Publications by authors named "Junji Watanabe"

171 Publications

Cryoballoon ablation for atrial fibrillation without the use of a contrast medium: a combination of the intracardiac echocardiography and pressure wave monitoring guided approach.

Heart Vessels 2021 Oct 12. Epub 2021 Oct 12.

Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan.

In cryoballoon ablation (CBA), a contrast medium is commonly used to confirm balloon occlusion of the pulmonary veins (PVs). However, a contrast medium cannot always be used in patients with renal dysfunction and allergy. The present study aimed to assess the efficacy and safety of CBA without the use of a contrast medium. We retrospectively examined consecutive patients with paroxysmal atrial fibrillation (PAF) who underwent first-time CBA. We compared the procedural results and outcomes in patients for whom a contrast medium was used (contrast group) and those from whom a contrast medium was not used (non-contrast group). In the non-contrast group, we used saline injection on the intracardiac echocardiography and pressure wave monitoring for PV occlusion. Fifty patients (200 PVs) and 22 patients (88 PVs) underwent CBA with and without a contrast medium, respectively. The success rate of PV isolation with CBA alone was 93% and 90% in the non-contrast and contrast groups, respectively (p = 0.40). The fluoroscopy time and nadir temperature were significantly lower in the non-contrast group as compared to that in the contrast group. The recurrence rate 1 year after ablation did not differ between the two groups (18% vs. 18%, p > 0.99). Furthermore, the number of reconnected PVs in patients with recurrence was significantly lower in the non-contrast group than in the contrast group (6% vs. 36%, p = 0.017). In conclusion, CBA using the intracardiac echocardiography and pressure monitoring approach without the use of a contrast medium was safe and efficient.
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http://dx.doi.org/10.1007/s00380-021-01963-3DOI Listing
October 2021

Social Isolation Induces Neuroinflammation And Microglia Overactivation, While Dihydromyricetin Prevents And Improves Them.

Res Sq 2021 Oct 1. Epub 2021 Oct 1.

Anxiety disorders are the most prevalent mental illnesses in the U.S. and are estimated to consume one-third of the country's mental health treatment cost. Although anxiolytic therapies are available, many patients still exhibit treatment-resistance, relapse, or substantial side effects. Further, due to the COVID-19 pandemic and stay-at-home order, social isolation, fear of the pandemic, and unprecedented times, the incidence of anxiety has dramatically increased. Previously, we have demonstrated dihydromyricetin (DHM), the major bioactive flavonoid extracted from , exhibits anxiolytic properties in a mouse model of social isolation-induced anxiety. Because GABAergic transmission modulates the immune system in addition to the inhibitory signal transmission, we investigated the effects of short-term social isolation on the neuroimmune system. Eight-week-old male C57BL/6 mice were housed under absolute social isolation for 4 weeks. The anxiety like behaviors after DHM treatment were examined using elevated plus maze and open field behavioral tests. Gephyrin protein expression, microglial profile changes, NF-κB pathway activation, cytokine level, and serum corticosterone were measured. Socially isolated mice showed increased anxiety levels, reduced exploratory behaviors, and reduced gephyrin levels. Also, a dynamic alteration in hippocampal microglia were detected illustrated as a decline in microglia number and overactivation as determined by significant morphological changes including decreases in lacunarity, perimeter, and cell size and increase in cell density. Moreover, social isolation also induced an increase in serum corticosterone level and activation in NF-κB pathway. Notably, DHM treatment counteracted these changes. The results suggest that social isolation contributes to neuroinflammation, while DHM has the ability to restore neuroinflammatory changes induced by anxiety.
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http://dx.doi.org/10.21203/rs.3.rs-923871/v1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8491854PMC
October 2021

Earliest pulmonary vein potential-guided cryoballoon ablation is associated with better clinical outcomes than conventional cryoballoon ablation: A result from two randomized clinical studies.

J Cardiovasc Electrophysiol 2021 Sep 17. Epub 2021 Sep 17.

Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan.

Introduction: With regard to short-term outcome in atrial fibrillation (AF), the benefit of cryoballoon ablation (CBA) by pressing a balloon against the earliest pulmonary vein (PV) potential site during PV isolation (earliest potential [EP]-guided CBA) has been previously demonstrated. The present study aimed to evaluate the long-term outcome of the EP-guided CBA.

Methods And Results: This study included 136 patients from two randomized studies, who underwent CBA for paroxysmal AF for the first time. Patients were randomly assigned to the EP-guided and conventional CBA groups in each study. In the EP-guided CBA group, we pressed a balloon against the EP site when the time-to-isolation (TTI) after cryoapplication exceeded 60 and 45 s in the first and second studies, respectively. We compared the clinical outcomes for 1 year after the procedure between the EP-guided CBA group (68 patients) and the conventional CBA group (68 patients). The primary endpoint was the recurrence of atrial arrhythmia after ablation. No significant differences in baseline characteristics were observed between the two groups. Compared with the conventional CBA group, the EP-guided CBA group had a significantly higher success rate at TTI ≤ 90 s (98.5% vs. 90.0%, p < .001); lower touch-up rate and total cryoapplication; and shorter procedure time, and fluoroscopy time. The recurrence at 1 year after ablation was significantly lower in the EP-guided CBA group than in the conventional CBA group (6.0% vs. 19.4%; p = .019).

Conclusions: The EP-guided CBA approach can facilitate the ablation procedure and achieve low recurrence at 1 year after ablation.
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http://dx.doi.org/10.1111/jce.15246DOI Listing
September 2021

Site-specific antibody-drug conjugates with variable drug-to-antibody-ratios for AML therapy.

J Control Release 2021 Aug 29;336:433-442. Epub 2021 Jun 29.

Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90089, USA; Department of Chemistry, Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, CA 90089, USA; Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, USA; Research Center for Liver Diseases, University of Southern California, Los Angeles, CA 90089, USA. Electronic address:

Random conjugations of chemotherapeutics to monoclonal antibodies result in heterogeneous antibody-drug conjugates (ADCs) with suboptimal pharmacological properties. We recently developed a new technology for facile generation of homogeneous ADCs by harnessing human CD38 catalytic domain and its dinucleotide-derived covalent inhibitor, termed ADP-ribosyl cyclase-enabled ADCs (ARC-ADCs). Herein we advance this technology by designing and synthesizing ARC-ADCs with customizable drug-to-antibody ratios (DARs). Through varying numbers and locations of CD38 fused to an antibody targeting human C-type lectin-like molecule-1 (hCLL-1), ARC-ADCs featuring DARs of 2 and 4 were rapidly generated via a single step with cytotoxic monomethyl auristatin F (MMAF) as payloads. In contrast to anti-hCLL-1 ARC-ADC carrying 2 drug molecules, anti-hCLL-1 ARC-ADC with a DAR of 4 shows highly potent activity in killing hCLL-1-positive acute myeloid leukemia (AML) cells both in vitro and in vivo. This work provides novel ADC candidates for combating AML and supports ARC-ADC as a general and versatile approach for producing site-specific ADCs with defined DARs.
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http://dx.doi.org/10.1016/j.jconrel.2021.06.041DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8373670PMC
August 2021

Interpersonal physiological synchrony is associated with first person and third person subjective assessments of excitement during cooperative joint tasks.

Sci Rep 2021 06 15;11(1):12543. Epub 2021 Jun 15.

NTT Communication Science Laboratories, NTT Corporation, Atsugi, Japan.

Interpersonal physiological synchrony has been shown to play important roles in social activities. While most studies have shed light on the effects of physiological synchrony on recognition of the group state, such as cohesion or togetherness, the effect of physiological synchrony on the recognition of emotional experience has not been adequately researched. In this study, we examined how physiological synchrony is associated with first- and third-person emotion recognition during a joint task. Two participants played a cooperative block-stacking game (Jenga), alternating their roles as player and adviser, while their heart rates were recorded. The participants evaluated their own emotional experience for each turn. Bystanders watched the game to evaluate the players' emotions. Results showed that the players' subjective excitement increased not only with their own heart rate, but also with increased heart rate synchrony with their adviser. Heart rate synchrony between player and adviser also related to increased intensity in perceived excitement from the bystanders. Given that both first- and third-person emotion recognition can have cumulative impacts on a group, the relationship between physiological synchrony and emotion recognition observed in the present study will help deepen understanding of the psychophysiological mechanisms underlying larger group phenomena such as crowd excitement.
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http://dx.doi.org/10.1038/s41598-021-91831-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8206359PMC
June 2021

Automatic Estimation of Multidimensional Personality From a Single Sound-Symbolic Word.

Front Psychol 2021 22;12:595986. Epub 2021 Apr 22.

Department of Informatics, The University of Electro-Communications, Chofu, Japan.

Researchers typically use the "big five" traits (Extroversion, Agreeableness, Conscientiousness, Neuroticism, and Openness) as a standard way to describe personality. Evaluation of personality is generally conducted using self-report questionnaires that require participants to respond to a large number of test items. To minimize the burden on participants, this paper proposes an alternative method of estimating multidimensional personality traits from only a single word. We constructed a system that can convert a sound-symbolic word (SSW) that intuitively expresses personality traits into information expressed by 50 personality-related adjective pairs. This system can obtain information equivalent to the adjective scales using only a single word instead of asking many direct questions. To achieve this, we focused on SSWs in Japanese that have the association between linguistic sounds and meanings and express diverse and complex aspects of personality traits. We evaluated the prediction accuracy of the system and found that the multiple correlation coefficients for 48 personality-related adjective pairs exceeded 0.75, indicating that the model could explain more than half of the variations in the data. In addition, we conducted an evaluation experiment in which participants rated the appropriateness of the system output using a seven-point scale (with -3 as absolutely inappropriate and +3 as completely appropriate). The average score for 50 personality-related adjective pairs was 1.25. Thus, we believe that this system can contribute to the field of personality computing, particularly in terms of personality evaluation and communication.
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http://dx.doi.org/10.3389/fpsyg.2021.595986DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8102050PMC
April 2021

Disappearance pattern and the last remaining earliest pulmonary vein potential during cryoballoon ablation in predicting recurrence and conduction gap site of pulmonary veins.

Heart Vessels 2021 Aug 26;36(8):1190-1200. Epub 2021 Jan 26.

Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan.

Electrophysiological studies have rarely evaluated the sites prone to pulmonary vein (PV) conduction gap during cryoballoon ablation (CBA) for atrial fibrillation (AF). In addition, no studies have analyzed the sequence of PV potentials just before PV isolation during CBA for AF. Of the 238 patients who underwent first-time CBA for paroxysmal AF, 115 PVs of 29 patients who underwent repeat session due to recurrence after the procedure were retrospectively evaluated in the study. We evaluated the disappearance pattern of PV potential and PV reconnection on intracardiac electrograms and investigated whether the conduction gap site of the PV was related to the last remaining earliest PV potential (EP) and sequence pattern during the first-time CBA. Time to isolation was observed in 81 PVs during the first-time CBA. At the repeat session, PV reconnection was only observed in 22 of 81 PVs. PV potentials disappeared with sequence changes in 36 PVs and without sequence changes in 38 PVs. Multivariate analysis demonstrated that disappearance of PV potentials without change in the EP site but with delay or disappearance of other PV potentials was independently associated with PV reconnection (12/22 PVs [55%] vs. 4/59 PVs [6.8%]; odds ratio 14.4; 95% confidence interval 3.75-55.5; p < 0.001). In 19 of 22 (86%) reconnected PVs, PV conduction gap sites at repeat ablation corresponded with the last remaining EP sites during first-time CBA. In conclusion, disappearance pattern of the PV potential and the last remaining EP during the CBA can predict PV reconnection and gap site.
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http://dx.doi.org/10.1007/s00380-021-01785-3DOI Listing
August 2021

Impact of the clinical frailty scale on clinical outcomes and bleeding events in patients with ST-segment elevation myocardial infarction.

