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1.
J Neural Eng ; 21(1)2024 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-38211344

RESUMEN

Deep brain stimulation (DBS) using Medtronic's Percept™ PC implantable pulse generator is FDA-approved for treating Parkinson's disease (PD), essential tremor, dystonia, obsessive compulsive disorder, and epilepsy. Percept™ PC enables simultaneous recording of neural signals from the same lead used for stimulation. Many Percept™ PC sensing features were built with PD patients in mind, but these features are potentially useful to refine therapies for many different disease processes. When starting our ongoing epilepsy research study, we found it difficult to find detailed descriptions about these features and have compiled information from multiple sources to understand it as a tool, particularly for use in patients other than those with PD. Here we provide a tutorial for scientists and physicians interested in using Percept™ PC's features and provide examples of how neural time series data is often represented and saved. We address characteristics of the recorded signals and discuss Percept™ PC hardware and software capabilities in data pre-processing, signal filtering, and DBS lead performance. We explain the power spectrum of the data and how it is shaped by the filter response of Percept™ PC as well as the aliasing of the stimulation due to digitally sampling the data. We present Percept™ PC's ability to extract biomarkers that may be used to optimize stimulation therapy. We show how differences in lead type affects noise characteristics of the implanted leads from seven epilepsy patients enrolled in our clinical trial. Percept™ PC has sufficient signal-to-noise ratio, sampling capabilities, and stimulus artifact rejection for neural activity recording. Limitations in sampling rate, potential artifacts during stimulation, and shortening of battery life when monitoring neural activity at home were observed. Despite these limitations, Percept™ PC demonstrates potential as a useful tool for recording neural activity in order to optimize stimulation therapies to personalize treatment.


Asunto(s)
Estimulación Encefálica Profunda , Epilepsia , Temblor Esencial , Enfermedad de Parkinson , Humanos , Tálamo , Epilepsia/diagnóstico , Epilepsia/terapia , Enfermedad de Parkinson/terapia , Temblor Esencial/diagnóstico , Temblor Esencial/terapia
2.
Sci Rep ; 11(1): 10803, 2021 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-34031502

RESUMEN

Plant-associated bacteria can establish mutualistic relationships with plants to support plant health. Plant tissues represent heterogeneous niches with distinct characteristics and may thus host distinct microbial populations. The objectives of this study are to investigate the bacterial communities associated with two medicinally and commercially important plant species; Ginkgo biloba and Panax quinquefolius using high Throughput Sequencing (HTS) of 16S rRNA gene, and to evaluate the extent of heterogeneity in bacterial communities associated with different plant niches. Alpha diversity showed that number of operational taxonomic units (OTUs) varied significantly by tissue type. Beta diversity revealed that the composition of bacterial communities varied between tissue types. In Ginkgo biloba and Panax quinquefolius, 13% and 49% of OTUs, respectively, were ubiquitous in leaf, stem and root. Proteobacteria, Bacteroidetes, Actinobacteria and Acidobacteria were the most abundant phyla in Ginkgo biloba while Proteobacteria, Bacteroidetes, Actinobacteria, Plantomycetes and Acidobacteria were the most abundant phyla in Panax quinquefolius. Functional prediction of these bacterial communities using MicrobiomeAnalyst revealed 5843 and 6251 KEGG orthologs in Ginkgo biloba and Panax quinquefolius, respectively. A number of these KEGG pathways were predicted at significantly different levels between tissues. These findings demonstrate the heterogeneity, niche specificity and functional diversity of plant-associated bacteria.


