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1.
Proc Natl Acad Sci U S A ; 121(26): e2319322121, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38900789

RESUMEN

Thymocyte selection-associated high-mobility group box (TOX) is a transcription factor that is crucial for T cell exhaustion during chronic antigenic stimulation, but its role in inflammation is poorly understood. Here, we report that TOX extracellularly mediates drastic inflammation upon severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection by binding to the cell surface receptor for advanced glycation end-products (RAGE). In various diseases, including COVID-19, TOX release was highly detectable in association with disease severity, contributing to lung fibroproliferative acute respiratory distress syndrome (ARDS). Recombinant TOX-induced blood vessel rupture, similar to a clinical signature in patients experiencing a cytokine storm, further exacerbating respiratory function impairment. In contrast, disruption of TOX function by a neutralizing antibody and genetic removal of RAGE diminished TOX-mediated deleterious effects. Altogether, our results suggest an insight into TOX function as an inflammatory mediator and propose the TOX-RAGE axis as a potential target for treating severe patients with pulmonary infection and mitigating lung fibroproliferative ARDS.


Asunto(s)
COVID-19 , Receptor para Productos Finales de Glicación Avanzada , SARS-CoV-2 , Humanos , Receptor para Productos Finales de Glicación Avanzada/metabolismo , COVID-19/inmunología , COVID-19/metabolismo , COVID-19/patología , COVID-19/complicaciones , COVID-19/virología , Animales , Ratones , Inflamación/metabolismo , Inflamación/patología , Síndrome de Dificultad Respiratoria/inmunología , Síndrome de Dificultad Respiratoria/metabolismo , Síndrome de Dificultad Respiratoria/patología , Síndrome de Dificultad Respiratoria/virología , Lesión Pulmonar/inmunología , Lesión Pulmonar/metabolismo , Lesión Pulmonar/patología , Proteínas del Grupo de Alta Movilidad/metabolismo , Proteínas del Grupo de Alta Movilidad/genética , Masculino , Pulmón/patología , Pulmón/metabolismo , Pulmón/inmunología , Femenino
2.
BMC Med Inform Decis Mak ; 24(1): 50, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38355559

RESUMEN

BACKGROUND: This study was conducted to address the existing drawbacks of inconvenience and high costs associated with sleep monitoring. In this research, we performed sleep staging using continuous photoplethysmography (PPG) signals for sleep monitoring with wearable devices. Furthermore, our aim was to develop a more efficient sleep monitoring method by considering both the interpretability and uncertainty of the model's prediction results, with the goal of providing support to medical professionals in their decision-making process. METHOD: The developed 4-class sleep staging model based on continuous PPG data incorporates several key components: a local attention module, an InceptionTime module, a time-distributed dense layer, a temporal convolutional network (TCN), and a 1D convolutional network (CNN). This model prioritizes both interpretability and uncertainty estimation in its prediction results. The local attention module is introduced to provide insights into the impact of each epoch within the continuous PPG data. It achieves this by leveraging the TCN structure. To quantify the uncertainty of prediction results and facilitate selective predictions, an energy score estimation is employed. By enhancing both the performance and interpretability of the model and taking into consideration the reliability of its predictions, we developed the InsightSleepNet for accurate sleep staging. RESULT: InsightSleepNet was evaluated using three distinct datasets: MESA, CFS, and CAP. Initially, we assessed the model's classification performance both before and after applying an energy score threshold. We observed a significant improvement in the model's performance with the implementation of the energy score threshold. On the MESA dataset, prior to applying the energy score threshold, the accuracy was 84.2% with a Cohen's kappa of 0.742 and weighted F1 score of 0.842. After implementing the energy score threshold, the accuracy increased to a range of 84.8-86.1%, Cohen's kappa values ranged from 0.75 to 0.78 and weighted F1 scores ranged from 0.848 to 0.861. In the case of the CFS dataset, we also noted enhanced performance. Before the application of the energy score threshold, the accuracy stood at 80.6% with a Cohen's kappa of 0.72 and weighted F1 score of 0.808. After thresholding, the accuracy improved to a range of 81.9-85.6%, Cohen's kappa values ranged from 0.74 to 0.79 and weighted F1 scores ranged from 0.821 to 0.857. Similarly, on the CAP dataset, the initial accuracy was 80.6%, accompanied by a Cohen's kappa of 0.73 and weighted F1 score was 0.805. Following the application of the threshold, the accuracy increased to a range of 81.4-84.3%, Cohen's kappa values ranged from 0.74 to 0.79 and weighted F1 scores ranged from 0.813 to 0.842. Additionally, by interpreting the model's predictions, we obtained results indicating a correlation between the peak of the PPG signal and sleep stage classification. CONCLUSION: InsightSleepNet is a 4-class sleep staging model that utilizes continuous PPG data, serves the purpose of continuous sleep monitoring with wearable devices. Beyond its primary function, it might facilitate in-depth sleep analysis by medical professionals and empower them with interpretability for intervention-based predictions. This capability can also support well-informed clinical decision-making, providing valuable insights and serving as a reliable second opinion in medical settings.


