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1.
Invest New Drugs ; 42(1): 80-88, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38099989

RESUMEN

AIM: Venadaparib is a next-generation poly(ADP-ribose) polymerase inhibitor under development for treating gastric cancer. This study aimed to evaluate the effects of food and ethnicity on the pharmacokinetics (PKs) and safety of venadaparib after a single oral administration in healthy Korean, Caucasian, and Chinese male subjects. METHODS: In this randomized, open-label, single-dose, two-sequence, two-period, and crossover study, Korean and Caucasian subjects received venadaparib 80 mg in each period (fasted or fed state) with a seven-day washout. In an open-label, single-dose study, Chinese subjects received venadaparib 80 mg only in the fasted state. Serial blood samples were collected up to 72 h post-dosing. RESULTS: Twelve subjects from each ethnic group completed the study. The geometric mean ratios (90% confidence intervals) of the maximum plasma concentration (Cmax) and area under the plasma concentration-time curve from time zero to the last measurable time point (AUClast) of venadaparib for the fed to fasted state were 0.82 (0.7457-0.9094) and 1.02 (0.9088-1.1339) in Koreans, and 0.77 (0.6871-0.8609) and 0.96 (0.9017-1.0186) in Caucasians, respectively. No statistically significant differences were observed in Cmax (P-value = 0.45) or AUClast (P-value = 0.30) among the three ethnic groups. A single venadaparib dose was well-tolerated. CONCLUSION: The overall systemic exposure of venadaparib was not affected by the high-fat meal, despite delayed absorption with a decreased Cmax in the fed state. The PK profiles were comparable among the Korean, Caucasian, and Chinese subjects. A single venadaparib 80 mg dose was safe and well-tolerated in both fasted and fed states.


Asunto(s)
Etnicidad , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Humanos , Masculino , Inhibidores de Poli(ADP-Ribosa) Polimerasas/efectos adversos , Estudios Cruzados , Área Bajo la Curva , Interacciones Alimento-Droga , Voluntarios Sanos , Administración Oral , República de Corea , China
2.
BMC Pregnancy Childbirth ; 24(1): 115, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38326770

RESUMEN

BACKGROUND: Non-communicating rudimentary horn pregnancy (NCRHP) lead to life-threatening condition for both mother and fetus. Early diagnosis of NCRHP and laparoscopic resection is important to prevent catastrophic conditions. However, delayed diagnosis until the second or third trimester makes it difficult to accurately diagnose between NCRHP and bicornuate uterine pregnancy, as both conditions present uterine rupture and massive hemoperitoneum. Furthermore, these rare cases are challenging in pregnancy trials and associated with adverse outcomes in subsequent pregnancies. CASE PRESENTATION: A 31-year-old gravida 1 para 0 Korean woman visited our infertility center with a confirmed positive urine pregnancy test after timed intercourse. Before she was scheduled to have timed intercourse, a unicornuate uterus with a non-communicating right uterine horn was suspected based on an ultrasound scan and hysterosalpingography during the initial infertility workup. A gestational sac was observed in the right non-communicating rudimentary horn at 5 weeks of gestation. Serum beta-human chorionic gonadotropin (b-hCG) level was 2052.0mIU/mL. An elective laparoscopic resection of the right rudimentary horn containing a gestational sac, along with ipsilateral salpingectomy, was performed with no adverse event. After 3-month of recovery period and three cycles of conceptional trials involving timed intercourse and intrauterine insemination, in-vitro fertilization (IVF) was performed using the antagonist protocol, and successful pregnancy was confirmed. The patient had been hospitalized from 21 + 6 weeks to 35 + 6 weeks of gestation, underwent cerclage placement and tocolytics with corticosteroid treatment. She delivered an early-term male baby by cesarean section. CONCLUSION: In this rare case, the successful pregnancy achieved through IVF following the appropriate management of NCRHP under laparoscopy underscores the critical importance of early diagnosis and intervention in cases of NCRHP. Timely identification and management of NCRHP are vital to prevent the occurrence of catastrophic conditions and to enhance the prognosis of a successful pregnancy through assisted reproductive technology (ART). Therefore, a high index of suspicion for NCRHP is important and employs a range of diagnostic modalities.


Asunto(s)
Infertilidad , Laparoscopía , Embarazo Cornual , Adulto , Femenino , Humanos , Masculino , Embarazo , Cesárea , Fertilización , Fertilización In Vitro , Resultado del Embarazo , Embarazo Cornual/cirugía , Útero/cirugía , Recién Nacido
3.
Neurocrit Care ; 40(2): 538-550, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37353670

RESUMEN

BACKGROUND: Early identification of the severity of hypoxic-ischemic brain injury (HIBI) after cardiac arrest can be used to help plan appropriate subsequent therapy. We evaluated whether conductivity of cerebral tissue measured using magnetic resonance-based conductivity imaging (MRCI), which provides contrast derived from the concentration and mobility of ions within the imaged tissue, can reflect the severity of HIBI in the early hours after cardiac arrest. METHODS: Fourteen minipigs were resuscitated after 5 min or 12 min of untreated cardiac arrest. MRCI was performed at baseline and at 1 h and 3.5 h after return of spontaneous circulation (ROSC). RESULTS: In both groups, the conductivity of cerebral tissue significantly increased at 1 h after ROSC compared with that at baseline (P = 0.031 and 0.016 in the 5-min and 12-min groups, respectively). The increase was greater in the 12-min group, resulting in significantly higher conductivity values in the 12-min group (P = 0.030). At 3.5 h after ROSC, the conductivity of cerebral tissue in the 12-min group remained increased (P = 0.022), whereas that in the 5-min group returned to its baseline level. CONCLUSIONS: The conductivity of cerebral tissue was increased in the first hours after ROSC, and the increase was more prominent and lasted longer in the 12-min group than in the 5-min group. Our findings suggest the promising potential of MRCI as a tool to estimate the severity of HIBI in the early hours after cardiac arrest.


