Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 48
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Small ; : e2401139, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39036823

RESUMEN

Core-shell gallium nitride (GaN)-based nanowires offer noteworthy opportunities for innovation in high-frequency opto- and microelectronics. This work delves deeply into the physical properties of crystalline GaN nanowires with aluminum and hafnium oxide shells. Particular attention is paid to partial coverage of nanowires, resulting with exceptional properties. First, the crystal lattice relaxation is observed by X-ray diffraction, photoluminescence, and Raman spectroscopy measurements. A high potential of partial coverage for optoelectronic applications is revealed with photo- and cathodoluminescence spectra along with an exploration of their temperature dependency. Next, the study focuses on understanding the mechanisms behind the observed enhancement of the luminescence efficiency. It is confirmed that nanowires are effectively protected against photoadsorption using partial coatings. This research advances the frontiers of nanotechnology, investigating the benefits of partial coverage, and shedding light on its complex interaction with cores.

2.
Neurol Neurochir Pol ; 58(3): 256-273, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38864766

RESUMEN

INTRODUCTION: Drug-resistant epilepsy (DRE) remains poorly-controlled in c.33% of patients, and up to 50% of patients suffering from DRE are deemed not to be suitable candidates for resective surgery. For these patients, deep brain stimulation (DBS) may constitute the last resort in the treatment of DRE. STATE OF THE ART: We undertook a systematic review of the current literature on DBS efficacy and the safety of two thalamic nuclei-anterior nucleus of the thalamus (ANT) and the centromedian nucleus of the thalamus in the management of patients with DRE. A search using two electronic databases, the Medical Literature, Analysis, and Retrieval System on-line (MEDLINE) and the Cochrane Central Register of Controlled Trials (CEN-TRAL) was conducted. CLINICAL IMPLICATIONS: We found 30 articles related to ANT DBS and 13 articles related to CMN DBS which were further analysed. Based on the clinical research articles, we found a mean seizure frequency reduction for both thalamic nuclei. For ANT DBS, the mean seizure frequency reduction ranged from 48% to 75%, and for CMN DBS from 46.7% to 91%. The responder rate (defined as at least 50% reduction in seizure frequency) was reported to be 53.2-75% for patients after ANT DBS and 50-90% for patients after CMN DBS. FUTURE DIRECTIONS: ANT and CMN DBS appear to be safe and efficacious treatments, particularly in patients with refractory partial seizures and primary generalised seizures. ANT DBS reduces most effectively seizures originating in the temporal and frontal lobes. CMN DBS reduces mostly primary generalised tonic-clonic and atypical absences and atonic seizures. Seizures related to Lennox-Gastaut syndrome respond very favourably to CMN DBS.


Asunto(s)
Núcleos Talámicos Anteriores , Estimulación Encefálica Profunda , Epilepsia Refractaria , Núcleos Talámicos Intralaminares , Humanos , Estimulación Encefálica Profunda/métodos , Epilepsia Refractaria/terapia , Resultado del Tratamiento
3.
Neurol Neurochir Pol ; 58(4): 393-404, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39093168

RESUMEN

INTRODUCTION: Temporal lobe epilepsy (TLE) is the most common cause of focal onset seizures, affecting 40% of adolescents and adults with epilepsy. TLE is also one of the most common drug resistant forms of epilepsy. Surgical resection remains the treatment of choice for TLE, but not all patients with TLE are suitable candidates for resective neurosurgery. For such patients, deep brain stimulation (DBS) of the hippocampus remains a reversible and efficient treatment alternative. STATE OF THE ART: We undertook a systematic review of the literature on hippocampal DBS efficacy and safety in the management of patients with TLE. A search using two electronic databases, the Medical Literature, Analysis, and Retrieval System on-line (MEDLINE) and the Cochrane Central Register of Controlled Trials (CEN-TRAL), was conducted. CLINICAL IMPLICATIONS: We found 14 articles related to hippocampal DBS for the treatment of TLE. The responder rate (defined as at least 50% reduction in seizure frequency) for all patients was 83.4%, Of 99 patients treated by hippocampal DBS, 82 were regarded as responders, and 17 as non-responders. FUTURE DIRECTIONS: Hippocampal DBS appears to be a safe and efficacious treatment alternative for patients who are not candidates for temporal lobectomy or selective amygdalohippocampectomy due to serious postoperative cognitive deficits. In selected patients with TLE, this neuromodulatory therapy may be very safe and efficacious.