Asunto(s)
Aprendizaje Profundo , Humanos , Incertidumbre , Fotopletismografía/métodos , Reproducibilidad de los Resultados , Sueño
3.
Sensors (Basel) ; 24(5)2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38475091

RESUMEN

In modern society, the popularity of wearable devices has highlighted the need for data security. Bio-crypto keys (bio-keys), especially in the context of wearable devices, are gaining attention as a next-generation security method. Despite the theoretical advantages of bio-keys, implementing such systems poses practical challenges due to their need for flexibility and convenience. Electrocardiograms (ECGs) have emerged as a potential solution to these issues but face hurdles due to intra-individual variability. This study aims to evaluate the possibility of a stable, flexible, and convenient-to-use bio-key using ECGs. We propose an approach that minimizes biosignal variability using normalization, clustering-based binarization, and the fuzzy extractor, enabling the generation of personalized seeds and offering ease of use. The proposed method achieved a maximum entropy of 0.99 and an authentication accuracy of 95%. This study evaluated various parameter combinations for generating effective bio-keys for personal authentication and proposed the optimal combination. Our research holds potential for security technologies applicable to wearable devices and healthcare systems.


Asunto(s)
Electrocardiografía , Dispositivos Electrónicos Vestibles , Seguridad Computacional
4.
Int J Mol Sci ; 25(6)2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38542468

RESUMEN

This study was performed to investigate the protective effects of Allium ochotense on fatty liver and hepatitis in chronic alcohol-induced hepatotoxicity. The physiological compounds of a mixture of aqueous and 60% ethanol (2:8, w/w) extracts of A. ochotense (EA) were identified as kestose, raffinose, kaempferol and quercetin glucoside, and kaempferol di-glucoside by UPLC Q-TOF MSE. The EA regulated the levels of lipid metabolism-related biomarkers such as total cholesterol, triglyceride, low-density lipoprotein (LDL), and high-density lipoprotein (HDL)-cholesterol in serum. Also, EA ameliorated the levels of liver toxicity-related biomarkers such as glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), and total bilirubin in serum. EA improved the antioxidant system by reducing malondialdehyde contents and increasing superoxide dismutase (SOD) levels and reduced glutathione content. EA improved the alcohol metabolizing enzymes such as alcohol dehydrogenase, acetaldehyde dehydrogenase, and cytochrome P450 2E1 (CYP2E1). Treatment with EA alleviated lipid accumulation-related protein expression by improving phosphorylation of AMP-activated protein kinase (p-AMPK) expression levels. Especially, EA reduced inflammatory response by regulating the toll-like receptor-4/nuclear factor kappa-light-chain-enhancer of activated B cells (TLR-4/NF-κB) signaling pathway. EA showed an anti-apoptotic effect by regulating the expression levels of B-cell lymphoma 2 (BCl-2), BCl-2-associated X protein (BAX), and caspase 3. Treatment with EA also ameliorated liver fibrosis via inhibition of transforming growth factor-beta 1/suppressor of mothers against decapentaplegic (TGF-ß1/Smad) pathway and alpha-smooth muscle actin (α-SMA). Therefore, these results suggest that EA might be a potential prophylactic agent for the treatment of alcoholic liver disease.


Asunto(s)
Hígado Graso Alcohólico , Hígado Graso , Ratones , Animales , Quempferoles/farmacología , Hígado/metabolismo , Ratones Endogámicos C57BL , Hígado Graso Alcohólico/metabolismo , Etanol/toxicidad , Etanol/metabolismo , Hígado Graso/metabolismo , Inflamación/metabolismo , Colesterol/metabolismo , Glucósidos/farmacología , Biomarcadores/metabolismo , Estrés Oxidativo
5.
World J Microbiol Biotechnol ; 40(9): 261, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38972914

