• Korean Journal of Clinical Laboratory Science
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• v.55 no.2
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• pp.93-104
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• 2023

This study aimed to identify new markers that cause lung adenocarcinoma by analyzing mutation hotspots for the top five genes with high mutation frequency in lung adenocarcinoma in Koreans by next generation sequencing (NGS) analysis. The association between TP53 mutation types and patterns with smoking, a major cause of lung cancer, was examined. The clinicopathological characteristics of lung adenocarcinoma patients with TP53 P72R SNPs were analyzed. In Korean lung adenocarcinoma cases, regardless of the smoking status, the TP53 P72R SNP was the most frequently occurring mutational hotspot, in which the nucleotide base was transversed from C to G, and the amino acid was substituted from proline to arginine at codon 72 of TP53. An analysis of the clinicopathological characteristics of lung adenocarcinoma cases with TP53 P72R SNP revealed no significant correlation with the patient's age, gender, smoking status, and tumor differentiation, but a significant correlation with low stage (P-value =0.026). This study confirmed an increase in TP53 rather than EGFR, which was reported as the most frequent mutations in lung adenocarcinoma in Koreans through NGS. Among them, TP53 P72R SNP is the most frequent regardless of smoking status.

• BMB Reports
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• v.56 no.10
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• pp.563-568
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• 2023

DNA methylation regulates gene expression and contributes to tumorigenesis in the early stages of cancer. In colorectal cancer (CRC), CpG island methylator phenotype (CIMP) is recognized as a distinct subset that is associated with specific molecular and clinical features. In this study, we investigated the genome-wide DNA methylation patterns among patients with CRC. The methylation data of 1 unmatched normal, 142 adjacent normal, and 294 tumor samples were analyzed. We identified 40,003 differentially methylated positions with 6,933 (79.8%) hypermethylated and 16,145 (51.6%) hypomethylated probes in the genic region. Hypermethylated probes were predominantly found in promoter-like regions, CpG islands, and N shore sites; hypomethylated probes were enriched in open-sea regions. CRC tumors were categorized into three CIMP subgroups, with 90 (30.6%) in the CIMP-high (CIMP-H), 115 (39.1%) in the CIMP-low (CIMP-L), and 89 (30.3%) in the non-CIMP group. The CIMP-H group was associated with microsatellite instability-high tumors, hypermethylation of MLH1, older age, and right-sided tumors. Our results showed that genome-wide methylation analyses classified patients with CRC into three subgroups according to CIMP levels, with clinical and molecular features consistent with previous data.

• Korean Journal of Clinical Laboratory Science
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• v.56 no.1
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• pp.10-20
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• 2024

RNA-sequencing (RNA-seq) is a technique used for providing global patterns of transcriptomes in samples. However, it can only provide the average gene expression across cells and does not address the heterogeneity within the samples. The advances in single-cell RNA sequencing (scRNA-seq) technology have revolutionized our understanding of heterogeneity and the dynamics of gene expression at the single-cell level. For example, scRNA-seq allows us to identify the cell types in complex tissues, which can provide information regarding the alteration of the cell population by perturbations, such as genetic modification. Since its initial introduction, scRNA-seq has rapidly become popular, leading to the development of a huge number of bioinformatic tools. However, the analysis of the big dataset generated from scRNA-seq requires a general understanding of the preprocessing of the dataset and a variety of analytical techniques. Here, we present an overview of the workflow involved in analyzing the scRNA-seq dataset. First, we describe the preprocessing of the dataset, including quality control, normalization, and dimensionality reduction. Then, we introduce the downstream analysis provided with the most commonly used computational packages. This review aims to provide a workflow guideline for new researchers interested in this field.

• International Journal of Heart Failure
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• v.6 no.3
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• pp.129-136
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• 2024

