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1.
Stem Cells ; 35(4): 1065-1079, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27800660

RESUMO

Preclinical studies using bone marrow derived cells to treat traumatic brain injury have demonstrated efficacy in terms of blood-brain barrier preservation, neurogenesis, and functional outcomes. Phase 1 clinical trials using bone marrow mononuclear cells infused intravenously in children with severe traumatic brain injury demonstrated safety and potentially a central nervous system structural preservation treatment effect. This study sought to confirm the safety, logistic feasibility, and potential treatment effect size of structural preservation/inflammatory biomarker mitigation in adults to guide Phase 2 clinical trial design. Adults with severe traumatic brain injury (Glasgow Coma Scale 5-8) and without signs of irreversible brain injury were evaluated for entry into the trial. A dose escalation format was performed in 25 patients: 5 controls, followed 5 patients in each dosing cohort (6, 9, 12 ×106 cells/kg body weight), then 5 more controls. Bone marrow harvest, cell processing to isolate the mononuclear fraction, and re-infusion occurred within 48 hours after injury. Patients were monitored for harvest-related hemodynamic changes, infusional toxicity, and adverse events. Outcome measures included magnetic resonance imaging-based measurements of supratentorial and corpus callosal volumes as well as diffusion tensor imaging-based measurements of fractional anisotropy and mean diffusivity of the corpus callosum and the corticospinal tract at the level of the brainstem at 1 month and 6 months postinjury. Functional and neurocognitive outcomes were measured and correlated with imaging data. Inflammatory cytokine arrays were measured in the plasma pretreatment, posttreatment, and at 1 and 6 month follow-up. There were no serious adverse events. There was a mild pulmonary toxicity of the highest dose that was not clinically significant. Despite the treatment group having greater injury severity, there was structural preservation of critical regions of interest that correlated with functional outcomes. Key inflammatory cytokines were downregulated. Treatment of severe, adult traumatic brain injury using an intravenously delivered autologous bone marrow mononuclear cell infusion is safe and logistically feasible. There appears to be a treatment signal as evidenced by central nervous system structural preservation, consistent with previous pediatric trial data. Inflammatory biomarkers are downregulated after cell infusion. Stem Cells 2016 Video Highlight: https://youtu.be/UiCCPIe-IaQ Stem Cells 2017;35:1065-1079.


Assuntos
Células da Medula Óssea/citologia , Lesões Encefálicas Traumáticas/terapia , Leucócitos Mononucleares/transplante , Adulto , Comportamento , Biomarcadores/sangue , Lesões Encefálicas Traumáticas/sangue , Lesões Encefálicas Traumáticas/patologia , Corpo Caloso/patologia , Citocinas/sangue , Feminino , Substância Cinzenta/patologia , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Tratos Piramidais/patologia , Resultado do Tratamento
2.
Brain Connect ; 6(3): 238-48, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26798959

RESUMO

Spina bifida myelomeningocele (SBM) is commonly associated with anomalous development of the corpus callosum (CC) because of congenital partial hypogenesis and hydrocephalus-related hypoplasia. It represents a model disorder to examine the effects of early disruption of CC neurodevelopment and the plasticity of interhemispheric white matter connections. Diffusion tensor imaging was acquired on 76 individuals with SBM and 27 typically developing individuals, aged 8-36 years. Probabilistic tractography was used to isolate the interhemispheric connections between the posterior superior temporal lobes, which typically traverse the posterior third of the CC. Early disruption of CC development resulted in restructuring of interhemispheric connections through alternate commissures, particularly the anterior commissure (AC). These rerouted fibers were present in people with SBM and both CC hypoplasia and hypogenesis. In addition, microstructural integrity was reduced in the interhemispheric temporal tract in people with SBM, indexed by lower fractional anisotropy, axial diffusivity, and higher radial diffusivity. Interhemispheric temporal tract volume was positively correlated with total volume of the CC, such that more severe underdevelopment of the CC was associated with fewer connections between the posterior temporal lobes. Therefore, both the macrostructure and microstructure of this interhemispheric tract were reduced, presumably as a result of more extensive CC malformation. The current findings suggest that early disruption in CC development reroutes interhemispheric temporal fibers through both the AC and more anterior sections of the CC in support of persistent hypotheses that the AC may serve a compensatory function in atypical CC development.


Assuntos
Plasticidade Neuronal/fisiologia , Disrafismo Espinal/fisiopatologia , Lobo Temporal/fisiopatologia , Substância Branca/fisiopatologia , Adolescente , Adulto , Agenesia do Corpo Caloso/fisiopatologia , Estudos de Casos e Controles , Criança , Corpo Caloso/fisiopatologia , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino , Meningomielocele , Fibras Nervosas Mielinizadas , Vias Neurais/fisiopatologia
3.
Brain Lang ; 161: 45-56, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26307492

RESUMO

Little is known about the white matter integrity of cerebellar-cortical pathways in individuals with dyslexia. Building on previous findings of decreased volume in the anterior lobe of the cerebellum, we utilized novel cerebellar segmentation procedures and probabilistic tractography to examine tracts that connect the anterior lobe of the cerebellum and cortical regions typically associated with reading: the temporoparietal (TP), occipitotemporal (OT), and inferior frontal (IF) regions. The sample included 29 reading impaired children and 27 typical readers. We found greater fractional anisotropy (FA) for the poor readers in tracts connecting the cerebellum with TP and IF regions relative to typical readers. In the OT region, FA was greater for the older poor readers, but smaller for the younger ones. This study provides evidence for discrete, regionally-bound functions of the cerebellum and suggests that projections from the anterior cerebellum appear to have a regulatory effect on cortical pathways important for reading.


Assuntos
Cerebelo/citologia , Cerebelo/fisiologia , Córtex Cerebral/citologia , Córtex Cerebral/fisiologia , Dislexia/fisiopatologia , Vias Neurais , Leitura , Substância Branca/fisiologia , Adolescente , Anisotropia , Estudos de Casos e Controles , Criança , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Probabilidade , Substância Branca/citologia
5.
Microsc Res Tech ; 73(3): 187-94, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19725070

RESUMO

Various deconvolution algorithms are often used for restoration of digital images. Image deconvolution is especially needed for the correction of three-dimensional images obtained by confocal laser scanning microscopy. Such images suffer from distortions, particularly in the Z dimension. As a result, reliable automatic segmentation of these images may be difficult or even impossible. Effective deconvolution algorithms are memory-intensive and time-consuming. In this work, we propose a parallel version of the well-known Richardson-Lucy deconvolution algorithm developed for a system with distributed memory and implemented with the use of Message Passing Interface (MPI). It enables significantly more rapid deconvolution of two-dimensional and three-dimensional images by efficiently splitting the computation across multiple computers. The implementation of this algorithm can be used on professional clusters provided by computing centers as well as on simple networks of ordinary PC machines.


Assuntos
Encéfalo/citologia , Imageamento Tridimensional/métodos , Microscopia Confocal/métodos , Neuroglia/química , Neuroglia/citologia , Algoritmos , Animais , Imuno-Histoquímica , Modelos Teóricos , Ratos
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