A comprehensive benchmarking of WGS-based deletion structural variant callers.

Advances in whole-genome sequencing (WGS) promise to enable the accurate and comprehensive structural variant (SV) discovery. Dissecting SVs from WGS data presents a substantial number of challenges and a plethora of SV detection methods have been developed. Currently, evidence that investigators can use to select appropriate SV detection tools is lacking. In this article, we have evaluated the performance of SV detection tools on mouse and human WGS data using a comprehensive polymerase chain reaction-confirmed gold standard set of SVs and the genome-in-a-bottle variant set, respectively. In contrast to the previous benchmarking studies, our gold standard dataset included a complete set of SVs allowing us to report both precision and sensitivity rates of the SV detection methods. Our study investigates the ability of the methods to detect deletions, thus providing an optimistic estimate of SV detection performance as the SV detection methods that fail to detect deletions are likely to miss more complex SVs. We found that SV detection tools varied widely in their performance, with several methods providing a good balance between sensitivity and precision. Additionally, we have determined the SV callers best suited for low- and ultralow-pass sequencing data as well as for different deletion length categories.

Associations of Serum Uric Acid Level With Liver Enzymes, Nonalcoholic Fatty Liver Disease, and Liver Fibrosis in Korean Men and Women: A Cross-Sectional Study Using Nationally Representative Data.

BACKGROUND: This study aimed to determine whether serum uric acid (SUA) levels are associated with various indices of liver damage in the adult Korean population. METHODS: We used the Seventh (VII) Korean National Health and Nutritional Examination Surveys. Our study population comprised 6,007 men and 8,488 women. Levels of SUA were divided into four groups (≤ 5.3, 5.3-6.0, 6.0-7.0, and > 7.0 mg/dL for men and ≤ 4.0, 4.0-4.8, 4.8-6.0, and > 6.0 mg/dL for women). Elevated liver enzyme levels were defined as > 35 (men) and > 31 (women) IU/L for aspartate aminotransferase (AST), > 45 (men) and > 34 (women) IU/L for alanine aminotransferase (ALT). Hepatic steatosis index and fibrosis (FIB)-4 index was used to determine nonalcoholic fatty liver disease (NAFLD) and liver FIB, respectively. Adjusted odds ratios (aORs) were calculated by logistic regression analysis for liver enzymes, NAFLD, and liver FIB, according to the SUA level. RESULTS: Among women, the 4.8-6.0 and > 6.0 mg/dL SUA groups showed higher ORs of elevated AST (aOR, 1.78 and 2.03; 95% confidence interval [CI], 1.37-2.32 and 1.40-2.96, respectively; P < 0.001) and the 4.0-4.8, 4.8-6.0, and > 6.0 mg/dL SUA groups showed a higher ORs of ALT elevation (aOR, 1.35, 2.26, and 2.37; 95% CI, 1.02-1.79, 1.72-2.97, and 1.60-3.50, respectively; P < 0.001) compared to the lowest level SUA group. Among women with normal ALT, > 6.0 mg/dL SUA group showed higher OR of NAFLD status (aOR, 1.52; 95% CI, 1.06-2.19). Among men and women with NAFLD, hyperuricemia showed higher ORs of liver FIB (aOR, 2.25 and 1.89; 95% CI, 1.21-4.19 and 1.09-3.27, respectively) than the lowest level SUA group. CONCLUSION: High SUA levels may be associated with elevated liver enzymes and NAFLD, mainly in women. Even in women with normal ALT levels, SUA levels may predict the NAFLD status. Hyperuricemia may predict advanced liver FIB in both men and women with NAFLD. Further studies investigating the causal effects of SUA on liver damage are required.

Regional Gray Matter Volume Related to High Occupational Stress in Firefighters.

