ARID5B is a negative modulator of IL-6 production in rheumatoid arthritis synovial fibroblasts.

Recent single-cell RNA-sequencing analysis of rheumatoid arthritis (RA) synovial tissues revealed the heterogeneity of RA synovial fibroblasts (SFs) with distinct functions such as high IL-6 production. The molecular mechanisms responsible for high IL-6 production will become a promising drug target of RASFs to treat RA. In this study, we performed siRNA screening of 65 transcription factors (TFs) differentially expressed among RASF subsets to identify TFs involved in IL-6 production. The siRNA screening identified 7 TFs including ARID5B, a RA risk gene, that affected IL-6 production. Both long and short isoforms of ARID5B were expressed and negatively regulated by TNF-α in RASFs. The siRNA knockdown and lentiviral overexpression of long and short isoforms of ARID5B revealed that the long isoform suppressed IL-6 production stimulated with TNF-α. eQTL analysis using 58 SFs demonstrated that RA risk allele, rs10821944, in intron 4 of the ARID5B gene had a trend of eQTL effects to the expression of long isoform of ARID5B in SFs treated with TNF-α. ARID5B was found to be a negative modulator of IL-6 production in RASFs. The RA risk allele of ARID5B intron may cause high IL-6 production, suggesting that ARID5B will become a promising drug target to treat RA.

Effect of physical frailty on maximum phonation time in community-dwelling older individuals who visited a neurology outpatient clinic.

BACKGROUND: Maximum phonation time (MPT) is used to assess speech and other oral rehabilitation-related issues. Various factors contribute to MPT decline in older individuals. Although the impact of physical frailty on MPT has been suggested, this has not been conclusively determined. OBJECTIVE: To examine the relationship between MPT and physical frailty in community-dwelling individuals aged ≥60 years who were independently mobile. MPT-associated factors were investigated. METHODS: This cross-sectional study analysed the clinical data of 122 patients (age [interquartile range]: 80.0 [74.0-83.0] years) without dementia who visited a neurology department between 1 February 2021 and 31 January 2023. Investigated factors included age, sex, weight, height, body mass index, smoking history, grip strength, functional independence measure, vital capacity, oral diadochokinesis, MPT and the Japanese Cardiovascular Health Study score. Physical frailty was assessed based on the total score from five items (weight loss, weakness, exhaustion, slowness and low physical activity). The relationship between MPT and physical frailty was examined using Spearman's rank correlation coefficient and hierarchical multiple regression analysis. RESULTS: The MPT was negatively correlated with age (r = -0.347, p < .01) and physical frailty (r = -0.681, p < .01) and positively correlated with vital capacity (r = 0.474, p < .01) and height (r = 0.248, p < .01). The hierarchical multiple regression analysis, conducted with MPT as the dependent variable, demonstrated that physical frailty (ß = -.59, 95% confidence interval: -0.74 to 0.43, p < .001) had a strong influence on MPT. CONCLUSION: In older individuals, MPT is associated with physical frailty. When assessing MPT in clinical settings, it is advisable to perform a concurrent assessment of physical frailty.

Is polypharmacy a risk factor for aspiration pneumonia in older adults? A case-control study.

INTRODUCTION: The incidence of aspiration pneumonia and the number of medicines prescribed increase with older age. Many medicines pose a risk for aspiration pneumonia, especially those that decrease swallowing function. Older adults with polypharmacy often receive a combination of these medicines. This study aimed to clarify whether polypharmacy is a risk factor for aspiration pneumonia. METHODS: Older adults aged ≥ 65 years receiving oral medicines were included in this case-control study. Patients hospitalized for pneumonia served as the case group, and other age-matched hospitalized patients served as the control group. Patient data were collected retrospectively, and logistic regression analysis was performed using items that showed significant differences in the univariate analysis as explanatory variables. RESULTS: Logistic regression analysis revealed that the number of medicines was not a risk factor for aspiration pneumonia; however, it was associated with the Functional Oral Intake Scale score, male sex, body mass index, and number of comorbidities. CONCLUSION: Although polypharmacy is often defined only by the number of medicines, it is not a risk factor for aspiration pneumonia. A detailed comparison of prescription medicines between the pneumonia and non-pneumonia groups is necessary.