Asunto(s)
Estimulación Encefálica Profunda , Epilepsia Refractaria , Epilepsia del Lóbulo Temporal , Hipocampo , Humanos , Estimulación Encefálica Profunda/efectos adversos , Estimulación Encefálica Profunda/métodos , Epilepsia Refractaria/fisiopatología , Epilepsia Refractaria/terapia , Epilepsia del Lóbulo Temporal/fisiopatología , Epilepsia del Lóbulo Temporal/terapia , Hipocampo/fisiopatología , Resultado del Tratamiento
4.
Int J Mol Sci ; 23(23)2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36499038

RESUMEN

As 30% of epileptic patients remain drug-resistant, seizure prediction is vital. Induction of epileptic seizure is a complex process that can depend on factors such as intrinsic neuronal excitability, changes in extracellular ion concentration, glial cell activity, presence of inflammation and activation of the blood−brain barrier (BBB). In this study, we aimed to assess if levels of serum proteins associated with BBB can predict seizures. Serum levels of MMP-9, MMP-2, TIMP-1, TIMP-2, S100B, CCL-2, ICAM-1, P-selectin, and TSP-2 were examined in a group of 49 patients with epilepsy who were seizure-free for a minimum of seven days and measured by ELISA. The examination was repeated after 12 months. An extensive medical history was taken, and patients were subjected to a follow-up, including a detailed history of seizures. Serum levels of MMP-2, MMP-9, TIMP-1, CCL-2, and P-selectin differed between the two time points (p < 0.0001, p < 0.0001, p < 0.0001, p < 0.0001, p = 0.0035, respectively). General linear model analyses determined the predictors of seizures. Levels of MMP-2, MMP-9, and CCL-2 were found to influence seizure count in 1, 3, 6, and 12 months of observation. Serum levels of MMP-2, MMP-9, and CCL-2 may be considered potential biomarkers for seizure prediction and may indicate BBB activation.


Asunto(s)
Barrera Hematoencefálica , Epilepsia , Humanos , Barrera Hematoencefálica/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Convulsiones/diagnóstico , Convulsiones/metabolismo , Epilepsia/diagnóstico , Epilepsia/metabolismo , Biomarcadores/metabolismo , Proteínas Sanguíneas/metabolismo
5.
J Sleep Res ; 30(1): e13031, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32243038

RESUMEN

Physicians belong to the risk group for sleep disorders as a result of work related stress, excessive working time, large amount of on-call duties and shift work. Poor sleep quality of healthcare providers threatens not only their safety, but also the safety of their patients. This study examines if there are any differences in how working either long hours or at night duties relates to self-reported sleep time, sleep quality and daytime sleepiness in primary care physicians. We analyzed data from a survey research of 807 participants. Respondents were divided into four groups based on their reported work hours per week and number of nights on duty per month. Overtime was associated with shorter sleep time and worse subjective sleep quality even when compared with that of participants who work on night duties. All investigated groups of participants reported short sleep latencies which suggests that sleep debt is a common problem in this population. Surprisingly in the case of poor sleep quality participants rarely used recommended methods like regular physical activity or specialist advice. The most frequently reported answer was that they do nothing to improve sleep and every third participants uses hypnotics to do that. These results suggest that primary care physicians despite being at high risk for sleep disorders due to working overtime and at night, pay less attention to their sleep quality and do not use recommended strategies to improve it.


