RESUMO
PURPOSE: In deep burns, wound contraction and hypertrophic scar formation can generate functional derangement and debilitation of the affected part. In order to improve the quality of healing in deep second-degree burns, we developed a new treatment in a preclinical model using nanostructured membranes seeded with mesenchymal stem cells (MSCs). METHODS: Membranes were obtained by reconstitution of bacterial cellulose (reconstituted membrane [RM]) and produced by a dry-cast process, then RM was incorporated with 10% tamarind xyloglucan plus gellan gum 1:1 and 10% lysozyme (RMGT-LZ) and with 10% gellan gum and 10% lysozyme (RMG-LZ). Membrane hydrophobic/hydrophilic characteristics were investigated by static/dynamic contact-angle measurements. They were cultivated with MSCs, and cell adhesion, proliferation, and migration capacity was analyzed with MTT assays. Morphological and topographic characteristics were analyzed by scanning electron microscopy. MSC patterns in flow cytometry and differentiation into adipocytes and osteocytes were checked. In vivo assays used RMG-LZ and RMGT-LZ (with and without MSCs) in Rattus norvegicus rats submitted to burn protocol, and histological sections and collagen deposits were analyzed and immunocytochemistry assay performed. RESULTS: In vitro results demonstrated carboxyl and amine groups made the membranes moderately hydrophobic and xyloglucan inclusion decreased wettability, favoring MSC adhesion, proliferation, and differentiation. In vivo, we obtained 40% and 60% reduction in acute/chronic inflammatory infiltrates, 96% decrease in injury area, increased vascular proliferation and collagen deposition, and complete epithelialization after 30 days. MSCs were detected in burned tissue, confirming they had homed and proliferated in vivo. CONCLUSION: Nanostructured cellulose-gellan-xyloglucan-lysozyme dressings, especially when seeded with MSCs, improved deep second-degree burn regeneration.
Assuntos
Bandagens , Queimaduras/terapia , Celulose/química , Glucanos/química , Células-Tronco Mesenquimais/citologia , Muramidase/química , Nanoestruturas/química , Polissacarídeos Bacterianos/química , Xilanos/química , Animais , Vasos Sanguíneos/patologia , Queimaduras/patologia , Adesão Celular , Diferenciação Celular , Proliferação de Células , Celulose/ultraestrutura , Colágeno/metabolismo , Inflamação/patologia , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/ultraestrutura , Nanoestruturas/ultraestrutura , Ratos Wistar , CicatrizaçãoRESUMO
Dystonia is a disabling movement disorder characterized by co-contraction of antagonist and agonist muscles, leading to abnormal sustained postures and impaired motor control. Cervical Dystonia (CD) and Hand Focal Dystonia (HFD) have been the most common forms of focal dystonia (FD). Do Non-Invasive Brain Neuromodulation (NIBS) such as Transcranial Direct Current Stimulation (tDCS) and repetitive Transcranial Magnetic Stimulation (rTMS) modulate the excitability of the connections between the motor cortical areas and may represent a therapeutic alternative for focal dystonia? Herein, we reported three cases of focal dystonia, two of them with cervical dystonia (CD) and one with hand focal dystonia (HFD), treated with NIBS combined to kinesiotherapy. The patients were daily submitted to 15 sessions of NIBS combined simultaneously with kinesiotherapy. CD patients were treated with tDCS (2 mA, 20 min, over the primary motor cortex), and HFD patient with rTMS (1 Hz, 1200 pulses, 80% of resting motor threshold, over the premotor cortex). For the CD patient's assessment, the Modified Toronto Scale for Cervical Dystonia Assessment (MTS), quiet balance test, and visual postural assessment were applied to observe the therapeutic effects. Quality handwriting analysis, tremor acceleration amplitudes, and the Wrinter's Cramp Rating Scale (WCRS) were used to assess the NIBS effect on HFD symptoms. Patients were evaluated before (pretest), immediately after (posttest), and three months after treatment (retention). NIBS associated with kinesiotherapy produced a long-term improvement of dystonia symptoms in all three patients. rTMS and tDCS associated with kinesiotherapy showed to be useful and safe to relief the dystonia symptoms in individuals with different types of focal dystonia with distinct functional disorders. SIGNIFICANCE: The combined use of these intervention strategies seems to optimize and anticipate satisfactory clinical results in these neurological conditions, characterized by its difficult clinical management.
Assuntos
Distúrbios Distônicos/terapia , Estimulação Transcraniana por Corrente Contínua , Estimulação Magnética Transcraniana , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/fisiopatologia , Técnicas Estereotáxicas , TorcicoloRESUMO
Knowledge of brain correlates of postural control is limited by the technical difficulties in performing controlled experiments with currently available neuroimaging methods. Here we present a system that allows the measurement of anticipatory postural adjustment of human legs to be synchronized with the acquisition of functional magnetic resonance imaging data. The device is composed of Magnetic Resonance Imaging (MRI) compatible force sensors able to measure the level of force applied by both feet. We tested the device in a group of healthy young subjects and a group of elderly subjects with Parkinson's disease using an event-related functional MRI (fMRI) experiment design. In both groups the postural behavior inside the magnetic resonance was correlated to the behavior during gait initiation outside the scanner. The system did not produce noticeable imaging artifacts in the data. Healthy young people showed brain activation patterns coherent with movement planning. Parkinson's disease patients demonstrated an altered pattern of activation within the motor circuitry. We concluded that this force measurement system is able to index both normal and abnormal preparation for gait initiation within an fMRI experiment.
Assuntos
Marcha , Fenômenos Mecânicos , Córtex Motor/fisiopatologia , Doença de Parkinson/fisiopatologia , Equilíbrio Postural , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Deep brain stimulation and levodopatherapy ameliorate motor manifestations in Parkinson's disease, but their effects on axial signs are not sustained in the long term. OBJECTIVES: The objective of this study was to investigate the safety and efficacy of spinal cord stimulation on gait disturbance in advanced Parkinson's disease. METHODS: A total of 4 Parkinson's disease patients who experienced significant postural instability and gait disturbance years after chronic subthalamic stimulation were treated with spinal cord stimulation at 300 Hz. Timed-Up-GO and 20-meter-walk tests, UPDRS III, freezing of gait questionnaire, and quality-of-life scores were measured at 6 months and compared to baseline values. Blinded assessments to measure performance in the Timed-Up-GO and 20-meter-walk tests were carried out during sham stimulation at 300 Hz and 60 Hz. RESULTS: Patients treated with spinal cord stimulation had approximately 50% to 65% improvement in gait measurements and 35% to 45% in UPDRS III and quality-of-life scores. During blinded evaluations, significant improvements in the Timed-Up-GO and 20-meter-walk tests were only recorded at 300 Hz. CONCLUSION: Spinal cord stimulation at 300 Hz was well tolerated and led to a significant improvement in gait. © 2016 International Parkinson and Movement Disorder Society.