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1.
Dement Geriatr Cogn Disord ; 47(1-2): 19-28, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30630160

RESUMO

BACKGROUND/AIM: The prevalence of cognitive symptoms in recently diagnosed Parkinson's disease (PD) patients may be as high as 60%. We report a novel deep brain stimulation (DBS) strategy targeting both motor and cognitive symptoms. METHODS: A PD patient diagnosed with mild cognitive impairment underwent DBS surgery targeting the globus pallidus interna (GPi; to treat motor symptoms) and the nucleus basalis of Meynert (NBM; to treat cognitive symptoms) using a single electrode per hemisphere. RESULTS: Compared to baseline, 2-month follow-up after GPi stimulation was associated with motor improvements, whereas partial improvements in cognitive functions were observed 3 months after the addition of NBM stimulation to GPi stimulation. CONCLUSION: This case explores an available alternative for complete DBS treatment in PD, stimulating 2 targets at different frequencies with a single electrode lead.


Assuntos
Núcleo Basal de Meynert , Disfunção Cognitiva , Estimulação Encefálica Profunda/métodos , Globo Pálido , Destreza Motora , Idoso , Cognição , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
2.
Brain ; 139(Pt 1): 161-73, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26582559

RESUMO

Progressive supranuclear palsy and Parkinson's disease have distinct underlying neuropathology, but both diseases affect cognitive function in addition to causing a movement disorder. They impair response inhibition and may lead to impulsivity, which can occur even in the presence of profound akinesia and rigidity. The current study examined the mechanisms of cognitive impairments underlying disinhibition, using horizontal saccadic latencies that obviate the impact of limb slowness on executing response decisions. Nineteen patients with clinically diagnosed progressive supranuclear palsy (Richardson's syndrome), 24 patients with clinically diagnosed Parkinson's disease and 26 healthy control subjects completed a saccadic Go/No-Go task with a head-mounted infrared saccadometer. Participants were cued on each trial to make a pro-saccade to a horizontal target or withhold their responses. Both patient groups had impaired behavioural performance, with more commission errors than controls. Mean saccadic latencies were similar between all three groups. We analysed behavioural responses as a binary decision between Go and No-Go choices. By using Bayesian parameter estimation, we fitted a hierarchical drift-diffusion model to individual participants' single trial data. The model decomposes saccadic latencies into parameters for the decision process: decision boundary, drift rate of accumulation, decision bias, and non-decision time. In a leave-one-out three-way classification analysis, the model parameters provided better discrimination between patients and controls than raw behavioural measures. Furthermore, the model revealed disease-specific deficits in the Go/No-Go decision process. Both patient groups had slower drift rate of accumulation, and shorter non-decision time than controls. But patients with progressive supranuclear palsy were strongly biased towards a pro-saccade decision boundary compared to Parkinson's patients and controls. This indicates a prepotency of responding in combination with a reduction in further accumulation of evidence, which provides a parsimonious explanation for the apparently paradoxical combination of disinhibition and severe akinesia. The combination of the well-tolerated oculomotor paradigm and the sensitivity of the model-based analysis provides a valuable approach for interrogating decision-making processes in neurodegenerative disorders. The mechanistic differences underlying participants' poor performance were not observable from classical analysis of behavioural data, but were clearly revealed by modelling. These differences provide a rational basis on which to develop and assess new therapeutic strategies for cognition and behaviour in these disorders.


Assuntos
Tomada de Decisões , Inibição Neural , Doença de Parkinson/fisiopatologia , Doença de Parkinson/psicologia , Paralisia Supranuclear Progressiva/fisiopatologia , Paralisia Supranuclear Progressiva/psicologia , Idoso , Teorema de Bayes , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Modelos Neurológicos , Movimentos Sacádicos
3.
Brain ; 139(Pt 8): 2235-48, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27343257