Heart Vessels 2021 Jun 7;36(6):799-808. Epub 2021 Jan 7.

Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan.

The Clinical Frailty Scale (CFS) is a simple tool to assess patients' frailty and may help to predict adverse outcomes in elderly patients. The aim of the present study was to examine the impact of CFS on clinical outcomes and bleeding events after successful percutaneous coronary intervention (PCI) in ST-segment elevation myocardial infarction (STEMI). We enrolled 266 consecutive patients with STEMI who underwent primary PCI in between January 2015 and June 2018. Patients were categorized into two groups based on the CFS stages: CFS 1-3 and CFS ≥ 4. We collected the data and evaluated the relationship between the CFS grade and the incidence of major adverse cardiovascular events (MACE) and Bleeding Academic Research Consortium 3 or 5 bleeding events. Of these patients, CFS ≥ 4 was present in 59 (22.2%). During the follow-up, 37.3% in the CFS ≥ 4 group and 8.2% in the CFS 1-3 group experienced MACE. In Kaplan-Meier analysis, the proportion of MACE-free survival for 4 years was significantly lower in the CFS ≥ 4 group (log-rank P < 0.001). Additionally, the proportion of bleeding event-free survival was significantly lower in the CFS ≥ 4 group (log-rank P < 0.001). The CFS (per 1-grade increase) remained an independent significant predictor of MACE on multivariate Cox proportional hazard analysis [hazard ratio 1.39 (95% confidence interval: 1.08 to 1.79, P = 0.01)]. In conclusion, CFS was an independent predictor of future adverse cardiac events in patients with STEMI. Therefore, the assessment of CFS is crucial in this population.
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http://dx.doi.org/10.1007/s00380-020-01764-0DOI Listing
June 2021

"Textual Prosody" Can Change Impressions of Reading in People With Normal Hearing and Hearing Loss.

Front Psychol 2020 17;11:548619. Epub 2020 Dec 17.

Communication Science Laboratories, Nippon Telegraph and Telephone Corporation, Kanagawa, Japan.

Recently, dynamic text presentation, such as scrolling text, has been widely used. Texts are often presented at constant timing and speed in conventional dynamic text presentation. However, dynamic text presentation enables visually presented texts to indicate timing information, such as prosody, and the texts might influence the impression of reading. In this paper, we examined this possibility by focusing on the temporal features of digital text in which texts are represented sequentially and with varying speed, duration, and timing. We call this "textual prosody." We used three types of textual prosody: "Recorded," "Shuffled," and "Constant." Recorded prosody is the reproduction of a reader's reading with pauses and varying speed that simulates talking. Shuffled prosody randomly shuffles the time course of speed and pauses in the recorded type. Constant prosody has a constant presentation speed and provides no timing information. Experiment 1 examined the effect of textual prosody on people with normal hearing. Participants read dynamic text with textual prosody silently and rated their impressions of texts. The results showed that readers with normal hearing preferred recorded textual prosody and constant prosody at the optimum speed (6 letters/second). Recorded prosody was also preferred at a low presentation speed. Experiment 2 examined the characteristics of textual prosody using an articulatory suppression paradigm. The results showed that some textual prosody was stored in the articulatory loop despite it being presented visually. In Experiment 3, we examined the effect of textual prosody with readers with hearing loss. The results demonstrated that readers with hearing loss had positive impressions at relatively low presentation speeds when the recorded prosody was presented. The results of this study indicate that the temporal structure is processed regardless of whether the input is visual or auditory. Moreover, these results suggest that textual prosody can enrich reading not only in people with normal hearing but also in those with hearing loss, regardless of acoustic experiences.
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http://dx.doi.org/10.3389/fpsyg.2020.548619DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7773827PMC
December 2020

Impact of skeletal muscle mass on clinical outcomes in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement.

Cardiovasc Interv Ther 2021 Oct 31;36(4):514-522. Epub 2020 Oct 31.

Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan.

Low skeletal muscle mass is one of the components of sarcopenia. However, the prognostic impact of skeletal muscle mass on clinical outcomes in patients after transcatheter aortic valve replacement (TAVR) remains unclear. Therefore, we assessed the impact of skeletal muscle mass on future cardiovascular events in patients undergoing TAVR. We enrolled 71 consecutive patients who underwent TAVR for symptomatic severe aortic stenosis. We applied bilateral psoas muscles as an indicator of skeletal muscle mass. Psoas muscle volumes were measured from the origin of psoas at the level of the lumbar vertebrae to its insertion in the lesser trochanter on three-dimensional computed tomography datasets. Psoas muscle mass index (PMI) was calculated as psoas muscle volume/height (cm/m). According to the median value of PMIs (79.8 and 60.0 cm/m for men and women), the enrolled patients were divided into two groups. During the follow-up, 11 (31.4%) patients in low PMI group and 4 (11.1%) in high PMI group experienced major adverse cardiovascular events (MACE) defined as a composite of death from any cause, myocardial infarction, heart failure hospitalization, and stroke. The proportion of MACE-free survival was significantly lower in low PMI group (log-rank P = 0.033), mainly due to the difference of hospital readmission for congestive heart failure. On multivariate Cox proportional hazard analysis, PMI remained an independent negative predictor of MACE [hazard ratio 0.95 (95% confidence interval 0.92-0.98, P = 0.002)]. In conclusion, low skeletal muscle mass independently predicted MACE in patients undergoing TAVR.
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http://dx.doi.org/10.1007/s12928-020-00725-8DOI Listing
October 2021

CAR T-cells that target acute B-lineage leukemia irrespective of CD19 expression.

Leukemia 2021 01 24;35(1):75-89. Epub 2020 Mar 24.

Interdepartmental Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX, USA.

