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1.
Am J Nephrol ; : 1-11, 2024 Aug 17.
Article in English | MEDLINE | ID: mdl-39154635

ABSTRACT

INTRODUCTION: The relationship between fat mass and osteoporosis, sarcopenia, and osteosarcopenia is complex. While higher fat mass generally has a negative impact on bone and muscle health in the general population, the impact in peritoneal dialysis (PD) patients is less well understood. METHODS: In this study of 359 PD patients, sarcopenia was identified using appendicular skeletal muscle per square meter (ASM/m2), with cut-off values of <7.0 kg/m2 for men and <5.5 kg/m2 for women. Fat tissue index (FTI) and lean tissue index (LTI) were determined using body composition monitoring, with the lowest tertile classified as low FTI and low LTI. Bone mineral density was measured, with a T-score below -2.5 indicating osteoporosis. RESULTS: The prevalence of osteoporosis, sarcopenia, and osteosarcopenia was 25%, 32%, and 15%, respectively. Notably, 60% of osteoporotic patients had sarcopenia, and about 45% of sarcopenic patients had osteoporosis. Patients with osteoporosis were older and had significantly lower LTI (15.3 vs. 12.7 kg/m2, p < 0.001) and ASM (7.3 vs. 5.8 kg/m2, p < 0.001). Osteoporotic patients also had lower FTI, but this was more pronounced in men than in women. Patients with both sarcopenia and osteoporosis had the lowest LTI and FTI compared to those with only one or neither condition. Low FTI was a significant determinant for osteoporosis (OR, 2.34; 95% CI, 1.43-3.85; p = 0.001), sarcopenia (OR, 2.91; 95% CI, 1.82-4.64; p < 0.001), and osteosarcopenia (OR, 2.34; 95% CI, 1.30-4.24; p = 0.005) in univariate analysis, and these associations remained significant after adjustment for age and body mass index. CONCLUSION: Osteoporosis and sarcopenia are common and interrelated in PD patients. Low fat mass, but not normal/high fat mass, was significantly associated with these conditions, suggesting the importance of maintaining adequate fat mass in PD patients.

2.
J Gastroenterol Hepatol ; 37(8): 1534-1543, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35501296

ABSTRACT

BACKGROUND AND AIM: Association between protonpump inhibitors (PPIs) and osteoporosis, hip fractures has not been fully elucidated. We aimed to evaluate the relationship between PPIs use and the risk of osteoporosis and hip fractures in the databases converted to a common data model (CDM) and to compare the results across the databases. METHODS: This was a population-based, propensity-matched, retrospective cohort study that included patients aged ≥ 50 years who were prescribed with PPIs for over 180 days. We compared the incidence of osteoporosis and hip fractures between new PPI user and new user of other drugs using the Cox proportional hazards model and performed meta-analysis in the electronic health record (EHR) databases. RESULTS: In the Korean National Health Insurance Service (NHIS)-CDM database, long-term PPI users had greater risk of osteoporosis [PPIs vs non-PPIs groups, 28.42/1000 person-years vs 19.29/1000 person-years; hazard ratio (HR), 1.62; 95% confidence interval (CI), 1.22-2.15; P = 0.001]. The meta-analytic results of six EHR databases also showed similar result (pooled HR, 1.57; 95% CI, 1.28-1.92). In the analysis of hip fracture, PPI use was not significantly associated with a hip fracture in the NHIS-CDM database (PPI vs non-PPI groups, 3.09/1000 person-years vs 2.26/1000 person-years; HR, 1.45; 95% CI, 0.74-2.80; P = 0.27). However, in the meta-analysis of four EHR databases, the risk of hip fractures was higher in PPI users (pooled HR, 1.82; 95% CI, 1.04-3.19). CONCLUSIONS: Long-term PPI was significantly associated with osteoporosis; however, the results of hip fractures were inconsistent. Further study based on better data quality may be needed.