Asunto(s)
Lesiones Encefálicas , Reanimación Cardiopulmonar , Paro Cardíaco , Humanos , Animales , Porcinos , Estudios de Factibilidad , Porcinos Enanos , Paro Cardíaco/diagnóstico por imagen , Paro Cardíaco/terapia , Espectroscopía de Resonancia Magnética , Reanimación Cardiopulmonar/métodos
4.
J Neuroeng Rehabil ; 21(1): 58, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38627779

RESUMEN

BACKGROUND: Identification of cortical loci for lower limb movements for stroke rehabilitation is crucial for better rehabilitation outcomes via noninvasive brain stimulation by targeting the fine-grained cortical loci of the movements. However, identification of the cortical loci for lower limb movements using functional MRI (fMRI) is challenging due to head motion and difficulty in isolating different types of movement. Therefore, we developed a custom-made MR-compatible footplate and leg cushion to identify the cortical loci for lower limb movements and conducted multivariate analysis on the fMRI data. We evaluated the validity of the identified loci using both fMRI and behavioral data, obtained from healthy participants as well as individuals after stroke. METHODS: We recruited 33 healthy participants who performed four different lower limb movements (ankle dorsiflexion, ankle rotation, knee extension, and toe flexion) using our custom-built equipment while fMRI data were acquired. A subgroup of these participants (Dataset 1; n = 21) was used to identify the cortical loci associated with each lower limb movement in the paracentral lobule (PCL) using multivoxel pattern analysis and representational similarity analysis. The identified cortical loci were then evaluated using the remaining healthy participants (Dataset 2; n = 11), for whom the laterality index (LI) was calculated for each lower limb movement using the cortical loci identified for the left and right lower limbs. In addition, we acquired a dataset from 15 individuals with chronic stroke for regression analysis using the LI and the Fugl-Meyer Assessment (FMA) scale. RESULTS: The cortical loci associated with the lower limb movements were hierarchically organized in the medial wall of the PCL following the cortical homunculus. The LI was clearer using the identified cortical loci than using the PCL. The healthy participants (mean ± standard deviation: 0.12 ± 0.30; range: - 0.63 to 0.91) exhibited a higher contralateral LI than the individuals after stroke (0.07 ± 0.47; - 0.83 to 0.97). The corresponding LI scores for individuals after stroke showed a significant positive correlation with the FMA scale for paretic side movement in ankle dorsiflexion (R2 = 0.33, p = 0.025) and toe flexion (R2 = 0.37, p = 0.016). CONCLUSIONS: The cortical loci associated with lower limb movements in the PCL identified in healthy participants were validated using independent groups of healthy participants and individuals after stroke. Our findings suggest that these cortical loci may be beneficial for the neurorehabilitation of lower limb movement in individuals after stroke, such as in developing effective rehabilitation interventions guided by the LI scores obtained for neuronal activations calculated from the identified cortical loci across the paretic and non-paretic sides of the brain.


Asunto(s)
Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Movimiento/fisiología , Extremidad Inferior , Imagen por Resonancia Magnética
5.
Int J Mol Sci ; 25(3)2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38338992

RESUMEN

Knee osteoarthritis (OA), an age-related degenerative disease characterized by severe pain and disability, is treated using polynucleotides (PNs) and hyaluronic acid (HA). The intra-articular (IA) injection of HA has been studied extensively in both animal models and in humans; however, the efficacy and mechanisms of action remain unclear. In addition, there has been a paucity of research regarding the use of PN alone or in combination with HA in OA. To investigate the effect of the combined injection of PN and HA in vivo, pathological and behavioral changes were assessed in an OA model. Anterior cruciate ligament transection and medial meniscectomy were performed in Sprague-Dawley rats to create the OA animal model. The locomotor activity improved following PNHA injection, while the OARSI grade improved in the medial tibia and femur. In mild OA, TNFα levels decreased histologically in the PN, HA, and PNHA groups but only the PNHA group showed behavioral improvement in terms of distance. In conclusion, PNHA exhibited anti-inflammatory effects during OA progression and improved locomotor activity regardless of the OARSI grade.


