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1.
J Clin Med ; 12(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37834764

RESUMO

Parkinson's disease (PD) is a severe neurological disease for which there is no effective treatment or cure, and therefore it remains an unmet need in medicine. We present data from four participants who received autologous transplantation of small pieces of sural nerve tissue into either the basal forebrain containing the nucleus basalis of Meynert (NBM) or the midbrain substantia nigra (SN). The grafts did not exhibit significant cell death or severe host-tissue reaction up to 55 months post-grafting and contained peripheral cells. Dopaminergic neurites showed active growth in the graft area and into the graft in the SN graft, and cholinergic neurites were abundant near the graft in the NBM. These results provide a histological basis for changes in clinical features after autologous peripheral nerve tissue grafting into the NBM or SN in PD.

2.
BMJ Neurol Open ; 4(2): e000301, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35949912

RESUMO

Objective: To evaluate the interim feasibility, safety and clinical measures data of direct delivery of regenerating peripheral nerve tissue (PNT) to the substantia nigra (SN) in participants with Parkinson's disease (PD). Methods: Eighteen (13 men/5 women) participants were unilaterally implanted with PNT to the SN, contralateral to the most affected side during the same surgery they were receiving deep brain stimulation (DBS) surgery. Autologous PNT was collected from the sural nerve. Participants were followed for safety and clinical outcomes for 2 years (including off-state Unified Parkinson's Disease Rating Scale (UPDRS) Part III assessments) with study visits every 6 months. Results: All 18 participants scheduled to receive PNT implantation received targeted delivery to the SN in addition to their DBS. All subjects were discharged the following day except for two: post-op day 2; post-op day 3. The most common study-related adverse events were hypoaesthesia and hyperaesthesias to the lateral aspect of the foot and ankle of the biopsied nerve (6 of 18 participants experienced). Clinical measures did not identify any hastening of PD measures providing evidence of safety and tolerability. Off-state UPDRS Part III mean difference scores were reduced at 12 months compared with baseline (difference=-8.1, 95% CI -2.4 to -13.9 points, p=0.005). No complications involving dyskinesias were observed. Conclusions: Targeting the SN for direct delivery of PNT was feasible with no serious adverse events related to the study intervention. Interim clinical outcomes show promising results meriting continued examination of this investigational approach. Trial registration number: NCT02369003.

3.
Neurology ; 97(20): 942-957, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34782410

RESUMO

BACKGROUND AND OBJECTIVES: To review the current evidence on the options available for initiating dopaminergic treatment of motor symptoms in early-stage Parkinson disease and provide recommendations to clinicians. METHODS: A multidisciplinary panel developed practice recommendations, integrating findings from a systematic review and following an Institute of Medicine-compliant process to ensure transparency and patient engagement. Recommendations were supported by structured rationales, integrating evidence from the systematic review, related evidence, principles of care, and inferences from evidence. RESULTS: Initial treatment with levodopa provides superior motor benefit compared to treatment with dopamine agonists, whereas levodopa is more likely than dopamine agonists to cause dyskinesia. The comparison of different formulations of dopamine agonists yielded little evidence that any one formulation or method of administration is superior. Long-acting forms of levodopa and levodopa with entacapone do not appear to differ in efficacy from immediate-release levodopa for motor symptoms in early disease. There is a higher risk of impulse control disorders associated with the use of dopamine agonists than levodopa. Recommendations on initial therapy for motor symptoms are provided to assist the clinician and patient in choosing between treatment options and to guide counseling, prescribing, and monitoring of efficacy and safety.