Subject(s)
Hip Fractures , Osteoporosis , Cohort Studies , Hip Fractures/chemically induced , Hip Fractures/epidemiology , Humans , Multicenter Studies as Topic , Osteoporosis/chemically induced , Osteoporosis/epidemiology , Proton Pump Inhibitors/adverse effects , Retrospective Studies , Risk Factors
3.
Gut ; 70(11): 2066-2075, 2021 11.
Article in English | MEDLINE | ID: mdl-33975868

ABSTRACT

OBJECTIVE: The association between proton pump inhibitor (PPI) use and gastric cancer related to Helicobacter pylori eradication has not been fully investigated in geographical regions with high risk of gastric cancer. We aimed to evaluate the association between PPIs and gastric cancer in Korea. DESIGN: This study analysed the original and common data model versions of the Korean National Health Insurance Service database from 2002 to 2013. We compared the incidence rates of gastric cancer after 1-year drug exposure, between new users of PPIs and other drugs excluding PPIs, by Cox proportional hazards model. We also analysed the incidence of gastric cancer among PPI users after H. pylori eradication. RESULTS: The analysis included 11 741 patients in matched PPI and non-PPI cohorts after large-scale propensity score matching. During a median follow-up of 4.3 years, PPI use was associated with a 2.37-fold increased incidence of gastric cancer (PPI≥30 days vs non-PPI; 118/51 813 person-years vs 40/49 729 person-years; HR 2.37, 95% CI 1.56 to 3.68, p=0.001). The incidence rates of gastric cancer showed an increasing trend parallel to the duration of PPI use. In H. pylori-eradicated subjects, the incidence of gastric cancer was significantly associated with PPI use over 180 days compared with the non-PPI group (PPI≥180 days vs non-PPI; 30/12 470 person-years vs 9/7814 person-years; HR 2.22, 95% CI 1.05 to 4.67, p=0.036). CONCLUSION: PPI use was associated with gastric cancer, regardless of H. pylori eradication status. Long-term PPIs should be used with caution in high-risk regions for gastric cancer.


Subject(s)
Proton Pump Inhibitors/adverse effects , Stomach Neoplasms/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Databases, Factual , Female , Helicobacter Infections/complications , Helicobacter Infections/drug therapy , Helicobacter pylori , Humans , Incidence , Male , Middle Aged , Propensity Score , Republic of Korea/epidemiology
4.
Am J Nephrol ; 52(6): 479-486, 2021.
Article in English | MEDLINE | ID: mdl-34111865

ABSTRACT

INTRODUCTION: Successful cannulation of an arteriovenous fistula (AVF) is important in patients starting hemodialysis (HD). Metal needles have been used for decades, but the usefulness of plastic cannulae has recently been demonstrated as a new technique. METHODS: This was a prospective, randomized, open-label study of incident HD patients. Eligible patients were randomized into 2 groups in a 1:1 ratio (n = 45/group). Maturation of the AVF was confirmed using Doppler ultrasound prior to first needling, and 2 well-trained nurses implemented the AVF cannulation. The primary endpoint was the initial cannulation failure rate, defined as the failure of successful completion of 3 consecutive dialysis sessions. The secondary endpoints were time for hemostasis at the end of HD, degree of patients' pain, degree of cannulation difficulty felt by the nursing staffs, and achieving optimal HD adequacy. RESULTS: The mean elapsed time from AVF creation to the first cannulation was 48.1 ± 16.7 days. A total of 17 cases of cannulation failure occurred, and the failure risk tended to be higher in the metal needle group than the plastic cannula group (hazard ratio 2.6, 95% confidence interval 0.95-7.41) after adjusting for age, gender, comorbidities, and AVF location. The overall incidence of vessel injury was higher and time for hemostasis was significantly longer in the metal group than the plastic group. The use of plastic cannula was associated with a better HD adequacy compared to a metal needle. However, the patients' pain score (p = 0.004) and nursing staff's cannulation difficulty score (p = 0.084) were higher in the plastic group, emphasizing the great importance of practice using plastic cannulae. CONCLUSION: The vascular outcomes of plastic cannulae were much favorable compared to metal needles in incident HD patients. The use of plastic cannulae could be a new and innovative way to improve the quality of dialysis.


