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1.
J Integr Neurosci ; 22(2): 30, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36992596

RESUMO

BACKGROUND: Music is considered a valuable method for stimulating patients with disorders of consciousness (DOC) by enhancing their awareness and arousal. Although biographical music and auditory relative stimulation has been shown, responses to other types of music has not yet been addressed. The purpose of this study was to assess the brain responses in critically ill patients under sedo-analgesia to music that is highly different in features. METHODS: We measured the individual responses to three types of music: classical (ClassM, Mozart), dodecaphonic (DodecM, Schönberg), and heavy metal (HeavyM, Volbeat) in six critically ill patients (one male, five female, all between 53 and 82 years old) with primary brain pathology under sedo-analgesia. We analyzed the changes in each patient's electroencephalogram (EEG) band composition (delta, 1-4 Hz, theta 4-8 Hz, alpha 8-13 Hz, and beta 13-30 Hz) and synchronization throughout the scalp. RESULTS: In spite of the heterogeneity in the responses, ClassM did not change the basal activity, although there was a tendency toward a decrease in brain activity. DodecM increased the alpha and beta bands from the right hemisphere. However, HeavyM increased the delta and theta bands from the frontal lobes and the alpha and beta bands from most of the scalp. No significant changes in synchronization were observed. CONCLUSIONS: Different types of music induce heterogeneous responses in the brain, suggesting that music interventions could affect the brain state of patients. HeavyM induced the greatest changes in brain responses, whereas ClassM showed a tendency to reduce brain activity. The result of this study opens the possibility of using different types of music as tools during the rehabilitation process.


Assuntos
Analgesia , Música , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Projetos Piloto , Estado Terminal , Eletroencefalografia/métodos , Estimulação Acústica/métodos , Dor , Unidades de Terapia Intensiva , Percepção Auditiva/fisiologia
2.
J Integr Neurosci ; 22(1): 17, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36722245

RESUMO

BACKGROUND: Cortico-cortical evoked potentials (CCEPs) have been used to map the frontal (FLA) and parietal (PLA) cortical regions related to language function. However, they have usually been employed as a complementary method during sleep-awake surgery. METHODS: Five male and two female patients received surgery for tumors located near language areas. Six patients received general anesthesia and the sleep-awake method was used for patients with tumors located near the cortical language areas. We performed motor and somatosensory mapping with CCEPs to identify language areas and we monitored responses during surgery based on the mapping results. Electrocorticography was performed throughout the surgery. Single pulses of 1 ms duration at 5-20 mA were delivered by direct cortical stimulation using one grid at one region (e.g., FLA) and then recording using a second gird at another area (i.e., PLA). Next, reversed stimulation (from PLA to FLA) was performed. The charge density for electrical stimulation was computed. Sensibility, specificity, predictive positive values, and predicted negative values were also computed for warning alterations of CCEPs. RESULTS: Gross tumor resection was achieved in four cases. The first postsurgical day showed language alterations in three patients, but one year later six patients remained asymptomatic and one patient showed the same symptomatology as previously. Seizures were observed in two patients that were easily jugulated. CCEPs predicted warning events with high sensibility and specificity. Postsurgical language deficits were mostly transitory. Although the latency between frontal and parietal regions showed symmetry, the amplitude and the relationship between amplitude and latency were different for FLA than for PLA. The charge density elicited by CCEPs ranged from 442 to 1768 µC/cm2. CONCLUSIONS: CCEPs have proven to be a reliable neurophysiological technique for mapping and monitoring the regions associated with language function in a small group of anesthetized patients. The high correlation between warning events and postsurgical outcomes suggested a high sensitivity and specificity and CCEPs can be used systematically in patients under general anesthesia. Nevertheless, the small number of studied patients suggests considering these results cautiously.


