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1.
Small ; : e2000421, 2020 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-32227457

RESUMO

The electrochemical N2 reduction reaction (NRR) is emerging as a promising alternative to the industrial Haber-Bosch process for distributed and modular production of NH3 . Nevertheless, developing high-efficiency catalysts to simultaneously realize both high activity and selectivity for the development of a sustainable NRR is very critical but extremely challenging. Here, a unique plasma-assisted strategy is developed to synthesize iridium diphosphide nanocrystals with abundant surface step atoms anchored in P,N-codoped porous carbon nanofilms (IrP2 @PNPC-NF), where the edges of the IrP2 nanocrystals are extremely irregular, and the ultrathin PNPC-NF possesses a honeycomb-like macroporous structure. These characteristics ensure that IrP2 @PNPC-NF delivers superior NRR performance with an NH3 yield rate of 94.0 µg h-1 mg-1 cat. and a faradaic efficiency (FE) of 17.8%. Density functional theory calculations reveal that the unique NRR performance originates from the low-coordinate step atoms on the edges of IrP2 nanocrystals, which can lower the reaction barrier to improve the NRR activity and simultaneously inhibit hydrogen evolution to achieve a high FE for NH3 formation. More importantly, such a plasma-assisted strategy is general and can be extended to the synthesis of other high-melting-point noble-metal phosphides (OsP2 @PNPC-NF, Re3 P4 @PNPC-NF, etc.) with abundant step atoms at lower temperatures.

2.
Proc Natl Acad Sci U S A ; 117(12): 6640-6650, 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32161124

RESUMO

The programmed cell death 1 (PD-1) receptor on the surface of immune cells is an immune checkpoint molecule that mediates the immune escape of tumor cells. Consequently, antibodies targeting PD-1 have shown efficacy in enhancing the antitumor activity of T cells in some types of cancers. However, the potential effects of PD-1 on tumor cells remain largely unknown. Here, we show that PD-1 is expressed across a broad range of tumor cells. The silencing of PD-1 or its ligand, PD-1 ligand 1 (PD-L1), promotes cell proliferation and colony formation in vitro and tumor growth in vivo. Conversely, overexpression of PD-1 or PD-L1 inhibits tumor cell proliferation and colony formation. Moreover, blocking antibodies targeting PD-1 or PD-L1 promote tumor growth in cell cultures and xenografts. Mechanistically, the coordination of PD-1 and PD-L1 activates its major downstream signaling pathways including the AKT and ERK1/2 pathways, thus enhancing tumor cell growth. This study demonstrates that PD-1/PD-L1 is a potential tumor suppressor and potentially regulates the response to anti-PD-1/PD-L1 treatments, thus representing a potential biomarker for the optimal cancer immunotherapeutic treatment.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32198805

RESUMO

N6 -isopentenyladenosine (i6 A) is an RNA modification found in cytokinins, which regulate plant growth/differentiation, and a subset of tRNAs, where it improves the efficiency and accuracy of translation. The installation and removal of this modification is mediated by prenyltransferases and cytokinin oxidases, and a chemical approach to selective deprenylation of i6 A has not been developed. We show that a selected group of oxoammonium cations function as artificial deprenylases to promote highly selective deprenylation of i6 A in nucleosides, oligonucleotides, and live cells. Importantly, other epigenetic modifications, amino acid residues, and natural products were not affected. Moreover, a significant phenotype difference in the Arabidopsis thaliana shoot and root development was observed with incubation of the cation. These results establish these small organic molecules as direct chemical regulators/artificial deprenylases of i6 A.