Subject(s)
Cannula , Catheterization, Peripheral/instrumentation , Needles , Renal Dialysis/instrumentation , Aged , Arteriovenous Shunt, Surgical , Blood Vessels/injuries , Cannula/adverse effects , Female , Hemostasis , Humans , Male , Metals , Middle Aged , Needles/adverse effects , Pain, Procedural/etiology , Plastics , Prospective Studies , Time Factors
5.
Clin Immunol ; 210: 108263, 2020 01.
Article in English | MEDLINE | ID: mdl-31629808

ABSTRACT

Dysregulation of innate immunity has been proposed as an important contributing factor for advanced atherosclerosis and resultant high mortality in hemodialysis (HD) patients. To evaluate the long-term prognostic role of in vivo neutrophil extracellular traps (NETs), we measured circulating serum nucleosome, myeloperoxidase (MPO), and DNase I levels in 281 incident HD patients. Circulating nucleosome level was significantly higher in HD patients compared to controls, and it was closely associated with MPO levels, suggesting increased in vivo NETs in uremia. Patients in the nucleosome Q4 group had significantly increased all-cause and adverse CV mortality compared to those in the Q1-3 group even after adjusting traditional risk factors Also, serum DNase I level was significantly higher in HD patients than controls (2.76 ±â€¯1.02 ng/ml and 1.93 ±â€¯0.85 ng/ml), but it had no correlation with NETs. Interestingly, it serves an additive biomarker for predicting poor CV outcomes. The two novel biomarkers might provide an importance independent prognostic significance in incident HD patients.


Subject(s)
Atherosclerosis/diagnosis , Biomarkers/blood , Deoxyribonuclease I/blood , Extracellular Traps/metabolism , Kidney Failure, Chronic/diagnosis , Neutrophils/immunology , Nucleosomes/metabolism , Aged , Aged, 80 and over , Atherosclerosis/mortality , Female , Humans , Kidney Failure, Chronic/mortality , Male , Middle Aged , Peroxidase/blood , Predictive Value of Tests , Prognosis , Renal Dialysis , Survival Analysis
6.
BMC Nephrol ; 21(1): 281, 2020 07 16.
Article in English | MEDLINE | ID: mdl-32677905

ABSTRACT

BACKGROUND: Increased oxidative stress in end-stage renal disease is regarded as one of the important mechanisms in the atherosclerosis and muscle wasting. However, studies examining the clinical significance of oxidative stress by direct measurement of these markers and its association with volume status and sarcopenia are limited. METHODS: A follow-up cross-sectional study was performed in stable hemodialysis (HD) patients and serum protein carbonyl levels were measured as a biomarker of oxidative stress. Additionally, multi-frequency body composition analysis, handgrip strength (HGS) and nutritional assessments were performed at baseline. RESULTS: Eighty-eight patients undergoing HD were included and 30 (34.1%) patients died during a mean follow-up of 5.2 years. The mean patient age was 60.6 ± 13.5 years, and the mean HD duration was 50.8 ± 41.3 months. In total, 16 patients (18.2%) were overhydrated, 49 (55.7%) had low HGS and 36 (40.9%) had low muscle mass. Serum protein carbonyl levels were associated with serum levels of albumin, prealbumin and transferrin, hydration status and low HGS. Overhydration (odds ratio [OR] 7.01, 95% CI 1.77-27.79, p = 0.006), prealbumin (OR 0.91, 95% CI 0.83-0.99, p = 0.030), subjective global assessment (OR 3.52, 95% CI 1.08-11.46, p = 0.037) and sarcopenia (OR 3.41, 95% CI 1.02-11.32, p = 0.046) were significantly related to increased serum protein carbonyl levels. Multivariate analysis showed that the serum levels of protein carbonyl (Hazard ratio [HR] 2.37, 95% CI 1.02-5.55, p = 0.036), albumin (HR 0.17, 95% CI 0.06-0.46, p = 0.003), prealbumin (HR 0.86, 95% CI 0.80-0.92, p = 0.001), overhydration (HR 2.31, 95% CI 1.26-8.71, p = 0.015) and sarcopenia (HR 2.72, 95% CI 1.11-6.63, p = 0.028) were independent determinants of all-cause mortality. CONCLUSIONS: Serum protein carbonyl was significantly associated with overhydration, nutritional status and sarcopenia, and could be a new predictor of mortality in patients undergoing HD.


