Reduced menthol sensitivity in a prodromal Parkinson's disease model induced by intranasal rotenone treatment

Parkinson's disease (PD) is a neurodegenerative disorder characterized by motor symptoms, and it is associated with several prodromal non-motor symptoms, including an impaired sense of smell, taste and touch. We previously reported that bitter taste impairments occur independently of olfactory impairments in an early-stage PD animal model using short-term intranasal rotenone-treated mice. Cool temperatures also affect bitter taste perception, but it remains unclear whether or not bitter taste impairments result from an altered sensitivity for intraoral cool stimuli. We examined disturbances in the intraoral menthol sensitivity, such as coolness at low concentrations of menthol, using a brief-access test. Once a day, one solution from the 7-concentration series of (-)-menthol (0-2.3 mM) or the bitter taste quinine-HCl (0.3 mM) was randomly presented 20 times for 10 s to water-deprived mice before and 1 week after rotenone treatment. The total number of licks within 20 times was significantly decreased with the presentation of 2.3 mM menthol and quinine-HCl, compared to distilled water in untreated mice, but not in rotenone-treated mice. The correlation between the licks for quinine-HCl and that for menthol was increased after rotenone treatment. In contrast, the 2-bottle choice test for 48 h clarified that menthol sensitivity was increased after rotenone treatment. Furthermore, a thermal place preference test revealed that seeking behavior toward a cold-floored room was increased in the rotenone-treated mice despite the unchanged plantar cutaneous cold sensitivity. These results suggest that taste impairments in this model mice are at least partly due to intraoral somatosensory impairments, accompanied by peripheral/central malfunction.

Automatic dental age calculation from panoramic radiographs using deep learning: a two-stage approach with object detection and image classification

BACKGROUND

Dental age is crucial for treatment planning in pediatric and orthodontic dentistry. Dental age calculation methods can be categorized into morphological, biochemical, and radiological methods. Radiological methods are commonly used because they are non-invasive and reproducible. When radiographs are available, dental age can be calculated by evaluating the developmental stage of permanent teeth and converting it into an estimated age using a table, or by measuring the length between some landmarks such as the tooth, root, or pulp, and substituting them into regression formulas. However, these methods heavily depend on manual time-consuming processes. In this study, we proposed a novel and completely automatic dental age calculation method using panoramic radiographs and deep learning techniques.

METHODS

Overall, 8,023 panoramic radiographs were used as training data for Scaled-YOLOv4 to detect dental germs and mean average precision were evaluated. In total, 18,485 single-root and 16,313 multi-root dental germ images were used as training data for EfficientNetV2 M to classify the developmental stages of detected dental germs and Top-3 accuracy was evaluated since the adjacent stages of the dental germ looks similar and the many variations of the morphological structure can be observed between developmental stages. Scaled-YOLOv4 and EfficientNetV2 M were trained using cross-validation. We evaluated a single selection, a weighted average, and an expected value to convert the probability of developmental stage classification to dental age. One hundred and fifty-seven panoramic radiographs were used to compare automatic and manual human experts' dental age calculations.

RESULTS

Dental germ detection was achieved with a mean average precision of 98.26% and dental germ classifiers for single and multi-root were achieved with a Top-3 accuracy of 98.46% and 98.36%, respectively. The mean absolute errors between the automatic and manual dental age calculations using single selection, weighted average, and expected value were 0.274, 0.261, and 0.396, respectively. The weighted average was better than the other methods and was accurate by less than one developmental stage error.

CONCLUSION

Our study demonstrates the feasibility of automatic dental age calculation using panoramic radiographs and a two-stage deep learning approach with a clinically acceptable level of accuracy.

Accuracy Evaluation of an Estimation System for Dental Treatment Sites by Using Image Recognition

In dentistry, misidentification of the treatment site may occur an adverse event with irreversible consequences. Among these, the left-right tooth error is the second most common site misidentification. In this study, we developed a treatment site estimation system using image recognition, and the accuracy rate of the left and right teeth was more than 85%. The results suggest that this system can be used to prevent the misidentification of the left and right teeth.

Effect of Push-Pull HEPA Filters on Air Age in a Dental Treatment Room

Air quality was evaluated by visualizing with CFD (Computational Fluid Dynamics) where air tends to stagnate in the dental practice space when natural ventilation and HEPA filters are used together. The results showed that natural ventilation by opening and closing windows and doors alone was not sufficient.

Panoramic Radiograph Generation and Image Reconstruction from Latent Vectors Using a Generative Adversarial Network

In this study, StyleGAN2 was trained with panoramic radiographs, and original images were projected into the latent space of StyleGAN2. The resulting latent vectors were input into StyleGAN2, and corresponding images were generated to reconstruct the original images. The original and reconstructed images were evaluated by pediatric dentists and found to be similar. Our results suggest that StyleGAN2 could be applied to the anonymization and data compression of medical images.

Oral squamous cell carcinoma diagnosis in digitized histological images using convolutional neural network

Background/purpose

Diagnostic methods of oral squamous cell carcinoma (SCC) using artificial intelligence (AI) and digital-histopathologic images have been developed. However, previous AI training methods have focused on the cellular atypia given by the training of high-magnification images, and little attention has been paid to structural atypia provided by low-power wide fields. Since oral SCC has histopathologic types with bland cytology, both cellular atypia and structural atypia must be considered as histopathologic features. This study aimed to investigate AI ability to judge oral SCC in a novel training method considering cellular and structural atypia and their suitability.

Materials and methods

We examined digitized histological whole-slide images from 90 randomly selected patients with tongue SCC who attended a dental hospital. Image patches of 1000 × 1000 pixels were cut from whole-slide images at 0.3125-, 1.25-, 5-, and 20-fold magnification, and 90,059 image patches were used for training and evaluation. These image patches were resized into 224 × 224, 384 × 384, 512 × 512, and 768 × 768 pixels, and the differences in input size were analyzed. EfficientNet B0 was utilized as the convolutional neural network model. Gradient-weighted class activation mapping (Grad-CAM) was used to elucidate its validity.

Results

The proposed method achieved a peak accuracy of 99.65% with an input size of 512 × 512 pixels. Grad-CAM suggested that AI focused on both cellular and structural atypia of SCC, and tended to focus on the region surrounding the basal layer.

Conclusion

Training AI regarding both cellular and structural atypia using various magnification images simultaneously may be suitable for the diagnosis of oral SCC.

Trends and outcomes of early rehabilitation in intensive care unit for patients with cardiovascular disease – a cohort study with propensity score-matched analysis

Background

Early rehabilitation in the intensive care unit (ICU), including early mobility therapy, is known to improve the clinical outcomes in patients with critically ill. However, the effectiveness of acute-phase cardiovascular rehabilitation (CR) during ICU treatment have not been thoroughly evaluated in patients with cardiovascular disease (CVD).

Purpose

We aimed to investigate the trends and outcomes of acute-phase CR in the ICU for patients with CVD, including in-hospital and long-term clinical outcomes.

Methods

We reviewed 1948 consecutive patients with CVD admitted to tertiary academic ICU at a university hospital. Patients were arbitrarily assessed by an ICU team consisting of medical and surgical doctors, nurses and physiotherapists within 24 hours after admission to ICU to discover whether their rehabilitation could be initiated according to the specific clinical trial and statement. As clinical characteristics, disease aetiology, comorbid conditions, and ICU treatment were obtained from an electronic database. We evaluated the probability of return to walking independence and return to home as in-hospital clinical outcomes. All patients were followed for five years and investigated all-cause and cardiovascular events after hospital discharge as long-term clinical outcomes. The associations between the implementation of CR during ICU treatment (ICU-CR) and clinical outcomes were evaluated using propensity score-matched analysis with adjustment for clinical characteristics in all matched patients and various subgroups, including aged >65 years, surgical patients, emergency, and length of ICU stay ≥48 hours.

