The efficacy of a 2,4-diaminoquinazoline compound as an intranasal vaccine adjuvant to protect against influenza A virus infection in vivo

Noh Kyungseob,Jeong Eun Ju,An Timothy,Shin Jin Soo,Kim Hyejin,Han Soo Bong,Kim Meehyein 한국미생물학회 2022 The journal of microbiology Vol.60 No.5

Adjuvants are substances added to vaccines to enhance antigen- specific immune responses or to protect antigens from rapid elimination. As pattern recognition receptors, Toll-like receptors 7 (TLR7) and 8 (TLR8) activate the innate immune system by sensing endosomal single-stranded RNA of RNA viruses. Here, we investigated if a 2,4-diaminoquinazolinebased TLR7/8 agonist, (S)-3-((2-amino-8-fluoroquinazolin- 4-yl)amino)hexan-1-ol (named compound 31), could be used as an adjuvant to enhance the serological and mucosal immunity of an inactivated influenza A virus vaccine. The compound induced the production of proinflammatory cytokines in macrophages. In a dose-response analysis, intranasal administration of 1 μg compound 31 together with an inactivated vaccine (0.5 μg) to mice not only enhanced virus-specific IgG and IgA production but also neutralized influenza A virus with statistical significance. Notably, in a virus-challenge model, the combination of the vaccine and compound 31 alleviated viral infection-mediated loss of body weight and increased survival rates by 40% compared with vaccine only-treated mice. We suggest that compound 31 is a promising lead compound for developing mucosal vaccine adjuvants to protect against respiratory RNA viruses such as influenza viruses and potentially coronaviruses.

Data compression of excitatory postsynaptic potentials

Hyejin An,Kab-mun Cha,Se-young Choi,Hyun-Chool Shin IET 2015 Electronics letters Vol.51 No.18

<P>Reducing the size of biosignal data is important because a huge amount of data is made by various experiments. In this reported work excitatory postsynaptic potentials (EPSPs) which are one of the biosignal types are efficiently compressed. To the best of authors' knowledge, EPSPs compression has not been studied yet. The EPSP signal has a feature that the adjacent signals in a single excitatory postsynaptic potential have similar characteristics. Using this feature, a method is proposed which removes the temporal redundancy and statistical redundancy of EPSPs. The compressed and reconstructed EPSPs are similar to the original signal without the loss of analytic information.</P>

Analysis of transcriptome change by HMTs in liver disease models

Hyejin An,Seunghee Lee 한국분석과학회 2021 학술대회논문집 Vol.2021 No.5

Molecular Characterization of 170 New gDNA-SSR Markers for Genetic Diversity in Button Mushroom (Agaricus bisporus)

( Hyejin An ),( Ick-hyun Jo ),( Youn-lee Oh ),( Kab-yeul Jang ),( Won-sik Kong ),( Jwa-kyung Sung ),( Yoon-sup So ),( Jong-wook Chung ) 한국균학회 2019 Mycobiology Vol.47 No.4

We designed 170 new simple sequence repeat (SSR) markers based on the whole-genome sequence data of button mushroom (Agaricus bisporus), and selected 121 polymorphic markers. A total of 121 polymorphic markers, the average major allele frequency (M_AF) and the average number of alleles (N_A) were 0.50 and 5.47, respectively. The average number of genotypes (N_G), observed heterozygosity (H_O), expected heterozygosity (H_E), and polymorphic information content (PIC) were 6.177, 0.227, 0.619, and 0.569, respectively. Pearson’s correlation coefficient showed that MAF was negatively correlated with N_G (_0.683), N_A (_0.600), H_O (_0.584), and PIC (_0.941). N_G, N_A, H_O, and PIC were positively correlated with other polymorphic parameters except for MAF. UPGMA clustering showed that 26 A. bisporus accessions were classified into 3 groups, and each accession was differentiated. The 121 SSR markers should facilitate the use of molecular markers in button mushroom breeding and genetic studies.

Genetic diversity and population structure of Chinese ginseng accessions using SSR markers

An, Hyejin,Park, Jong-Hyun,Hong, Chi Eun,Raveendar, Sebastin,Lee, Yi,Jo, Ick-Hyun,Chung, Jong-Wook The Korean Society of Plant Biotechnology 2017 식물생명공학회지 Vol.44 No.3

The need to preserve and use plant genetic resources is widely recognized, and the prospect of dwindling plant genetic diversity, coupled with increased demands on these resources, has made them a topic of global discussion. In the present study, the genetic diversity and population structure of 73 ginseng accessions collected from six regions in China were analyzed using eight simple sequence repeat (SSR) markers. Major allele frequencies ranged between 0.38 ~ 0.78, with a mean allele frequency value of 0.571. The number of alleles discovered ranged from 3 to 10 per accession, with a mean number of 7; 56 alleles were discovered in total. Gene diversity (GD) and polymorphic information content (PIC) values were similar to each other, and they ranged from 0.36 ~ 0.77 (mean 0.588) and 0.33 ~ 0.74 (mean 0.548), respectively. Accessions were divided into three clusters based on their phylogenetic relationships and genetic similarities, and although the populations were similar, they were not classified according to the region. Regional genetic diversity was also similar, with slight differences observed based on the number of accessions per region. It is expected that the findings of the present study can provide basic data for future studies on ginseng genetic diversity and for breeding ginseng cultivars.

