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1.
Appl Psychophysiol Biofeedback ; 43(1): 1-11, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28871504

RESUMEN

Information systems (IS) community is increasingly interested in employing neuroscience tools and methods in order to develop new theories concerning Human-computer interaction (HCI) and further understand IS acceptance models. The new field of NeuroIS has been introduced to address these issues. NeuroIS researchers have proposed encephalography (EEG), among other neuroscience instruments, as a valuable usability metric, when used effectively in appropriately designed experiments. Moreover, numerous researchers have suggested that EEG frontal asymmetry may serve as an important metric of user experience. Based on the aforementioned evidence, this study aims to integrate frontal asymmetry with Technology acceptance model (TAM). Particularly, we assumed that frontal asymmetry might predict users' perceptions regarding Usefulness and Ease of Use. Furthermore, we hypothesized that frontal asymmetry might also affect (influence) users' Perceived Playfulness. Specifically, 82 (43 females and 39 males) undergraduate students were chosen to use a Computer-Based Assessment (while being connected to the EEG) in the context of an introductory informatics course. Results confirmed our hypothesis as well as points of theory about Information technology (IT) acceptance variables. This is one of the first studies to suggest that frontal asymmetry could serve as a valuable tool for examining IT acceptance constructs and better understanding HCI.


Asunto(s)
Electroencefalografía/métodos , Tecnología de la Información , Interfaz Usuario-Computador , Adulto , Biorretroalimentación Psicológica , Femenino , Humanos , Masculino , Encuestas y Cuestionarios , Adulto Joven
2.
Neurotoxicology ; 52: 57-63, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26542247

RESUMEN

BACKGROUND: Antiepileptic drugs (AEDs) are mainly used to control cortical hyperexcitability. Some of them (e.g. phenytoin (PHT) and topiramate (TPM)) have also effects on the peripheral nervous system (PNS). Lacosamide (LCM) is a novel AED that stabilizes hyperexcitable neuronal membranes by selectively enhancing the slow inactivation of voltage-gated sodium channels (VGSCs). Although the mechanism of action of LCM is fairly well understood, there are no in vitro data available regarding any possible PNS effects of LCM. OBJECTIVE: To investigate, in vitro, the effects of LCM on peripheral nerve excitability in comparison with PHT and TPM, two AEDs that act, in part, by stabilizing the fast inactivation state of VGSCs. METHODS: Experiments were conducted on the isolated sciatic nerve of the adult rat using standard electrophysiological methods. The effects of LCM on the amplitude and latency of the evoked compound action potential (CAP) during a 48h period of drug exposure were recorded and compared with the effects of PHT and TPM. RESULTS: LCM produced inhibitory effects on CAP at concentrations significantly higher than the therapeutic levels (>25µg/ml). At these concentrations (62.57-125.15µg/ml), an acute and immediate increment of the latency and decrement of the amplitude of the CAP were observed. In contrast to LCM, PHT caused an acute decrement in the amplitude as well as an increment in the latency of the CAP even at subtherapeutic levels (5µg/ml). With regard to TPM, the amplitude of the CAP was not affected at the supratherapeutic concentrations but at the therapeutic concentration of 33.94µg/ml a reduced decrement of the CAP amplitude compared to the controls was observed. CONCLUSIONS: LCM, PHT and TPM exert differential effects on peripheral nerve excitability. PHT inhibited the sciatic nerve CAP even at subtherapeutic levels whereas LCM was safe within the therapeutic concentration range. TPM did not affect the CAP amplitude even at high supratherapeutic concentrations whereas in the therapeutic range a neuroprotective effect was observed. Possible underlying mechanisms and the clinical implications of these findings are discussed.