Subject(s)
Hand Strength , Kidney Failure, Chronic/metabolism , Mortality , Oxidative Stress , Protein Carbonylation , Sarcopenia/metabolism , Serum Albumin/metabolism , Transferrin/metabolism , Water-Electrolyte Imbalance/metabolism , Aged , Body Composition , Cross-Sectional Studies , Female , Follow-Up Studies , Humans , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/therapy , Male , Middle Aged , Nutritional Status , Odds Ratio , Prealbumin/metabolism , Proportional Hazards Models , Renal Dialysis , Sarcopenia/complications , Sarcopenia/physiopathology , Water-Electrolyte Imbalance/complications
7.
J Nanosci Nanotechnol ; 19(10): 6119-6122, 2019 Oct 01.
Article in English | MEDLINE | ID: mdl-31026919

ABSTRACT

High electron mobility transistors (HEMTs) and Schottky barrier diodes (SBDs) based on AlGaN/GaN heterostructure have been widely studied for high-frequency and/or high-power application. Widely distributed substrates for the high performance of RF applications are presently AlGaN/GaN on SiC, and those for high power performance are AlGaN/GaN on Si. Because the thermal conductivity of CVD diamond substrates is as high as 12 W/cm · K, devices on AlGaN/GaN on CVD diamond are one of the excellent alternatives for power and RF applications. In comparison, the thermal conductivity of AlGaN/GaN on SiC is 4.9 W/cm K, and that of AlGaN/GaN on Si is 1.3 W/cm · K. In this work, we report the fabrication of SBD devices with 163.8 mm Schottky channel length. We also compared the thermal properties of the fabricated large scale SBD devices on different substrates.

8.
Clin Immunol ; 197: 189-197, 2018 12.
Article in English | MEDLINE | ID: mdl-30296592

ABSTRACT

In chronic kidney disease (CKD), the number of circulating neutrophils are increased, and this is usually accompanied by an increased basal activation state. However, the possible association between neutrophil extracellular traps (NETs) with vascular complications has not been evaluated. We assessed the relationship between NETs, autophagy and endothelial dysfunction in maintenance hemodialysis (MHD) patients. NET formation, neutrophil elastase (NE) activities, and serum nucleosome levels were measured in MHD (n = 60) and controls (n = 20). Basal NET formation were markedly increased in MHD patient compared to controls. After PMA stimulation, MHD neutrophils showed significantly increased NETs formation response than controls. The degree of NETs was strongly associated with lower flow-mediated dilatation(%) of brachial artery even after adjustment for cardiovascular risk factors and uremic toxins. Moreover, MHD neutrophils showed increased basal autophagy activity. Interestingly, the levels of NETs were markedly augmented after autophagy inhibition, suggesting a protective role of autophagy in excessive NET formation.


Subject(s)
Autophagy , Brachial Artery/physiopathology , Endothelium, Vascular/physiopathology , Extracellular Traps/metabolism , Neutrophils/metabolism , Renal Insufficiency, Chronic/metabolism , Vasodilation/physiology , Adult , Aged , Case-Control Studies , Endothelium, Vascular/drug effects , Extracellular Traps/drug effects , Female , Humans , Leukocyte Elastase , Male , Middle Aged , Neutrophils/drug effects , Nucleosomes/drug effects , Nucleosomes/metabolism , Renal Dialysis , Renal Insufficiency, Chronic/physiopathology , Tetradecanoylphorbol Acetate/pharmacology , Vasodilation/drug effects
9.
Am J Nephrol ; 47(2): 120-129, 2018.
Article in English | MEDLINE | ID: mdl-29471301