Asunto(s)
Bacterias/clasificación , Ginkgo biloba/microbiología , Panax/microbiología , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN/métodos , Bacterias/genética , Bacterias/aislamiento & purificación , ADN Bacteriano/genética , ADN Ribosómico/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Filogenia , Hojas de la Planta/microbiología , Raíces de Plantas/microbiología , Tallos de la Planta/microbiología
3.
Sci Rep ; 11(1): 4331, 2021 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-33619286

RESUMEN

The demand for popular natural health products (NHPs) such as Black Cohosh is increasing considerably, which in turn challenges quality assurance (QA) throughout the supply chain. To detect and quantify the target species present in a given NHP, DNA-based molecular techniques such as Real-time quantitative PCR (qPCR) and digital PCR (dPCR) are standard tools in the food and pathogen testing industries. There is a gap in the literature concerning validated quantitative PCR methods for botanicals that can be utilized for QA and good manufacturing practices. The objective of this study is to develop an efficient quantification method using qPCR and dPCR techniques for the detection and quantification of Actaea racemosa (Black cohosh) NHPs from its potential adulterants. These developed methods are validated for applicability on commercial NHPs. Species-specific hydrolysis probe assays were designed to analyze the black cohosh NHPs using qPCR and dPCR techniques. The results confirmed that the developed qPCR and dPCR methods are highly precise for identifying and quantifying black cohosh NHPs, indicating their potential applicability in future routine industrial and laboratory testing. This enables a single qPCR test to determine not only the presence of a specific botanical, but also the amount when mixed with an adulterant.


Asunto(s)
Cimicifuga/clasificación , Cimicifuga/genética , Plantas Medicinales/clasificación , Plantas Medicinales/genética , Contaminación de ADN , ADN de Plantas , Etnobotánica/métodos , Etnobotánica/normas , Reacción en Cadena de la Polimerasa/métodos
4.
J AOAC Int ; 104(3): 836-846, 2021 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-33346838

RESUMEN

BACKGROUND: Actaea racemosa (black cohosh) herbal dietary supplements are commonly used to treat menopausal symptoms in women. However, there is a considerable risk of contamination of A. racemosa herbal products in the natural health product (NHP) industry, impacting potential efficacy. Authentication of A. racemosa products is challenging because of the standard, multi-part analytical chemistry methods that may be too costly and not appropriate for both raw and finished products. OBJECTIVE: In this paper, we discuss developing and validating quick alternative biotechnology methods to authenticate A. racemosa herbal dietary supplements, based on the use of a species-specific hydrolysis PCR probe assay. METHODS: A qPCR-based species-specific hydrolysis probe assay was designed, validated, and optimized for precisely identifying the species of interest using the following analytical validation criteria: (1) specificity (accuracy) in determining the target species ingredient, while not identifying other non-target species; (2) sensitivity in detecting the smallest amount of the target material; and (3) reliability (repeatability and reproducibility) in detecting the target species in raw materials on a real-time PCR platform. RESULTS: The results show that the species-specific hydrolysis probe assay was successfully developed for the raw materials and powders of A. racemosa. The specificity of the test was 100% to the target species. The efficiency of the assay was observed to be 99%, and the reliability of the assay was 100% for the raw/starting and powder materials. CONCLUSION: The method developed in this study can be used to authenticate and perform qualitative analysis of A. racemosa supplements.


Asunto(s)
Cimicifuga , Contaminación de Medicamentos , Femenino , Humanos , Extractos Vegetales , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados , Especificidad de la Especie
5.
Ann Clin Transl Neurol ; 7(12): 2356-2369, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33128504