Asunto(s)
Acetamidas/efectos adversos , Potenciales de Acción/efectos de los fármacos , Fructosa/análogos & derivados , Fenitoína/efectos adversos , Nervio Ciático/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Estimulación Eléctrica , Femenino , Fructosa/efectos adversos , Técnicas In Vitro , Lacosamida , Masculino , Ratas , Nervio Ciático/fisiología , Topiramato
3.
Angiology ; 65(5): 372-8, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-23620311

RESUMEN

Novel anticoagulants (NOACs) are the recent therapeutic breakthrough in the prophylaxis of stroke in patients with nonvalvular atrial fibrillation (NVAF). Patients with NVAF seem to have a high atherosclerotic burden, but it has not yet been established whether these agents also protect against cardiovascular disease (CVD). Different NOACs could have cardioprotective properties of different importance, but data come only from indirect comparisons. Patients with NVAF are at risk of stroke when there is concomitant atherosclerosis that also necessitates optimal treatment to reduce CVD risk. Combining antiplatelets with anticoagulants is a common clinical scenario and not always justified by current data and guidelines, putting patients at unnecessary bleeding risk. This review provides current knowledge about the cardioprotective properties of NOACs, the clinical importance of the link between CVD and NVAF, and the pitfalls of combining antiplatelet therapy with warfarin or NOACs.


Asunto(s)
Anticoagulantes/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Fibrinolíticos/uso terapéutico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Accidente Cerebrovascular/prevención & control , Anticoagulantes/efectos adversos , Fibrilación Atrial/complicaciones , Quimioterapia Combinada , Fibrinolíticos/efectos adversos , Hemorragia/inducido químicamente , Humanos , Inhibidores de Agregación Plaquetaria/efectos adversos , Factores de Riesgo , Accidente Cerebrovascular/etiología , Resultado del Tratamiento
4.
Int J Neurosci ; 122(1): 26-34, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21883027

RESUMEN

The purpose of this study was the evaluation of pupil light reflex (PLR) in patients with Parkinson's disease (PD) by using a modern pupillometry system and the investigation of its potential relationship with dopamine transporter imaging (DaTSCAN), which is an objective method for the evaluation of presynaptic dopaminergic system. PLR was evaluated using pupillometry in 35 patients with PD without clinical evidence of autonomic dysfunction and 44 healthy matched controls. PLR was elicited using a fully automated pupillometry system and six parameters were measured. Dopamine transporter imaging was performed using radioactive ioflupane (123)I-FP-CIT [(123)I-N-ω-fluoropropyl-2ß-carbomethoxy-3ß-(4-iodophenyl)-nortropane]. A significant increase in latency and a significant decrease in amplitude, maximum constriction velocity, as well as maximum acceleration were observed in PD patients. There was no significant difference in initial radius and minimum radius values. Investigating the relationship between pupillometry parameters and (123)I-FP-CIT binding values, we correlated values from the semiquantitative analysis of radioligand uptake with pupillometry parameters, but we found no significant correlation. This study demonstrates PLR impairment in patients with PD without overt autonomic dysfunction. This impairment does not seem to correspond to the reduction of radioligand binding in the striatum as the result of presynaptic dopaminergic dysfunction, suggesting a different deterioration rate of these systems.


Asunto(s)
Técnicas de Diagnóstico Oftalmológico , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/fisiología , Enfermedad de Parkinson/diagnóstico por imagen , Trastornos de la Pupila/diagnóstico , Ensayo de Unión Radioligante/métodos , Tropanos , Anciano , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/fisiopatología , Trastornos de la Pupila/etiología , Trastornos de la Pupila/fisiopatología , Cintigrafía , Reflejo Anormal/fisiología , Tropanos/metabolismo
5.
Int J Neurosci ; 121(1): 37-43, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21034369