RESUMEN

The fecal microbiota of two healthy adults was cultivated in a medium containing commercial fructooligosaccharides [FOS; 1-kestose (GF2), nystose (GF3), and 1F-fructofuranosylnystose (GF4)]. Initially, the proportions of lactobacilli in the two feces samples were only 0.42% and 0.17%; however, they significantly increased to 7.2% and 4.8%, respectively, after cultivation on FOS. Most FOS-utilizing isolates could utilize only GF2; however, Lacticaseibacillus paracasei strain Lp02 could fully consume GF3 and GF4 too. The FOS operon (fosRABCDXE) was present in Lc. paracasei Lp02 and another Lc. paracasei strain, KCTC 3510T, but fosE was only partially present in the non-FOS-degrading strain KCTC 3510T. In addition, the top six upregulated genes in the presence of FOS were fosABCDXE, particularly fosE. FosE is a ß-fructosidase that hydrolyzes both sucrose and all three FOS. Finally, a genome-based analysis suggested that fosE is mainly observed in Lc. paracasei, and only 13.5% (61/452) of their reported genomes were confirmed to include it. In conclusion, FosE allows the utilization of FOS, including GF3 and GF4 as well as GF2, by some Lc. paracasei strains, suggesting that this species plays a pivotal role in FOS utilization in the human gut.


Asunto(s)
Heces , Microbioma Gastrointestinal , Lacticaseibacillus paracasei , Oligosacáridos , beta-Fructofuranosidasa , Humanos , Oligosacáridos/metabolismo , Heces/microbiología , Lacticaseibacillus paracasei/metabolismo , Lacticaseibacillus paracasei/genética , beta-Fructofuranosidasa/metabolismo , beta-Fructofuranosidasa/genética , Adulto , Operón , Trisacáridos/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
6.
Acta Neurochir (Wien) ; 165(8): 2105-2109, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37421424

RESUMEN

Gamma knife radiosurgery (GKRS) has been accepted as a safe and effective treatment for vestibular schwannoma (VS). However, during follow-up, tumor expansion induced by irradiation can occur, and diagnosis of failure in radiosurgery for VS is still controversial. Tumor expansion with cystic enlargement causes some confusion regarding whether further treatment should be performed. We analyzed more than 10 years of clinical findings and imaging of patients with VS with cystic enlargement after GKRS. A 49-year-old male with hearing impairment was treated with GKRS (12 Gy; isodose, 50%) for a left VS with a preoperative tumor volume of 0.8 cc. The tumor size increased with cystic changes from the third year after GKRS, reaching a volume of 10.8 cc at 5 years after GKRS. At the 6th year of follow-up, the tumor volume started to decrease, up to 0.3 cc by the 14th year of follow-up. A 52-year-old female with hearing impairment and left facial numbness was treated with GKRS for a left VS (13 Gy; isodose, 50%). The preoperative tumor volume was 6.3 cc, which started to increase with cystic enlargement from the first year after GKRS, and reaching 18.2 cc by 5 years after GKRS. The tumor maintained a cystic pattern with slight changes in size, but no other neurologic symptoms developed during the follow-up period. After 6 years of GKRS, tumor regression was observed, eventually reaching a volume of 3.2 cc by the 13th year of follow-up. In both cases, persistent cystic enlargement in VS was observed at 5 years after GKRS, after which the tumors began to stabilize. After more than 10 years of GKRS, the tumor volume was less than that before GKRS. Enlargement with large cystic formation in the first 3-5 years after GKRS has been considered as treatment failure. However, our cases show that further treatment for cystic enlargement should be deferred for at least 10 years, especially in patients without neurological deterioration, as inadequate surgery can be prevented within that period.


Asunto(s)
Pérdida Auditiva , Neuroma Acústico , Radiocirugia , Masculino , Femenino , Humanos , Persona de Mediana Edad , Neuroma Acústico/diagnóstico por imagen , Neuroma Acústico/radioterapia , Neuroma Acústico/cirugía , Radiocirugia/efectos adversos , Radiocirugia/métodos , Resultado del Tratamiento , Insuficiencia del Tratamiento , Pérdida Auditiva/etiología , Estudios Retrospectivos , Estudios de Seguimiento
7.
BMC Med Inform Decis Mak ; 23(1): 190, 2023 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-37735681