Background and Objectives: Heart failure (HF) is a leading cause of hospitalization and death worldwide. The Steady Movement with Innovating Leadership for Heart Failure (SMILE HF) aims to evaluate the clinical characteristics, management, hospital course, and long-term outcomes of patients hospitalized for acute HF in South Korea. Methods: This prospective, observational multicenter cohort study was conducted on consecutive patients hospitalized for acute HF in nine university hospitals since September 2019. Enrolment of 2000 patients should be completed in 2024, and follow-up is planned through 2025. Results: Interim analysis of 1,052 consecutive patients was performed to understand the baseline characteristics. The mean age was 69±15 years; 57.6% were male. The mean left ventricular ejection fraction was 39±15%. The prevalences of HF with reduced ejection fraction, HF with mildly reduced ejection fraction, and HF with preserved ejection fraction were 50.9%, 15.3%, and 29.2%. Ischemic cardiomyopathy (CMP) was the most common etiology (32%), followed by tachycardia-induced CMP (12.8%) and idiopathic dilated CMP (9.5%). The prescription rate of angiotensin-converting enzyme inhibitor/angiotensin receptor blockers/angiotensin receptor/neprilysin inhibitor, beta-blockers, spironolactone, and sodium-glucose cotransporter-2 inhibitors at discharge were 76.8%, 66.5%, 50.0%, and 17.5%, respectively. The post-discharge 90-day mortality and readmission rates due to HF aggravation were 2.0% and 6.4%, respectively. Our analysis reveals the current state of acute HF in South Korea. Conclusions: Our interim analysis provides valuable insights into the clinical characteristics, management, and early outcomes of acute HF patients in South Korea, highlighting the current state and treatment patterns in this population.

• Oncology Letters
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• v.42 no.1
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• pp.453-460
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• 2019

The present study aimed to identify novel methylation markers of clear cell renal cell carcinoma (ccRCC) using microarray methylation analysis and evaluate their prognostic relevance in patient samples. To identify cancer-specific methylated biomarkers, microarray profiling of ccRCC samples from our institute (n=12) and The Cancer Genome Atlas (TCGA) database (n=160) were utilized, and the prognostic relevance of candidate genes were investigated in another TCGA dataset (n=153). For validation, pyrosequencing analyses with ccRCC samples from our institute (n=164) and another (n=117) were performed and the potential clinical application of selected biomarkers was examined. We identified 22 CpG island loci that were commonly hypermethylated in ccRCC. Kaplan-Meier analysis of TCGA data indicated that only 4/22 loci were significantly associated with disease progression. In the internal validation set, Kaplan-Meier analysis revealed that hypermethylation of two loci, zinc finger protein 492 (ZNF492) and G protein-coupled receptor 149 (GPR149), was significantly associated with shorter time-to-progression. Multivariate Cox regression models revealed that hypermethylation of ZNF492 [hazard ratio (HR), 5.44; P=0.001] and GPR149 (HR, 7.07; P<0.001) may be independent predictors of tumor progression. Similarly, the methylation status of these two genes was significantly associated with poor outcomes in the independent external validation cohort. Collectively, the present study proposed that the novel methylation markers ZNF492 and GPR149 could be independent prognostic indicators in patients with ccRCC.

• Journal of the Health Care and Life Science
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• v.9 no.2
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• pp.303-308
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• 2021

Staphylococcus aureus and methicillin resistant S. aureus (MRSA) is a major cause of nosocomial infections and is one of the most commonly isolated bacterial species in the hospital and continues to be an important pathogens in both community and hospital-acquires infection. The purpose of this study is to investigate the carrier rate of S. aureus and MRSA in the community and molecular genetic characteristics of these organisms. The identification of S. aureus and MRSA were done by the procedures in Murray's manual of Clinical Microbiology and antibiotic susceptibility patterns by the Clinical and Laboratory Standards Institute(CLSI). MRSA strains were confirms by oxacillin disk diffusion method. forty-six strains (71.9%) of S. aureus were isolated from the nasal specimens of 64 students in health science university. twenty-two strains (22%) of 46 S. aureus were resistant to penicillin and oxacillin. twenty-two strains of the 46 S. aureus isolates were methicillin-resistant Staphylococcus aureus (MRSA). The mecA genes in MRSA were detected by polymerase chain reaction (PCR). Community and nosocomial infections caused by methicillin-resistant Staphylococcus aureus are a significant problem worldwide. There continuous epidemiological study is to investigate the prevalence of MRSA in community acquired infections.

• Radiation Oncology Journal
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• v.27 no.4
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• pp.201-209
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• 2009