Assuntos
Neoplasias Encefálicas , Humanos , Feminino , Masculino , Neoplasias Encefálicas/cirurgia , Vigília , Encéfalo , Idioma , Poliésteres
3.
Sensors (Basel) ; 21(20)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34696052

RESUMO

Self-localization based on passive RFID-based has many potential applications. One of the main challenges it faces is the suppression of the reflected signals from unwanted objects (i.e., clutter). Typically, the clutter echoes are much stronger than the backscattered signals of the passive tag landmarks used in such scenarios. Therefore, successful tag detection can be very challenging. We consider two types of tags, namely low-Q and high-Q tags. The high-Q tag features a sparse frequency response, whereas the low-Q tag presents a broad frequency response. Further, the clutter usually showcases a short-lived response. In this work, we propose an iterative algorithm based on a low-rank plus sparse recovery approach (RPCA) to mitigate clutter and retrieve the landmark response. In addition to that, we compare the proposed approach with the well-known time-gating technique. It turns out that RPCA outperforms significantly time-gating for low-Q tags, achieving clutter suppression and tag identification when clutter encroaches on the time-gating window span, whereas it also increases the backscattered power at resonance by approximately 12 dB at 80 cm for high-Q tags. Altogether, RPCA seems a promising approach to improve the identification of passive indoor self-localization tag landmarks.

4.
J Sports Sci ; 37(12): 1403-1410, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30583709

RESUMO

Classification is a defining feature of Para-sport, and sports-specific classification systems determined through multidisciplinary scientific research are required, i.e., evidence-based and focused on the relationship between the impairment and the key performance determinants. Data envelopment analysis (DEA) was applied as a classification tool using a directional distance function (DDF) model. The aim of the study was to test the DEA as a possible classification tool in cerebral palsy football. We analyse the performance of 56 international para-footballers with hypertonia, ataxia or athetosis, who completed a 20-test battery with DEA models. Five of the tests are included in the model (change of direction: Illinois agility test; jumping: standing broad jump, four bounds for distance, and triple hop with the non-dominant leg; 10-m sprint/acceleration; and ball dribbling, both in a straight line and following a trajectory), showing that players with less impairment exhibit the highest efficiency. This outcome suggests that DEA models might be feasible for detecting and discriminating the performance and magnitude of impairment in cerebral palsy football, with an objective ranking of the athletes in relation to different physical performance tests. This study also provides reference scores for decision-making during classification and guidance for further research in team Paralympic sports.


Assuntos
Ataxia/diagnóstico , Atletas/classificação , Tomada de Decisões , Futebol , Esportes para Pessoas com Deficiência , Adolescente , Adulto , Desempenho Atlético , Pessoas com Deficiência , Teste de Esforço , Humanos , Modelos Teóricos , Adulto Jovem
5.
Stereotact Funct Neurosurg ; 95(3): 137-141, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28433987

RESUMO

BACKGROUND: Although there are few reports of radiofrequency lesions performed through deep brain stimulation (DBS) electrodes in patients with movement disorders, experience with this method is scarce. METHODS: We present 2 patients who had been previously treated with DBS of subthalamic nuclei (STN) and the ventral intermediate (VIM) nucleus of the thalamus for Parkinson's disease and essential tremor, respectively, and underwent a radiofrequency lesion through their DBS electrodes after developing a hardware infection. The authors conduct a review of the literature regarding this method. RESULTS: Both patients had a good clinical outcome after 20 and 8 months, respectively, as assessed by a reduction in Fahn-Tolosa-Marin Scale and Unified Parkinson's Disease Rating Scale scores. The second patient underwent a second DBS system implantation surgery after his radiofrequency treatment to optimize his management, achieving optimal clinical control with lower current and drug requirements than before the radiofrequency intervention. No adverse effects were observed. CONCLUSIONS: Radiofrequency lesions through DBS electrodes allow the creation of small and localized lesions. Its effectiveness and low-risk profile, in addition to its low cost, make this procedure suitable and a possible alternative in the therapeutic repertoire for the surgical treatment of movement disorders.