Asunto(s)
Ácido Hialurónico , Osteoartritis de la Rodilla , Ratas , Humanos , Animales , Ácido Hialurónico/farmacología , Polinucleótidos/farmacología , Polinucleótidos/uso terapéutico , Ratas Sprague-Dawley , Osteoartritis de la Rodilla/tratamiento farmacológico , Ligamento Cruzado Anterior/cirugía , Inyecciones Intraarticulares
6.
Environ Res ; 233: 116411, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37354929

RESUMEN

The growing use of plastic materials has resulted in a constant increase in the risk associated with microplastics (MPs). Ultra-violet (UV) light and wind break down modify MPs in the environment into smaller particles known as weathered MPs (WMPs) and these processes increase the risk of MP toxicity. The neurotoxicity of weathered polystyrene-MPs remains unclear. Therefore, it is important to understand the risks posed by WMPs. We evaluated the chemical changes of WMPs generated under laboratory-synchronized environmentally mimetic conditions and compared them with virgin MPs (VMPs). We found that WMP had a rough surface, slight yellow color, reduced molecular weight, and structural alteration compared with those of VMP. Next, 2 µg of ∼100 µm in size of WMP and VMP were orally administered once a day for one week to C57BL/6 male mice. Proteomic analysis revealed that the WMP group had significantly increased activation of immune and neurodegeneration-related pathways compared with that of the VMP group. Consistently, in in vitro experiments, the human brain-derived microglial cell line (HMC-3) also exhibited a more severe inflammatory response to WMP than to VMP. These results show that WMP is a more profound inflammatory factor than VMP. In summary, our findings demonstrate the toxicity of WMPs and provide theoretical insights into their potential risks to biological systems and even humans in the ecosystem.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Animales , Humanos , Ratones , Masculino , Microplásticos/toxicidad , Plásticos , Poliestirenos/toxicidad , Poliestirenos/análisis , Proteoma , Ecosistema , Proteómica , Ratones Endogámicos C57BL , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , Encéfalo
7.
Sensors (Basel) ; 22(19)2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-36236775

RESUMEN

Crowdfunding has seen an enormous rise, becoming a new alternative funding source for emerging companies or new startups in recent years. As crowdfunding prevails, it is also under substantial risk of the occurrence of fraud. Though a growing number of articles indicate that crowdfunding scams are a new imminent threat to investors, little is known about them primarily due to the lack of measurement data collected from real scam cases. This paper fills the gap by collecting, labeling, and analyzing publicly available data of a hundred fraudulent campaigns on a crowdfunding platform. In order to find and understand distinguishing characteristics of crowdfunding scams, we propose to use a broad range of traits including project-based traits, project creator-based ones, and content-based ones such as linguistic cues and Named Entity Recognition features, etc. We then propose to use the feature selection method called Forward Stepwise Logistic Regression, through which 17 key discriminating features (including six original and hitherto unused ones) of scam campaigns are discovered. Based on the selected 17 key features, we present and discuss our findings and insights on distinguishing characteristics of crowdfunding scams, and build our scam detection model with 87.3% accuracy. We also explore the feasibility of early scam detection, building a model with 70.2% of classification accuracy right at the time of project launch. We discuss what features from which sections are more helpful for early scam detection on day 0 and thereafter.


Asunto(s)
Colaboración de las Masas , Colaboración de las Masas/métodos
8.
J Environ Manage ; 302(Pt B): 114072, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34781050

RESUMEN

Hydrogen peroxide (H2O2) is applied in various environments. It could be present at concentrations ranging from nanomolar to micromolar in a water system. It is produced through pollutants and natural activities. Since few studies have been conducted about the impact of naturally produced H2O2 on aquatic organisms, the objective of the present study was to monitor changes in responses of aquatic model organisms such as zebrafish and antibiotic-resistant bacteria to different exogenous H2O2 exposure. Increases in exposure concentration and time induced decreases in the perception of zebrafish larvae (up to 69%) and movement of adult zebrafish (average speed, average acceleration, movement distance, and activity time) compared to the control (non-exposed group). In addition, as a function of H2O2 exposure concentration (0-100,000 nM) and time, up to 20-fold increase (p = 5.00*10-6) of lipid peroxidation compared to control was observed. For microorganisms, biofilm, an indirect indicator of resistance to external stressors, was increased up to 68% and gene transfer was increased (p = 2.00*10-6) by more than 30% after H2O2 exposure. These results imply that naturally generated H2O2 could adversely affect aquatic environment organisms and public health. Thus, more careful attention is needed for H2O2 production in an aquatic system.


Asunto(s)
Peróxido de Hidrógeno , Contaminantes Químicos del Agua , Animales , Antibacterianos/toxicidad , Bacterias/genética , Peróxido de Hidrógeno/toxicidad , Larva , Contaminantes Químicos del Agua/análisis , Pez Cebra
9.
Hum Brain Mapp ; 42(16): 5374-5396, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34415651

RESUMEN

We report that regions-of-interest (ROIs) associated with idiosyncratic individual behavior can be identified from functional magnetic resonance imaging (fMRI) data using statistical approaches that explicitly model individual variability in neuronal activations, such as mixed-effects multilevel analysis (MEMA). We also show that the relationship between neuronal activation in fMRI and behavioral data can be modeled using canonical correlation analysis (CCA). A real-world dataset for the neuronal response to nicotine use was acquired using a custom-made MRI-compatible apparatus for the smoking of electronic cigarettes (e-cigarettes). Nineteen participants smoked e-cigarettes in an MRI scanner using the apparatus with two experimental conditions: e-cigarettes with nicotine (ECIG) and sham e-cigarettes without nicotine (SCIG) and subjective ratings were collected. The right insula was identified in the ECIG condition from the χ2 -test of the MEMA but not from the t-test, and the corresponding activations were significantly associated with the similarity scores (r = -.52, p = .041, confidence interval [CI] = [-0.78, -0.17]) and the urge-to-smoke scores (r = .73, p <.001, CI = [0.52, 0.88]). From the contrast between the two conditions (i.e., ECIG > SCIG), the right orbitofrontal cortex was identified from the χ2 -tests, and the corresponding neuronal activations showed a statistically meaningful association with similarity (r = -.58, p = .01, CI = [-0.84, -0.17]) and the urge to smoke (r = .34, p = .15, CI = [0.09, 0.56]). The validity of our analysis pipeline (i.e., MEMA followed by CCA) was further evaluated using the fMRI and behavioral data acquired from the working memory and gambling tasks available from the Human Connectome Project.


