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1.
Sensors (Basel) ; 24(9)2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38732846

ABSTRACT

Brain-computer interfaces (BCIs) allow information to be transmitted directly from the human brain to a computer, enhancing the ability of human brain activity to interact with the environment. In particular, BCI-based control systems are highly desirable because they can control equipment used by people with disabilities, such as wheelchairs and prosthetic legs. BCIs make use of electroencephalograms (EEGs) to decode the human brain's status. This paper presents an EEG-based facial gesture recognition method based on a self-organizing map (SOM). The proposed facial gesture recognition uses α, ß, and θ power bands of the EEG signals as the features of the gesture. The SOM-Hebb classifier is utilized to classify the feature vectors. We utilized the proposed method to develop an online facial gesture recognition system. The facial gestures were defined by combining facial movements that are easy to detect in EEG signals. The recognition accuracy of the system was examined through experiments. The recognition accuracy of the system ranged from 76.90% to 97.57% depending on the number of gestures recognized. The lowest accuracy (76.90%) occurred when recognizing seven gestures, though this is still quite accurate when compared to other EEG-based recognition systems. The implemented online recognition system was developed using MATLAB, and the system took 5.7 s to complete the recognition flow.


Subject(s)
Brain-Computer Interfaces , Electroencephalography , Gestures , Humans , Electroencephalography/methods , Face/physiology , Algorithms , Pattern Recognition, Automated/methods , Signal Processing, Computer-Assisted , Brain/physiology , Male
2.
Int J Geriatr Psychiatry ; 39(4): e6085, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38622754

ABSTRACT

OBJECTIVE: The purpose of the study is to assess if daily use of hypnotics increases mortality, aspiration pneumonia and hip fracture among relatively healthy individuals aged 75 years or older who lead independent lives in the community. METHOD AND PATIENTS: Of the adults aged 75 years or older residing in Hokkaido prefecture of Japan (n = 705,538), those who did not meet several exclusion criteria were eligible for generating propensity score-matched cohorts (n = 214,723). Exclusion criteria included co-prescribed medications acting on the central nervous system, diagnoses of malignant neoplasm, dementia, depression, etc. We compared 33,095 participants who were prescribed hypnotics for daily use (hypnotic group) with a propensity score-matched cohort without a prescription (control group). Participants were followed for more than 42 months. RESULTS: During the 42-month follow-up period, the incidence of the three outcome measures in the hypnotics group was significantly higher than that in the control group (aspiration pneumonia p < 0.001, hip fracture p = 0.007, and all-cause mortality p < 0.001). Sensitivity analyses utilizing inverse probability weighting demonstrated hazard ratios of 1.083 [1.023-1.146] for mortality, 1.117 [1.014-1.230] for aspiration pneumonia, and 1.720 [1.559-1.897] for hip fracture. Meanwhile, the attribute risk differences were 2.7, 1.5, and 1.0 per 1000 patient-years, respectively. CONCLUSIONS: Although daily use of hypnotics increased the risk of three events, their attribute risk differences were fewer than 3.0 per 1000 patient-years. The results will help provide guidance on whether it is reasonable to prescribe hypnotics to geriatric population aged 75 or older leading independent lives in the community. CLINICAL TRIAL REGISTRATION: UMIN-CTR UMIN000048398.


Subject(s)
Hip Fractures , Pneumonia, Aspiration , Humans , Aged , Hypnotics and Sedatives/adverse effects , Independent Living , Retrospective Studies , Cohort Studies , Japan/epidemiology , Risk Factors , Hip Fractures/epidemiology
4.
Chemistry ; 30(29): e202400894, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38494436

ABSTRACT

We report here on the facile synthesis of amino- and alkoxy-λ3-iodanes supported by a benziodoxole (BX) template and their use as arynophiles. The amino- and alkoxy-BX derivatives can be readily synthesized by reacting the respective amines or alcohols with chlorobenziodoxole in the presence of a suitable base. Unlike previously known nitrogen- and oxygen-bound iodane compounds, which have primarily been employed as electrophilic group transfer agents or oxidants, the present amino- and alkoxy-BX reagents manifest themselves as nucleophilic amino and alkoxy transfer agents toward arynes. This reactivity leads to the aryne insertion into the N-I(III) or O-I(III) bond to afford ortho-amino- and ortho-alkoxy-arylbenziodoxoles, iodane compounds nontrivial to procure by existing methods. The BX group in these insertion products exhibits excellent leaving group ability, enabling diverse downstream transformations.