Assuntos
Ablação por Cateter , Estimulação Encefálica Profunda , Tremor Essencial/cirurgia , Doença de Parkinson/cirurgia , Núcleo Subtalâmico/cirurgia , Núcleos Ventrais do Tálamo/cirurgia , Idoso , Ablação por Cateter/instrumentação , Estimulação Encefálica Profunda/instrumentação , Eletrodos Implantados , Humanos , Pessoa de Meia-Idade
6.
Acta Neurochir (Wien) ; 159(1): 131-136, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27878616

RESUMO

BACKGROUND: Vagal nerve stimulation (VNS) response is not immediate. A progressive decline in seizure frequency is usually found during a period of 12-18 months after implantation. During this time, the patient's medication is usually modified, which can create doubts about whether their clinical improvement is due to medication changes or to VNS itself. Our goal is to compare two groups of patients treated with VNS, with and without changes in their medication. METHODS: We prospectively analyze 85 patients who were treated with VNS in our hospital between 2005 and 2014. In 43 patients, changes in the antiepileptic drugs (EAD) were not allowed during the postoperative follow-up and they were compared with 42 patients who were left at the option of neurologist make changes in medication. We analyzed the clinical situation at 18 months and compared the two groups. RESULTS: Overall, 54.1% of patients had a reduction in seizures of 50% or higher (responders). In the group with no changes in medication, responders reached 63%, while in the group in which changes in medication were allowed, 45.2% were responders. Between responders and non-responders, there were no statistical differences in type of epilepsy, frequency, previous surgery, or intensity of stimulation. CONCLUSIONS: We did not find a statistical difference in seizure frequency reduction between patients with or without changes in medication during their follow-up, so changes in medication did not improve the outcome. Furthermore, the absence of changes in AED can help to optimize the parameters of the stimulator in order to improve its effectiveness.


Assuntos
Anticonvulsivantes/farmacologia , Epilepsia Resistente a Medicamentos/terapia , Avaliação de Resultados em Cuidados de Saúde , Estimulação do Nervo Vago/métodos , Adolescente , Adulto , Idoso , Anticonvulsivantes/administração & dosagem , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
J Environ Manage ; 196: 148-160, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28284132

RESUMO

Over the last twenty years an increasing number of studies have relied on the standard definition of the Malmquist-Luenberger index proposed by Chung et al. (1997) [J. Environ. Manage., 51, 229-240], to assess environmental sensitive productivity change. While recent contributions have shown that it suffers from relevant drawbacks related to inconsistencies and infeasibilities, no one has studied systematically the performance of the original model, and to what extent the existing results are unreliable. We introduce the optimization techniques that implement the model by Aparicio et al. (2013) [Eur. J. Oper. Res., 229(3), 738-742] solving these problems, and using a country level database on air pollutants systematically compare the results obtained with both approaches. Over the 1995-2007 period environmental productivity stagnation prevails across developed and developing countries, and while increasing technical progress takes place in the later years, it is offset by declining efficiency. Results show also that inconsistencies and infeasibilities in the original model are increasing in the number of undesirable outputs included, reaching remarkable values that seriously question the reliability of results, and compromise any environmental policy recommendation based on them.


Assuntos
Poluentes Atmosféricos , Eficiência , Meio Ambiente , Reprodutibilidade dos Testes
8.
J Environ Qual ; 44(5): 1579-88, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26436275

