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1.
Cereb Cortex ; 33(23): 11257-11268, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37859521

RESUMO

When brain regions that are critical for a cognitive function in adulthood are irreversibly damaged at birth, what patterns of plasticity support the successful development of that function in an alternative location? Here we investigate the consistency of language organization in the right hemisphere (RH) after a left hemisphere (LH) perinatal stroke. We analyzed fMRI data collected during an auditory sentence comprehension task on 14 people with large cortical LH perinatal arterial ischemic strokes (left hemisphere perinatal stroke (LHPS) participants) and 11 healthy sibling controls using a "top voxel" approach that allowed us to compare the same number of active voxels across each participant and in each hemisphere for controls. We found (1) LHPS participants consistently recruited the same RH areas that were a mirror-image of typical LH areas, and (2) the RH areas recruited in LHPS participants aligned better with the strongly activated LH areas of the typically developed brains of control participants (when flipped images were compared) than the weakly activated RH areas. Our findings suggest that the successful development of language processing in the RH after a LH perinatal stroke may in part depend on recruiting an arrangement of frontotemporal areas reflective of the typical dominant LH.


Assuntos
Transtornos da Linguagem , Acidente Vascular Cerebral , Recém-Nascido , Humanos , Idioma , Acidente Vascular Cerebral/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Compreensão , Imageamento por Ressonância Magnética , Lateralidade Funcional
2.
J Cereb Blood Flow Metab ; 43(12): 2130-2143, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37694957

RESUMO

Few have characterized miRNA expression during the transition from injury to neural repair and secondary neurodegeneration following stroke in humans. We compared expression of 754 miRNAs from plasma samples collected 5, 15, and 30 days post-ischemic stroke from a discovery cohort (n = 55) and 15-days post-ischemic stroke from a validation cohort (n = 48) to healthy control samples (n = 55 and 48 respectively) matched for age, sex, race and cardiovascular comorbidities using qRT-PCR. Eight miRNAs remained significantly altered across all time points in both cohorts including many described in acute stroke. The number of significantly dysregulated miRNAs more than doubled from post-stroke day 5 (19 miRNAs) to days 15 (50 miRNAs) and 30 (57 miRNAs). Twelve brain-enriched miRNAs were significantly altered at one or more time points (decreased expression, stroke versus controls: miR-107; increased expression: miR-99-5p, miR-127-3p, miR-128-3p, miR-181a-3p, miR-181a-5p, miR-382-5p, miR-433-3p, miR-491-5p, miR-495-3p, miR-874-3p, and miR-941). Many brain-enriched miRNAs were associated with apoptosis over the first month post-stroke whereas other miRNAs suggested a transition to synapse regulation and neuronal protection by day 30. These findings suggest that a program of decreased cellular proliferation may last at least 30 days post-stroke, and points to specific miRNAs that could contribute to neural repair in humans.


Assuntos
AVC Isquêmico , MicroRNAs , Acidente Vascular Cerebral , Humanos , MicroRNAs/metabolismo , Acidente Vascular Cerebral/genética , Encéfalo/metabolismo , Estudos de Casos e Controles , Perfilação da Expressão Gênica
3.
Arch Rehabil Res Clin Transl ; 5(3): 100282, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37744191

RESUMO

Objective: To present the development of a novel upper extremity (UE) treatment and assess how it was delivered in the Critical Periods After Stroke Study (CPASS), a phase II randomized controlled trial (RCT). Design: Secondary analysis of data from the RCT. Setting: Inpatient and outpatient settings the first year after stroke. Participants: Of the 72 participants enrolled in CPASS (N=72), 53 were in the study groups eligible to receive the treatment initiated at ≤30 days (acute), 2-3 months (subacute), or ≥6 months (chronic) poststroke. Individuals were 65.1±10.5 years of age, 55% were women, and had mild to moderate UE motor capacity (Action Research Arm Test=17.2±14.3) at baseline. Intervention: The additional 20 hours of treatment began using the Activity Card Sort (ACS), a standardized assessment of activities and participation after stroke, to identify UE treatment goals selected by the participants that were meaningful to them. Treatment activities were broken down into smaller components from a standardized protocol and process that operationalized the treatments essential elements. Main Outcome Measures: Feasibility of performing the treatment in a variety of clinical settings in an RCT and contextual factors that influenced adherence. Results: A total of 49/53 participants fully adhered to the CPASS treatment. The duration and location of the treatment sessions and the UE activities practiced during therapy are presented for the total sample (n=49) and per study group as an assessment of feasibility and the contextual factors that influenced adherence. Conclusions: The CPASS treatment and therapy goals were explicitly based on the meaningful activities identified by the participants using the ACS as a treatment planning tool. This approach provided flexibility to customize UE motor therapy without sacrificing standardization or quantification of the data regardless of the location and UE impairments of participants within the first year poststroke.