RESUMO

Parkinson's disease impairs the inhibition of responses, and whilst impulsivity is mild for some patients, severe impulse control disorders affect ∼10% of cases. Based on preclinical models we proposed that noradrenergic denervation contributes to the impairment of response inhibition, via changes in the prefrontal cortex and its subcortical connections. Previous work in Parkinson's disease found that the selective noradrenaline reuptake inhibitor atomoxetine could improve response inhibition, gambling decisions and reflection impulsivity. Here we tested the hypotheses that atomoxetine can restore functional brain networks for response inhibition in Parkinson's disease, and that both structural and functional connectivity determine the behavioural effect. In a randomized, double-blind placebo-controlled crossover study, 19 patients with mild-to-moderate idiopathic Parkinson's disease underwent functional magnetic resonance imaging during a stop-signal task, while on their usual dopaminergic therapy. Patients received 40 mg atomoxetine or placebo, orally. This regimen anticipates that noradrenergic therapies for behavioural symptoms would be adjunctive to, not a replacement for, dopaminergic therapy. Twenty matched control participants provided normative data. Arterial spin labelling identified no significant changes in regional perfusion. We assessed functional interactions between key frontal and subcortical brain areas for response inhibition, by comparing 20 dynamic causal models of the response inhibition network, inverted to the functional magnetic resonance imaging data and compared using random effects model selection. We found that the normal interaction between pre-supplementary motor cortex and the inferior frontal gyrus was absent in Parkinson's disease patients on placebo (despite dopaminergic therapy), but this connection was restored by atomoxetine. The behavioural change in response inhibition (improvement indicated by reduced stop-signal reaction time) following atomoxetine correlated with structural connectivity as measured by the fractional anisotropy in the white matter underlying the inferior frontal gyrus. Using multiple regression models, we examined the factors that influenced the individual differences in the response to atomoxetine: the reduction in stop-signal reaction time correlated with structural connectivity and baseline performance, while disease severity and drug plasma level predicted the change in fronto-striatal effective connectivity following atomoxetine. These results suggest that (i) atomoxetine increases sensitivity of the inferior frontal gyrus to afferent inputs from the pre-supplementary motor cortex; (ii) atomoxetine can enhance downstream modulation of frontal-subcortical connections for response inhibition; and (iii) the behavioural consequences of treatment are dependent on fronto-striatal structural connections. The individual differences in behavioural responses to atomoxetine highlight the need for patient stratification in future clinical trials of noradrenergic therapies for Parkinson's disease.


Assuntos
Inibidores da Captação Adrenérgica/farmacologia , Cloridrato de Atomoxetina/farmacologia , Corpo Estriado , Dopaminérgicos/uso terapêutico , Função Executiva/efeitos dos fármacos , Inibição Psicológica , Rede Nervosa , Avaliação de Resultados em Cuidados de Saúde , Doença de Parkinson , Córtex Pré-Frontal , Índice de Gravidade de Doença , Inibidores da Captação Adrenérgica/administração & dosagem , Inibidores da Captação Adrenérgica/sangue , Idoso , Cloridrato de Atomoxetina/administração & dosagem , Cloridrato de Atomoxetina/sangue , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/efeitos dos fármacos , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/efeitos dos fármacos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/tratamento farmacológico , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/efeitos dos fármacos
4.
Hum Brain Mapp ; 37(3): 1026-37, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26757216

RESUMO

Recent studies indicate that selective noradrenergic (atomoxetine) and serotonergic (citalopram) reuptake inhibitors may improve response inhibition in selected patients with Parkinson's disease, restoring behavioral performance and brain activity. We reassessed the behavioral efficacy of these drugs in a larger cohort and developed predictive models to identify patient responders. We used a double-blind randomized three-way crossover design to investigate stopping efficiency in 34 patients with idiopathic Parkinson's disease after 40 mg atomoxetine, 30 mg citalopram, or placebo. Diffusion-weighted and functional imaging measured microstructural properties and regional brain activations, respectively. We confirmed that Parkinson's disease impairs response inhibition. Overall, drug effects on response inhibition varied substantially across patients at both behavioral and brain activity levels. We therefore built binary classifiers with leave-one-out cross-validation (LOOCV) to predict patients' responses in terms of improved stopping efficiency. We identified two optimal models: (1) a "clinical" model that predicted the response of an individual patient with 77-79% accuracy for atomoxetine and citalopram, using clinically available information including age, cognitive status, and levodopa equivalent dose, and a simple diffusion-weighted imaging scan; and (2) a "mechanistic" model that explained the behavioral response with 85% accuracy for each drug, using drug-induced changes of brain activations in the striatum and presupplementary motor area from functional imaging. These data support growing evidence for the role of noradrenaline and serotonin in inhibitory control. Although noradrenergic and serotonergic drugs have highly variable effects in patients with Parkinson's disease, the individual patient's response to each drug can be predicted using a pattern of clinical and neuroimaging features.