Influence of Excitation Frequency on the Performance of Peripheral Blood Flow Imaging using Electrical Impedance Tomography.

This paper presents a method for selecting the efficient excitation frequency of Electrical Impedance Tomography (EIT) for imaging peripheral blood flow with high spatial-temporal performance. Using a simulation study, we selected the excitation frequency of 16 kHz to visualize the pulsation of arteries with a high sensitivity. We then conducted a subjective study using 16 electrodes and showed that the conductivity distribution is similar to the anatomical structure of the forearm. Moreover, the integrated conductivity spectrum showed a peak corresponding to a heart rate measurement obtained using a PPG sensor at the fingertip. Therefore, we conclude that this system can capture the spatial-temporal signals related to peripheral artery blood flow by using the selected excitation frequency.

Wearable Skin Resistance-based Tomographic Sensor for Imaging Contact Pressure Distribution on the Human Body.

This study aims to develop a flexible and thin tactile sensor that can capture the contact pressure distribution on the human body. We, therefore, propose a contact resistance-based tomographic tactile sensor that uses the skin as part of the detector. We first evaluated force sensitivity to show that using the skin as a probing layer is possible. We then developed a flexible detector that is 40 mm × 80 mm in size, 200 µm thickness and uses 16 electrodes. As a result, we successfully demonstrated that the proposed method enabled the detection of the contact position within an error of 12.5 % by using frequencies higher than 1 kHz.

Optimization of electrode positions for equalizing local spatial performance of a tomographic tactile sensor.

A tomographic tactile sensor based on the contact resistance of conductors is a high sensitive pressure distribution imaging method and has advantages on the flexibility and scalability of device. While the addition of internal electrodes improves the sensor's spatial resolution, there still remain variations in resolution that depend on the contact position. In this study, we propose an optimization algorithm for electrode positions that improves entire spatial resolution by compensating for local variations in spatial resolution. Simulation results for sensors with 16 or 64 electrodes show that the proposed algorithm improves performance to 0.81 times and 0.93 times in the worst spatial resolution region of the detection area compared to equally spaced grid electrodes. The proposed methods enable tomographic tactile sensors to detect contact pressure distribution more accurately than the conventional methods, providing high-performance tactile sensing for many applications.

Metabolic and ventilatory changes during postural change from the supine position to the reclining position in bedridden older patients.

The prevention of pneumonia in bedridden older patients is important, and its recurrence in these patients is a relevant issue. Patients who are bedridden and inactive, and have dysphagia are considered to be at risk for pneumonia. Efforts to reduce the bedridden state and low activity may be necessary to reduce the risk of developing pneumonia in bedridden older patients. This study aimed to clarify the effects of postural change from the supine position to the reclining position on metabolic and ventilatory parameters and on safety in bedridden older patients. Using a breath gas analyzer and other tools, we assessed the following 3 positions: lying on the back (supine), resting in the Fowler position (Fowler), and resting in an 80° recline wheelchair (80°). Measurements were oxygen uptake, carbon dioxide output, gas exchange ratio, tidal volume (VT), minute volume, respiratory rate, inspiratory time, expiratory time, total respiratory time, mean inspiratory flow, metabolic equivalents, end-expiratory oxygen, and end-expiratory carbon dioxide as well as various vital signs. The study analysis included 19 bedridden participants. The change in oxygen uptake driven by changing the posture from the supine position to the Fowler position was as small as 10.8 mL/minute. VT significantly increased from the supine position (398.4 ±â€…111.2 mL) to the Fowler position (426.9 ±â€…106.8 mL) (P  = .037) and then showed a decreasing trend in the 80° position (416.8 ±â€…92.5 mL). For bedridden older patients, sitting in a wheelchair is a very low-impact physical activity, similar to that in normal people. The VT of bedridden older patients was maximal in the Fowler position, and the ventilatory volume did not increase with an increasing reclining angle, unlike that in normal people. These findings suggest that appropriate reclining postures in clinical situations can promote an increase in the ventilatory rate in bedridden older patients.