4.
Neurorehabil Neural Repair ; 37(1): 76-79, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36575958

RESUMO

The Critical Periods After Stroke Study (CPASS, n = 72) showed that, compared to controls, an additional 20 hours of intensive upper limb therapy led to variable gains on the Action Research Arm Test depending on when therapy was started post-stroke: the subacute group (2-3 months) improved beyond the minimal clinically important difference and the acute group (0-1 month) showed smaller but statistically significant improvement, but the chronic group (6-9 months) did not demonstrate improvement that reached significance. Some have misinterpreted CPASS results to indicate that all inpatient motor therapy should be shifted to outpatient therapy delivered 2 to 3 months post-stroke. Instead, however, CPASS argues for a large dose of motor therapy delivered continuously and cumulatively during the acute and subacute phases. When interpreting trials like CPASS, one must consider the substantial dose of early usual customary care (UCC) motor therapy that all participants received. CPASS participants averaged 27.9 hours of UCC occupational therapy (OT) during the first 2 months and 9.8 hours of UCC OT during the third and fourth months post-stroke. Any recovery experienced would therefore result not just from CPASS intensive motor therapy but the combined effects of experimental therapy plus UCC. Statistical limitations also did not allow direct comparisons of the acute and subacute group outcomes in CPASS. Instead of shifting inpatient therapy hours to the subacute phase, CPASS argues for preserving inpatient UCC. We also recommend conducting multi-site dosing trials to determine whether additional intensive motor therapy delivered in the first 2 to 3 months following inpatient rehabilitation can further improve outcomes.


Assuntos
Terapia Ocupacional , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/terapia , Terapia Ocupacional/métodos , Terapia por Exercício/métodos , Paresia/reabilitação , Extremidade Superior , Recuperação de Função Fisiológica
5.
Proc Natl Acad Sci U S A ; 119(42): e2207293119, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36215488

RESUMO

The mature human brain is lateralized for language, with the left hemisphere (LH) primarily responsible for sentence processing and the right hemisphere (RH) primarily responsible for processing suprasegmental aspects of language such as vocal emotion. However, it has long been hypothesized that in early life there is plasticity for language, allowing young children to acquire language in other cortical regions when LH areas are damaged. If true, what are the constraints on functional reorganization? Which areas of the brain can acquire language, and what happens to the functions these regions ordinarily perform? We address these questions by examining long-term outcomes in adolescents and young adults who, as infants, had a perinatal arterial ischemic stroke to the LH areas ordinarily subserving sentence processing. We compared them with their healthy age-matched siblings. All participants were tested on a battery of behavioral and functional imaging tasks. While stroke participants were impaired in some nonlinguistic cognitive abilities, their processing of sentences and of vocal emotion was normal and equal to that of their healthy siblings. In almost all, these abilities have both developed in the healthy RH. Our results provide insights into the remarkable ability of the young brain to reorganize language. Reorganization is highly constrained, with sentence processing almost always in the RH frontotemporal regions homotopic to their location in the healthy brain. This activation is somewhat segregated from RH emotion processing, suggesting that the two functions perform best when each has its own neural territory.


Assuntos
Idioma , Acidente Vascular Cerebral , Adolescente , Encéfalo/fisiologia , Mapeamento Encefálico/métodos , Criança , Pré-Escolar , Lateralidade Funcional/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Plasticidade Neuronal/fisiologia , Adulto Jovem
6.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34544853

RESUMO

Restoration of human brain function after injury is a signal challenge for translational neuroscience. Rodent stroke recovery studies identify an optimal or sensitive period for intensive motor training after stroke: near-full recovery is attained if task-specific motor training occurs during this sensitive window. We extended these findings to adult humans with stroke in a randomized controlled trial applying the essential elements of rodent motor training paradigms to humans. Stroke patients were adaptively randomized to begin 20 extra hours of self-selected, task-specific motor therapy at ≤30 d (acute), 2 to 3 mo (subacute), or ≥6 mo (chronic) after stroke, compared with controls receiving standard motor rehabilitation. Upper extremity (UE) impairment assessed by the Action Research Arm Test (ARAT) was measured at up to five time points. The primary outcome measure was ARAT recovery over 1 y after stroke. By 1 y we found significantly increased UE motor function in the subacute group compared with controls (ARAT difference = +6.87 ± 2.63, P = 0.009). The acute group compared with controls showed smaller but significant improvement (ARAT difference = +5.25 ± 2.59 points, P = 0.043). The chronic group showed no significant improvement compared with controls (ARAT = +2.41 ± 2.25, P = 0.29). Thus task-specific motor intervention was most effective within the first 2 to 3 mo after stroke. The similarity to rodent model treatment outcomes suggests that other rodent findings may be translatable to human brain recovery. These results provide empirical evidence of a sensitive period for motor recovery in humans.