BACKGROUND: Firefighters inevitably encounter emotionally and physically stressful situations at work. Even firefighters without diagnosed post-traumatic stress disorder receive clinical attention because the nature of the profession exposes them to repetitive trauma and high occupational stress. This study investigated gray matter abnormalities related to high occupational stress in firefighters using voxel-based morphometry (VBM) and surface-based morphometry (SBM). METHODS: We assessed 115 subjects (112 males and 3 females) using magnetic resonance imaging and evaluated occupational stress by the Korean Occupational Stress Scale-26 (KOSS-26). Subjects were classified into highly or lowly stressed groups based on the median value of the KOSS-26. RESULTS: In VBM analysis, we found that firefighters with high occupational stress had lower gray matter volume (GMV) in both sides of the insula, the left amygdala, the right medial prefrontal cortex (mPFC), and the anterior cingulate cortex than firefighters with low occupational stress. In SBM analysis based on regions of interest, the GMV of the bilateral insula and right mPFC were also lower in the highly stressed group. Within the highly stressed group, low GMV of the insula was significantly correlated with the length of service (left: r = -0.347, P = 0.009; right: r = -0.333, P = 0.012). CONCLUSION: Our findings suggest that regional GMV abnormalities are related to occupational stress. Regional gray matter abnormalities and related emotional dysregulation may contribute to firefighter susceptibility to burnout.

Robotic Localization Based on Planar Cable Robot and Hall Sensor Array Applied to Magnetic Capsule Endoscope.

Recently an active locomotive capsule endoscope (CE) for diagnosis and treatment in the digestive system has been widely studied. However, real-time localization to achieve precise feedback control and record suspicious positioning in the intestine is still challenging owing to the limitation of capsule size, relatively large diagnostic volume, and compatibility of other devices in clinical site. To address this issue, we present a novel robotic localization sensing methodology based on the kinematics of a planar cable driven parallel robot (CDPR) and measurements of the quasistatic magnetic field of a Hall effect sensor (HES) array. The arrangement of HES and the Levenberg-Marquardt (LM) algorithm are applied to estimate the position of the permanent magnet (PM) in the CE, and the planar CDPR is incorporated to follow the PM in the CE. By tracking control of the planar CDPR, the position of PM in any arbitrary position can be obtained through robot forward kinematics with respect to the global coordinates at the bedside. The experimental results show that the root mean square error (RMSE) for the estimated position value of PM was less than 1.13 mm in the X, Y, and Z directions and less than 1.14° in the θ and φ orientation, where the sensing space could be extended to ±70 mm for the given 34 × 34 mm2 HES array and the average moving distance in the Z-direction is 40 ± 2.42 mm. The proposed method of the robotic sensing with HES and CDPR may advance the sensing space expansion technology by utilizing the provided single sensor module of limited sensible volume.

Multifunctional Nanorobot System for Active Therapeutic Delivery and Synergistic Chemo-photothermal Therapy.

Nanorobots are safe and exhibit powerful functionalities, including delivery, therapy, and diagnosis. Therefore, they are in high demand for the development of new cancer therapies. Although many studies have contributed to the progressive development of the nanorobot system for anticancer drug delivery, these systems still face some critical limitations, such as potentially toxic materials in the nanorobots, unreasonable sizes for passive targeting, and the lack of several essential functions of the nanorobot for anticancer drug delivery including sensing, active targeting, controlling drug release, and sufficient drug loading capacity. Here, we developed a multifunctional nanorobot system capable of precise magnetic control, sufficient drug loading for chemotherapy, light-triggered controlled drug release, light absorption for photothermal therapy, enhanced magnetic resonance imaging, and tumor sensing. The developed nanorobot system exhibits an in vitro synergetic antitumor effect of photothermal therapy and chemotherapy and outstanding tumor-targeting efficiency in both in vitro and in vivo environments. The results of this study encourage further explorations of an efficient active drug delivery system for cancer treatment and the development of nanorobot systems for other biomedical applications.

Observer-Based Deconvolution of Deterministic Input in Coprime Multichannel Systems With Its Application to Noninvasive Central Blood Pressure Monitoring.

Estimating central aortic blood pressure (BP) is important for cardiovascular (CV) health and risk prediction purposes. CV system is a multichannel dynamical system that yields multiple BPs at various body sites in response to central aortic BP. This paper concerns the development and analysis of an observer-based approach to deconvolution of unknown input in a class of coprime multichannel systems applicable to noninvasive estimation of central aortic BP. A multichannel system yields multiple outputs in response to a common input. Hence, the relationship between any pair of two outputs constitutes a hypothetical input-output system with unknown input embedded as a state. The central idea underlying our approach is to derive the unknown input by designing an observer for the hypothetical input-output system. In this paper, we developed an unknown input observer (UIO) for input deconvolution in coprime multichannel systems. We provided a universal design algorithm as well as meaningful physical insights and inherent performance limitations associated with the algorithm. The validity and potential of our approach were illustrated using a case study of estimating central aortic BP waveform from two noninvasively acquired peripheral arterial pulse waveforms. The UIO could reduce the root-mean-squared error (RMSE) associated with the central aortic BP by up to 27.5% and 28.8% against conventional inverse filtering (IF) and peripheral arterial pulse scaling techniques.