Assuntos
Dopaminérgicos , Atividade Motora , Doença de Parkinson , Dopaminérgicos/efeitos adversos , Dopaminérgicos/uso terapêutico , Agonistas de Dopamina/efeitos adversos , Agonistas de Dopamina/uso terapêutico , Discinesia Induzida por Medicamentos , Humanos , Levodopa/efeitos adversos , Levodopa/uso terapêutico , Atividade Motora/fisiologia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/fisiopatologia , Guias de Prática Clínica como Assunto
4.
Brain Sci ; 11(4)2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33921079

RESUMO

BACKGROUND: The efficacy of deep brain stimulation (DBS) and dopaminergic therapy is known to decrease over time. Hence, a new investigational approach combines implanting autologous injury-activated peripheral nerve grafts (APNG) at the time of bilateral DBS surgery to the globus pallidus interna. OBJECTIVES: In a study where APNG was unilaterally implanted into the substantia nigra, we explored the effects on clinical gait and balance assessments over two years in 14 individuals with Parkinson's disease. METHODS: Computerized gait and balance evaluations were performed without medication, and stimulation was in the off state for at least 12 h to best assess the role of APNG implantation alone. We hypothesized that APNG might improve gait and balance deficits associated with PD. RESULTS: While people with a degenerative movement disorder typically worsen with time, none of the gait parameters significantly changed across visits in this 24 month study. The postural stability item in the UPDRS did not worsen from baseline to the 24-month follow-up. However, we measured gait and balance improvements in the two most affected individuals, who had moderate PD. In these two individuals, we observed an increase in gait velocity and step length that persisted over 6 and 24 months. CONCLUSIONS: Participants did not show worsening of gait and balance performance in the off therapy state two years after surgery, while the two most severely affected participants showed improved performance. Further studies may better address the long-term maintanenace of these results.

5.
J Neurosurg ; 129(6): 1550-1561, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29451447

RESUMO

OBJECTIVECurrently, there is no treatment that slows or halts the progression of Parkinson's disease. Delivery of various neurotrophic factors to restore dopaminergic function has become a focus of study in an effort to fill this unmet need for patients with Parkinson's disease. Schwann cells provide a readily available source of such factors. This study presents a 12-month evaluation of safety and feasibility, as well as the clinical response, of implanting autologous peripheral nerve grafts into the substantia nigra of patients with Parkinson's disease at the time of deep brain stimulation (DBS) surgery.METHODSStandard DBS surgery targeting the subthalamic nucleus was performed in 8 study participants. After DBS lead implantation, a section of the sural nerve containing Schwann cells was harvested and unilaterally grafted to the substantia nigra. Adverse events were continually monitored. Baseline clinical data were obtained during standard preoperative evaluations. Clinical outcome data were obtained with postoperative clinical evaluations, neuropsychological testing, and MRI at 1 year after surgery.RESULTSAll 8 participants were implanted with DBS systems and grafts. Adverse event profiles were comparable to those of standard DBS surgery with the exception of 1 superficial infection at the sural nerve harvest site. Three participants also reported numbness in the distribution of the sural nerve distal to the harvest site. Motor scores on Unified Parkinson's Disease Rating Scale (UPDRS) part III while the participant was off therapy at 12 months improved from baseline (mean ± SD 25.1 ± 15.9 points at 12 months vs 32.5 ± 9.7 points at baseline). An analysis of the lateralized UPDRS scores also showed a greater overall reduction in scores on the side contralateral to the graft.CONCLUSIONSPeripheral nerve graft delivery to the substantia nigra at the time of DBS surgery is feasible and safe based on the results of this initial pilot study. Clinical outcome data from this phase I trial suggests that grafting may have some clinical benefit and certainly warrants further study to determine if this is an efficacious and neurorestorative therapy.Clinical trial registration no.: NCT01833364 (clinicaltrials.gov).


Assuntos
Estimulação Encefálica Profunda , Transferência de Nervo/métodos , Doença de Parkinson/cirurgia , Nervos Periféricos/transplante , Substância Negra/cirurgia , Idoso , Eletrodos Implantados , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Transferência de Nervo/efeitos adversos , Testes Neuropsicológicos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/psicologia , Projetos Piloto , Substância Negra/diagnóstico por imagem , Resultado do Tratamento
6.
J Neurosurg ; 126(4): 1140-1147, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27153166