RESUMO

Sewage sludges from urban wastewater treatment plants are often used to remediate degraded soils. However, the benefits of their use in metal-polluted soils remain unclear and need to be assessed in terms of factors besides soil fertility. This study examines the use of thermal-dried sewage sludge (TDS) as an amendment for heavy metal-polluted soil in terms of its effects on soil chemical properties, leachate composition, and the growth of native plant communities. To assess the response of the soil and its plant community to an increase in metal mobilization, the effects of TDS amendment were compared with those of the addition of a chelating agent (ethylenediaminetetraacetic acid [EDTA]). The experimental design was based on a real-case scenario in which soils from of an abandoned mine site were used in a greenhouse bioassay. Two doses of TDS and EDTA were applied to a soil containing high Pb, Zn, Cu, and Cd levels (4925, 5675, 404, and 25 mg kg, respectively). Soil pH was 6.4, and its organic matter content was 5.53%. The factors examined after soil amendment were soil fertility and heavy metal contents, leachate element losses, the plant community arising from the seed bank (plant cover, species richness and biodiversity, above/below ground biomass), and phytotoxic effects (chemical contents of abundant species). Thermal-dried sewage sludge emerged as a good phytostabilizer of Pb, Zn, Cu, and Cd given its capacity to reduce the plant uptake of metals and achieve rapid plant cover. This amendment also enhanced the retention of other elements in the plant root system and overall showed a better capacity to remediate soils polluted with several heavy metals. The addition of EDTA led to plant productivity losses and nutritional imbalances because it increased the mobility of several elements in the soil and its leachates.

9.
Int J Phytoremediation ; 17(10): 988-98, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25789983

RESUMO

The soils of many abandoned mine sites in the central region of Spain are heavily polluted with a number of different metals. Having frequently found Agrostis castellana growing at these old mine sites, this study was designed to assess its remediation capacity for this type of setting. In an initial field study, plant specimens were collected from 4 abandoned mine sites to determine pollutant concentrations in their roots and shoots. This was followed by a 4-year bioassay in a controlled environment in which soils collected from the mines were used to set up microcosms. Maximum root concentrations of the most polluting elements present in the bioassay were 3625 mg kg(-1) Zn, 2793 mg kg(-1) Cu, 13042 mg kg(-1) Pb, 49 mg kg(-1) Cd and 957 mg kg(-1) As. These concentrations represent root bioaccumulation indices of over 1 and usually >2. In contrast, indices of transfer to above-ground phytomass were always < 1, indicating this species is a good candidate for use as a phytostabilizer. However, the high metal concentrations that could reach the above-ground mass of this plant determines a need for close monitoring and avoiding the use of areas under restoration for hunting or grazing.


Assuntos
Agrostis/metabolismo , Metais Pesados/metabolismo , Poluentes do Solo/metabolismo , Agrostis/crescimento & desenvolvimento , Biodegradação Ambiental , Mineração , Raízes de Plantas/química , Espanha
10.
Cereb Cortex ; 23(5): 1240-6, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22581850

RESUMO

Brain function is recognized to rely on neuronal activity and signaling processes between neurons, whereas astrocytes are generally considered to play supportive roles for proper neuronal function. However, accumulating evidence indicates that astrocytes sense and control neuronal and synaptic activity, indicating that neuron and astrocytes reciprocally communicate. While this evidence has been obtained in experimental animal models, whether this bidirectional signaling between astrocytes and neurons occurs in human brain remains unknown. We have investigated the existence of astrocyte-neuron communication in human brain tissue, using electrophysiological and Ca(2+) imaging techniques in slices of the cortex and hippocampus obtained from biopsies from epileptic patients. Cortical and hippocampal human astrocytes displayed spontaneous Ca(2+) elevations that were independent of neuronal activity. Local application of transmitter receptor agonists or nerve electrical stimulation transiently elevated Ca(2+) in astrocytes, indicating that human astrocytes detect synaptic activity and respond to synaptically released neurotransmitters, suggesting the existence of neuron-to-astrocyte communication in human brain tissue. Electrophysiological recordings in neurons revealed the presence of slow inward currents (SICs) mediated by NMDA receptor activation. The frequency of SICs increased after local application of ATP that elevated astrocyte Ca(2+). Therefore, human astrocytes are able to release the gliotransmitter glutamate, which affect neuronal excitability through activation of NMDA receptors in neurons. These results reveal the existence of reciprocal signaling between neurons and astrocytes in human brain tissue, indicating that astrocytes are relevant in human neurophysiology and are involved in human brain function.