Unobtrusive Estimation of Cardiovascular Parameters with Limb Ballistocardiography.

This study investigates the potential of the limb ballistocardiogram (BCG) for unobtrusive estimation of cardiovascular (CV) parameters. In conjunction with the reference CV parameters (including diastolic, pulse, and systolic pressures, stroke volume, cardiac output, and total peripheral resistance), an upper-limb BCG based on an accelerometer embedded in a wearable armband and a lower-limb BCG based on a strain gauge embedded in a weighing scale were instrumented simultaneously with a finger photoplethysmogram (PPG). To standardize the analysis, the more convenient yet unconventional armband BCG was transformed into the more conventional weighing scale BCG (called the synthetic weighing scale BCG) using a signal processing procedure. The characteristic features were extracted from these BCG and PPG waveforms in the form of wave-to-wave time intervals, wave amplitudes, and wave-to-wave amplitudes. Then, the relationship between the characteristic features associated with (i) the weighing scale BCG-PPG pair and (ii) the synthetic weighing scale BCG-PPG pair versus the CV parameters, was analyzed using the multivariate linear regression analysis. The results indicated that each of the CV parameters of interest may be accurately estimated by a combination of as few as two characteristic features in the upper-limb or lower-limb BCG, and also that the characteristic features recruited for the CV parameters were to a large extent relevant according to the physiological mechanism underlying the BCG.

Indirect Force Control of a Cable-Driven Parallel Robot: Tension Estimation using Artificial Neural Network trained by Force Sensor Measurements.

In a cable-driven parallel robot (CDPR), force sensors are utilized at each winch motor to measure the cable tension in order to obtain the force distribution at the robot end-effector. However, because of the effects of friction in the pulleys and the unmodeled cable properties of the robot, the measured cable tensions are often inaccurate, which causes force-control difficulties. To overcome this issue, this paper presents an artificial neural network (ANN)-based indirect end-effector force-estimation method, and its application to CDPR force control. The pulley friction and other unmodeled effects are considered as black-box uncertainties, and the tension at the end-effector is estimated by compensating for these uncertainties using an ANN that is developed using the training datasets from CDPR experiments. The estimated cable tensions at the end-effector are used to design a P-controller to track the desired force. The performance of the proposed ANN model is verified through comparisons with the forces measured directly at the end-effector. Furthermore, cable force control is implemented based on the compensated tensions to evaluate the performance of the CDPR in wrench space. The experimental results show that the proposed friction-compensation method is suitable for application in CDPRs to control the cable force.

Synergistic effects of simvastatin and bone marrow-derived mesenchymal stem cells on hepatic fibrosis.

The beneficial effects of simvastatin on fibrosis in various organs have been reported. In addition, bone marrow (BM)-derived mesenchymal stem cells (MSCs) have been suggested as an effective therapy for hepatic fibrosis and cirrhosis. Recent evidence suggests that pharmacological treatment devoted to regulating stem cell function is a potential new therapeutic strategy that is drawing nearer to clinical practice. The aim of this study was to determine whether the combination treatment of simvastatin plus MSCs (Sim-MSCs) could have a synergistic effect on hepatic fibrosis in a thioacetamide (TAA)-induced cirrhotic rat model and hepatic stellate cells (HSCs). Cirrhotic livers from rats treated with Sim-MSCs exhibited histological improvement compared to those treated with simvastatin alone. Sim-MSCs combination treatment decreased hepatic collagen distribution, lowered the hydroxyproline content, and rescued liver function impairment in rats with TAA-induced cirrhosis. These protective effects were more potent with Sim-MSCs than with simvastatin alone. The upregulation of collagen-1, α-smooth muscle actin (α-SMA), transforming growth factor (TGF)-ß1, and phospho-Smad3 in cirrhotic livers was prevented by the administration of Sim-MSCs. Intriguingly, Sim-MSCs inhibited both TGF-ß/Smad3 signaling and α-SMA in HSCs. The Sim-MSCs combination treatment exerted strong protective effects against hepatic fibrosis by suppressing TGF-ß/Smad signaling. Simvastatin could act synergistically with MSCs as an efficient therapeutic approach for intractable cirrhosis.