Results

Out of studied patients, 1092 patients received ICU-CR, the number of which positively correlated with year-trend (r=0.986, P<0.001). After propensity score matching with adjustment for clinical characteristics including calendar years, 758 patients were included for analysis (pairs of n=379 ICU-CR and non-ICU-CR). The ICU-CR was significantly associated with a higher probability of return to walking independence (incident rate ratio [IRR], 2.04; 95% confidence interval [CI], 1.77–2.36) and return to home (IRR, 1.22 95% CI, 1.05–1.41). These associations were consistently observed in various subgroups regarding CVD conditions (Figure 1). During the median follow-up periods of 2.6 years, all-cause clinical events and cardiovascular events occurred in 289 patients (38.1%) and 153 patients (20.2%), respectively. The ICU-CR showed significantly lower rates of five-year all-cause and cardiovascular events than non-ICU-CR (hazard ratio [95% CI] for all-cause events and cardiovascular events, 0.71 [0.56–0.89] and 0.69 [0.50–0.95], respectively, Figure 2).

Conclusions

The implementation of acute-phase CR in the ICU increased with year-trend, considered beneficial to improve in-hospital and long-term clinical outcomes in patients with CVD and various subgroups of relatively severe disease conditions.

Funding Acknowledgement

Type of funding sources: None.

Cancer as a risk factor for physical dysfunction and poor prognosis in patients with cardiovascular disease

Introduction

The emerging interdisciplinary field of cardio-oncology is of interest to clinicians because a history of cancer or cancer treatment is considered a severe risk factor for cardiovascular disease (CVD). Both cancer and CVD can reduce skeletal muscle mass; together, they can lead to a poorer prognosis. However, it is unclear whether a patient's cancer history can lower physical function and lead to a poor prognosis with the coexistence of cancer history and physical dysfunction in patients with CVD. This study aimed to identify the relationship between cancer history and physical function, as well as the prognostic value of their combination, in patients with CVD.

Methods

We reviewed 3,640 patients with CVD (mean age, 67.9±13.5 years) who underwent physical-function tests (gait speed and 6-min walking distance [6MWD]). We performed multivariate linear regression analysis to assess potential associations between cancer history and physical-function tests in patients with CVD. Additionally, we used the Kaplan–Meier curve and Cox regression analyses to assess survival and prognostic significance for patients divided into four groups according to the presence or absence of cancer history and high or low physical function.

Results

In multivariate linear regression analysis, cancer history was independently associated with lower gait speed and 6MWD (gait speed, P=0.048 and 6MWD, P=0.040). A total of 581 deaths occurred over a median follow-up period of 3.08 years (interquartile range: 1.36–5.27). For all-cause mortality, patients with a history of cancer and reduced physical function were found to have a significantly higher mortality risk even after adjusting for several covariates (gait speed, HR: 1.66, P=0.003 and 6MWD, HR: 1.71, P=0.003).

Conclusion

Cancer history was correlated with physical dysfunction in patients with CVD. Moreover, the coexistence of cancer history and physical dysfunction resulted in poorer prognosis in patients with CVD.

Funding Acknowledgement

Type of funding sources: None.

Sex differences in frequency of instrumental activities of daily living after cardiac rehabilitation and its impact on long-term mortality in patients with heart failure

Introduction

While the major outcome of cardiac rehabilitation for heart failure (HF) is the improvement of exercise tolerance, prognosis, and quality of life, instrumental activities of daily living (IADL) has also been focused on as one of the its outcomes. IADL has been reported to be associated with all-cause mortality and quality of life in community-dwelling people and in patients with stable heart disease, but no report has examined the relationship between IADL after cardiac rehabilitation for HF and prognosis. In addition, it is assumed that sex differences may affect the frequency of performing each component of IADL, but there are no reports examining the association with prognosis by sex.

Purpose

The present study aimed to investigate the sex differences in frequency of IADL and its impact on outcomes.

Methods

We retrospectively studied 490 consecutive patients who were admitted due to acute decompensated HF and participated in outpatient cardiac rehabilitation after discharge. The study was performed in accordance with the tenets of the Declaration of Helsinki, and the protocol was approved by the Ethics Committee of our institution. IADL frequency was assessed using the questionnaire-based Frenchay Activities Index (FAI). The primary endpoint was all-cause death and secondary endpoint was combined events (all-cause death and/or readmission due to HF). We performed the Kaplan–Meier and log-rank tests and multivariable Cox regression analysis to evaluate the prognostic predictive capability of the FAI.

Results

The study population had a median age of 69 (interquartile range [IQR]: 58–76) years, and 33.9% of patients were females. The median FAI score was 24 (IQR: 16–29) points. According to the Youden index based on the area under the curve calculated by the receiver operating characteristics curve, the cut-off values of FAI for all-cause death in all-over, females, and males were 23, 22, and 23 points, respectively. Over a median follow-up period of 4.8 years (IQR: 2.3–6.6 years), all-cause death and combined events were occurred in 95 (19.4%) and 213 (43.5%), respectively. After adjustment for several pre-existing prognostic factors, IADL assessed by the FAI was independently associated with all-cause mortality (hazard ratio [HR]: 0.961, 95% confidence interval [CI]:0.937–0.986) and combined events (HR: 0.968, 95% CI: 0.952–0.985), respectively. In addition, there was no interaction between sex in prognostic capability (P=0.664).

Conclusion

Lower IADL frequency assessed by FAI at the end of outpatient cardiac rehabilitation was shown to be associated with poorer prognosis in patients with HF, regardless of sex. The IADL level is generally higher in females than in males but seems to be a useful marker for risk stratification at the end of cardiac rehabilitation in both females and males.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Grant-in-Aid [JSPS KAKENHI Grant Number JP 19K19884]

Impact of small-airway disease on exercise intolerance and long-term outcomes in patients with heart failure and reduced or preserved ejection fraction

Introduction

Exercise intolerance in patients with heart failure (HF) is a strong indicator of a poor prognosis. As the respiratory impairment in HF patients, the small airway is reportedly more susceptible than central airways, which results in increased airway resistance and may cause poor outcomes. However, the impact of small-airway disease (SAD) on exercise intolerance and prognosis in patients with HF is still unclear.

Purpose

We investigated the associations between SAD and exercise intolerance in patients with HF, and the clinical significance of SAD for long-term clinical events with a reduced or preserved ejection fraction.

Methods

We reviewed 1015 patients with HF (mean age, 66.9±14.6 years; male, 64.5%) admitted for medical treatment. Patients with a prior history of chronic respiratory disease or an obstructive lung pattern – defined as the forced expiratory volume (%) in 1 s relative to <70% forced vital capacity using spirometry – were excluded. Characteristics including HF aetiology, comorbidities conditions, medications, blood parameters, and echocardiographic variables were obtained from clinical records. All patients underwent spirometry at hospital discharge, and SAD was defined as the maximum mid-expiratory flow (%) relative to a <60% predicted value. At hospital discharge, we measured 6-min walk distance (6MWD), and <300 m was considered as exercise intolerance. The primary endpoint was a composite clinical event of all-cause death and/or unplanned readmission for HF. Multivariate logistic regression analysis was used to assess the association between SAD and exercise intolerance. The multivariate Cox proportional hazard model was used to clarify whether SAD was an independent predictor for the incidence of clinical events. We also performed subgroup analyses in each multivariate analysis based on a left ventricular ejection fraction (LVEF) of 40%.

Result

SAD was observed in 479 (47.2%) patients. LVEF subgroups included 458 (45.1%) and 518 (51.0%) patients with LVEF <40% and ≥40%, respectively. After adjusting for clinical characteristics, SAD was independently associated with 6MWD <300 m (Figure 1). Moreover, this association was consistently observed in the LVEF <40% and ≥40% (Figure 1). During the median follow-up period of 1.5 years, all-cause death/readmission occurred in 431 patients (42.5%), and the incidence rate was 17.5/100 person-years. In the multivariate Cox proportional hazard model, SAD was independently associated with lower event-free survival rates in all patients and the LVEF <40% subgroup, but not LVEF ≥40% subgroup (Figure 2A, B, and C, respectively).

Conclusion

This study is the first to reveal that SAD is associated with exercise intolerance in patients with HF regardless of LVEF. Moreover, SAD may have a predictive significance for long-term outcomes in patients with HF and subgroups with reduced, but not preserved ejection fraction.

Funding Acknowledgement

Type of funding sources: None.