RESUMEN

OBJECTIVE: Neuromodulatory anterior thalamic deep brain stimulation (DBS) is an effective therapy for intractable epilepsy, but few patients achieve complete seizure control with thalamic DBS. Other stimulation sites may be considered for anti-seizure DBS. We investigated bilateral low-frequency stimulation of the endopiriform nuclei (LFS-EPN) to control seizures induced by intracortically implanted cobalt wire in rats. METHODS: Chronic epilepsy was induced by cobalt wire implantation in the motor cortex unilaterally. Bipolar-stimulating electrodes were implanted into the EPN bilaterally. Continuous electroencephalography (EEG) was recorded using electrodes placed into bilateral motor cortex and hippocampus CA1 areas. Spontaneous seizures were monitored by long-term video-EEG, and behavioral seizures were classified based on the Racine scale. Continuous 1-Hz LFS-EPN began on the third day after electrode implantation and was controlled by a multi-channel stimulator. Stimulation continued until the rats had no seizures for three consecutive days. RESULTS: Compared with the control and sham stimulation groups, the LFS-EPN group experienced significantly fewer seizures per day and the mean Racine score of seizures was lower due to fewer generalized seizures. Ictal discharges at the epileptogenic site had significantly reduced theta band power in the LFS-EPN group compared to the other groups. INTERPRETATION: Bilateral LFS-EPN attenuates cobalt wire-induced seizures in rats by modulating epileptic networks. Reduced ictal theta power of the EEG broadband spectrum at the lesion site may be associated with the anti-epileptogenic mechanism of LFS-EPN. Bilateral EPN DBS may have therapeutic applications in human partial epilepsies.


Asunto(s)
Terapia por Estimulación Eléctrica , Epilepsia/terapia , Corteza Motora/fisiopatología , Corteza Piriforme , Ritmo Teta/fisiología , Animales , Región CA1 Hipocampal/fisiopatología , Estimulación Encefálica Profunda , Modelos Animales de Enfermedad , Electrocorticografía , Neuroestimuladores Implantables , Masculino , Ratas , Ratas Sprague-Dawley , Convulsiones
6.
BMJ Open ; 9(1): e023961, 2019 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-30782719

RESUMEN

INTRODUCTION: Delirium is a common complication of critical illness, associated with negative patient outcomes. Preventive or therapeutic interventions are mostly ineffective. Although relaxation-inducing approaches may benefit critically ill patients, no well-designed studies target delirium prevention as a primary outcome. The objective of this study is to assess feasibility and treatment effect estimates of a multimodal integrative intervention incorporating relaxation, guided imagery and moderate pressure touch massage for prevention of critical illness delirium and for related outcomes. METHODS AND ANALYSIS: Randomised, controlled, single-blinded trial with two parallel groups (1:1 allocation: intervention and standard care) and stratified randomisation (age (18-64 years and ≥65 years) and presence of trauma) with blocking, involving 104 patients with Intensive Care Delirium Screening Checklist (ICDSC): 0-3 recruited from two academic intensive care units (ICUs). Intervention group participants receive the intervention in addition to standard care for up to five consecutive days (or until transfer/discharge); control group participants receive standard care and a sham intervention. We will assess predefined feasibility outcomes, that is, recruitment rates and protocol adherence. The primary clinical outcome is incidence of delirium (ICDSC ≥4). Secondary outcomes include pain scores, inflammatory biomarkers, heart rate variability, stress and quality of life (6 weeks and 4 months) post-ICU discharge. Feasibility measures will be analysed descriptively, and outcomes will be analysed longitudinally. Estimates of effects will be calculated. ETHICS AND DISSEMINATION: The study has received approval from the Human Research Ethics Board, University of Alberta. Results will inform the design of a future multicentre trial. TRIAL REGISTRATION NUMBER: NCT02905812; Pre-results.


Asunto(s)
Delirio/terapia , Terapia por Relajación/métodos , Adolescente , Adulto , Enfermedad Crítica/psicología , Enfermedad Crítica/terapia , Delirio/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Proyectos Piloto , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Método Simple Ciego , Resultado del Tratamiento , Adulto Joven
7.
Epilepsia ; 59(6): 1198-1207, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29600809

