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2.
Comput Intell Neurosci ; 2021: 6694310, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33628218

RESUMO

Tactile perception, the primary sensing channel of the tactile brain-computer interface (BCI), is a complicated process. Skin friction plays a vital role in tactile perception. This study aimed to examine the effects of skin friction on tactile P300 BCI performance. Two kinds of oddball paradigms were designed, silk-stim paradigm (SSP) and linen-stim paradigm (LSP), in which silk and linen were wrapped on target vibration motors, respectively. In both paradigms, the disturbance vibrators were wrapped in cotton. The experimental results showed that LSP could induce stronger event-related potentials (ERPs) and achieved a higher classification accuracy and information transfer rate (ITR) compared with SSP. The findings indicate that high skin friction can achieve high performance in tactile BCI. This work provides a novel research direction and constitutes a viable basis for the future tactile P300 BCI, which may benefit patients with visual impairments.

3.
Int J Neural Syst ; : 2150004, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33438531

RESUMO

Tactile P300 brain-computer interface (BCI) generally has a worse accuracy and information transfer rate (ITR) than the visual-based BCI. It may be due to the fact that human beings have a relatively poor tactile perception. This study investigated the influence of visual attention on the performance of a tactile P300 BCI. We designed our paradigms based on a novel cheeks-stim paradigm which attached the stimulators on the subject's cheeks. Two paradigms were designed as follows: a paradigm with no visual attention and another paradigm with visual attention to the target position. Eleven subjects were invited to perform the two paradigms. We also recorded and analyzed the eyeball movement data during the paradigm with visual attention to explore whether the eyeball movement would have an effect on the BCI classification. The average online accuracy was 89.09% for the paradigm with visual attention, which was significantly higher than that of the paradigm with no visual attention (70.45%). Significant difference in ITR was also found between the two paradigms ([Formula: see text]). The results demonstrated that visual attention was an effective method to improve the performance of tactile P300 BCI. Our findings suggested that it may be feasible to complete an efficient tactile BCI system by adding visual attention.

4.
Heart Surg Forum ; 23(6): E733-E739, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33234210

RESUMO

BACKGROUND: There is still a paucity of data on the efficacy of non-vitamin K antagonist oral anticoagulants (NOACs) in the prevention of left atrial thrombus (LAT) formation before cardioversion or catheter ablation. To assess the efficacy of NOACs in the prevention of LAT in patients with non-valvular atrial fibrillation (NVAF) compared with vitamin K antagonists (VKAs), we conducted a meta-analysis. METHODS: We searched PubMed, Embase, and the Cochrane Library databases. For meta-analysis, dichotomous variables were analyzed by using the odds ratios (OR) computed using the Mantel Haenszel method (random models). All results were reported with 95% confidence intervals (CI). RESULTS: A total of 13 studies (one randomized controlled investigation and 12 observational studies) were included in the meta-analysis. There was no statistically significant difference between the NOACs and VKAs groups with respect to the odds of LAT/LAAT formations (OR 0.79; 95% CI: 0.52-1.21; P = .29; (I2 = 14%). CONCLUSIONS: NOACs were as effective as VKAs in the prevention of LAT/LAAT formation in patients with NVAF. Though patients on NOACs therapy showed a lower incidence of LAT/LAAT formation compared with VKAs, it was not significant (P = .29).

5.
IEEE Trans Neural Syst Rehabil Eng ; 28(10): 2153-2163, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32870796

RESUMO

The performance of motor imagery (MI) based Brain-computer interfacing (BCI) is easily affected by noise and redundant information that exists in the multi-channel electroencephalogram (EEG). To solve this problem, many temporal and spatial feature based channel selection methods have been proposed. However, temporal and spatial features do not accurately reflect changes in the power of the oscillatory EEG. Thus, spectral features of MI-related EEG signals may be useful for channel selection. Bispectrum analysis is a technique developed for extracting non-linear and non-Gaussian information from non-linear and non-Gaussian signals. The features extracted from bispectrum analysis can provide frequency domain information about the EEG. Therefore, in this study, we propose a bispectrum-based channel selection (BCS) method for MI-based BCI. The proposed method uses the sum of logarithmic amplitudes (SLA) and the first order spectral moment (FOSM) features extracted from bispectrum analysis to select EEG channels without redundant information. Three public BCI competition datasets (BCI competition IV dataset 1, BCI competition III dataset IVa and BCI competition III dataset IIIa) were used to validate the effectiveness of our proposed method. The results indicate that our BCS method outperforms use of all channels (83.8% vs 69.4%, 86.3% vs 82.9% and 77.8% vs 68.2%, respectively). Furthermore, compared to the other state-of-the-art methods, our BCS method also can achieve significantly better classification accuracies for MI-based BCI (Wilcoxon signed test, p < 0.05).

