Paleostress of the Joseon and Pyeongan Supergroups in South Korea using the New Calcite Strain Gauge (NCSG)

( Bo An Jang ),( Chin Surk Ko ),( Jung Han Kim ),( Cheong Bin Kim ),( Seong Seung Kang2 ) 대한지질공학회 2014 지질공학 Vol.24 No.3

Limestone bodies under the tectonic environment have experienced various tectonic processes, and also changed the stress state. In this study, calcite twins found in limestones of the Joseon Supergroup and Pyeongan Supergroup in the northeastern part of the Ogcheon Belt, South Korea were measured, then the paleostress (i.e., the maximum shortening axis) was reconstructed using the new calcite strain gauge (NCSG) technique. The average twin thickness and average twin intensity increase as the total twin strain increases. We utilize the appearance of twins, the average twin thickness and average twin intensity, and the total twin strain to estimate that the observed calcite twins were produced at temperatures of < 200oC in the Joseon Supergroup and 170oC in the Pyeongan Supergroup. In the Joseon Supergroup, the dominant direction of the maximum shortening axis WNW-ESE to NW-SE; NE-SW shortening is also observed. The maximum shortening axes in the Pyeongan Supergroup are oriented NW-SE and NE-SW. The NE-SW direction of maximum shortening is associated with the occurrence of the Songrim orogeny of the Paleozoic to Early Jurassic, and the NW-SE direction of maximum shortening correlates to the Daebo orogeny of the Early Jurassic to Late Jurassic. It is thus concluded that the paleostress across the study area changed from NE-SW to NW-SE during the Mesozoic.

Changes in hippocalcin expression in cortical neurons and glial cells by epigallocatechin gallate administration in an animal model of stroke

Ju-Bin Kang(Ju-Bin Kang),Dong-Ju Park(Dong-Ju Park),Jae-You Kim(Jae-You Kim),Hyeun-Gyoung(Hyeun-Gyoung ),Phil-Ok Koh(Phil-Ok Koh) 한국예방수의학회 2023 예방수의학회지 Vol.47 No.2

Ischemic stroke causes brain damage and neuronal cell death by depriving oxygen and nutrients and releasing excessive levels of glutamate and intracellular calcium. Epigallocatechin gallate (EGCG) is a polyphenolic compound present in green tea. It has antioxidant, anti-inflammatory, and neuroprotective effects. Hippocalcin is a calcium binding protein that regulates calcium concentration, neuronal differentiation, neuronal excitability, and neuronal cell death. In this study, we investigated whether EGCG regulates the expression of hippocalcin in neurons and astrocytes after focal cerebral ischemia. Cerebral ischemia was induced by meddle cerebral artery occlusion (MCAO). EGCG (50 mg/kg) or PBS was injected into the abdominal cavity just before MCAO surgery. Neurobehavioral tests were performed to evaluate the effect of EGCG on neurological behavioral deficits 24 h after MCAO surgery. Immunofluorescence staining was performed to evaluate the positive response to hippocalcin in the cerebral cortex after MCAO surgery. We also detected the positive reactions of neuronal nuclear protein (NeuN) and glial fibrillary acidic protein (GFAP) as markers of neuron and astrocyte, respectively. MCAO caused severe neurological impairment and EGCG treatment attenuated these impairments. MCAO damage reduced the number of NeuN-positive cells and increased the number of GFAP-positive cells. This result indicates a decrease in neurons and an increase in astrocytes. However, EGCG alleviated these changes caused by MCAO damage. MCAO reduced the number of hippocalcin-positive cells in neurons and astrocytes, and EGCG treatment attenuated these reductions. Hippocalcin exerts neuroprotective effect through regulating intracellular calcium concentration. In conclusion, EGCG regulates the expression of hippocalcin in neurons and astrocytes and has neuroprotective effects in focal cerebral ischemia.

Prediction of tyrosinase inhibitory activities from HPLC chromatograms of Morus alba root bark extracts

KANG Kyo Bin,KIM Tae Bum,MOON Eunhye,KIM Seung Hyun,KIM Jinwoong,SUNG Sang Hyun 大韓藥學會 2012 大韓藥學會 總會 및 學術大會 Vol.2012 No.1

UHPLC-ESI-qTOF-MS Analysis of Cyclopeptide Alkaloids in the Seeds of Ziziphus jujuba var. spinosa

Kang, Kyo Bin,Jang, Dae Sik,Kim, Jinwoong,Sung, Sang Hyun Korean Society for Mass Spectrometry 2016 Mass spectrometry letters Vol.7 No.2

An UHPLC-ESI-qTOF-MS analytical method was developed for cyclopeptide alkaloids in the seeds of Ziziphus jujuba var. spinosa (Semen Ziziphi Spinosae), which is a commonly used herb in Chinese and Korean traditional medicines. Considering the basicity of cyclopeptide alkaloids, a specific separation method was developed for an UHPLC system. The compounds were detected by DAD and ESI-qTOF-MS, and their fragmentation patterns were also acquired by MS^E technologies. Peak-picking of major compounds was performed with nine previously isolated compounds and two reference standard compounds. Tandem MS fragmentation behaviors of type-Ia and -Ib cyclopeptide alkaloids were investigated with the acquired data to develop a strategy for dereplication of other cyclopeptide alkaloid compounds in Z. jujuba var. spinosa. Two more cyclopeptide alkaloids were tentatively identified with UHPLC-ESI-qTOF-MS using this method.

