Light Scattering Study of Glass Transition Temperatures of Glucose-Water Mixtures

서정아,오지영,김형국,황윤회 부산대학교 유전체물성연구소 2004 유전체 논문집 Vol.3 No.

We studied glass transition temperatures of glucose-water mixtures by using Brillouin light scattering. We fitted the polarized components of the Brillouin spectra measured by backscattering geometry to simple Lorentzian form and estimated the glass transition temperature from the slope of the temperature-dependent Brillouin peak shift.

[PD-0011] Functional study of CTP synthases during early seed development in rice

Jiyoung Kim(Jiyoung Kim),Sunghuyun Kwon(Sunghuyun Kwon),Gynheung An(Gynheung An),Jinmi Yoon(Jinmi Yoon),Lae-Hyeon Cho(Lae-Hyeon Cho) 한국육종학회 2022 한국육종학회 공동학술발표집 Vol.2022 No.-

Internet Gaming Disorder and Mental Health Literacy: A Latent Profile Analysis of Korean Adolescents

Jiyoung Yoon,JongSerl Chun,Soo-Young Bhang 대한신경정신의학회 2024 PSYCHIATRY INVESTIGATION Vol.21 No.3

Objective This study identified latent subtypes of mental health literacy (MHL) for Internet gaming disorder (IGD) and explored their characteristics and differences in various factors in adolescents.Methods This study analyzed secondary data from the 2019 Youth Smart Digital Media Survey and included data from 1,936 middle and high school students (14–18 years old). Thirteen items of the MHL questionnaire were used for latent profile analysis. We compared the characteristics and predictors of the identified types using various statistical analyses, including one-way ANOVA, chi-square test, and multinomial logistic regression.Results We identified three subtypes of MHL for IGD in adolescents: “low perception-prefer informal resources,” “moderate perception-preferred resources unclear,” and “high perception-prefer professional resources.” Subtypes showed significant differences in sex, age, family affluence, e-learning time during weekdays, mental health risks, level of problematic smartphone use, and IGD. All variables except IGD predicted one or more latent types.Conclusion Practical interventions are required to improve IGD MHL, including customized prevention based on the differences between the three types.

Anatomical analysis of the resected roots of mandibular first molars after failed non-surgical retreatment

Jiyoung Yoon,Jihyun Bae,Yong-Hoon Choi,Byeong-Hoon Cho 대한치과보존학회 2018 Restorative Dentistry & Endodontics Vol.43 No.2

Objectives Understanding the reason for an unsuccessful non-surgical endodontic treatment outcome, as well as the complex anatomy of the root canal system, is very important. This study examined the cross-sectional root canal structure of mandibular first molars confirmed to have failed non-surgical root canal treatment using digital images obtained during intentional replantation surgery, as well as the causative factors of the failed conventional endodontic treatments. Materials and Methods This study evaluated 115 mandibular first molars. Digital photographic images of the resected surface were taken at the apical 3 mm level and examined. The discolored dentin area around the root canal was investigated by measuring the total surface area, the treated areas as determined by the endodontic filling material, and the discolored dentin area. Results Forty 2-rooted teeth showed discolored root dentin in both the mesial and distal roots. Compared to the original filled area, significant expansion of root dentin discoloration was observed. Moreover, the mesial roots were significantly more discolored than the distal roots. Of the 115 molars, 92 had 2 roots. Among the mesial roots of the 2-rooted teeth, 95.7% of the roots had 2 canals and 79.4% had partial/complete isthmuses and/or accessory canals. Conclusions Dentin discoloration that was not visible on periapical radiographs and cone-beam computed tomography was frequently found in mandibular first molars that failed endodontic treatment. The complex anatomy of the mesial roots of the mandibular first molars is another reason for the failure of conventional endodontic treatment.