Asunto(s)
Corteza Cerebral/fisiopatología , Ansia/fisiología , Neuroimagen Funcional , Tabaquismo/fisiopatología , Adulto , Corteza Cerebral/diagnóstico por imagen , Sistemas Electrónicos de Liberación de Nicotina , Femenino , Humanos , Aprendizaje Automático , Imagen por Resonancia Magnética , Masculino , Análisis Multinivel , Tabaquismo/diagnóstico por imagen , Adulto Joven
10.
BMC Anesthesiol ; 21(1): 158, 2021 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-34020595

RESUMEN

BACKGROUND: High-intensity ultrasound has been used to induce acoustic cavitation in the skin and subsequently enhances skin permeability to deliver hydrophobic topical medications including lidocaine. In contrast, instead of changing skin permeability, pulsed application of low-intensity focused ultrasound (FUS) has shown to non-invasively and temporarily disrupt drug-plasma protein binding, thus has potential to enhance the anesthetic effects of hydrophilic lidocaine hydrochloride through unbinding it from serum/interstitial α1-acid glycoprotein (AAG). METHODS: FUS, operating at fundamental frequency of 500 kHz, was applied pulse-mode (55-ms pulse duration, 4-Hz pulse repetition frequency) at a spatial-peak pulse-average intensity of 5 W/cm2. In vitro equilibrium dialysis was performed to measure the unbound concentration of lidocaine (lidocaine hydrochloride) from dialysis cassettes, one located at the sonication focus and the other outside the sonication path, all immersed in phosphate-buffered saline solution containing both lidocaine (10 µg/mL) and human AAG (5 mg/mL). In subsequent animal experiments (Sprague-Dawley rats, n = 10), somatosensory evoked potential (SSEP), elicited by electrical stimulations to the unilateral hind leg, was measured under three experimental conditions-applications of FUS to the unilateral thigh area at the site of administered topical lidocaine, FUS only, and lidocaine only. Skin temperature was measured before and after sonication. Passive cavitation detection was also performed during sonication to evaluate the presence of FUS-induced cavitation. RESULTS: Sonication increased the unbound lidocaine concentration (8.7 ± 3.3 %) from the dialysis cassette, compared to that measured outside the sonication path (P < 0.001). Application of FUS alone did not alter the SSEP while administration of lidocaine reduced its P23 component (i.e., a positive peak at 23 ms latency). The FUS combined with lidocaine resulted in a further reduction of the P23 component (in a range of 21.8 - 23.4 ms after the electrical stimulations; F(2,27) = 3.2 - 4.0, P < 0.05), indicative of the enhanced anesthetic effect of the lidocaine. Administration of FUS neither induced cavitation nor altered skin conductance or temperature, suggesting that skin permeability was unaffected. CONCLUSIONS: Unbinding lidocaine from the plasma proteins by exposure to non-thermal low-intensity ultrasound is attributed as the main mechanism behind the observation.


Asunto(s)
Anestésicos Locales/farmacología , Tratamiento con Ondas de Choque Extracorpóreas/métodos , Lidocaína/farmacología , Piel/efectos de los fármacos , Administración Tópica , Anestésicos Locales/administración & dosificación , Animales , Lidocaína/administración & dosificación , Modelos Animales , Ratas , Ratas Sprague-Dawley
11.
Sensors (Basel) ; 21(9)2021 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-34066614

RESUMEN

The rapid development in wireless technologies is positioning the Internet of Things (IoT) as an essential part of our daily lives. Localization is one of the most attractive applications related to IoT. In the past few years, localization has been gaining attention because of its applicability in safety, health monitoring, environment monitoring, and security. As a result, various localization-based wireless frameworks are being presented to improve such applications' performances based on specific key performance indicators (KPIs). Therefore, this paper explores the recently proposed localization schemes in IoT. Initially, this paper explains the major KPIs of localization. After that, a thorough comparison of recently proposed localization schemes based on the KPIs is presented. The comparison includes an overview, architecture, network structure, performance parameters, and target KPIs. At the end, possible future directions are presented for the researchers working in this domain.