Slider Sheet Detection in Charge-Induction Electrostatic Film Actuators.

This work analyzes a built-in slider detection method for a charge-induction type electrostatic film actuator with a high surface-resistance slider. In the detection method, one stator electrode is detached from the parallel driving electrodes and is dedicated to sensing. When a slider with induced charges moves over the sensing electrode, electrostatic induction occurs in the sensing electrode, which causes an electric current. The current is converted to a voltage through a detection resistance, which will be an output of the sensing circuit. This paper provides a framework to analyze the output signal waveform and shows that the waveform consists of two components. One component is caused by driving voltage and appears regardless of the existence of a slider. The other component corresponds to the movement of a slider, which appears only when a slider is moving over the sensing electrode. Therefore, the slider can be detected by monitoring the latter component. The two components generally overlap, which makes the detection of the latter component difficult in some cases. This paper proposes a method to decouple the two components by switching the detection resistance at an appropriate time. These methods are verified using a prototype actuator that has an electrode pitch of 0.6 mm. The actuator was driven with a set of pulse voltages with an amplitude of 1000 V. The experimental results show similar waveforms to the analytical results, verifying the proposed analytical framework. The performance of the sensing method as a proximity sensor was verified in the experiments, and it was confirmed that the slider can be detected when it approaches the sensing electrode within about 3 mm.

Therapeutic Effect of Cyclin-Dependent Kinase 4/6 Inhibitor on Dermal Fibrosis in Murine Models of Systemic Sclerosis.

OBJECTIVE: One of the histologic characteristics of systemic sclerosis (SSc) is an increased number of dermal myofibroblasts, and transforming growth factor ß (TGFß) plays a crucial role in the promotion of myofibroblast differentiation from fibroblasts, leading to dermal fibrosis. This study was undertaken to 1) examine whether inhibition of the cell cycle with a cyclin-dependent kinase 4/6 (CDK4/6) inhibitor suppresses the proliferation of fibroblasts and their differentiation into myofibroblasts, and 2) assess the therapeutic effects of a CDK4/6 inhibitor, administered as monotherapy or in combination with a TGFß receptor (TGFßR) inhibitor, on dermal fibrosis in murine models of SSc. METHODS: Fibroblasts obtained from the skin of patients with SSc were cultured in the presence or absence of TGFß. The effects of palbociclib, a CDK4/6 inhibitor, on fibroblast proliferation and TGFß-induced differentiation into myofibroblasts were examined using bromodeoxyuridine uptake assays as well as immunofluorescence and immunoblotting analyses. Murine models of HOCl- and bleomycin-induced dermal fibrosis were used to study the effect of a CDK4/6 inhibitor on dermal fibrosis, with the CDK4/6 inhibitor treatment administered as monotherapy or in combination with galunisertib, a TGFßR inhibitor. RESULTS: Addition of a CDK4/6 inhibitor to the cell cultures suppressed the proliferation of human dermal SSc fibroblasts and their TGFß-induced differentiation into myofibroblasts, without inhibiting canonical and noncanonical TGFß signals. In murine models of dermal fibrosis, treatment of mice with a CDK4/6 inhibitor decreased dermal thickness and collagen content, as well as dermal fibroblast proliferation and the numbers of myofibroblasts. Combination therapy with the CDK4/6 inhibitor and TGFßR inhibitor resulted in additive antifibrotic effects. Mechanistically, the CDK4/6 inhibitor suppressed the expression of cellular communication network 2 and cadherin-11, which are proteins that have important roles in the development and progression of fibrosis. CONCLUSION: Results of this study demonstrate the therapeutic effect of a CDK4/6 inhibitor on dermal fibrosis when administered as monotherapy or in combination with a TGFßR inhibitor. CDK4/6 inhibitors, including palbociclib used in the present study, may represent novel agents for the treatment of SSc, which, if used in combination with a TGFßR inhibitor, might result in increased efficacy.