6.
Int J Pediatr Otorhinolaryngol ; 136: 110172, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32580110

RESUMO

Waardenburg Syndrome (WS) is a condition characterized by sensorineural deafness and pigment disturbances of the skin, hair and iris. By using the latest genomics technology, the WS-related gene mutations and corresponding mechanisms have been widely studied and reported. and the high genetic heterogeneity of the disease has also been explained. However, the SOX10 gene transcription and expression has still be unclear. In this study, we determined the phenotypic gene expression of WS patients in two Chinese WS families. More importantly, we identified two novel SOX10 mutations, c.482-487del (p.R161-M162del)and c.52G > T (p.E18X) in WSII for the first time in the Chinese population.

7.
Front Neurosci ; 14: 54, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32082118

RESUMO

Objective: Previous studies have shown that combing with color properties may be used as part of the display presented to BCI users in order to improve performance. Build on this, we explored the effects of combinations of face stimuli with three primary colors (RGB) on BCI performance which is assessed by classification accuracy and information transfer rate (ITR). Furthermore, we analyzed the waveforms of three patterns. Methods: We compared three patterns in which semitransparent face is overlaid three primary colors as stimuli: red semitransparent face (RSF), green semitransparent face (GSF), and blue semitransparent face (BSF). Bayesian linear discriminant analysis (BLDA) was used to construct the individual classifier model. In addition, a Repeated-measures ANOVA (RM-ANOVA) and Bonferroni correction were chosen for statistical analysis. Results: The results indicated that the RSF pattern achieved the highest online averaged accuracy with 93.89%, followed by the GSF pattern with 87.78%, while the lowest performance was caused by the BSF pattern with an accuracy of 81.39%. Furthermore, significant differences in classification accuracy and ITR were found between RSF and GSF (p < 0.05) and between RSF and BSF patterns (p < 0.05). Conclusion: The semitransparent faces colored red (RSF) pattern yielded the best performance of the three patterns. The proposed patterns based on ERP-BCI system have a clinically significant impact by increasing communication speed and accuracy of the P300-speller for patients with severe motor impairment.

8.
IEEE Trans Neural Syst Rehabil Eng ; 28(1): 3-12, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31794401

RESUMO

P300-based brain-computer interfaces (BCIs) provide an additional communication channel for individuals with communication disabilities. In general, P300-based BCIs need to be trained, offline, for a considerable period of time, which causes users to become fatigued. This reduces the efficiency and performance of the system. In order to shorten calibration time and improve system performance, we introduce the concept of a generic model set. We used ERP data from 116 participants to train the generic model set. The resulting set consists of ten models, which are trained by weighted linear discriminant analysis (WLDA). Twelve new participants were then invited to test the validity of the generic model set. The results demonstrated that all new participants matched the best generic model. The resulting mean classification accuracy equaled 80% after online training, an accuracy that was broadly equivalent to the typical training model method. Moreover, the calibration time was shortened by 70.7% of the calibration time of the typical model method. In other words, the best matching model method only took 81s to calibrate, while the typical model method took 276s. There were also significant differences in both accuracy and raw bit rate between the best and the worst matching model methods. We conclude that the strategy of combining the generic models with online training is easily accepted and achieves higher levels of user satisfaction (as measured by subjective reports). Thus, we provide a valuable new strategy for improving the performance of P300-based BCI.


Assuntos
Interfaces Cérebro-Computador , Eletroencefalografia/métodos , Potencial Evocado P300 , Adolescente , Algoritmos , Calibragem , Análise Discriminante , Feminino , Voluntários Saudáveis , Humanos , Aprendizado de Máquina , Masculino , Modelos Estatísticos , Adulto Jovem
9.
Med Hypotheses ; 81(5): 931-5, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24021617

RESUMO

Essential hypertension is a major risk factor for cardiovascular morbidity and mortality, and the early-diagnosis is very important for the prevention of essential hypertension. Previously, we found that Pin1, the only known enzyme isomerizing pSer/pThr-Pro motifs in proteins, may gradually become inactive under conditions of stress such as intracellular acidification and fever. Interestingly, essential hypertension and the dysfunction of Pin1 often synchronously occur with the increasing age. Recent evidence indicates that Pin1 primarily increases the activity of endothelial nitric oxide synthase (eNOS) and the production of nitric oxide (NO) in multiple ways, significantly promoting the relaxation response of blood vessels and preventing the elevation of blood pressure. Further, the inhibition of Pin1 results in significantly increased blood pressure in rats. So, we hypothesized and evaluated the potential of Pin1 to be a new early-diagnostic biomarker as well as a therapeutic drug for essential hypertension. The unique activity of Pin1 and some epidemiological and experimental data evidence that the decreased activity of Pin1 may be closely associated with the development of essential hypertension. The factors that may impact the activity of Pin1 and correlate with the risk of essential hypertension were also discussed. These findings indicate that Pin1 plays a key and permanent role in efficiently preventing the development of essential hypertension, and that Pin1 may be a promising early-diagnostic biomarker as well as an effective therapeutic drug for the early-diagnosis, prevention, and treatment of essential hypertension, potentially decreasing the risk of cardiovascular morbidity and mortality.