RESUMEN

OBJECTIVE: To compare stereotactic radiosurgery (SRS) versus anterior temporal lobectomy (ATL) for patients with pharmacoresistant unilateral mesial temporal lobe epilepsy (MTLE). METHODS: This randomized, single-blinded, controlled trial recruited adults eligible for open surgery among 14 centers in the USA, UK, and India. Treatment was either SRS at 24 Gy to the 50% isodose targeting mesial structures, or standardized ATL. Outcomes were seizure remission (absence of disabling seizures between 25 and 36 months), verbal memory (VM), and quality of life (QOL) at 36-month follow-up. RESULTS: A total of 58 patients (31 in SRS, 27 in ATL) were treated. Sixteen (52%) SRS and 21 (78%) ATL patients achieved seizure remission (difference between ATL and SRS = 26%, upper 1-sided 95% confidence interval = 46%, P value at the 15% noninferiority margin = .82). Mean VM changes from baseline for 21 English-speaking, dominant-hemisphere patients did not differ between groups; consistent worsening occurred in 36% of SRS and 57% of ATL patients. QOL improved with seizure remission. Adverse events were anticipated cerebral edema and related symptoms for some SRS patients, and cerebritis, subdural hematoma, and others for ATL patients. SIGNIFICANCE: These data suggest that ATL has an advantage over SRS in terms of proportion of seizure remission, and both SRS and ATL appear to have effectiveness and reasonable safety as treatments for MTLE. SRS is an alternative to ATL for patients with contraindications for or with reluctance to undergo open surgery.


Asunto(s)
Lobectomía Temporal Anterior/métodos , Epilepsia del Lóbulo Temporal/radioterapia , Epilepsia del Lóbulo Temporal/cirugía , Radiocirugia/métodos , Adulto , Relación Dosis-Respuesta en la Radiación , Epilepsia Refractaria/radioterapia , Epilepsia Refractaria/cirugía , Epilepsia del Lóbulo Temporal/complicaciones , Epilepsia del Lóbulo Temporal/psicología , Femenino , Lateralidad Funcional , Humanos , Estudios Longitudinales , Masculino , Trastornos de la Memoria/diagnóstico , Trastornos de la Memoria/etiología , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico , Calidad de Vida , Método Simple Ciego , Resultado del Tratamiento , Trastornos de la Visión/diagnóstico , Trastornos de la Visión/etiología
8.
Mol Cell Proteomics ; 14(4): 870-81, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25616868

RESUMEN

Upon entry into mammalian host cells, the pathogenic bacterium Francisella must import host cell arginine to multiply actively in the host cytoplasm. We identified and functionally characterized an arginine transporter (hereafter designated ArgP) whose inactivation considerably delayed bacterial phagosomal escape and intracellular multiplication. Intramacrophagic growth of the ΔargP mutant was fully restored upon supplementation of the growth medium with excess arginine, in both F. tularensis subsp. novicida and F. tularensis subsp. holarctica LVS, demonstrating the importance of arginine acquisition in these two subspecies. High-resolution mass spectrometry revealed that arginine limitation reduced the amount of most of the ribosomal proteins in the ΔargP mutant. In response to stresses such as nutritional limitation, repression of ribosomal protein synthesis has been observed in all kingdoms of life. Arginine availability may thus contribute to the sensing of the intracellular stage of the pathogen and to trigger phagosomal egress. All MS data have been deposited in the ProteomeXchange database with identifier PXD001584 (http://proteomecentral.proteomexchange.org/dataset/PXD001584).


Asunto(s)
Arginina/metabolismo , Francisella/metabolismo , Interacciones Huésped-Patógeno , Fagosomas/microbiología , Proteínas Ribosómicas/metabolismo , Animales , Autofagia , Proteínas Bacterianas/metabolismo , Vacunas Bacterianas/inmunología , Análisis por Conglomerados , Citosol/metabolismo , Femenino , Francisella/patogenicidad , Macrófagos/metabolismo , Macrófagos/microbiología , Macrófagos/ultraestructura , Proteínas de Transporte de Membrana/metabolismo , Ratones Endogámicos BALB C , Viabilidad Microbiana , Modelos Biológicos , Mutación/genética , Fagosomas/metabolismo , Fagosomas/ultraestructura , Transporte de Proteínas , Proteoma/metabolismo , Estrés Fisiológico , Fracciones Subcelulares/metabolismo , Virulencia
9.
J Hepatol ; 62(1): 190-7, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25195547