Numerical investigation of effects of tongue articulation and velopharyngeal closure on the production of sibilant [s]

A numerical simulation of sibilant /s/ production with the realistically moving vocal tract was conducted to investigate the flow and acoustic characteristics during the articulation process of velopharyngeal closure and tongue movement. The articulation process was simulated from the end of /u/ to the middle of /s/ in the Japanese word /usui/, including the tongue elevation and the velopharyngeal valve closure. The time-dependent vocal tract geometry was reconstructed from the computed tomography scan. The moving immersed boundary method with the hierarchical structure grid was adopted to approach the complex geometry of the human speech organs. The acoustic characteristics during the co-articulation process were observed and consistent with the acoustic measurement for the subject of the scan. The further simulations with the different closing speeds of the velopharyngeal closure showed that the far-field sound during the co-articulation process was amplified with the slower closing case, and the velum closure speed was inverse proportional to the sound amplitude with the slope value of − 35.3 dB s/m. This indicates possible phonation of indistinguishable aeroacoustics sound between /u/ and /s/ with slower velopharyngeal closure.

Taste Impairments in a Parkinson’s Disease Model Featuring Intranasal Rotenone Administration in Mice

Background: Taste impairments are often accompanied by olfactory impairments in the early stage of Parkinson’s disease (PD). The development of animal models is required to elucidate the mechanisms underlying taste impairments in PD. Objective: This study was conducted to clarify whether the intranasal administration of rotenone causes taste impairments prior to motor deficits in mice. Methods: Rotenone was administrated to the right nose of mice once a day for 1 or 4 week(s). In the 1-week group, taste, olfactory, and motor function was assessed before and after a 1-week recovery period following the rotenone administration. Motor function was also continuously examined in the 4-weeks group from 0 to 5 weeks. After a behavioral test, the number of catecholamine neurons (CA-Nos) was counted in the regions responsible for taste, olfactory, and motor function. Results: taste and olfactory impairments were simultaneously observed without locomotor impairments in the 1-week group. The CA-Nos was significantly reduced in the olfactory bulb and nucleus of the solitary tract. In the 4-week group, locomotor impairments were observed from the third week, and a significant reduction in the CA-Nos was observed in the substantia nigra (SN) and ventral tegmental area (VTA) at the fifth week along with the weight loss. Conclusion: The intranasal administration of rotenone caused chemosensory and motor impairments in an administration time-period dependent manner. Since chemosensory impairments were expressed prior to the locomotor impairments followed by SN/VTA CA neurons loss, this rotenone administration model may contribute to the clarification of the prodromal symptoms of PD.

Relationship between the spread of coronavirus disease 2019, social frailty and depressive symptoms in patients with heart failure

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): the Japan Society for the Promotion of Science (JSPS) KAKENHI

Background

Owing to the spread of coronavirus disease 2019 (COVID-19), people have refrained from going out unnecessarily and have been maintaining social distance. These new lifestyle approaches have affected people physically, psychologically, and socially. Patients with heart failure (HF) are more likely to have social frailty, physical frailty, cognitive impairment, and depressive symptoms, and an overlap of these conditions leads to adverse events. Therefore, multi-domain assessment and understanding of the condition of patients with HF are important for disease management. The spread of COVID-19 is a predicted risk factor for these events, but its impact in patients with HF has not been investigated.

Purpose

We investigated whether the spread of COVID-19 is associated with the development of the multi-domain of frailty in patients with HF.

Methods

Patients who were independent in their daily activities before admission were included in the study. The presence of social frailty (Makizako’s five items), physical frailty (Fried phenotype model), cognitive impairment (Mini-Cog), and depressive symptoms (the Patient Health Questionnaire-2) in patients with HF were assessed at hospital discharge. Logistic regression analyses were used to examine the impact of the spread of COVID-19 on the development of the multi-domain of frailty in patients with HF.

Results

We included 482 patients in this study. Median patient age was 74 years, and 64.5% were male. In multivariate logistic regression analyses, the spread of COVID-19 was significantly associated with the development of social frailty (odds ratio [OR]: 1.15, 95% confidence interval [CI]: 1.02–1.30) and depressive symptoms (OR: 1.14, 95% CI: 1.02–1.27) but not with the development of physical frailty (OR: 1.24, 95% CI: 0.51–3.02) and cognitive impairment (OR: 1.72, 95% CI: 0.80–3.73).

Conclusion

The spread of COVID-19 was associated with the development of social frailty and depressive symptoms in patients with HF. Evaluation of social frailty and depressive symptoms during hospitalization would support disease management and understand their social and psychological conditions specific to the spread of COVID-19.

Prevalence of metabolic dysfunction-associated fatty liver disease and its association with physical function in patients with acute coronary syndrome

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): JSPS KAKENHI

Background

It is widely known that patients with acute coronary syndrome (ACS) are at increased risk of nonalcoholic fatty liver disease (NAFLD), which is linked to sarcopenia and physical dysfunction. However, the relationship between metabolic dysfunction-associated fatty liver disease (MAFLD) and physical dysfunction remains unclear.

Purpose

The purpose of this study was to investigate the prevalence of MAFLD in patients with ACS to assess the relationship between MAFLD and muscle strength, walking speed, and 6-minute walking distance (6 MWD).

Methods

We reviewed patients with ACS who were assessed for hepatic steatosis using the fatty liver index, and the results were further assessed to determine the presence of MAFLD. Multiple regression analysis was used to examine the association between MAFLD and physical function.

Results

Among 479 enrolled hospitalized patients, MAFLD was identified in 234 (48.9%) patients. We conducted a multiple regression analysis in which MAFLD was independently associated with lower leg strength, gait speed, and 6 MWD (leg strength, P = 0.023; gait speed, P = 0.002 and 6 MWD, P = 0.017). Furthermore, having more metabolic impairment was still associated with lower physical function decline (leg strength, P for trend = 0.002; gait speed, P for trend = 0.019 and 6 MWD, P for trend = 0.003).

Conclusions

MAFLD is common in hospitalized patients with ACS, and most patients with MAFLD have many overlapping metabolic abnormalities. MAFLD is associated with impaired physical function, and the greater the number of overlapping metabolic abnormalities, the worse the motor function.

Skeletal muscle mass metrics as factors in the prognosis of heart failure patients

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): JSPS KAKENHI Grant

Background

Sarcopenia is a chronic condition that is characterized by the loss of skeletal muscle mass with declining muscle strength and/or performance that occurs gradually with aging. It has been reported that sarcopenia is highly prevalent in patients with heart failure (HF) and is a poor prognostic factor. Therefore, it is important to accurately assess skeletal muscle mass in patients with HF. However, there are no reports that have simultaneously examined different skeletal muscle mass metrics as factors in the prognosis of HF patients.

Purpose

The purpose of this study is to examine if the different skeletal muscle mass metrics are associated with the prognosis of HF patients.

Methods

We examined a total of 869 patients with HF, aged ≥20 years (73 [63, 80] years; 537 males), who were admitted to our hospital and participated in an inpatient cardiac rehabilitation program. We used skeletal muscle mass index (SMI) as measured by bioelectrical impedance analysis (BIA), mid-upper arm circumference (MUAC), arm muscle circumference (AMC), and calf circumference (CC) as metrics of skeletal muscle mass. The primary outcome was all-cause deaths, and secondary outcome was HF readmission. To investigate the association between each skeletal muscle mass metric and prognosis, patients were divided into three groups according to the tertiles of SMI, MUAC, AMC, and CC. In addition, cumulative event rates of survival curves, Gray test, and Fine & Gray test were performed to evaluate the prognostic predictive capability.

Results

Over a median follow-up period of 0.9 years (interquartile 0.4–1.9) years, a total of 80 deaths and 195 HF readmissions occurred in the patients. Cumulative event rates of survival curves and Gray test showed that there was a significant decrease in all-cause mortality and HF readmission in the high MUAC group and high AMC group compared to their respective low groups (P < 0.05). Fine & Gray test after multivariate adjustment showed significantly better prognosis in the high MUAC group and high AMC group compared to their respective low groups (All-cause mortality: high MUAC group, subdistribution hazard ratio [sHR] = 0.42, 95% confidence interval [CI] = 0.20-0.88, P < 0.05; high AMC group, sHR = 0.34, 95%CI = 0.16-0.72 P < 0.05, HF readmission: high MUAC group, sHR = 0.69, 95%CI = 0.47-1.00, P < 0.05; high AMC group, sHR = 0.63, 95%CI = 0.43-0.93, P < 0.05).

