Publications by authors named "Jieun Yang"

39 Publications

TPRG1-AS1 induces RBM24 expression and inhibits liver cancer progression by sponging miR-4691-5p and miR-3659.

Liver Int 2021 Jul 30. Epub 2021 Jul 30.

Department of Physiology, Ajou University School of Medicine, Suwon, Republic of Korea.

Background & Aims: Noncoding RNAs (ncRNAs) play critical roles in hepatocellular carcinoma (HCC) progression. Here, by performing RNA-sequencing (RNA-Seq) profiling, we sought to identify novel ncRNAs that potentially drive the heterogeneous progression of liver cancers.

Methods: RNA-Seq profiles were obtained from 68 HCC specimens and 10 samples of adjacent non-tumour liver tissues. The functional significance of the potential driver ncRNAs was evaluated by cell experiments.

Results: TPRG1-AS1 was identified as a potential driver noncoding RNA that promotes heterogeneous liver cancer progression. TPRG1-AS1 induced tumour suppressor RNA-binding motif protein 24 (RBM24), suppressing tumour growth by activating apoptotic tumour cell death. In addition, we report that TPRG1-AS1 acts as a competing endogenous RNA (ceRNA) for RBM24, sponging miR-4691-5p and miR-3659 to interfere with their binding to RBM24.

Conclusions: We suggest that TPRG1-AS1 is a novel ceRNA sponging miR-4691-5p and miR-3659, resulting in RBM24 expression and suppression of liver cancer growth. Our results provide new insights into the functions of ncRNAs in heterogeneous HCC progression.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/liv.15026DOI Listing
July 2021

USO1 isoforms differentially promote liver cancer progression by dysregulating the ER-Golgi network.

Carcinogenesis 2021 Jul 22. Epub 2021 Jul 22.

Department of Physiology, Ajou University School of Medicine, Suwon, Republic of Korea.

Alternative splicing of RNA transcripts plays an important role in cancer development and progression. Recent advances in RNA-seq technology have made it possible to identify alternately spliced events in various types of cancer; however, research on hepatocellular carcinoma (HCC) is still limited. Here, by performing RNA-Seq profiling of HCC transcripts at isoform level, we identified tumor-specific and molecular subtype-dependent expression of the USO1 isoforms, which we designated as a normal form USO1-N (XM_001290049) and a tumor form USO1-T (NM_003715). The expression of USO1-T, but not USO1-N, was associated with worse prognostic outcomes of HCC patients. We confirmed that the expression of USO1-T promoted an aggressive phenotype of HCC, both in vitro and in vivo. In addition, structural modeling analyses revealed that USO1-T lacks an ARM10 loop encoded by exon 15, which may weaken the dimerization of USO1 and its tethering to GM130. We demonstrated that USO1-T ensured unstacking of the Golgi and accelerated the trafficking from ER to Golgi and plasma membrane in multiple liver cancer cells. ERK and GRASP65 were found to be involved in the USO1-T mediated Golgi dysfunction. Conclusively, we provide new mechanophysical insights into the USO1 isoforms that differentially regulate the ER-Golgi network, promoting the heterogeneous HCC progression.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/carcin/bgab067DOI Listing
July 2021

A Photovoice Study: The life experiences of middle-aged adults with intellectual disabilities in Korea.

J Appl Res Intellect Disabil 2021 May 8;34(3):852-865. Epub 2021 Mar 8.

Woori Daycare Center, Gyeonggi, Republic of Korea.

Background: As adults with intellectual disabilities approach older adulthood, they face unique physical and psychosocial challenges. This study explored the lived experiences of middle-aged adults with intellectual disabilities living in their community.

Method: Six sessions of Photovoice were conducted with a purposeful sample of six middle-aged adults with intellectual disabilities in South Korea. Participants were involved with the theme selection, taking photographs related to the themes, group discussion of photo stories and sharing Photovoice outcomes.

Results: Thematic analysis yielded 11 subthemes under the five major themes selected by the participants: health, free time, time in the centre, family and my future in old age.

Conclusions: The study findings showed complex issues middle-aged adults with intellectual disabilities may face in later life, including bereavement and healthy lifestyle concerns. It is important to create a space for meaningful social support and social interactions without stigma.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/jar.12870DOI Listing
May 2021

Synthesis of metallic mixed 3R and 2H NbS nanoflakes by chemical vapor deposition.

Faraday Discuss 2021 Apr 1;227:332-340. Epub 2021 Feb 1.

Institute of Microengineering and Nanoelectronics, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Malaysia.

In this work, we report the synthesis and characterization of mixed phase NbS nanoflakes prepared by chemical vapor deposition. The as-grown samples show a high density of flakes (thickness ∼50 nm) that form a continuous film. Raman and X-ray diffraction data show that the samples consist of both 2H and 3R phases, with the 2H phase containing a high concentration of Nb interstitials. These Nb interstitials sit in between the NbS layers to form NbS. Cross-sectional Energy Dispersive Spectroscopy analysis with transmission electron microscopy suggests that the 2H NbS region is found in thinner flakes, while 3R NbS is observed in thicker regions of the films. The evolution of the phase from 2H NbS to 3R NbS may be attributed to the change of the growth environment from Nb-rich at the start of the growth to sulfur-rich at the latter stage. It was also found that the incorporation of Nb interstitials is highly dependent on the temperature of the NbCl precursor and the position of the substrate in the furnace. Samples grown at high NbCl temperature and with substrate located closer to the NbCl source show higher incorporation of Nb interstitials. Electrical measurements show linear I-V characteristics, indicating the metallic nature of the NbS film with relatively low resistivity of 4.1 × 10Ω cm.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1039/c9fd00132hDOI Listing
April 2021

Sex-Biased Molecular Signature for Overall Survival of Liver Cancer Patients.