Assuntos
Cloridrato de Atomoxetina/uso terapêutico , Citalopram/uso terapêutico , Inibição Psicológica , Imageamento por Ressonância Magnética/métodos , Doença de Parkinson/tratamento farmacológico , Psicotrópicos/uso terapêutico , Inibidores da Captação Adrenérgica/uso terapêutico , Idoso , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Encéfalo/fisiopatologia , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Doença de Parkinson/diagnóstico , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Prognóstico , Desempenho Psicomotor/efeitos dos fármacos , Desempenho Psicomotor/fisiologia , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico
5.
Mov Disord ; 31(8): 1163-72, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27091513

RESUMO

BACKGROUND: Parkinson's disease (PD) can cause impulsivity with premature responses, but there are several potential mechanisms. We proposed a distinction between poor decision-making and the distortion of temporal perception. Both effects may be present and interact, but with different clinical and pharmacological correlates. OBJECTIVES: This study assessed premature responding during time perception in PD. METHODS: In this study, 18 PD patients and 19 age-matched controls completed 2 temporal discrimination tasks (bisection and trisection) and a baseline reaction-time task. Timing sensitivity and decision-making processes were quantified by response and response time. An extended version of the modified difference model was used to examine the precision of time representation and the modulation of response time by stimulus ambiguity. RESULTS: In the bisection task, patients had a lower bisection point (P < .05) and reduced timing sensitivity when compared with controls (P < .001). In the trisection task, patients showed lower sensitivity in discriminating between short and medium standards (P < .05). The impairment in timing sensitivity correlated positively with patients' levodopa dose equivalent (P < .05). Critically, patients had disproportionately faster response times when compared with controls in more ambiguous conditions, and the degree of acceleration of response time increased with disease severity (P < .05). Computational modeling indicated that patients had poorer precision in time representation and stronger modulation of response time by task ambiguity, leading to smaller scaling of the decision latency (P < .05). CONCLUSIONS: These findings suggest that timing deficits in PD cannot be solely attributed to perceptual distortions, but are also associated with impulsive decision strategies that bias patients toward premature responses. © 2016 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Tomada de Decisões/fisiologia , Dopaminérgicos/farmacologia , Comportamento Impulsivo/fisiologia , Doença de Parkinson/fisiopatologia , Tempo de Reação/fisiologia , Percepção do Tempo/fisiologia , Idoso , Idoso de 80 Anos ou mais , Tomada de Decisões/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Comportamento Impulsivo/efeitos dos fármacos , Levodopa/farmacologia , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/tratamento farmacológico , Tempo de Reação/efeitos dos fármacos , Índice de Gravidade de Doença , Percepção do Tempo/efeitos dos fármacos
6.
Mov Disord ; 31(7): 1062-6, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26971528

RESUMO

BACKGROUND: Recent studies have suggested that melatonin-a hormone produced by the pineal gland under circadian control-contributes to PD-related sleep dysfunction. We hypothesized that degenerative changes to the neural structures controlling pineal function (especially the suprachiasmatic nuclei of the anterior hypothalamus) may be responsible for reduced melatonin output in these patients. We compared hypothalamic volumes in PD patients with matched controls and determined whether volume loss correlated with reduced melatonin output in the PD group. METHODS: A total of 12 PD patients and 12 matched controls underwent magnetic resonance imaging to determine hypothalamic volume. In addition, PD patients underwent 24-hour blood sampling in a controlled environment to determine serum melatonin concentrations using enzyme-linked immunosorbent assays. RESULTS: PD patients had significantly reduced hypothalamic gray matter volume when compared with matched controls. Melatonin levels were significantly associated with hypothalamic gray matter volume and disease severity in PD patients. CONCLUSION: Melatonin levels are associated with hypothalamic gray matter volume loss and disease severity in PD patients. This provides anatomical and physiological support for an intrinsic sleep and circadian phenotype in PD. © 2016 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Hipotálamo/patologia , Melatonina/sangue , Doença de Parkinson/sangue , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Idoso , Feminino , Humanos , Hipotálamo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico por imagem
7.
Brain ; 137(Pt 4): 1145-55, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24578545