RESUMEN

BACKGROUND & AIMS: This study's aim was to assess the histological and metabolic effects of n-3 polyunsaturated fatty acids (PUFAs) vs. placebo while adjusting for the impact of age and weight change in NASH patients. (ClinicalTrials.gov: NCT00681408). METHODS: Forty-one subjects with non-cirrhotic NASH were enrolled, and 34 completed the study. 17 received n-3 fish oil 3000 mg/day and 17 received placebo daily for 1 year with typical counselling on caloric intake and physical activity for all subjects. RESULTS: N-3- and placebo-treated groups showed no significant difference for the primary end point of NASH activity score (NAS) reduction ⩾ 2 points without fibrosis progression after adjustment for known covariates (n-3, 4/17 (23.5%); placebo, 3/17, (17.6%), p = 0.99). Among subjects with increased or stable weight, n-3 subjects showed a larger decrease in liver fat content by MRI than placebo-treated subjects (p = 0.014 for 2nd quartile, p = 0.003 for 3rd quartile of weight change). N-3 treatment showed significant fat reduction on the paired analysis of image-assisted fat morphometry regardless of weight loss or gain. Exercise capacity remained markedly reduced in all subjects. No independent effects on markers of hepatocyte injury or insulin sensitivity indices were observed. CONCLUSION: N-3 PUFAs at 3000 mg/day for one year did not lead to an improvement in the primary outcome of histological activity in NASH patients (⩾ 2 point NAS reduction). N-3 led to reduced liver fat by multiple measures. Other metabolic effects were not seen, although no detrimental effects were apparent. Whether longer duration, higher dose, or different composition of n-3 therapy would lead to additional benefits is uncertain.


Asunto(s)
Metabolismo Energético/efectos de los fármacos , Ácidos Grasos Omega-3/uso terapéutico , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Adulto , Anciano , Biopsia , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Estudios Retrospectivos
10.
J Trauma Acute Care Surg ; 77(5): 749-756, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25494428

RESUMEN

BACKGROUND: Each year, injuries affect 700 million people worldwide, more than 5 million people die of injuries, and 68,000 survivors remain permanently impaired. Half of all critically injured patients do not receive recommended care, and medical errors are common. Little is known about the aspects of injury care that are important to patients and their families. The purpose of this study was to explore the views of patients and families affected by injury on desired components of injury care in the hospital setting. METHODS: With the use of a grounded theory approach, this qualitative study involved focus groups with injured patients, family members of survivors, and bereaved family members from four Canadian trauma (injury care) centers. RESULTS: Thirty-eight participants included injured patients (n = 16), family members of survivors (n = 13), and bereaved family members (n = 9) across four trauma (injury care) centers in different jurisdictions. Participants articulated numerous themes reflecting important components of injury care organized across three domains as follows: clinical care (staff availability, professionalism, physical comfort, adverse events), holistic care (patient wellness, respect for patient and family, family access to patient, family wellness, hospital facilities, supportive care), and communication and information (among staff, with or from staff, content, delivery, and timing). Bereaved family members commented on decision making and end-of-life processes. Subthemes were revealed in most of these themes. Trends by site or type of participant were not identified. CONCLUSION: The framework of patient- and family-derived components of quality injury care could be used by health care managers and policy makers to guide quality improvement efforts. Further research is needed to extend and validate these components among injured patients and families elsewhere. Translating these components into quality indicators and blending those with measures that reflect a provider perspective may offer a comprehensive means of assessing injury care.