Biomol Ther (Seoul) 2020 Nov;28(6):491-502

Duksung Innovative Drug Center, College of Pharmacy, Duksung Women's University, Seoul 01369, Republic of Korea.

Sex/gender disparity has been shown in the incidence and prognosis of many types of diseases, probably due to differences in genes, physiological conditions such as hormones, and lifestyle between the sexes. The mortality and survival rates of many cancers, especially liver cancer, differ between men and women. Due to the pronounced sex/gender disparity, considering sex/ gender may be necessary for the diagnosis and treatment of liver cancer. By analyzing research articles through a PubMed literature search, the present review identified 12 genes which showed practical relevance to cancer and sex disparities. Among the 12 sex-specific genes, 7 genes (, , , , , , and ) showed sex-biased function in liver cancer. Here we summarized previous findings of cancer molecular signature including our own analysis, and showed that sexbiased molecular signature , , and may serve as a female-specific index for prediction and evaluation of OS in liver cancer patients. This review suggests a potential implication of sex-biased molecular signature in liver cancer, providing a useful information on diagnosis and prediction of disease progression based on gender.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4062/biomolther.2020.157DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7585639PMC
November 2020

Evidence of Rotational Fröhlich Coupling in Polaronic Trions.

Phys Rev Lett 2020 Aug;125(8):086803

NUSNNI NanoCore, National University of Singapore, Singapore 117411.

Electrons commonly couple through Fröhlich interactions with longitudinal optical phonons to form polarons. However, trions possess a finite angular momentum and should therefore couple instead to rotational optical phonons. This creates a polaronic trion whose binding energy is determined by the crystallographic orientation of the lattice. Here, we demonstrate theoretically within the Fröhlich approach and experimentally by photoluminescence emission that the bare trion binding energy (20 meV) is significantly enhanced by the phonons at the interface between the two-dimensional semiconductor MoS_{2} and the bulk transition metal oxide SrTiO_{3}. The low-temperature binding energy changes from 60 meV in [001]-oriented substrates to 90 meV for [111] orientation, as a result of the counterintuitive interplay between the rotational axis of the MoS_{2} trion and that of the SrTiO_{3} phonon mode.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1103/PhysRevLett.125.086803DOI Listing
August 2020

Ultrahigh-current-density niobium disulfide catalysts for hydrogen evolution.

Nat Mater 2019 12 26;18(12):1309-1314. Epub 2019 Aug 26.

Materials Science and Engineering, Rutgers University, Piscataway, NJ, USA.

Metallic transition metal dichalcogenides (TMDs) are good catalysts for the hydrogen evolution reaction (HER). The overpotential and Tafel slope values of metallic phases and edges of two-dimensional (2D) TMDs approach those of Pt. However, the overall current density of 2D TMD catalysts remains orders of magnitude lower (~10-100 mA cm) than industrial Pt and Ir electrolysers (>1,000 mA cm). Here, we report the synthesis of the metallic 2H phase of niobium disulfide with additional niobium (2H NbS, where x is ~0.35) as a HER catalyst with current densities of >5,000 mA cm at ~420 mV versus a reversible hydrogen electrode. We find the exchange current density at 0 V for 2H NbS to be ~0.8 mA cm, corresponding to a turnover frequency of ~0.2 s. We demonstrate an electrolyser based on a 2H NbS cathode that can generate current densities of 1,000 mA cm. Our theoretical results reveal that 2H NbS with Nb-terminated surface has free energy for hydrogen adsorption that is close to thermoneutral, facilitating HER. Therefore, 2H NbS could be a viable catalyst for practical electrolysers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41563-019-0463-8DOI Listing
December 2019

Single Atomic Vacancy Catalysis.

ACS Nano 2019 Sep 14;13(9):9958-9964. Epub 2019 Aug 14.

Materials Science and Metallurgy , University of Cambridge , 27 Charles Babbage Road , Cambridge CB3 0FS , United Kingdom.

Single atom catalysts provide exceptional activity. However, measuring the intrinsic catalytic activity of a single atom in real electrochemical environments is challenging. Here, we report the activity of a single vacancy for electrocatalytically evolving hydrogen in two-dimensional (2D) MoS. Surprisingly, we find that the catalytic activity per vacancy is not constant but increases with its concentration, reaching a sudden peak in activity at 5.7 × 10 cm where the intrinsic turn over frequency and Tafel slope of a single atomic vacancy was found to be ∼5 s and 44 mV/dec, respectively. At this vacancy concentration, we also find a local strain of ∼3% and a semiconductor to metal transition in 2D MoS. Our results suggest that, along with increasing the number of active sites, engineering the local strain and electrical conductivity of catalysts is essential in increasing their activity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsnano.9b05226DOI Listing
September 2019

Volatile Flavor Components as a Function of Electrical Stimulation and Chiller Aging for and of Hanwoo Beef.

Food Sci Anim Resour 2019 Jun 30;39(3):474-493. Epub 2019 Jun 30.

Department of Animal Science, Chonbuk National University, Jeonju 54896, Korea.