Conclusion

Patients with HF who maintained high MUAC and high AMC had a good prognosis. CC and SMI were not associated with the prognosis of HF patients. This suggests the importance of evaluating MUAC and AMC in HF patients.

Estimation of sibilant groove formation and sound generation from early hominin jawbones

The speech production capability of sibilant fricatives of early hominin was assessed by interpolating the modern human vocal tract to an Australopithecine specimen based on the jawbone landmarks, and then simulating the airflow and sound generation. The landmark interpolation demonstrates the possibility to form the sibilant groove in the anterior part of the oral tract, and results of the aeroacoustic simulation indicate that the early hominins had the potential to produce the fricative broadband noise with a constant supply of airflow to the oral cavity, although the ancestor's tongue deformation ability is still uncertain, and the results are highly speculative.

Associations between kidney function and outcomes following cardiac rehabilitation in patients with heart failure

Background

Kidney dysfunction is considered one of the most prevalent comorbidities in patients with heart failure (HF). A combination of HF and kidney dysfunction is associated with peripheral muscle impairment, exercise intolerance, and poor prognosis. Conversely, cardiac rehabilitation (CR) for HF patients has been recognized to improve their clinical outcomes. However, the impact of kidney function on responses to CR in patients with HF is still unclear.

Purpose

This study aimed to investigate the associations between baseline kidney function and outcomes following CR including changes in physical function and prognosis in HF patients.

Methods

We reviewed a total of 3,727 patients who were admitted for HF treatment and underwent comprehensive CR during hospitalization. In addition to clinical characteristics, we assessed the kidney function using estimated glomerular filtration rate (eGFR) based on serum creatinine level at hospital discharge as baseline. The quadriceps strength (QS) and 6-minute walk distance (6MWD) were measured as muscle strength and functional capacity, respectively, at baseline. We also remeasured these parameter 5 months after hospital discharge in patients who participated in outpatient CR. The association between participation in outpatient CR and composite outcome of all-cause death and/or unplanned readmission were assessed using the multivariate Cox proportional hazard models in a subgroup of baseline eGFR. We also compared the changes in QS and 6MWD (ΔQS and Δ6MWD) between the eGFR stages.

Results

During the median follow-up period of 1.9 years, all-cause death/readmission occurred in 1604 (43.0%) patients, and their rate of incidence was 20.9/100 person-years. Out of studied patients, 1,585 (42.5%) patients participated in outpatient CR that was significantly associated with lower incidences of all-cause clinical events in patients with both eGFR ≥60 (adjusted hazard ratio [HR]: 0.73, 95% confidence interval [CI]: 0.60–0.89, P=0.002) and eGFR <60 (adjusted HR: 0.88, 95% CI: 0.78–0.99, P=0.045), but those with an eGFR <60 showed significant interaction between CR participation and adverse clinical events (interaction P<0.035, Figure 1). Among the outpatient CR participants, QS and 6MWD were significantly higher after 5-month CR than those at baseline (P<0.001, respectively), but the low baseline eGFR correlated with low ΔQS and Δ6MWD (trend P<0.001, respectively) even after adjustment for clinical confounding factors (Figure 2).

Conclusions

Although the outcomes following CR is affected by baseline kidney function, outpatient CR is significantly associated with the positive change in physical function and better prognosis in HF patients with low kidney function.

Funding Acknowledgement

Type of funding sources: None.

Intraoral image generation by progressive growing of generative adversarial network and evaluation of generated image quality by dentists

Dentists need experience with clinical cases to practice specialized skills. However, the need to protect patient's private information limits their ability to utilize intraoral images obtained from clinical cases. In this study, since generating realistic images could make it possible to utilize intraoral images, progressive growing of generative adversarial networks are used to generate intraoral images. A total of 35,254 intraoral images were used as training data with resolutions of 128 × 128, 256 × 256, 512 × 512, and 1024 × 1024. The results of the training datasets with and without data augmentation were compared. The Sliced Wasserstein Distance was calculated to evaluate the generated images. Next, 50 real images and 50 generated images for each resolution were randomly selected and shuffled. 12 pediatric dentists were asked to observe these images and assess whether they were real or generated. The d prime of the 1024 × 1024 images was significantly higher than that of the other resolutions. In conclusion, generated intraoral images with resolutions of 512 × 512 or lower were so realistic that the dentists could not distinguish whether they were real or generated. This implies that the generated images can be used in dental education or data augmentation for deep learning, without privacy restrictions.

Numerical investigation of effects of incisor angle on production of sibilant /s/

The effects of the inclination angle of the incisor on the speech production of the fricative consonant /s/ was investigated using an implicit compressible flow solver. The hierarchical structure grid was applied to reduce the grid generation time for the vocal tract geometry. The airflow and sound during the pronunciation of /s/ were simulated using the adaptively switched time stepping scheme, and the angle of the incisor in the vocal tract was changed from normal position up to 30°. The results showed that increasing the incisor angle affected the flow configuration and moved the location of the high turbulence intensity region thereby decreased the amplitudes of the sound in the frequency range from 8 to 12 kHz. Performing the Fourier transform on the velocity fluctuation, we found that the position of large magnitudes of the velocity at 10 kHz shifted toward the lip outlet when the incisor angle was increased. In addition, separate acoustic simulations showed that the shift in the potential sound source position decreased the far-field sound amplitudes above 8 kHz. These results provide the underlying insights necessary to design dental prostheses for the production of sibilant fricatives.

Associations of severity of liver damages with physical function and prognosis in patients with heart failure

Funding Acknowledgements

Type of funding sources: None.

Introduction

Heart failure (HF) and liver dysfunction often coexist because of complex cardiohepatic interactions, which adversely affects prognosis. However, the association between liver dysfunction and physical dysfunction, and between coexistence of both and prognosis in HF patients remains unclear.

Purpose

We evaluated the associations of severity of liver damage and physical function and prognosis in patients with HF.

Methods

The study population consisted of 895 patients with HF (mean age, 69.4 ± 14.2 years) who underwent liver function test using model for end-stage liver disease excluding international normalized ratio (MELD-XI) score and physical function test (grip strength, leg strength, gait speed, and 6-minute walking distance [6MWD]). The associations between MELD-XI score and physical function were assessed by multivariate linear regression model analysis. Moreover, we investigated the prognostic value of coexistence of liver dysfunction and physical dysfunction. The endpoint was all-cause mortality.

Results

After adjusting for covariates, MELD-XI score was independently associated with lower grip strength, leg strength, gait speed, and 6MWD (P < 0.001). In addition, hierarchical multivariate linear regression analysis revealed that adding MELD-XI scores or BNP explained additional variance in the physical function measures. The MELD-XI score added to the clinical model was significantly more predictive of physical function (grip strength, change in F: 27.105, P < 0.001; leg strength, change in F: 33.980, P < 0.001; gait speed, change in F: 22.826, P < 0.001; 6MWD, change in F: 59.193, P < 0.001) than BNP added to the clinical model. Eighty-six deaths occurred over a median follow-up period of 1.67 years (interquartile range: 0.62 – 3.04). Patients with high MELD-XI score and reduced physical function were found to have significantly higher mortality risk even after adjusting for several covariates (grip strength, hazard ratio [HR] = 3.80 [95% confidence interval (CI) = 2.04 – 7.08], P < 0.001; leg strength, HR = 4.65 [95% CI = 2.47 - 8.75], P < 0.001 and gait speed, HR = 2.49 [95% CI = 1.43 - 4.33], P = 0.001; 6MWD, HR = 5.48 [95% CI = 2.88 - 10.41], P < 0.001).

Conclusions

Liver dysfunction was correlated with reduced physical function. Moreover, the coexistence of lower physical function and liver dysfunction considerably affected prognosis in patients with HF.

Abstract Figure. Kaplan–Meier survival curves

Low skeletal muscle density combined with muscle dysfunction predicts adverse events after adult cardiovascular surgery

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): This study was supported by the Grant for Japan Society for the Promotion of Science (JSPS) KAKENHI.

Introduction

Although muscle dysfunction is widely known as a poor prognostic factor in patients with cardiovascular disease, no study has examined whether the addition of low skeletal muscle density (SMD) assessed by computed tomography (CT) to muscle dysfunction is useful.

Purpose

The present study aimed to examine whether SMDs can strengthen the predictive ability of muscle dysfunction for adverse events in patients who underwent cardiovascular surgery.