RESUMEN

BACKGROUND: One of the most common sleep disorders is sleep apnea syndrome. To diagnose sleep apnea syndrome, polysomnography is typically used, but it has limitations in terms of labor, cost, and time. Therefore, studies have been conducted to develop automated detection algorithms using limited biological signals that can be more easily diagnosed. However, the lack of information from limited signals can result in uncertainty from artificial intelligence judgments. Therefore, we performed selective prediction by using estimated respiratory signals from electrocardiogram and oxygen saturation signals based on confidence scores to classify only those sleep apnea occurrence samples with high confidence. In addition, for samples with high uncertainty, this algorithm rejected them, providing a second opinion to the clinician. METHOD: Our developed model utilized polysomnography data from 994 subjects obtained from Massachusetts General Hospital. We performed feature extraction from the latent vector using the autoencoder. Then, one dimensional convolutional neural network-long short-term memory (1D CNN-LSTM) was designed and trained to measure confidence scores for input, with an additional selection function. We set a confidence score threshold called the target coverage and performed optimization only on samples with confidence scores higher than the target coverage. As a result, we demonstrated that the empirical coverage trained in the model converged to the target coverage. RESULT: To confirm whether the model has been optimized according to the objectives, the coverage violation was used to measure the difference between the target coverage and the empirical coverage. As a result, the value of coverage violation was found to be an average of 0.067. Based on the model, we evaluated the classification performance of sleep apnea and confirmed that it achieved 90.26% accuracy, 91.29% sensitivity, and 89.21% specificity. This represents an improvement of approximately 7.03% in all metrics compared to the performance achieved without using a selective prediction. CONCLUSION: This algorithm based on selective prediction utilizes confidence measurement method to minimize the problem caused by limited biological information. Based on this approach, this algorithm is applicable to wearable devices despite low signal quality and can be used as a simple detection method that determine the need for polysomnography or complement it.


Asunto(s)
Inteligencia Artificial , Síndromes de la Apnea del Sueño , Humanos , Algoritmos , Benchmarking , Electrocardiografía , Síndromes de la Apnea del Sueño/diagnóstico
8.
Medicina (Kaunas) ; 58(3)2022 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-35334529

RESUMEN

Background and Objectives: This study analyzed the prognostic impact of mechanical cardiopulmonary resuscitation (CPR) devices in out-of-hospital cardiac arrest (OHCA) patients, in comparison to manual CPR. Materials and Methods: This study was a nationwide population-based observational study in South Korea. Data were retrospectively collected from 142,905 OHCA patients using the South Korean Out-of-Hospital Cardiac Arrest Surveillance database. We included adult OHCA patients who received manual or mechanical CPR in the emergency room. The primary outcome was survival at discharge and the secondary outcome was sustained return of spontaneous circulation (ROSC). Statistical analysis included propensity score matching and multivariate logistic regression. Results: A total of 19,045 manual CPR and 1125 mechanical CPR cases (671 AutoPulseTM vs. 305 ThumperTM vs. 149 LUCASTM) were included. In the matched multivariate analyses, all mechanical CPR devices were associated with a lower ROSC than that of manual CPR. AutoPulseTM was associated with lower survival in the multivariate analysis after matching (aOR with 95% CI: 0.57 (0.33-0.96)), but the other mechanical CPR devices were associated with similar survival to discharge as that of manual CPR. Witnessed arrest was commonly associated with high ROSC, but the use of mechanical CPR devices and cardiac origin arrest were associated with low ROSC. Only target temperature management was the common predictor for high survival. Conclusions: The mechanical CPR devices largely led to similar survival to discharge as that of manual CPR in OHCA patients; however, the in-hospital use of the AutoPulseTM device for mechanical CPR may significantly lower survival compared to manual CPR.


Asunto(s)
Reanimación Cardiopulmonar , Paro Cardíaco Extrahospitalario , Adulto , Hospitales , Humanos , Paro Cardíaco Extrahospitalario/terapia , Pronóstico , Estudios Retrospectivos
9.
Eur J Cancer Care (Engl) ; 30(2): e13371, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33184971

RESUMEN

OBJECTIVE: To investigate the influence of type-D personality on quality of life (QoL) in patients with primary brain tumours. METHODS: We performed descriptive cross-sectional study between July 2018 and March 2019. A convenience sample of 293 patients was recruited from an outpatient neurosurgery clinic. RESULTS: Type-D personality was identified in 34.1% of subjects. Type-D patients had poorer QoL and experienced more severe symptoms and interference with life. Poor QoL was associated with lower education, no spouse and lower family income. Symptoms were the most significant factor affecting QoL, followed by type-D personality, income and education. CONCLUSION: Symptoms, type-D personality and demographic factors should be considered when assessing QoL in patients with primary brain tumours. Interventions that reflect these characteristics, including type-D personality, may help improve QoL for patients with primary brain tumours.