5.
Phys Rev Lett ; 130(15): 153402, 2023 Apr 14.
Article in English | MEDLINE | ID: mdl-37115891

ABSTRACT

We observe a weakly allowed optical transition of atomic ytterbium from the ground state to the metastable state 4f^{13}5d6s^{2} (J=2) for all five bosonic and two fermionic isotopes with resolved Zeeman and hyperfine structures. This inner-shell orbital transition has been proposed as a new frequency standard as well as a quantum sensor for new physics. We find magic wavelengths through the measurement of the scalar and tensor polarizabilities and reveal that the measured trap lifetime in a three-dimensional optical lattice is 1.9(1) s, which is crucial for precision measurements. We also determine the g factor by an interleaved measurement, consistent with our relativistic atomic calculation. This work opens the possibility of an optical lattice clock with improved stability and accuracy as well as novel approaches for physics beyond the standard model.

6.
JMIR Res Protoc ; 12: e44275, 2023 Apr 11.
Article in English | MEDLINE | ID: mdl-37040162

ABSTRACT

BACKGROUND: Digital health technologies using mobile apps and wearable devices are a promising approach to the investigation of substance use in the real world and for the analysis of predictive factors or harms from substance use. Moreover, consecutive repeated data collection enables the development of predictive algorithms for substance use by machine learning methods. OBJECTIVE: We developed a new self-monitoring mobile app to record daily substance use, triggers, and cravings. Additionally, a wearable activity tracker (Fitbit) was used to collect objective biological and behavioral data before, during, and after substance use. This study aims to describe a model using machine learning methods to determine substance use. METHODS: This study is an ongoing observational study using a Fitbit and a self-monitoring app. Participants of this study were people with health risks due to alcohol or methamphetamine use. They were required to record their daily substance use and related factors on the self-monitoring app and to always wear a Fitbit for 8 weeks, which collected the following data: (1) heart rate per minute, (2) sleep duration per day, (3) sleep stages per day, (4) the number of steps per day, and (5) the amount of physical activity per day. Fitbit data will first be visualized for data analysis to confirm typical Fitbit data patterns for individual users. Next, machine learning and statistical analysis methods will be performed to create a detection model for substance use based on the combined Fitbit and self-monitoring data. The model will be tested based on 5-fold cross-validation, and further preprocessing and machine learning methods will be conducted based on the preliminary results. The usability and feasibility of this approach will also be evaluated. RESULTS: Enrollment for the trial began in September 2020, and the data collection finished in April 2021. In total, 13 people with methamphetamine use disorder and 36 with alcohol problems participated in this study. The severity of methamphetamine or alcohol use disorder assessed by the Drug Abuse Screening Test-10 or the Alcohol Use Disorders Identification Test-10 was moderate to severe. The anticipated results of this study include understanding the physiological and behavioral data before, during, and after alcohol or methamphetamine use and identifying individual patterns of behavior. CONCLUSIONS: Real-time data on daily life among people with substance use problems were collected in this study. This new approach to data collection might be helpful because of its high confidentiality and convenience. The findings of this study will provide data to support the development of interventions to reduce alcohol and methamphetamine use and associated negative consequences. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/44275.

7.
Nat Commun ; 12(1): 6724, 2021 Nov 18.
Article in English | MEDLINE | ID: mdl-34795240

ABSTRACT

Quantum transport is ubiquitous in physics. So far, quantum transport between terminals has been extensively studied in solid state systems from the fundamental point of views such as the quantized conductance to the applications to quantum devices. Recent works have demonstrated a cold-atom analog of a mesoscopic conductor by engineering a narrow conducting channel with optical potentials, which opens the door for a wealth of research of atomtronics emulating mesoscopic electronic devices and beyond. Here we realize an alternative scheme of the quantum transport experiment with ytterbium atoms in a two-orbital optical lattice system. Our system consists of a multi-component Fermi gas and a localized impurity, where the current can be created in the spin space by introducing the spin-dependent interaction with the impurity. We demonstrate a rich variety of localized-impurity-induced quantum transports, which paves the way for atomtronics exploiting spin degrees of freedom.