The aim of the study was to evaluate the effect of an early post-mortem low voltage electrical stimulation (ES) to localized part of carcasses [ (LL) and (BF)] and determined the tenderness and flavor compounds of Hanwoo steers (n=16). Carcasses were stimulated within 30 min post-mortem for 60s using 60 volts and muscles aged 2 and 14 d. Degradation of Troponin-T were accelerated by ES and degraded little faster in BF muscle than LL. Level of free amino acid content of stimulated and aged muscles was significantly (p<0.05) greater than control for both muscles. Totally 63 volatile compounds were identified by using SPME-GC. The ES treatment significantly (p<0.05) affected the level of 20 volatile compounds of LL as well 15 volatiles in BF muscle along with total amounts of ketones, sulfur containing, pyrazines and furans. Low voltage ES could be applied to reduce the aging time and improve volatile flavor development by increasing important desirable volatile compounds such as 2-methylpyrazine, 2,5-dimethylpyrazines and 2-acetylthiazole etc. due to released free amino acids from protein degradation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5851/kosfa.2019.e43DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6612794PMC
June 2019

Plasmon-Free Surface-Enhanced Raman Spectroscopy Using Metallic 2D Materials.

ACS Nano 2019 Jul 11;13(7):8312-8319. Epub 2019 Jul 11.

International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education , Shenzhen University , Shenzhen 518060 , P.R. China.

Two dimensional (2D) materials-based plasmon-free surface-enhanced Raman scattering (SERS) is an emerging field in nondestructive analysis. However, impeded by the low density of state (DOS), an inferior detection sensitivity is frequently encountered due to the low enhancement factor of most 2D materials. Metallic transition-metal dichalcogenides (TMDs) could be ideal plasmon-free SERS substrates because of their abundant DOS near the Fermi level. However, the absence of controllable synthesis of metallic 2D TMDs has hindered their study as SERS substrates. Here, we realize controllable synthesis of ultrathin metallic 2D niobium disulfide (NbS) (<2.5 nm) with large domain size (>160 μm). We have explored the SERS performance of as-obtained NbS, which shows a detection limit down to 10 mol·L. The enhancement mechanism was studied in depth by density functional theory, which suggested a strong correlation between the SERS performance and DOS near the Fermi level. NbS features the most abundant DOS and strongest binding energy with probe molecules as compared with other 2D materials such as graphene, 1T-phase MoS, and 2H-phase MoS. The large DOS increases the intermolecular charge transfer probability and thus induces prominent Raman enhancement. To extend the results to practical applications, the resulting NbS-based plasmon-free SERS substrates were applied for distinguishing different types of red wines.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsnano.9b03761DOI Listing
July 2019

Role of Sulfur Vacancies and Undercoordinated Mo Regions in MoS Nanosheets toward the Evolution of Hydrogen.

ACS Nano 2019 Jun 7;13(6):6824-6834. Epub 2019 Jun 7.

Institut Européen des Membranes, IEM, UMR 5635 , Université Montpellier , ENSCM, CNRS, 34095 Montpellier Cedex 5, France.

Low-dimensional materials have been examined as electrocatalysts for the hydrogen evolution reaction (HER). Among them, two-dimensional transition metal dichalcogenides (2D-TMDs) such as MoS have been identified as potential candidates. However, the performance of TMDs toward HER in both acidic and basic media remains inferior to that of noble metals such as Pt and its alloys. This calls for investigating the influence of controlled defect engineering of 2D TMDs on their performance toward hydrogen production. Here, we explored the HER activity from defective multilayered MoS over a large range of surface S vacancy concentrations up to 90%. Amorphous MoS and 2H MoS with ultrarich S vacancies demonstrated the highest HER performance in acid and basic electrolytes, respectively. We also report that the HER performance from multilayered MoS can be divided into two domains corresponding to "point defects" at low concentrations of surface S vacancies (Stage 1) and large regions of undercoordinated Mo atoms for high concentrations of surface S vacancies (Stage 2). The highest performance is obtained for Stage 2 in the presence of undercoordinated Mo atoms with a TOF of ∼2 s at an overpotential of 160 mV in 0.1 M KOH which compares favorably to the best results in the literature. Overall, our work provides deeper insight on the HER mechanism from defected MoS and provides guidance for the development of defect-engineered TMD-based electrocatalysts.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsnano.9b01583DOI Listing
June 2019

Van der Waals contacts between three-dimensional metals and two-dimensional semiconductors.

Nature 2019 04 27;568(7750):70-74. Epub 2019 Mar 27.

Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, UK.