12.
J Environ Manage ; 298: 113515, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34403920

RESUMEN

In water, hydrogen peroxide (H2O2) is produced through abiotic and biotic reactions with organic matter, including algal cells. The production of H2O2 is influenced by harmful algal cell communities and toxicity. However, only a few studies have been conducted on H2O2 concentrations in natural water. Particularly, the seasonal and temporal patterns of H2O2 concentration suggest that H2O2 generation from aquatic microorganisms could be identified to compare of photochemical production from dissolved organic matter. Study area is a source of raw water and is a large artificial lake located near a metropolitan city. Due to various environmental conditions, harmful algal blooms frequently occur in summer. The purpose of this study was to trace the H2O2 concentration and water quality parameters of study area where algal bloom occurs and what factors directly affect the H2O2 concentration. Experiments were performed on the influencing factors via water samples from study area and lab-scale culture tank. The lake produces an average of 553 nM H2O2, which increases by more than three times (1460 nM) in summer compared the winter. The lake (18.6-23.8 nMh-1) produced more H2O2 than streams (7.4-9.0 nMh-1) during daylight hours. All water sites presented the lowest production rates in dark conditions (1.1-1.5 nMh-1). Daytime environment increased the generation rate more than the nighttime. The trend of H2O2 produced by algal cells was similar to that of the growth of algal cells. The exposure to external substances (heavy metals and antibiotics) increased the incidence by approximately five times; antibiotics were more influential than heavy metals.


Asunto(s)
Cianobacterias , Peróxido de Hidrógeno , Floraciones de Algas Nocivas , Lagos , Estaciones del Año
13.
Pak J Pharm Sci ; 34(6): 2159-2165, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35034876

RESUMEN

Bojanggunbi-tang (BGT) is a well-known and widely used herbal prescription in Korea for colon diseases, with well-documented pharmacological effects on the digestive system. The current study aimed to develop a new simple and effective prescription using the original prescription. mBGT, a modified BGT, was developed by mixing the extracts of Lonicera japonica Thunb., Alisma orientalis and Atractylodes macrocephala based on a literature review and screening of 16 kinds of component herbs of BGT. A colitis mouse (Male, BALB/c) model was induced using dextran sulfate sodium (5%). The effects of BGT and mBGT on body weight, histological damage, clinical score, macroscopic score and colon length were compared. The mechanisms of action were analyzed based on cytokine production in colon tissue. mBGT at 300mg/kg showed similar effectiveness to that of BGT on colon shortening (P<0.01), clinical score (P<0.05), macroscopic score (P<0.01) and histological damage (P<0.01). In addition, mBGT decreased cytokines, including Interleukin 1 beta, tumor necrosis factor alpha and Interleukin 17, in a dose-dependent manner. In conclusion, mBGT could be a substitute prescription for BGT in clinics and a candidate for the development of a new BGT-based therapeutic agent against colitis.


Asunto(s)
Antiinflamatorios , Colitis , Colon , Medicamentos Herbarios Chinos , Animales , Masculino , Antiinflamatorios/farmacología , Colitis/inducido químicamente , Colitis/metabolismo , Colitis/patología , Colitis/prevención & control , Colon/efectos de los fármacos , Colon/metabolismo , Colon/patología , Citocinas/metabolismo , Sulfato de Dextran , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/farmacología , Mediadores de Inflamación/metabolismo , Ratones Endogámicos BALB C
14.
Neuroimage ; 223: 117328, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32896633

RESUMEN

Deep-learning methods based on deep neural networks (DNNs) have recently been successfully utilized in the analysis of neuroimaging data. A convolutional neural network (CNN) is a type of DNN that employs a convolution kernel that covers a local area of the input sample and moves across the sample to provide a feature map for the subsequent layers. In our study, we hypothesized that a 3D-CNN model with down-sampling operations such as pooling and/or stride would have the ability to extract robust feature maps from the shifted and scaled neuronal activations in a single functional MRI (fMRI) volume for the classification of task information associated with that volume. Thus, the 3D-CNN model would be able to ameliorate the potential misalignment of neuronal activations and over-/under-activation in local brain regions caused by imperfections in spatial alignment algorithms, confounded by variability in blood-oxygenation-level-dependent (BOLD) responses across sessions and/or subjects. To this end, the fMRI volumes acquired from four sensorimotor tasks (left-hand clenching, right-hand clenching, auditory attention, and visual stimulation) were used as input for our 3D-CNN model to classify task information using a single fMRI volume. The classification performance of the 3D-CNN was systematically evaluated using fMRI volumes obtained from various minimal preprocessing scenarios applied to raw fMRI volumes that excluded spatial normalization to a template and those obtained from full preprocessing that included spatial normalization. Alternative classifier models such as the 1D fully connected DNN (1D-fcDNN) and support vector machine (SVM) were also used for comparison. The classification performance was also assessed for several k-fold cross-validation (CV) schemes, including leave-one-subject-out CV (LOOCV). Overall, the classification results of the 3D-CNN model were superior to that of the 1D-fcDNN and SVM models. When using the fully-processed fMRI volumes with LOOCV, the mean error rates (± the standard error of the mean) for the 3D-CNN, 1D-fcDNN, and SVM models were 2.1% (± 0.9), 3.1% (± 1.2), and 4.1% (± 1.5), respectively (p = 0.041 from a one-way ANOVA). The error rates for 3-fold CV were higher (2.4% ± 1.0, 4.2% ± 1.3, and 10.1% ± 2.0; p < 0.0003 from a one-way ANOVA). The mean error rates also increased considerably using the raw fMRI 3D volume data without preprocessing (26.2% for the 3D-CNN, 75.0% for the 1D-fcDNN, and 75.0% for the SVM). Furthermore, the ability of the pre-trained 3D-CNN model to handle shifted and scaled neuronal activations was demonstrated in an online scenario for five-class classification (i.e., four sensorimotor tasks and the resting state) using the real-time fMRI of three participants. The resulting classification accuracy was 78.5% (± 1.4), 26.7% (± 5.9), and 21.5% (± 3.1) for the 3D-CNN, 1D-fcDNN, and SVM models, respectively. The superior performance of the 3D-CNN compared to the 1D-fcDNN was verified by analyzing the resulting feature maps and convolution filters that handled the shifted and scaled neuronal activations and by utilizing an independent public dataset from the Human Connectome Project.


Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/fisiología , Imagen por Resonancia Magnética/métodos , Redes Neurales de la Computación , Desempeño Psicomotor , Adulto , Atención/fisiología , Percepción Auditiva/fisiología , Humanos , Masculino , Actividad Motora , Máquina de Vectores de Soporte , Percepción Visual/fisiología , Adulto Joven
15.
Neuroimage ; 216: 116617, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32057996

RESUMEN

The naturalistic viewing of a video clip enables participants to obtain more information from the clip compared to conventional viewing of a static image. Because changing the field-of-view (FoV) allows new visual information to be obtained, we were motivated to investigate whether naturalistic viewing with varying FoV based on active eye movement can enhance the viewing experience of natural stimuli, such as those found in a video clip with a 360° FoV in an MRI scanner. To this end, we developed a novel naturalistic viewing paradigm based on real-time eye-gaze tracking while participants were watching a 360° panoramic video during fMRI acquisition. The gaze position of the participants was recorded using an eye-tracking computer and then transmitted to a stimulus presentation computer via a TCP/IP connection. The identified gaze position was then used to alter the participants' FoV of the video clip in real-time, so the participants could change their FoV to fully explore the 360° video clip (referred to in this paper as active viewing). The gaze position of one participant while watching a video was used to change the FoV of the same video clip for a paired participant (referred to as yoked or passive viewing). Four 360° panoramic videos were used as stimuli, divided into categories based on the brightness level (i.e., bright vs. dark) and location (i.e., nature vs. city). Each of the subjects participated in the active viewing of one of the two nature videos and one of the two city videos and then engaged in the passive viewing of the other video in each category, followed by conventional viewing with a fixed FoV (referred to as fixed viewing) after each of the active or passive viewings. Forty-eight healthy volunteers participated in the study, and data from 42 of these participants were used in the analysis. Representational similarity analysis (RSA) was conducted in a multiple regression framework using representational dissimilarity matrix (RDM) codes to accommodate all of the information regarding neuronal activations from fMRI analysis and the participants' subjective ratings of their viewing experience with the four video clips and with the two contrasting viewing conditions (i.e., "active-fixed" and "passive-fixed"). It was found that the participants' naturalistic viewing experience of the video clips was substantially more immersive with active viewing than with passive and fixed viewing. The RSA using the RDM codes revealed the brain regions associated with the viewing experience, including eye movement and spatial navigation in the superior frontal area (of Brodmann's area 6) and the inferior/superior parietal areas, respectively. Brain regions potentially associated with cognitive and affective processing during the viewing of the video, such as the default-mode networks and insular/Rolandic operculum areas, were also identified. To the best of our knowledge, this is the first study that has used the participants' eye movements to interactively change their FoV for 360° panoramic video clips in real-time. Our method of utilizing the MRI environment can be further extended to other environments such as electroencephalography and behavioral research. It would also be feasible to apply our method to virtual reality and/or augmented reality systems to maximize user experience based on their eye movement.


Asunto(s)
Mapeo Encefálico/métodos , Corteza Cerebral/fisiología , Movimientos Oculares/fisiología , Imagen por Resonancia Magnética/métodos , Red Nerviosa/fisiología , Percepción Visual/fisiología , Adulto , Corteza Cerebral/diagnóstico por imagen , Tecnología de Seguimiento Ocular , Femenino , Humanos , Masculino , Películas Cinematográficas , Red Nerviosa/diagnóstico por imagen , Adulto Joven
16.
J Sports Sci Med ; 19(2): 390-396, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32390733

RESUMEN

This study aimed to determine the injury patterns associated with training activities in elite South Korean aquatic sports athletes training for the Olympic Games. From 2012 to 2019, we prospectively collected data on elite aquatic sports athletes at the Korea National Training Center. The athletes were assessed by four sports medicine doctors, and data were stratified according to sex, aquatic style, injury body location, and injury severity. Chi-square tests were used to compare groups. Injury rates was expressed as rate ratios with 95% confidence intervals. Annually, the center hosts an average of 42 elite aquatic athletes spread over four aquatic styles. We recorded 797 injuries in total (annual average: 2.37 injuries/athlete), during training sessions, 57.1% of which were mild injuries. For all athletes, most injuries occurred in the upper limb (35.9%), followed by the lower limb (31.0%), the trunk (24.5%), and the head and neck (8.7%). Aquatic style significantly influenced injury body location and severity for both male and female athletes (injury body location: p < 0.001 and p < 0.010, respectively; injury severity: p = 0.027 and p < 0.001, respectively). In general, male and female athletes experienced a comparable risk of injury (rate ratio: 1.15; 95% confidence intervals: 0.53-2.46). Among the male and female South Korean elite aquatic athletes training for the Olympic Games, most injuries were mild and occurred in the upper limb, and aquatic style influenced injury body location and severity.