Purpose: To investigate the care patterns for radiation therapy and to determine inter-hospital differences for patients with laryngeal carcinoma in Korea. Materials and Methods: A total of 237 cases of laryngeal carcinoma (glottis, 144; supraglottis, 93) assembled from 23 hospitals, who underwent irradiation in the year of 1998 and 1999, were retrospectively analyzed to investigate inter-hospital differences with respect to radiotherapy treatment. We grouped the 23 hospitals based on the number of new patients annually irradiated in 1998; and designated them as group A (${\geq}$900 patients), group B (${\geq}$400 patients and <900 patients), and group C (<400 patients). Results: The median age of the 237 patients was 62 years (range, 25 to 88 years), of which 216 were male and 21 were female. The clinical stages were distributed as follows: for glottis cancer, I; 61.8%, II; 21.5%, III; 4.2%, IVa; 11.1%, IVb; 1.4%, and in supraglottic cancer, I; 4.3%, II; 19.4%, III; 28.0%, IVa; 43.0%, IVb; 5.4%, respectively. Some differences were observed among the 3 groups with respect to the dose calculation method, radiation energy, field arrangement, and use of an immobilization device. No significant difference among 3 hospital groups was observed with respect to treatment modality, irradiation volume, and median total dose delivered to the primary site. Conclusion: This study revealed that radiotherapy process and patterns of care are relatively uniform in laryngeal cancer patients in Korean hospitals, and we hope this nationwide data can be used as a basis for the standardization of radiotherapy for the treatment of laryngeal cancer.

• Journal of Korean Physical Therapy Science
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• v.15 no.4
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• pp.35-42
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• 2008

Background : To assess the effect of a pelvic compression belt on the strength of hip flexor in healthy young individuals. Study design: Pre- and post-treatment measurement design on one factor was used. Methods : 30 healthy volunteers (male: 15, female: 15) participated in this study. Dynamometer was used to measure the strength of hip flexor, and measurements were performed before and after the application of the pelvic compression belt at neutral position of hip joint and at 30 cm raised position from floor with straight leg in supine. Results : After the application of the pelvic compression belt, the strengths of hip flexor measured at both positions were significantly increased when compared with before the application (p<.05). However, at neutral position of hip joint and at 30cm raised position from floor, there were significantly different in the changing patterns in the strengths of hip flexor between men and women (p>.05). Conclusion : The findings suggest that the pelvic compression belt is helpful in strengthening hip muscles. With easy application, it is sufficiently feasible for clinical use.

• Clinical and Experimental Reproductive Medicine
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• v.14 no.2
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• pp.109-118
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• 1987

Ninety-one patients with irreparable tubal disease underwent in Vitro Fertilization-Embryo Transfer (IVF-ET) in Seoul National University Hospital. Ovulation was stimulated in 104 cycles by human menopausal gonadotropin (HMG) or follicular stimulating hormone (FSH)/human chorionic gonadotropin (HCG). The patients were classified as high (>900 pg/ml), intermediate (400-900 pg/ml), or low (<400pg/ml) responder according to preovulatory $E_2$ response and four $E_2$ patterns were found. The overall pregnancy rate per cycle in this consecutive series was 11.5% (n=12). The number of preovulatory oocytes per cycle was higher significantly in intermediate and high responder group than in low responder group (P<0.01), While the number of immature oocytes per cycle significantly higher in low responder group than high and intermediate responder group (P<0.01). The pregnancy rate in each responder group was not signigicant. According to the $E_2$ pattern of response, there was no significant difference in number of the immature and preovulatory oocytes recovery per cycle. There was a apparently direct relationship between the preovulatory $E_2$ pattern and pre gnancy rate was noted.

• The Journal of Korean Society of Virology
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• v.26 no.2
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• pp.151-162
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• 1996

Pseudorabies is caused by Pseudorabies virus (PRV: Aujeszky's disease virus) of Herpesviridae that is characterized by 100 to 150nm in size with a linear double-stranded DNA molecule with of approximately $90{\times}10^6Da$. This disease affects most of domestic animals such as swine, cattle, dog, sheep, cat, chicken, etc. causing high mortality and economic losses. In swine, young piglets show high mortality and pregnant sows, reproductive failures. However the adult swine reveals no clinical signs in general. But they become a carrier state and play an important role for propagation of the disease. In this study, the nucleotide sequence of major casid protein gene of PRV, Yangsan strain isolated from the diseased swine in Korea was analyzed, and the recombinant MCP was produced by expression of the MCP gene in Sf-9 cell using baculovirus transfer vector system. As result, in BamHI digestion, MCP gene locus of PRV YS strain showed different from that of Indiana S strain. The patterns of enzyme mapping were also found to be unidentical each other. The sequence of the MCP gene partially analyzed showed 98.09% identity to Indiana S strain. The expression of MCP in Sf-9 cell cotransfected by pVLMCP-44 baculovirus expression vector was characterized by Southern blot hybridization, immunofluoresent and immunocytochemical tests, SDS-PAGE and Western blotting. The rMCP with M.W. 142kDa was most effectively expressed in Sf-9 cells at the 3-4th days post inoculation of the recombinant baculovirus by 2 moi.