4.
Sci Rep ; 10(1): 4672, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32170105

RESUMO

Gastric carcinoma (GC) refers to a common digestive system disease that exhibits a very high incidence. MicroRNA hsa-mir-3923 belongs to a type of miRNA, of which the function has been merely investigated in breast, pancreatic cancers and pre-neoplasic stages of gastric cancer. It has not been studied or reported in gastric carcinoma, so the relationship between gastric hsa-mir-3923 expression and the clinics feature and pathology of GC cases was examined. This study employed data mining for analyzing gastric carcinoma data in The Cancer Genome Atlas database. A Chi squared test was performed for assessing the relations of hsa-mir-3923 expression with clinics-related and pathology-regulated variables. This study conducted the assessment of the role of hsa-mir-3923 in prognostic process using Kaplan-Meier curves, Receiver operating characteristic (ROC) analysis and proportional hazards model (Cox) study. With the use of Gene Expression Omnibus, this study carried out gene set enrichment analysis (GSEA). In the meantime, the common miRNA database was compared to predict potential target genes; as revealed by co-expression analysis, a regulatory network probably existed, containing hsa-mir-3923. For the analysis of the most tightly associated cytological behavior and pathway in GC, this study adopted the databases for Annotation, Visualization and Integrated Discovery (David) and KO-Based Annotation System (KOBAS). Cytoscape, R and STRING were employed for mapping probable regulatory networks displaying relations to hsa-mir-3923. Lastly, we obtained 69 genes most tightly associated with hsa-mir-3923 and described their relationship with Circos plot. As revealed from the results, hsa-mir-3923 displayed up-regulation in gastric carcinoma, and it displayed associations with vital status, N stage and histologic grade when being expressed. The predicted results of miRNA target genes suggested that there may be a close relationship between 66 genes and hsa-mir-3923 in gastric cancer. As indicated from co-expression data, a small regulating network of 4 genes probably existed. Our results elucidated that hsa-mir-3923 high-expression reveals poor prognosis of GC patients.

5.
Sci Rep ; 10(1): 5161, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32198434

RESUMO

Serum microRNAs (miRNAs) have been reported as novel biomarkers for various diseases. But circulating biomarkers for predicting the radiosensitivity of nasopharyngeal carcinoma (NPC) have not been used in clinical practice. To screen out of differently expressed serum miRNAs from NPC patients with different radiosensitivity may be helpful for its individual therapy. NPC patients with different radiosensitivity were enrolled according to the inclusion and exclusion criteria. RNA was isolated from serum of these NPC patients before treatment. We investigated the differential miRNA expression profiles using microarray test (GSE139164), and the candidate miRNAs were validated by reverse transcription-quantitative real time polymerase chain reaction (RT-qPCR) experiments. Receiver operating characteristic (ROC) analysis has been applied to estimate the diagnostic value. In this study, 37 serum-specific miRNAs were screened out from 12 NPC patients with different radiosensitivity by microarray test. Furthermore, RT-qPCR analysis confirmed that hsa-miR-1281 and hsa-miR-6732-3p were significantly downregulated in the serum of radioresistant NPC patients (P < 0.05), which was consistent with the results of microarray test. ROC curves demonstrated that the AUC for hsa-miR-1281 was 0.750 (95% CI: 0.574-0.926, SE 87.5%, SP 57.1%). While the AUC for hsa-miR-6732-3p was 0.696 (95% CI: 0.507-0.886, SE 56.3%, SP 78.6%). These results suggested that hsa-miR-1281 and hsa-miR-6732-3p in serum might serve as potential biomarkers for predicting the radiosensitivity of NPC.

6.
Eat Weight Disord ; 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32180210

RESUMO

OBJECTIVE: The aim of this study was to investigate how obesity was covered in Chinese newspapers from 1999 to 2018, demonstrating the trends and the characteristics of obesity-related news. METHODS: Content analysis was conducted to analyze a total of 358 news articles spanning two decades (1999-2018). We explored how Chinese newspapers portrayed obesity in terms of the evidence/sources cited in articles, its impacts, drivers/causes, and solutions; and how such portrayals have evolved over time. We further compared the articles across different types of newspapers (government-sponsored vs. commercial), two subpopulations (children vs. adults), and periods of time (1999-2008 vs. 2009-2018). RESULTS: Results showed that medical experts' interviews and statistics were the two most cited types of evidence in the articles. When discussing causes and solutions of obesity, factors pertaining to personal lifestyles were mentioned most frequently. Compared to psychological and social impacts, physical health risk was stressed more often. Compared with commercial newspapers, government-funded newspapers mentioned societal drivers of obesity and suggested reforming schools more frequently. Such differences were also found between coverage of child obesity and adult obesity. Our research, furthermore, revealed significant differences of media coverage of obesity across the two decades. CONCLUSIONS: Our findings indicate that obesity was generally depicted as a "self-regulated epidemic" in Chinese newspapers. Although the revealed causes and consequences of obesity are evidently related to individual factors, more attention should be directed to the roles that the government, media, and the society can play in preventing obesity and mitigating related social/economic burden. LEVEL OF EVIDENCE: Level V, cross-sectional descriptive study.