Assuntos
Astrócitos/fisiologia , Encéfalo/fisiologia , Sinalização do Cálcio/fisiologia , Cálcio/metabolismo , Comunicação Celular/fisiologia , Neurônios/fisiologia , Adulto , Células Cultivadas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Epilepsia ; 54(10): 1823-33, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24032641

RESUMO

PURPOSE: Deep brain stimulation (DBS) of the thalamus is an emerging surgical option for people with medically refractory epilepsy that is not suitable for resective surgery, or in whom surgery has failed. Our main aim was to evaluate the efficacy of bilateral centromedian thalamic nucleus (CMN) DBS for seizure control in generalized epilepsy and frontal lobe epilepsy with a two-center, single-blind, controlled trial. METHODS: Participants were adults with refractory generalized or frontal lobe epilepsy. Seizure diaries were kept by patients/carers prospectively from enrollment. The baseline preimplantation period was followed by a control period consisting of a blind stimulation-OFF phase of at least 3 months, a 3-month blind stimulation-ON phase, and a 6-month unblinded stimulation-ON phase. The control period was followed by an unblinded long-term extension phase with stimulation-ON in those patients in whom stimulation was thought to be effective. KEY FINDINGS: Eleven patients were recruited at King's College Hospital (London, United Kingdom United Kingdom) and at University Hospital La Princesa (Madrid, Spain). Among the five patients with frontal lobe epilepsy, only one patient had >50% improvement in seizure frequency during the blind period. In the long-term extension phase, two patients with frontal lobe epilepsy had >50% improvement in seizure frequency. All six patients with generalized epilepsy had >50% improvement in seizure frequency during the blind period. In the long-term extension phase, five of the six patients showed >50% improvement in the frequency of major seizures (one became seizure free, one had >99% improvement, and three had 60-95% reduction in seizure frequency). Among patients with generalized epilepsy, the DBS implantation itself appears to be effective, as two patients remained seizure free during 12 and 50 months with DBS OFF, and the remaining four had 50-91% improvement in the initial 3 months with DBS OFF. SIGNIFICANCE: DBS implantation and stimulation of the CMN appears to be a safe and efficacious treatment, particularly in patients with refractory generalized epilepsy. CMN stimulation was not as effective in frontal lobe epilepsy, which requires further studies. DBS of the CMN should be considered as a treatment option, particularly in patients with refractory generalized epilepsy syndromes.


Assuntos
Estimulação Encefálica Profunda/métodos , Epilepsia do Lobo Frontal/terapia , Epilepsia Generalizada/terapia , Núcleos Intralaminares do Tálamo/fisiopatologia , Adolescente , Adulto , Epilepsia do Lobo Frontal/fisiopatologia , Epilepsia Generalizada/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Resultado do Tratamento , Adulto Jovem
12.
Acta Neurochir (Wien) ; 155(12): 2201-13, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24072425

RESUMO

BACKGROUND: Fluorescence-guided resection (FGR) using 5-aminolevulinic acid (5-ALA) exhibits a potential risk of permanent neurological deficits that can be minimized using intraoperative neurophysiological monitoring (IONM). We assessed the role of IONM in FGR surgery in patients harboring tumors in or near eloquent areas. METHODS: IONM and FGR surgeries were performed on 34 patients (49.8 ± 2.4 years) harbored malignant primary gliomas near eloquent cortical areas or semioval center. Different combinations of neurophysiological techniques were used depending on each patient. RESULTS: Gross total resection (GTR) was achieved in 66.7 % of the patients, mean 90.4 ± 3.7 % without neurological deficits. Resection in four patients was stopped by the occurrence of severe warning criteria despite the presence of fluorescence. Hemispheric transcranial electrical stimulation was safe and confident even in cortical surgery. Notably, a significant percentage of patients exhibited clinical improvement after the surgery. One week after surgery, only one patient worsened, and seven patients improved. At 3 months, 27.8 % of the patients improved, and the other patients maintained a similar status to their pre-surgery condition. Warning common criteria (amplitude reduction and/or latency increase) appeared in 68.2 and 50.0 % of patients during cortical or semioval surgery, respectively, with neither a false-negative nor a false-positive clinical outcome. Although 5-ALA exhibits phototoxicity, VEP did not induce any secondary effects in the visual system, including eyelids. CONCLUSIONS: IONM can be helpful during surgery to maximize the tumor resection, meanwhile help to avoid neurological deficits and, therefore, to improve the quality of life of these patients.