11.
Cell Microbiol ; 16(3): 434-49, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24134488

RESUMEN

In order to develop a successful infectious cycle, intracellular bacterial pathogens must be able to adapt their metabolism to optimally utilize the nutrients available in the cellular compartments and tissues where they reside. Francisella tularensis, the agent of the zoonotic disease tularaemia, is a highly infectious bacterium for a large number of animal species. This bacterium replicates in its mammalian hosts mainly in the cytosol of infected macrophages. We report here the identification of a novel amino acid transporter of the major facilitator superfamily of secondary transporters that is required for bacterial intracellular multiplication and systemic dissemination. We show that inactivation of this transporter does not affect phagosomal escape but prevents multiplication in the cytosol of all cell types tested. Remarkably, the intracellular growth defect of the mutant was fully and specifically reversed by addition of asparagine or asparagine-containing dipeptides as well as by simultaneous addition of aspartic acid and ammonium. Importantly, bacterial virulence was also restored in vivo, in the mouse model, by asparagine supplementation. This work unravels thus, for the first time, the importance of asparagine for cytosolicmultiplication of Francisella. Amino acid transporters are likely to constitute underappreciated players in bacterial intracellular parasitism.


Asunto(s)
Sistemas de Transporte de Aminoácidos/genética , Asparagina/metabolismo , Proteínas Bacterianas/genética , Francisella tularensis/crecimiento & desarrollo , Compuestos de Amonio/farmacología , Animales , Asparagina/farmacología , Ácido Aspártico/metabolismo , Ácido Aspártico/farmacología , Proteínas Bacterianas/farmacocinética , Línea Celular Tumoral , Francisella tularensis/metabolismo , Francisella tularensis/patogenicidad , Células Hep G2 , Humanos , Macrófagos/microbiología , Ratones , Ratones Endogámicos BALB C , Fagosomas/microbiología , Tularemia/microbiología
12.
New Phytol ; 196(4): 1240-1250, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23078229

RESUMEN

Genome size (C-value) and endopolyploidy (endoreduplication index, EI) are known to correlate with various morphological and ecological traits, in addition to phylogenetic placement. A phylogenetically controlled multivariate analysis was used to explore the relationships between DNA content and phenotype in angiosperms. Seeds from 41 angiosperm species (17 families) were grown in a common glasshouse experiment. Genome size (2C-value and 1Cx-value) and EI (in four tissues: leaf, stem, root, petal) were determined using flow cytometry. The phylogenetic signal was calculated for each measure of DNA content, and phylogenetic canonical correlation analysis (PCCA) explored how the variation in genome size and EI was correlated with 18 morphological and ecological traits. Phylogenetic signal (λ) was strongest for EI in all tissues, and λ was stronger for the 2C-value than the 1Cx-value. PCCA revealed that EI was correlated with pollen length, stem height, seed mass, dispersal mechanism, arbuscular mycorrhizal association, life history and flowering time, and EI and genome size were both correlated with stem height and life history. PCCA provided an effective way to explore multiple factors of DNA content variation and phenotypic traits in a phylogenetic context. Traits that were correlated significantly with DNA content were linked to plant competitive ability.


Asunto(s)
Tamaño del Genoma , Genoma de Planta , Magnoliopsida/anatomía & histología , Magnoliopsida/genética , Filogenia , Flores/genética , Magnoliopsida/microbiología , Magnoliopsida/fisiología , Análisis Multivariante , Micorrizas , Fenotipo , Hojas de la Planta/genética , Raíces de Plantas/genética , Tallos de la Planta/anatomía & histología , Tallos de la Planta/genética , Polen/anatomía & histología , Polen/genética , Poliploidía , Semillas/anatomía & histología , Semillas/genética
13.
Epilepsia ; 51(5): 899-908, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20331461

