97 results on '"Yejin Cho"'
Search Results
2. Role of histamine-mediated macrophage differentiation in clearance of metastatic bacterial infection
- Author
-
Kwang H. Kim, Donghwan Park, Soo Young Cho, Yejin Cho, Buhyun Lee, Haengdueng Jeong, Yura Lee, Yourim Lee, and Ki Taek Nam
- Subjects
histamine ,macrophage differentiation ,bacterial infection ,single-cell RNA sequencing ,peritoneal cells ,Immunologic diseases. Allergy ,RC581-607 - Abstract
Macrophages are highly heterogeneous immune cells with a role in maintaining tissue homeostasis, especially in activating the defense response to bacterial infection. Using flow cytometric and single-cell RNA-sequencing analyses of peritoneal cells, we here show that small peritoneal macrophage and immature macrophage populations are enriched in histamine-deficient (Hdc-/-) mice, characterized by a CD11bmiF4/80loCCR2+MHCIIhi and CD11bloF4/80miTHBS1+IL-1α+ phenotype, respectively. Molecular characterization revealed that immature macrophages represent an abnormally differentiated form of large peritoneal macrophages with strong inflammatory properties. Furthermore, deficiency in histamine signaling resulted in significant impairment of the phagocytic activity of peritoneal macrophage populations, conferring high susceptibility to bacterial infection. Collectively, this study reveals the importance of histamine signaling in macrophage differentiation at the molecular level to maintain tissue homeostasis, offering a potential therapeutic target for bacterial infection-mediated diseases.
- Published
- 2023
- Full Text
- View/download PDF
3. Role of Nox4 in Mitigating Inflammation and Fibrosis in Dextran Sulfate Sodium–Induced Colitis
- Author
-
Yura Lee, Sung-Hee Kim, Haengdueng Jeong, Kwang H. Kim, Donghun Jeon, Yejin Cho, Daekee Lee, and Ki Taek Nam
- Subjects
Fibrostenotic CD ,T-Cell Lineage Commitment ,RNA-Sequencing ,Oxidative Stress ,Diseases of the digestive system. Gastroenterology ,RC799-869 - Abstract
Background & Aims: Fibrosis development in ulcerative colitis is associated directly with the severity of mucosal inflammation, which increases the risk of colorectal cancer. The transforming growth factor-β (TGF-β) signaling pathway is an important source of tissue fibrogenesis, which is stimulated directly by reactive oxygen species produced from nicotinamide adenine dinucleotide phosphate oxidases (NOX). Among members of the NOX family, NOX4 expression is up-regulated in patients with fibrostenotic Crohn's disease (CD) and in dextran sulfate sodium (DSS)-induced murine colitis. The aim of this study was to determine whether NOX4 plays a role in fibrogenesis during inflammation in the colon using a mouse model. Methods: Acute and recovery models of colonic inflammation were performed by DSS administration to newly generated Nox4-/- mice. Pathologic analysis of colon tissues was performed, including detection of immune cells, proliferation, and fibrotic and inflammatory markers. RNA sequencing was performed to detect differentially expressed genes between Nox4-/- and wild-type mice in both the untreated and DSS-treated conditions, followed by functional enrichment analysis to explore the molecular mechanisms contributing to pathologic differences during DSS-induced colitis and after recovery. Results: Nox4-/- mice showed increased endogenous TGF-β signaling in the colon, increased reactive oxygen species levels, intensive inflammation, and an increased fibrotic region after DSS treatment compared with wild-type mice. Bulk RNA sequencing confirmed involvement of canonical TGF-β signaling in fibrogenesis of the DSS-induced colitis model. Up-regulation of TGF-β signaling affects collagen activation and T-cell lineage commitment, increasing the susceptibility for inflammation. Conclusions: Nox4 protects against injury and plays a crucial role in fibrogenesis in DSS-induced colitis through canonical TGF-β signaling regulation, highlighting a new treatment target.
- Published
- 2023
- Full Text
- View/download PDF
4. Histamine Signaling Is Essential for Tissue Macrophage Differentiation and Suppression of Bacterial Overgrowth in the StomachSummary
- Author
-
Kwang H. Kim, Jihwan Park, Yejin Cho, Soo Young Cho, Buhyun Lee, Haengdueng Jeong, Yura Lee, Ja-Woon Yi, Yeseul Oh, Jin-Jae Lee, Timothy C. Wang, Kyung-Min Lim, and Ki Taek Nam
- Subjects
Histidine Decarboxylase ,Macrophage ,Hypertrophic Gastropathy ,Stomach ,Diseases of the digestive system. Gastroenterology ,RC799-869 - Abstract
Background & Aims: Histamine in the stomach traditionally is considered to regulate acid secretion but also has been reported to participate in macrophage differentiation, which plays an important role in tissue homeostasis. Therefore, this study aimed to uncover the precise role of histamine in mediating macrophage differentiation and in maintaining stomach homeostasis. Methods: Here, we expand on this role using histidine decarboxylase knockout (Hdc-/-) mice with hypertrophic gastropathy. In-depth in vivo studies were performed in Hdc-/- mice, germ-free Hdc-/- mice, and bone-marrow–transplanted Hdc-/- mice. The stomach macrophage populations and function were characterized by flow cytometry. To identify stomach macrophages and find the new macrophage population, we performed single-cell RNA sequencing analysis on Hdc+/+ and Hdc-/- stomach tissues. Results: Single-cell RNA sequencing and flow cytometry of the stomach cells of Hdc-/- mice showed alterations in the ratios of 3 distinct tissue macrophage populations (F4/80+Il1bhigh, F4/80+CD93+, and F4/80-MHC class IIhighCD74high). Tissue macrophages of the stomachs of Hdc-/- mice showed impaired phagocytic activity, increasing the bacterial burden of the stomach and attenuating hypertrophic gastropathy in germ-free Hdc-/- mice. The transplantation of bone marrow cells of Hdc+/+ mice to Hdc-/- mice recovered the normal differentiation of stomach macrophages and relieved the hypertrophic gastropathy of Hdc-/- mice. Conclusions: This study showed the importance of histamine signaling in tissue macrophage differentiation and maintenance of gastric homeostasis through the suppression of bacterial overgrowth in the stomach.