8.
Hum Cell ; 34(2): 634-643, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33454890

ABSTRACT

Mammalian cells take in D-glucose as an essential fuel as well as a carbon source. In contrast, L-glucose, the mirror image isomer of D-glucose, has been considered merely as a non-transportable/non-metabolizable control for D-glucose. We have shown that 2-[N-(7-Nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-D-glucose (2-NBDG), a D-glucose analogue combining a fluorophore NBD at the C-2 position, is useful as a tracer for monitoring D-glucose uptake through glucose transporters (GLUTs) into mammalian cells. To more precisely evaluate the stereoselectivity of 2-NBDG uptake, we developed an L-glucose analogue 2-NBDLG, the mirror-image isomer of 2-NBDG. Interestingly, 2-NBDLG was taken up into mouse insulinoma MIN6 cells showing nuclear heterogeneity, a cytological feature of malignancy, while remaining MIN6 cells only exhibited a trace amount of 2-NBDLG uptake. The 2-NBDLG uptake into MIN6 cells was abolished by phloretin, but persisted under blockade of major mammalian glucose transporters. Unfortunately, however, no such uptake could be detected in other tumor cell lines. Here we demonstrate that human osteosarcoma U2OS cells take in 2-NBDLG in a phloretin-inhibitable manner. The uptake of 2-NBDG, and not that of 2-NBDLG, into U2OS cells was significantly inhibited by cytochalasin B, a potent GLUT inhibitor. Phloretin, but neither phlorizin, an inhibitor of sodium-glucose cotransporter (SGLT), nor a large amount of D/L-glucose, blocked the 2-NBDLG uptake. These results suggest that a phloretin-inhibitable, non-GLUT/non-SGLT, possibly non-transporter-mediated yet unidentified mechanism participates in the uptake of the fluorescent L-glucose analogue in two very different tumor cells, the mouse insulinoma and the human osteosarcoma cells.


Subject(s)
4-Chloro-7-nitrobenzofurazan/analogs & derivatives , Bone Neoplasms/metabolism , Deoxyglucose/analogs & derivatives , Glucose/metabolism , Osteosarcoma/metabolism , Phloretin/pharmacology , 4-Chloro-7-nitrobenzofurazan/metabolism , Animals , Cytochalasin B/pharmacology , Deoxyglucose/metabolism , Depression, Chemical , Glucose Transport Proteins, Facilitative/antagonists & inhibitors , Glucose Transport Proteins, Facilitative/metabolism , Humans , Insulinoma/metabolism , Isomerism , Mice , Pancreatic Neoplasms/metabolism , Sodium-Glucose Transporter 2 Inhibitors/pharmacology , Tumor Cells, Cultured
9.
Cancers (Basel) ; 12(4)2020 Apr 01.
Article in English | MEDLINE | ID: mdl-32244695

ABSTRACT

Cancerous tumors comprise cells showing metabolic heterogeneity. Among numerous efforts to understand this property, little attention has been paid to the possibility that cancer cells take up and utilize otherwise unusable substrates as fuel. Here we discuss this issue by focusing on L-glucose, the mirror image isomer of naturally occurring D-glucose; L-glucose is an unmetabolizable sugar except in some bacteria. By combining relatively small fluorophores with L-glucose, we generated fluorescence-emitting L-glucose tracers (fLGs). To our surprise, 2-NBDLG, one of these fLGs, which we thought to be merely a control substrate for the fluorescent D-glucose tracer 2-NBDG, was specifically taken up into tumor cell aggregates (spheroids) that exhibited nuclear heterogeneity, a major cytological feature of malignancy in cancer diagnosis. Changes in mitochondrial activity were also associated with the spheroids taking up fLG. To better understand these phenomena, we review here the Warburg effect as well as key studies regarding glucose uptake. We also discuss tumor heterogeneity involving aberrant uptake of glucose and mitochondrial changes based on the data obtained by fLG. We then consider the use of fLGs as novel markers for visualization and characterization of malignant tumor cells.