As the dimensions of the semiconducting channels in field-effect transistors decrease, the contact resistance of the metal-semiconductor interface at the source and drain electrodes increases, dominating the performance of devices. Two-dimensional (2D) transition-metal dichalcogenides such as molybdenum disulfide (MoS) have been demonstrated to be excellent semiconductors for ultrathin field-effect transistors. However, unusually high contact resistance has been observed across the interface between the metal and the 2D transition-metal dichalcogenide. Recent studies have shown that van der Waals contacts formed by transferred graphene and metals on few-layered transition-metal dichalcogenides produce good contact properties. However, van der Waals contacts between a three-dimensional metal and a monolayer 2D transition-metal dichalcogenide have yet to be demonstrated. Here we report the realization of ultraclean van der Waals contacts between 10-nanometre-thick indium metal capped with 100-nanometre-thick gold electrodes and monolayer MoS. Using scanning transmission electron microscopy imaging, we show that the indium and gold layers form a solid solution after annealing at 200 degrees Celsius and that the interface between the gold-capped indium and the MoS is atomically sharp with no detectable chemical interaction between the metal and the 2D transition-metal dichalcogenide, suggesting van-der-Waals-type bonding between the gold-capped indium and monolayer MoS. The contact resistance of the indium/gold electrodes is 3,000 ± 300 ohm micrometres for monolayer MoS and 800 ± 200 ohm micrometres for few-layered MoS. These values are among the lowest observed for three-dimensional metal electrodes evaporated onto MoS, enabling high-performance field-effect transistors with a mobility of 167 ± 20 square centimetres per volt per second. We also demonstrate a low contact resistance of 220 ± 50 ohm micrometres on ultrathin niobium disulfide (NbS) and near-ideal band offsets, indicative of defect-free interfaces, in tungsten disulfide (WS) and tungsten diselenide (WSe) contacted with indium alloy. Our work provides a simple method of making ultraclean van der Waals contacts using standard laboratory technology on monolayer 2D semiconductors.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41586-019-1052-3DOI Listing
April 2019

Management of Chronic Disease and Hospitalization Due to Diabetes among Type 2 Diabetes Patients in Korea: Using the National Sample Cohort Data 2002⁻2013.

Int J Environ Res Public Health 2018 11 13;15(11). Epub 2018 Nov 13.

Institute of Health Services Research, Yonsei University, Seoul 03722, Korea.

To prevent negative outcomes for diabetes patients, developing self-management skills is imperative. This study aimed to examine the association between management of chronic disease (MCD), which mainly involves educating patients about their chronic diseases for obtaining self-management skills and hospitalization due to diabetes among type 2 diabetes patients in Korea. Korean National Health Insurance Service National Sample Cohort data from 2002 to 2013 were used. A total of 54,031 type 2 diabetes patients were included in the study. If patients received the MCD within 1 year from the onset of diabetes, we categorized them as "MCD received patients" We reclassified these groups into five groups: "non-receiving", "1⁻3 times", "4⁻6 times", "7⁻9 times" and "10⁻12 times" The dependent variable of this study was hospitalization due to diabetes. Cox proportional hazard regression was used. Of the patients, 86.2% (n = 46,571) did not received the MCD within the 1 year from the onset of diabetes. The number of MCDs received increased and the hazard ratio (HR) for hospitalization due to diabetes decreased; particularly, patients who received MCD 10⁻12 times per annum showed the lowest HR for hospitalization due to diabetes compared to patients in the MCD non-received group (1⁻3 times per annum: HR: 0.81, = 0.0001; 4⁻6 times per annum: HR: 0.82, = 0.0248; 7⁻9 times per annum: HR: 0.75, = 0.0054; 10⁻12 times per annum: HR: 0.61, < 0.0001). Considering the importance of raising self-managing diabetes skills, the findings can aid in determining the outcomes of the MCD program.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijerph15112541DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6266696PMC
November 2018

The Association between Social Contacts and Depressive Symptoms among Elderly Koreans.

Psychiatry Investig 2018 Sep 6;15(9):861-868. Epub 2018 Sep 6.

Institute of Health Services Research, Yonsei University, Seoul, Republic of Korea.

Objective: South Korea has an increasing aging population; thus, the management of depressive symptoms in elderly individuals is important. In this population, fewer social contacts might be a risk factor for depressive symptoms. We examined associations between the frequency of social contacts and depressive symptoms among elderly Koreans and factors associated with these symptoms.

Methods: Data from 62,845 individuals over 65 years of age enrolled in the 2015 Community Health Survey were used in this study. Logistic regression was performed to test the association between depressive symptoms and social contacts.

Results: Individuals who had contact with neighbors less than once a week were more likely to experience depressive symptoms [odds ratio (OR): 1.22, 95% confidence interval (CI): 1.10-1.35] compared to those who had contact more than once a week. Individuals who had frequent contact with neighbors and friends, neighbors and relatives, or all three groups were significantly less likely to experience depressive symptoms.

Conclusion: The frequency of social contact with neighbors was the most powerful factor associated with elderly adults' depressive symptoms among other social relationships. Additional senior welfare centers may facilitate the ability of elderly individuals in meeting neighbors, thereby reducing the risk of depressive symptoms.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.30773/pi.2018.06.28.1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6166029PMC
September 2018

Effect of the Calpain System on Volatile Flavor Compounds in the Beef Muscle.

Korean J Food Sci Anim Resour 2018 Jul 31;38(3):515-529. Epub 2018 Jul 31.

Department of Animal Science, Chonbuk National University, Jeonju 28644, Korea.

The present study was designed to investigate the effects of calpain system on the formation of volatile flavor compounds in Hanwoo beef. In the first experiment (, (LL) muscle samples were injected with solutions containing 50 mM CaCl or 50 mM ZnCl and 154 mM NaCl respectively, and aged for 7 d at 4°C. In the second experiment (, the ground LL muscle was incubated with the aforementioned solutions containing cathepsin inhibitor. The injection with CaCl solution greatly elevated the calpain activity and concomitantly, significantly decreased the Warner-Bratzler shear force (<0.05). The pH, meat color and cooking loss did not differ (>0.05) between the treatment groups. A total of 51 volatile compounds were identified using the solid phase microextraction with gas chromatography (SPME-GC). Results on volatile analyses from the both experiments showed that the injection with calcium ions led to significant increase (<0.05) concentrations of pyrazines and sulfuric compounds. These results coincide with a higher rate of protein degradation due to the CaCl injection as compared to the control group. Significantly (<0.05) higher levels of lipid oxidation derived-aldehydes were found in the samples with ZnCl. The showed that cathepsin inhibitors had no effect on the formation of volatile flavor components after 7 d of aging. These results imply that the proteolytic activity of the calpain system is associated with generation of volatile compounds of chiller-aged beef, while the role of cathepsins is likely very limited.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5851/kosfa.2018.38.3.515DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6048373PMC
July 2018

Associations Between Hand Hygiene Education and Self-Reported Hand-Washing Behaviors Among Korean Adults During MERS-CoV Outbreak.