RESUMEN

We evaluated pupil light reflex (PLR) in patients with Parkinson's disease (PD) and normal controls by means of pupillometry and explored its possible relation to clinical characteristics in parkinsonian patients. PLR was evaluated using pupillometry in 66 patients with PD without clinical evidence of autonomic dysfunction and 44 healthy matched controls. PLR was elicited by single flash stimuli of 24.6 candelas/m(2) intensity and 20 ms duration, and six parameters were studied after full recording of pupil's movement. A significant increase in latency (T1) and significant decrease in amplitude (R1-R2), maximum constriction velocity (V(max)), as well as maximum acceleration (AC(max)) was found in parkinsonian patients. There was no significant difference in initial radius (R1) and minimum radius (R2) values. Of the parameters studied, AC(max) emerged as a significant predictor for discrimination between PD patients and controls. There was no significant correlation between pupillometry parameters and clinical characteristic of patients (disease duration, stage, and the Unified Parkinson's Disease Rating motor scale). The study demonstrates PLR disorder in PD patients even without overt clinical autonomic dysfunction. Pupillometry appears to be a useful and noninvasive method for exploration of PLR alterations in PD and may prove to be useful for the early detection of subclinical autonomic nervous system dysfunction.


Asunto(s)
Examen Neurológico/instrumentación , Enfermedad de Parkinson/fisiopatología , Reflejo Pupilar/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/diagnóstico , Estimulación Luminosa/métodos , Curva ROC
6.
Cardiol J ; 17(1): 65-72, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20104459

RESUMEN

BACKGROUND: Purpose of this study was to examine pupil size changes and mobility in normal subjects and in heart failure (HF) patients. METHODS: Sixteen stable patients with New York Heart Association (NYHA) class II or III heart failure and sixteen control subjects were studied. Pupillary reaction to light was recorded and nine parameters from this data were measured, reported and then compared in both groups of subjects. RESULTS: Patients with HF had abnormal pupillary function compared with normal subjects. Pupillary light reflex variables differed significantly between two groups (p < 0.05) except baseline radius (R1), minimum radius (R2) and time for maximum constriction (T3). A significant decrease in maximum constriction velocity (VCmax; p < 0.001) and maximum constriction acceleration (ACmax; p < 0.001) was observed in HF subjects. Furthermore, significantly higher values in percentage recovery-redilatation (%R; p < 0.001), percentage R2/R1 (%R2/R1; p < 0.05), latency (T1; p < 0.05) and time for maximum velocity (T2; p < 0.05) were found in the same group. CONCLUSIONS: Of the parameters studied, R1 and %R are governed mainly by the action of the sympathetic nervous system, through norepinephrine. The rest are governed mainly by parasympathetic nervous system, through acetylcholine. The results of our study demonstrate generalized adrenergic activation and parasympathetic withdrawal, which are present in HF.


Asunto(s)
Sistema Nervioso Autónomo/fisiopatología , Insuficiencia Cardíaca/fisiopatología , Reflejo Pupilar , Anciano , Humanos , Rayos Infrarrojos , Persona de Mediana Edad , Norepinefrina/sangre , Sistema Nervioso Parasimpático/fisiopatología , Sistema Nervioso Simpático/fisiopatología , Factores de Tiempo
7.
Int J Psychophysiol ; 72(2): 97-101, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19047001

RESUMEN

The aim of this study is to investigate the changes of the pupil's light reflex (PLR) and mobility in Parkinson's disease (PD) patients with and without cognitive disorder. Twenty two (22) patients (ten males, twelve females, mean age: 72.7+/-7.3 years) with identified PD entered the study. The patients were examined with the Mini Mental State Examination (MMSE), the Wechsler II Memory Scale (WMS II) and the Hamilton Depression Scale (HAM-D17). Eleven (11) patients (five males, six females, mean age: 72.09+/-7.06 years) were free of any cognitive deficits and eleven (11) patients (five males, six females, mean age: 73.36+/-7.55 years) had cognitive disorder according to the aforementioned scales. None of the patients satisfied the DSM-IV-TR criteria for depression or anxiety disorder. The patients underwent a pupillometric study in both eyes with single flash stimuli of 24.6 candelas/m(2) intensity and 20 ms duration. The pupillometric parameters that were studied were: Latency for the onset of Constriction (T1), Baseline Pupil Radius (R1), Minimum Pupil Radius after the pupil reaction to light (R2), Amplitude (AMP, R1-R2), Time for maximum Miosis (T2), Maximum Constriction Velocity (VCmax) and Maximum Constriction Acceleration (ACmax). The pupillometric findings of each group were compared to those of an age and sex matched group of eleven healthy subjects. Furthermore, a comparison between the findings of the two groups was conducted. ACmax and VCmax were significantly lower in patients without (PD) and with coexisting cognitive impairment (PDC) compared to normal subjects (NC) (p<0.001). Patients with cognitive impairment (PDC) had significantly lower levels of ACmax, VCmax and AMP than patients without cognitive deficits (PD). Cognitive impairment in PD, which mainly reflects a central cholinergic deficit, may be a crucial pathogenetic factor for the decrease in the aforementioned pupillometric parameters. VCmax and ACmax can be considered as the most sensitive indicators of this central cholinergic deficiency.