RESUMO

OBJECTIVE One avenue of intense efforts to treat Parkinson's disease (PD) involves the delivery of neurotrophic factors to restore dopaminergic cell function. A source of neurotrophic factors that could be used is the Schwann cell from the peripheral nervous system. The authors have begun an open-label safety study to examine the safety and feasibility of implanting an autologous peripheral nerve graft into the substantia nigra of PD patients undergoing deep brain stimulation (DBS) surgery. METHODS Multistage DBS surgery targeting the subthalamic nucleus was performed using standard procedures in 8 study participants. After the DBS leads were implanted, a section of sural nerve containing Schwann cells was excised and unilaterally delivered into the area of the substantia nigra. Adverse events were continuously monitored. RESULTS Eight of 8 participants were implanted with DBS systems and grafts. Adverse event profiles were comparable to those of standard DBS surgery. Postoperative MR images did not reveal edema, hemorrhage, or significant signal changes in the graft target region. Three participants reported a patch of numbness on the outside of the foot below the sural nerve harvest site. CONCLUSIONS Based on the safety outcome of the procedure, targeted peripheral nerve graft delivery to the substantia nigra at the time of DBS surgery is feasible and may provide a means to deliver neurorestorative therapy. Clinical trial registration no.: NCT01833364 ( clinicaltrials.gov ).


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson/terapia , Nervos Periféricos/transplante , Substância Negra/cirurgia , Estimulação Encefálica Profunda/métodos , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico por imagem , Substância Negra/diagnóstico por imagem , Núcleo Subtalâmico/diagnóstico por imagem , Núcleo Subtalâmico/cirurgia , Resultado do Tratamento
7.
J Neurovirol ; 18(5): 411-5, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22585288

RESUMO

Natalizumab-associated progressive multifocal leukoencephalopathy in multiple sclerosis (MS) occurred in two individuals also treated with interferon ß1a, raising concerns about the interaction of these disease-modifying agents and leading to the recommendation to avoid their concomitant administration. However, type I interferons are antiviral. Using a real-time quantitative polymerase chain reaction for the detection and quantification of the John Cunningham virus (JCV), DNA in peripheral blood mononuclear cells (PBMCs), and urine in MS patients, we tested the hypothesis that MS disease-modifying drugs (DMD) qualitatively and quantitatively alter JCV prevalence and viral copy numbers. Two hundred thirty-nine patients were enrolled in a cross-sectional study in which blood and urine specimens were collected at a single time and 37 newly diagnosed, treatment-naïve MS patients were enrolled in a longitudinal study in which specimens were obtained at diagnosis and 6 months after treatment initiation. JCV DNA was detected in PBMCs of only two patients (0.07 %), but was commonly detected in the urine (46.8 %) in this population. There was no effect of DMDs on blood or urinary JCV prevalence or viral copy numbers with either glatiramer acetate (Copaxone®) or interferon-ß therapy (Avonex®, Betaseron®, or Rebif®). The small number of patients on other therapies precluded meaningful comment about their effects. No obvious effect of the platform DMDs on JCV prevalence was observed even for the interferon-ßs.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Interferon beta/uso terapêutico , Vírus JC/efeitos dos fármacos , Leucoencefalopatia Multifocal Progressiva/tratamento farmacológico , Esclerose Múltipla/tratamento farmacológico , Adolescente , Adulto , Idoso , Inibição de Migração Celular , Estudos Transversais , DNA Viral/genética , Quimioterapia Combinada , Feminino , Acetato de Glatiramer , Humanos , Vírus JC/genética , Vírus JC/crescimento & desenvolvimento , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/virologia , Leucoencefalopatia Multifocal Progressiva/sangue , Leucoencefalopatia Multifocal Progressiva/urina , Leucoencefalopatia Multifocal Progressiva/virologia , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/sangue , Esclerose Múltipla/urina , Esclerose Múltipla/virologia , Natalizumab , Peptídeos/uso terapêutico , Reação em Cadeia da Polimerase , Carga Viral/efeitos dos fármacos
9.
Glia ; 50(2): 91-106, 2005 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15630704