- Published
- 2023
- Full Text
- View/download PDF
5. Gut microbiota of the young ameliorates physical fitness of the aged in mice
- Author
-
Kwang H. Kim, Yusook Chung, Ji-Won Huh, Dong Jin Park, Yejin Cho, Yeseul Oh, Haengdueng Jeong, Jaekyung Yoon, Ju-Hee Kang, Hae-Sol Shin, Hyoung-Chin Kim, Soon-Kyeong Kwon, Kyoung Yul Seo, Seung Hyun Oh, Je Kyung Seong, Sang-Jun Ha, Ki Taek Nam, and Jihyun F. Kim
- Subjects
Programmed aging ,C57BL/6 ,Microbiome ,Sarcopenia ,Ki-67 ,Microbial ecology ,QR100-130 - Abstract
Abstract Background Aging is a natural process that an organism gradually loses its physical fitness and functionality. Great efforts have been made to understand and intervene in this deteriorating process. The gut microbiota affects host physiology, and dysbiosis of the microbial community often underlies the pathogenesis of host disorders. The commensal microbiota also changes with aging; however, the interplay between the microbiota and host aging remains largely unexplored. Here, we systematically examined the ameliorating effects of the gut microbiota derived from the young on the physiology and phenotypes of the aged. Results As the fecal microbiota was transplanted from young mice at 5 weeks after birth into 12-month-old ones, the thickness of the muscle fiber and grip strength were increased, and the water retention ability of the skin was enhanced with thickened stratum corneum. Muscle thickness was also marginally increased in 25-month-old mice after transferring the gut microbiota from the young. Bacteria enriched in 12-month-old mice that received the young-derived microbiota significantly correlated with the improved host fitness and altered gene expression. In the dermis of these mice, transcription of Dbn1 was most upregulated and DBN1-expressing cells increased twice. Dbn1-heterozygous mice exhibited impaired skin barrier function and hydration. Conclusions We revealed that the young-derived gut microbiota rejuvenates the physical fitness of the aged by altering the microbial composition of the gut and gene expression in muscle and skin. Dbn1, for the first time, was found to be induced by the young microbiota and to modulate skin hydration. Our results provide solid evidence that the gut microbiota from the young improves the vitality of the aged. Video Abstract
- Published
- 2022
- Full Text
- View/download PDF
6. Sexually dimorphic leanness and hypermobility in p16 Ink4a /CDKN2A-deficient mice coincides with phenotypic changes in the cerebellum
- Author
-
Kwang H. Kim, Yejin Cho, Jaehoon Lee, Haengdueng Jeong, Yura Lee, Soo In Kim, Chang-Hoon Kim, Han-Woong Lee, and Ki Taek Nam
- Subjects
Medicine ,Science - Abstract
Abstract p16 Ink4a /CDKN2A is a tumor suppressor that critically regulates the cell cycle. Indeed, p16 Ink4a deficiency promotes tumor formation in various tissues. We now report that p16 Ink4a deficiency in female mice, but not male mice, induces leanness especially in old age, as indicated by lower body weight and smaller white adipose tissue, although other major organs are unaffected. Unexpectedly, the integrity, number, and sizes of adipocytes in white adipose tissue were unaffected, as was macrophage infiltration. Hence, hypermobility appeared to be accountable for the phenotype, since food consumption was not altered. Histological analysis of the cerebellum and deep cerebellar nuclei, a vital sensorimotor control center, revealed increased proliferation of neuronal cells and improved cerebellum integrity. Expression of estrogen receptor β (ERβ) and PCNA also increased in deep cerebellar nuclei, implying crosstalk between p16 Ink4a and ERβ. Furthermore, p16 Ink4a deficiency expands LC3B+ cells and GFAP+ astrocytes in response to estrogen. Collectively, the data suggest that loss of p16 INK4a induces sexually dimorphic leanness in female mice, which appears to be due to protection against cerebellar senescence by promoting neuronal proliferation and homeostasis via ERβ.
- Published
- 2019
- Full Text
- View/download PDF
7. Disruption of the Tff1 gene in mice using CRISPR/Cas9 promotes body weight reduction and gastric tumorigenesis
- Author
-
Hyejeong Kim, Haengdueng Jeong, Yejin Cho, Jaehoon Lee, Ki Taek Nam, and Han-Woong Lee
- Subjects
Tff1 ,gastric cancer ,CRISPR/Cas9 ,Tff1-knockout mouse ,Medicine (General) ,R5-920 ,Biology (General) ,QH301-705.5 - Abstract
Abstract Trefoil factor 1 (TFF1, also known as pS2) is strongly expressed in the gastrointestinal mucosa and plays a critical role in the differentiation of gastric glands. Since approximately 50% of all human gastric cancers are associated with decreased TFF1 expression, it is considered a tumor suppressor gene. Tff1 deficiency in mice results in histological changes in the antral and pyloric gastric mucosa, with severe hyperplasia and dysplasia of epithelial cells, resulting in the development of antropyloric adenoma. Here, we generated Tff1-knockout (KO) mice, without a neomycin resistant (NeoR) cassette, using the clustered regularly interspaced short palindromic repeats/CRISPR-associated nuclease 9 (CRSIPR/Cas9) system. Though our Tff1-KO mice showed phenotypes very similar to the previous embryonic stem (ES)-cell-based KO mice, they differed from the previous reports in that a reduction in body weight was observed in males. These results demonstrate that these newly established Tff1-KO mice are useful tools for investigating genetic and environmental factors influencing gastric cancer, without the effects of artificial gene insertion. Furthermore, these findings suggest a novel hypothesis that Tff1 expression influences gender differences.