Asunto(s)
Traumatismos en Atletas/epidemiología , Deportes Acuáticos/lesiones , Adulto , Conducta Competitiva , Traumatismos Craneocerebrales/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Puntaje de Gravedad del Traumatismo , Extremidad Inferior/lesiones , Masculino , Traumatismos del Cuello/epidemiología , Estudios Prospectivos , República de Corea/epidemiología , Distribución por Sexo , Torso/lesiones , Extremidad Superior/lesiones , Adulto Joven
17.
Neuroimage ; 186: 607-627, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30366076

RESUMEN

An artificial neural network with multiple hidden layers (known as a deep neural network, or DNN) was employed as a predictive model (DNNp) for the first time to predict emotional responses using whole-brain functional magnetic resonance imaging (fMRI) data from individual subjects. During fMRI data acquisition, 10 healthy participants listened to 80 International Affective Digital Sound stimuli and rated their own emotions generated by each sound stimulus in terms of the arousal, dominance, and valence dimensions. The whole-brain spatial patterns from a general linear model (i.e., beta-valued maps) for each sound stimulus and the emotional response ratings were used as the input and output for the DNNP, respectively. Based on a nested five-fold cross-validation scheme, the paired input and output data were divided into training (three-fold), validation (one-fold), and test (one-fold) data. The DNNP was trained and optimized using the training and validation data and was tested using the test data. The Pearson's correlation coefficients between the rated and predicted emotional responses from our DNNP model with weight sparsity optimization (mean ±â€¯standard error 0.52 ±â€¯0.02 for arousal, 0.51 ±â€¯0.03 for dominance, and 0.51 ±â€¯0.03 for valence, with an input denoising level of 0.3 and a mini-batch size of 1) were significantly greater than those of DNN models with conventional regularization schemes including elastic net regularization (0.15 ±â€¯0.05, 0.15 ±â€¯0.06, and 0.21 ±â€¯0.04 for arousal, dominance, and valence, respectively), those of shallow models including logistic regression (0.11 ±â€¯0.04, 0.10 ±â€¯0.05, and 0.17 ±â€¯0.04 for arousal, dominance, and valence, respectively; average of logistic regression and sparse logistic regression), and those of support vector machine-based predictive models (SVMps; 0.12 ±â€¯0.06, 0.06 ±â€¯0.06, and 0.10 ±â€¯0.06 for arousal, dominance, and valence, respectively; average of linear and non-linear SVMps). This difference was confirmed to be significant with a Bonferroni-corrected p-value of less than 0.001 from a one-way analysis of variance (ANOVA) and subsequent paired t-test. The weights of the trained DNNPs were interpreted and input patterns that maximized or minimized the output of the DNNPs (i.e., the emotional responses) were estimated. Based on a binary classification of each emotion category (e.g., high arousal vs. low arousal), the error rates for the DNNP (31.2% ±â€¯1.3% for arousal, 29.0% ±â€¯1.7% for dominance, and 28.6% ±â€¯3.0% for valence) were significantly lower than those for the linear SVMP (44.7% ±â€¯2.0%, 50.7% ±â€¯1.7%, and 47.4% ±â€¯1.9% for arousal, dominance, and valence, respectively) and the non-linear SVMP (48.8% ±â€¯2.3%, 52.2% ±â€¯1.9%, and 46.4% ±â€¯1.3% for arousal, dominance, and valence, respectively), as confirmed by the Bonferroni-corrected p < 0.001 from the one-way ANOVA. Our study demonstrates that the DNNp model is able to reveal neuronal circuitry associated with human emotional processing - including structures in the limbic and paralimbic areas, which include the amygdala, prefrontal areas, anterior cingulate cortex, insula, and caudate. Our DNNp model was also able to use activation patterns in these structures to predict and classify emotional responses to stimuli.


Asunto(s)
Percepción Auditiva/fisiología , Mapeo Encefálico/métodos , Encéfalo/fisiología , Emociones/fisiología , Procesamiento de Imagen Asistido por Computador/métodos , Redes Neurales de la Computación , Máquina de Vectores de Soporte , Adulto , Encéfalo/diagnóstico por imagen , Aprendizaje Profundo , Humanos , Imagen por Resonancia Magnética , Masculino , Adulto Joven
18.
Neuroimage ; 195: 409-432, 2019 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-30953836