RESUMO

Recent evidence suggests that injection drug users who abuse heroin are at increased risk of CNS complications from human immunodeficiency virus (HIV) infection. Opiate drugs may intrinsically alter the pathogenesis of HIV by directly modulating immune function and by directly modifying the CNS response to HIV. Despite this, the mechanisms by which opiates increase the neuropathogenesis of HIV are uncertain. In the present study, we describe the effect of morphine and the HIV-1 protein toxin Tat(1-72) on astroglial function in cultures derived from ICR mice. Astroglia maintain the blood-brain barrier and influence inflammatory signaling in the CNS. Astrocytes can express mu-opioid receptors, and are likely targets for abused opiates, which preferentially activate mu-opioid receptors. While Tat alone disrupts astrocyte function, when combined with morphine, Tat causes synergistic increases in [Ca(2+)](i). Moreover, astrocyte cultures treated with morphine and Tat showed exaggerated increases in chemokine release, including monocyte chemoattractant protein-1 (MCP-1) and regulated on activation, normal T cell expressed and secreted (RANTES), as well as interleukin-6 (IL-6). Morphine-Tat interactions were prevented by the mu-opioid receptor antagonist beta-funaltrexamine, or by immunoneutralizing Tat(1-72) or substituting a nontoxic, deletion mutant (Tat(Delta31-61)). Our findings suggest that opiates may increase the vulnerability of the CNS to viral entry (via recruitment of monocytes/macrophages) and ensuing HIV encephalitis by synergistically increasing MCP-1 and RANTES release by astrocytes. The results further suggest that astrocytes are key intermediaries in opiate-HIV interactions and disruptions in astroglial function and inflammatory signaling may contribute to an accelerated neuropathogenesis in HIV-infected individuals who abuse opiates.


Assuntos
Astrócitos/metabolismo , Cálcio/farmacologia , Quimiocina CCL2/metabolismo , Quimiocina CCL5/metabolismo , Produtos do Gene tat/metabolismo , HIV-1/metabolismo , Interleucina-6/metabolismo , Entorpecentes/farmacologia , Analgésicos Opioides/farmacologia , Animais , Astrócitos/efeitos dos fármacos , Cálcio/metabolismo , Células Cultivadas , Citocinas/metabolismo , Sinergismo Farmacológico , Homeostase/fisiologia , Humanos , Cinética , Camundongos , Camundongos Endogâmicos ICR , Microglia/metabolismo , Morfina/farmacologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores Opioides mu/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Produtos do Gene tat do Vírus da Imunodeficiência Humana
10.
J Neurobiol ; 51(4): 285-301, 2002 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-12150504

RESUMO

Neuronal growth cones are capable of sophisticated discrimination of environmental cues, on cell surfaces and in the extracellular matrix, to accomplish navigation during development (generation) and following nervous system injury (regeneration). Choices made by growth cones are commonly examined using tissue culture paradigms in which molecules of interest are purified and substratum-bound. From observations of growth cone behaviors using these paradigms, assertions are made about choices neuronal growth cones may make in vivo. However, in many cases, the binding, interactions, and conformations of these molecules have not been determined. In the present study, we investigated the binding characteristics of two commonly studied outgrowth regulatory molecules: chondroitin sulfate proteoglycans (CSPGs), which are typically inhibitory to neurite outgrowth during development and following nervous system injury, and laminin, which is typically outgrowth promoting for many neuronal types. Using a novel combination of radiolabeling and quantitative fluorescence, we determined the precise concentrations of CSPGs and laminin-1 that were bound separately and together in a variety of choice assays. For identically prepared cultures, we correlated neurite outgrowth behaviors with binding characteristics. The data support-our working hypothesis that neuronal growth cones are guided by the ratio of outgrowth-promoting to outgrowth-inhibiting influences in their environment, i.e., they summate local molecular cues. The response of growth cones to these molecular combinations is most likely mediated by integrins and subsequent activation of signal transduction cascades in growth cones.


Assuntos
Proteoglicanas de Sulfatos de Condroitina/metabolismo , Cones de Crescimento/metabolismo , Laminina/metabolismo , Animais , Ligação Competitiva , Embrião de Galinha , Técnicas de Cultura , Matriz Extracelular/metabolismo , Gânglios Espinais/metabolismo , Cinética , Fatores de Tempo
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