RESUMEN

PURPOSE: We report a multicenter, double-blind, randomized trial of bilateral stimulation of the anterior nuclei of the thalamus for localization-related epilepsy. METHODS: Participants were adults with medically refractory partial seizures, including secondarily generalized seizures. Half received stimulation and half no stimulation during a 3-month blinded phase; then all received unblinded stimulation. RESULTS: One hundred ten participants were randomized. Baseline monthly median seizure frequency was 19.5. In the last month of the blinded phase the stimulated group had a 29% greater reduction in seizures compared with the control group, as estimated by a generalized estimating equations (GEE) model (p = 0.002). Unadjusted median declines at the end of the blinded phase were 14.5% in the control group and 40.4% in the stimulated group. Complex partial and "most severe" seizures were significantly reduced by stimulation. By 2 years, there was a 56% median percent reduction in seizure frequency; 54% of patients had a seizure reduction of at least 50%, and 14 patients were seizure-free for at least 6 months. Five deaths occurred and none were from implantation or stimulation. No participant had symptomatic hemorrhage or brain infection. Two participants had acute, transient stimulation-associated seizures. Cognition and mood showed no group differences, but participants in the stimulated group were more likely to report depression or memory problems as adverse events. DISCUSSION: Bilateral stimulation of the anterior nuclei of the thalamus reduces seizures. Benefit persisted for 2 years of study. Complication rates were modest. Deep brain stimulation of the anterior thalamus is useful for some people with medically refractory partial and secondarily generalized seizures.


Asunto(s)
Núcleos Talámicos Anteriores/fisiología , Terapia por Estimulación Eléctrica/métodos , Epilepsia/terapia , Adulto , Estimulación Encefálica Profunda/efectos adversos , Estimulación Encefálica Profunda/métodos , Depresión/etiología , Método Doble Ciego , Terapia por Estimulación Eléctrica/efectos adversos , Epilepsias Parciales/epidemiología , Epilepsias Parciales/prevención & control , Epilepsias Parciales/terapia , Epilepsia/epidemiología , Epilepsia/prevención & control , Femenino , Estudios de Seguimiento , Lateralidad Funcional/fisiología , Humanos , Estudios Longitudinales , Masculino , Trastornos de la Memoria/epidemiología , Trastornos de la Memoria/etiología , Resultado del Tratamiento
14.
Neuropsychopharmacology ; 31(7): 1345-55, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16641939

RESUMEN

Currently available therapeutic interventions for treatment-resistant depression, including switch, combination, and augmentation strategies, are less than ideal. Observations of mood elevation during vagus nerve stimulation (VNS) therapy for pharmacoresistant epilepsy suggested a role for VNS therapy in refractory major depression and prompted clinical investigation of this neurostimulation modality. The VNS Therapy System has been available for treatment of pharmacoresistant epilepsy since 1997 and was approved by the US Food and Drug Administration for treatment-resistant depression in July, 2005. The physiology of the vagus nerve, mechanics of the VNS Therapy System, and efficacy and safety in pharmacoresistant epilepsy are reviewed. Promising results of VNS therapy for treatment-resistant depression have been forthcoming from both acute and long-term studies, evidenced in part by progressive improvements in depression rating scale scores during the 1st year of treatment with maintenance of response thereafter. VNS therapy is well tolerated in patients with either pharmacoresistant epilepsy or treatment-resistant depression. As in epilepsy, the mechanisms of VNS therapy of treatment-resistant depression are incompletely understood. However, evidence from neuroimaging and other studies suggests that VNS therapy acts via innervation of the nucleus tractus solitarius, with secondary projections to limbic and cortical structures that are involved in mood regulation, including brainstem regions that contain serotonergic (raphe nucleus) and noradrenergic (locus ceruleus) perikarya that project to the forebrain. Mechanisms that mediate the beneficial effects of VNS therapy for treatment-resistant depression remain obscure. Suggestions for future research directions are described.