Assuntos
Atividade Motora/fisiologia , Recuperação de Função Fisiológica , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/terapia , Idoso , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos
7.
Front Hum Neurosci ; 9: 231, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25972803

RESUMO

INTRODUCTION: Seven hundred ninety-five thousand Americans will have a stroke this year, and half will have a chronic hemiparesis. Substantial animal literature suggests that the mammalian brain has much potential to recover from acute injury using mechanisms of neuroplasticity, and that these mechanisms can be accessed using training paradigms and neurotransmitter manipulation. However, most of these findings have not been tested or confirmed in the rehabilitation setting, in large part because of the challenges in translating a conceptually straightforward laboratory experiment into a meaningful and rigorous clinical trial in humans. Through presentation of methods for a Phase II trial, we discuss these issues and describe our approach. METHODS: In rodents there is compelling evidence for timing effects in rehabilitation; motor training delivered at certain times after stroke may be more effective than the same training delivered earlier or later, suggesting that there is a critical or sensitive period for strongest rehabilitation training effects. If analogous critical/sensitive periods can be identified after human stroke, then existing clinical resources can be better utilized to promote recovery. The Critical Periods after Stroke Study (CPASS) is a phase II randomized, controlled trial designed to explore whether such a sensitive period exists. We will randomize 64 persons to receive an additional 20 h of upper extremity therapy either immediately upon rehab admission, 2-3 months after stroke onset, 6 months after onset, or to an observation-only control group. The primary outcome measure will be the Action Research Arm Test (ARAT) at 1 year. Blood will be drawn at up to 3 time points for later biomarker studies. CONCLUSION: CPASS is an example of the translation of rodent motor recovery experiments into the clinical setting; data obtained from this single site randomized controlled trial will be used to finalize the design of a Phase III trial.

8.
Int J Stroke ; 6(5): 454-60, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21951411

RESUMO

RATIONALE: PROTECT DC examines whether stroke navigators can improve cardiovascular risk factors in urban underserved individuals newly hospitalized for stroke or ischemic attack. Within one-year of hospital discharge, up to one-third of patients no longer adhere to secondary prevention behaviors. Adherence rates are lower in minority-underserved groups, contributing to health disparities. In-hospital programs increase use of stroke prevention therapies but may not be as successful in underserved individuals. In these groups, low literacy, limited healthcare access, and sparse community resources may reduce adherence. Lay community health workers (navigators) improve adherence in other illnesses through education and assisting in overcoming barriers to achieving desired health behaviors and obtaining needed healthcare services. AIMS AND DESIGN: PROTECT DC is a Phase II, single-blind, randomized, controlled trial comparing in-hospital education plus stroke navigators to usual care. Atherogenic ischemic stroke and transient ischemic attack survivors are recruited from Washington, DC hospitals. Navigators meet with participants during the index hospitalization, perform home visits, and meet by phone. They focus on stroke education, medication compliance, and overcoming practical barriers to adherence. The interventions are driven by the theories of reasoned action and planned behavior. STUDY OUTCOMES: The primary dependent measure is a summary score of four objective measures of stroke risk factor control: systolic blood pressure, low-density lipoprotein, hemoglobin Hb A1C, and antiplatelet agent pill counts. Secondary outcomes include stroke knowledge, exercise, dietary modification, and smoking cessation. CONCLUSION: PROTECT DC will determine whether a Phase III trial of stroke navigation for urban underserved individuals to improve adherence to secondary stroke prevention behaviors is warranted.


Assuntos
Agentes Comunitários de Saúde , Educação de Pacientes como Assunto/organização & administração , Prevenção Secundária/organização & administração , Acidente Vascular Cerebral/prevenção & controle , Tromboembolia/prevenção & controle , Adulto , Negro ou Afro-Americano , Idoso , Complicações do Diabetes/sangue , Complicações do Diabetes/epidemiologia , Complicações do Diabetes/prevenção & controle , District of Columbia/epidemiologia , Dislipidemias/sangue , Dislipidemias/epidemiologia , Dislipidemias/terapia , Hemoglobinas Glicadas/análise , Hospitais Urbanos , Humanos , Hipertensão/epidemiologia , Hipertensão/terapia , Lipoproteínas LDL/sangue , Área Carente de Assistência Médica , Pessoa de Meia-Idade , Cooperação do Paciente , Inibidores da Agregação Plaquetária/uso terapêutico , Áreas de Pobreza , Centros de Reabilitação , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/terapia , Tromboembolia/epidemiologia , Tromboembolia/terapia , População Urbana
9.
Curr Neurol Neurosci Rep ; 7(2): 147-55, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17324366

RESUMO

Cerebral palsy is the most common developmental disorder causing a physical disability arising from an injury to the central nervous system. The majority of pediatric neurologists remain minimally involved in the rehabilitation of these children. Recent advances in basic and clinical neuroscience give hope that effective rehabilitation strategies, based on motor learning science, can be developed for these children. The aim of this review is to alert pediatric neurologists to these advances.


Assuntos
Paralisia Cerebral/reabilitação , Paralisia Cerebral/terapia , Destreza Motora , Plasticidade Neuronal , Paralisia Cerebral/fisiopatologia , Criança , Humanos
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