7.
Sci Rep ; 10(1): 3576, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32107418

RESUMO

Endometrial cancer (EC) is the sixth most common cancer in women. Since early EC has a good prognosis, identifying methods for early diagnosis is valuable. Here, we aimed to study the role of HDAC6, which has been indicated important in many kinds of cancers, in EC diagnosis and therapy. First, the expression levels of HDAC6 in EC tissues and cells were measured by qRT-PCR and Western blotting, and through bioinformatics and dual luciferase assays, HDAC6 was found to be a direct target of miR-206. Then, CCK-8, colony formation, wound healing, and Transwell assays were performed; these results indicated that HDAC6 promoted EC cell proliferation, metastasis and invasion, while miR-206 produced the opposite effects. In addition, rescue assays verified that the effect of miR-206 could be reversed by HDAC6, and global gene expression analysis confirmed the relationship between miR-206 and HDAC6. Finally, we measured the levels of PTEN, p-AKT and p-mTOR and other key molecules and speculated that miR-206 might target HDAC6 to suppress EC progression via the PTEN/AKT/mTOR pathway. In conclusion, downregulation of miR-206 and upregulation of HDAC6 in EC may predict poor prognosis, and as the target gene of miR-206, HDAC achieves its carcinogenic effect through the PTEN/AKT/mTOR pathway.

8.
Artigo em Inglês | MEDLINE | ID: mdl-32079407

RESUMO

Recombinant forms contribute substantially to the genetic diversity of HIV-1. Recent studies have also revealed that three major viral strains (CRF07_BC, CRF01_AE, and subtype B) have been cocirculating among men who have sex with men (MSM) in Anhui, suggesting a high probability of generating new recombinants. In this study, we reported a novel CRF01_AE and CRF07_BC HIV-1 recombinant form in MSM in Fuyang city of China. Two near full-length genome (NFLG) named FY184 and FY208 were successfully obtained. The genomic composition analysis of the NFLG reveals that it was divided into four segments by three breakpoints, with two regions of CRF07_BC inserted into a CRF01_AE backbone's gag and pol regions. The CRF01_AE regions were originated from a subcluster lineage of CRF01_AE, which is mainly circulating among MSM in China. The emergence of a novel recombinant of CRF01_AE/CRF07_BC is indicative of the increasing genetic diversity of the HIV epidemic in MSM in Anhui.

9.
Biol Psychol ; 150: 107844, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31954187

RESUMO

The goal of this study was to examine whether the links between Chinese college students' parental attachment, peer attachment, and prosocial behaviors were moderated by a physiological factor-baseline respiratory sinus arrhythmia (RSA). The simplified version of the Inventory of Parental and Peer Attachment (IPPA-R) and the Chinese version of the Prosocial Tendencies Measure (PTM-R) were administered to one hundred forty-four undergraduate students (M = 18.96 years, SD = 1.06 years; 30 % men) to assess parental and peer attachment and prosocial behaviors. Baseline RSA was calculated by electrocardiogram (ECG) data collected during a resting period in the laboratory. The results showed that both parental and peer attachment were positively associated with college students' global prosocial behaviors. Moreover, peer attachment interacted with baseline RSA to predict college students' global prosocial behaviors. Specifically, peer attachment was positively related to global prosocial behaviors among college students with low baseline RSA, while peer attachment was not related to global prosocial behaviors among college students with high baseline RSA. In addition, the examination with submeasures of prosocial behaviors revealed that parental and peer attachment and their interaction with baseline RSA have different effects on these different types of prosocial behaviors. The current findings highlight the importance of the consideration of psychosocial factors in conjunction with physiological factors to predict college students' prosocial behaviors.