Chondroprotective effects of CDK4/6 inhibition via enhanced ubiquitin-dependent degradation of JUN in synovial fibroblasts.

OBJECTIVE: Targeting synovial fibroblasts (SF) using a cyclin-dependent kinase (CDK) 4/6 inhibitor (CDKI) could be a potent therapy for RA via inhibition of proliferation and MMP-3 production. This study was designed to elucidate the mechanism of chondroprotective effects on SFs by CDK 4/6 inhibition. METHODS: CDK4/6 activity was inhibited using CDKI treatment or enhanced by adenoviral gene transduction. Chondroprotective effects were evaluated using a collagen-induced arthritis model (CIA). Gene and protein expression were evaluated with quantitative PCR, ELISA and Western blotting. The binding of nuclear extracts to DNA was assessed with an electrophoresis mobility shift assay. RNA-Seq was performed to identify gene sets affected by CDKI treatment. RESULTS: CDKI attenuated cartilage destruction and MMP-3 production in CIA. In RASFs, CDKI impaired the binding of AP-1 components to DNA and inhibited the production of MMP-1 and MMP-3, which contain the AP-1 binding sequence in their promoter. CDK4/6 protected JUN from proteasome-dependent degradation by inhibiting ubiquitination. The RNA-Seq analysis identified CDKI-sensitive inflammatory genes, which were associated with the pathway of RA-associated genes, cytokine-cytokine receptor interaction and IL-17 signalling. Notably, the AP-1 motif was enriched in these genes. CONCLUSION: The mechanism of chondroprotective effects by CDK4/6 inhibition was achieved by the attenuation of AP-1 transcriptional activity via the impaired stability of JUN. Because the pharmacologic inhibition of CDK4/6 has been established as tolerable in cancer treatment, it could also be beneficial in patients with RA due to its chondroprotective and anti-inflammatory effects.

Arterial and Venous Thrombosis Complicated in COVID-19: A Retrospective Single Center Analysis in Japan.

Background: Thrombosis is a characteristic complication in coronavirus disease 2019 (COVID-19). Since coagulopathy has been observed over the entire clinical course, thrombosis might be a clue to understanding the specific pathology in COVID-19. Currently, there is limited epidemiological data of COVID-19-associated thrombosis in the Japanese population and none regarding variant strains of SARS-CoV-2. Here, we elucidate the risk factors and the pattern of thrombosis in COVID-19 patients. Methods: The patients consecutively admitted to Tokyo Medical and Dental University Hospital with COVID-19 were retrospectively analyzed. SARS-CoV-2 variants of concern/interest (VOC/VOI) carrying the spike protein mutants E484K, N501Y, or L452R were identified by PCR-based analysis. All thrombotic events were diagnosed by clinical symptoms, ultrasonography, and/or radiological tests. Results: Among the 516 patients, 32 patients experienced 42 thromboembolic events. Advanced age, severe respiratory conditions, and several abnormal laboratory markers were associated with the development of thrombosis. While thrombotic events occurred in 13% of the patients with a severe respiratory condition, those events still occurred in 2.5% of the patients who did not require oxygen therapy. Elevated D-dimer and ferritin levels on admission were independent risk factors of thrombosis (adjusted odds ratio 9.39 and 3.11, 95% confidence interval 2.08-42.3, and 1.06-9.17, respectively). Of the thrombotic events, 22 were venous, whereas 20 were arterial. While patients with thrombosis received anticoagulation and antiinflammatory therapies with a higher proportion, the mortality rate, organ dysfunctions, and bleeding complications in these patients were higher than those without thrombosis. The incidence of thrombosis in COVID-19 became less frequent over time, such as during the replacement of the earlier strains of SARS-CoV-2 by VOC/VOI and during increased use of anticoagulatory therapeutics. Conclusion: This study elucidated that elevated D-dimer and ferritin levels are useful biomarkers of thrombosis in COVID-19 patients. The comparable incidence of arterial thrombosis with venous thrombosis and the development of thrombosis in less severe patients required further considerations for the management of Japanese patients with COVID-19. Further studies would be required to identify high-risk populations and establish appropriate interventions for thrombotic complications in COVID-19.