GRIM19 promote bown adipogenesis and prevents obesity via regualtion of adipose tissue and immune cell

Jiyoung Kim,JooYeon Jhun,Jin Seok Woo,Seung Hoon Lee,Jeong-Hee Jeong,KyungAh Jung,Wonhee Hur,Seon-Yeong Lee,Jae Yoon Ryu,Young-Mee Moon,Yoon Ju Jung,Kyo Young Song,Kiyuk Chang,Seung Kew Yoon,Sung-Hwan 한국실험동물학회 2021 한국실험동물학회 학술발표대회 논문집 Vol.2021 No.7

Obesity, a condition characterized by excessive accumulation of body fat, is a metabolic disorder related to an increased risk of chronic inflammation. Obesity is mediated by signal transducer and activator of transcription (STAT) 3, which is regulated by genes associated with retinoid interferon-induced mortality (GRIM) 19, a protein ubiquitously expressed in various human tissues. In this study, we investigated the role of GRIM19 in diet-induced obese C57BL/6 mice via intra venous or intramuscular administration of a plasmid encoding GRIM19. Splenocytes from wild-type and GRIM19-overexpressing mice were compared using enzyme-linked immunoassay, real-time polymerase chain reaction, Western blotting, flow cytometry, and histological analyses. GRIM19 attenuated the progression of obesity by regulating STAT3 activity and enhancing brown adipose tissue (BAT) differentiation. GRIM19 regulated the differentiation of mouse-derived 3T3-L1 preadipocytes into adipocytes, while modulating gene expression in white adipose tissue (WAT) and BAT. GRIM19 overexpression reduced diet-induced obesity and enhanced glucose and lipid metabolism in the liver. Moreover, GRIM19 overexpression reduced WAT differentiation and induced BAT differentiation in obese mice. GRIM19-transgenic mice exhibited reduced mitochondrial superoxide levels and a reciprocal balance between Th17 and Treg cells. These results suggest that GRIM19 attenuates the progression of obesity by controlling adipocyte differentiation.

A Study of the Effects of Korean Ox Legs Soup on Bone Balance by Osteoblast Differentiation and Osteoclastogenesis

Jiyoung Yoon,Nami Joo,Heesun Jeong,Dasol Kim,Soonyoung Choi 한국식품영양학회 2014 한국식품영양학회 학술대회논문집(학술심포지움) Vol.2014 No.12

Atypical Manifestation of Primary Hepatocellular Carcinoma and Hepatic Malignancy Mimicking Lesions

Jiyoung Yoon,So Hyun Park,Su Joa Ahn,Young Sup Shim 대한영상의학회 2022 대한영상의학회지 Vol.83 No.4

Hepatocellular carcinoma (HCC) can be diagnosed noninvasively on multiphasic CT and MRI based on its distinctive imaging findings. These features include arterial phase hyperenhancement and washout on portal or delayed phase images. However, radiologists face significant diagnostic challenges because some HCCs exhibit atypical imaging characteristics. In addition to many HCC-mimicking lesions, such as arterioportal shunts, combined HCC-cholangiocarcinoma, intrahepatic cholangiocarcinoma, and hemangioma present a challenge for radiologists in actual clinical practice. The ability to distinguish HCCs from mimickers on initial imaging examinations is crucial for appropriate management and treatment decisions. Therefore, this pictorial review presents the imaging findings of atypical HCCs and HCCs mimicking malignant and benign lesions and discusses important clues that may help narrow down the differential diagnosis.

Reviews and syntheses: Ocean iron fertilization experiments - past, present, and future looking to a future Korean Iron Fertilization Experiment in the Southern Ocean (KIFES) project

Yoon, Joo-Eun,Yoo, Kyu-Cheul,Macdonald, Alison M.,Yoon, Ho-Il,Park, Ki-Tae,Yang, Eun Jin,Kim, Hyun-Cheol,Lee, Jae Il,Lee, Min Kyung,Jung, Jinyoung,Park, Jisoo,Lee, Jiyoung,Kim, Soyeon,Kim, Seong-Su,Ki Copernicus GmbH 2018 Biogeosciences Vol.15 No.19