RESUMO

Impulsivity is common in Parkinson's disease even in the absence of impulse control disorders. It is likely to be multifactorial, including a dopaminergic 'overdose' and structural changes in the frontostriatal circuits for motor control. In addition, we proposed that changes in serotonergic projections to the forebrain also contribute to response inhibition in Parkinson's disease, based on preclinical animal and human studies. We therefore examined whether the selective serotonin reuptake inhibitor citalopram improves response inhibition, in terms of both behaviour and the efficiency of underlying neural mechanisms. This multimodal magnetic resonance imaging study used a double-blind randomized placebo-controlled crossover design with an integrated Stop-Signal and NoGo paradigm. Twenty-one patients with idiopathic Parkinson's disease (46-76 years old, 11 male, Hoehn and Yahr stage 1.5-3) received 30 mg citalopram or placebo in addition to their usual dopaminergic medication in two separate sessions. Twenty matched healthy control subjects (54-74 years old, 12 male) were tested without medication. The effects of disease and drug on behavioural performance and regional brain activity were analysed using general linear models. In addition, anatomical connectivity was examined using diffusion tensor imaging and tract-based spatial statistics. We confirmed that Parkinson's disease caused impairment in response inhibition, with longer Stop-Signal Reaction Time and more NoGo errors under placebo compared with controls, without affecting Go reaction times. This was associated with less stop-specific activation in the right inferior frontal cortex, but no significant difference in NoGo-related activation. Although there was no beneficial main effect of citalopram, it reduced Stop-Signal Reaction Time and NoGo errors, and enhanced inferior frontal activation, in patients with relatively more severe disease (higher Unified Parkinson's Disease Rating Scale motor score). The behavioural effect correlated with the citalopram-induced enhancement of prefrontal activation and the strength of preserved structural connectivity between the frontal and striatal regions. In conclusion, the behavioural effect of citalopram on response inhibition depends on individual differences in prefrontal cortical activation and frontostriatal connectivity. The correlation between disease severity and the effect of citalopram on response inhibition may be due to the progressive loss of forebrain serotonergic projections. These results contribute to a broader understanding of the critical roles of serotonin in regulating cognitive and behavioural control, as well as new strategies for patient stratification in clinical trials of serotonergic treatments in Parkinson's disease.


Assuntos
Encéfalo/efeitos dos fármacos , Citalopram/farmacologia , Comportamento Impulsivo/tratamento farmacológico , Doença de Parkinson/complicações , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Idoso , Encéfalo/fisiopatologia , Estudos Cross-Over , Imagem de Tensor de Difusão , Método Duplo-Cego , Feminino , Humanos , Comportamento Impulsivo/etiologia , Comportamento Impulsivo/fisiopatologia , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia , Tempo de Reação/efeitos dos fármacos
8.
Brain ; 137(Pt 10): 2743-58, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25080285

RESUMO

Parkinson's disease is associated with multiple cognitive impairments and increased risk of dementia, but the extent of these deficits varies widely among patients. The ICICLE-PD study was established to define the characteristics and prevalence of cognitive change soon after diagnosis, in a representative cohort of patients, using a multimodal approach. Specifically, we tested the 'Dual Syndrome' hypothesis for cognitive impairment in Parkinson's disease, which distinguishes an executive syndrome (affecting the frontostriatal regions due to dopaminergic deficits) from a posterior cortical syndrome (affecting visuospatial, mnemonic and semantic functions related to Lewy body pathology and secondary cholinergic loss). An incident Parkinson's disease cohort (n = 168, median 8 months from diagnosis to participation) and matched control group (n = 85) were recruited to a neuroimaging study at two sites in the UK. All participants underwent clinical, neuropsychological and functional magnetic resonance imaging assessments. The three neuroimaging tasks (Tower of London, Spatial Rotations and Memory Encoding Tasks) were designed to probe executive, visuospatial and memory encoding domains, respectively. Patients were also genotyped for three polymorphisms associated with cognitive change in Parkinson's disease and related disorders: (i) rs4680 for COMT Val158Met polymorphism; (ii) rs9468 for MAPT H1 versus H2 haplotype; and (iii) rs429358 for APOE-ε2, 3, 4. We identified performance deficits in all three cognitive domains, which were associated with regionally specific changes in cortical activation. Task-specific regional activations in Parkinson's disease were linked with genetic variation: the rs4680 polymorphism modulated the effect of levodopa therapy on planning-related activations in the frontoparietal network; the MAPT haplotype modulated parietal activations associated with spatial rotations; and APOE allelic variation influenced the magnitude of activation associated with memory encoding. This study demonstrates that neurocognitive deficits are common even in recently diagnosed patients with Parkinson's disease, and that the associated regional brain activations are influenced by genotype. These data further support the dual syndrome hypothesis of cognitive change in Parkinson's disease. Longitudinal data will confirm the extent to which these early neurocognitive changes, and their genetic factors, influence the long-term risk of dementia in Parkinson's disease. The combination of genetics and functional neuroimaging provides a potentially useful method for stratification and identification of candidate markers, in future clinical trials against cognitive decline in Parkinson's disease.