Health Educ Behav 2019 02 16;46(1):157-164. Epub 2018 Jul 16.

1 Yonsei University, Seoul, Republic of Korea.

Background: Hand washing is an effective way to prevent transmission of infectious diseases. Education and promotional materials about hand washing may change individuals' awareness toward hand washing. Infectious disease outbreak may also affect individuals' awareness.

Aims: Our study aimed to examine associations between hand-washing education and self-reported hand-washing behaviors among Korean adults during the year of the Middle East respiratory syndrome (MERS) outbreak.

Methods: Data from the 2015 Community Health Survey were used for this study. The total study population comprised 222,599 individuals who were older than 20 years of age. A multiple linear regression model was used to investigate associations between hand hygiene education and self-reported hand-washing behaviors. Subgroup analyses stratified by age, sex, income, and MERS outbreak regions were also performed.

Results: Individuals who received hand-washing education or saw promotional materials related to hand washing had significantly higher scores for self-reported use of soap or sanitizer (β = 0.177, P < .0001) and self-reported frequency of hand washing (β = 0.481, P < .0001) than those who did not have such experiences. The effect of hand-washing education on self-reported behavior change was greater among older adults, women, and lower income earners. The effect of hand hygiene education on self-reported use of soap or sanitizer was similar regardless of whether the participants lived in MERS regions.

Conclusion: Our findings emphasize the importance of education or promotions encouraging hand washing, especially for older adults, women, and lower income earners. In addition, MERS outbreak itself affected individuals' awareness of hand-washing behaviors. Well-organized campaigns that consider these factors are needed to prevent infectious diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/1090198118783829DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7207011PMC
February 2019

Preparation of Chiral Contiguous Epoxyaziridines and Their Regioselective Ring-Opening for Drug Syntheses.

Chemistry 2018 Feb 25;24(10):2370-2374. Epub 2018 Jan 25.

Department of Energy Science, Sungkyunkwan University, Suwon, 16419, South Korea.

Synthetically valuable chiral (aziridin-2-yl)oxirane-3-carbaldehydes bearing three consecutive functional groups including aziridine, epoxide, and aldehyde were prepared from the stereoselective epoxidation of (aziridin-2-yl)acrylaldehydes with H O using organocatalyst (2R)- or (2S)-[diphenyl(trimethylsilyloxy)methyl]pyrrolidine as organocatalyst. The regioselective ring opening of aziridines and epoxides enabled us to achieve the highly efficient asymmetric synthesis of the antibiotic edeine D fragment 3-hydroxy-4,5-diaminopenatanoic acid, an intermediate for the formal synthesis of non-proteinogenic amino acid (-)-galantinic acid, and for potent antifungal agent (+)-preussin, and the medicinally important framework 3-hydroxy-2-hydroxymethylpyrrolidine.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/chem.201706161DOI Listing
February 2018

Synthesis and reduction of large sized graphene oxide sheets.

Chem Soc Rev 2017 Nov;46(23):7306-7316

Department of Chemistry and Center for Advanced 2D Materials, National University of Singapore, 3 Science Drive 3, 117543, Singapore.

Graphene oxide (GO) can be considered as one of the most visible outcomes of graphene research in terms of large scale production and commercialization prospects. Although GO can be easily prepared by oxidation-exfoliation of graphite in agitated solutions, the size of these sheets is generally limited due to fragmentation along fault lines during chemical oxidation and exfoliation in agitated solutions. In this account, we discuss recent strategies which have been developed for the preparation of large sized graphene oxide (LGO) sheets with lateral sizes >10 μm, using chemically expanded graphite as the starting material. LGO has a much lower density of defects than GO prepared using the conventional Hummers' method and can be readily transformed into graphene by chemical reduction. In addition, the unique advantages of using LGO sheets as a performance enhancer are discussed. Finally, this review also discusses recent advances in the chemical and electrochemical reduction of graphene oxide.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1039/c7cs00485kDOI Listing
November 2017

Selective synthesis of pure cobalt disulfide on reduced graphene oxide sheets and its high electrocatalytic activity for hydrogen evolution reaction.

Nano Converg 2016 27;3(1). Epub 2016 Jan 27.

Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), UNIST-gil 50, Ulsan, 689-798 Republic of Korea.

We synthesized single-phase CoS on a large scale by adding graphene oxide of sufficient quantity via the hydrothermal method using cobalt acetate and thioacetamide as precursors; this produced the hybrid of CoS with reduced graphene oxide which exhibited high electrocatalytic activity in the hydrogen evolution reaction.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s40580-016-0066-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5271118PMC
January 2016

Solution-Processed MoS /Organolead Trihalide Perovskite Photodetectors.

Adv Mater 2017 Jan 21;29(4). Epub 2016 Nov 21.