Chimeric antigen receptor (CAR) T-cells targeting CD19 demonstrate remarkable efficacy in treating B-lineage acute lymphoblastic leukemia (BL-ALL), yet up to 39% of treated patients relapse with CD19(-) disease. We report that CD19(-) escape is associated with downregulation, but preservation, of targetable expression of CD20 and CD22. Accordingly, we reasoned that broadening the spectrum of CD19CAR T-cells to include both CD20 and CD22 would enable them to target CD19(-) escape BL-ALL while preserving their upfront efficacy. We created a CD19/20/22-targeting CAR T-cell by coexpressing individual CAR molecules on a single T-cell using one tricistronic transgene. CD19/20/22CAR T-cells killed CD19(-) blasts from patients who relapsed after CD19CAR T-cell therapy and CRISPR/Cas9 CD19 knockout primary BL-ALL both in vitro and in an animal model, while CD19CAR T-cells were ineffective. At the subcellular level, CD19/20/22CAR T-cells formed dense immune synapses with target cells that mediated effective cytolytic complex formation, were efficient serial killers in single-cell tracking studies, and were as efficacious as CD19CAR T-cells against primary CD19(+) disease. In conclusion, independent of CD19 expression, CD19/20/22CAR T-cells could be used as salvage or front-line CAR therapy for patients with recalcitrant disease.
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http://dx.doi.org/10.1038/s41375-020-0792-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7519582PMC
January 2021

Frequency of Switching Touching Mode Reflects Tactile Preference Judgment.

Sci Rep 2020 02 20;10(1):3022. Epub 2020 Feb 20.

NTT Communication Science Laboratories, Nippon Telegraph and Telephone Corporation, 3-1, Morinosato Wakamiya Atsugi-shi, Kanagawa, 243-0198, Japan.

We can judge affective aspects of objects by actively exploring them with our hands. Previous studies have mainly focused on how the physical properties of an object's surface affect tactile preference evaluations. However, despite the widely accepted notion that the participant's strategy has a great impact on how they explore an object, there is a lack of investigations of hand motion during preference judgment and its impact on preference rating. This paper recruits the recurrence plot technique to illustrate the temporal dynamics of explorative hand motion. In an experiment, participants were asked to freely explore the surface of tactile stimuli and rate their tactile preference for them. The temporal dynamics of finger velocity and force were visualized and characterized by using recurrence quantification analysis. We found correlations between preference ratings and recurrence features that represent the temporal dynamics of explorative hand motion, in addition to correlations between preference ratings and conventional time-averaged features (e.g., averaged finger velocity). One unique feature that correlated with preference ratings was TREND, which represents to what extent similar motion patterns repeatedly occur. The results of a subsidiary analysis supported the possibility that the TREND difference can be interpreted as the frequency of switching touching modes (e.g., stroking and pushing motions). Taken together, these results suggest that participants tend to perform the same hand motion repeatedly for preferable objects, while they tend to combine different touching modes for less preferable objects. They also indicate that the recurrence plot scheme is a promising way to extract humans' strategies for tactile exploration.
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http://dx.doi.org/10.1038/s41598-020-59883-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7033153PMC
February 2020

Controlled emotional tactile stimulation during functional magnetic resonance imaging and electroencephalography.

J Neurosci Methods 2019 11 12;327:108393. Epub 2019 Aug 12.

Center of KANSEI Innovation, Hiroshima University, Hiroshima, Japan.

Background: Tactile stimulation used to induce emotional responses is often not well-controlled. Replicating the same tactile stimulations across studies is difficult, compared to replicating visual and auditory modalities, which have standardized stimulus sets. Standardizing a stimulation method by replicating stimuli across studies is necessary to further elucidate emotional responses in neuroscience research using tactile stimulation.

The New Method: We developed a tactile stimulation device. The device's ultrasonic motor and optical force sensor have the following criteria: (1) controls the physical property of stimuli, pressure, and stroking speed; (2) measures actual touch timing; (3) is safe to use in a magnetic resonance imaging (MRI) scanner; and (4) produces low noise in electroencephalography (EEG) and MRI.

Results: The noise level of the device's drive was sufficiently low. For the EEG experiment, we successfully used signal processing to diminish the commercial power supply noise. For functional MRI (fMRI) scans, we found <5% signal loss occurred during device rotation.

Comparison With Existing Method(s): We found no previous report about the noise level of a tactile stimulation device used to induce emotional responses during EEG and fMRI recordings. The signal loss rate was comparable with that of other robotic devices used in MRI scanners. Emotional feelings induced by this stimulation method were comparable with those elicited in other sensory modalities.

Conclusions: The developed device could be used for cognitive-affective neuroscience research when conducting EEG and fMRI scans. The device should aid in standardizing affective tactile stimulation for research in psychology and cognitive neuroscience.
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http://dx.doi.org/10.1016/j.jneumeth.2019.108393DOI Listing
November 2019

Earliest pulmonary vein potential-guided cryoballoon ablation for atrial fibrillation.

Heart Vessels 2020 Feb 11;35(2):232-238. Epub 2019 Jul 11.

Department of Cardiology, Nagoya University Hospital, Nagoya, Japan.

No studies have evaluated both the time-to-isolation (TTI) and the sequence of pulmonary vein (PV) potentials in cryoballoon ablation (CBA) for atrial fibrillation (AF). This study aimed to prospectively evaluate the acute results of pulmonary vein isolation (PVI) using a novel CBA technique-the earliest potential (EP) of PV-guided CBA-in paroxysmal AF. We pressed a balloon against the earliest PV potential site during PVI when TTI could not be achieved within 60 s (EP-guided CBA group). We compared 32 patients consecutively treated by EP-guided CBA to 32 patients treated without pressing the balloon against the EP site (conventional CBA group). The cryoapplication protocol was the same, except with regard to the pressing of the balloon. All 256 PVs (EP-guided CBA group, 128 PVs; conventional CBA group, 128 PVs) were isolated successfully. The TTI observation rate was similar in both groups. Compared with conventional CBA, EP-guided CBA was associated with a lower non-success rate of TTI ≤ 90 s (9% vs. 26%; P = 0.040) and shorter left atrial dwell time (38 ± 9 vs. 46 ± 19 min; P = 0.036), total procedure time (76 ± 15 vs. 87 ± 23 min; P = 0.043), and fluoroscopy time (23 ± 8 vs. 30 ± 11 min; P = 0.006). This novel EP-guided CBA approach may help facilitate the ablation procedure.
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http://dx.doi.org/10.1007/s00380-019-01471-5DOI Listing
February 2020

Visualizing Individual Perceptual Differences Using Intuitive Word-Based Input.