Assuntos
Encéfalo/fisiopatologia , Cognição/fisiologia , Doença de Parkinson/genética , Doença de Parkinson/fisiopatologia , Idoso , Apolipoproteínas E/genética , Catecol O-Metiltransferase/genética , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/psicologia , Estudos de Coortes , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imaginação/fisiologia , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Memória/fisiologia , Pessoa de Meia-Idade , Proteínas Quinases Ativadas por Mitógeno/genética , Neuroimagem , Testes Neuropsicológicos , Desempenho Psicomotor/fisiologia , Rotação , Percepção Espacial/fisiologia , Proteínas tau/genética
9.
Biol Psychiatry ; 96(2): 101-113, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38141909

RESUMO

BACKGROUND: Deep brain stimulation (DBS) is a promising treatment option for treatment-refractory obsessive-compulsive disorder (OCD). Several stimulation targets have been used, mostly in and around the anterior limb of the internal capsule and ventral striatum. However, the precise target within this region remains a matter of debate. METHODS: Here, we retrospectively studied a multicenter cohort of 82 patients with OCD who underwent DBS of the ventral capsule/ventral striatum and mapped optimal stimulation sites in this region. RESULTS: DBS sweet-spot mapping performed on a discovery set of 58 patients revealed 2 optimal stimulation sites associated with improvements on the Yale-Brown Obsessive Compulsive Scale, one in the anterior limb of the internal capsule that overlapped with a previously identified OCD-DBS response tract and one in the region of the inferior thalamic peduncle and bed nucleus of the stria terminalis. Critically, the nucleus accumbens proper and anterior commissure were associated with beneficial but suboptimal clinical improvements. Moreover, overlap with the resulting sweet- and sour-spots significantly estimated variance in outcomes in an independent cohort of 22 patients from 2 additional DBS centers. Finally, beyond obsessive-compulsive symptoms, stimulation of the anterior site was associated with optimal outcomes for both depression and anxiety, while the posterior site was only associated with improvements in depression. CONCLUSIONS: Our results suggest how to refine targeting of DBS in OCD and may be helpful in guiding DBS programming in existing patients.


Assuntos
Estimulação Encefálica Profunda , Cápsula Interna , Transtorno Obsessivo-Compulsivo , Humanos , Transtorno Obsessivo-Compulsivo/terapia , Estimulação Encefálica Profunda/métodos , Masculino , Feminino , Adulto , Estudos Retrospectivos , Pessoa de Meia-Idade , Cápsula Interna/diagnóstico por imagem , Estriado Ventral/diagnóstico por imagem , Estriado Ventral/fisiopatologia , Resultado do Tratamento , Adulto Jovem
11.
Brain Struct Funct ; 228(3-4): 907-920, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36995433

RESUMO

The development and survival of dopaminergic neurons are influenced by the fibroblast growth factor (FGF) pathway. Anosmin-1 (A1) is an extracellular matrix protein that acts as a major regulator of this signaling pathway, controlling FGF diffusion, and receptor interaction and shuttling. In particular, previous work showed that A1 overexpression results in more dopaminergic neurons in the olfactory bulb. Prompted by those intriguing results, in this study, we investigated the effects of A1 overexpression on different populations of catecholaminergic neurons in the central (CNS) and the peripheral nervous systems (PNS). We found that A1 overexpression increases the number of dopaminergic substantia nigra pars compacta (SNpc) neurons and alters the striosome/matrix organization of the striatum. Interestingly, these numerical and morphological changes in the nigrostriatal pathway of A1-mice did not confer an altered susceptibility to experimental MPTP-parkinsonism with respect to wild-type controls. Moreover, the study of the effects of A1 overexpression was extended to different dopaminergic tissues associated with the PNS, detecting a significant reduction in the number of dopaminergic chemosensitive carotid body glomus cells in A1-mice. Overall, our work shows that A1 regulates the development and survival of dopaminergic neurons in different nuclei of the mammalian nervous system.