Asunto(s)
Trastornos del Conocimiento/patología , Enfermedad de Parkinson/patología , Pupila/fisiología , Reflejo Pupilar/fisiología , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Trastornos del Conocimiento/complicaciones , Humanos , Luz , Enfermedad de Parkinson/complicaciones , Tiempo de Reacción/fisiología
8.
Qual Life Res ; 17(7): 987-96, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18663600

RESUMEN

PURPOSE: The aim was to study the influence of patients' age, frequency and type of seizures, disease duration, number of AEDs and use of benzodiazepines on the quality of life of patients with epilepsy. PATIENTS AND METHODS: We consecutively identified 223 patients with epilepsy who attended the epilepsy outpatient clinics at three university hospitals in Greece. Quality of life was evaluated by QOLIE-31. One-way analysis was used to assess the association of the studied factors and QOLIE-31 subscales. After checking for co-linearity, we performed multivariate stepwise linear regression analysis with all the variables that on univariate analysis showed a statistically significant effect on each subscale of QOLIE-31 to explore which of the studied factors affect independently on QOLIE-31 scores. RESULTS: Of a total of 223 patients, 118 (52.95%) were men; mean age was 35.18 +/- 13.22; mean duration of the disease was 13 years; 58 (26%) patients had generalized seizures, 93 (41.7%) had PS, and 72 (32.3%) of the patients had PsG; 85 (38.1%) were on polytherapy and 38 (17%) were taking benzodiazepines. Independent factors affecting QoL were: seizure frequency (Overall QoL P = 0.0001, Seizure worry and Emotional well-being P < 0.0001, Energy/fatigue and Social functioning P = 0.01); duration of the disease (Overall QoL and Energy/fatigue P = 0.01, Seizure worry P = 0.008, Cognitive functioning P < 0.0001); polytherapy only for the Emotional well-being P < 0.0001; and use of benzodiazepines (Overall QoL, Energy/fatigue, Social functioning P = 0.002, Cognitive functioning P < 0.0001). CONCLUSION: Our findings suggest that QoL in epileptic patients might be affected, in addition to the other established factors (high frequency of seizures and polytherapy), by the daily use of benzodiazepines as adjunctive therapy. Change of medical strategy concerning this medication may lead to improving the QoL of these patients.


Asunto(s)
Epilepsia/psicología , Calidad de Vida , Convulsiones/clasificación , Perfil de Impacto de Enfermedad , Adolescente , Adulto , Anciano , Benzodiazepinas/efectos adversos , Benzodiazepinas/uso terapéutico , Emociones , Epilepsia/clasificación , Epilepsia/tratamiento farmacológico , Femenino , Grecia , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Convulsiones/prevención & control , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios
9.
Seizure ; 17(7): 588-94, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18396419