- Published
- 2018
- Full Text
- View/download PDF
8. Lysates of a Probiotic, Lactobacillus rhamnosus, Can Improve Skin Barrier Function in a Reconstructed Human Epidermis Model
- Author
-
Ye-On Jung, Haengdueng Jeong, Yejin Cho, Eun-Ok Lee, Hye-Won Jang, Jinwook Kim, Ki Taek Nam, and Kyung-Min Lim
- Subjects
probiotic ,Lactobacillus rhamnosus ,skin barrier ,skin ,reconstructed human epidermis model ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The main function of the skin is to protect the body from the external environment. The barrier function of the skin is mainly provided by the stratum corneum, which consists of corneocytes bound with the corneodesmosomes and lamellar lipids. Skin barrier proteins like loricrin and filaggrin also contribute to the skin barrier function. In various skin diseases, skin barrier dysfunction is a common symptom, and skin irritants like detergents or surfactants could also perturb skin barrier function. Many efforts have been made to develop strategies to improve skin barrier function. Here, we investigated whether the microfluidized lysates of Lactobacillus rhamnosus (LR), one of the most widely used probiotic species for various health benefits, may improve the skin barrier function in a reconstructed human epidermis, Keraskin™. Application of LR lysate on Keraskin™ increased the expression of tight junction proteins; claudin 1 and occludin as determined by immunofluorescence analysis, and skin barrier proteins; loricrin and filaggrin as determined by immunohistochemistry and immunofluorescence analysis and qPCR. Also, the cytotoxicity of a skin irritant, sodium lauryl sulfate (SLS), was alleviated by the pretreatment of LR lysate. The skin barrier protective effects of LR lysate could be further demonstrated by the attenuation of SLS-enhanced dye-penetration. LR lysate also attenuated the destruction of desmosomes after SLS treatment. Collectively, we demonstrated that LR lysate has protective effects on the skin barrier, which could expand the utility of probiotics to skin-moisturization ingredients.
- Published
- 2019
- Full Text
- View/download PDF
9. Disentangling Structure and Style: Political Bias Detection in News by Inducing Document Hierarchy.
- Author
-
Jiwoo Hong, Yejin Cho, Jiyoung Han, Jaemin Jung, and James Thorne
- Published
- 2023
- Full Text
- View/download PDF
10. Broadcasting in Vehicular Ad-hoc Network: Survey on Recent Advances.
- Author
-
Yejin Cho, Mingyu Park, and Jeongyeup Paek
- Published
- 2022
- Full Text
- View/download PDF
11. Prometheus: Inducing Fine-grained Evaluation Capability in Language Models.
- Author
-
Seungone Kim, Jamin Shin, Yejin Cho, Joel Jang, Shayne Longpre, Hwaran Lee, Sangdoo Yun, Seongjin Shin, Sungdong Kim, James Thorne, and Minjoon Seo
- Published
- 2023
- Full Text
- View/download PDF
12. Therapeutic delivery of CCL2 modulates immune response and restores host-microbe homeostasis.
- Author
-
Shehabeldin, Mostafa, Jin Gao, Yejin Cho, Rong Chong, Tabib, Tracy, Lu Li, Smardz, Matthew, Gaffen, Sarah L., Diaz, Patricia I., Lafyatis, Robert, Little, Steven R., and Sfeir, Charles
- Subjects
RNA ,ORAL microbiology ,PROTEIN kinases ,HOMEOSTASIS ,PERIODONTAL disease - Abstract
Many chronic inflammatory diseases are attributed to disturbances in host-microbe interactions, which drive immune-mediated tissue damage. Depending on the anatomic setting, a chronic inflammatory disease can exert unique local and systemic influences, which provide an exceptional opportunity for understanding disease mechanism and testing therapeutic interventions. The oral cavity is an easily accessible environment that allows for protective interventions aiming at modulating the immune response to control disease processes driven by a breakdown of host-microbe homeostasis. Periodontal disease (PD) is a prevalent condition in which quantitative and qualitative changes of the oral microbiota (dysbiosis) trigger nonresolving chronic inflammation, progressive bone loss, and ultimately tooth loss. Here, we demonstrate the therapeutic benefit of local sustained delivery of the myeloid-recruiting chemokine (C-C motif) ligand 2 (CCL2) in murine ligature-induced PD using clinically relevant models as a preventive, interventional, or reparative therapy. Local delivery of CCL2 into the periodontium inhibited bone loss and accelerated bone gain that could be ascribed to reduced osteoclasts numbers. CCL2 treatment up-regulated M2-macrophage and downregulated proinflammatory and pro-osteoclastic markers. Furthermore, single-cell ribonucleic acid (RNA) sequencing indicated that CCL2 therapy reversed disease-associated transcriptomic profiles of murine gingival macrophages via inhibiting the triggering receptor expressed on myeloid cells-1 (TREM-1) signaling in classically activated macrophages and inducing protein kinase A (PKA) signaling in infiltrating macrophages. Finally, 16S ribosomal ribonucleic acid (rRNA) sequencing showed mitigation of microbial dysbiosis in the periodontium that correlated with a reduction in microbial load in CCL2-treated mice. This study reveals a novel protective effect of CCL2 local delivery in PD as a model for chronic inflammatory diseases caused by a disturbance in host-microbe homeostasis. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