Validity of a novel respiratory rate monitor comprising stretchable strain sensors during a 6-min walking test in patients with chronic pulmonary obstructive disease.

BACKGROUND: Breathing frequency is rarely measured during a field walking test since the current monitoring system using a face mask is cumbersome for older adults. For effective clinical application, we aimed to validate the new respiratory monitor using wearable strain sensors during a 6-min walk test (6MWT) in young adults and patients with chronic obstructive pulmonary disease (COPD). METHODS: The study included young adults and patients with stable COPD voluntarily recruited from three hospitals. Breathing frequency during 6MWT were measured by the strain sensor and a nasal capnometer. Total breathing frequencies were measured by the capnometer. The Bland-Altman method was used to estimate the mean limit of agreement for breathing frequency. RESULTS: A total of 23 young adults (age = 23.1 ± 3.7, mean ± SD) and 50 patients with COPD (age = 75.2 ± 7.2, %FEV1 = 59.1 ± 19.7) were analyzed. During the entire test period, the total breathing frequencies were measured based on an average of 252 ± 46 breaths, and the total breathing frequency was higher in patients with COPD than in young adults (mean difference = -3.349, p < 0.0013). The mean difference in breathing frequency between the strain sensors and capnometer was -0.28 (95%CI: 0.75 to 0.20), and the limit of agreement ranged from -4.1 to 3.6. The CI of the limit of agreement included the limit of equivalence (4 counts/min). CONCLUSIONS: The novel respiratory monitor with wearable sensors achieved the target accuracy in both young adults and patients with COPD in the 6MWT.

Impact of physical frailty on the clinical outcomes of older patients hospitalized for pneumonia.

AIM: This study aimed to assess the association between physical frailty and clinical outcomes among older patients hospitalized for pneumonia. METHODS: This study examined 852 consecutive patients hospitalized for pneumonia between October 2018 and September 2020. Patients who were <65 years old, scheduled for admission, did not receive inpatient rehabilitation, or died during admission were excluded. A short physical performance battery (SPPB) test was performed by physical therapists upon discharge. The primary outcome measure was a composite endpoint of readmission or mortality due to any cause within 6 months of discharge. RESULTS: In total, 521 patients (median age, 80 years; interquartile range, 74-86 years) were included in the analyses, and were divided into the following two groups: robust group with SPPB scores >9 (n = 150), and physical frailty group with SPPB scores ≤9 (n = 371). Of these, 346 (66.4%) patients were men; and the median SPPB score was 6 (interquartile range, 1-10). During the median follow-up period of 53 days (interquartile range, 4-180 days), 92 (17.6%) patients were readmitted and 25 (4.8%) patients died. Patients with physical frailty were at an increased risk for the primary endpoint (hazard ratio, 2.21; 95% confidence interval, 1.44-3.41; P < 0.001); the risk remained significant after adjusting for multiple variables (adjusted hazard ratio, 1.70; 95% confidence interval, 1.05-2.74; P = 0.028). CONCLUSIONS: Among older patients with pneumonia, physical frailty status at discharge was an independent risk factor for readmission and mortality within 6 months after initial discharge. Geriatr Gerontol Int 2021; 21: 926-931.

Pressure Stimulus to the Palm Substitutes and Augments Force Sensation.