ABSTRACT

BACKGROUND: Fluid overload is a major risk factor for mortality in patients undergoing peritoneal dialysis (PD). However, few studies have investigated the effect of chronic exposure to sustained fluid overload on long-term outcomes. METHOD: A total of 284 prevalent PD patients were included in this prospective study. Repeated multifrequency body composition analysis was performed 12 months apart, and 1-year cumulative chronic fluid overload were used to predict all-cause mortality and the risk for transfer to hemodialysis (HD) during the ensuing 15.6 ± 9.1 months. RESULTS: The prevalence of fluid overload was approximately 27%. Interestingly, a substantial number of hypervolemic patients at first test were persistently hypervolemic at their second test. With this, chronic fluid overload was observed in 18.3% (n = 52). Notably, most of chronic fluid overload patients had diabetes (86.5%), and it was accompanied by concomitant changes in peritoneal membrane characteristics, a higher progression rate to high transporter. The risk of transfer to HD increased 2.8 times in patients with chronic fluid overload than in those without. Also, it significantly increased the risk of mortality (p = 0.038). Surprisingly, subgroup analysis found that patients with euvolemic status at follow-up experienced no mortality despite being in a fluid overload state at baseline. CONCLUSIONS: One-year chronic exposure to fluid overload is a strong independent risk factor for transfer to HD and death in prevalent PD patients. Although the fluid status of most PD patients is not easily changed over time, becoming euvolemic during the entire PD treatment period seems to be very important.


Subject(s)
Body Composition , Electric Impedance , Kidney Failure, Chronic/diagnosis , Adult , Aged , Female , Humans , Kidney Failure, Chronic/therapy , Longitudinal Studies , Male , Middle Aged , Peritoneal Dialysis , Prognosis , Prospective Studies
10.
Ann Nutr Metab ; 73(3): 241-249, 2018.
Article in English | MEDLINE | ID: mdl-30227390

ABSTRACT

BACKGROUND: Although higher body mass index (BMI) is associated with better survival in patients undergoing dialysis, BMI is not an adequate obesity indicator. We hypothesized that the fat-to-lean (F/L) mass ratio could be a suitable marker of nutritional status and evaluated its prognostic impact on long-term outcomes in patients undergoing hemodialysis (HD). METHODS: In total, 131 patients undergoing HD were recruited and monitored prospectively for up to 5 years. Body composition was analyzed, and other nutritional and inflammatory parameters were measured. RESULTS: The mean age of the cohort was 60.7 ± 13.6 years, and 65 patients were diabetic. Age, sex, diabetes, comorbidity, and inflammation were associated significantly with the F/L mass ratio. During the follow-up period, 21 patients experienced cardiac events and 22 patients died. Patients with higher F/L mass ratios had significantly higher risks of all-cause death (hazard ratio [HR] 3.61, 95% CI 1.07-12.13; p = 0.038) and cardiac events (HR 3.54, 95% CI 1.05-11.94; p = 0.041) than those with lower F/L mass ratios. CONCLUSIONS: The F/L mass ratio was a useful surrogate marker of nutritional and inflammatory status, and an independent predictor of cardiac events and all-cause mortality, in patients undergoing HD.


Subject(s)
Body Composition , Cardiovascular Diseases/epidemiology , Renal Dialysis/mortality , Aged , Body Mass Index , Cardiovascular Diseases/mortality , Cause of Death , Cohort Studies , Female , Humans , Male , Middle Aged , Nutritional Status , Prospective Studies
11.
Mult Scler ; 22(7): 960-3, 2016 06.
Article in English | MEDLINE | ID: mdl-26480923

ABSTRACT

BACKGROUND: Spinal cord involvement in Behçet's disease is not well studied. OBJECTIVE: To evaluate the clinical, laboratory and magnetic resonance imaging characteristics of spinal cord involvement in Behçet's disease. METHODS: We retrospectively reviewed 10 spinal cord involvements in seven patients with Behçet's disease. RESULTS: The median age of onset for spinal cord involvement was 32 (23-45 years). Two patients showed a secondary progressive course. Cerebrospinal fluid findings revealed mild to moderate pleocytosis and/or elevated protein levels. In eight spinal cord involvements, the lesion was longer than three vertebrae. Serum anti-aquaporin-4 antibody was negative in all four patients tested. CONCLUSIONS: Longitudinally extensive transverse myelitis is a characteristic manifestation of spinal cord involvement in Behçet's disease.