13. Leveraging WordNet Paths for Neural Hypernym Prediction.
- Author
-
Yejin Cho, Juan Diego Rodriguez, Yifan Gao, and Katrin Erk
- Published
- 2020
- Full Text
- View/download PDF
14. Role of histamine-mediated macrophage differentiation in clearance of metastatic bacterial infection.
- Author
-
Kim, Kwang H., Donghwan Park, Soo Young Cho, Yejin Cho, Buhyun Lee, Haengdueng Jeong, Yura Lee, Yourim Lee, and Ki Taek Nam
- Subjects
BACTERIAL diseases ,PERITONEAL macrophages ,MACROPHAGES ,CELL analysis ,METASTASIS - Abstract
Macrophages are highly heterogeneous immune cells with a role in maintaining tissue homeostasis, especially in activating the defense response to bacterial infection. Using flow cytometric and single-cell RNA-sequencing analyses of peritoneal cells, we here show that small peritoneal macrophage and immature macrophage populations are enriched in histamine-deficient (Hdc
-/- ) mice, characterized by a CD11bmi F4/80lo CCR2+ MHCIIhi and CD11blo F4/80mi THBS1+ IL-1α+ phenotype, respectively. Molecular characterization revealed that immature macrophages represent an abnormally differentiated form of large peritoneal macrophages with strong inflammatory properties. Furthermore, deficiency in histamine signaling resulted in significant impairment of the phagocytic activity of peritoneal macrophage populations, conferring high susceptibility to bacterial infection. Collectively, this study reveals the importance of histamine signaling in macrophage differentiation at the molecular level to maintain tissue homeostasis, offering a potential therapeutic target for bacterial infection-mediated diseases. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
15. The Parallel Multiple Mediating Effects of Work-Family Conflict and Loneliness in the Relationship between Temperaments, Depression, and Anxiety while Working from Home
- Author
-
Yeeun Hwang, Yejin Cho, Yuseung Choi, and Myoung-Ho Hyun
- Abstract
Background: As the number of people working from home has increased since the COVID-19 pandemic, it is important to understand workers’ stress and psychological state while working from home. Work-family conflict and loneliness may be related to working from home, and they could be experienced differently depending on individual traits. Therefore, this study examined the parallel multiple mediating effects of work-family conflict and loneliness in the relationship between personal temperaments and negative emotions such as depression and anxiety.Methods: Data were collected online from people currently working from home for at least one month, more than once per week. They answered K-DASS-21, UCLA loneliness scale, Work-Family Conflict, and FCB-TI. Only four temperaments were used in the statistic step: Briskness and Sense sensitivity as protective factors and Perseveration and Emotional reactivity as vulnerable factors. The multiple mediating effects were analyzed independently by using the PROCESS macro.Results: Firstly, Briskness and Sense sensitivity were found to negatively affect depression and anxiety while working from home by significantly mediating work-family conflict and loneliness. Thus, these temperaments would be protective factors while working from home. Secondly, Perseveration and Emotional reactivity positively influenced both negative emotions by mediating two mediation variables, which means that both temperaments are vulnerable factors.Conclusions: The results suggest that personality traits can impact how people experience stress and negative emotions in working situations, leading to negative psychological states. Consequently, personal temperaments would be important to understand relationships between environments and internal experiences.
- Published
- 2022
16. Time Management, Quality of Life, and Work-Life Balance Based on Temperament of Workers
- Author
-
Yuseung Choi, Yejin Cho, Yeeun Hwang, and Myoung-Ho Hyun
- Abstract
Background: Temperament plays an important role in adapting to different environments. The purpose of this study is to investigate the differences between temperament clusters, time management behavior, quality of life, and work-life balance.Methods: A total of 216 participants (male=56, female=160, mean age: 31.92 years) completed questionnaires measuring temperament, time management behavior, quality of life, and work-life balance.Results: Data from the study shows that temperamental profiles are classified into three groups. The profile of “Adaptive Solver” was associated with the most beneficial traits, and that of “Chronic Worrier” was associated with the most disadvantageous traits.Conclusions: The findings of this study confirm that temperaments are related to psychological adjustment. This study provides an implication for considering individual differences in the intervention for psychological adaptation of workers.
- Published
- 2022
17. Monitoring a tumor-targeting BODIPY-based theranostic nanomaterial with photoacoustic imaging
- Author
-
Sinyoung Park, Eun-Yeong Park, Nahyun Kwon, Kwang H. Kim, Yejin Cho, Junha Lim, Seda Çetindere, Süreyya O. Tümay, Wonjong Kim, Xingshu Li, Ki Taek Nam, Serkan Yeşilot, Juyoung Yoon, and Chulhong Kim
- Published
- 2023
18. Myelin Water Imaging of Nerve Recovery in Rehabilitating Stroke Patients
- Author
-
Muyul Park, Yejin Cho, Dae Hyun Kim, Hyun Seok Choi, Dong‐Hyun Kim, and Deog Young Kim
- Subjects
Male ,Stroke ,Anisotropy ,Humans ,Water ,Female ,Radiology, Nuclear Medicine and imaging ,Magnetic Resonance Imaging ,Myelin Sheath - Abstract
Myelin water imaging (MWI) using MRI has been introduced as a method to quantify the integrity of myelin in vivo. However, the investigation of its potential to probe myelin changes has been limited.To determine the myelin change using MWI in the corticospinal tract (CST) during the rehabilitation of stroke patients.Longitudinal.A total of 24 stroke patients within 6 months from the onset (64.3 ± 16.1 years, 14 women, 10 men) and 10 healthy volunteers (27.0 ± 2.2 years, 2 women, 8 men).Three-dimensional multiecho gradient echo sequence and diffusion-weighted echoplanar imaging sequence at 3 T.The changes of myelin water fraction (MWF) and fractional anisotropy (FA) during rehabilitation were analyzed in the CST and other regions using tractography software and region of interest drawings by the radiologist.A paired t-test was performed to investigate the change of MRI metrics during rehabilitation. In addition, an independent two-sample t-test was performed to investigate the effects of different rehabilitation protocols. A P-value0.05 was considered significant.In the CST, MWF significantly changed from 5.83 ± 0.91% to 6.23 ± 0.97% after rehabilitation while changes of FA (0.442 ± 0.038 to 0.443 ± 0.035) were not significant (P = 0.656). The rate of change in MWF and FA, which were 6.69% and 0.439% respectively, were significantly different. Other regions did not show significant changes (range of MWF change: -3.44% to -1.61%, range of FA change: -1.39% to 0.79%, and range of P-value: 0.144-0.761). Further analysis showed that those with additional robot-assisted rehabilitation had a significantly larger MWF change than those with conventional rehabilitation only (rate of change: 11.2% vs. 3.2%).The feasibility of using MWI to monitor myelin content was demonstrated by showing the MWF changes during rehabilitation.2 TECHNICAL EFFICACY STAGE: 2.