Front Psychol 2019 21;10:1108. Epub 2019 May 21.

NTT Communication Science Laboratories, Nippon Telegraph and Telephone Corporation, Kanagawa, Japan.

Numerous studies have investigated the fundamental dimensions of human tactile perceptual space using a wide range of materials. Participants generally touch materials and quantitatively evaluate variations in tactile sensations for pairs of adjectives pertaining to the material properties, such as smooth-rough and soft-hard. Thus, observers evaluate their perceptual experiences one by one in terms of adjective pairs. We previously proposed an alternative method of qualitative evaluation of tactile sensations. Our system can automatically estimate ratings of fundamental tactile properties from single sound-symbolic words. We were able to construct a word-based perceptual space by collecting words that express tactile sensations and applying them to the system. However, to explore individual differences in perceptual spaces, different databases for converting words into ratings of adjective pairs are required for each individual. To address this, in the present study we created an application that can automatically generate an individualized perceptual space by moving only a few words in the initial word-based perceptual space. In addition, we evaluated the efficacy of the application by comparing the tactile perceptual space before and after use.
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http://dx.doi.org/10.3389/fpsyg.2019.01108DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6536641PMC
May 2019

Estimating Tactile Perception by Observing Explorative Hand Motion of Others.

IEEE Trans Haptics 2018 Apr-Jun;11(2):192-203

When we acquire tactile information about an object's surface, we actively move our hands. Past studies have shown a correlation between participants' (i.e., touchers') hand motion in tactile exploration and the evaluated tactile attributes of the object, which suggests that tactile perception can be estimated from statistical analysis of touchers' hand motion. Though it has been reported that the statistical analysis of hand motion can indeed estimate tactile perception, whether humans can estimate tactile perception by observing the hand motion of others remains unclear. To investigate this, we conducted experiments wherein observers watched point-light moving hands of touchers in tactile exploration and evaluated the material being touched. Our results show that, although observers' estimation of touchers' perception was not accurate, observers extracted information from touchers' hand motion for estimation, and the correlations within observers' estimation were high. These results suggest that human observers can estimate tactile perception through visual observation of the hand motion of others by adopting common strategies about the relationships between touchers' hand motion and tactile perception.
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http://dx.doi.org/10.1109/TOH.2017.2775631DOI Listing
January 2019

Bouba/Kiki in Touch: Associations Between Tactile Perceptual Qualities and Japanese Phonemes.

Front Psychol 2018 12;9:295. Epub 2018 Mar 12.

NTT Communication Science Laboratories, Nippon Telegraph and Telephone Corporation, Kanagawa, Japan.

Several studies have shown cross-modal associations between sounds and vision or gustation by asking participants to match pre-defined sound-symbolic words (SSWs), such as "bouba" or "kiki," with visual or gustatory materials. Here, we conducted an explorative study on cross-modal associations of tactile sensations using spontaneous production of Japanese SSWs and semantic ratings. The Japanese language was selected, because it has a large number of SSWs that can represent a wide range of tactile perceptual spaces with fine resolution, and it shows strong associations between sound and touch. In the experiment, we used 120 everyday materials to cover basic material categories that could be associated with fundamental dimensions of tactile perception. Upon contact with these materials, participants expressed their tactile sensations by using Japanese SSWs, and at the same time, evaluated the tactile sensations by semantic differential scales using adjective pairs. Thanks to the variety of testing materials, we were able to demonstrate the existence of systematic associations between sounds and tactile fundamental perceptual dimensions in a more detailed and comprehensive way than ever done so before. In particular, we found that for vowels, positive tactile ratings were associated with the back vowel (/u/), while negative ratings were associated with the front vowels (/i/ and /e/). The central vowels (/o/ and /a/) were mainly associated with rough, hard, and dry feelings. Consonants were categorized based on vocal features and articulation. The category of the voiced consonants (e.g., /dz/ and /g/) corresponded to feelings of roughness, while that of voiceless consonants (e.g., /ʦ/, and /s/) corresponded to feelings of smoothness. The categories of the bilabial plosive (/p/ and /b/) and voiced alveolar nasal (/n/) consonants were mainly related to soft, sticky and wet feelings, while that of voiceless alveolar affricate (/ʦ/) and voiceless velar plosive (/k/) consonants were related to hard, slippery and dry feelings.
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http://dx.doi.org/10.3389/fpsyg.2018.00295DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5857596PMC
March 2018

Perceptual-Semantic Congruency Facilitates Semantic Discrimination of Thermal Qualities.

Front Psychol 2017 6;8:2113. Epub 2017 Dec 6.

Department of Information and Communications Engineering, Tokyo Institute of Technology, Tokyo, Japan.

The ability to sense temperature is vital to our life. It signals the environmental condition, reflects the physiological conditions of our own body, and generates feelings of pleasantness or unpleasantness. Moreover, recent studies have demonstrated implicit associations between physical temperature and social/emotional concepts, suggesting the processing of temperature may even influence cognition. In this work, we examined the effect of physical warmth and coldness on semantic cognition. Participants performed speeded target categorization for thermal descriptors in the form of semantic words or illustrative figures representing the thermal qualities "warm" or "cold" while physical thermal stimulation was presented. We compared the average reaction time (RT) for the congruent and incongruent conditions managed by response key assignments. In the congruent condition, the response key for the symbol associated with warmth (coldness) was assigned to the hand with warm (cold) thermal stimulation, and in the incongruent condition the key assignment was reversed. Our results demonstrate that the average RT in the congruent condition was faster than in the incongruent one for both forms of thermal descriptors, suggesting that the experience of physical temperature facilitates the internal processing of the meaning of thermal quality.
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http://dx.doi.org/10.3389/fpsyg.2017.02113DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5724365PMC
December 2017

Impact of Coronary Stent Fracture on Restenotic Neointimal Tissue Characterization After Drug-Eluting Stent Implantation.