10.
In Vivo ; 30(2): 107-11, 2016.
Article in English | MEDLINE | ID: mdl-26912820

ABSTRACT

BACKGROUND: Previous studies have shown activity against viruses, bacteria, inflammation and oral lichenoid dysplasia of alkaline extract of the leaves of Sasa senanensis Rehder (SE), suggesting its possible application to oral diseases. In the present study, we performed a small-scale clinical test to investigate whether SE is effective against halitosis and in oral bacterial reduction. MATERIALS AND METHODS: A total of 12 volunteers participated in this study. They brushed their teeth immediately after meals three times each day with SE-containing toothpaste (SETP) or placebo toothpaste. Halitosis in the breath and bacterial number on the tongue were measured by commercially available portable apparatuses at a specified time in the morning. RESULTS: Some relationship was observed between halitosis and bacterial number from each individual, especially when those with severe halitosis were included. Repeated experiments demonstrated that SETP significantly reduced halitosis but not the bacterial number on the tongue. CONCLUSION: The present study provides for the first time the basis for anti-halitosis activity of SE.


Subject(s)
Halitosis/drug therapy , Plant Extracts/pharmacology , Plant Leaves/chemistry , Sasa/chemistry , Toothpastes/pharmacology , Adult , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/pharmacology , Bacterial Load/drug effects , Female , Humans , Male , Middle Aged , Plant Extracts/administration & dosage , Tongue/drug effects , Tongue/microbiology , Toothpastes/administration & dosage , Toothpastes/chemistry , Young Adult
12.
Hum Cell ; 29(1): 37-45, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26553070

ABSTRACT

Of two stereoisomers of glucose, only D- and not L-glucose is abundantly found in nature, being utilized as an essential fuel by most organisms. The uptake of D-glucose into mammalian cells occurs through glucose transporters such as GLUTs, and this process has been effectively monitored by a fluorescent D-glucose derivative 2-[N-(7-Nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-D-glucose (2-NBDG) at the single cell level. However, since fluorescence is an arbitrary measure, we have developed a fluorescent analog of L-glucose 2-[N-(7-Nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-L-glucose (2-NBDLG), as a negative control substrate for more accurately identifying the stereoselectivity of the uptake. Interestingly, a small portion of mouse insulinoma cells MIN6 abundantly took up 2-NBDLG at a late culture stage (≳ 10 days in vitro, DIV) when multi-cellular spheroids exhibiting heterogeneous nuclei were formed, whereas no such uptake was detected at an early culture stage (≲ 6 DIV). The 2-NBDLG uptake was persistently observed in the presence of a GLUT inhibitor cytochalasin B. Neither D- nor L-glucose in 50 mM abolished the uptake. No significant inhibition was detected by inactivating sodium/glucose cotransporters (SGLTs) with Na(+)-free condition. To our surprise, the 2-NBDLG uptake was totally inhibited by phloretin, a broad spectrum inhibitor against transporters/channels including GLUTs and aquaporins. From these, a question might be raised if non-GLUT/non-SGLT pathways participate in the 2-NBDLG uptake into spheroid-forming MIN6 insulinoma. It might also be worthwhile investigating whether 2-NBDLG can be used as a functional probe for detecting cancer, since the nuclear heterogeneity is among critical features of malignancy.


Subject(s)
4-Chloro-7-nitrobenzofurazan/analogs & derivatives , Deoxyglucose/analogs & derivatives , Insulinoma/metabolism , Pancreatic Neoplasms/metabolism , Phloretin/metabolism , 4-Chloro-7-nitrobenzofurazan/metabolism , Animals , Deoxyglucose/metabolism , Fluorescence , Mice , Microscopy, Confocal/methods , Molecular Imaging/methods , Tumor Cells, Cultured
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