Assuntos
Doença de Parkinson , Camundongos , Animais , Doença de Parkinson/patologia , Substância Negra/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Sistema Nervoso Periférico/metabolismo , Sistema Nervoso Periférico/patologia , Camundongos Endogâmicos C57BL , Mamíferos
12.
Res Sq ; 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38045279

RESUMO

Deep-brain stimulation (DBS) is a potential novel treatment for memory dysfunction. Current attempts to enhance memory focus on stimulating human hippocampus or entorhinal cortex. However, an alternative strategy is to stimulate brain areas providing modulatory inputs to medial temporal memory-related structures, such as the nucleus accumbens (NAc), which is implicated in enhancing episodic memory encoding. Here, we show that NAc-DBS improves episodic and spatial memory in psychiatric patients. During stimulation, NAc-DBS increased the probability that infrequent (oddball) pictures would be subsequently recollected, relative to periods off stimulation. In a second experiment, NAc-DBS improved performance in a virtual path-integration task. An optimal electrode localization analysis revealed a locus spanning postero-medio-dorsal NAc and medial septum predictive of memory improvement across both tasks. Patient structural connectivity analyses, as well as NAc-DBS-evoked hemodynamic responses in a rat model, converge on a central role for NAc in a hippocampal-mesolimbic circuit regulating encoding into long-term memory. Thus, short-lived, phasic NAc electrical stimulation dynamically improved memory, establishing a critical on-line role for human NAc in episodic memory and providing an empirical basis for considering NAc-DBS in patients with loss of memory function.

13.
Front Aging Neurosci ; 14: 809972, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35431895

RESUMO

Background: Current treatments for Alzheimer's disease (AD) modulate global neurotransmission but are neither specific nor anatomically directed. Tailored stimulation of target nuclei will increase treatment efficacy while reducing side effects. We report the results of the first directional deep brain stimulation (dDBS) surgery and treatment of a patient with AD in an attempt to slow the progression of the disease in a woman with multi-domain, amnestic cognitive status. Methods: We aimed to assess the safety of dDBS in patients with AD using the fornix as stimulation target (primary objective) and the clinical impact of the stimulation (secondary objective). In a registered clinical trial, a female patient aged 81 years with a 2-year history of cognitive decline and diagnoses of AD underwent a bilateral dDBS surgery targeting the fornix. Stimulation parameters were set between 3.9 and 7.5 mA, 90 µs, 130 Hz for 24 months, controlling stimulation effects by 18F-fluoro-2-deoxy-D-glucose (18F-FDG) scans (baseline, 12 and 24 months), magnetoencephalography (MEG) and clinical/neuropsychological assessment (baseline, 6, 12, 18, and 24 months). Results: There were no important complications related to the procedure. In general terms, the patient showed cognitive fluctuations over the period, related to attention and executive function patterns, with no meaningful changes in any other cognitive functions, as is shown in the clinical dementia rating scale (CDR = 1) scores over the 24 months. Such stability in neuropsychological scores corresponds to the stability of the brain metabolic function, seen in PET scans. The MEG studies described low functional connectivity at baseline and a subsequent increase in the number of significant connections, mainly in the theta band, at 12 months. Conclusion: The dDBS stimulation in the fornix seems to be a safe treatment for patients in the first stage of AD. Effects on cognition seem to be mild to moderate during the first months of stimulation and return to baseline levels after 24 months, except for verbal fluency. Clinical Trial Registration: [https://clinicaltrials.gov/ct2/show/NCT03290274], identifier [NCT03290274].

14.
J Clin Med ; 10(15)2021 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-34362061

RESUMO

OBJECTIVE: The identification of a complementary test to confirm the diagnosis of FM. The diagnosis of fibromyalgia (FM) is based on clinical features, but there is still no consensus, so patients and clinicians might benefit from such a test. Recent findings showed that pain lies in neuronal bases (pain matrices) and, in the long term, chronic pain modifies the activity and dynamics of brain structures. Our hypothesis is that patients with FM present lower levels of brain activity and therefore less connectivity than controls. METHODS: We registered the resting state EEG of 23 patients with FM and compared them with 23 control subjects' resting state recordings from the PhysioBank database. We measured frequency, amplitude, and functional connectivity, and conducted source localization (sLORETA). ROC analysis was performed on the resulting data. RESULTS: We found significant differences in brain bioelectrical activity at rest in all analyzed bands between patients and controls, except for Delta. Subsequent source analysis provided connectivity values that depicted a distinct profile, with high discriminative capacity (between 91.3-100%) between the two groups. CONCLUSIONS: Patients with FM show a distinct neurophysiological pattern that fits with the clinical features of the disease.