Int Heart J 2017 Dec 17;58(6):861-867. Epub 2017 Nov 17.

Department of Cardiology, Nagoya University Graduate School of Medicine.

Although drug-eluting stents (DESs) reduce the rates of in-stent restenosis (ISR) and subsequent target lesion revascularization, stent fracture (SF) after DES implantation has become an important concern because of its potential association with restenosis and stent thrombosis. We aimed to assess the pathogenic impact of SF on in-stent restenotic neointimal tissue components after DES implantation. We analyzed 43 consecutive patients (14 with SF and 29 without SF) with ISR requiring revascularization after DES implantation between January 2008 and March 2014. For evaluation of in-stent tissue components, integrated backscatter intravascular ultrasound (IB-IVUS) was performed. SF was defined as complete or partial separation of stent segments observed using plain fluoroscopy or intravascular ultrasound. On volumetric IB-IVUS analyses, patients with SF had a significantly higher percentage of lipid tissue volume within the neointima and a significantly lower percentage of fibrous tissue volume than those without (37.3 ± 18.9% versus 24.9 ± 12.4%, P = 0.02, and 61.2 ± 18.3 versus 72.6 ± 12.1%, P = 0.04, respectively). Moreover, SF was positively correlated with the percentage of lipid volume on multiple linear regression analysis after adjustment for confounding factors (β = 0.36, P = 0.03). The interval from stent implantation was similar in both groups (47.0 ± 28.7 versus 37.7 ± 33.3 months; P = 0.39). In conclusion, SF is associated with larger lipid tissue volume within the neointima after DES placement, suggesting a contribution to the development of neoatherosclerosis and vulnerable neointima. Thus SF might lead to future adverse coronary events.
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http://dx.doi.org/10.1536/ihj.16-571DOI Listing
December 2017

Reading Traits for Dynamically Presented Texts: Comparison of the Optimum Reading Rates of Dynamic Text Presentation and the Reading Rates of Static Text Presentation.

Front Psychol 2017 17;8:1390. Epub 2017 Aug 17.

Human Information Science Laboratory, Communication Science Laboratories, Nippon Telegraph and Telephone CorporationKanagawa, Japan.

With the growth in digital display technologies, dynamic text presentation is used widely in every day life, such as in electric advertisements and tickers on TV programs. Unlike static text reading, little is known about the basic characteristics underlying reading dynamically presented texts. Two experiments were performed to investigate this. Experiment 1 examined the optimum rate of dynamic text presentation in terms of a readability and favorability. This experiment demonstrated that, when the rate of text presentation was changed, there was an optimum presentation rate (around 6 letters/s in our condition) regardless of difficulty level. This indicates that the presentation rate of dynamic texts can affect the impression of reading. In Experiment 2, to elucidate the traits underlying dynamic text reading, we measured the reading speeds of silent and trace reading among the same participants and compared them with the optimum presentation rate obtained in Experiment 1. The results showed that the optimum rate was slower than with silent reading and faster than with trace reading, and, interestingly, the individual optimum rates of dynamic text presentation were correlated with the speeds of both silent and trace reading. In other words, the readers who preferred a fast rate in dynamic text presentation would also have a high reading speed for silent and trace reading.
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http://dx.doi.org/10.3389/fpsyg.2017.01390DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5562726PMC
August 2017

Sub-Second Temporal Integration of Vibro-Tactile Stimuli: Intervals between Adjacent, Weak, and Within-Channel Stimuli Are Underestimated.

Front Psychol 2017 31;8:1295. Epub 2017 Jul 31.

NTT Communication Science Laboratories, Nippon Telegraph and Telephone CorporationKanagawa, Japan.

Tactile estimation of sub-second time is essential for correct recognition of sensory inputs and dexterous manipulation of objects. Despite our intuitive understanding that time is robustly estimated in any situation, tactile sub-second time is altered by, for example, body movement, similar to how visual time is modulated by eye movement. The effects of simpler factors, such as stimulus location, intensity, and frequency, have also been reported in temporal tasks in other modalities, but their effects on tactile sub-second interval estimation remain obscure. Here, we were interested in whether a perceived short interval presented by tactile stimuli is altered only by changing stimulus features. The perceived interval between a pair of stimuli presented on the same finger apparently became short relative to that on different fingers; that of a weak-intensity pair relative to that of a pair with stronger intensity was decreased; and that of a pair with the same frequency relative to one with different frequencies was underestimated. These findings can be ascribed to errors in encoding temporal relationships: nearby-space/weak-intensity/similar-frequency stimuli presented within a short time difference are likely to be integrated into a single event and lead to relative time compression.
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http://dx.doi.org/10.3389/fpsyg.2017.01295DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5534472PMC
July 2017

Integration of vibrotactile frequency information beyond the mechanoreceptor channel and somatotopy.

Sci Rep 2017 06 5;7(1):2758. Epub 2017 Jun 5.

NTT Communication Science Laboratories, NTT Corporation, Kanagawa, Japan.

A wide variety of tactile sensations arise from the activation of several types of mechanoreceptor-afferent channels scattered all over the body, and their projections create a somatotopic map in the somatosensory cortex. Recent findings challenge the traditional view that tactile signals from different mechanoreceptor-channels/locations are independently processed in the brain, though the contribution of signal integration to perception remains obscure. Here we show that vibrotactile frequency perception is functionally enriched by signal integration across different mechanoreceptor channels and separate skin locations. When participants touched two sinusoidal vibrations of far-different frequency, which dominantly activated separate channels with the neighboring fingers or the different hand and judged the frequency of one vibration, the perceived frequency shifted toward the other (assimilation effect). Furthermore, when the participants judged the frequency of the pair as a whole, they consistently reported an intensity-based interpolation of the two vibrations (averaging effect). Both effects were similar in magnitude between the same and different hand conditions and significantly diminished by asynchronous presentation of the vibration pair. These findings indicate that human tactile processing is global and flexible in that it can estimate the ensemble property of a large-scale tactile event sensed by various receptors distributed over the body.
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http://dx.doi.org/10.1038/s41598-017-02922-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5459808PMC
June 2017

Exploring Tactile Perceptual Dimensions Using Materials Associated with Sensory Vocabulary.