Methods

We retrospectively reviewed 853 patients (median age: 69 years, 65.1% male) aged ≥40 years who had preoperative CT for risk management purposes and muscle dysfunctions measured during postoperative cardiac rehabilitation. Muscle dysfunctions were determined from weakness (low grip strength) and slowness (slow gait speed) based on the Asia Working Group for Sarcopenia. Low SMD based on transverse abdominal CT images was defined as a mean Hounsfield unit of the psoas muscle <45. To examine the complementary prognostic value for all-cause deaths, all-cause events, and cardiovascular-related events when low SMDs were added to four patterns of muscle dysfunction (weakness only, slowness only, weakness or slowness, and weakness and slowness), the continuous net reclassification improvement (cNRI) and integrated discrimination improvement (IDI) index were calculated.

Results

For all definitions of muscle dysfunction, the addition of SMDs was shown to significantly improve the cNRI (estimates: 0.377 to 0.468 for all-cause death, 0.220 to 0.248 for all-cause events, 0.308 to 0.322 for cardiovascular-related events) and IDI (estimates: 0.005 to 0.011 for all-cause death, 0.005 to 0.010 for all-cause events, 0.009 to 0.012 for cardiovascular-related events) in all analyses. Low SMDs combined with muscle dysfunctions were associated with the highest risk of all-cause death (Figure 1: A-D). Patients with neither low SMDs nor muscle dysfunction had the lowest risk of all-cause events and cardiovascular-related events (Figure1: E-L).

Conclusion

The predictive ability of muscle dysfunction for adverse events was consistently increased by addition of SMDs in patients who underwent cardiovascular surgery. Our results suggest that when CT is performed for any clinical investigation, the addition of the organic assessment of skeletal muscle can strengthen the diagnostic accuracy of muscle wasting.

Abstract Figure 1

Quantification of Oscillatory Shear Stress from Reciprocating CSF Motion on 4D Flow Imaging

BACKGROUND AND PURPOSE

Oscillatory shear stress could not be directly measured in consideration of direction, although cerebrospinal fluid has repetitive movements synchronized with heartbeat. Our aim was to evaluate the important of oscillatory shear stress in the cerebral aqueduct and foramen magnum in idiopathic normal pressure hydrocephalus by comparing it with wall shear stress and the oscillatory shear index in patients with idiopathic normal pressure hydrocephalus.

MATERIALS AND METHODS

By means of the 4D flow application, oscillatory shear stress, wall shear stress, and the oscillatory shear index were measured in 41 patients with idiopathic normal pressure hydrocephalus, 23 with co-occurrence of idiopathic normal pressure hydrocephalus and Alzheimer-type dementia, and 9 age-matched controls. These shear stress parameters at the cerebral aqueduct were compared with apertures and stroke volumes at the foramen of Magendie and cerebral aqueduct.

RESULTS

Two wall shear stress magnitude peaks during a heartbeat were changed to periodic oscillation by converting oscillatory shear stress. The mean oscillatory shear stress amplitude and time-averaged wall shear stress values at the dorsal and ventral regions of the cerebral aqueduct in the idiopathic normal pressure hydrocephalus groups were significantly higher than those in controls. Furthermore, those at the ventral region of the cerebral aqueduct in the idiopathic normal pressure hydrocephalus group were also significantly higher than those in the co-occurrence of idiopathic normal pressure hydrocephalus with Alzheimer-type dementia group. The oscillatory shear stress amplitude at the dorsal region of the cerebral aqueduct was significantly associated with foramen of Magendie diameters, whereas it was strongly associated with the stroke volume at the upper end of the cerebral aqueduct rather than that at the foramen of Magendie.

CONCLUSIONS

Oscillatory shear stress, which reflects wall shear stress vector changes better than the conventional wall shear stress magnitude and the oscillatory shear index, can be directly measured on 4D flow MR imaging. Oscillatory shear stress at the cerebral aqueduct was considerably higher in patients with idiopathic normal pressure hydrocephalus.

Mechanical effects of distributed fibre orientation in the periodontal ligament of an idealised geometry

In this study, we computationally assess the effects of the distributed fibre orientation in the periodontal ligament (PDL) on mechanical responses of the tooth-PDL complex. An idealised axial-symmetric geometry of a tooth-PDL complex was constructed. The fibre orientation in the PDL was modelled as a trigonometric function based on anatomical knowledge, and the PDL was modelled as a transversely isotropic hyperelastic material dependent on fibre orientations. Parametric studies of the fibre orientation on the mechanical responses of the tooth-PDL complex were conducted. Obtained results showed that the anatomically consistent fibre orientation functions as a supporting structure against not only vertical but also horizontal loads.

Correlation between respiratory muscle weakness and frailty status as risk markers for prognosis in patients with cardiovascular disease

Background

Respiratory muscle weakness (RMW), frequently observed in patients with cardiovascular disease (CVD), is documented as a predictor for exercise intolerance and poor prognosis. On the other hand, frailty is commonly associated with disease condition, leading to increased risk of morbidity and mortality. Although the developmental mechanism of RMW and frailty is partly similar, the relationship between these statuses remains unclear.

Purpose

We aimed to investigate the correlation between RMW and frailty and its impact on prognosis in patients with CVD.

Methods

We studied 771 consecutive patients (68.5±13.1 years, 256 females) who were hospitalized for CVD treatment and underwent cardiac rehabilitation during hospitalization. Patients who received thoracic surgery within the last 3 months or could not perform respiratory function test were excluded from this study. As patient characteristics, we obtained body mass index, comorbidity conditions, smoking history, blood examinations, echocardiographical variables, and lung function from medical database. The frailty status on admission was assessed using frailty score consisting of 5 items including gait speed, nutrition/shrinking, physical activity, forgetfulness, and emotions/exhaustion, and patients who had 3 items were defined as frailty. We also measured maximal inspiratory pressure (PImax) as respiratory muscle strength at hospital discharge, and RMW was defined with PImax <70% of predicted value. Primary end-point was all-cause clinical events including all-cause death and/or unplanned readmission after hospital discharge. We examined the prevalence of RMW and frailty and the correlation between these statuses. The relationships of RMW with the clinical events for each presence or absence of frailty were also investigated using multivariate Cox proportional hazard models.

Results

RMW and frailty were defined in 163 (33.5%) and 126 (28.7%) patients, respectively, and 95 patients (12.4%) among them showed an overlap of both statuses (Figure 1). Frailty was detected as a significant indicator of RMW after adjusting for confounding factors (adjusted odds ratio: 1.57, 95% CI: 1.12–2.19, P=0.009). Over the median follow-up periods of 1.2 years, all-cause clinical events occurred in 154 patients (20.0%). RMW was significantly and independently associated with increased incidence of all-cause clinical events in patients with both non-frailty (adjusted hazard ratio [HR]: 1.64, 95% CI: 1.09–2.46, P=0.017) and frailty (adjusted HR: 1.97, 95% CI: 1.14–3.42, P=0.015) even after adjusting for clinical confounding factors (Figure 2).

Conclusions

This study is the first to demonstrate that RMW correlated to frailty in patients with CVD, and 12.4% of patients had overlap status. Moreover, RMW was significantly associated with an increased risk of all-cause clinical events in patients with CVD and frailty.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Japan Society for the Promotion of Science Grant-in-Aid

Identification of dental implants using deep learning-pilot study

Background

In some cases, a dentist cannot solve the difficulties a patient has with an implant because the implant system is unknown. Therefore, there is a need for a system for identifying the implant system of a patient from limited data that does not depend on the dentist’s knowledge and experience. The purpose of this study was to identify dental implant systems using a deep learning method.

Methods

A dataset of 1282 panoramic radiograph images with implants were used for deep learning. An object detection algorithm (Yolov3) was used to identify the six implant systems by three manufactures. To implement the algorithm, TensorFlow and Keras deep-learning libraries were used. After training was complete, the true positive (TP) ratio and average precision (AP) of each implant system as well as the mean AP (mAP), and mean intersection over union (mIoU) were calculated to evaluate the performance of the model.

Results

The number of each implant system varied from 240 to 1919. The TP ratio and AP of each implant system varied from 0.50 to 0.82 and from 0.51 to 0.85, respectively. The mAP and mIoU of this model were 0.71 and 0.72, respectively.