- Published
- 2022
19. A New Murine Liver Fibrosis Model Induced by Polyhexamethylene Guanidine-Phosphate
- Author
-
Ki Taek Nam, Yejin Cho, Minjeong Kim, Keunyoung Kim, Ha Ryong Kim, Kwang H. Kim, Kyung Min Lim, and Sumin Hur
- Subjects
Pharmacology ,Pathology ,medicine.medical_specialty ,Cirrhosis ,Lumican ,business.industry ,medicine.disease ,Biochemistry ,Pathogenesis ,Downregulation and upregulation ,Fibrosis ,In vivo ,Hepatocellular carcinoma ,Drug Discovery ,medicine ,Molecular Medicine ,Wound healing ,business - Abstract
Liver fibrosis is part of the wound healing process to help the liver recover from the injuries caused by various liver-damaging insults. However, liver fibrosis often progresses to life-threatening cirrhosis and hepatocellular carcinoma. To overcome the limitations of current in vivo liver fibrosis models for studying the pathophysiology of liver fibrosis and establishing effective treatment strategies, we developed a new mouse model of liver fibrosis using polyhexamethylene guanidine phosphate (PHMG-p), a humidifier sterilizer known to induce lung fibrosis in humans. Male C57/BL6 mice were intraperitoneally injected with PHMG-p (0.03% and 0.1%) twice a week for 5 weeks. Subsequently, liver tissues were examined histologically and RNA-sequencing was performed to evaluate the expression of key genes and pathways affected by PHMG-p. PHMG-p injection resulted in body weight loss of ~15% and worsening of physical condition. Necropsy revealed diffuse fibrotic lesions in the liver with no effect on the lungs. Histology, collagen staining, immunohistochemistry for smooth muscle actin and collagen, and polymerase chain reaction analysis of fibrotic genes revealed that PHMG-p induced liver fibrosis in the peri-central, peri-portal, and capsule regions. RNA-sequencing revealed that PHMG-p affected several pathways associated with human liver fibrosis, especially with upregulation of lumican and IRAK3, and downregulation of GSTp1 and GSTp2, which are closely involved in liver fibrosis pathogenesis. Collectively we demonstrated that the PHMG-p-induced liver fibrosis model can be employed to study human liver fibrosis.
- Published
- 2022
20. Exploring the multifaceted factors affecting pork meat quality
- Author
-
Sriniwas Pandey, Sheena Kim, Eun Sol Kim, Gi Beom Keum, Hyunok Doo, Jinok Kwak, Sumin Ryu, Yejin Choi, Juyoun Kang, Haram Kim, Yeongjae Chae, Kuk-Hwan Seol, Sun Moon Kang, Yunseok Kim, Pil Nam Seong, In-Seon Bae, Soo-Hyun Cho, Samooel Jung, and Hyeun Bum Kim
- Subjects
Pig ,Meat quality ,Pork ,Animal culture ,SF1-1100 - Abstract
The significance of pork meat quality extends far beyond mere consumer satisfaction, encompassing crucial aspects such as health and nutrition, economic impact, reputation and branding, food safety, and sustainability within the global food system. Influenced by a multitude of factors, each playing a pivotal role in shaping its sensory attributes and consumer appeal, pork meat quality stands as a cornerstone of the meat industry. Thus, understanding these factors are imperative for ensuring consistent high-quality pork production, aligning with consumer preferences, and elevating overall satisfaction levels. In this review, we provide a comprehensive overview of the diverse factors affecting pork meat quality, including genetic characteristics, rearing systems, feed composition, gender differences, pre-slaughter handling, and meat aging processes.
- Published
- 2024
- Full Text
- View/download PDF
21. Investigation of the impact of multi-strain probiotics containing Saccharomyces cerevisiae on porcine production
- Author
-
Sheena Kim, Jinho Cho, Gi Beom Keum, Jinok Kwak, Hyunok Doo, Yejin Choi, Juyoun Kang, Haram Kim, Yeongjae Chae, Eun Sol Kim, Minho Song, and Hyeun Bum Kim
- Subjects
Complex probiotics ,Growth performance ,Gut health ,Saccharomyces cerevisiae ,Swine ,Animal culture ,SF1-1100 - Abstract
A balanced intestinal microbiome controls intestinal bacterial diseases, helps regulate immunity, and digests and utilizes nutrients, ultimately having a positive effect on the productivity of industrial animals. Yeasts help in the digestion process by breaking down indigestible fibers and producing organic acids, vitamins, and minerals. In particular, polysaccharides such as beta-glucan and mannan-oligosaccharides, which are present in the cell wall of yeast, inhibit the adhesion of pathogens to the surface of the gastrointestinal tract and increase resistance to disease to help maintain and improve intestinal health. Among the yeast additives used in animal feed, Saccharomyces cerevisiae is one of the most commonly used probiotics. However, it does not naturally reside in the intestine, so if it is supplied in combination with other species of probiotics that can compensate for it, many benefits and synergies can be expected for pigs in terms of maintaining intestinal health such as supplementing the immune system and improving digestion. A number of previous studies have demonstrated that dietary complex probiotic supplementation has growth-promoting effects in pigs, suggesting that multiple strains of probiotics may be more effective than single strain probiotics due to their additive and synergistic effects. In practice, however, the effects of complex probiotics are not always consistent, and can be influenced by a variety of factors. Therefore, this review comprehensively examines and discusses the literature related to the effects of complex probiotics using Saccharomyces cerevisiae in pig production.