10.
Plant Biotechnol J ; 18(2): 364-372, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31254434

RESUMO

Traditional approaches for sequencing insertion ends of bacterial artificial chromosome (BAC) libraries are laborious and expensive, which are currently some of the bottlenecks limiting a better understanding of the genomic features of auto- or allopolyploid species. Here, we developed a highly efficient and low-cost BAC end analysis protocol, named BAC-anchor, to identify paired-end reads containing large internal gaps. Our approach mainly focused on the identification of high-throughput sequencing reads carrying restriction enzyme cutting sites and searching for large internal gaps based on the mapping locations of both ends of the reads. We sequenced and analysed eight libraries containing over 3 200 000 BAC end clones derived from the BAC library of the tetraploid potato cultivar C88 digested with two restriction enzymes, Cla I and Mlu I. About 25% of the BAC end reads carrying cutting sites generated a 60-100 kb internal gap in the potato DM reference genome, which was consistent with the mapping results of Sanger sequencing of the BAC end clones and indicated large differences between autotetraploid and haploid genotypes in potato. A total of 5341 Cla I- and 165 Mlu I-derived unique reads were distributed on different chromosomes of the DM reference genome and could be used to establish a physical map of target regions and assemble the C88 genome. The reads that matched different chromosomes are especially significant for the further assembly of complex polyploid genomes. Our study provides an example of analysing high-coverage BAC end libraries with low sequencing cost and is a resource for further genome sequencing studies.

11.
Talanta ; 207: 120310, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594599

RESUMO

Recently, superficially porous particles (SPPs) have been intensively studied and employed for highly efficient and fast separations. In this paper, the SiO2@SiO2 SPPs were synthesized by an improved polymerization-induced colloid aggregation (PICA) method using urea-formaldehyde polymer as the template. The agglomeration of silica core during modification with ureidopropyltrimethoxysilane (UPS) can not only be avoided by reflux in neutral ethanol solution, but also the secondary nucleation of the colloidal silica sol can be inhibited via optimizing the reaction conditions including pH, temperature, colloidal silica sol concentration and the reaction time. The shell thickness and pore size of SPPs can be controlled successfully by adjusting the weight ratio of silica core/colloidal silica sol and the particle size of colloidal silica sol, respectively. The SPP-C18 columns packed using octadecyltrichlorosilane (ODS) modified SPPs with different pore sizes were employed to separate small solutes and proteins. The baseline separations of 6 kinds of alkyl benzenes and 5 kinds of aromatic alcohol homologues were achieved within 4 min by the SPP-C18 column with 8 nm pore size. Compared with the commercial BEH-C18 column, more than 50,000/m of the plate number of propylbenzene was obtained, and the former provided higher column efficiency to separate small solutes than the latter. Meanwhile, 6 kinds of proteins were also separated completely within 2 min using the SPP-C18 column with 40 nm pore size. In addition, the SPP-C18 capillary column was applied to separate and identify the BSA/HeLa/mouse liver digests with capillary LC-MSMS, respectively. The results indicate that more proteins and peptides can be identified using SPP-C18 capillary column compared with commercial silica-C18 capillary column. The result demonstrates that the prepared SPP-C18 column provides higher column efficiency and the SPPs synthesized with the improved PICA method shows a great potential application for the fast separation of small solutes and proteins.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Microesferas , Polimerização , Proteínas/isolamento & purificação , Dióxido de Silício/química , Animais , Coloides , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Porosidade , Pressão , Temperatura , Fatores de Tempo
12.
Invest Ophthalmol Vis Sci ; 60(15): 4966-4971, 2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31790559

RESUMO

Purpose: To describe the 6-year incidence of early and late age-related macular degeneration (AMD) and its associated factors in a representative large rural Chinese population. Methods: A population-based longitudinal study was conducted in rural China from 2006 to 2007. In total, 6830 persons aged 30 years or older participated in the study. The 6-year follow-up study was performed between 2012 and 2013. The modified Wisconsin Age-Related Maculopathy Grading System (WARMGS) protocol in the Blue Mountains Eye Study was used as the AMD grading standard. Results: Excluding 509 deceased subjects, 5394 (follow-up rate 85.3%) completed the follow-up. Among them, 5048 participants had gradable photographs of at least one eye at both examinations. The incidence of early and late AMD over 6 years was 4.2% (95% CI, 3.8%-4.7%) and 0.2% (95% CI, 0.2%-0.3%), respectively. In the multivariable analysis, per-year increase in age (P < 0.001; OR = 1.06; 95% CI, 1.04-1.07), male sex (P = 0.006; OR = 0.64; 95% CI, 0.47-0.88), and per-millimeter increase in axial length (P = 0.010; OR = 0.78; 95% CI, 0.63-0.94) at baseline were significantly associated with incident early AMD. Early AMD was not associated with systolic blood pressure, diastolic blood pressure, hypertension, diabetes, history of stroke, history of heart disease, body mass index, total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, triglycerides, smoking status, refractive error, or corneal curvature radius. There were too few cases of late AMD for a valid statistical analysis of the risk factors. Conclusions: The incidence of early and late AMD over 6 years in a rural Chinese population was 4.2% (95% CI, 3.8%-4.7%) and 0.2% (95% CI, 0.2%-0.3%), respectively. Age, sex, and axial length are relevant risk factors for early AMD in rural China.