Assuntos
Neoplasias Encefálicas/patologia , Glioma/patologia , Monitorização Neurofisiológica Intraoperatória , Adulto , Idoso , Ácido Aminolevulínico , Mapeamento Encefálico/métodos , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/cirurgia , Feminino , Glioma/diagnóstico , Glioma/cirurgia , Humanos , Monitorização Neurofisiológica Intraoperatória/métodos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
13.
Brain Sci ; 13(2)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36831710

RESUMO

We used numerical methods to define the normative structure of resting-state EEG (rsEEG) in a pilot study of 37 healthy subjects (10-74 years old), using a double-banana bipolar montage. Artifact-free 120-200 s epoch lengths were visually identified and divided into 1 s windows with a 10% overlap. Differential channels were grouped by frontal, parieto-occipital, and temporal lobes. For every channel, the power spectrum was calculated and used to compute the area for delta (0-4 Hz), theta (4-8 Hz), alpha (8-13 Hz), and beta (13-30 Hz) bands and was log-transformed. Furthermore, Shannon's spectral entropy (SSE) and coherence by bands were computed. Finally, we also calculated the main frequency and amplitude of the posterior dominant rhythm. According to the age-dependent distribution of the bands, we divided the patients in the following three groups: younger than 20; between 21 and 50; and older than 51 years old. The distribution of bands and coherence was different for the three groups depending on the brain lobes. We described the normative equations for the three age groups and for every brain lobe. We showed the feasibility of a normative structure of rsEEG picked up with a double-banana montage.

14.
Brain Sci ; 13(6)2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37371421

RESUMO

Science and philosophy have tried to understand the origin of emotions for centuries. However, only in the last 150 years have we started to try to understand them in a neuroscientific scope. Emotions include physiological changes involving different systems, such as the endocrine or the musculoskeletal, but they also cause a conscious experience of those changes that are embedded in memory. In addition to the cortico-striato-thalamo-cortical circuit, which is the most important of the basal ganglia, the limbic system and prefrontal circuit are primarily involved in the process of emotion perceptions, thoughts, and memories. The purpose of this review is to describe the anatomy and physiology of the different brain structures involved in circuits that underlie emotions and behaviour, underlying the symptoms of certain psychiatric pathologies. These circuits are targeted during deep brain stimulation (DBS) and knowledge of them is mandatory to understand the clinical-physiological implications for the treatment. We summarize the main outcomes of DBS treatment in several psychiatric illness such as obsessive compulsive disorder, refractory depression, erethism and other conditions, aiming to understand the rationale for selecting these neural systems as targets for DBS.