Conclusions

The results of this study suggest that implants can be identified from panoramic radiographic images using deep learning-based object detection. This identification system could help dentists as well as patients suffering from implant problems. However, more images of other implant systems will be necessary to increase the learning performance to apply this system in clinical practice.

A system for designing removable partial dentures using artificial intelligence. Part 1. Classification of partially edentulous arches using a convolutional neural network

PURPOSE

The purpose of this study was to develop a method for classifying dental arches using a convolutional neural network (CNN) as the first step in a system for designing removable partial dentures.

METHODS

Using 1184 images of dental arches (maxilla: 748 images; mandible: 436 images), arches were classified into four arch types: edentulous, intact dentition, arches with posterior tooth loss, and arches with bounded edentulous space. A CNN method to classify images was developed using Tensorflow and Keras deep learning libraries. After completion of the learning procedure, the diagnostic accuracy, precision, recall, F-measure and area under the curve (AUC) for each jaw were calculated for diagnostic performance of learning. The classification was also predicted using other images, and percentages of correct predictions (PCPs) were calculated. The PCPs were compared with the Kruskal-Wallis test (p = 0.05).

RESULTS

The diagnostic accuracy was 99.5% for the maxilla and 99.7% for the mandible. The precision, recall, and F-measure for both jaws were 0.25, 1.0 and 0.4, respectively. The AUC was 0.99 for the maxilla and 0.98 for the mandible. The PCPs of the classifications were more than 95% for all types of dental arch. There were no significant differences among the four types of dental arches in the mandible.

CONCLUSIONS

The results of this study suggest that dental arches can be classified and predicted using a CNN. Future development of systems for designing removable partial dentures will be made possible using this and other AI technologies.

Mineral trioxide aggregate suppresses pro-inflammatory cytokine expression via the calcineurin/nuclear factor of activated T cells/early growth response 2 pathway in lipopolysaccharide-stimulated macrophages

AIM

To elucidate mechanisms by which mineral trioxide aggregate (MTA) suppresses pro-inflammatory cytokine mRNA expression in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages.

METHODOLOGY

Mineral trioxide aggregate extracts were prepared by immersing set ProRoot MTA in culture medium. RAW264.7 cells were cultured in the presence of LPS and MTA extracts. mRNA expression levels of interleukin (IL)-1α, IL-6, early growth response 2 (Egr2), suppressor of cytokine signalling 3 (Socs3) and IL-10 were quantified with reverse transcription-quantitative polymerase chain reaction. Phosphorylation of nuclear factor-kappa B (NF-κB) p65 in RAW264.7 cells was analysed by Western blotting. Intracellular calcium imaging was performed with Fluo-4 AM. The activity of nuclear factor of activated T cells (NFAT) was determined by luciferase assays. Enforced expression and silencing of Egr2 in RAW264.7 cells were carried out using an expression vector and specific RNAi, respectively. In vivo kinetics of Egr2⁺ cells in MTA-treated rat molar pulp tissues were examined using immunohistochemistry. Data were analysed by one-way analysis of variance, followed by the Tukey-Kramer test (P < 0.05).

RESULTS

Exposure to MTA extracts resulted in reduced mRNA expression levels of IL-1α and IL-6, as well as reduced expression of phosphorylated NF-κB, in LPS-stimulated RAW264.7 cells. Exposure to MTA extracts induced Ca²⁺ influx, which was blocked by NPS2143, an antagonist of calcium-sensing receptor (CaSR); Ca²⁺ influx then triggered activation of calcineurin/NFAT signalling and enhanced mRNA expression of Egr2. Enforced expression of Egr2 in RAW264.7 cells promoted the expression of both IL-10 and Socs3. In vivo application of MTA onto rat molar pulp tissue resulted in the appearance of Egr2-expressing cells that coexpressed CD163, a typical M2 macrophage marker.

CONCLUSIONS

Mineral trioxide aggregate extracts induced downregulation of IL-1α and IL-6 in LPS-stimulated RAW264.7 cells via CaSR-induced activation of calcineurin/NFAT/Egr2 signalling and subsequent upregulation of IL-10 and Socs3.

Challenges in a population-based registry of cardiovascular disease in Shiga, Japan

Background

Stroke and cardiovascular disease are one of the leading causes of death and disability in Japan. In order to investigate current burden, we conduct a population-based registry of cardiovascular disease in Shiga Prefecture, Japan since 2012. We will demonstrate challenges in conduct of the registry study.

Methods

In 2012, we established the Shiga Stroke Registry (SSR), a multicenter population-based registry study designed to build a complete information system for the management of stroke in Shiga Prefecture, Japan. The registry uses local monitoring, combined with remote data collection and quality control systems, to create an integrated surveillance system among a network of all acute care hospitals with neurology/neurosurgery facilities and smaller hospitals with rehabilitation facilities in the region. In 2019, study name has changed to Shiga Stroke and Heart Attack Registry (SSHR) and additional registration of coronary heart disease and aortic disease have started. Each case is reviewed and adjudicated by 2 or more specialists.

Results

In the financial year of 2018 (from April to March), a total of 4809 stroke cases were identified. From December 2018 to April 2019, a total of 515 coronary heart and aortic diseases were identified. A total 10 nurses work full-time for the registry and it takes average of 1 hour to collect information for each patient. Challenges in conduct of the cardiovascular registry involve regulatory and ethical approval, funding, associations with local hospitals, non-standardized hospital diagnosis, staff training for comprehensive data collection including pathophysiology, examination and treatment, and quality control of data collection.

Conclusions

SSHR is a population-based registry of wide range of stroke and cardiovascular disease in Shiga Prefecture, Japan. In order to keep quality of the data, we put a lot of efforts on staff training and quality control.

Key messages

Population-based registry of wide range of stroke and cardiovascular disease in Shiga, Japan. In order to keep quality of the data, we put a lot of efforts on staff training and quality control.

A simplified vocal tract model for articulation of [s]: The effect of tongue tip elevation on [s]

Fricative consonants are known to be pronounced by controlling turbulent flow inside a vocal tract. In this study, a simplified vocal tract model was proposed to investigate the characteristics of flow and sound during production of the fricative [s] in a word context. By controlling the inlet flow rate and tongue speed, the acoustic characteristics of [s] were reproduced by the model. The measurements with a microphone and a hot-wire anemometer showed that the flow velocity at the teeth gap and far-field sound pressure started oscillating before the tongue reached the /s/ position, and continued during tongue descent. This behaviour was not affected by the changes of the tongue speed. These results indicate that there is a time shift between source generation and tongue movement. This time shift can be a physical constraint in the articulation of words which include /s/. With the proposed model, we could investigate the effects of tongue speed on the flow and sound generation in a parametric way. The proposed methodology is applicable for other phonemes to further explore the aeroacoustics of phonation.

P6331Influence of dynapenia and obesity on prognoses of elderly heart failure patients

Background

In elderly people, a decline in activities of daily living is more closely associated with low muscle strength (dynapenia) than with low muscle mass. Moreover, the combination of low muscle strength and obesity (dynapenic obesity) is associated with a higher risk of mortality than dynapenia or obesity alone, but its influence on prognosis is still unknown in elderly heart failure (HF) patients. To clarify these relationships may contribute to the development of rehabilitation programs for elderly HF patients and the improvement their prognoses in the future.

Purpose

We aimed to investigate the influence of dynapenia and obesity on prognoses of elderly HF patients.

Methods

We evaluated 1006 elderly HF patients aged ≥65 years (76.5±6.9 years, 579 males) who were admitted to our hospital and participated in an inpatient cardiac rehabilitation program. We assessed patients' characteristics, including body mass index (BMI) and handgrip strength during hospitalization. Patients with low handgrip strength (<26 kg and <18 kg in males and females, respectively) and high BMI (≥25 kg/m2) were considered to have dynapenia and obesity, respectively. Moreover, patients fulfilling the above two criteria (dynapenia, obesity) were considered to have dynapenic obesity. Patients were divided into four groups: normal, dynapenia only, obesity only, and dynapenic obesity. We compared survival rates among the four groups using the Kaplan-Meier method and log-rank test. To identify predictors for all-cause mortality, we performed Cox regression analysis.