Assuntos
Degeneração Macular/epidemiologia , Vigilância da População/métodos , Medição de Risco , População Rural , China/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
14.
J Org Chem ; 84(24): 16323-16328, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31729221

RESUMO

Tricyclic carbazole is an important scaffold in many naturally occurring metabolites, as well as valuable building blocks. Here we report the reconstitution of the ring A formation of the bacterial neocarazostatin A carbazole metabolite. We provide evidence of the involvement of two unusual aromatic polyketide proteins. This finding suggests how new enzymatic activities can be recruited to specific pathways to expand biosynthetic capacities. Finally, we leveraged our bioinformatics survey to identify the untapped capacity of carbazole biosynthesis.

15.
J Phys Chem B ; 123(48): 10224-10232, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31693366

RESUMO

We have developed a scheme to compute the standard potential of the Ag/AgCl reference electrode using density functional theory-based molecular dynamics, similar to the computational standard hydrogen electrode (SHE) developed by Cheng, Sulpizi, and Sprik [J. Chem. Phys. 2009, 131, 154504], with which our new computational reference electrode was compared. We have obtained a similar value of the potential of the Ag/AgCl electrode versus SHE to the experiment. The newly developed computational reference electrode will be extended to nonaqueous solvents in the future, where it will be used to predict standard equilibrium potentials to be compared with experimental data.

17.
Chin Med J (Engl) ; 132(18): 2157-2167, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31490265

RESUMO

BACKGROUND: Handan Eye Study (HES), a large population-based cohort study in rural area of northern China, was one of the few studies focusing on the major eye diseases of rural Chinese population. The aim of this study was to introduce the design, methodology and to assess the data quality of the follow-up phase of HES. METHODS: All participants were recruited in Yongnian county of Handan city between 2012 and 2013. Main outcomes were measured by visual quality scales and ocular examinations. We performed the Chi-square test to make comparison of categorical data among groups, One-way analysis of variance and Kruskal-Wallis test was applied to make comparison of continuous data among groups, a post-hoc test was done to make further pairwise comparison. Inter-class correlation coefficients (ICCs) and Kappa coefficients were used to evaluate the consistency between different operators. Logistic regression was used to explore the influence factors of death, odds ratio (OR) and 95% confidence interval (CI) were used to estimate the effect size of each influence factor. RESULTS: The follow-up rate was 85.3%. Subjects were classified into three groups: the follow-up group (n = 5394), the loss to follow-up group (n = 929), and the dead group (n = 507), comparison of their baseline information was done. Compared with the other two groups, age of the dead group (66.52 ±â€Š10.31 years) was the oldest (Z = 651.293, P < 0.001), male proportion was the highest (59.0%) (χ = 42.351, P < 0.001), only 65.9% of the dead finished middle school education (Z = 205.354, P < 0.001). The marriage percentage, body mass index (BMI), best-corrected visual acuity (BCVA), and intra-ocular pressure of the dead group was the lowest either. Spherical equivalent error (SER) of the dead group was the highest. Besides, history of smoking, hypertension, diabetes, and heart disease were more common in the dead group. Multivariate analysis showed that age (OR = 1.901, 95% CI: 1.074-1.108), gender (OR = 0.317, 95% CI: 0.224-0.448), and BCVA (OR = 0.282, 95% CI: 0.158-0.503) were associated with death. While between the follow-up group and the loss to follow-up group, there was only difference on age, gender, BMI, systolic blood pressure and SER. The Cronbach coefficients of all scales used in the follow-up were ≥0.63 and the cumulative variances were ≥0.61, indicating good reliability and validity. The ICCs and Kappa coefficients between different operators were ≥0.69. CONCLUSIONS: HES has a high follow-up rate and a low risk of loss to follow-up bias. Age, gender, and BCVA are influence factors of death. Specifically, male subjects are at a higher risk of death than female, age is a risk factor of death while BCVA is a protective factor for death.