Front Psychol 2017 13;8:569. Epub 2017 Apr 13.

NTT Communication Science Laboratories, Nippon Telegraph and Telephone CorporationKanagawa, Japan.

Considering tactile sensation when designing products is important because the decision to purchase often depends on how products feel. Numerous psychophysical studies have attempted to identify important factors that describe tactile perceptions. However, the numbers and types of major tactile dimensions reported in previous studies have varied because of differences in materials used across experiments. To obtain a more complete picture of perceptual space with regard to touch, our study focuses on using vocabulary that expresses tactile sensations as a guiding principle for collecting material samples because these types of words are expected to cover all the basic categories within tactile perceptual space. We collected 120 materials based on a variety of Japanese sound-symbolic words for tactile sensations, and used the materials to examine tactile perceptual dimensions and their associations with affective evaluations. Analysis revealed six major dimensions: "Affective evaluation and Friction," "Compliance," "Surface," "Volume," "Temperature," and "Naturalness." These dimensions include four factors that previous studies have regarded as fundamental, as well as two new factors: "Volume" and "Naturalness." Additionally, we showed that "Affective evaluation" is more closely related to the "Friction" component (slipperiness and dryness) than to other tactile perceptual features. Our study demonstrates that using vocabulary could be an effective method for selecting material samples to explore tactile perceptual space.
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http://dx.doi.org/10.3389/fpsyg.2017.00569DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5390040PMC
April 2017

Dual Electrophoresis Detection System for Rapid and Sensitive Immunoassays with Nanoparticle Signal Amplification.

Sci Rep 2017 02 15;7:42562. Epub 2017 Feb 15.

Beijing Key Laboratory of Bioprocess, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing Laboratory of Biomedical Materials, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, P. R. China.

An electrophoretic technique was combined with an enzyme-linked immunosorbent assay (ELISA) system to achieve a rapid and sensitive immunoassay. A cellulose acetate filter modified with polyelectrolyte multilayer (PEM) was used as a solid substrate for three-dimensional antigen-antibody reactions. A dual electrophoresis process was used to induce directional migration and local condensation of antigens and antibodies at the solid substrate, avoiding the long diffusion times associated with antigen-antibody reactions in conventional ELISAs. The electrophoretic forces drove two steps in the ELISA process, namely the adsorption of antigen, and secondary antibody-labelled polystyrene nanoparticles (NP-Ab). The total time needed for dual electrophoresis-driven detection was just 4 min, nearly 2 h faster than a conventional ELISA system. Moreover, the rapid NP-Ab electrophoresis system simultaneously achieved amplification of the specific signal and a reduction in noise, leading to a more sensitive NP-Ab immunoassay with a limit of detection (LOD) of 130 fM, and wide range of detectable concentrations from 0.13 to 130 pM. These results suggest that the combination of dual electrophoresis detection and NP-Ab signal amplification has great potential for future immunoassay systems.
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http://dx.doi.org/10.1038/srep42562DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5309740PMC
February 2017

Hydrophilic Polyelectrolyte Multilayers Improve the ELISA System: Antibody Enrichment and Blocking Free.

Polymers (Basel) 2017 Feb 12;9(2). Epub 2017 Feb 12.

Beijing Key Laboratory of Bioprocess, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing Laboratory of Biomedical Materials, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China.

In this study, polyelectrolyte multilayers were fabricated on a polystyrene (PS) plate using a Layer-by-Layer (LbL) self-assembly technique. The resulting functional platform showed improved performance compared with conventional enzyme-linked immunosorbent assay (ELISA) systems. Poly(diallyldimethylammonium chloride) (PDDA) and poly(acrylic acid) (PAA) were used as cationic and anionic polyelectrolytes. On the negatively-charged (PDDA/PAA)₃ polyelectrolyte multilayers the hydrophilic PAA surface could efficiently decrease the magnitude of the noise signal, by inhibiting nonspecific adsorption even without blocking reagent adsorption. Moreover, the (PDDA/PAA)₃ substrate covalently immobilized the primary antibody, greatly increasing the amount of primary antibody adsorption and enhancing the specific detection signal compared with a conventional PS plate. The calibration curve of the (PDDA/PAA)₃ substrate showed a wide linear range, for concentrations from 0.033 to 33 nM, a large specific signal change, and a detection limit of 33 pM, even though the conventional blocking reagent adsorption step was omitted. The (PDDA/PAA)₃ substrate provided a high-performance ELISA system with a simple fabrication process and high sensitivity; the system presented here shows potential for a variety of immunosensor applications.
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http://dx.doi.org/10.3390/polym9020051DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6432497PMC
February 2017

Automatic Estimation of Multidimensional Ratings from a Single Sound-Symbolic Word and Word-Based Visualization of Tactile Perceptual Space.

IEEE Trans Haptics 2017 Apr-Jun;10(2):173-182. Epub 2016 Oct 14.

Several pairs of Japanese adjective words pertaining to material's properties, such as roughness and hardness, have been used in Japanese studies to quantitatively evaluate variations in tactile sensations. This method asks observers to analyze their perceptual experiences one by one. An alternative notion is that human perceptual recognition is performed as a whole rather than by using fragmented factors. Based on this notion, we propose a system that can automatically estimate multidimensional ratings of touch from a single sound-symbolic word that has been spontaneously and intuitively expressed by a user. When a user inputs a sound-symbolic word into the system, the system refers to a database of phonemes and their auditory impressions, and calculates ratings in terms of 26 pairs of fundamental scales of touch. The estimated ratings of sound-symbolic words enable us to visualize a tactile perceptual space. Our study provides an alternative method for estimating the fine quality of tactile sensations.
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http://dx.doi.org/10.1109/TOH.2016.2615923DOI Listing
May 2018

Sanshool on The Fingertip Interferes with Vibration Detection in a Rapidly-Adapting (RA) Tactile Channel.