- Published
- 2024
- Full Text
- View/download PDF
22. Electric Conductivity Study of Cu Composite Reinforced by 3-dimensional Graphene
- Author
-
Chang Hoon LEE, Byung Sang CHOI, and YeJin CHO
- Subjects
General Physics and Astronomy - Published
- 2022
23. SIGCHI extended abstracts: gravity of light.
- Author
-
Younghui Kim and Yejin Cho
- Published
- 2013
- Full Text
- View/download PDF
24. Human gastric microbiota transplantation recapitulates premalignant lesions in germ-free mice
- Author
-
Jun Chul Park, Buhyun Lee, Ki Taek Nam, So Dam Lee, Jin-Jae Lee, Jihyun F. Kim, Jaekyung Yoon, Yusook Chung, Sung-Hee Kim, Soon Kyeong Kwon, Kwang H. Kim, Yong Chan Lee, Yejin Cho, Bo Ram Hwang, Haengdueng Jeong, and Yeseul Oh
- Subjects
Pathology ,medicine.medical_specialty ,biology ,digestive, oral, and skin physiology ,Gastroenterology ,Cancer ,Intestinal metaplasia ,Helicobacter pylori ,biology.organism_classification ,medicine.disease ,digestive system diseases ,Transplantation ,Gastric Dysplasia ,Dysplasia ,medicine ,Microbiome ,Antrum - Abstract
ObjectiveGastric cancer (GC) is a leading cause of cancer-related mortality. Although microbes besides Helicobacter pylori may also contribute to gastric carcinogenesis, wild-type germ-free (GF) mouse models investigating the role of human gastric microbiota in the process are not yet available. We aimed to evaluate the histopathological features of GF mouse stomachs transplanted with gastric microbiota from patients with different gastric disease states and their relationships with the microbiota.DesignMicrobiota profiles in corpus and antrum tissues and gastric fluid from 12 patients with gastric dysplasia or GC were analysed. Thereafter, biopsied corpus and antrum tissues and gastric fluid from patients (n=15 and n=12, respectively) with chronic superficial gastritis, intestinal metaplasia or GC were inoculated into 42 GF C57BL/6 mice. The gastric microbiota was analysed by amplicon sequencing. Histopathological features of mouse stomachs were analysed immunohistochemically at 1 month after inoculation. An independent set of an additional 15 GF mice was also analysed at 1 year.ResultsThe microbial community structures of patients with dysplasia or GC in the corpus and antrum were similar. The gastric microbiota from patients with intestinal metaplasia or GC selectively colonised the mouse stomachs and induced premalignant lesions: loss of parietal cells and increases in inflammation foci, in F4/80 and Ki-67 expression, and in CD44v9/GSII lectin expression. Marked dysplastic changes were noted at 1 year post inoculation.ConclusionMajor histopathological features of premalignant changes are reproducible in GF mice transplanted with gastric microbiota from patients with intestinal metaplasia or GC. Our results suggest that GF mice are useful for analysing the causality of associations reported in human gastric microbiome studies.
- Published
- 2021
25. Helicobacter pylori promotes epithelial-to-mesenchymal transition by downregulating CK2β in gastric cancer cells
- Author
-
So Dam Lee, Haengdueng Jeong, Bo Ram Hwang, Byeong Min Yu, Yejin Cho, Ki Teak Nam, Hyunki Kim, and Yong Chan Lee
- Subjects
Molecular Medicine ,Molecular Biology - Abstract
Strains of Helicobacter pylori that are positive for the oncoprotein CagA (cytotoxin-associated gene A) are associated with gastric cancer and might be related to the epithelial-to-mesenchymal transition (EMT). Casein kinase 2 (CK2) is a serine/threonine protein kinase that plays a major role in tumorigenesis through signaling pathways related to the EMT. However, the role played by the interaction between CagA and CK2 in gastric carcinogenesis is poorly understood. Although CK2α protein expression remained unchanged during H. pylori infection, we found that CK2α kinase activity was increased in gastric epithelial cells. We also found that the CK2β protein level decreased in H. pylori-infected gastric cancer cells in CagA-dependent manner and demonstrated that CagA induced CK2β degradation via HDM2 (human double minute 2; its murine equivalent is MDM2). We observed that CagA induced HDM2 protein phosphorylation and that p53 levels were decreased in H. pylori-infected gastric cancer cells. In addition, downregulation of CK2β induced AKT Ser473 phosphorylation and decreased the AKT Ser129 phosphorylation level in gastric cancer cells. We also found that the downregulation of CK2β triggered the upregulation of Snail levels in gastric cancer cells. Furthermore, our in vivo experiments and functional assays of migration and colony formation suggest that CK2β downregulation is a major factor responsible for the EMT in gastric cancer. Therefore, CK2 could be a key mediator of the EMT in H. pylori-infected gastric cancer and could serve as a molecular target for gastric cancer treatment.