Asunto(s)
Neoplasias Encefálicas , Personalidad Tipo D , Estudios Transversales , Humanos , Pacientes Ambulatorios , Personalidad , Calidad de Vida , Encuestas y Cuestionarios
10.
Sensors (Basel) ; 21(21)2021 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-34770273

RESUMEN

The development and use of wearable devices require high levels of security and have sparked interest in biometric authentication research. Among the available approaches, electrocardiogram (ECG) technology is attracting attention because of its strengths in spoofing. However, morphological changes of ECG, which are affected by physical and psychological factors, can make authentication difficult. In this paper, we propose authentication using non-linear normalization of ECG beats that is robust to changes in ECG waveforms according to heart rate fluctuations in various daily activities. We performed a non-linear normalization method through the analysis of ECG alongside heart rate, evaluating similarities and authenticating the performance of our new method compared to existing methods. Compared with beats before normalization, the average similarity of the proposed method increased 23.7% in the resting state and 43% in the non-resting state. After learning in the resting state, authentication performance reached 99.05% accuracy for the resting state and 88.14% for the non-resting state. The proposed method can be applicable to an ECG-based authentication system under various physiological conditions.


Asunto(s)
Identificación Biométrica , Dispositivos Electrónicos Vestibles , Electrocardiografía , Frecuencia Cardíaca , Aprendizaje
11.
Int J Mol Sci ; 22(11)2021 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-34199599

RESUMEN

Orphan nuclear receptor estrogen-related receptor γ (ERRγ) is an important transcription factor modulating gene transcription involved in endocrine control of liver metabolism. Transferrin receptor 2 (TFR2), a carrier protein for transferrin, is involved in hepatic iron overload in alcoholic liver disease (ALD). However, TFR2 gene transcriptional regulation in hepatocytes remains largely unknown. In this study, we described a detailed molecular mechanism of hepatic TFR2 gene expression involving ERRγ in response to an endocannabinoid 2-arachidonoylglycerol (2-AG). Treatment with 2-AG and arachidonyl-2'-chloroethylamide, a selective cannabinoid receptor type 1 (CB1) receptor agonist, increased ERRγ and TFR2 expression in hepatocytes. Overexpression of ERRγ was sufficient to induce TFR2 expression in both human and mouse hepatocytes. In addition, ERRγ knockdown significantly decreased 2-AG or alcohol-mediated TFR2 gene expression in cultured hepatocytes and mouse livers. Finally, deletion and mutation analysis of the TFR2 gene promoter demonstrated that ERRγ directly modulated TFR2 gene transcription via binding to an ERR-response element. This was further confirmed by chromatin immunoprecipitation assay. Taken together, these results reveal a previously unrecognized role of ERRγ in the transcriptional regulation of TFR2 gene expression in response to alcohol.


Asunto(s)
Hepatopatías Alcohólicas/genética , Hígado/efectos de los fármacos , Receptor Cannabinoide CB1/genética , Receptores de Estrógenos/genética , Receptores de Transferrina/genética , Alcoholes/farmacología , Animales , Ácidos Araquidónicos/farmacología , Endocannabinoides/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Glicéridos/farmacología , Células Hep G2 , Hepatocitos/efectos de los fármacos , Humanos , Hierro/metabolismo , Hígado/metabolismo , Hígado/patología , Hepatopatías Alcohólicas/metabolismo , Hepatopatías Alcohólicas/patología , Ratones , Regiones Promotoras Genéticas , Receptor Cannabinoide CB1/agonistas , Eliminación de Secuencia/genética , Transferrina/genética , Transferrina/metabolismo
12.
Medicina (Kaunas) ; 57(7)2021 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-34203291

RESUMEN

Background and Objectives: Abnormal epileptic discharges in the brain can affect the central brain regions that regulate autonomic activity and produce cardiac symptoms, either at onset or during propagation of a seizure. These autonomic alterations are related to cardiorespiratory disturbances, such as sudden unexpected death in epilepsy. This study aims to investigate the differences in cardiac autonomic function between patients with temporal lobe epilepsy (TLE) and frontal lobe epilepsy (FLE) using ultra-short-term heart rate variability (HRV) analysis around seizures. Materials and Methods: We analyzed electrocardiogram (ECG) data recorded during 309 seizures in 58 patients with epilepsy. Twelve patients with FLE and 46 patients with TLE were included in this study. We extracted the HRV parameters from the ECG signal before, during and after the ictal interval with ultra-short-term HRV analysis. We statistically compared the HRV parameters using an independent t-test in each interval to compare the differences between groups, and repeated measures analysis of variance was used to test the group differences in longitudinal changes in the HRV parameters. We performed the Tukey-Kramer multiple comparisons procedure as the post hoc test. Results: Among the HRV parameters, the mean interval between heartbeats (RRi), normalized low-frequency band power (LF) and LF/HF ratio were statistically different between the interval and epilepsy types in the t-test. Repeated measures ANOVA showed that the mean RRi and RMSSD were significantly different by epilepsy type, and the normalized LF and LF/HF ratio significantly interacted with the epilepsy type and interval. Conclusions: During the pre-ictal interval, TLE patients showed an elevation in sympathetic activity, while the FLE patients showed an apparent increase and decrease in sympathetic activity when entering and ending the ictal period, respectively. The TLE patients showed a maintained elevation of sympathetic and vagal activity in the pos-ictal interval. These differences in autonomic cardiac characteristics between FLE and TLE might be relevant to the ictal symptoms which eventually result in SUDEP.