Tumor Boost Using External Beam Radiation in Cervical Cancer Patients Unable to Receive Intracavitary Brachytherapy: Outcome From a Multicenter Retrospective Study (Korean Radiation Oncology Group 1419).

PURPOSE: We conducted this study to evaluate the outcomes of external-beam radiotherapy tumor boost (EBRT-B) in cervical cancer patients who could not receive intracavitary brachytherapy. METHODS: A total of 11 hospitals provided the data of patients who received EBRT-B during the period from January 2005 through October 2012. RESULTS: A total of 75 patients were included. The median radiotherapy dose was 46 Gy (range, 40-54 Gy) for whole pelvis and 24 Gy (range, 9-35 Gy) for EBRT-B. Initial tumor responses assessed at 2 to 6 months after radiotherapy were as follows: 46 with complete response, 22 with partial response, 2 with stable disease, and 3 with progressive disease. After a median follow-up time of 33 months, 30 patients (40.0%) showed disease progression including 21 (28.0%) with local progression. The 5-year local failure-free survival rate was 70.0%. Achieving complete response at the first follow-up visit and an overall treatment time of 53 days or less were significantly related to favorable local failure-free survival. The rate of grade 3 or higher toxicity was 2.6%. CONCLUSIONS: Approximately 70% of patients had local tumor control after curative radiotherapy using EBRT-B. Early tumor response and overall treatment time of 53 days or less were closely associated with favorable local control.

Geometric Parameter Calibration for a Cable-Driven Parallel Robot Based on a Single One-Dimensional Laser Distance Sensor Measurement and Experimental Modeling.

A cable-driven parallel robot has benefits of wide workspace, high payload, and high dynamic response owing to its light cable actuator utilization. For wide workspace applications, in particular, the body frame becomes large to cover the wide workspace that causes robot kinematic errors resulting from geometric uncertainty. However, appropriate sensors as well as inexpensive and easy calibration methods to measure the actual robot kinematic parameters are not currently available. Hence, we present a calibration sensor device and an auto-calibration methodology for the over-constrained cable-driven parallel robots using one-dimension laser distance sensors attached to the robot end-effector, to overcome the robot geometric uncertainty and to implement precise robot control. A novel calibration workflow with five phases-preparation, modeling, measuring, identification, and adjustment-is proposed. The proposed calibration algorithms cover the cable-driven parallel robot kinematics, as well as uncertainty modeling such as cable elongation and pulley kinematics. We performed extensive simulations and experiments to verify the performance of the suggested method using the MINI cable robot. The experimental results show that the kinematic parameters can be identified correctly with 0.92 mm accuracy, and the robot position control accuracy is increased by 58%. Finally, we verified that the developed calibration sensor devices and the calibration methodology are applicable to the massive-size cable-driven parallel robot system.

From Visiting a Physician to Expecting Antibiotics: Korean Perspectives and Practices toward Respiratory Tract Infections.

Antibiotic resistance is steadily rising worldwide. Respiratory tract infections (RTIs) are common indications, mostly imprudent, for antibiotic prescriptions in outpatient setting. In Korea, antibiotic prescription rate for RTIs is still high. As physician visit and antibiotic prescribing are influenced by patient's perceptions and beliefs, we aimed to explore the general public's perspectives and practices toward RTIs and to develop the 'RTI clinical iceberg.' A cross-sectional survey was conducted in Wonju Severance Christian Hospital (WSCH) among 550 adults attending outpatient departments during January 2016. Differences in distributions between groups were examined using two-tailed Pearson χ² test. Using the Andersen's behavioral model as a conceptual framework, we constructed logistic regression models to assess factors associated with physician visit. Of 547 participants with complete questionnaires, 62.9% reported having experienced an RTI in the previous six months; 59.3% visited a physician for the illness, most commonly because the symptoms were severe or prolonged, and approximately 16% of them expected an antibiotic prescription from the visit. Perceptions of symptoms severity, the need factor, most strongly influenced physician visit. Predisposing and enabling factors such as inappropriate expectations for antibiotic for a sore throat or having national health insurance also influenced physician visit. Almost all participants who reported asking for an antibiotic were prescribed one, with a 37.1% non-adherence rate. Conclusively, public education on self-care for RTI symptoms that addresses their main concerns may reduce physician visits. Improving physician-patient relationship and informing patients about the lack of antibiotic benefit for most RTIs may also reduce antibiotic prescriptions.