Studies on pseudo-force feedback have reported that tactile stimuli such as skin stretch and pressure can substitute force sensation. This effect has enabled the design of a compact haptic device. However, little is known about the effect of applying pressure to the palm in terms of force substitution and augmentation, especially regarding how active and passive pressure stimuli differ. This article examines the pseudo-force effect of pressure stimuli to the palm, focusing on how it is perceived when it is applied together with a force stimulus. The method of adjustment was utilized, by which participants voluntarily moved their hands to adjust the pressure and force stimuli. The participants did this such that they felt a force equivalent to that of the reference applied to the other hand, which induced only a force stimulus. The results showed that the force sensation was significantly changed by the pressure stimulus to the palm, showing the effect of force substitution and augmentation. Furthermore, we found that there is no significant difference between the active and passive stimuli.

Reliability and Validity of the Japanese Version of the Barthel Index Dyspnea Among Patients with Respiratory Diseases.

Purpose: Japan has only a few respiratory disease-specific activity of daily living scales that are accepted outside of Japan, and they are not widely used. The Barthel Index dyspnea (BI-d), an improved version of the Barthel Index (BI), may be popular in Japan. The purpose of this study was to develop the Japanese version of BI-d (J-BI-d) and investigate its reliability and validity. Patients and Methods: The J-BI-d was developed using the basic guidelines for scale translation. The study included patients with chronic respiratory disease, receiving outpatient care at two centers between January 2019 and February 2020. Scores on the J-BI-d, modified Medical Research Council scale (mMRC scale), BI, respiratory function tests, and 6-minute walk distance (6MWD) test were measured. To verify the test-retest reliability, the J-BI-d was re-administered, and the intraclass correlation coefficient (ICC) was obtained. Internal consistency was verified by Cronbach's alpha reliability coefficient, and criterion-related validity was verified through a correlation analysis of the J-BI-d with mMRC scale and 6MWD test. Divergent validity was verified through correlation analysis between the J-BI-d and BI. Results: Data for 57 participants (mean age 74.4 ± 8.3 years) were analyzed, and reliability testing was performed with 42 of them. The mean time to retest was 8.1 ± 3.0 days, and the ICC (2, 1) was 0.76 (95% CI: 0.62-0.85), indicating high reliability. Cronbach's alpha reliability coefficient was 0.81, indicating high internal consistency. Correlation coefficients of the J-BI-d with 6MWD test (r = -0.46, p < 0.01) and mMRC scale (ρ = 0.76, p < 0.01) indicated high criterion-related validity. The J-BI-d and BI had a weak negative correlation (r = -0.29, p < 0.05), indicating high divergent validity. Conclusion: The results of this study demonstrate high reliability and appropriate validity of the J-BI-d in patients with chronic respiratory disease.

Tomographic Proximity Imaging Using Conductive Sheet for Object Tracking.

This paper proposes a proximity imaging sensor based on a tomographic approach with a low-cost conductive sheet. Particularly, by defining capacitance density, physical proximity information is transformed into electric potential. A novel theoretical model is developed to solve the capacitance density problem using the tomographic approach. Additionally, a prototype is built and tested based on the model, and the system solves an inverse problem for imaging the capacitance density change that indicates the object's proximity change. In the evaluation test, the prototype reaches an error rate of 10.0-15.8% in horizontal localization at different heights. Finally, a hand-tracking demonstration is carried out, where a position difference of 33.8-46.7 mm between the proposed sensor and depth camera is achieved at 30 fps.

New method for visualizing the dose rate distribution around the Fukushima Daiichi Nuclear Power Plant using artificial neural networks.

This study proposes a new method of visualizing the ambient dose rate distribution using artificial neural networks (ANNs) from airborne radiation monitoring results. The method was applied to the results of the airborne radiation monitoring which was conducted around the Fukushima Daiichi Nuclear Power Plant by an unmanned aerial vehicle. Much of the survey data obtained in the past were used as the training data for building a network. The number of training cases was related to the error between the ground and converted values by the ANN. The quantitative evaluation index (the root-mean-square error) between the ANN-converted value and the ground-based survey result converged at 200 training cases. This number of training case was considered a rough criterion of the required number of training cases. The reliability of the ANN method was evaluated by comparison with the ground-based survey data. The dose rate map created by the ANNs method reproduced ground-based survey results better than traditional methods.