국내 코로나19 판데믹 기간 발생한 입원을 요하는 소아청소년 지역사회폐렴의 원인과 위험 인자

Kang Hae Min,Song Seung Ha,Ahn Bin,Park Ji Young,Kang Hyunmi,Kwak Byung Ok,Kim Dong Hyun,Lee Joon Kee,Choi Soo-Han,Choi Jae Hong,Choi Eun Hwa,Yun Ki Wook 대한소아감염학회 2023 Pediatric Infection and Vaccine Vol.30 No.1

Purpose: This study aimed to identify the etiology and risk factors of community-acquired pneumonia (CAP) requiring hospitalization in Korean children during the coronavirus disease 2019 (COVID-19) pandemic. Methods: Clinical information of children admitted with CAP to Seoul National University Children’s Hospital (SNUCH) between January 1, 2021, and February 28, 2022, was retrospectively collected and analyzed. In addition, the etiologic diagnosis and demographic data of children with CAP who were discharged at the other seven hospitals between January and February 2022 were collected. Pneumonia was diagnosed using strict criteria comprising clinical symptoms, physical examination findings, and chest radiographic findings. Results: Among 91 children hospitalized with CAP at SNUCH during the 14-month period, 68.4% were aged <5 years and 79.1% had underlying diseases. Among the 95 CAP cases, respiratory assistance was required in 70.5%, and the use of a ventilator was required in 20.0%. A total of five patients expired, all of whom were either immunocompromised or had underlying neurological diseases. Neurological diseases and immunosuppression were significantly correlated with respiratory assistance (P=0.003) and death (P=0.014). A total of 55% of the detected respiratory pathogens were viruses, the most common of which was rhinovirus at 35.9%. Among the 169 children hospitalized for CAP at the eight institutions, ≥1 respiratory virus was detected in 92.3%, among which respiratory syncytial virus (79.8%) was the most prevalent. Conclusions: Even during the COVID-19 pandemic, Korean children were hospitalized with CAP caused by seasonal respiratory viral pathogens. Although atypical and pyogenic bacteria were not detected, continuous clinical monitoring and further prospective studies should be conducted.

Towards Sympathetic Cooling of Highly Charged Ions by Laser-Cooled Ca+ Ions

Kang-Bin Im,Gi Dong Kim,박영호,신택수 한국물리학회 2020 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.76 No.7

The long-term goal of the Penning trap system for the heavy ion accelerator named RAON in Korea is to obtain an order of magnitude higher mass accuracy for short-lived rare isotopes. For that purpose, we are developing a sympathetic cooler for highly charged ions by exploiting laser-cooled Ca+ ions. We installed a prototype octagon chamber with a calcium atom source, a Paul trap, and a helical resonator for the high-voltage RF supply. The laser system is composed of three extended cavity diode lasers (423, 397, 866 nm) plus one UV diode laser (375 nm). The optical frequency stabilization setup is made up of a wavelength meter, a multichannel fiber switch and a PXI system with an 8-channel analog output module. After having obtained a resonant ionization signal from the calcium atomic beam, we applied the RF voltage to the trap electrodes and illuminated the cooling lasers at the center of the trap. We successfully observed a laser-cooled ion bunch and a linearly aligned ion string by using imaging optics and an electron multiplying charge coupled device (EMCCD) camera. In addition to the experimental effort, we performed a simulation study for cooling 132Sn10+ ions inside a laser-cooled 40Ca+ Coulomb crystal by using a parallel computation technique.

Catechin-Bound Ceanothane-Type Triterpenoid Derivatives from the Roots of <i>Zizyphus jujuba</i>

Kang, Kyo Bin,Kim, Hyun Woo,Kim, Jung Wha,Oh, Won Keun,Kim, Jinwoong,Sung, Sang Hyun American Society of Pharmacognosy 2017 Journal of natural products Vol.80 No.4

<P>Three unprecedented ceanothane-type triterpenoids, ent-epicatechinoceanothic acid A (1), ent-epicatechinoceanothic acid B (2), and epicatechino-3-deoxyceanothetric acid A (3), containing C-C bond linkages with catechin moieties, were isolated from the roots of Zizyphus jujuba. Their chemical structures, including absolute configurations, were established by spectroscopic analysis and calculation of their ECD spectra. A possible biogenetic pathway for C-C bond formation between the catechin and the triterpenoid moieties is presented. Compound 1 was evaluated for its antiproliferalive activity on HSC-T6 hepatic stellate cells.</P>

