRI combinations in NF, we are advancing our knowledge of brain function and its applications in clinical settings. As such, this review serves as a valuable resource for researchers, clinicians, and engineers working in the field of neural engineering and rehabilitation, highlighting the promising future of EEG-fMRI-based NF.


Assuntos
Interfaces Cérebro-Computador , Neurorretroalimentação , Neurorretroalimentação/métodos , Imageamento por Ressonância Magnética/métodos , Eletroencefalografia/métodos , Encéfalo
14.
BMC Complement Med Ther ; 23(1): 374, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872494

RESUMO

BACKGROUND: Given the rising occurrence of antibiotic resistance due to the existence and ongoing development of resistant bacteria and phenotypes, the identification of new treatments and sources of antimicrobial agents is of utmost urgency. An important strategy for tackling bacterial resistance involves the utilization of drug combinations, and natural products derived from plants hold significant potential as a rich source of bioactive compounds that can act as effective adjuvants. This study, therefore, aimed to assess the antibacterial potential and the chemical composition of Miconia albicans, a Brazilian medicinal plant used to treat various diseases. METHODS: Ethanolic extracts from leaves and stems of M. albicans were obtained and subsequently partitioned to give the corresponding hexane, chloroform, ethyl acetate, and hydromethanolic phases. All extracts and phases had their chemical constitution investigated by HPLC-DAD-MS/MS and GC-MS and were assessed for their antibiofilm and antimicrobial efficacy against Staphylococcus aureus. Furthermore, their individual effects and synergistic potential in combination with antibiotics were examined against clinical strains of both S. aureus and Acinetobacter baumannii. In addition, 10 isolated compounds were obtained from the leaves phases and used for confirmation of the chemical profiles and for antibacterial assays. RESULTS: Based on the chemical profile analysis, 32 compounds were successfully or tentatively identified, including gallic and ellagic acid derivatives, flavonol glycosides, triterpenes and pheophorbides. Extracts and phases obtained from the medicinal plant M. albicans demonstrated synergistic effects when combined with the commercial antibiotics ampicillin and ciprofloxacin, against multi-drug resistant bacteria S. aureus and A. baumannii, restoring their antibacterial efficacy. Extracts and phases also exhibited antibiofilm property against S. aureus. Three key compounds commonly found in the samples, namely gallic acid, quercitrin, and corosolic acid, did not exhibit significant antibacterial activity when assessed individually or in combination with antibiotics against clinical bacterial strains. CONCLUSIONS: Our findings reveal that M. albicans exhibits remarkable adjuvant potential for enhancing the effectiveness of antimicrobial drugs against resistant bacteria.


Assuntos
Acinetobacter baumannii , Anti-Infecciosos , Melastomataceae , Plantas Medicinais , Staphylococcus aureus , Ciprofloxacina/farmacologia , Plantas Medicinais/química , Espectrometria de Massas em Tandem , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Ampicilina/farmacologia , Anti-Infecciosos/farmacologia , Bactérias
15.
PLoS One ; 18(9): e0291528, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37756271

RESUMO

Training motor imagery (MI) and motor observation (MO) tasks is being intensively exploited to promote brain plasticity in the context of post-stroke rehabilitation strategies. This may benefit from the use of closed-loop neurofeedback, embedded in brain-computer interfaces (BCI's) to provide an alternative non-muscular channel, which may be further augmented through embodied feedback delivered through virtual reality (VR). Here, we used functional magnetic resonance imaging (fMRI) in a group of healthy adults to map brain activation elicited by an ecologically-valid task based on a VR-BCI paradigm called NeuRow, whereby participants perform MI of rowing with the left or right arm (i.e., MI), while observing the corresponding movement of the virtual arm of an avatar (i.e., MO), on the same side, in a first-person perspective. We found that this MI-MO task elicited stronger brain activation when compared with a conventional MI-only task based on the Graz BCI paradigm, as well as to an overt motor execution task. It recruited large portions of the parietal and occipital cortices in addition to the somatomotor and premotor cortices, including the mirror neuron system (MNS), associated with action observation, as well as visual areas related with visual attention and motion processing. Overall, our findings suggest that the virtual representation of the arms in an ecologically-valid MI-MO task engage the brain beyond conventional MI tasks, which we propose could be explored for more effective neurorehabilitation protocols.