15.
Front Cell Dev Biol ; 9: 621645, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34249901

RESUMO

Clinical trials of cell therapies that target stroke started at the beginning of this century and they have experienced a significant boost in recent years as a result of promising data from basic research studies. The increase in the information available has paved the way to carry out more innovative and varied human studies. Efforts have focused on the search for a safe and effective treatment to stimulate neuro-regeneration in the brain and to reduce the sequelae of stroke in patients. Therefore, this review aims to evaluate the clinical trials using cell therapy to treat stroke published to date and assess their limitations. From 2000 to date, most of the published clinical trials have focused on phases I or II, and the vast majority of them demonstrate that stem cells are essentially safe to use when administered by different routes, with transient and mild adverse events that do not generally have severe consequences for health. In general, there is considerable variation in the trials in terms of statistical design, sample size, the cells used, the routes of administration, and the functional assessments (both at baseline and follow-up), making it difficult to compare the studies. From this general description, possibly the experimental protocol is the main element to improve in future studies. Establishing an adequate experimental and statistical design will be essential to obtain favorable and reliable results when conducting phase III clinical trials. Thus, it is necessary to standardize the criteria used in these clinical trials in order to aid comparison. Shortly, cell therapy will be a key approach in the treatment of stroke if adequate and comprehensive levels of recovery are to be achieved.

16.
Front Neuroanat ; 15: 666938, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34040507

RESUMO

Pio del Rio-Hortega was not only the discoverer of the microglia and oligodendroglia but also possibly the most prolific mentor of all Santiago Ramon y Cajal's disciples (Nobel awardee in Physiology or Medicine 1906 and considered as the father of modern Neuroscience). Among Río-Hortega's mentees, three exceptional women are frequently forgotten, chronologically: Pio's niece Asunción Amo del Río who worked with Río-Hortega at Madrid, Paris, and Oxford; the distinguished British neuropathologist Dorothy Russell who also worked with Don Pío at Oxford; and Amanda Pellegrino de Iraldi, the last mentee in his career. Our present work analyzes the figures of these three women who were in contact and collaborated with Don Pío del Río-Hortega, describing the influences received and the impact on their careers and the History of Neuroscience. The present work completes the contribution of women neuroscientists who worked with Cajal and his main disciples of the Spanish Neurological School both in Spain (previous work) and in other countries (present work).

17.
Front Neurosci ; 14: 431, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32477053

RESUMO

Ischemic stroke (IS) is the leading cause of disability in the western world, assuming a high socio-economic cost. One of the most used strategies in the last decade has been biomaterials, which have been initially used with a structural support function. They have been perfected, different compounds have been combined, and they have been used together with cell therapy or controlled release chemical compounds. This double function has driven them as potential candidates for the chronic treatment of IS. In fact, the most developed are in different phases of clinical trial. In this review, we will show the ischemic scenario and address the most important criteria to achieve a successful neuroreparation from the point of view of biomaterials. The spontaneous processes that are activated and how to enhance them is one of the keys that contribute to the success of the therapeutic approach. In addition, the different routes of administration and how they affect the design of biomaterials are analyzed. Future perspectives show where this broad scientific field is heading, which advances every day with the help of technology and advanced therapies.

18.
J Neural Transm Suppl ; (73): 245-52, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20411782

RESUMO

Inflammatory responses have been proposed as important factors in dopaminergic neuro-degeneration in Parkinsonism. Increasing evidence suggests that the alteration of the glial microenvironment induced by neuronal degeneration could be deleterious to the remaining neurons. The activation of microglia/macrophages and reactive astrocytes may have a negative effect on the surrounding parenchyma, perpetuating the neurodegenerative process. However, this alteration may also go beyond the brain parenchyma and stimulate other inflammatory changes in other systems, inducing the release of proinflammatory cytokines and probably Acute Phase Proteins (APP) and Glucocorticoids (GC). In this work we review the latest advances in the field to provide a picture of the state of the art of studies of inflammatory responses and Parkinsonism, hopefully opening up new therapeutic perspectives for patients with Parkinson's disease.