Association of Emotional Labor, Self-efficacy, and Type A Personality with Burnout in Korean Dental Hygienists.

The purpose of this study was to examine the relationship between emotional labor and burnout, and whether the levels of self-efficacy and type A personality characteristics increase the risk of burnout in a sample of Korean female dental hygienists. Participants were 807 female dental hygienists with experience in performing customer service for one year or more in dental clinics, dental hospitals, or general hospitals in Korea. Data were collected using a structured self-administered questionnaire. A hierarchical multiple linear regression analysis was used to examine the effects of emotional labor on burnout, and to elucidate the additive effects of self-efficacy and type A personality on burnout. The results showed that "overload and conflict in customer service," "emotional disharmony and hurt," and "lack of a supportive and protective system in the organization" were positively associated with burnout. With reference to the relationship between personality traits and burnout, we found that personal traits such as self-efficacy and type A personality were significantly related to burnout, which confirmed the additive effects of self-efficacy and type A personality on burnout. These results indicate that engaging in excessive and prolonged emotional work in customer service roles is more likely to increase burnout. Additionally, an insufficient organizational supportive and protective system toward the negative consequences of emotional labor was found to accelerate burnout. The present findings also revealed that personality traits such as self-efficacy and type A personality are also important in understanding the relationship between emotional labor and burnout.

Does High Emotional Demand with Low Job Control Relate to Suicidal Ideation among Service and Sales Workers in Korea?

We examined the relationship of high emotional demands and low job control to suicidal ideation among service and sales workers in Korea. A total of 1,995 service and sales workers participated in this study. Suicidal ideation and level of emotional demand and job control were assessed by self-reported questionnaire in 4th Korean National Health and Nutrition Examination Survey. Gender-specific odds ratio (OR) and 95% confidence intervals (95% CI) for suicidal ideation were calculated using logistic regression analysis. The results show that workers who suffered from high emotional demands (OR, 2.07; 95% CI, 1.24-3.45 in men, OR, 1.97; 95% CI, 1.42-2.75 in women) or low job control (OR, 1.96; 95% CI, 1.42-2.75 in men, OR, 1.33; 95% CI, 0.91-1.93 in women) were more likely to experience suicidal ideation after controlling for age, household income, and employment characteristics. The interaction model of emotional demands and job control revealed that workers with high emotional demands and high job control (OR, 1.93; 95% CI, 1.08-3.45 in men, OR, 1.60; 95% CI,1.06-2.42 in women) and high emotional demands and low job control (OR; 4.60, 95% CI;1.88-11.29 in men, OR; 2.78, 95% CI;1.64-4.44 in women) had a higher risk for suicidal ideation compared to those with low emotional demands and high job control after controlling for age, household income, employment characteristics, smoking, alcohol drinking and physical activity habit. These results suggest that high emotional demands in both genders and low job control in men might play a crucial role in developing suicidal ideation among sales and service workers in Korea.

Facing Complaining Customer and Suppressed Emotion at Worksite Related to Sleep Disturbance in Korea.

This study aimed to investigate the effect of facing complaining customer and suppressed emotion at worksite on sleep disturbance among working population. We enrolled 13,066 paid workers (male = 6,839, female = 6,227, age < 65 years) in the 3rd Korean Working Condition Survey (2011). The odds ratio (OR) and 95% confidence intervals (CI) for sleep disturbance occurrence were calculated using multiple logistic regression models. Among workers in working environments where they always engage complaining customers had a significantly higher risk for sleep disturbance than rarely group (The OR [95% CI]; 5.46 [3.43-8.68] in male, 5.59 [3.30-9.46] in female workers). The OR (95% CI) for sleep disturbance was 1.78 (1.16-2.73) and 1.63 (1.02-2.63), for the male and female groups always suppressing their emotions at the workplace compared with those rarely group. Compared to those who both rarely engaged complaining customers and rarely suppressed their emotions at work, the OR (CI) for sleep disturbance was 9.66 (4.34-20.80) and 10.17 (4.46-22.07), for men and women always exposed to both factors. Sleep disturbance was affected by interactions of both emotional demands (engaging complaining customers and suppressing emotions at the workplace). The level of emotional demand, including engaging complaining customers and suppressing emotions at the workplace is significantly associated with sleep disturbance among Korean working population.