15.
Front Biosci (Landmark Ed) ; 27(5): 155, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35638422

RESUMO

BACKGROUND: We obtained microelectrode recordings from four patients with intractable aggressivity who underwent surgery at posteromedial hypothalamus under general anaesthesia. We described two general types of extracellular action potentials (EAPs): typical/canonical and atypical. METHODS: We analysed 337 units and 67 traces, which were characterized by the mean action potential (mAP). For the first phase, depolarization and repolarization, we computed amplitudes (VFP, VDep and VRep) and durations (dFP, dDep and dRep), maximum and minimum values of the first derivative (dVmax, dVmin), and amplitude and duration ratios. RESULTS: Most of the canonical mAPs were positive (81.1%). EAPs with atypical mean action potentials (amAPs) were recorded in 42/337 cases. Only 35.6% of mAPs showed 2 phases. We identified the following types: N1P1N2 (38.3%), P1N1 (35.9%), amAP (12.5%), P1P2N1 (12.2%), N1P1 (4.7%), P1N1P2 (4.1%) and N1N2P1 (3.2%). We can define the properties of canonical forms as those units with (i) at least two opposite phases; (ii) VDep∈[1.2,2.7]×|VRep| and strongly related by this function VRep=-0.56⁢(±0.01)⁢VDep-1.83⁢(±0.79); (iii) a very strong relationship between dVmax and dVmin, given by the equation d⁢Vmin=-0.91⁢(±0.03)⁢d⁢Vmax-0.37⁢(±0.12), both of which were included in the depolarization phase; (iv) related with VDep by the equation d⁢Vmax=0.08⁢(±0.001)⁢VDep-0.28⁢(±0.14); and (v) dDep⁢~⁢0.38⁢dRep. However, the first phase does not pertain to the same dynamic process responsible for depolarization and repolarization. CONCLUSIONS: Atypical units are described here for the first time and are true EAPs that differ strikingly from canonical forms. To date, they have been observed only in the hypothalamus, but future research is needed to assess their existence in other brain structures.


Assuntos
Hipotálamo , Potenciais de Ação/fisiologia , Humanos
16.
Brain Sci ; 12(1)2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-35053786

RESUMO

Deep brain stimulation (DBS) requires a precise localization, which is especially difficult at the hypothalamus, because it is usually performed in anesthetized patients. We aimed to characterize the neurophysiological properties posteromedial hypothalamus (PMH), identified by the best neurophysiological response to electrical stimulation. We obtained microelectrode recordings from four patients with intractable aggressivity operated under general anesthesia. We pooled data from 1.5 mm at PMH, 1.5 mm upper (uPMH) and 1.5 mm lower (lPMH). We analyzed 178 units, characterized by the mean action potential (mAP). Only 11% were negative. We identified the next types of units: P1N1 (30.9%), N1P1N2 (29.8%), P1P2N1 (16.3%), N1P1 and N1N2P1 (6.2%) and P1N1P2 (5.0%). Besides, atypical action potentials (amAP) were recorded in 11.8%. PMH was highly different in cell composition from uPMH and lPMH, exhibiting also a higher percentage of amAP. Different kinds of cells shared similar features for the three hypothalamic regions. Although features for discharge pattern did not show region specificity, the probability mass function of inter-spike interval were different for all the three regions. Comparison of the same kind of mAP with thalamic neurons previously published demonstrate that most of cells are different for derivatives, amplitude and/or duration of repolarization and depolarization phases and also for the first phase, demonstrating a highly specificity for both brain centers. Therefore, the different properties described for PMH can be used to positively refine targeting, even under general anesthesia. Besides, we describe by first time the presence of atypical extracellular action potentials.

17.
J Clin Med ; 10(14)2021 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-34300231

RESUMO

BACKGROUND: Tarsal tunnel syndrome (TTS) is one of the most common entrapment syndromes. Although diagnosis is supported by imaging tests, it has so far been based on clinical findings. Neurophysiological tests are not effective for providing an accurate diagnosis. The objective of this study was to analyze the efficacy of the ultrasound-guided near-nerve needle sensory technique (USG-NNNS) for the diagnosis of TTS Methods: The study population comprised 40 patients referred for a neurophysiological study owing to clinical suspicion of TTS. Routine neurophysiological tests were performed and compared with the results of USG-NNNS. RESULTS: The diagnosis of TTS was achieved in 90% of cases. We found significant differences between lateral plantar sensory recordings with surface electrodes and USG-NNNS techniques for amplitude, nerve conduction velocity (NCV), and duration. As for the medial plantar sensory recordings, differences were found only for duration. No responses were obtained with surface electrode studies in 64.8% of cases. In addition, we observed normal sensory NCV with surface electrodes in 20 patients, although this decreased when the NNNS technique was used. CONCLUSIONS: This is the first report of the efficacy of the USG-NNNS technique for confirming the diagnosis of TTS.