Assuntos
Biomarcadores/metabolismo , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Modelos Biológicos , Peptidilprolil Isomerase/uso terapêutico , Vasodilatadores/metabolismo , Fatores Etários , Hipertensão Essencial , Humanos , Peptidilprolil Isomerase de Interação com NIMA , Óxido Nítrico Sintase Tipo III/metabolismo , Peptidilprolil Isomerase/metabolismo
10.
Med Hypotheses ; 81(2): 282-4, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23648381

RESUMO

A new molecular mechanism is proposed to explain the opposite effects of fever on cancers and Alzheimer's disease (AD). The proposal is based on the experimental discovery that the fever stress interferes the structure and the activity of Pin1, which plays uniquely opposite roles in the pathogenesis of cancers and AD. Pin1 is the only known cis-trans isomerase that specifically isomerizes the pSer/pThr-Pro motifs in proteins, facilitating kinds of signaling pathways. The up-regulation of Pin1 can amplify multiple oncogenic signaling pathways, resulting in cancers, while the down-regulation of Pin1 can cause many pathological characteristics of AD. Recently, we found that Pin1 is sensitive to heat treatment, and heating can gradually damage both of the structure and the function of Pin1. So, we hypothesize that the fever stress, which is usually induced by febrile diseases or hyperthermia treatment, may lead to the damaged structure of Pin1 and the decreased activity of it in vivo, resulting in the decreased risk of cancers and the increased risk of AD. Numerous epidemiological and experimental researches on cancers and AD support the hypothesis. The hypothesis not only provides new insights into the opposite effects of fever on cancers and AD, but also gives new clues for understanding the interacting effects of the environmental and the genetic factors in the complicated pathogenesis of cancers and AD.


Assuntos
Doença de Alzheimer/fisiopatologia , Febre/fisiopatologia , Modelos Teóricos , Neoplasias/fisiopatologia , Peptidilprolil Isomerase/química , Peptidilprolil Isomerase/fisiologia , Doença de Alzheimer/complicações , Regulação para Baixo , Medicina Baseada em Evidências , Febre/complicações , Humanos , Peptidilprolil Isomerase de Interação com NIMA , Neoplasias/complicações , Transdução de Sinais , Regulação para Cima
12.
Tumour Biol ; 25(1-2): 62-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15192314

RESUMO

Tumour development and metastasis are associated with altered gene expression profiles. The aim of this study was to identify the transcriptional differences in normal, tumour and metastatic tissue. We used oligonucleotide arrays to identify differential expression patterns of insulin-like growth factor 2 (IGF 2) between 139 primary colorectal tumour specimens and 42 tumour-adjacent mucosa specimens from colorectal cancer (CRC) patients. The expression levels of the IGF 2 gene were significantly increased in primary tumours compared with adjacent mucosae. This was concordant with our real-time RT-PCR quantification of 48 matched tumour mucosa samples. IGF 2 expression levels were also measured by RT-PCR quantitative analysis in 18 liver metastases and 10 normal tissues from patients without cancer. The mRNA levels were significantly under-expressed in liver metastases compared with either colorectal tumours or adjacent normal mucosae. The non- malignant normal tissue expressed significantly lower IGF 2 levels than adjacent normal tissue, and this was not due to a field effect originating from the tumour. In addition, our microarray data demonstrated that IGF 2 expression was down-regulated in sporadic microsatellite instability (MSI-H) CRC and parallels under-expression of hMLH1 and IGF 2 receptor genes in these patients. We conclude that IGF 2 plays an important role in CRC development. Also, individuals with loss of genomic imprinting (LOI) causing over-expression of IGF 2 may be at greater risk of developing CRC. However, this LOI may be reversed in MSI-H patients.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Perfilação da Expressão Gênica , Predisposição Genética para Doença , Fator de Crescimento Insulin-Like II/biossíntese , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Análise de Sequência com Séries de Oligonucleotídeos , DNA de Neoplasias , Humanos , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Genética , Regulação para Cima
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