Chemical and genomic diversity of six <i>Lonicera</i> species occurring in Korea

Kang, Kyo Bin,Kang, Shin-Jae,Kim, Mi Song,Lee, Dong Young,Han, Sang Il,Kim, Tae Bum,Park, Jee Young,Kim, Jinwoong,Yang, Tae-Jin,Sung, Sang Hyun Elsevier 2018 Phytochemistry Vol.155 No.-

<P><B>Abstract</B></P> <P> <I>Lonicera</I> spp. (Caprifoliaceae) are important not only as a common medicinal herb in East Asia but also as one of the most problematic invasive species in North America. In the present study, we performed a systemic analysis of genomic and chemical diversity among six <I>Lonicera</I> species occurring in Korea, <I>L. japonica</I>, <I>L. maackii</I>, <I>L. insularis</I>, <I>L. sachalinensis</I>, <I>L. praeflorens</I>, and <I>L. vesicaria</I>, using chloroplast DNA whole genome shotgun (WGS) sequencing and LC–MS analyses. The phylogenetic and phylochemical relationships did not coincide with each other, but partial consistency could be found among them. InDel-based cDNA marker for authentication was developed based on the genome sequences. Flavonoids, iridoids, and organic acids were identified in the LC–MS analyses, and their inter-species distribution and localization were also revealed.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Phylogeny between six <I>Lonicera</I> species was supposed based on chloroplast genome sequences. </LI> <LI> Specialized metabolites were profiled and compared by LC–MS. </LI> <LI> Partial consistency was found between genomic and chemical phylogeny. </LI> <LI> An Indel-based DNA barcode was developed for authentication of plants. </LI> <LI> Difference in chemotypes was suggested to be caused by ecological roles of iridoids. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Development and Validation of the Mental Health Scale for Maltreated Children

Bin-Na Kim,Hyeseon Jo,Suhyeon Kang,Soo-Yeon Kim,Ha-young Park,Jungkyu Park,Hyo Shin Kang 대한신경정신의학회 2024 PSYCHIATRY INVESTIGATION Vol.21 No.3

Objective This study aimed to develop and validate a comprehensive self-report questionnaire to assess emotional and behavioral problems and psychological trauma in maltreated children.Methods The Mental Health Scale for Maltreated Children (MHS-MC) was constructed to encompass five major symptoms (depression, anxiety, inattention/hyperactivity/impulsivity, aggression/defiance, and psychological trauma) prevalent in maltreated children. Critical items and ego-resilience subscale were also devised to increase clinical utility. After informed consent, 205 children (maltreated children, n=157, 76.6%) were recruited nationwide, and they answered a package of self-report measures, including the MHS-MC. Reliability, construct validity, concurrent validity, and criterion-related validity were examined to explore the psychometric properties.Results The reliability was good to excellent. Confirmatory factor analysis yielded a five-factorial solution for the symptom subscales supporting construct validity. In logistic regression, the total scores of the MHS-MC predicted membership in the maltreated group. Criterion-related validity was generally satisfactory in that all subscales of the MHS-MC showed significant correlations with relevant measures in the expected direction.Conclusion This is the first attempt to develop a comprehensive psychological scale based on nationwide data collected from maltreated Korean children. We hope that the continued standardization of this scale will contribute to evidence-based clinical and policy decisionmaking for maltreated children.

High-performance bipolar host materials for blue TADF devices with excellent external quantum efficiencies

Kang, J.,Hong, T.,Kim, H.,Son, Y.,Lampande, R.,Kang, B.,Lee, C.,Bin, J. K.,Lee, B.,Yang, J. Royal Society of Chemistry 2016 Journal of materials chemistry. C, Materials for o Vol.4 No.20

<P>New bipolar host molecules composed of carbazole, pyridoindole, and dibenzothiophene (DBT) were synthesized for blue thermally activated delayed fluorescence (TADF)-based organic light-emitting diodes (OLEDs). 2,8-Di(9H-carbazol-9-yl) dibenzo[b,d]thiophene, 9-(8-(9H-carbazol-9-yl)dibenzo[b,d]thiophen-2yl)-9H-pyrido[2,3-b]indole, and 2,8-bis(9H-pyrido[2,3-b]indol-9-yl)dibenzo[b,d]thiophene were prepared based on the selective reactivity at the 2,8-positions of DBT. The new symmetric and asymmetric host materials exhibited high triplet energies (2.89-2.95 eV). 4,5-Di(9H-carbazol-9-yl)phthalonitrile (2CzPN) was selected as an emitting dopant for achieving sky-blue emissions in TADF-OLEDs. 2CzPN-doped TADF-OLEDs, whose configuration is ITO (50 nm)/HATCN (7 nm)/TAPC (75 nm)/host:6% 2CzPN (20 nm)/TmPyPB (50 nm)/LiF (15 nm)/Al (100 nm), showed low driving voltages and high external quantum efficiencies (EQEs). These results are attributed to the well-controlled bipolar character of the host giving a better charge balance in the emitting layer. In particular, the device containing ZDN: 6% 2CzPN showed an unprecedentedly high EQE of 25.7% (at 0.074 mA cm(-2)).</P>