Asunto(s)
Epilepsia del Lóbulo Frontal , Epilepsia del Lóbulo Temporal , Sistema Nervioso Autónomo , Electroencefalografía , Epilepsia del Lóbulo Temporal/complicaciones , Frecuencia Cardíaca , Humanos , Convulsiones
13.
Anal Chem ; 92(1): 774-781, 2020 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-31789495

RESUMEN

Although N-shaped fast scan cyclic voltammetry (N-FSCV) is well-established as an electroanalytical method to measure extracellular serotonin concentrations in vivo, it is in need of improvement in both sensitivity and selectivity. Based on our previous studies using fast cyclic square-wave voltammetry (FCSWV) for in vivo dopamine measurements, we have modified this technique to optimize the detection of serotonin in vivo. A series of large amplitude square-shaped potentials was superimposed onto an N-shaped waveform to provide cycling through multiple redox reactions within the N-shaped waveform to enhance the sensitivity and selectivity to serotonin measurement when combined with a two-dimensional voltammogram. N-Shaped fast cyclic square-wave voltammetry (N-FCSWV) showed significantly higher sensitivity to serotonin compared to conventional N-FSCV. In addition, N-FCSWV showed better performance than conventional N-shaped FSCV in differentiating serotonin from its major interferents, dopamine and 5-hydroxyindoleascetic acid (5-HIAA). It was also confirmed that the large amplitude of the square waveform did not influence local neuronal activity, and it could monitor electrical stimulation evoked phasic release of serotonin in the rat substantia nigra pars reticulata (SNr) before and after systemic injection of escitalopram (ESCIT, 10 mg/kg i.p.), a serotonin selective reuptake inhibitor.


Asunto(s)
Técnicas Electroquímicas/instrumentación , Serotonina/análisis , Animales , Química Encefálica , Técnicas Electroquímicas/métodos , Diseño de Equipo , Masculino , Microelectrodos , Ratas Sprague-Dawley
14.
Small ; 16(12): e1903572, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31782908

RESUMEN

Carbon nitrides with a high N/C atomic ratio (>2) are expected to offer superior basicity and unique electronic properties. However, the synthesis of these nanostructures is highly challenging since many parts of the CN frameworks in the carbon nitride should be replaced with thermodynamically less stable NN frameworks as the nitrogen content increases. Thermodynamically stable C3 N7 and C3 N6 with an ordered mesoporous structure are synthesized at 250 and 300 °C respectively via a pyrolysis process of 5-amino-1H-tetrazole (5-ATTZ). Polymerization of the precursor to the ordered mesoporous C3 N7 and C3 N6 is clearly proved by X-ray and electron diffraction analyses. A combined analysis including diverse spectroscopy and FDMNES and density functional theory (DFT) calculations demonstrates that the NN bonds are stabilized in the form of tetrazine and/or triazole moieties in the C3 N7 and C3 N6 . The ordered mesoporous C3 N7 represents the better oxygen reduction reaction (ORR) performances (onset potential: 0.81 V vs reversible hydrogen electrode (RHE), electron transfer number: 3.9 at 0.5 V vs RHE) than graphitic carbon nitride (g-C3 N4 ) and the ordered mesoporous C3 N6 . The study on the mechanism of ORR suggests that nitrogen atoms in the tetrazine moiety of the ordered mesoporous C3 N7 act as active sites for its improved ORR activity.