A multicenter analysis of adjuvant therapy after surgery for stage IIIC endometrial adenocarcinoma: A Korean Radiation Oncology Group study (KROG 13-17).

OBJECTIVE: To investigate whether combined chemoradiotherapy (CTRT) confers a benefit for survival outcome over radiotherapy (RT) alone after primary surgery in patients with FIGO stage IIIC endometrial adenocarcinoma. METHODS: We conducted a multicenter retrospective study of patients with surgical stage IIIC endometrial cancer from 1990 to 2011. Adjuvant RT alone was performed in 85 patients (40.3%) and adjuvant CTRT in 126 patients (59.7%). Disease-free survival (DFS) and overall survival (OS) were analyzed using Kaplan-Meier method and Cox proportional hazards model. RESULTS: Stage IIIC1 and stage IIIC2 accounted for 63% and 37%, respectively. FIGO IIIC2 had a higher recurrence rate than FIGO IIIC1 (38.5% vs. 29.3%, p=0.172). Five-year OS and DFS were lower in FIGO IIIC2 than FIGO IIIC1 (85.1% vs. 76.9%, p=0.417; 71.0% vs. 59.2%, p=0.108, respectively). Eighteen patients (13.5%) in stage IIIC1 developed PALN recurrence, whereas only one (3.3%) in stage IIIC2 had PALN recurrence (p=0.001). In multivariate analysis, predictors of DFS were parametrial invasion (HR, 3.49; 95% CI, 1.83-6.64; p<0.001), higher grade (HR, 2.78; 95% CI, 1.31-5.89; p=0.008), and >3 positive pelvic nodes (HR, 1.84; 95% CI, 1.11-3.05; p=0.019). Combined CTRT did not affect DFS or OS in IIIC1 and IIIC2 compared with RT alone. CONCLUSION: CTRT showed comparable survival outcome to RT alone. Half of relapses (46%) in stage IIIC1 occurred in PALN region, whereas relapse in stage IIIC2 primarily occurred in distant metastasis (90%). Future randomized studies are needed to determine which subgroup may be most likely to benefit from CCRT.

Therapeutic Effects of Mesenchymal Stem Cells for Patients with Chronic Liver Diseases: Systematic Review and Meta-analysis.

Based on their ability to differentiate into multiple cell types including hepatocytes, the transplantation of mesenchymal stem cells (MSCs) has been suggested as an effective therapy for chronic liver diseases. The aim of this study was to evaluate the safety, efficacy and therapeutic effects of MSCs in patients with chronic liver disease through a literature-based examination. We performed a systematic review (SR) and meta-analysis (MA) of the literature using the Ovid-MEDLINE, EMBASE and Cochrane Library databases (up to November 2014) to identify clinical studies in which patients with liver diseases were treated with MSC therapy. Of the 568 studies identified by the initial literature search, we analyzed 14 studies and 448 patients based on our selection criteria. None of the studies reported the occurrence of statistically significant adverse events, side effects or complications. The majority of the analyzed studies showed improvements in liver function, ascites and encephalopathy. In particular, an MA showed that MSC therapy improved the total bilirubin level, the serum albumin level and the Model for End-stage Liver Disease (MELD) score after MSC treatment. Based on these results, MSC transplantation is considered to be safe for the treatment of chronic liver disease. However, although MSCs are potential therapeutic agents that may improve liver function, in order to obtain meaningful insights into their clinical efficacy, further robust clinical studies must be conducted to evaluate the clinical outcomes, such as histological improvement, increased survival and reduced liver-related complications, in patients with chronic liver disease.

Data-driven lossy tube-load modeling of arterial tree: in-human study.

In this paper, we present and validate a data-driven method to lossy tube-load modeling of arterial tree in humans. In the proposed method, the lossy tube-load model is fitted to central aortic and peripheral blood pressure (BP) waves in the time domain. For this purpose, we employ a time-domain lossy tube-load model in which the wave propagation constant is formulated to two terms: one responsible for the alteration of wave amplitude and the other for the transport delay. Using the experimental BP data collected from 17 cardiac surgery patients, we showed that the time-domain lossy tube-load model is able to accurately represent the relation between central aortic versus upper-limb and lower-limb BP waves. In addition, the comparison of lossy versus lossless tube-load models revealed that (1) the former outperformed the latter in general with the root-mean-squared errors (RMSE) of 3.1 mm Hg versus 3.5 mm Hg, respectively (p-value < 0.05), and (2) the efficacy of the former over the latter was more clearly observed in case the normalized difference in the mean central aortic versus peripheral BP was large; when the difference was >5% of the underlying mean BP, lossy and lossless models showed the RMSE of 2.7 mm Hg and 3.7 mm Hg, respectively (p-value < 0.05).