<P><p><strong>Abstract.</strong> Since the start of the industrial revolution, human activities have caused a rapid increase in atmospheric carbon dioxide (<span class='inline-formula'>CO₂</span>) concentrations, which have, in turn, had an impact on climate leading to global warming and ocean acidification. Various approaches have been proposed to reduce atmospheric <span class='inline-formula'>CO₂</span>. The Martin (or iron) hypothesis suggests that ocean iron fertilization (OIF) could be an effective method for stimulating oceanic carbon sequestration through the biological pump in iron-limited, high-nutrient, low-chlorophyll (HNLC) regions. To test the Martin hypothesis, 13 artificial OIF (aOIF) experiments have been performed since 1990 in HNLC regions. These aOIF field experiments have demonstrated that primary production (PP) can be significantly enhanced by the artificial addition of iron. However, except in the Southern Ocean (SO) European Iron Fertilization Experiment (EIFEX), no significant change in the effectiveness of aOIF (i.e., the amount of iron-induced carbon export flux below the winter mixed layer depth, MLD) has been detected. These results, including possible side effects, have been debated amongst those who support and oppose aOIF experimentation, and many questions concerning the effectiveness of scientific aOIF, environmental side effects, and international aOIF law frameworks remain. In the context of increasing global and political concerns associated with climate change, it is valuable to examine the validity and usefulness of the aOIF experiments. Furthermore, it is logical to carry out such experiments because they allow one to study how plankton-based ecosystems work by providing insight into mechanisms operating in real time and under in situ conditions. To maximize the effectiveness of aOIF experiments under international aOIF regulations in the future, we therefore suggest a design that incorporates several components. (1) Experiments conducted in the center of an eddy structure when grazing pressure is low and silicate levels are high (e.g., in the SO south of the polar front during early summer). (2) Shipboard observations extending over a minimum of <span class='inline-formula'>∼40</span> days, with multiple iron injections (at least two or three iron infusions of <span class='inline-formula'>∼2000</span><span class='thinspace'></span><span class='inline-formula'>kg</span> with an interval of <span class='inline-formula'>∼10</span>-15 days to fertilize a patch of 300<span class='thinspace'></span><span class='inline-formula'>km²</span> and obtain a <span class='inline-formula'>∼2</span><span class='thinspace'></span><span class='inline-formula'>nM</span> concentration). (3) Tracing of the iron-fertilized patch using both physical (e.g., a drifting buoy) and biogeochemical (e.g., sulfur hexafluoride, photosynthetic quantum efficiency, and partial pressure of <span class='inline-formula'>CO₂</span>) tracers. (4) Employment of neutrally buoyant sediment traps (NBST) and application of the water-column-derived thorium-234 (<span class='inline-formula'>²³⁴Th</span>) method at two depths (i.e., just below the in situ MLD and at the winter MLD), with autonomous profilers equipped with an underwater video profiler (UVP) and a transmissometer. (5) Monitoring of side effects on marine/ocean ecosystems, including production of climate-relevant gases (e.g., nitrous oxide, <span class='inline-formula'>N₂O</span>; dimethyl sulfide, DMS; and halogenated volatile organic compounds, HVOCs), decline in oxygen inventory, and development of toxic algae blooms, with optical-sensor-equipped autonomous moored profilers and/or autonomous benthic vehicles. Lastly, we introduce the scientific aOIF<span id='page5848'/> experimental design guidelines for a future Korean Iron Fertilization Experiment in the Southern Ocean (KIFES).</p> </P>

Multifunctional ultrasmall superparamagnetic iron oxide nanoparticles as a theranostic agent

Yoon, Jiyoung,Cho, Sun Hang,Seong, Hasoo Elsevier 2017 Colloids and surfaces. A, Physicochemical and engi Vol.520 No.-