Subject(s)
Behcet Syndrome/complications , Myelitis, Transverse/etiology , Spinal Cord , Adult , Behcet Syndrome/diagnostic imaging , Biomarkers/cerebrospinal fluid , Disability Evaluation , Disease Progression , Female , Humans , Immunosuppressive Agents/therapeutic use , Magnetic Resonance Imaging , Male , Middle Aged , Myelitis, Transverse/cerebrospinal fluid , Myelitis, Transverse/diagnostic imaging , Myelitis, Transverse/drug therapy , Registries , Retrospective Studies , Spinal Cord/diagnostic imaging , Spinal Cord/drug effects , Spinal Cord/metabolism , Treatment Outcome , Young Adult
12.
Sensors (Basel) ; 16(1)2016 Jan 21.
Article in English | MEDLINE | ID: mdl-26805840

ABSTRACT

We have developed a modified optical frequency domain imaging (OFDI) system that performs parallel imaging of three-dimensional (3D) surface profiles by using the space division multiplexing (SDM) method with dual-area swept sourced beams. We have also demonstrated that 3D surface information for two different areas could be well obtained in a same time with only one camera by our method. In this study, double field of views (FOVs) of 11.16 mm × 5.92 mm were achieved within 0.5 s. Height range for each FOV was 460 µm and axial and transverse resolutions were 3.6 and 5.52 µm, respectively.

13.
Muscle Nerve ; 52(2): 216-20, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25470186

ABSTRACT

INTRODUCTION: Predictive factors for myasthenic crisis after transsternal thymectomy have been reported, but little is known about myasthenic crisis after videoscopic thymectomy (MCAVT). METHODS: We investigated 146 myasthenia gravis patients who underwent videoscopic thymectomy. RESULTS: Patients with MCAVT had a lower forced vital capacity (FVC) (2.1 vs. 3.0 L, P < 0.001) than those without. Low-frequency repetitive nerve stimulation showed decremental responses of the orbicularis oculi (47.1% vs. 18.1%, P = 0.001) and nasalis muscles (54.1% vs. 21.4%, P < 0.001), which were more pronounced in patients with MCAVT than those without. According to multivariate analysis, FVC (OR 0.144, 95% confidence interval [CI], 0.044-0.479, P = 0.002) and decremental response of orbicularis oculi (odds ratio, 1.029; 95% CI, 1.001-1.058, P = 0.044) were independently associated with MCAVT. CONCLUSIONS: FVC and decremental response of orbicularis oculi were associated with MCAVT.


Subject(s)
Myasthenia Gravis/diagnosis , Myasthenia Gravis/surgery , Postoperative Complications/diagnosis , Thymectomy/adverse effects , Video-Assisted Surgery/adverse effects , Adolescent , Adult , Female , Humans , Male , Middle Aged , Postoperative Complications/etiology , Predictive Value of Tests , Retrospective Studies , Thymectomy/trends , Video-Assisted Surgery/trends , Young Adult
14.
Sensors (Basel) ; 14(9): 16109-16, 2014 Aug 29.
Article in English | MEDLINE | ID: mdl-25177803

ABSTRACT

A linearized wavelength-swept thermo-optic laser chip was applied to demonstrate a fiber Bragg grating (FBG) sensor interrogation system. A broad tuning range of 11.8 nm was periodically obtained from the laser chip for a sweep rate of 16 Hz. To measure the linear time response of the reflection signal from the FBG sensor, a programmed driving signal was directly applied to the wavelength-swept laser chip. The linear wavelength response of the applied strain was clearly extracted with an R-squared value of 0.99994. To test the feasibility of the system for dynamic measurements, the dynamic strain was successfully interrogated with a repetition rate of 0.2 Hz by using this FBG sensor interrogation system.