Asunto(s)
Médicos de Atención Primaria/psicología , Trastornos del Sueño-Vigilia/psicología , Tolerancia al Trabajo Programado/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad
6.
J Sleep Res ; 28(2): e12679, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-29516562

RESUMEN

Quantitative electroencephalogram analysis (e.g. spectral analysis) has become an important tool in sleep research and sleep medicine. However, reliable results are only obtained if artefacts are removed or excluded. Artefact detection is often performed manually during sleep stage scoring, which is time consuming and prevents application to large datasets. We aimed to test the performance of mostly simple algorithms of artefact detection in polysomnographic recordings, derive optimal parameters and test their generalization capacity. We implemented 14 different artefact detection methods, optimized parameters for derivation C3A2 using receiver operator characteristic curves of 32 recordings, and validated them on 21 recordings of healthy participants and 10 recordings of patients (different laboratory) and considered the methods as generalizable. We also compared average power density spectra with artefacts excluded based on algorithms and expert scoring. Analyses were performed retrospectively. We could reliably identify artefact contaminated epochs in sleep electroencephalogram recordings of two laboratories (healthy participants and patients) reaching good sensitivity (specificity 0.9) with most algorithms. The best performance was obtained using fixed thresholds of the electroencephalogram slope, high-frequency power (25-90 Hz or 45-90 Hz) and residuals of adaptive autoregressive models. Artefacts in electroencephalogram data can be reliably excluded by simple algorithms with good performance, and average electroencephalogram power density spectra with artefact exclusion based on algorithms and manual scoring are very similar in the frequency range relevant for most applications in sleep research and sleep medicine, allowing application to large datasets as needed to address questions related to genetics, epidemiology or precision medicine.


Asunto(s)
Artefactos , Electroencefalografía/métodos , Sueño/fisiología , Adulto , Algoritmos , Humanos , Masculino , Estudios Retrospectivos , Adulto Joven
7.
Pharmacopsychiatry ; 51(4): 144-147, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29325180

RESUMEN

INTRODUCTION: One of the common side effects of antipsychotic drugs is excessive sedation. The treatment with antipsychotics often manifests as an increase in slow wave activity in electroencephalography (EEG). The aim of this study was to analyze EEG recordings of patients treated with a non-sedative antipsychotic drug sertindole with regard to its adverse effects and clinical efficacy. PATIENTS AND METHODS: EEG recordings of 45 patients (27 females, mean age 30.1±8.7 years) with schizophrenia were analyzed. EEG recordings were categorized based on abnormalities severity. The clinical efficacy was rated on the Clinical Global Impression Scale. RESULTS: Abnormalities from mild to moderate were found in 29% of the group. Clinical improvement was observed in 80% of patients. Sedation/daytime sleepiness was present in 7% of patients. Other side effects were prolongation of QTc (11%, severe 4%), insomnia (9%), extrapyramidal symptoms (7%), and heart palpitations (2%). CONCLUSIONS: Patients treated with sertindole do not show side effects similar to those found during treatment with other antipsychotic drugs. Increased slow wave activity in EEG and sedation were absent in the majority of the investigated patients.


Asunto(s)
Antipsicóticos/uso terapéutico , Ondas Encefálicas/efectos de los fármacos , Imidazoles/uso terapéutico , Indoles/uso terapéutico , Esquizofrenia Paranoide/tratamiento farmacológico , Esquizofrenia Paranoide/fisiopatología , Adulto , Electroencefalografía , Femenino , Humanos , Masculino , Resultado del Tratamiento , Adulto Joven
8.
Curr Psychiatry Rep ; 19(9): 63, 2017 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-28791566

RESUMEN

PURPOSE OF REVIEW: The aim of this review article was to summarize recent publications on effects of antidepressants on sleep and to show that these effects not only depend on the kind of antidepressant drugs but are also related to the dose, the time of drug administration, and the duration of the treatment. RECENT FINDINGS: Complaints of disrupted sleep are very common in patients suffering from depression, and they are listed among diagnostic criteria for this disorder. Moreover, midnocturnal insomnia is the most frequent residual symptom of depression. Thus, all antidepressants should normalize sleep. However, at least in short-term treatment, many antidepressants with so-called activating effects (e.g. fluoxetine, venlafaxine) may disrupt sleep, while others with sedative properties (e.g., doxepin, mirtazapine, trazodone) rapidly improve sleep, but may cause problems in long-term treatment due to oversedation.For sleep-promoting action, the best effects can frequently be achieved with a very low dose, administered early enough before bedtime and importantly, always as a part of more complex interventions based on the cognitive-behavioral protocol to treat insomnia (CBT-I). For successful treatment of depression, it is necessary to understand the effects of antidepressants on sleep. Each physician should also be aware that some antidepressants may worsen or induce primary sleep disorders like restless legs syndrome, sleep bruxism, REM sleep behavior disorder, nightmares, and sleep apnea, which may result from an antidepressant-induced weight gain.