Results

During the 8-year follow-up period, 228 patients (21.2%) died. Eight-year cumulative incidences of mortality were 35.4%, 26.0%, 62.6%, and 33.1% in the normal, obesity only, dynapenia only, and dynapenic obesity groups, respectively. Significantly lower survival rates were observed in the dynapenia only group than in the other 3 groups (log-rank: 28.893, P<0.001). Cox regression analysis, after adjusting for age and sex, showed significantly poor prognosis in the dyanapenia only group than in the other 3 groups (normal group, hazard ratio [HR] = 0.684, 95% confidence interval [CI] = 0.488–0.959, P=0.028; obesity only group, HR = 0.330, 95% CI = 0.182–0.598, P<0.001; dynapenic obesity group, HR = 0.390, 95% CI = 0.206–0.739, P=0.004).

Conclusion

Elderly HF patients with dynapenia alone had poor prognoses. Obesity may have protective effects on the survival of dynapenia patients with HF.

P2514Pupillary area predicts all-cause mortality in patients with cardiovascular disease

Background

Autonomic dysfunction is among the most important pathophysiological factors involved in the high mortality rate associated with cardiovascular disease (CVD). Autonomic function is generally evaluated by heart rate variability, which is obtained by Holter electrocardiography. However, the measurement of heart rate variability requires continuous electrocardiographic monitoring for 24 h, which is time consuming and not always feasible. The pupillary area is controlled by the autonomic nervous system; however, limited data are available regarding the utility of the pupillary area for predicting prognosis in patients with CVD.

Purpose

We aimed to investigate whether pupillary area can be used as a novel prognostic marker in patients with CVD.

Methods

We retrospectively reviewed 1342 consecutive Japanese patients hospitalized for CVD. The study was performed in accordance with the tenets of the Declaration of Helsinki, and the protocol was approved by the Ethics Committee of our University Hospital. The pupillary area measurement was performed on both eyes at least 7 days after hospitalization for CVD using a portable videopupillography system (Iriscorder Dual C10641; Hamamatsu Photonics, Hamamatsu, Japan) consisting of a goggle-shaped measurement portion with a charge-coupled device camera and a control portion with a video monitor and microcomputer with software for data analysis. After securing the goggles on the patient's face and fully covering the patient's eyes, a 5-minute period was allowed for dark adaptation. All patients were tested once between 09:00 and 12:00 h. The primary outcome of this study was all-cause mortality, and the endpoint time was calculated as the number of days from the date of pupillary area measurement up to three years. We performed the Kaplan–Meier and log-rank tests and multivariable Cox regression analysis to evaluate the prognostic predictive capability of the pupillary area.

Results

The study population had a mean age of 65±13 years, and 69.4% of the patients were male. The median of the pupillary area was 18.5 mm2 (interquartile range: 13.3–23.4 mm2). Over a median follow-up period of 1.9 years (interquartile range: 1.0–3.0 years), a total of 114 deaths occurred in the patient population. The Kaplan–Meier and log-rank tests revealed that all-cause mortality was significantly higher in the small pupillary area group than in the large pupillary area group (P<0.0001, Figure). Furthermore, Cox regression analysis indicated that the pupillary area was an independent predictor of mortality (Hazard ratio: 0.96; 95% confidence interval: 0.93–0.98; P=0.006) even after adjusting for several preexisting prognostic factors.

Kaplan-Meire Curve

Conclusion

The pupillary area can be an independent predictor of prognosis in patients with CVD, and our observations suggest that the assessment of the pupillary area can be useful as a new noninvasive prognostic predictor in patients with CVD.

298Change in respiratory muscle strength predicts clinical events in patients with chronic heart failure

Background

Respiratory muscle weakness, frequently observed in patients with chronic heart failure (CHF), has been documented as a predictor for poor prognosis. Several studies have reported that respiratory muscle training increases respiratory muscle strength and consequently improves exercise tolerance and quality of life in these patients. However, the relationship between the change in respiratory muscle strength and prognosis is still unclear.

Purpose

We aimed to investigate whether the change in respiratory muscle strength following cardiac rehabilitation predicts the incidence of clinical events in CHF patients.

Methods

We studied 348 patients with CHF who were hospitalized because of decompensated heart failure and received 5-month cardiac rehabilitation during hospitalization and after hospital discharge. Clinical characteristics including aetiology of heart failure, comorbidity conditions, medications, blood examination and echocardiographic variables were obtained from clinical records. We also measured maximal inspiratory pressure (PImax) as respiratory muscle strength at hospital discharge and 5 months later. The change of PImax (ΔPImax) between the 5-month observation period was examined. We followed up the patients after the observation period and investigated the incidence of all-cause mortality or all-cause unplanned readmission. In statistical analysis, patients were divided into two groups based on the median value of ΔPImax. We compared the event-free survival rate between the two groups using the Kaplan-Meier method with a log-rank test. We also performed the Cox proportional hazard model to clarify whether the ΔPImax was an independent predictor for the incidence of clinical events.

Results

Over a median follow-up of 1.6 years, 121 patients (34.8%) died or readmitted, and their rate of incidence was 21.7/100 person-years. The higher ΔPImax was associated significantly with a higher rate of event-free survival (Log-rank: 8.085, P=0.004, Figure 1). In univariate Cox proportional hazard model, ΔPImax was a significant predictor for the all-cause mortality/readmission (unadjusted hazard ratio for PImax increase of 10 cmH2O: 0.842, 95% CI: 0.763 - 0.931, P=0.001). Even after adjustment for clinical confounding factors including baseline PImax, ΔPImax remained significant and independent predictor for the all-cause mortality/readmission (adjusted hazard ratio for PImax increase of 10 cmH2O: 0.862, 95% CI: 0.763 - 0.974, P=0.017, Figure 2).

Conclusion

This study is the first to demonstrate that the change in respiratory muscle strength following cardiac rehabilitation independently predicts the incidence of clinical events in patients with CHF. The increase in PImax of 10 cmH2O was associated significantly with a 14% decrease in the rate of all-cause mortality or readmission.

Acknowledgement/Funding

JSPS KAKENHI JP16K16442

P3106Atrial fibrillation is not associated with the responses to exercise training in heart failure patients with preserved ejection fraction

Background

Atrial fibrillation (AF) is known as a common arrhythmia in heart failure patients with preserved left ventricular ejection fraction (HFpEF). Several studies have reported that HFpEF patients with AF show lower exercise tolerance and poorer prognosis as compared with those with sinus rhythm (SR). On the other hand, exercise training is documented to improve peripheral muscle function and exercise tolerance in HFpEF patients. However, the relationship between AF status and outcomes due to exercise training is still unclear in these patients.

Purpose

We aimed to investigate the influence of AF on the responses to outcomes with exercise training in HFpEF patients.

Methods

We studied 426 patients with HFpEF who received 5-month cardiac rehabilitation including exercise training during hospitalization and after hospital discharge. As clinical characteristics, we obtained body mass index, disease aetiology, comorbidity conditions, blood examination and echocardiographic variables from medical records. We also measured isometric quadriceps strength (QS) and 6-minute walk distance (6MWD) as peripheral muscle strength and exercise tolerance, respectively. The QS and 6MWD were assessed at hospital discharge as the baseline and 5 months later. AF status was determined by the presence on electrocardiogram at baseline 6MWD or medical history of AF during hospitalization. In statistical analysis, we compared baseline clinical characteristics, QS and 6MWD between the rhythm status (SR group or AF group). We also examined the changes in QS and 6MWD from baseline to the 5-month observation period (ΔQS and Δ6MWD) and compared them between the 2 groups using analysis of covariance with adjustment for baseline clinical confounding factors.

Results

At baseline, 289 patients (68%) were in SR, and 111 patients (26%) had AF. The AF was associated significantly with older age (P<0.001) and lower levels of estimated glomerular filtration rate (P=0.013), QS (P<0.001) and 6MWD (P<0.001) at baseline. The QS increased significantly from 25.2±11.0 kg at baseline to 30.8±13.0 kg after 5-month cardiac rehabilitation in the SR group, and from 21.1±8.3 kg to 26.0±9.4 kg in the AF group (P<0.001, respectively). The 6MWD also increased significantly from 394.8±129.2 to 463.5±133.5 meters in the SR, and from 343.7±107.9 to 403.0±114.5 meters in the AF (P<0.001, respectively). There were no significant differences in ΔQS and Δ6MWD between the SR and AF groups even after adjustment for clinical confounding factors including baseline QS or 6MWD (Figure).