15.
Kidney Res Clin Pract ; 43(2): 156-164, 2024 Mar.
Article in English | MEDLINE | ID: mdl-36908201

ABSTRACT

BACKGROUND: Health Insurance Review and Assessment Service's (HIRA) claims data have been used in studies of hemodialysis patients even though information about mortality is not provided in this database. Mortality analysis using HIRA data has been conducted using various operational definitions that have not been validated. This study aimed to validate operational definitions of mortality for maintenance hemodialysis patients that have been used when analyzing the Korean HIRA database. METHODS: This study utilized claims data of the Korean National Health Insurance Service (NHIS) between January 2008 and December 2019. We estimated mortality based on operational definitions applied in previous studies using the HIRA database and compared it with NHIS mortality information to validate accuracy. RESULTS: A total of 128,876 patients who started maintenance hemodialysis between January 2009 and December 2019 were analyzed. The accuracy of estimated mortality was the highest at 96% in the group where mortality was defined as an absence of claims data for 150 days. If the period of no claims data was set to 90 days or less, there was a risk of overestimating the mortality for the entire study period. When it was set to 180 days or more, there was a risk of underestimating the mortality, as the follow-up time was close to the end of the study period. CONCLUSION: When mortality analysis of maintenance hemodialysis patients is performed using HIRA data, it is most accurate to set the operational definition period as the absence of claims data for 150 days.

16.
Cyberpsychol Behav Soc Netw ; 27(7): 507-517, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38775037

ABSTRACT

This research explores the significance of avatar communication in the virtual world, where individuals can create new identities and establish relationships beyond real-world limitations. Avatar users engage in virtual interactions to fulfill their desires, enjoy entertainment, and experience surrogate satisfaction. This study integrates the Expectation Confirmation Model (ECM) and Impression Management Theory (IMT) to investigate the impact of various avatar ego types on communication satisfaction and continued intention to use. Two surveys (n = 600) were administered using South Korean and American samples. The results suggest a significant relationship between expectancy confirmation and perceived usefulness. Specifically, high perceived usefulness leads to increased communication satisfaction. Also, when pre-experience expectancy confirmation is low, it positively affects communication satisfaction. In addition, the study highlights differences between Western and Eastern cultural contexts in avatar ego type's expression. This study contributes to the understanding of virtual interactions, offering theoretical insights through the integration of ECM and IMT. Theoretical and practical implications are discussed.


Subject(s)
Communication , Ego , Humans , Republic of Korea , Female , Male , Adult , United States , Young Adult , Personal Satisfaction , Cross-Cultural Comparison , User-Computer Interface , Virtual Reality , Interpersonal Relations , Avatar
17.
Sci Rep ; 14(1): 22868, 2024 10 01.
Article in English | MEDLINE | ID: mdl-39353972

ABSTRACT

Dyskalemia is a common electrolyte abnormality. Since dyskalemia can cause fatal arrhythmias and cardiac arrest in severe cases, it is crucial to monitor serum potassium (K+) levels on time. We developed deep learning models to detect hyperkalemia (K+ ≥ 5.5 mEq/L) and hypokalemia (K+ < 3.5 mEq/L) from electrocardiograms (ECGs), which are noninvasive and can be quickly measured. The retrospective cohort study was conducted at two hospitals from 2006 to 2020. The training set, validation set, internal testing cohort, and external validation cohort comprised 310,449, 15,828, 23,849, and 130,415 ECG-K+ samples, respectively. Deep learning models demonstrated high diagnostic performance in detecting hyperkalemia (AUROC 0.929, 0.912, 0.887 with sensitivity 0.926, 0.924, 0.907 and specificity 0.706, 0.676, 0.635 for 12-lead, limb-lead, lead I ECGs) and hypokalemia (AUROC 0.925, 0.896, 0.885 with sensitivity 0.912, 0.896, 0.904 and specificity 0.790, 0.734, 0.694) in the internal testing cohort. The group predicted to be positive by the hyperkalemia model showed a lower 30-day survival rate compared to the negative group (p < 0.001), supporting the clinical efficacy of the model. We also compared the importance of ECG segments (P, QRS, and T) on dyskalemia prediction of the model for interpretability. By applying these models in clinical practice, it will be possible to diagnose dyskalemia simply and quickly, thereby contributing to the improvement of patient outcomes.


Subject(s)
Deep Learning , Electrocardiography , Hyperkalemia , Hypokalemia , Humans , Female , Male , Retrospective Studies , Hyperkalemia/diagnosis , Hyperkalemia/blood , Middle Aged , Aged , Hypokalemia/diagnosis , Hypokalemia/blood , Potassium/blood , Algorithms , Adult
18.
J Nanosci Nanotechnol ; 13(10): 7042-5, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24245185

ABSTRACT

AIGaN/GaN nanowire (NW) FETs with a channel width down to -300 nm has been fabricated by "top-down" approach by using electron-beam lithography process. The fabricated AIGaN/GaN NW FETs showed the minimum threshold voltage -3 V, the gate leakage current -10(-10) A/mm, and the maximum transconductance -216 mS/mm, respectively. It has also been demonstrated that the gate controllability of the AIGaN/GaN FETs is improved with decreasing channel width. In the fabricated devices the threshold voltage V(th) for the NW FETs with a width of -300 nm shows a positive shift (deltaV(th) = 2.5 V) with respect to that of the reference FETs. This can be attributed the change in carrier density of the two dimensional electron gas generated at the interface of an AlGaN/GaN.

19.
J Gambl Stud ; 29(2): 269-88, 2013 Jun.
Article in English | MEDLINE | ID: mdl-22477238

ABSTRACT

Given that current television programming contains numerous gambling portrayals, it is imperative to understand whether and to what extent these gambling behaviors in media influence individuals' beliefs, attitudes, and intentions. This study explores an extended model of the theory of reasoned action (TRA) by including gambling media exposure as a distal, mediating and mediated factor in predicting undergraduate students' intentions to gamble in a casino. Findings show that the extended model of TRA clearly indicates that the constructs of gambling media exposure, prior gambling experience, and level of gambling addiction contribute to the prediction of undergraduate students' casino gambling intentions. Theoretical implications of gambling media effects and practical implications for public policy are discussed, and future research directions are outlined.


Subject(s)
Gambling/psychology , Intention , Students/psychology , Adolescent , Adult , Attitude , Female , Humans , Male , Mass Media , Models, Psychological , Psychological Theory , Students/statistics & numerical data , Young Adult
20.
Nutrients ; 15(9)2023 Apr 29.
Article in English | MEDLINE | ID: mdl-37432308

ABSTRACT

Obesity is a common health problem in peritoneal dialysis (PD) patients and causes high serum ferritin levels. However, mixed results have been reported on whether serum ferritin levels affect the prognosis of PD patients. We investigated the effect of increased adiposity on ferritin levels and its association with mortality in 350 well-nourished PD patients. Body composition was measured using a portable whole-body bioimpedance spectroscope, and clinical determinants of high ferritin levels were evaluated. High ferritin levels (≥600 ng/mL) were observed in 63 (18.0%) patients. Patients with high ferritin levels had a significantly higher body fat percentage and a lower lean tissue index than patients with low or normal ferritin levels. During a median follow-up of 30 months, there were 65 deaths. Ferritin ≥ 600 ng/mL was associated with significantly higher all-cause mortality compared with 200-600 ng/mL of ferritin. Multivariate analysis showed that high ferritin levels were significantly associated with a higher percentage of body fat after adjustment for lean tissue index and volume status. High ferritin increased all-cause mortality in PD patients, and increased fat mass was an important determinant of the high ferritin. Our results support that adiposity may lead to an adverse clinical outcome in PD patients.


Subject(s)
Adipose Tissue , Peritoneal Dialysis , Humans , Adiposity , Body Composition , Ferritins , Obesity , Peritoneal Dialysis/adverse effects
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