15.
Part Fibre Toxicol ; 17(1): 34, 2020 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-32680532

RESUMEN

BACKGROUND: Nanotechnology is indispensable to many different applications. Although nanoparticles have been widely used in, for example, cosmetics, sunscreen, food packaging, and medications, they may pose human safety risks associated with nanotoxicity. Thus, toxicity testing of nanoparticles is essential to assess the relative health risks associated with consumer exposure. METHODS: In this study, we identified the NOAEL (no observed adverse effect level) of the agglomerated/aggregated TiO2 P25 (approximately 180 nm) administered at repeated doses to Sprague-Dawley (SD) rats for 28 and 90 days. Ten of the 15 animals were necropsied for toxicity evaluation after the repeated-dose 90-day study, and the remaining five animals were allowed to recover for 28 days. The agglomerated/aggregated TiO2 P25 dose levels used included 250 mg kg- 1 d- 1 (low), 500 mg kg- 1 d- 1 (medium), and 1000 mg kg- 1 d- 1 (high), and their effects were compared with those of the vehicle control. During the treatment period, the animals were observed for mortality, clinical signs (detailed daily and weekly clinical observations), functional observation battery, weekly body weight, and food and water consumption and were also subjected to ophthalmological examination and urinalysis. After termination of the repeated-dose 28-day, 90-day, and recovery studies, clinical pathology (hematology, blood coagulation time, and serum biochemistry), necropsy (organ weights and gross findings), and histopathological examinations were performed. RESULTS: No systemic toxicological effects were associated with the agglomerated/aggregated TiO2 P25 during the repeated-dose 28-day, 90-day, and recovery studies in SD rats. Therefore, the NOAEL of the agglomerated/aggregated TiO2 P25 was identified as 1000 mg kg- 1 d- 1, and the substance was not detected in the target organs. CONCLUSION: Subacute and subchronic oral administration of the agglomerated/aggregated TiO2 P25 was unlikely to cause side effects or toxic reactions in rats.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Material Particulado/toxicidad , Titanio/toxicidad , Administración Oral , Animales , Relación Dosis-Respuesta a Droga , Nanopartículas , Nanotecnología , Ratas , Ratas Sprague-Dawley , Pruebas de Toxicidad
16.
Addict Biol ; 25(4): e12805, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31297935

RESUMEN

Heart rate variability (HRV) can be used to represent the regulatory adaptive system and is a proxy for neurovisceral integration. Consistent with the view that, like other addictions, Internet gaming disorder (IGD) involves disrupted regulatory function, the present study hypothesized that IGD patients would show (a) decreased HRV, (b) ineffective functional neural connectivity, and (c) differential patterns of association between HRV and functional neural connectivity relative to healthy controls (HCs). The present study included 111 young adults (53 IGD patients and 58 age- and sex-matched HCs) who underwent simultaneous recordings with an electrocardiogram and electroencephalogram during a resting state. Heart rate (HR), HRV, and functional neural connectivity were calculated using the graph theory approach. Compared with the HCs, the IGD patients exhibited elevated HR and decreased HRV based on the high frequency (HF), which reflects suppression of parasympathetic and/or vagal tone. The IGD patients also exhibited a heightened theta band characteristic path length (CPL) compared with HCs, indicating decreased efficacy of the functional network. Furthermore, IGD patients exhibited negative correlations between the standard deviation of the normal-to-normal interval index (SDNNi) and theta and delta CPL values, which were not observed in HCs. In conclusion, the present findings suggest that IGD patients might have maladaptive brain-body integration features involving disruptions of the autonomic nervous system and brain function.


Asunto(s)
Encéfalo/fisiopatología , Frecuencia Cardíaca/fisiología , Trastorno de Adicción a Internet/fisiopatología , Sistema Nervioso Parasimpático/fisiopatología , Adulto , Estudios de Casos y Controles , Electrocardiografía , Electroencefalografía , Femenino , Humanos , Masculino , Vías Nerviosas/fisiología , Ritmo Teta/fisiología , Adulto Joven
17.
Sensors (Basel) ; 20(5)2020 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-32182772

RESUMEN

Photoplethysmography (PPG) is an easy and convenient method by which to measure heart rate (HR). However, PPG signals that optically measure volumetric changes in blood are not robust to motion artifacts. In this paper, we develop a PPG measuring system based on multi-channel sensors with multiple wavelengths and propose a motion artifact reduction algorithm using independent component analysis (ICA). We also propose a truncated singular value decomposition for 12-channel PPG signals, which contain direction and depth information measured using the developed multi-channel PPG measurement system. The performance of the proposed method is evaluated against the R-peaks of an electrocardiogram in terms of sensitivity (Se), positive predictive value (PPV), and failed detection rate (FDR). The experimental results show that Se, PPV, and FDR were 99%, 99.55%, and 0.45% for walking, 96.28%, 99.24%, and 0.77% for fast walking, and 82.49%, 99.83%, and 0.17% for running, respectively. The evaluation shows that the proposed method is effective in reducing errors in HR estimation from PPG signals with motion artifacts in intensive motion situations such as fast walking and running.