Conclusions

The AF status in HFpEF patients was associated with older age, lower peripheral muscle function and also lower exercise tolerance at baseline, but not associated with the responses to exercise training.

Acknowledgement/Funding

JSPS KAKENHI JP16K16442

Aeroacoustic analysis on individual characteristics in sibilant fricative production

The cause of individual acoustic characteristics of sibilant fricatives /s/ and /ʃ/ was analyzed by extracting vocal tract geometries and conducting aeroacoustic experiments and simulations on each geometry. The vocal tract geometries of five Japanese subjects while sustaining /s/ and /ʃ/ were collected by magnetic resonance imaging. Flow and sound generation in the vocal tracts was predicted by large eddy simulations of compressible flow. The characteristic dimensions of the vocal tracts were extracted and simplified vocal tract models were constructed to clarify the relationship between the geometries and the acoustic characteristics. The acoustic characteristics of sounds generated by the simplified models agreed well with the sounds predicted by the simulation, indicating that the proposed model is able to express the individual characteristics in the production of sibilant fricatives. A comparison of the models showed that the volume and length of a space downstream from the constriction are key factors controlling the acoustic characteristics of each subject.

Association between excessive supraventricular ectopy and subclinical cerebrovascular disease: a population-based study

BACKGROUND AND PURPOSE

The association between an increased supraventricular ectopic beat (SVEB) and subclinical cerebrovascular disease remains unclear. Given the emerging concept that an increased SVEB is a marker of atrial cardiomyopathy or atherosclerosis burden, we sought to determine whether excessive supraventricular ectopic activity (ESVEA) is associated with a higher burden of subclinical cerebrovascular disease in the middle-aged to older cohort with neither apparent stroke nor atrial fibrillation.

METHODS

We conducted a cross-sectional population-based study of 462 men (mean age, 68.1 years) who underwent 24-h Holter electrocardiography and brain magnetic resonance imaging. ESVEA was defined as the presence of >10 SVEBs/h. Subclinical cerebrovascular diseases were defined as silent brain infarct (SBI), white matter hyperintensity (WMH) and intracranial atherosclerotic stenosis (ICAS). The association of ESVEA with the presence of subclinical cerebrovascular diseases was adjusted for potential confounding covariates.

RESULTS

A total of 88 (19.0%) participants had ESVEA and 81 (17.5%), 91 (19.7%) and 109 (23.6%) had SBI, WMH and ICAS, respectively. In multivariable-adjusted Poisson regression with robust error variance, ESVEA was associated with the presence of WMH (relative risk, 1.58; 95% confidence interval, 1.06-2.36) and ICAS (relative risk, 1.49; 95% confidence interval, 1.02-2.18), but not with that of SBI (relative risk, 1.32; 95% confidence interval, 0.86-2.01). These associations were consistent when the graded distributions of subclinical cerebrovascular diseases were applied as outcomes in ordinal logistic regression.

CONCLUSIONS

The ESVEA was independently associated with higher burdens of WMH and ICAS. This suggests that increased SVEBs might improve risk stratification of individuals at high risk of subclinical cerebrovascular disease and consequently apparent ischaemic stroke.

Prognostic usefulness of arm circumference and nutritional screening tools in older patients with cardiovascular disease

BACKGROUND AND AIM

Arm circumference (AC) and nutritional screening tools have been shown to have prognostic capability in patients with cardiovascular disease (CVD). This study aimed to compare the prognostic predictive capabilities of AC and nutritional screening tools in older patients with CVD.

METHODS AND RESULTS

The study population consisted of 949 admitted patients ≥60 years old with CVD. Patients underwent AC measurement and nutritional screening before hospital discharge. We used the controlling nutritional status index (CONUT), the geriatric nutritional risk index (GNRI), and the prognostic nutritional index (PNI) as nutritional screening tools. The end point of the study was all-cause mortality. The mean age of the study population was 72.3 ± 7.2 years, and 68.2% of the patients were male. A total of 130 deaths occurred over a median follow-up period of 2.2 years (interquartile range, 1.1-3.8 years). After adjusting for other prognostic factors, AC (hazard ratio [HR]: 0.59; p < 0.001), CONUT (HR: 0.82; p = 0.016), GNRI (HR: 0.77; p = 0.040), and PNI (HR: 0.80; p = 0.014) were significant predictors of mortality. However, adding AC to the multivariate-adjusted model (0.739 vs. 0.714, respectively; p = 0.037), but not CONUT, GNRI, or PNI (0.724, 0.717, and 0.723 vs. 0.714; p = 0.072, p = 0.306, and p = 0.127, respectively), significantly increased the area under the curve on receiver operating characteristic curve.

CONCLUSIONS

AC, but not nutritional screening tools, plays a complementary role to preexisting prognostic factors for predicting prognosis in older patients with CVD.

Model-based inverse estimation for active contraction stresses of tongue muscles using 3D surface shape in speech production

This paper presents a novel inverse estimation approach for the active contraction stresses of tongue muscles during speech. The proposed method is based on variational data assimilation using a mechanical tongue model and 3D tongue surface shapes for speech production. The mechanical tongue model considers nonlinear hyperelasticity, finite deformation, actual geometry from computed tomography (CT) images, and anisotropic active contraction by muscle fibers, the orientations of which are ideally determined using anatomical drawings. The tongue deformation is obtained by solving a stationary force-equilibrium equation using a finite element method. An inverse problem is established to find the combination of muscle contraction stresses that minimizes the Euclidean distance of the tongue surfaces between the mechanical analysis and CT results of speech production, where a signed-distance function represents the tongue surface. Our approach is validated through an ideal numerical example and extended to the real-world case of two Japanese vowels, /ʉ/ and /ɯ/. The results capture the target shape completely and provide an excellent estimation of the active contraction stresses in the ideal case, and exhibit similar tendencies as in previous observations and simulations for the actual vowel cases. The present approach can reveal the relative relationship among the muscle contraction stresses in similar utterances with different tongue shapes, and enables the investigation of the coordination of tongue muscles during speech using only the deformed tongue shape obtained from medical images. This will enhance our understanding of speech motor control.

Effects of tongue position in the simplified vocal tract model of Japanese sibilant fricatives /s/ and /ʃ/

The effects of tongue position on sound properties were investigated by using simplified models of sibilant fricatives /s/ and /ʃ/. These were constructed from medical images of a native Japanese-speaking subject who pronounced both fricative sounds. The sounds generated by the models were experimentally measured and compared with the subjects /s/ and /ʃ/. The position of tongue models altered the main peak frequency and spectral mean of the generated sound, which resulted in the reproduction of frequency characteristics of /s/ or /ʃ/ with the subjects tongue position.

Copolymerisation of ethylene with polar monomers by using palladium catalysts bearing an N-heterocyclic carbene–phosphine oxide bidentate ligand

We report the synthesis and characterisation of palladium complexes bearing an N-heterocyclic carbene–phosphine oxide bidentate ligand and their use as catalysts for ethylene polymerisation and ethylene/polar monomer copolymerisation.

The effect of denture installation at mandibular rest position on unsteady motion of the centre of pressure in postural sway

Wearing dentures has been believed to decrease the instability of the postural sway using the total length of centre of pressure (CoP) trajectory or the magnitude of its variability. However, the physical aspects of the postural sway have not been taken into account while evaluating the CoP in patients who wear dentures. The CoP fluctuations are found to show a random walk process. Therefore, changes in the random movement of CoP caused by wearing dentures should be examined by nonlinear dynamics that enables analysis of the characteristics found in the random movement. We evaluated the effect of complete denture installation on CoP sway for twenty-six edentulous patients by performing the following steps. First, we excluded subjects who did not show crossover in spectral analyses. Then, we evaluated the spectral characteristics and phase shifts of the velocities of CoP sway for the subjects who showed crossover. We found that wearing complete dentures decreased the fluctuations in the high-frequency part of the power spectral density (PSD) and the phase shift in the mediolateral direction. On the other hand, we also found that the use of complete dentures decreased the fluctuations of PSD amplitude in the anteroposterior direction. From the point of view of the kinetic energy of the musculoskeletal system, we suggested that the use of complete dentures could reduce the energy consumption for the standing posture.