- Published
- 2022
26. Identification of gaze pattern and blind spots by upper gastrointestinal endoscopy using an eye-tracking technique
- Author
-
Hyunsoo Chung, Soo-Jeong Cho, Ayoung Lee, Yejin Cho, Eunwoo Lee, Sang Gyun Kim, Jinju Choi, Bokyung Kim, and Jue Lie Kim
- Subjects
medicine.medical_specialty ,genetic structures ,medicine.diagnostic_test ,Esophagogastroduodenoscopy ,business.industry ,Blind spot ,Upper gastrointestinal endoscopy ,Gaze ,03 medical and health sciences ,0302 clinical medicine ,030220 oncology & carcinogenesis ,Ophthalmology ,Distraction ,Fixation (visual) ,medicine ,Eye tracking ,030211 gastroenterology & hepatology ,Surgery ,Esophagogastric junction ,business - Abstract
The lesion detection rate of esophagogastroduodenoscopy (EGD) varies depending on the degree of experience of the endoscopist and anatomical blind spots. This study aimed to identify gaze patterns and blind spots by analyzing the endoscopist’s gaze during real-time EGD. Five endoscopists were enrolled in this study. The endoscopist’s eye gaze tracked by an eye tracker was selected from the esophagogastric junction to the second portion of the duodenum without the esophagus during insertion and withdrawal, and then matched with photos. Gaze patterns were visualized as a gaze plot, blind spot detection as a heatmap, observation time (OT), fixation duration (FD), and FD-to-OT ratio. The mean OT and FD were 11.10 ± 11.14 min and 8.37 ± 9.95 min, respectively, and the FD-to-OT ratio was 72.5%. A total of 34.3% of the time was spent observing the antrum. When observing the body of the stomach, it took longer to observe the high body in the retroflexion view and the low-to-mid body in the forward view. It is necessary to minimize gaze distraction and observe the posterior wall in the retroflexion view. Our results suggest that eye-tracking techniques may be useful for future endoscopic training and education.
- Published
- 2021
27. Hexa-BODIPY-cyclotriphosphazene based nanoparticle for NIR fluorescence/photoacoustic dual-modal imaging and photothermal cancer therapy
- Author
-
Nahyun Kwon, Kwang H. Kim, Sinyoung Park, Yejin Cho, Eun-Yeong Park, Junha Lim, Seda Çetindere, Süreyya Oğuz Tümay, Won Jong Kim, Xingshu Li, Ki Taek Nam, Chulhong Kim, Serkan Yeşilot, and Juyoung Yoon
- Subjects
Boron Compounds ,Optical Imaging ,Biomedical Engineering ,Biophysics ,General Medicine ,Biosensing Techniques ,Theranostic Nanomedicine ,Photoacoustic Techniques ,Mice ,Hexosaminidase A ,Cell Line, Tumor ,Neoplasms ,Electrochemistry ,Animals ,Nanoparticles ,Reactive Oxygen Species ,Biotechnology - Abstract
Theranostic, which integrates the diagnosis and tumor treatment in tandem, is an emerging strategy in cancer treatment. Here, we report a novel and unique theranostic nanoparticle, HBCP NP, based on hexa-BODIPY cyclophosphazene (HBCP). Due to the unique bulky molecular structure of HBCP, this nanoparticle can simultaneously perform near-infrared (NIR) fluorescence imaging and photoacoustic imaging (PAI). Interestingly, since reactive oxygen species (ROS) generation of HBCP NPs is completely inhibited, 'safe' fluorescence imaging is possible without the risk of cell damage even under laser irradiation. Finally, NIR fluorescence imaging and PAI in 4T1 tumor-bearing mice demonstrated selective accumulation of HBCP NPs at tumor sites. In addition, HBCP NPs exhibited excellent photothermal effects under high-power laser irradiation, achieving effective tumor growth inhibition.
- Published
- 2022
28. High production of ectoine from methane in genetically engineered Methylomicrobium alcaliphilum 20Z by preventing ectoine degradation
- Author
-
Sang Eun Lim, Sukhyeong Cho, Yejin Choi, Jeong-Geol Na, and Jinwon Lee
- Subjects
Methane ,Methanotroph ,Ectoine ,Methylomicrobium alcaliphilum 20Z ,Nitrogen source ,Microbiology ,QR1-502 - Abstract
Abstract Background Methane is a greenhouse gas with a significant potential to contribute to global warming. The biological conversion of methane to ectoine using methanotrophs represents an environmentally and economically beneficial technology, combining the reduction of methane that would otherwise be combusted and released into the atmosphere with the production of value-added products. Results In this study, high ectoine production was achieved using genetically engineered Methylomicrobium alcaliphilum 20Z, a methanotrophic ectoine-producing bacterium, by knocking out doeA, which encodes a putative ectoine hydrolase, resulting in complete inhibition of ectoine degradation. Ectoine was confirmed to be degraded by doeA to N-α-acetyl-L-2,4-diaminobutyrate under nitrogen depletion conditions. Optimal copper and nitrogen concentrations enhanced biomass and ectoine production, respectively. Under optimal fed-batch fermentation conditions, ectoine production proportionate with biomass production was achieved, resulting in 1.0 g/L of ectoine with 16 g/L of biomass. Upon applying a hyperosmotic shock after high–cell–density culture, 1.5 g/L of ectoine was obtained without further cell growth from methane. Conclusions This study suggests the optimization of a method for the high production of ectoine from methane by preventing ectoine degradation. To our knowledge, the final titer of ectoine obtained by M. alcaliphilum 20ZDP3 was the highest in the ectoine production from methane to date. This is the first study to propose ectoine production from methane applying high cell density culture by preventing ectoine degradation.