Materials Science and Engineering, Rutgers University, 607 Taylor Road, Piscataway, NJ, 08854, USA.

Integration of organic/inorganic hybrid perovskites with metallic or semiconducting phases of 2D MoS nanosheets via solution processing is demonstrated. The results show that the collection of charge carriers is strongly dependent on the electronic properties of the 2D MoS with metallic MoS showing high responsivity and the semiconducting phase exhibiting high on/off ratios.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/adma.201603995DOI Listing
January 2017

High-quality graphene via microwave reduction of solution-exfoliated graphene oxide.

Science 2016 09 1;353(6306):1413-1416. Epub 2016 Sep 1.

Materials Science and Engineering, Rutgers University, 607 Taylor Road, Piscataway, NJ 08854, USA.

Efficient exfoliation of graphite in solutions to obtain high-quality graphene flakes is desirable for printable electronics, catalysis, energy storage, and composites. Graphite oxide with large lateral dimensions has an exfoliation yield of ~100%, but it has not been possible to completely remove the oxygen functional groups so that the reduced form of graphene oxide (GO; reduced form: rGO) remains a highly disordered material. Here we report a simple, rapid method to reduce GO into pristine graphene using 1- to 2-second pulses of microwaves. The desirable structural properties are translated into mobility values of >1000 square centimeters per volt per second in field-effect transistors with microwave-reduced GO (MW-rGO) as the channel material and into particularly high activity for MW-rGO catalyst support toward oxygen evolution reactions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1126/science.aah3398DOI Listing
September 2016

Eating Quality Traits of Hanwoo longissimus dorsi Muscle as a Function of End-Point Cooking Temperature.

Korean J Food Sci Anim Resour 2016 30;36(3):291-9. Epub 2016 Jun 30.

Department of Animal Science and Biotechnology, Chonbuk National University, Jeonju 54896, Korea.

Interaction between carcass quality grade and end-point cooking temperature on eating quality of Hanwoo m. longissimus was investigated. Ten (10) of steers were sampled from a commercial population; carcasses with QG 1(++) (n=5) and QG 1 (n=5) were chosen. Samples were cooked by electric oven at 60 or 82℃ and compared with uncooked control samples. The pH was not affected by cooking temperature but decreased the redness after cooking and steaks cooked at 60℃ were more reddish than steaks cooked at 82℃ in both QG groups. Higher cooking temperature greatly (p<0.05) increased the cooking loss, but there was no significant interaction between cooking temperature and QG on the cooking loss. Moisture is negatively correlated with temperature in both QG while the proportionate relationship between crude fat and end-point temperature found in QG 1(++). WBSF values were significantly (p<0.05) high for QG 1, while that was significantly (p<0.05) increased when the temperature continues to increase. The increasing quality grade of beef resulted in significant higher (p<0.01) level of TBARS and cooking temperature increased TBARS content. Fatty acid composition was not altered by cooking at both temperatures and also the amount of fat intake was not changed. The current study indicates that eating quality of beef m. longissimus was greatly influenced by end-point temperature being interacted with QG. However, the amount and composition of fat were stable regardless of end-point temperatures. These results will provide a consumer reference to determine cooking conditions and intramuscular fat content.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5851/kosfa.2016.36.3.291DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4942543PMC
July 2016

The role of electronic coupling between substrate and 2D MoS2 nanosheets in electrocatalytic production of hydrogen.

Nat Mater 2016 09 13;15(9):1003-9. Epub 2016 Jun 13.

Materials Science and Engineering, Rutgers University, 607 Taylor Road, Piscataway, New Jersey 08854, USA.

The excellent catalytic activity of metallic MoS2 edges for the hydrogen evolution reaction (HER) has led to substantial efforts towards increasing the edge concentration. The 2H basal plane is less active for the HER because it is less conducting and therefore possesses less efficient charge transfer kinetics. Here we show that the activity of the 2H basal planes of monolayer MoS2 nanosheets can be made comparable to state-of-the-art catalytic properties of metallic edges and the 1T phase by improving the electrical coupling between the substrate and the catalyst so that electron injection from the electrode and transport to the catalyst active site is facilitated. Phase-engineered low-resistance contacts on monolayer 2H-phase MoS2 basal plane lead to higher efficiency of charge injection in the nanosheets so that its intrinsic activity towards the HER can be measured. We demonstrate that onset potentials and Tafel slopes of ∼-0.1 V and ∼50 mV per decade can be achieved from 2H-phase catalysts where only the basal plane is exposed. We show that efficient charge injection and the presence of naturally occurring sulfur vacancies are responsible for the observed increase in catalytic activity of the 2H basal plane. Our results provide new insights into the role of contact resistance and charge transport on the performance of two-dimensional MoS2 nanosheet catalysts for the HER.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/nmat4660DOI Listing
September 2016

Regulatory T Cells Contribute to the Inhibition of Radiation-Induced Acute Lung Inflammation via Bee Venom Phospholipase A₂ in Mice.

Toxins (Basel) 2016 04 30;8(5). Epub 2016 Apr 30.

Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul 130-701, South Korea.