RESUMEN

The triple networks, namely the default-mode network (DMN), the central executive network (CEN), and the salience network (SN), play crucial roles in disorders of the brain, as well as in basic neuroscientific processes such as mindfulness. However, currently, there is no consensus on the underlying functional features of the triple networks associated with mindfulness. In this study, we tested the hypothesis that (a) the partial regression coefficient (i.e., slope): from the SN to the DMN, mediated by the CEN, would be one of the potential mindfulness features in the real-time functional magnetic resonance imaging (rtfMRI) neurofeedback (NF) setting, and (b) this slope level may be enhanced by rtfMRI-NF training. Sixty healthy mindfulness-naïve males participated in an MRI session consisting of two non-rtfMRI-runs, followed by two rtfMRI-NF runs and one transfer run. Once the regions-of-interest of each of the triple networks were defined using the non-rtfMRI-runs, the slope level was calculated by mediation analysis and used as neurofeedback information, in the form of a thermometer bar, to assist with participant mindfulness during the rtfMRI-NF runs. The participants were asked to increase the level of the thermometer bar while deploying a mindfulness strategy, which consisted of focusing attention on the physical sensations of breathing. rtfMRI-NF training was conducted as part of a randomized controlled trial design, in which participants were randomly assigned to either an experimental group or a control group. The participants in the experimental group received contingent neurofeedback information, which was obtained from their own brain signals, whereas the participants in the control group received non-contingent neurofeedback information that originated from matched participants in the experimental group. Our results indicated that the slope level from the SN to the DMN, mediated by the CEN, was associated with mindfulness score (rtfMRI-NF runs: r = 0.53, p = 0.007; p-value was corrected from 10,000 random permutations) and with task-performance feedback score (rtfMRI-NF run: r = 0.61, p = 0.001) in the experimental group only. In addition, during the rtfMRI-NF runs the level of the partial regression coefficient feature was substantially increased in the experimental group compared to the control group (p < 0.05 from the paired t-test; the p-value was corrected from 10,000 random permutations). To the best of our knowledge, this is the first study to demonstrate a partial regression coefficient feature of mindfulness in the rtfMRI-NF setting obtained by triple network mediation analysis, as well as the possibility of enhancement of the partial regression coefficient feature by rtfMRI-NF training.


Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/fisiología , Atención Plena , Neurorretroalimentación/métodos , Adulto , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Masculino
19.
Br J Sports Med ; 53(7): 430-435, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30448779

RESUMEN

OBJECTIVES: To report injury patterns associated with the training activities of elite male and female South Korean wrestling athletes preparing for the Olympic Games. METHODS: From 2008 to 2017, we prospectively collected data on elite wrestling athletes at the Korea National Training Center. Athletes were assessed by two sports medicine doctors, and data were stratified according to sex, wrestling style, weight class, injury location and injury severity. Χ2tests were used to compare groups. Injury risk was expressed in relative ratios with 95% confidence intervals (RR, 95% CI). RESULTS: There were 238 male and 75 female elite wrestlers. Training time totalled 382 800 hours. We recorded 1779 injuries in 313 athletes aged >18 years (annual average, 4.04 injuries/athlete); 59% of these were mild injuries. When all athletes were considered, most injuries occurred in the lower extremities (37.5%), followed by the upper extremities (27.4%), trunk (25.4%) and the head and neck area (9.7%). Weight class significantly influenced injury severity for both wrestling styles among male athletes (Greco-Roman, P=0.031; freestyle, P=0.028), as well as among female freestyle wrestling athletes (P=0.013). The relative ratio of injury incidence for the lightweight class compared with the heavyweight class was high for Greco-Roman style compared with freestyle (RR 1.13, 95% CI 1.03 to 1.27; P=0.011). CONCLUSIONS: Among male and female South Korean elite wrestling athletes training for the Olympic Games, most injuries were mild and occurred in the lower extremities. Weight class influenced injury severity in both wrestling styles, and lightweight athletes had higher injury rates.


Asunto(s)
Acondicionamiento Físico Humano/efectos adversos , Lucha/lesiones , Adulto , Peso Corporal , Conducta Competitiva/fisiología , Traumatismos Craneocerebrales/epidemiología , Traumatismos Craneocerebrales/prevención & control , Estudios Epidemiológicos , Femenino , Humanos , Incidencia , Puntaje de Gravedad del Traumatismo , Extremidad Inferior/lesiones , Masculino , Traumatismos del Cuello/epidemiología , Traumatismos del Cuello/prevención & control , República de Corea/epidemiología , Factores Sexuales , Torso/lesiones , Extremidad Superior/lesiones , Adulto Joven
20.
Int J Syst Evol Microbiol ; 68(4): 1233-1237, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29480794

RESUMEN

A Gram-stain-negative, non-motile, aerobic and rod-shaped or ovoid bacterial strain, designated MYP2-2T, was isolated from the intestinal tract of a squid (Todarodes pacificus) collected from the East Sea, South Korea, and subjected to a polyphasic taxonomic study. Strain MYP2-2T grew optimally at 30-35 °C and in the presence of 2.0 % (w/v) NaCl. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain MYP2-2T belonged to the genus Vitellibacter. Strain MYP2-2T exhibited 16S rRNA gene sequence similarities of 95.4-96.6 % to the type strains of Vitellibacter species and of less than 94.5 % to the type strains of other recognized species examined. Strain MYP2-2T contained menaquinone MK-6 as the predominant respiratory quinone and iso-C15 : 0 and iso-C17 : 0 3-OH as the major fatty acids. The major polar lipids detected in strain MYP2-2T were phosphatidylethanolamine and one unidentified lipid. The DNA G+C content of strain MYP2-2T was 41.6 mol%. Differential phenotypic properties, together with its phylogenetic distinctiveness, revealed that strain MYP2-2T is separated from recognized species of the genus Vitellibacter. On the basis of the data presented, strain MYP2-2T is considered to represent a novel species of the genus Vitellibacter, for which the name Vitellibacter todarodis sp. nov. is proposed. The type strain is MYP2-2T (=KCTC 62141T=NBRC 113025T).


Asunto(s)
Decapodiformes/microbiología , Flavobacteriaceae/clasificación , Intestinos/microbiología , Filogenia , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Flavobacteriaceae/genética , Flavobacteriaceae/aislamiento & purificación , Fosfatidiletanolaminas/química , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
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