<P><B>Abstract</B></P> <P>A new theranostic ultrasmall superparamagnetic iron oxide nanoparticle (USPIONP)—consisting of an iron oxide nanoparticle (IONP) core, amphiphilic poly(aspartic acid) graft copolymer (P), and a model anticancer drug, epirubicin (EPI)—was developed and characterized. The graft copolymer P, poly(2-hydroxyethylaspartamide)-mPEG-C<SUB>16</SUB>, was synthesized by a polysuccinimide ring-opening reaction. The P-IONP, the IONP core of which was coated with polymer P, was synthesized using a co-precipitation method. The P-IONP was a USPIONP with an IONP core of diameter 6–9nm and a hydrodynamic diameter of 41nm. The EPI-loaded P-IONP (EPI-P-IONP) had a hydrodynamic diameter of 53nm. The remarkably high relaxivity, <I>r<SUB>2</SUB> </I>, of 605.5s<SUP>−1</SUP> mM<SUP>−1</SUP> of EPI-P-IONP corresponded to magnetic resonance contrast enhancement 2.7-fold that of a commercial contrast agent. The EPI encapsulation efficiency was 81%, and EPI was released from EPI-P-IONP in a sustained manner. P-IONP had negligible cytotoxicity against HeLa cells, while cytotoxicity increased in an EPI-dose-dependent manner after 4h incubation with EPI-P-IONP. Cellular uptake of EPI from EPI-P-IONP was comparable to that of free EPI, as determined by flow cytometry. Confocal microscopy confirmed nuclear uptake of EPI released from EPI-P-IONP. These results suggest that the P-IONP has potential as an imaging agent and a therapeutic agent, and thus as a theranostic agent.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A theranostic agent, a model anticancer drug, epirubicin (EPI)-loaded ultrasmall superparamagnetic iron oxide nanoparticle (EPI-USPIONP), which has an iron oxide nanoparticle (IONP) core and poly(aspartic acid) graft copolymer (P), was successfully prepared. </LI> <LI> The P-IONP, the IONP of which was coated with polymer P, was a USPIONP with an IONP core diameter of 6–9nm and a hydrodynamic diameter of 41nm. </LI> <LI> EPI-loaded P-IONP (EPI-P-IONP) had a high encapsulation efficiency of EPI and exhibited a sustained release of the EPI. </LI> <LI> EPI-P-IONP showed a high relaxivity, <I>r<SUB>2</SUB> </I>, value, corresponding to contrast enhancement effect ∼2.7-fold greater than that of commercial contrast agent. </LI> <LI> EPI released from EPI-P-IONPs was cytotoxic against cancer cells and cellular uptake studies confirmed nuclear uptake of the EPI released from EPI-P-IONPs, indicating potential of the P-IONP as a theranostic agent. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Preoperative Magnetic Resonance Imaging Features Associated with Positive Resection Margins in Patients with Invasive Lobular Carcinoma

Yoon Jiyoung,Kim Eun-Kyung,Kim Min Jung,Moon Hee Jung,Yoon Jung Hyun,박영진 대한영상의학회 2020 Korean Journal of Radiology Vol.21 No.8

Objective: To investigate preoperative magnetic resonance imaging (MRI) findings associated with resection margin status in patients with invasive lobular carcinoma (ILC) who underwent breast-conserving surgery. Materials and Methods: One hundred and one patients with ILC who underwent preoperative MRI were included. MRI (tumor size, multifocality, type of enhancing lesion, distribution of non-mass enhancement [NME], and degree of background parenchymal enhancement) and clinicopathological features (age, pathologic tumor size, presence of ductal carcinoma in situ [DCIS] or lobular carcinoma in situ, presence of lymph node metastases, and estrogen receptor/progesterone receptor/human epidermal growth factor receptor type 2 status) were analyzed. A positive resection margin was defined as the presence of invasive cancer or DCIS at the inked surface. Logistic regression analysis was performed to determine pre- and postoperative variables associated with positive resection margins. Results: Among the 101 patients, 21 (20.8%) showed positive resection margins. In the univariable analysis, NME, multifocality, axillary lymph node metastasis, and pathologic tumor size were associated with positive resection margins. With respect to preoperative MRI findings, multifocality (odds ratio [OR] = 3.977, p = 0.009) and NME (OR = 2.741, p = 0.063) were associated with positive resection margins in the multivariable analysis, although NME showed borderline significance. Conclusion: In patients with ILC, multifocality and the presence of NME on preoperative breast MRI were associated with positive resection margins.