RESUMEN

The frequency of sleep disturbances in patients with epilepsy and their impact on quality of life (QoL) have been documented in a few reports, and the results are conflicting. We identified 124 consecutive epilepsy out-patients who visited the epilepsy out-patient clinics at the University Hospital of Alexandroupolis, the AHEPA Hospital in Thessaloniki and the Aeginitio Hospital in Athens. We measured excessive daytime sleepiness (EDS) with the Epworth Sleepiness Scale (ESS), obstructive sleep apnea (OSA) with the Sleep Apnea scale of the Sleep Disorders Questionnaire (SA-SDQ), and insomnia with the Athens Insomnia Scale (AIS). We evaluated quality of life by the Quality of Life in Epilepsy Inventory (QOLIE-31). EDS was found in 16.9% (21/124) of epileptic patients, OSA in 28.2% (35/124), and insomnia in 24.6% (30/122). In multivariate analysis, we found that insomnia was an independent negative factor for Total score (p<0.001), Overall QoL (p=0.002), Emotional well-being (p<0.001), Energy/fatigue (p<0.001), Cognitive functioning (p=0.04) and Social functioning (p=0.03), and OSA only for Cognitive functioning (p=0.01). According to our findings, EDS, OSA, and insomnia are frequent in epileptic patients. Epileptic patients with sleep disturbance, mainly insomnia, have significant QoL impairment.


Asunto(s)
Epilepsia/complicaciones , Epilepsia/psicología , Calidad de Vida , Trastornos del Sueño-Vigilia/etiología , Trastornos del Sueño-Vigilia/psicología , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Trastornos del Sueño-Vigilia/epidemiología , Encuestas y Cuestionarios
10.
Int J Neurosci ; 117(4): 443-51, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17365127

RESUMEN

This article attempts to describe a very unusual case of a boy aged 15, who has had intractable epileptic phenomena, mental retardation, megalocephaly, micrognathy, syndactyly, small tongue, hypoplastic genitalia, gynecomasty, obesity, and slight left body hemiatrophy. Neurologically the patient has had hypotonia of the lower limbs, cerebellar dysfunction including horizontal nystagmus, bilateral intention tremor, dysdiadokokinesia, gait ataxia. The clinical investigation revealed low plasma cholesterol and hypoplasia of the vermis in MRI. The epileptic phenomena were intractable and polymorphous. One should have thought that this is an unusual case of Smith-Lemli-Opitz syndrome associated with features of Joubert syndrome.


Asunto(s)
Cerebelo/fisiopatología , Discapacidad Intelectual/complicaciones , Síndrome de Smith-Lemli-Opitz/patología , Síndrome de Smith-Lemli-Opitz/fisiopatología , Adolescente , Colesterol/metabolismo , Humanos , Discapacidad Intelectual/patología , Discapacidad Intelectual/fisiopatología , Imagen por Resonancia Magnética/métodos , Masculino , Síndrome de Smith-Lemli-Opitz/metabolismo
11.
Qual Life Res ; 15(5): 833-9, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16721643

RESUMEN

This study is presenting the translation and cultural adaptation into Greek of the Quality of Life in Epilepsy Inventory (QOLIE-31). We adapted the QOLIE-31 to Greek through a procedure of translation-back-translation. Sixty-three patients were interviewed and completed the QOLIE-31 and the GHQ questionnaires. We re-examined a subset of them after a period of 2-5 weeks to evaluate the test-retest reliability of the questionnaire. We assessed the convergent validity by comparison of the QOLIE-31 and the GHQ and QOLIE-31 subscales and external measures. Discriminative validity was evaluated using the method of known-groups comparisons. The internal consistency was high for the QOLIE-31 and its' subscales (Cronbach's alpha 0.92 and 0.59-0.83 respectively). Test-retest reliability was acceptable (intra-class correlation coefficient 0.49-0.89 and Pearson's coefficient 0.53-0.92) for the group of patients who were re-examined. Comparison of the QOLIE-31 and GHQ scores showed agreement between the two questionnaires (Pearson's coefficient -0.61). We demonstrated the discriminative validity by the difference in the QOLIE-31 scores between patients with different seizure frequencies and different employment status. We concluded that the Greek version of the QOLIE-31 has psychometric properties equivalent to those of the original American-English version and is a valid and reliable instrument.


Asunto(s)
Epilepsia/psicología , Calidad de Vida , Encuestas y Cuestionarios , Adolescente , Adulto , Anciano , Anticonvulsivantes , Femenino , Grecia , Humanos , Masculino , Persona de Mediana Edad , Psicometría
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