Asunto(s)
Trastorno Depresivo Mayor/terapia , Terapia por Estimulación Eléctrica , Neurobiología , Nervio Vago , Animales , Resistencia a Medicamentos , Estudios de Evaluación como Asunto , Humanos , Factores de Tiempo , Nervio Vago/anatomía & histología
15.
Epilepsia ; 45(9): 1064-70, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15329071

RESUMEN

PURPOSE: To measure vagus nerve stimulation (VNS)-induced cerebral blood flow (CBF) effects after prolonged VNS and to compare these effects with immediate VNS effects on CBF. METHODS: Ten consenting partial epilepsy patients had positron emission tomography (PET) with intravenous [15O]H2O. Each had three control scans without VNS and three scans during 30 s of VNS, within 20 h after VNS began (immediate-effect study), and repeated after 3 months of VNS (prolonged study). After intrasubject subtraction of control from stimulation scans, images were anatomically transformed for intersubject averaging and superimposed on magnetic resonance imaging (MRI) for anatomic localization. Changes on t-statistical maps were considered significant at p < 0.05 (corrected for multiple comparisons). RESULTS: During prolonged studies, CBF changes were not observed in any regions that did not have CBF changes during immediate-effect studies. During both types of studies, VNS-induced CBF increases were similarly located in the bilateral thalami, hypothalami, inferior cerebellar hemispheres, and right postcentral gyrus. During immediate-effect studies, VNS decreased bilateral hippocampal, amygdalar, and cingulate CBF and increased bilateral insular CBF; no significant CBF changes were observed in these regions during prolonged studies. Mean seizure frequency decreased by 25% over a 3-month period between immediate and prolonged PET studies, compared with 3 months before VNS began. CONCLUSIONS: Seizure control improved during a period over which some immediate VNS-induced CBF changes declined (mainly over cortical regions), whereas other VNS-induced CBF changes persisted (mainly over subcortical regions). Altered synaptic activities at sites of persisting VNS-induced CBF changes may reflect antiseizure actions.


Asunto(s)
Encéfalo/irrigación sanguínea , Terapia por Estimulación Eléctrica/métodos , Epilepsia Parcial Compleja/terapia , Nervio Vago/fisiología , Adulto , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Cerebelo/irrigación sanguínea , Cerebelo/diagnóstico por imagen , Circulación Cerebrovascular/fisiología , Epilepsia Parcial Compleja/diagnóstico por imagen , Epilepsia Parcial Compleja/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Hipotálamo/irrigación sanguínea , Hipotálamo/diagnóstico por imagen , Imagen por Resonancia Magnética/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Radioisótopos de Oxígeno , Flujo Sanguíneo Regional/fisiología , Transmisión Sináptica/fisiología , Tálamo/irrigación sanguínea , Tálamo/diagnóstico por imagen , Tomografía Computarizada de Emisión/estadística & datos numéricos , Resultado del Tratamiento , Agua
16.
Neurology ; 59(6 Suppl 4): S3-14, 2002 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-12270962

RESUMEN

Experiments in acute and chronic animal models of epilepsy provide mechanistic insight into the acute abortive, acute prophylactic, and chronic progressive prophylactic, anti-seizure effects of vagus nerve stimulation (VNS) observed in human epilepsies, and demonstrate antiepileptogenic effects of VNS in the kindling model. Anatomic-physiologic studies, experimental epilepsy studies, and human imaging, EEG, and CSF studies suggest that multiple mechanisms underlie the antiseizure effects of VNS and that alterations of vagal parasympathetic efferent activities do not underlie these antiseizure effects. Putative antiseizure mechanisms are mediated by altered vagal afferent activities, and probably include altered activities in the reticular activating system, the central autonomic network, the limbic system, and the diffuse noradrenergic projection system. Anatomic-physiologic studies fully account for the common and rare adverse effects of VNS. Current understandings of antiepileptic drug (AED) and VNS therapeutic mechanisms strongly support the "common sense" interpretation of the clinical studies: i.e., adjunctive VNS can add antiseizure effect to any AED regimen, with no interactive toxicity and no effect on drug distribution and elimination.


Asunto(s)
Terapia por Estimulación Eléctrica , Epilepsia/fisiopatología , Epilepsia/terapia , Nervio Vago/fisiología , Animales , Humanos
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