Spore-forming probiotic bacterium Bacillus coagulans influences on the flavor of Gouda cheese using micro-cheese platform

Hyejin Choi,Sangdon Ryu,Daye Mun,Woongji Lee,An Na Kang,Mingeun Kang,Hayoung Kim,Daniel Lee,Sangnam Oh,Younghoon Kim 한국식품영양과학회 2021 한국식품영양과학회 학술대회발표집 Vol.2021 No.10

Bacillus coagulans is a gram-positive, spore-forming and potential probiotic bacterium in food industry. Spore-forming bacteria is enable to survive in the host"s gastrointestinal tract functioning as probiotics that could play a beneficial role in the host health. We evaluated the probiotic characteristics including acid, bile and heat tolerance of B. coagulans SRCM121381 isolated from human breast milk. SRCM121381 showed high resistance to acid and bile, heat tolerance. We employed FIMM (Fermentor for Intestine Microbiota Model) system to evaluate effects of SRCM 121381 on the microbial dynamics in gut environments. SRCM121381 resulted in increased population of Romboutsia and Turicibacter at the genus level, while the abundance of Escherichia decreased significantly. We added SRCM 121381 with starter strains for Gouda cheese using micro-cheese platform and evaluated on the change of cheese flavor. SRCM121381 increased acetic acid (Vinegar) and decreased esters and ketone as undesirable flavor such as bitter taste. Our results propose that potential probiotic bacterium B. coagulans SRCM121381 could be applied on dairy foods as an adjunct starter with flavor productivity.

Evaluation of Genetic Diversity and Population Structure Analysis among Germplasm of Agaricus bisporus by SSR Markers

( Hyejin An ),( Hwa-yong Lee ),( Hyeran Shin ),( Jun Hyoung Bang ),( Seahee Han ),( Youn-lee Oh ),( Kab-yeul Jang ),( Hyunwoo Cho ),( Tae Kyung Hyun ),( Jwakyung Sung ),( Yoon-sup So ),( Ick-hyun Jo ) 한국균학회 2021 Mycobiology Vol.49 No.4

Agaricus bisporus is a popular edible mushroom that is cultivated worldwide. Due to its secondary homothallic nature, cultivated A. bisporus strains have low genetic diversity, and breeding novel strains is challenging. The aim of this study was to investigate the genetic diversity and population structure of globally collected A. bisporus strains using simple sequence repeat (SSR) markers. Agaricus bisporus strains were divided based on genetic distance- based groups and model-based subpopulations. The major allele frequency (MAF), number of genotypes (NG), number of alleles (NA), observed heterozygosity (HO), expected heterozygosity (HE), and polymorphic information content (PIC) were calculated, and genetic distance, population structure, genetic differentiation, and Hardy-Weinberg equilibrium (HWE) were assessed. Strains were divided into two groups by distance-based analysis and into three subpopulations by model-based analysis. Strains in subpopulations POP A and POP B were included in Group I, and strains in subpopulation POP C were included in Group II. Genetic differentiation between strains was 99%. Marker AB-gSSR-1057 in Group II and subpopulation POP C was confirmed to be in HWE. These results will enhance A. bisporus breeding programs and support the protection of genetic resources.

MRI-Based Attenuation Correction for PET/MRI Using Multiphase Level-Set Method

An, Hyun Joon,Seo, Seongho,Kang, Hyejin,Choi, Hongyoon,Cheon, Gi Jeong,Kim, Han-Joon,Lee, Dong Soo,Song, In Chan,Kim, Yu Kyeong,Lee, Jae Sung Society of Nuclear Medicine 2016 The Journal of nuclear medicine Vol.57 No.4