PLoS One 2016 9;11(12):e0165842. Epub 2016 Dec 9.

NTT Communication Science Laboratories, NTT Corporation, Kanagawa, Japan.

An Asian spice, Szechuan pepper (sanshool), is well known for the tingling sensation it induces on the mouth and on the lips. Electrophysiological studies have revealed that its active ingredient can induce firing of mechanoreceptor fibres that typically respond to mechanical vibration. Moreover, a human behavioral study has reported that the perceived frequency of sanshool-induced tingling matches with the preferred frequency range of the tactile rapidly adapting (RA) channel, suggesting the contribution of sanshool-induced RA channel firing to its unique perceptual experience. However, since the RA channel may not be the only channel activated by sanshool, there could be a possibility that the sanshool tingling percept may be caused in whole or in part by other sensory channels. Here, by using a perceptual interference paradigm, we show that the sanshool-induced RA input indeed contributes to the human tactile processing. The absolute detection thresholds for vibrotactile input were measured with and without sanshool application on the fingertip. Sanshool significantly impaired detection of vibrations at 30 Hz (RA channel dominant frequency), but did not impair detection of higher frequency vibrations at 240 Hz (Pacinian-corpuscle (PC) channel dominant frequency) or lower frequency vibrations at 1 Hz (slowly adapting 1 (SA1) channel dominant frequency). These results show that the sanshool induces a peripheral RA channel activation that is relevant for tactile perception. This anomalous activation of RA channels may contribute to the unique tingling experience of sanshool.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0165842PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5147812PMC
July 2017

Linkage between Free Exploratory Movements and Subjective Tactile Ratings.

IEEE Trans Haptics 2017 Apr-Jun;10(2):217-225. Epub 2016 Oct 28.

We actively move our hands and eyes when exploring the external world and gaining information about object's attributes. Previous studies showing that how we touch might be related to how we felt led us to consider whether we could decode observers' subjective tactile experiences only by analyzing their exploratory movements without explicitly asking how they perceived. However, in those studies, explicit judgment tasks were performed about specific tactile attributes that were prearranged by experimenters. Here, we systematically investigated whether exploratory movements can explain tactile ratings even when participants do not need to judge any tactile attributes. While measuring both hand and eye movements, we asked participants to touch materials freely without judging any specific tactile attributes (free-touch task) or to evaluate one of four tactile attributes (roughness, hardness, slipperiness, and temperature). We found that tactile ratings in the judgment tasks correlated with exploratory movements even in the free-touch task and that eye movements as well as hand movements correlated with tactile ratings. These results might open up the possibility of decoding tactile experiences by exploratory movements.
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http://dx.doi.org/10.1109/TOH.2016.2613055DOI Listing
April 2018

Design and synthesis of an amphiphilic graft hydrogel having a hydrophobic domain formed by multiple interactions.

Mater Sci Eng C Mater Biol Appl 2016 Nov 21;68:65-69. Epub 2016 May 21.

Department of Chemistry of Functional Molecules, Faculty of Science and Engineering, Konan University, 8-9-1 Okamoto, Higashinada, Kobe 658-8501, Japan. Electronic address:

A novel hydrogel having hydrophobic oligo segments and hydrophilic poly(acrylamidoglycolic acid) (PAGA) as pH responsive polymer segments was designed and synthesized to be used as a soft biomaterial. Poly(trimethylene carbonate) (PTMC) as the side chain, for which the degrees of polymerization were 9, 19, and 49, and the composition ratios were 1, 5, and 10mol%, was used as the oligo segment in the hydrogel. The swelling ratio of the hydrogel was investigated under various changes in conditions such as pH, temperature, and hydrogen bonding upon urea addition. Under pH2-11 conditions, the graft gel reversibly swelled and shrank due to the effect of PAGA main chain. The interior morphology and skin layer of the hydrogel was observed by a scanning electron microscope. The hydrogel composed of PAGA as the hydrophilic polymer backbone had a sponge-like structure, with a pore size of approximately 100μm. On the other hand, upon increasing the ratio of trimethylene carbonate (TMC) units in the hydrogel, the pores became smaller or disappeared. Moreover, thickness of the skin layer significantly increased with the swelling ratio depended on the incorporation ratios of the PTMC macromonomer. Molecular incorporation in the hydrogel was evaluated using a dye as a model drug molecule. These features would play an important role in drug loading. Increasing the ratio of TMC units favored the adsorption of the dye and activation of the incorporation behavior.
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http://dx.doi.org/10.1016/j.msec.2016.05.061DOI Listing
November 2016

Two-Dimensional Skyrmion Lattice Formation in a Nematic Liquid Crystal Consisting of Highly Bent Banana Molecules.

Angew Chem Int Ed Engl 2016 09 11;55(38):11552-6. Epub 2016 Aug 11.

Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, 2-12-1 O-okayama, Tokyo, 152-8552, Japan.

We synthesized a novel banana-shaped molecule based on a 1,7-naphthalene central core that exhibits a distinct mesomorphism of the nematic-to-nematic phase transition. Both the X-ray profile and direct imaging of atomic force microscopy (AFM) investigations clearly indicates the formation of an anomalous nematic phase possessing a two-dimensional (2D) tetragonal lattice with a large edge (ca. 59 Å) directed perpendicular to the director in the low-temperature nematic phase. One plausible model is proposed by an analogy of skyrmion lattice in which two types of cylinders formed from left- and right-handed twist-bend helices stack into a 2D tetragonal lattice, diminishing the inversion domain wall.
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http://dx.doi.org/10.1002/anie.201606388DOI Listing
September 2016
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