Bee venom has long been used to treat various inflammatory diseases, such as rheumatoid arthritis and multiple sclerosis. Previously, we reported that bee venom phospholipase A₂ (bvPLA₂) has an anti-inflammatory effect through the induction of regulatory T cells. Radiotherapy is a common anti-cancer method, but often causes adverse effects, such as inflammation. This study was conducted to evaluate the protective effects of bvPLA₂ in radiation-induced acute lung inflammation. Mice were focally irradiated with 75 Gy of X-rays in the lung and administered bvPLA₂ six times after radiation. To evaluate the level of inflammation, the number of immune cells, mRNA level of inflammatory cytokine, and histological changes in the lung were measured. BvPLA₂ treatment reduced the accumulation of immune cells, such as macrophages, neutrophils, lymphocytes, and eosinophils. In addition, bvPLA₂ treatment decreased inflammasome-, chemokine-, cytokine- and fibrosis-related genes' mRNA expression. The histological results also demonstrated the attenuating effect of bvPLA₂ on radiation-induced lung inflammation. Furthermore, regulatory T cell depletion abolished the therapeutic effects of bvPLA₂ in radiation-induced pneumonitis, implicating the anti-inflammatory effects of bvPLA₂ are dependent upon regulatory T cells. These results support the therapeutic potential of bvPLA₂ in radiation pneumonitis and fibrosis treatments.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/toxins8050131DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4885046PMC
April 2016

Recent Strategies for Improving the Catalytic Activity of 2D TMD Nanosheets Toward the Hydrogen Evolution Reaction.

Adv Mater 2016 Aug 12;28(29):6197-206. Epub 2016 Feb 12.

Department of Materials Science and Engineering, Rutgers, The State University of New Jersey, NJ, USA.

Two-dimensional (2D) transition-metal dichalcogenide (TMD) nanosheets have emerged as a fascinating new class of materials for catalysis. These nanosheets are active for several important catalysis reactions including hydrogen evolution from water. The rich chemistry of TMDs combined with numerous strategies that allow tuning of their electronic properties make these materials very attractive for understanding the fundamental principles of electro- and photocatalysis, as well as for developing highly efficient, renewable, and affordable catalysts for large-scale production of hydrogen. Recent developments are highlighted and important challenges in using TMDs as catalysts are also discussed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/adma.201505597DOI Listing
August 2016

Dietary intake of fats and fatty acids in the Korean population: Korea National Health and Nutrition Examination Survey, 2013.

Nutr Res Pract 2015 Dec 23;9(6):650-7. Epub 2015 Nov 23.

Department of Food and nutrition, Daejeon University, 62, Daehak-ro, Dong-gu, Daejeon 34520, Korea.

Background/objectives: The aim of this study was to estimate average total fat and fatty acid intakes as well as identify major food sources using data from the Korea National Health and Nutrition Examination Survey (KNHANES) VI-1 (2013).

Subjects/methods: Total fat and fatty acid intakes were estimated using 24-hour dietary recall data on 7,048 participants aged ≥ 3 years from the KNHANES VI-1 (2013). Data included total fat, saturated fatty acid (SFA), monounsaturated fatty acid (MUFA), polyunsaturated fatty acid (PUFA), n-3 fatty acid (n-3 FA), and n-6 fatty acid (n-6 FA) levels. Population means and standard errors of the mean were weighted in order to produce national estimates and separated based on sex, age, income, as well as residential region. Major food sources of fat, SFA, MUFA, PUFA, n-3 FA, and n-6 FA were identified based on mean consumption amounts of fat and fatty acids in each food.

Results: The mean intake of total fat was 48.0 g while mean intakes of SFA, MUFA, PUFA, n-3 FA, and n-6 FA were 14.4 g, 15.3 g, 11.6 g, 1.6 g, and 10.1 g, respectively. Intakes of MUFA and SFA were each higher than that of PUFA in all age groups. Pork was the major source of total fat, SFA, and MUFA, and soybean oil was the major source of PUFA. Milk and pork were major sources of SFA in subjects aged 3-11 years and ≥ 12 years, respectively. Perilla seed oil and soybean oil were main sources of n-3 FA in subjects aged ≥ 50 years and aged < 50 years, respectively.

Conclusions: Estimation of mean fatty acid intakes of this study using nationally represented samples of the Korean population could be useful for developing and evaluating national nutritional policies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4162/nrp.2015.9.6.650DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4667207PMC
December 2015

Electrospun antimicrobial hybrid mats: Innovative packaging material for meat and meat-products.

J Food Sci Technol 2015 Jul 24;52(7):4600-6. Epub 2014 Oct 24.

Department of Animal Sciences and Biotechnology, Chonbuk National University, Jeonju, South Korea.

To prevent the development and spread of spoilage/pathogenic microorganisms via meat foodstuffs, antimicrobial nanocomposite packaging can serve as a potential alternative. The objective of this study was to develop a new class of antimicrobial hybrid packaging mat composed of biodegradable polyurethane supplemented with virgin olive oil and zinc oxide via electrospinning. Instead of mixing antimicrobial compounds directly with food, incorporation in packaging materials allows the functional effect at food surfaces where microbial activity is localized. The nanofibers were characterized by SEM, EDX, XRD and TEM. The antibacterial activity was tested against two common foodborne pathogens viz., Staphylococcus aureus and Salmonella typhimurium. The present results indicated that incorporation of olive oil in the polymer affected morphology of PU nanofibers and nanocomposite packaging were able to inhibit growth of pathogens. Thus; as-spun mat can be used as prospective antimicrobial packaging, which potentially reduces contamination of meat/meat-products. Moreover, introduced biodegradable packaging for meat products could serve to replace PVC films and simultaneously help to protect natural environment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s13197-014-1508-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4486575PMC
July 2015

The standardized Lycium chinense fruit extract protects against Alzheimer's disease in 3xTg-AD mice.