Asunto(s)
Antidepresivos/efectos adversos , Trastorno Depresivo/tratamiento farmacológico , Trastornos del Sueño-Vigilia/inducido químicamente , Sueño/efectos de los fármacos , Antidepresivos/administración & dosificación , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Humanos , Factores de Tiempo
9.
J Sleep Res ; 25(3): 356-64, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26809504

RESUMEN

Narcolepsy with cataplexy is a rare disease with an estimated prevalence of 0.02% in European populations. Narcolepsy shares many features of rare disorders, in particular the lack of awareness of the disease with serious consequences for healthcare supply. Similar to other rare diseases, only a few European countries have registered narcolepsy cases in databases of the International Classification of Diseases or in registries of the European health authorities. A promising approach to identify disease-specific adverse health effects and needs in healthcare delivery in the field of rare diseases is to establish a distributed expert network. A first and important step is to create a database that allows collection, storage and dissemination of data on narcolepsy in a comprehensive and systematic way. Here, the first prospective web-based European narcolepsy database hosted by the European Narcolepsy Network is introduced. The database structure, standardization of data acquisition and quality control procedures are described, and an overview provided of the first 1079 patients from 18 European specialized centres. Due to its standardization this continuously increasing data pool is most promising to provide a better insight into many unsolved aspects of narcolepsy and related disorders, including clear phenotype characterization of subtypes of narcolepsy, more precise epidemiological data and knowledge on the natural history of narcolepsy, expectations about treatment effects, identification of post-marketing medication side-effects, and will contribute to improve clinical trial designs and provide facilities to further develop phase III trials.


Asunto(s)
Bases de Datos Factuales , Narcolepsia , Sistema de Registros , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Cataplejía/tratamiento farmacológico , Cataplejía/epidemiología , Bases de Datos Factuales/normas , Europa (Continente)/epidemiología , Femenino , Humanos , Difusión de la Información , Internet , Masculino , Persona de Mediana Edad , Narcolepsia/tratamiento farmacológico , Narcolepsia/epidemiología , Fenotipo , Vigilancia de Productos Comercializados , Estudios Prospectivos , Control de Calidad , Enfermedades Raras/tratamiento farmacológico , Enfermedades Raras/epidemiología , Sistema de Registros/normas , Adulto Joven
10.
Epilepsy Behav Rep ; 27: 100677, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38845792

RESUMEN

Temporal lobe epilepsy (TLE) is the most common form of drug-resistant epilepsy. The main pathological changes primarily involve hippocampal sclerosis (HS). Early resective surgery of the sclerotic hippocampus is typically associated with favorable clinical outcomes. However, not all patients are suitable candidates for resective surgery of mesial temporal lobe structures. Therefore, alternative treatment modalities should be considered. We present the case of a 50-year-old right-handed woman with left HS who underwent unilateral subiculum stimulation for drug-resistant epilepsy (DRE). Since the age of 10, the patient had been experiencing focal to bilateral tonic-clonic seizures (FBTCS). Despite multiple antiseizure medications, she experienced 12 to 17 FBTCS per month in the last two years. Due to concerns about potential memory decline and personal preferences, she refused resective surgery. As an alternative, the patient underwent left unilateral subiculum stimulation. The stimulation resulted in a nearly 67 % reduction in seizure frequency at the last follow-up (20 months after surgery). This case highlights that drug-resistant epilepsy may be effectively treated with subicular stimulation in patients with HS.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA