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1.
Nicotine Tob Res ; 26(4): 484-493, 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-37742212

ABSTRACT

INTRODUCTION: Cigarette smoke increases peripheral white blood cell (WBC) count. However, the dose-dependent association between smoking and C-reactive protein (CRP), an important inflammatory marker, has been reported as inconsistent. AIMS AND METHODS: Here, we evaluated the associations between smoking and CRP using both smoking questionnaires and urine cotinine as exposure markers. The Korea National Health and Nutrition Examination Survey data were used for analyzing the associations. Multiple regression analyses were performed to examine the associations between cigarette smoke exposure, as assessed by questionnaires and urine cotinine, and health effects, as measured by CRP and WBC count, controlling for potential confounders. The confounders, including age, sex, body mass index, blood pressure, cholesterol, glucose, alanine aminotransferase, and uric acid, were selected a priori based on the literature. RESULTS: A total of 11 435 participants were included for analysis. For the exposure-response relationship, the results indicated a significant increase in CRP levels in male smokers compared to male nonsmokers (p = .002), whereas no significant increase was found in female smokers compared to female nonsmokers (p = .680). For the dose-response relationship, a significant positive association was observed between urine cotinine and CRP in male smokers (p = .018), whereas no significant association was found in female smokers (p = .508). WBC count consistently showed significant exposure-response and dose-response relationships in both sexes. CONCLUSIONS: WBC count was found to be a consistent effect marker of cigarette smoke exposure, while the association between CRP level and smoking was inconsistent and varied by sex. The sex-specific response to cigarette smoke exposure warrants further exploration in future studies. IMPLICATIONS: Cigarette smoke exposure is known to increase inflammation and has been thought to increase CRP, a significant inflammation marker. However, recent studies have reported conflicting results regarding the dose-dependent association between cigarette smoke exposure and CRP. This study found that the association between smoking and CRP is inconsistent and varies by sex, showing significant exposure response in men but not in women. Furthermore, the study suggests that WBC count is a more consistent marker for cigarette smoke exposure.


Subject(s)
Cigarette Smoking , Tobacco Smoke Pollution , Humans , Male , Female , C-Reactive Protein/metabolism , Nutrition Surveys , Cigarette Smoking/adverse effects , Cotinine/analysis , Biomarkers , Inflammation , Leukocyte Count , Tobacco Smoke Pollution/adverse effects , Tobacco Smoke Pollution/analysis
2.
Compr Psychiatry ; 129: 152447, 2024 02.
Article in English | MEDLINE | ID: mdl-38134553

ABSTRACT

BACKGROUND: Personalization is considered an important principle in virtual reality (VR) exposure therapy. We aimed to identify whether personalized VR exposure could provoke increased anxiety in patients with panic disorder and agoraphobia as it is considered the first step in successful treatment for anxiety. METHODS: We performed a double-arm, one-day preliminary study among 28 patients with panic disorder and agoraphobia. Three sessions of VR exposure, including a theater, train, and elevator scenario, were conducted in two groups. In the personalized group (n = 14), the brightness and crowd density were customized based on a pre-assessment. In the control group (n = 14), these conditions were fully randomized. Self-reported anxiety, heart rate, skin conductance, and electroencephalography were measured before, during, and after the VR sessions. RESULTS: In the later VR sessions, higher self-reported anxiety levels measured by the Visual Analogue Scale were observed in the personalized exposure group. Increased heart rates during and after the VR sessions were observed in the personalized group. The changes in skin conductance peaks were not significantly different between the groups, but the increase in skin conductance was associated with the participants' perception of presence. The electroencephalogram showed widespread increases in alpha waves in the frontal and temporal areas of the brain in the personalized group than in the control group. CONCLUSION: Personalized VR exposure elicits stronger anxiogenic effects in patients with panic disorder and agoraphobia as suggested by self-report and neurophysiological data. Personalization of VR exposure has the potential for effective behavioral therapy.


Subject(s)
Panic Disorder , Virtual Reality , Humans , Panic Disorder/diagnosis , Panic Disorder/therapy , Agoraphobia/diagnosis , Agoraphobia/therapy , Anxiety/therapy , Anxiety Disorders
3.
Rheumatol Int ; 2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38850324

ABSTRACT

This study analyzed the status of medical information acquisition through social media (SM) and its impact on healthcare utilization among patients with rheumatic diseases (RDs) who visited the rheumatology department of a tertiary hospital. We consecutively evaluated 102 patients with RDs in this single-center cross-sectional survey. Using a face-to-face survey, patients were asked about the sources they used to acquire medical information, factors influencing their visits to tertiary hospitals, and the potential impact of acquiring medical information on RDs through SM. SM refers to YouTube, Facebook, Instagram, Kakao Channel, Naver Band, and X. The mean age was 42.3 years and 39% were female. The most common disease was ankylosing spondylitis (45.1%), followed by rheumatoid arthritis (20.6%). The most frequent method for acquiring medical information regarding RDs, except for rheumatologists, was internet portal sites (47.8%), followed by SM (40.2%). The most important factor influencing the decision to visit a tertiary hospital was medical doctors (51%); only 1% of the patients responded that SM was the most crucial factor in determining their visit. Most patients (77.5%) responded that acquiring medical information through SM would help them manage their diseases. Our data revealed that a substantial proportion of patients with RDs obtained medical information through SM. However, the impact of SM on visiting a tertiary hospital was minimal, suggesting that SM has become a mainstream source of medical information, yet the reliability of SM remains relatively low. Rheumatology societies should establish SM platforms capable of providing high-quality medical information.

4.
Small ; 19(23): e2207511, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36916693

ABSTRACT

The authors report a strategic approach to achieve metallic properties from semiconducting CuFeS colloidal nanocrystal (NC) solids through cation exchange method. An unprecedentedly high electrical conductivity is realized by the efficient generation of charge carriers onto a semiconducting CuS NC template via minimal Fe exchange. An electrical conductivity exceeding 10 500 S cm-1 (13 400 S cm-1 at 2 K) and a sheet resistance of 17 Ω/sq at room temperature, which are among the highest values for solution-processable semiconducting NCs, are achieved successfully from bornite-phase CuFeS NC films possessing 10% Fe atom. The temperature dependence of the corresponding films exhibits pure metallic characteristics. Highly conducting NCs are demonstrated for a thermoelectric layer exhibiting a high power factor over 1.2 mW m-1 K-2 at room temperature, electrical wires for switching on light emitting diods (LEDs), and source-drain electrodes for p- and n-type organic field-effect transistors. Ambient stability, eco-friendly composition, and solution-processability further validate their sustainable and practical applicability. The present study provides a simple but very effective method for significantly increasing charge carrier concentrations in semiconducting colloidal NCs to achieve metallic properties, which is applicable to various optoelectronic devices.

5.
J Korean Med Sci ; 38(34): e271, 2023 Aug 28.
Article in English | MEDLINE | ID: mdl-37644685

ABSTRACT

BACKGROUND: Lead, which is widely used in various industrial settings, is a major health hazard for manufacturing workers. Therefore, control of lead exposure has been implemented in an effort to prevent lead-related health problems. In this study, our aim was to evaluate temporal trends in occupational lead exposure in Korean lead workers using data from monitoring of workplace exposure. METHODS: A nationwide work environment monitoring database, data from a work environment monitoring institution, and data extracted from a review paper were utilized. Different versions of standard industrial classification codes were aligned with the 10th Korean Standard Industrial Classification, which is generally consistent with the 4th revision of the International Standard Industrial Classification. The multiple data sources were combined and temporal trends over the period from 1994-2021 were estimated. In addition, separate estimation of temporal trends in the storage battery manufacturing industry over the period from 1987-2021 was also performed. RESULTS: A total of 444,296 personal airborne lead measurements were used for the estimation process. The temporal trends in occupational exposure to lead declined by -6% annually over the study period. In particular, levels of lead exposure in the storage battery manufacturing industry showed a steeper decline of -12% annually. CONCLUSIONS: Findings of our study showed that occupational exposure to lead declined over the period from 1994 to 2021 in Korea. However, adverse effects of exposure to lead on health should be regarded with caution. The results will be useful in conduct of epidemiological studies examining lead-related effects on health.


Subject(s)
Lead , Occupational Exposure , Workplace , Humans , Asian People , Databases, Factual , Republic of Korea
6.
Cancer ; 128(21): 3888-3896, 2022 11 01.
Article in English | MEDLINE | ID: mdl-36069361

ABSTRACT

BACKGROUND: Although a considerable proportion of patients with cancer receive chemotherapy (CT) or radiotherapy (RT), only a very few patients eventually develop therapy-related myeloid neoplasms (t-MNs). METHODS: To identify subsets of cancer patients who have substantially elevated risk of developing t-MNs. Incidences and risks of t-MNs after contemporary CT or RT in patients newly diagnosed major cancers during 2009-2013 were analyzed. By merging two Korean nationwide health care big data sets, patients were selected and observed on follow-up to until t-MN development or December 2019. RESULTS: Among 250,155 patients, 555 (0.22%) were diagnosed with t-MNs with a standard incidence ratio (SIR) of 3.40 (95% CI, 3.13-3.70). Patients had bone/joint cancers (SIR, 94.25; 95% CI, 50.71-137.80) and a remarkably high SIR for t-MN development. Patients receiving both CT and RT had the highest SIR (4.64; 95% CI, 4.08-5.20), followed by those receiving CT only (SIR, 3.30; 95% CI, 2.89-3.70). Contrarily, RT alone did not increase t-MN risk (SIR, 1.16; 95% CI, 0.76-1.56). More exposure to leukemogenic agents resulted in the higher t-MNs development. CONCLUSIONS: The increased risk of developing acute myeloid leukemia or myelodysplastic syndrome after CT and/or RT was confirmed and subsets with substantially elevated risk for developing t-MNs were found. Such patients would be suitable for a prospective cohort for investigating t-MN pathogenesis by time series analyses.


Subject(s)
Leukemia, Myeloid, Acute , Myelodysplastic Syndromes , Neoplasms, Second Primary , Neoplasms , Humans , Incidence , Leukemia, Myeloid, Acute/chemically induced , Leukemia, Myeloid, Acute/complications , Leukemia, Myeloid, Acute/epidemiology , Myelodysplastic Syndromes/chemically induced , Myelodysplastic Syndromes/epidemiology , Neoplasms/complications , Neoplasms, Second Primary/epidemiology , Neoplasms, Second Primary/etiology , Prospective Studies , Republic of Korea/epidemiology
7.
Multivariate Behav Res ; 57(4): 543-560, 2022.
Article in English | MEDLINE | ID: mdl-33523709

ABSTRACT

Applications of component-based models have gained much attention as a means of accompanying dimension reduction in the regression setting and have been successfully implemented to model a univariate outcome in the behavioral and social sciences. Despite the prevalence of correlated ordinal outcome data in the fields, however, most of the extant component-based models have been extended to address the multivariate ordinal issue with a simplified but unrealistic assumption of independence, which may lead to biased statistical inferences. Thus, we propose a Bayesian methodology for a component-based model that accounts for unstructured residual covariances, while regressing multivariate ordinal outcomes on pre-defined sets of predictors. The proposed Bayesian multivariate ordinal logistic model re-expresses ordinal outcomes of interest with a set of latent continuous variables based on an approximate multivariate t-distribution. This contributes not only to developing an efficient Gibbs sampler, a Markov Chain Monte Carlo algorithm, but also to facilitating the interpretation of regression coefficients as log-transformed odds ratio. The empirical utility of the proposed method is demonstrated through analyzing a subset of data, extracted from the 2009 to 2010 Health Behavior in School-Aged Children study that investigates risk factors of four different forms of bullying perpetration and victimization: physical, social, racial, and cyber.


Subject(s)
Algorithms , Bayes Theorem , Child , Humans , Logistic Models , Markov Chains , Monte Carlo Method
8.
Sensors (Basel) ; 22(2)2022 Jan 13.
Article in English | MEDLINE | ID: mdl-35062562

ABSTRACT

The present study was performed to investigate the validity of a wireless earbud-type inertial measurement unit (Ear-IMU) sensor used to estimate head angle during four workouts. In addition, relationships between head angle obtained from the Ear-IMU sensor and the angles of other joints determined with a 3D motion analysis system were investigated. The study population consisted of 20 active volunteers. The Ear-IMU sensor measured the head angle, while a 3D motion analysis system simultaneously measured the angles of the head, trunk, pelvis, hips, and knees during workouts. Comparison with the head angle measured using the 3D motion analysis system indicated that the validity of the Ear-IMU sensor was very strong or moderate in the sagittal and frontal planes. In addition, the trunk angle in the frontal plane showed a fair correlation with the head angle determined with the Ear-IMU sensor during a single-leg squat, reverse lunge, and standing hip abduction; the correlation was poor in the sagittal plane. Our results indicated that the Ear-IMU sensor can be used to directly estimate head motion and indirectly estimate trunk motion.


Subject(s)
Torso , Wearable Electronic Devices , Biomechanical Phenomena , Humans , Knee Joint , Pelvis
9.
Molecules ; 27(19)2022 Oct 02.
Article in English | MEDLINE | ID: mdl-36235052

ABSTRACT

Target protein degradation has emerged as a promising strategy for the discovery of novel therapeutics during the last decade. Proteolysis-targeting chimera (PROTAC) harnesses a cellular ubiquitin-dependent proteolysis system for the efficient degradation of a protein of interest. PROTAC consists of a target protein ligand and an E3 ligase ligand so that it enables the target protein degradation owing to the induced proximity with ubiquitin ligases. Although a great number of PROTACs has been developed so far using previously reported ligands of proteins for their degradation, E3 ligase ligands have been mostly limited to either CRBN or VHL ligands. Those PROTACs showed their limitation due to the cell type specific expression of E3 ligases and recently reported resistance toward PROTACs with CRBN ligands or VHL ligands. To overcome these hurdles, the discovery of various E3 ligase ligands has been spotlighted to improve the current PROTAC technology. This review focuses on currently reported E3 ligase ligands and their application in the development of PROTACs.


Subject(s)
Ubiquitin-Protein Ligases , Ubiquitin , Ligands , Proteins/metabolism , Proteolysis , Ubiquitin/metabolism , Ubiquitin-Protein Ligases/metabolism
10.
Eur Radiol ; 31(12): 9664-9674, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34089072

ABSTRACT

OBJECTIVE: Assess if deep learning-based artificial intelligence (AI) algorithm improves reader performance for lung cancer detection on chest X-rays (CXRs). METHODS: This reader study included 173 images from cancer-positive patients (n = 98) and 346 images from cancer-negative patients (n = 196) selected from National Lung Screening Trial (NLST). Eight readers, including three radiology residents, and five board-certified radiologists, participated in the observer performance test. AI algorithm provided image-level probability of pulmonary nodule or mass on CXRs and a heatmap of detected lesions. Reader performance was compared with AUC, sensitivity, specificity, false-positives per image (FPPI), and rates of chest CT recommendations. RESULTS: With AI, the average sensitivity of readers for the detection of visible lung cancer increased for residents, but was similar for radiologists compared to that without AI (0.61 [95% CI, 0.55-0.67] vs. 0.72 [95% CI, 0.66-0.77], p = 0.016 for residents, and 0.76 [95% CI, 0.72-0.81] vs. 0.76 [95% CI, 0.72-0.81, p = 1.00 for radiologists), while false-positive findings per image (FPPI) was similar for residents, but decreased for radiologists (0.15 [95% CI, 0.11-0.18] vs. 0.12 [95% CI, 0.09-0.16], p = 0.13 for residents, and 0.24 [95% CI, 0.20-0.29] vs. 0.17 [95% CI, 0.13-0.20], p < 0.001 for radiologists). With AI, the average rate of chest CT recommendation in patients positive for visible cancer increased for residents, but was similar for radiologists (54.7% [95% CI, 48.2-61.2%] vs. 70.2% [95% CI, 64.2-76.2%], p < 0.001 for residents and 72.5% [95% CI, 68.0-77.1%] vs. 73.9% [95% CI, 69.4-78.3%], p = 0.68 for radiologists), while that in cancer-negative patients was similar for residents, but decreased for radiologists (11.2% [95% CI, 9.6-13.1%] vs. 9.8% [95% CI, 8.0-11.6%], p = 0.32 for residents and 16.4% [95% CI, 14.7-18.2%] vs. 11.7% [95% CI, 10.2-13.3%], p < 0.001 for radiologists). CONCLUSIONS: AI algorithm can enhance the performance of readers for the detection of lung cancers on chest radiographs when used as second reader. KEY POINTS: • Reader study in the NLST dataset shows that AI algorithm had sensitivity benefit for residents and specificity benefit for radiologists for the detection of visible lung cancer. • With AI, radiology residents were able to recommend more chest CT examinations (54.7% vs 70.2%, p < 0.001) for patients with visible lung cancer. • With AI, radiologists recommended significantly less proportion of unnecessary chest CT examinations (16.4% vs. 11.7%, p < 0.001) in cancer-negative patients.


Subject(s)
Artificial Intelligence , Lung Neoplasms , Algorithms , Humans , Lung , Lung Neoplasms/diagnostic imaging , Radiographic Image Interpretation, Computer-Assisted , Radiography , Radiography, Thoracic , Sensitivity and Specificity
11.
Molecules ; 26(15)2021 Jul 26.
Article in English | MEDLINE | ID: mdl-34361643

ABSTRACT

(1) Background: Household humidifier disinfectant (HD) brands containing polyhexamethylene guanidine (PHMG) have been found to cause the most HD-associated lung injuries (HDLIs) in the Republic of Korea. Nevertheless, no study has attempted to characterize the potential association of the health effects, including HDLI, with the physicochemical properties of PHMG dissolved in different HD brands. This study aimed to characterize the molecular weight (MW) distribution, the number-average molecular weight (Mn), the weight-average molecular weight (Mw), and the structural types of PHMG used in HD products. (2) Methods: Quantitative measurements were made using matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS). The Mn, Mw, and MW distributions were compared among various HD products. (3) Results: The mean Mn and Mw were 542.4 g/mol (range: 403.0-692.2 g/mol) and 560.7 g/mol (range: 424.0-714.70 g/mol), respectively. The degree of PHMG oligomerization ranged from 3 to 7. The MW distribution of PHMG indicated oligomeric compounds regardless of the HD brands. (4) Conclusions: Based on the molecular weight distribution, the average molecular weight of PHMG, and the degree of polymerization, the PHMG collected from HDLI victims could be regarded as an oligomer. PHMG, as used in household humidifiers, should not be exempted from toxic chemical registration as a polymer. Further study is necessary to examine the association of PHMG oligomeric compounds and respiratory health effects, including HDLI.


Subject(s)
Disinfectants/chemistry , Guanidines/chemistry , Humidifiers , Lung Injury/chemically induced , Humans , Molecular Weight , Polymerization , Republic of Korea
12.
Calcif Tissue Int ; 106(2): 124-130, 2020 02.
Article in English | MEDLINE | ID: mdl-31642952

ABSTRACT

Although body composition is related to lung function, few studies have reported the effects of sarcopenic obesity on lung function. Thus, the aim of this study was to investigate the associations between lung function and sarcopenia in the presence and in the absence of obesity. We analyzed nationally representative data of 3044 adults aged > 60 years as collated by the 'Korean National Health and Nutrition Examination Survey 2014-2016. Subjects were classified into four groups: non-sarcopenic non-obese (S-O-), non-sarcopenic obese (S-O+), sarcopenic non-obese (S+O-), and sarcopenic obese (S+O+) according to handgrip strength (GS) and body mass index (BMI). GS was found to be positively associated with forced volume vital capacity (FVC). The S+O+ group had significantly lower FVC values than the S-O- group. Subjects in the S+O+ group were more likely to have restrictive lung disease than those in the S-O- group (odds ratios [ORs] 2.81, 95% confidence interval [CI] 1.72-4.59), and the ORs of restrictive lung disease in S+O+ group were higher than in the S-O+ or S+O- groups. These results were consistent after stratifying by sex and age (61-70 and 71-80). FEV1/FVC ratios (a marker for obstructive lung disease) were not significantly different between S+O+ and S-O- groups. Sarcopenic obesity is associated with a higher risk of restrictive lung disease in Korean elderly.


Subject(s)
Aging/physiology , Lung/physiopathology , Obesity/physiopathology , Sarcopenia/physiopathology , Aged , Aged, 80 and over , Body Mass Index , Female , Hand Strength/physiology , Humans , Male , Middle Aged , Muscle, Skeletal/physiopathology , Nutrition Surveys , Obesity/complications , Obesity/epidemiology , Prevalence , Republic of Korea/epidemiology , Respiratory Function Tests , Sarcopenia/complications , Sarcopenia/epidemiology
13.
Biotechnol Bioeng ; 117(9): 2897-2910, 2020 09.
Article in English | MEDLINE | ID: mdl-32510167

ABSTRACT

Core binding factor ß (Cbfß) is a non-DNA binding cofactor of Runx2 that potentiates DNA binding. Previously, it has been reported that Cbfß plays an essential role in osteogenic differentiation and skeletal development by inhibition adipogenesis. Here, we delivered the recombinant Cbfß protein into human mesenchymal stem cells (MSCs) and triggered osteogenic lineage commitment. The efficient delivery of Cbfß was achieved by fusing 30Kc19 protein, which is a cell-penetrating protein derived from the silkworm. After the production of the recombinant Cbfß-30Kc19 protein in the Escherichia coli expression system, and confirmation of its intracellular delivery, MSCs were treated with the Cbfß-30Kc19 once or twice up to 300 µg/ml. By investigating the upregulation of osteoblast-specific genes and phenotypical changes, such as calcium mineralization, we demonstrated that Cbfß-30Kc19 efficiently induced osteogenic differentiation in MSCs. At the same time, Cbfß-30Kc19 suppressed adipocyte formation and downregulated the expression of adipocyte-specific genes. Our results demonstrate that the intracellularly delivered Cbfß-30Kc19 enhances osteogenesis in MSCs, whereas it suppresses adipogenesis by altering the transcriptional regulatory network involved in osteoblast-adipocyte lineage commitment. Cbfß-30Kc19 holds great potential for the treatment of bone-related diseases, such as osteoporosis, by allowing transcriptional regulation in MSCs, and overcoming the limitations of current therapies.


Subject(s)
Cell Differentiation/drug effects , Core Binding Factor beta Subunit , Mesenchymal Stem Cells/drug effects , Osteogenesis/drug effects , Recombinant Fusion Proteins , Adipocytes/drug effects , Cell-Penetrating Peptides/genetics , Cells, Cultured , Core Binding Factor beta Subunit/genetics , Core Binding Factor beta Subunit/pharmacokinetics , Core Binding Factor beta Subunit/pharmacology , Gene Expression Regulation/drug effects , Humans , Intracellular Space/metabolism , Osteoblasts/drug effects , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/pharmacokinetics , Recombinant Fusion Proteins/pharmacology
14.
Inorg Chem ; 59(21): 15717-15723, 2020 Nov 02.
Article in English | MEDLINE | ID: mdl-33035048

ABSTRACT

We synthesized CsBr nanoplatelets and controlled their size and shape using HBr and tetrabutylammonium bromide (TBAB) as bromine precursors, obtaining hexagonal and rectangular plates, respectively. The phenomena were elucidated by density functional theory calculations, which indicated that the formation of the hexagonal shape was explained by comparing the relaxed surface free energy of oleate on the exposable surfaces of the CsBr plates. As the bromine precursor changed from HBr to TBAB, the formation of the rectangular shape was determined by comparing the surface free energy and attachment free energy between exposable surfaces due to its bulky surfactant tail. In addition, the TEM measurements indicated that the rectangles or hexagonal shapes are aligned precisely regardless of their size. The data mean that the large plates split into smaller plates as the temperature increases so that the nanoplatelets were formed by a top-down method in which a large plate was split by surfactants rather than through a bottom-up method in which a rectangle or a hexagon grew from smaller particles. The facts were explained by the surface chemical thermodynamics model which showed that the surface area (σ) and the crystal size decreased as the temperature increased.

15.
Multivariate Behav Res ; 55(1): 30-48, 2020.
Article in English | MEDLINE | ID: mdl-31021267

ABSTRACT

Extended redundancy analysis (ERA) combines linear regression with dimension reduction to explore the directional relationships between multiple sets of predictors and outcome variables in a parsimonious manner. It aims to extract a component from each set of predictors in such a way that it accounts for the maximum variance of outcome variables. In this article, we extend ERA into the Bayesian framework, called Bayesian ERA (BERA). The advantages of BERA are threefold. First, BERA enables to make statistical inferences based on samples drawn from the joint posterior distribution of parameters obtained from a Markov chain Monte Carlo algorithm. As such, it does not necessitate any resampling method, which is on the other hand required for (frequentist's) ordinary ERA to test the statistical significance of parameter estimates. Second, it formally incorporates relevant information obtained from previous research into analyses by specifying informative power prior distributions. Third, BERA handles missing data by implementing multiple imputation using a Markov Chain Monte Carlo algorithm, avoiding the potential bias of parameter estimates due to missing data. We assess the performance of BERA through simulation studies and apply BERA to real data regarding academic achievement.


Subject(s)
Bayes Theorem , Behavioral Research/methods , Biostatistics/methods , Data Interpretation, Statistical , Markov Chains , Models, Statistical , Monte Carlo Method , Humans
16.
Int J Mol Sci ; 21(1)2020 Jan 05.
Article in English | MEDLINE | ID: mdl-31948013

ABSTRACT

Stem cells secrete numerous paracrine factors, such as cytokines, growth factors, and extracellular vesicles. As a kind of extracellular vesicle (EV), exosomes produced in the endosomal compartment of eukaryotic cells have recently emerged as a biomedical material for regenerative medicine, because they contain many valuable contents that are derived from the host cells, and can stably deliver those contents to other recipient cells. Although we have previously demonstrated the beneficial effects of human induced potent stem cell-derived exosomes (iPSC-Exo) on the aging of skin fibroblasts, low production yield has remained an obstacle for clinical applications. In this study, we generated cell-engineered nanovesicles (CENVs) by serial extrusion of human iPSCs through membrane filters with diminishing pore sizes, and explored whether the iPSC-CENV ameliorates physiological alterations of human dermal fibroblasts (HDFs) that occur by natural senescence. The iPSC-CENV exhibited similar characteristics to the iPSC-Exo, while the production yield was drastically increased compared to that of iPSC-derived EVs, including exosomes. The proliferation and migration of both young and senescent HDFs were stimulated by the treatment with iPSC-CENVs. In addition, it was revealed that the iPSC-CNEV restored senescence-related alterations of gene expression. Treatment with iPSC-CENVs significantly reduced the activity of senescence-associated-ß-galactosidase (SA-ß-Gal) in senescent HDFs, as well as suppressing the elevated expression of p53 and p21, key factors involved in cell cycle arrest, apoptosis, and cellular senescence signaling pathways. Taken together, these results suggest that iPSC-CENV could provide an excellent alternative to iPSC-exo, and be exploited as a resource for the treatment of signs of skin aging.


Subject(s)
Cellular Senescence/drug effects , Exosomes/metabolism , Fibroblasts/metabolism , Induced Pluripotent Stem Cells/metabolism , Nanoparticles/metabolism , Cell Engineering , Cell Movement/drug effects , Cell Proliferation/drug effects , Cells, Cultured , Cellular Senescence/genetics , Cyclin-Dependent Kinase Inhibitor p21/genetics , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Fibroblasts/drug effects , Humans , Microscopy, Electron, Transmission , Nanoparticles/therapeutic use , Nanoparticles/ultrastructure , Skin Aging/drug effects , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism
17.
Molecules ; 25(14)2020 Jul 21.
Article in English | MEDLINE | ID: mdl-32708129

ABSTRACT

The use of humidifier disinfectant (HD) has been determined to be associated with lung injuries (HDLI) in Korea. Although HD brands containing polyhexamethylene guanidine (PHMG) oligomers have been found to cause more HDLI compared to brands containing other disinfectants, the physicochemical properties of PHMG have been poorly defined. We aimed to quantify the PHMG dissolved in HD brands, characterize the number-average (Mn) and weight-average (Mw) molecular masses, and identify the polymerization degree of PHMG. Analysis of the PHMG oligomers was performed using a matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI-TOF MS) operated in positive-ion reflectron mode. Eight brands of HD containing PHMG were identified. The PHMG concentrations in these brands ranged from 160 to 37,200 ppm (mean = 3100.9 ppm). Concentration was a significant variable among and within HD brands. The degree of PHMG oligomerization fell within the range of two to four. The averages of Mn and Mw were 517.2 g/mol (range: 422-613 g/mol) and 537.3 g/mol (range: 441.0-678.0 g/mol), respectively. Based on the average molecular weight and the degree of polymerization, the PHMG examined here could be regarded as oligomers, which may be associated with the highest proportion of HDLI being caused by PHMG.


Subject(s)
Disinfectants/analysis , Guanidines/analysis , Lung Injury/etiology , Lung Injury/prevention & control , Equipment Contamination/prevention & control , Humans , Humidifiers , Lung , Molecular Weight , Polymerization , Republic of Korea , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
18.
Molecules ; 25(22)2020 Nov 12.
Article in English | MEDLINE | ID: mdl-33198358

ABSTRACT

This study aimed to quantify both chloromethylisothiazolinone (CMIT) and methylisothiazolinone (MIT) dissolved in different product brands and to characterize the exposure to these chemicals among humidifier disinfectant-associated lung injury (HDLI) patients. Both CMIT and MIT dissolved in different humidifier disinfectant (HD) products were quantified using gas chromatography-mass spectrometry. The inhalation level of CMIT and MIT was estimated based on HD-associated factors as reported by HDLI patients. A total of eleven HD products marketed until the end of 2011 were found to contain CMIT and/or MIT. The level of combined CMIT and/or MIT dissolved in these HD products ranged from 12 to 353 ppm. The level varied among HD products and the year of manufacture. The average inhalation levels were estimated to be 7.5, 4.1, and 3.2 µg/m3 for the definite, probable, and possible groups, respectively. If probable and possible groups were collapsed together, the inhalation level of the collapsed group was significantly different from that of the definite group (p < 0.001). All HDLI patients responded as having used HD not only while sleeping, but also as having a humidifier treated with HD within close proximity every day in insufficiently ventilated spaces. These HD use characteristics of patients may be directly/indirectly linked to the HDLI development.


Subject(s)
Humidifiers , Lung Injury/chemically induced , Lung/drug effects , Thiazoles/adverse effects , Adult , Air Pollutants/adverse effects , Child , Child, Preschool , Disinfectants/adverse effects , Female , Gas Chromatography-Mass Spectrometry , Humans , Infant , Inhalation Exposure , Limit of Detection , Male , Middle Aged , Republic of Korea
19.
Small ; 15(43): e1904031, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31496116

ABSTRACT

Uniform Ag nanocubes are reproducibly synthesized by a AgCl particle-mediated heterogeneous nucleation and disassembly process in polyol chemistry. By introducing N,N-dimethylformamide (DMF) in a conventional polyol method with HCl etchant, Ag nanocrystals (NCs) begin to be nucleated on the surface of AgCl-precipitated particles due to the promoted reduction reaction by DMF. The nucleated Ag NCs on the AgCl particles are grown to Ag nanocubes in shape by consuming Ag sources from the AgCl mother particles. Eventually the grown Ag nanocubes are disassembled from the mother AgCl particles because the AgCl particles are fully digested by the growing Ag nanocubes. Density functional theory calculation confirms that the Ag atoms can be favorably deposited on the (100) facet of AgCl particles and the Ag nuclei on the AgCl particles tend to reveal (100) facet.

20.
Nat Mater ; 17(6): 504-508, 2018 06.
Article in English | MEDLINE | ID: mdl-29713039

ABSTRACT

Time reversal and spatial inversion are two key symmetries for conventional Bardeen-Cooper-Schrieffer (BCS) superconductivity 1 . Breaking inversion symmetry can lead to mixed-parity Cooper pairing and unconventional superconducting properties1-5. Two-dimensional (2D) NbSe2 has emerged as a new non-centrosymmetric superconductor with the unique out-of-plane or Ising spin-orbit coupling (SOC)6-9. Here we report the observation of an unusual continuous paramagnetic-limited superconductor-normal metal transition in 2D NbSe2. Using tunelling spectroscopy under high in-plane magnetic fields, we observe a continuous closing of the superconducting gap at the upper critical field at low temperatures, in stark contrast to the abrupt first-order transition observed in BCS thin-film superconductors10-12. The paramagnetic-limited continuous transition arises from a large spin susceptibility of the superconducting phase due to the Ising SOC. The result is further supported by self-consistent mean-field calculations based on the ab initio band structure of 2D NbSe2. Our findings establish 2D NbSe2 as a promising platform to explore novel spin-dependent superconducting phenomena and device concepts 1 , such as equal-spin Andreev reflection 13 and topological superconductivity14-16.

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