Asunto(s)
Artefactos , Fotopletismografía/instrumentación , Procesamiento de Señales Asistido por Computador/instrumentación , Dispositivos Electrónicos Vestibles , Adulto , Electrocardiografía , Diseño de Equipo , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Caminata/fisiología , Adulto Joven
18.
Sensors (Basel) ; 20(21)2020 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-33167512

RESUMEN

Hand functions affect the instrumental activities of daily living. While functional outcome measures, such as a targeted box and block test, have been widely used in clinical settings and provide a useful measure of overall performance, the advent of a wearable Inertial Measurement Unit(IMU)-based system enables the examination of the specific performance and kinematic parameters of hand movements. This study proposed a novel clip-on IMU system to facilitate the clinically fitted measurements of fine-motor finger and wrist joint movements. Clinical validation was conducted with the aim of characterising age-related changes in hand functions, namely grasping, transporting, and releasing blocks. Eighteen young (age 20-31) and sixteen healthy older adults (age 75-89) were evaluated during the box and block test. The results demonstrated that an older age was characterized by slower movements and higher variations and kinematic alterations in the hand functions, such as a larger range of motions at the fingers as well as kinematic trajectories. The proposed IMU system and subsequent validations highlight the value of the performance and kinematics parameters for a more comprehensive understanding of fine-motor finger and wrist movements that could shed light on further implementations in clinical and practical settings.


Asunto(s)
Actividades Cotidianas , Mano , Movimiento , Dispositivos Electrónicos Vestibles , Adulto , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Dedos , Humanos , Muñeca , Adulto Joven
19.
Medicina (Kaunas) ; 56(10)2020 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-32987834

RESUMEN

Background and objectives: Hyperuricemia is one of the well-known cardiovascular risk factors. There is a growing interest in the association between hyperuricemia and arrhythmia. We used the representative sample data of Korean population to study the association between hyperuricemia and heart rate irregularity (HRI) that reflects total arrhythmia. Materials and Methods: We performed weighted multivariate logistic regression analysis to assess the association between hyperuricemia and HRI. Results: Of the 10,827 subjects, 1308 (13.2%) had hyperuricemia and 130 (1%) had HRI. In the presence of hyperuricemia, HRI was three times higher than that in the absence of hyperuricemia (OR 2.98, 95% CI 1.71-5.18). The risk of HRI was highest in subjects with both hypertension and hyperuricemia. In the subgroup analysis, the association of hyperuricemia with HRI was most pronounced in the smoker group. Conclusions: Hyperuricemia was highly correlated with HRI in adult Korean representative sample data. Hyperuricemia was associated with a nearly tripled risk for HRI. Hypertension has a synergistic effect with hyperuricemia on HRI. Further research is warranted to clarify the relationship between hyperuricemia and arrhythmia and its mechanism.


Asunto(s)
Hiperuricemia , Adulto , Estudios Transversales , Frecuencia Cardíaca , Humanos , Hiperuricemia/complicaciones , Hiperuricemia/epidemiología , Encuestas Nutricionales , República de Corea/epidemiología , Factores de Riesgo , Ácido Úrico
20.
Hum Brain Mapp ; 40(8): 2336-2346, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30648326

RESUMEN

A number of previous studies revealed the importance of the frontoparietal network for attention and preparatory top-down control. Here, we investigated the theta (7-9 Hz) coherence of the right frontoparietal networks to explore the differences in connectivity changes for the right frontoparietal regions during spatial attention (i.e., attention to a specific location rather than a specific feature) and nonspatial attention (i.e., attention to a specific feature rather than a specific location) tasks. The theta coherence in both tasks was primarily maintained at a preparatory state, decreases after stimulus onset, and recovers to the level of the preparatory state after the response time. However, the theta coherence of the frontoparietal network during spatial attention was immediately maintained after cue-onset, whereas for the case of nonspatial attention, it was immediately decreased after cue-onset. In addition, the connectivity of the right frontoparietal network, including the middle frontal gyrus and superior parietal lobe, were significantly higher for spatial attention rather than for nonspatial attention, suggesting that the dorsal parts of right frontoparietal network are more engaged in spatial-specific attention from the preparatory state. These findings also suggest that these two attention systems involve the use of different regional connectivity patterns, not only in the cognitive state, but in the preparatory state as well.


Asunto(s)
Atención/fisiología , Electrocorticografía , Lóbulo Frontal/fisiología , Red Nerviosa/fisiología , Lóbulo Parietal/fisiología , Percepción Espacial/fisiología , Ritmo Teta/fisiología , Percepción Visual/fisiología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
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