18.
Neurotherapeutics ; 18(3): 1665-1677, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33904113

RESUMO

Deep brain stimulation (DBS), specifically thalamic DBS, has achieved promising results to reduce seizure severity and frequency in pharmacoresistant epilepsies, thereby establishing it for clinical use. The mechanisms of action are, however, still unknown. We evidenced the brain networks directly modulated by centromedian (CM) nucleus-DBS and responsible for clinical outcomes in a cohort of patients uniquely diagnosed with generalized pharmacoresistant epilepsy. Preoperative imaging and long-term (2-11 years) clinical data from ten generalized pharmacoresistant epilepsy patients (mean age at surgery = 30.8 ± 5.9 years, 4 female) were evaluated. Volume of tissue activated (VTA) was included as seeds to reconstruct the targeted network to thalamic DBS from diffusion and functional imaging data. CM-DBS clinical outcome improvement (> 50%) appeared in 80% of patients and was tightly related to VTAs interconnected with a reticular system network encompassing sensorimotor and supplementary motor cortices, together with cerebellum/brainstem. Despite methodological differences, both structural and functional connectomes revealed the same targeted network. Our results demonstrate that CM-DBS outcome in generalized pharmacoresistant epilepsy is highly dependent on the individual connectivity profile, involving the cerebello-thalamo-cortical circuits. The proposed framework could be implemented in future studies to refine stereotactic implantation or the parameters for individualized neuromodulation.


Assuntos
Estimulação Encefálica Profunda/tendências , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/terapia , Núcleos Intralaminares do Tálamo/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Adulto , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética/tendências , Masculino , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
19.
Oper Neurosurg (Hagerstown) ; 21(3): 165-171, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34017998

RESUMO

BACKGROUND AND IMPORTANCE: Deep brain stimulation of the posteromedial hypothalamus (PMH DBS) appears to be an effective treatment for drug-resistant aggressiveness. Weaver syndrome (WS) is a rare genetic disorder in which patients develop some degree of intellectual disability and rarely severe behavioral alterations that may benefit from this procedure. CLINICAL PRESENTATION: We present the case of a 26-yr-old man diagnosed with WS presenting with uncontrollable self and heteroaggressiveness and disruptive behavior refractory to pharmacological treatment and under severe physical and mechanical restraining measures. The patient was successfully treated with bilateral PMH DBS resulting in affective improvement, greater tolerance for signs of affection, regularization in his sleep pattern and appetite disturbances at 12-mo follow-up. A detailed description and video of the procedure are presented, and a review of the clinical characteristics of WS and the utility and benefits of PMH DBS for refractory aggressiveness are reviewed. CONCLUSION: To our knowledge, this is the first case of refractory aggressiveness described in WS as well as the first patient with WS successfully treated with PMH DBS.


Assuntos
Anormalidades Craniofaciais , Estimulação Encefálica Profunda , Anormalidades Múltiplas , Agressão , Hipotireoidismo Congênito , Deformidades Congênitas da Mão , Humanos , Hipotálamo , Masculino
20.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 6247-6250, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892541

RESUMO

Recent estimations state that the absolute number of strokes will increase in the future. For this reason, novel rehabilitation therapies, such as robot-assisted therapy, are essential to speed up patient recovery. This paper describes the design, development, and control aspects of a light-exoskeleton addressing forearm and wrist motions using one actuator. Besides, usability pilot study results are presented.


Assuntos
Exoesqueleto Energizado , Reabilitação do Acidente Vascular Cerebral , Desenho de Equipamento , Antebraço , Humanos , Projetos Piloto , Punho
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