Translation and Psychometric Analysis of the Japanese Version of the Perceived Maternal Parenting Self-Efficacy Scale.

OBJECTIVE: To translate the Perceived Maternal Parenting Self-Efficacy (PMP S-E) scale to Japanese and test its psychometric properties among Japanese mothers of low-birth-weight (LBW) infants. DESIGN: Descriptive psychometric study. SETTING: NICUs in two regional perinatal care centers in the Kinki region of Japan. PARTICIPANTS: Seventy-nine Japanese mothers of LBW infants hospitalized in NICUs. METHODS: First, we translated the PMP S-E scale into Japanese and assessed its face and content validity. Second, we assessed the internal consistency, test-retest reliability, and criterion-related and construct validity of the Japanese version of the PMP S-E (JPMP S-E) with data from Japanese mothers of LBW infants. RESULTS: The JPMP S-E mean score was 53.0 (SD = 7.1); the total scores ranged from 38 to 68. The intraclass correlation coefficient of test-retest reliability was .75, and Cronbach's alpha coefficient was .90. With regard to criterion-related validity, we found a significant positive correlation between the JPMP S-E and the Maternal Attachment Inventory Japanese version (r = .45, p < .001), but no correlation existed between the JPMP S-E and the General Self-Efficacy Scale (r = .21, p = .06). We evaluated construct validity using confirmatory factor analysis to assess whether the model fit the previously determined structure of the PMP S-E. The model fit was moderate in the confirmatory factor analysis (comparative fit index = .63, goodness-of-fit index = .63, root mean square error of approximation = .15). CONCLUSION: We found adequate estimates of reliability and moderate indicators of validity for the JPMP S-E, which support the use of the tool for clinical and research purposes.

Development of Band-shaped Device and Detection Algorithm of Laryngeal Elevation.

This study concerns a measurement device and an algorithm of the laryngeal elevation for the Mendelsohn maneuver. The measurement device is band-shaped and measures the change of the circumferential length of the neck by stretchable strain sensors. The device is lightweight of 35 g. The algorithm detects the onset and offset points in time of the laryngeal elevation by the first-order difference and the dynamic time warping distance. Twelve elderly people participated in an experiment to validate the effectiveness of the device. A clustering method separated the measurement data into two groups based on their waveforms. We defined template data from the measurement data. The algorithm detected the onset and offset time by using the template data. Although the offset time of a group had an error of about 4 s, the onset and offset time points of the other group were errors within 1 s.

Measurement of laryngeal elevation time using a flexible surface stretch sensor.

BACKGROUND: Dysphagia is a growing health problem in aging societies. An observational cohort study targeting community-dwelling populations revealed that 16% of elderly subjects present with dysphagia. There is a need in elderly communities for systematic dysphagia assessment. OBJECTIVE: This study aimed to verify whether laryngeal elevation in the pharyngeal phase could be measured from the body surface using thin and flexible stretch sensors. METHODS: Thirty-two elderly subjects (17 males, 15 females; mean age ± SD: 89.2 ± 6.2 years) with suspected dysphagia underwent a swallowing contrast examination in which seven stretch sensors were attached to the front of the neck. The elongation of the sensors was measured and compared to the laryngeal elevation time values obtained using videofluorography. The sensor signal detected the laryngeal elevation start time, conclusion of the descent of the larynx, and the laryngeal elevation time. The respective laryngeal elevation times obtained using videofluorography and using the sensor were compared using the Bland-Altman method. RESULTS: The laryngeal elevation time was 1.34 ± 0.46 s with the stretch sensor and 1.49 ± 0.56 s with videofluorography. There was a significant positive correlation between the duration obtained by both methods (r = .69, P < .0001). A negative additional significant bias of -0.15 s (95% confidence interval -0.30 to -0.03, P = .046) was noted in the laryngeal elevation time from the videofluorography measurement. CONCLUSION: Laryngeal elevation time can be measured non-invasively from the neck surface using stretch sensors.