<P>Inaccuracy in MR image-based attenuation correction (MR-AC) leads to errors in quantification and the misinterpretation of lesions in brain PET/MRI studies. To resolve this problem, we proposed an improved ultrashort echo time MR-AC method that was based on a multiphase level-set algorithm with main magnetic field (B-0) inhomogeneity correction. We also assessed the feasibility of this level-set-based MR-AC method (MR-AC(level)), compared with CT-AC and MR-AC provided by the manufacturer of the PET/MRI scanner (MR-AC(mMR)). Methods: Ten healthy volunteers and 20 Parkinson disease patients underwent F-18-FDG and F-18-fluorinated-N-3-fluoropropyl-2-beta-carboxymethoxy-3-beta-(4-iodophenyl)nortropane (F-18-FP-CIT) PET scans, respectively, using both PET/MRI and PET/CT scanners. The level-set-based segmentation algorithm automatically delimited air, bone, and soft tissue from the ultrashort echo time MR images. For the comparison, MR-AC maps were coregistered to reference CT. PET sinogram data obtained from PET/CT studies were then reconstructed using the CT-AC, MR-AC(mMR), and MR-AC(level) maps. The accuracies of SUV, SUVr (SUV and its ratio to the cerebellum), and specific-to-nonspecific binding ratios obtained using MR-AC(level) and MR-AC(mMR) were compared with CT-AC using region-of-interest-and voxel-based analyses. Results: There was remarkable improvement in the segmentation of air cavities and bones and the quantitative accuracy of PET measurement using the level set. Although the striatal and cerebellar activities in F-18-FP-CIT PET and frontal activity in F-18-FDG PET were significantly underestimated by the MR-AC(mMR), the MR-AC(level) provided PET images almost equivalent to the CT-AC images. PET quantification error was reduced by a factor of 3 using MR-AC(level) (SUV error < 10% in MR-AC(level) and < 30% in MR-AC(mMR) [version VB18P], and < 5% in MR-AC(level) and < 15% in MR-AC(mMR) [VB20P]). Conclusion: The results of this study indicate that our new multiphase level-set-based MR-AC method improves the quantitative accuracy of brain PET in PET/MRI studies.</P>

한국어 빈도 프로파일 구축 및 타당도 검증 연구

안혜진(Hyejin An) 국제한국어교육학회 2023 한국어 교육 Vol.34 No.2

The purpose of this study is to validate the Korean version of the Language Frequency Profile (KLFP) constructed using a vocabulary list. Through analysis of the KLFP in the writing of intermediate and advanced Korean learners, significant differences were found between the two groups. The same results were obtained when the intermediate and advanced groups were further subdivided. The findings indicate that learners with lower proficiency tended to use more frequent vocabulary (K1, K2), whereas those with higher proficiency tended to use more sophisticated vocabulary (KAWL, K3). However, when the learners' writing was controlled by topic, the intermediate and advanced groups could not be differentiated in detail, and the order of use of the frequency levels of the KLFP varied depending on the specific topic. Therefore, it was found that it is difficult to classify learners based solely on lexical sophistication. This study is the first in Korean language education to use a reference list to measure lexical sophistication, and it is meaningful in that it was able to identify how the pattern of vocabulary usage varies by KLFP depending on the learner's proficiency.

Development of an analytical algorithm for human O-GlcN acylation using LC-MS/MS

Dasom An,Hyejin Kim,Jin Young Kim,Jong Shin Yoo,Heeyoun Hwang 한국당과학회 2022 한국당과학회 학술대회 Vol.2022 No.07

O-GlcNAcylation is one of the post-translational modification that occurs at Ser/Thr residues of a protein by O-GlcNAc transferase (OGT), but the O-GlcNAcylation is regulated by O-GlcNAcase (OGA). The O-GlcNAcylation is involved in various cellular processes and diseases including diabetes, cancer and Alzheimer’s disease. Herein, we suggest a new method for identifying O-GlcNAcylated proteins including classification of O-GlcNAc and O-GalNAc with the same molecular weight. Using the fractionated raw files of LC-MS/MS from T24 cell lines, we developed an identification algorithm coded by python 3.9 as follows: 1.Selection of spectra with oxonium ions in ms2 file extracted from raw MS data obtained using LC-MS/MS; 2.Spectral matching with 20 ppm against a tryptic and O-GlcNAcylated peptide database generated from proteins identified using IP2 proteomic search result; 3.In the candidates, matching between tandem MS with b/y and c/z ion list and experimental HCD, ETD spectra, respectively; 4.Selection of the best scored O-GlcNAcylated peptide from the candidated peptides calculated by scoring system; 5.Classification of O-GlcNAc and O-GalNAc based on their corresponding fragment ions; 6.Evaluating a model using ROC curve comparing search results with manual validation. In addition, we also performed relative quantitative analysis in conjunction with the TMT Quantification method. In the glycoscience field, our study could be applied to various human disease treatments by identifying O-GlcNAcylated proteins and by engaging in cell signaling after regulating the function of them.