Assuntos
Interfaces Cérebro-Computador , Realidade Virtual , Adulto , Humanos , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Imagens, Psicoterapia
16.
Neuroimage ; 280: 120353, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37652114

RESUMO

The simultaneous acquisition of electroencephalography and functional magnetic resonance imaging (EEG-fMRI) allows the complementary study of the brain's electrophysiology and hemodynamics with high temporal and spatial resolution. One application with great potential is neurofeedback training of targeted brain activity, based on the real-time analysis of the EEG and/or fMRI signals. This depends on the ability to reduce in real time the severe artifacts affecting the EEG signal acquired with fMRI, mainly the gradient and pulse artifacts. A few methods have been proposed for this purpose, but they are either slow, hardware-dependent, publicly unavailable, or proprietary software. Here, we present a fully open-source and publicly available tool for real-time EEG artifact reduction in simultaneous EEG-fMRI recordings that is fast and applicable to any hardware. Our tool is integrated in the Python toolbox NeuXus for real-time EEG processing and adapts to a real-time scenario well-established artifact average subtraction methods combined with a long short-term memory network for R peak detection. We benchmarked NeuXus on three different datasets, in terms of artifact power reduction and background signal preservation in resting state, alpha-band power reactivity to eyes closure, and event-related desynchronization during motor imagery. We showed that NeuXus performed at least as well as the only available real-time tool for conventional hardware setups (BrainVision's RecView) and a well-established offline tool (EEGLAB's FMRIB plugin). We also demonstrated NeuXus' real-time ability by reporting execution times under 250 ms. In conclusion, we present and validate the first fully open-source and hardware-independent solution for real-time artifact reduction in simultaneous EEG-fMRI studies.


Assuntos
Imageamento por Ressonância Magnética , Neurorretroalimentação , Humanos , Artefatos , Eletroencefalografia , Benchmarking
17.
Brain Res ; 1818: 148513, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37499729

RESUMO

BACKGROUND: Previous functional magnetic resonance imaging studies have identified brain-connectivity alterations across multiple regions in people with migraine when compared to healthy controls. Few studies have focused on such changes throughout the different phases of the migraine cycle. We aimed to investigate functional connectivity during spontaneous occurring episodic migraine attacks, in comparison to interictal periods. METHODS: Eleven women with episodic migraine without aura underwent two sessions of resting-state fMRI, during and outside of a spontaneous migraine attack. Functional connectivity changes were assessed across canonical resting-state networks, identified by independent component analysis. Significantly altered connectivity was correlated with migraine attack symptoms. RESULTS: Decreased functional connectivity between subregions of the sensorimotor network (specifically, the primary somatosensory and motor cortices) and the posterior insula, bilaterally, was found during attacks. In both sessions, the functional connectivity between these regions was lower in patients who usually suffered longer attacks. DISCUSSION: The sensorimotor and insular regions are involved in nociceptive, autonomic, and somatosensory processing so the finding of reduced connectivity between these structures within a migraine attack is likely associated to the perception of pain and the heighten sensitivity to stimuli experienced in this disorder.


Assuntos
Epilepsia , Transtornos de Enxaqueca , Humanos , Feminino , Imageamento por Ressonância Magnética/métodos , Transtornos de Enxaqueca/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos
18.
Magn Reson Imaging ; 102: 141-150, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37343905

RESUMO

PURPOSE: The consensus for the clinical implementation of arterial spin labeling (ASL) perfusion imaging recommends a segmented 3D Gradient and Spin-Echo (GRASE) readout for optimal signal-to-noise-ratio (SNR). The correction of the associated susceptibility-induced geometric distortions has been shown to improve diagnostic precision, but its impact on ASL data has not been systematically assessed and it is not consistently part of pre-processing pipelines. Here, we investigate the effects of susceptibility-induced distortion correction on perfusion imaging by pseudo-continuous ASL (pCASL) with a segmented 3D GRASE readout. METHODS: Data acquired from 28 women using pCASL with 3D GRASE at 3T was analyzed using three pre-processing options: without distortion correction, with distortion correction, and with spatial smoothing (without distortion correction) matched to control for blurring effects induced by distortion correction. Maps of temporal SNR (tSNR) and relative perfusion were analyzed in eight regions-of-interest (ROIs) across the brain. RESULTS: Distortion correction significantly affected tSNR and relative perfusion across the brain. Increases in tSNR were like those produced by matched spatial smoothing in most ROIs, indicating that they were likely due to blurring effects. However, that was not the case in the frontal and temporal lobes, where we also found increased relative perfusion with distortion correction even compared with matched spatial smoothing. These effects were found in both controls and patients, with no interactions with the participant group. CONCLUSION: Correction of susceptibility-induced distortions significantly impacts ASL perfusion imaging using a segmented 3D GRASE readout, and this step should therefore be considered in ASL pre-processing pipelines. This is of special importance in clinical studies, reporting perfusion across ROIs defined on relatively undistorted images and when conducting group analyses requiring the alignment of images across different subjects.