18.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(8): 809-812, 2019 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-31400134

RESUMO

OBJECTIVE: To explore the clinical features of a Chinese pedigree affected with skeletal muscle sodium channelopathies due to variation of SCN4A gene. METHODS: Potential variation of the 24 exons of the SCN4A gene was screened using PCR and Sanger sequencing. RESULTS: Four family members were affected with the disease in an autosomal dominant inheritance pattern. Three patients had normekalemic periodic paralysis, while 1 showed paramyotonia congenita. Genetic analysis detected a missense variation c.2078T>C (p.Ile693Thr) in exon 13 of the SCN4A gene in the proband and other 3 affected relatives. CONCLUSION: Normokalemic periodic paralysis and paramyotonia congenita can occur in different family members with skeletal muscle sodium channelopathies due to c.2078T>C(p.Ile693Thr) variation of SCN4A gene.


Assuntos
Canalopatias/genética , Músculo Esquelético/fisiopatologia , Canal de Sódio Disparado por Voltagem NAV1.4/genética , Humanos , Mutação , Linhagem
19.
Physiol Meas ; 40(9): 095004, 2019 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-31443095

RESUMO

Epilepsy is a common neurological disorder which can occur in people of all ages globally. For the clinical treatment of epileptic patients, the detection of epileptic seizures is of great significance. OBJECTIVE: Electroencephalography (EEG) is an essential component in the diagnosis of epileptic seizures, from which brain surgeons can detect important pathological information about patient epileptiform discharges. This paper focuses on adaptive seizure detection from EEG recordings. We propose a new feature extraction model based on an adaptive decomposition method, named intrinsic time-scale decomposition (ITD), which is suitable for analyzing non-linear and non-stationary data. APPROACH: Firstly, using the ITD technique, every EEG recording is decomposed into several proper rotation components (PRCs). Secondly, the instantaneous amplitudes and frequencies of these PRCs can be calculated and then we extract their statistical indices. Furthermore, we combine all these statistical indices of the corresponding five PRCs as the feature vector of each EEG signal. Finally, these feature vectors are fed into a feedforward neural network (FNN) classifier for EEG classification. The whole process of feature extraction proposed in this paper only involves one parameter and the role of the ITD method is based on a piecewise linear function, which makes the computation of the model simple and fast. More useful information for classification can be obtained since we take advantage of both instantaneous amplitude and instantaneous frequency for feature extraction. MAIN RESULTS: We consider the 17 classification problems which contain normal versus epileptic, non-seizure versus seizure and normal versus interictal versus ictal using a FNN classifier which only contains one hidden layer. Experimental results show that the proposed method can catch the discriminative features of EEG signals and obtain comparable results when compared with state-of-the-art detection methods. SIGNIFICANCE: Therefore, the proposed system has a great potential in real-time seizure detection and provides physicians with a real-time diagnostic aid in their practice.

20.
Subst Use Misuse ; 54(13): 2127-2133, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31290365

RESUMO

Background: Many research studies reveal that both attentional bias and impaired cognitive control significantly influence heroin addiction. However, limited research has been conducted into how the interplay between attentional bias and cognitive control modulates heroin-seeking behavior. Objectives: A modified version of the flanker task was used to investigate whether attentional bias to drug-related stimuli is modulated by cognitive control mechanisms among heroin users. Methods: Sixty participants (30 male heroin users during their abstinence period and 30 normal controls) responded to the direction of the middle arrow, while ignoring the adjacent arrow and the pictures (drug-related cues and neutral cues) presented as part of the task. Results: The abstinent heroin users had a significantly larger flanker effect under drug-related cues compared to neutral cues, whereas the control group showed no such trend. This effect was primarily influenced by increased reaction times in the presence of drug-related cues relative to neutral cues in the incongruent condition among abstinent heroin users, but not in the control group. Conclusions/Importance: Among abstinent heroin users, attentional bias to drug-related cues was moderated by attentional control. Further, high cognitive control demand was found to reduce heroin users' ability to resist attentional capture from salient, but irrelevant, drug-related information, which may contribute to compulsive drug-seeking behavior and relapse in heroin users.

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