Assuntos
Inflamação/etiologia , Transtornos Parkinsonianos/complicações , Transtornos Parkinsonianos/imunologia , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Glucocorticoides/metabolismo , História do Século XX , História do Século XXI , Humanos , Inflamação/patologia , Neuroglia/metabolismo , Transtornos Parkinsonianos/tratamento farmacológico , Transtornos Parkinsonianos/história , Transtornos Parkinsonianos/patologia
19.
Front Neuroanat ; 13: 72, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31379519

RESUMO

At the beginning of the 20th century, in view of the growing international recognition of Santiago Ramón y Cajal, the Spanish authorities took some important steps to support Cajal's scientific work. This recognition peaked in 1906, when Camillo Golgi and Santiago Ramón y Cajal shared the Nobel Prize in Physiology or Medicine. The Spanish government provided Cajal a state-of-the-art laboratory in Madrid to allow him to continue with his research and they funded salaries to pay his first tenured collaborators, the number of which increased further after the creation of the Junta para Ampliación de Estudios (JAE). The JAE was an organism set up to help promising researchers develop their careers in different ways, thereby contributing to the development of science in Spain. Although largely forgotten or relatively unknown, there has been a recent revival in the recognition of the school that developed around Cajal, collectively referred to as the Spanish Neurological School (or colloquially, as the Cajal School or School of Madrid). Almost all Cajal's collaborators were men, although a limited number of female scientists spent part of their careers at the heart of the Cajal School. Here we discuss these women and their work in the laboratory in Madrid. We have tracked the careers of Laura Forster (from Australia/United Kingdom), Manuela Serra, María Soledad Ruiz-Capillas and María Luisa Herreros (all Spanish), through their scientific publications, both in the journal founded by Cajal and elsewhere, and from other documentary sources. To complete the picture, we also outline the careers of other secondary figures that contributed to the production and running of Cajal's laboratory in Madrid. We show here that the dawn of Spanish neuroscience included a number of contributions from female researchers who to date, have received little recognition.

20.
Neurosurgery ; 85(2): E294-E303, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30690487

RESUMO

BACKGROUND: Although deep brain stimulation (DBS) of the dorsolateral subthalamic nucleus (STN) is a well-established surgical treatment for patients with Parkinson disease (PD), there is still controversy about the relationship between the functional segregation of the STN and clinical outcomes. OBJECTIVE: To correlate motor and neuropsychological (NPS) outcomes with the overlap between the volume of activated tissue (VAT) and the tractography-defined regions within the STN. METHODS: Retrospective study evaluating 13 patients with PD treated with STN-DBS. With the aid of tractography, the STN was segmented into 4 regions: smaSTN (supplementary motor area STN), m1STN (primary motor area STN), mSTN (the sum of the m1STN and the smaSTN segments), and nmSTN (non-motor STN). We computed the overlap coefficients between these STN regions and the patient-specific VAT. The VAT outside of the STN was also calculated. These coefficients were then correlated with motor (Unified Parkinson's Disease Rating Scale, UPDRS III) and NPS outcomes. RESULTS: Stimulation of the mSTN segment was significantly correlated with UPDRS III and bradykinesia improvement. Stimulation of the smaSTN segment, but not the m1STN one, had a positive correlation with bradykinesia improvement. Stimulation of the nmSTN segment was negatively correlated with the improvement in rigidity. Stimulation outside of the STN was correlated with some beneficial NPS effects. CONCLUSION: Stimulation of the tractography-defined motor STN, mainly the smaSTN segment, is positively correlated with motor outcomes, whereas stimulation of the nmSTN is correlated with poor motor outcomes. Further validation of these results might help individualize and optimize targets prior to STN-DBS.


Assuntos
Estimulação Encefálica Profunda/métodos , Doença de Parkinson/terapia , Núcleo Subtalâmico/fisiopatologia , Idoso , Feminino , Marcadores Fiduciais , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Motor/fisiopatologia , Doença de Parkinson/diagnóstico por imagem , Estudos Retrospectivos , Núcleo Subtalâmico/diagnóstico por imagem , Resultado do Tratamento
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