The Association between Social Support, Metabolic Syndrome, and Incidence of Cardio-Cerebrovascular Diseases in Older Adults: The ARIRANG Study.

PURPOSE: We investigated the association between social support, metabolic syndrome, and incident cardio-cerebrovascular disease (CCVD) in rural Koreans aged ≥50 years. MATERIALS AND METHODS: We conducted a prospective study using the Korean Genome and Epidemiology Study on Atherosclerosis Risk of Rural Areas in the Korean General Population (KoGES-ARIRANG) dataset. From the baseline of 5169 adults, 1682 participants were finally included according to the exclusion criteria. For outcomes, myocardial infarction, angina, and stroke were included. For independent variables, the social support score and metabolic syndrome were used. Descriptive statistics and multivariate logistic regression were performed to investigate the association among the variables. Paired t-test was conducted to analyze the longitudinal variation of social support scores. RESULTS: During the 6.37 years of median follow-up, 137 participants developed CCVD. The adjusted odds ratio (aOR) of metabolic syndrome with persistently high social support was 2.175 [95% confidence interval (CI): 1.479-3.119]. The aOR of metabolic syndrome with persistently low social support was 2.494 (95% CI: 1.141-5.452). The longitudinal variation of the social support score of persistently high social support group was increased significantly by 4.26±26.32. The score of the persistently low social support group was decreased by 1.34±16.87 with no statistical significance. CONCLUSION: The presence of metabolic syndrome increases the likelihood of developing onset CCVD. Within the metabolic syndrome positive group, when social support was persistently low, the cohort developed more cardio-cerebrovascular disease compared to the persistently higher social support group. The social support score of the persistently low social support group could be improved through proper intervention. To prevent CCVD, metabolic syndrome components and low social support should be improved in the study participants.

Hepatic vein arrival time as assessed by contrast-enhanced ultrasonography is useful for the assessment of portal hypertension in compensated cirrhosis.

The measurement of the hepatic venous pressure gradient (HVPG) for the estimation of portal hypertension (PH) in cirrhosis has some limitations, including its invasiveness. Hepatic vein arrival time (HVAT), as assessed by microbubble contrast-enhanced ultrasonography (CEUS), is negatively correlated with the histological grade of liver fibrosis because of the associated hemodynamic abnormalities. Anatomical and pathophysiological changes in liver microcirculation are the initial events leading to PH. However, the direct relationship between HVAT and PH has not been evaluated. The present study measured both HVPG and HVAT in 71 consecutive patients with compensated cirrhosis and analyzed the relationship between the two parameters (i.e., the derivation set). Results were validated in 35 compensated patients with cirrhosis at another medical center (i.e., the validation set). The derivation set had HVPG and HVAT values of 11.4 ± 5.0 mmHg (mean ± standard deviation; range, 2-23) and 14.1 ± 3.4 seconds (range, 8.4-24.2), respectively; there was a statistically significant negative correlation between HVPG and HVAT (r(2) = 0.545; P < 0.001). The area under the receiver operating characteristic curve (AUROC) was 0.973 for clinically significant PH (CSPH; HVPG, ≥ 10 mmHg), and the sensitivity, specificity, positive predictive value, negative predictive value, and positive and negative likelihood ratios for CSPH for an HVAT cut-off value of 14 seconds were 92.7%, 86.7%, 90.5%, 89.7%, 6.95, and 0.08, respectively. In addition, a shorter HVAT was associated with worse Child-Pugh score (P < 0.001) and esophageal varices (P = 0.018). In the validation set, there was also a significant negative correlation between HVAT and HVPG (r(2) = 0.538; P < 0.001), and AUROC = 0.953 for CSPH. HVAT was significantly correlated with PH. These results indicate that measuring HVAT is useful for the noninvasive prediction of CSPH in patients with compensated cirrhosis.