J Ethnopharmacol 2015 Aug 20;172:85-90. Epub 2015 Jun 20.

Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul 130-701, Republic of Korea. Electronic address:

Background: Alzheimer's disease (AD) is the most common cause of dementia. This disease is a progressive and irreversible brain disorder accompanied with severe learning and memory impairment. This study investigated whether treatment with standardized Lycii Fructus Extract (LFE) would improve the cognitive function and the pathological features of AD in 3xTg-AD mice.

Ethnopharmacological Relevance: Lycii Fructus is a fruit of Lycium chinense Miller and widely distributed in East Asia and has been used traditionally for anti-aging purposes.

Materials And Methods: The cognitive function of 3xTg-AD mice was assessed using the Morris water maze test. The levels of the amyloid beta deposits and NeuN in the hippocampus were evaluated with immunohistochemistry. Brain neurotrophic derived factor (BDNF) and tyrosine kinase B (TrkB) expressions were examined by western blot analysis.

Results: LFE treatment significantly ameliorated learning and memory deficits in AD mice, as shown by increased time spent in the target zone during probe tests. In addition, LFE significantly decreased Aβ deposits, increased NeuN-positive cells, and upregulated the expression of BDNF and TrkB in the 3xTg AD mice.

Conclusions: The present study suggests that LFE treatment can be a useful strategy for treating memory impairment induced by several neurodegenerative diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jep.2015.06.026DOI Listing
August 2015

Attenuation of cellular toxicity by calpain inhibitor induced by bacterial endotoxin: a mechanistic study using muscle precursor cells as a model system.

Mol Biol Rep 2015 Aug 27;42(8):1281-8. Epub 2015 Mar 27.

Department of Animal Science and Biotechnology, Chonbuk National University, Chonju, 561-756, Republic of Korea.

This investigation was under taken to explore probable mechanisms and signal pathways involved in cytotoxicity induced by bacterial endotoxin lipopolysaccharide (LPS). Herein, we selected muscle precursor C2C12 myoblasts as representative cells to test effect of calpain inhibitor 3-(4-iodophenyl)-2-mercapto-(Z)-2-propenoic acid (PD150606) on LPS induced inflammation and apoptosis. In order to rule out the toxicity of endotoxin, mouse myoblasts were exposed to various concentrations of LPS and viability of cells and morphology were assessed using CCK-8 assay and simple microscopy respectively. Apoptotic cell death was examined by fluorescence microscope at regular time intervals. Additionally, LPS induced apoptosis in C2C12 cells were determined by mRNA expression of µ-calpain, caspase-3 and tumor necrosis factor alpha (TNF-α) and were quantified by qRT-PCR. Our results point out that LPS stimulation produced dose dependent toxicity in muscle precursor cells. Pre-treatment with a calpain inhibitor can significantly attenuate LPS-induced inflammation/apoptosis. Results of present research determined that mRNA expression of aforesaid genes was amplified (p<0.05) in LPS stimulated C2C12 cells, whereas a noticeable drop off in mRNA expression of these genes was observed when pre-exposed with calpain inhibitor PD150606. Our study has outlined the current understanding regarding the connection between µ-calpain and caspase-3 in skeletal muscle wasting and as a result provides suitable choice for designing promising chemotherapeutic system for muscle illness and atrophy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11033-015-3869-7DOI Listing
August 2015

Antiapoptotic effect of a novel synthetic peptide from bovine muscle and MPG peptide on H2O2-induced C2C12 cells.

In Vitro Cell Dev Biol Anim 2014 Aug 14;50(7):630-9. Epub 2014 May 14.

Department of Animal Science and BK21 PLUS program, Chonbuk National University, Jeonju, 561-756, South Korea.

The objective of this study was to evaluate antioxidant and antiapoptotic effects of a novel peptide (T.peptide) isolated from bovine and commercially available MPG peptide. The amino acid sequences of the T.peptide were (Glu-Val-Pro-Glu-Val-His-Glu-Glu-Val). The antioxidant activities of these peptides were determined by measuring the 1,1-diphenyl-2-picrylhydrazyl (DPPH•) and 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS+•) radical scavenging assays. The in vitro cytotoxicity of T.peptide and MPG peptide was determined against H2O2-induced C2C12 cells. H2O2-induced apoptosis in C2C12 cells were determined by mRNA expression of caspase-3. Moreover, the mRNA expression of tumor necrosis factor alpha (TNF-α) and nuclear factor kappa B (NF-κB) were assayed by reverse transcription polymerase chain reaction. The findings of the study indicate that the mRNA expression of TNF-α and NF-κB are significantly (p < 0.05) increased in H2O2-induced C2C12 cells, whereas a significant decrease (p < 0.05) in these mRNA expressions are observed when pretreated with T.peptide or MPG peptide. Pretreatment with MPG or T.peptides is also found to significantly (p < 0.05) decrease the mRNA expression of caspase-3 in H2O2-induced C2C12 cells. The results of the study demonstrate that both T.peptide and MPG peptide could reduce the DPPH• and ABTS+• radical and inhibit cytotoxicity against H2O2-induced injury, resulting in prevention of free radical generation and subsequent apoptotic cell death, which indicates the potential of bovine meat as a source of antioxidant peptides.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11626-014-9745-2DOI Listing
August 2014
-->