Assuntos
Encéfalo , Imageamento Tridimensional , Humanos , Feminino , Imageamento Tridimensional/métodos , Encéfalo/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Marcadores de Spin , Imagem de Perfusão , Circulação Cerebrovascular , Imageamento por Ressonância Magnética/métodos
19.
Magn Reson Med ; 90(5): 1889-1904, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37382246

RESUMO

PURPOSE: Arterial spin labeling (ASL) acquisitions at multiple post-labeling delays may provide more accurate quantification of cerebral blood flow (CBF), by fitting appropriate kinetic models and simultaneously estimating relevant parameters such as the arterial transit time (ATT) and arterial cerebral blood volume (aCBV). We evaluate the effects of denoising strategies on model fitting and parameter estimation when accounting for the dispersion of the label bolus through the vasculature in cerebrovascular disease. METHODS: We analyzed multi-delay ASL data from 17 cerebral small vessel disease patients (50 ± 9 y) and 13 healthy controls (52 ± 8 y), by fitting an extended kinetic model with or without bolus dispersion. We considered two denoising strategies: removal of structured noise sources by independent component analysis (ICA) of the control-label image timeseries; and averaging the repetitions of the control-label images prior to model fitting. RESULTS: Modeling bolus dispersion improved estimation precision and impacted parameter values, but these effects strongly depended on whether repetitions were averaged before model fitting. In general, repetition averaging improved model fitting but adversely affected parameter values, particularly CBF and aCBV near arterial locations in patients. This suggests that using all repetitions allows better noise estimation at the earlier delays. In contrast, ICA denoising improved model fitting and estimation precision while leaving parameter values unaffected. CONCLUSION: Our results support the use of ICA denoising to improve model fitting to multi-delay ASL and suggest that using all control-label repetitions improves the estimation of macrovascular signal contributions and hence perfusion quantification near arterial locations. This is important when modeling flow dispersion in cerebrovascular pathology.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Marcadores de Spin , Encéfalo/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Artérias , Circulação Cerebrovascular/fisiologia , Imagem de Perfusão/métodos
20.
Nutrients ; 15(6)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36986038

RESUMO

The study of medicinal plants, such as the genus Garcinia (Clusiaceae), in the treatment of non-communicable chronic diseases has aroused the interest of researchers. However, there are no studies in the literature that have investigated the effects of Garcinia gardneriana in experimental models of obesity for possible metabolic alterations. Swiss mice receiving a high-fat diet were supplemented with aqueous or ethanolic extract of G. gardneriana at doses of 200 or 400 mg/kg/day. It was found that there was a reduction in food consumption in experimental groups compared with the control groups, and the group supplemented with aqueous extract at a dose of 200 mg/kg/daydisplayed a reduction in weight. The results showed an increase in the values of high density lipoprotein (HDL-c), total cholesterol, triglycerides and fasting blood glucose. G. gardneriana did not protect against insulin resistance, and caused in an increase in monocyte chemoattractant protein-1 (MCP-1) concentrations and a reduction in interleukin 10 (IL-10). In addition, hepatic steatosis and microvesicular steatosis were indicated. It was revealed that, under the experimental conditions in the study, G. gardneriana did not prevent weight gain or comorbidities; that is, a different behavior was obtained from that described in the literature with regard to the medicinal potential of the Garcinia species, which is probably related to the phytochemical properties.


Assuntos
Fígado Gorduroso , Garcinia , Plantas Medicinais , Camundongos , Animais , Garcinia/química , Extratos Vegetais/farmacologia , Etanol , Água , Dieta Hiperlipídica/efeitos adversos
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