- Published
- 2024
- Full Text
- View/download PDF
29. Elevated GCN5 expression confers tamoxifen resistance by upregulating AIB1 expression in ER-positive breast cancer
- Author
-
Clara Yuri Kim, Ki Taek Nam, Ji Hoon Oh, Kwang H. Kim, Myoung Hee Kim, Yejin Cho, Da Som Jeong, and Ji-Yeon Lee
- Subjects
0301 basic medicine ,Drug ,Cancer Research ,media_common.quotation_subject ,Estrogen receptor ,Breast Neoplasms ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Breast cancer ,Downregulation and upregulation ,In vivo ,Cell Line, Tumor ,Animals ,Humans ,Medicine ,p300-CBP Transcription Factors ,skin and connective tissue diseases ,media_common ,biology ,Effector ,business.industry ,Histone acetyltransferase ,Prognosis ,medicine.disease ,Up-Regulation ,DNA-Binding Proteins ,Gene Expression Regulation, Neoplastic ,Tamoxifen ,enzymes and coenzymes (carbohydrates) ,030104 developmental biology ,Receptors, Estrogen ,Oncology ,Drug Resistance, Neoplasm ,030220 oncology & carcinogenesis ,MCF-7 Cells ,Cancer research ,biology.protein ,Female ,Tumor Suppressor Protein p53 ,business ,Neoplasm Transplantation ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug - Abstract
Approximately 70% of breast cancers are estrogen receptor (ER)-positive and treated with endocrine therapy. A commonly used treatment agent, tamoxifen, shows high efficacy for improving prognosis. However, approximately one-third of patients treated with tamoxifen develop resistance to this drug. Here, we investigated the function of general control non-derepressible 5 (GCN5) and its downstream effectors in tamoxifen-resistant (TamR) breast cancer. TamR-MCF7 breast cancer cells maintained high GCN5 levels due to its attenuated proteasomal degradation. GCN5 overexpression upregulated amplified in breast cancer 1 (AIB1) expression, resulting in decreased p53 stability and tamoxifen resistance. Conversely, the sensitivity of GCN5-AIB1-overexpressing MCF7 cells to tamoxifen was restored by forced p53 expression. An in vivo study demonstrated a positive correlation between GCN5 and AIB1 and their contribution to tamoxifen resistance. We concluded that GCN5 promotes AIB1 expression and tamoxifen resistance in breast cancer by reducing p53 levels, suggesting the utility of GCN5 and its downstream effectors as therapeutic targets to either prevent or overcome tamoxifen resistance in breast cancer.
- Published
- 2020
30. Reactivity Differences Enable ROS for Selective Ablation of Bacteria
- Author
-
Xiaofeng Wu, Mengyao Yang, Ji Seon Kim, Rui Wang, Gyoungmi Kim, Jeongsun Ha, Heejeong Kim, Yejin Cho, Ki Taek Nam, and Juyoung Yoon
- Subjects
Mice ,Photosensitizing Agents ,Bacteria ,Photochemotherapy ,Gram-Negative Bacteria ,Animals ,General Chemistry ,General Medicine ,Gram-Positive Bacteria ,Reactive Oxygen Species ,Catalysis ,Anti-Bacterial Agents - Abstract
An effective strategy to engineer selective photodynamic agents to surmount bacterial-infected diseases, especially Gram-positive bacteria remains a great challenge. Herein, we developed two examples of compounds for a proof-of-concept study where reactive differences in reactive oxygen species (ROS) can induce selective ablation of Gram-positive bacteria. Sulfur-replaced phenoxazinium (NBS-N) mainly generates a superoxide anion radical capable of selectively killing Gram-positive bacteria, while selenium-substituted phenoxazinium (NBSe-N) has a higher generation of singlet oxygen that can kill both Gram-positive and Gram-negative bacteria. This difference was further evidenced by bacterial fluorescence imaging and morphological changes. Moreover, NBS-N can also successfully heal the Gram-positive bacteria-infected wounds in mice. We believe that such reactive differences may pave a general way to design selective photodynamic agents for ablating Gram-positive bacteria-infected diseases.
- Published
- 2022
31. Antibiotic resistance in livestock, environment and humans: One Health perspective
- Author
-
Sriniwas Pandey, Hyunok Doo, Gi Beom Keum, Eun Sol Kim, Jinok Kwak, Sumin Ryu, Yejin Choi, Juyoun Kang, Sheena Kim, Na Rae Lee, Kwang Kyo Oh, Ju-Hoon Lee, and Hyeun Bum Kim
- Subjects
Antibiotic resistance ,Livestock ,Human ,Environment ,One Health ,Animal culture ,SF1-1100 - Abstract
Antibiotic resistance (AR) is a complex, multifaceted global health issue that poses a serious threat to livestock, humans, and the surrounding environment. It entails several elements and numerous potential transmission routes and vehicles that contribute to its development and spread, making it a challenging issue to address. AR is regarded as an One Health issue, as it has been found that livestock, human, and environmental components, all three domains are interconnected, opening up channels for transmission of antibiotic resistant bacteria (ARB). AR has turned out to be a critical problem mainly because of the overuse and misuse of antibiotics, with the anticipation of 10 million annual AR-associated deaths by 2050. The fact that infectious diseases induced by ARB are no longer treatable with antibiotics foreshadows an uncertain future in the context of health care. Hence, the One Health approach should be emphasized to reduce the impact of AR on livestock, humans, and the environment, ensuring the longevity of the efficacy of both current and prospective antibiotics.
- Published
- 2024
- Full Text
- View/download PDF
32. Complete genome sequence of Enterococcus faecium strain AK_C_05 with potential characteristics applicable in livestock industry
- Author
-
Hyunok Doo, Jin Ho Cho, Minho Song, Eun Sol Kim, Sheena Kim, Gi Beom Keum, Jinok Kwak, Sriniwas Pandey, Sumin Ryu, Yejin Choi, Juyoun Kang, Hyeun Bum Kim, and Ju-Hoon Lee
- Subjects
Enterococcus faecium ,Livestock ,Carbohydrates ,Animal culture ,SF1-1100 - Abstract
The Enterococcus faecium (E. faecium) strain AK_C_05 was isolated from cheonggukjang, the Korean traditional food, collected from a local market in South Korea. In this report, we presented the complete genome sequence of E. faecium strain AK_C_05. The genome of E. faecium strain AK_C_05 genome consisted of one circular chromosome (2,691,319 bp) with a guanine + cytosine (GC) content of 38.3% and one circular plasmid (177,732 bp) with a GC content of 35.48%. The Annotation results revealed 2,827 protein-coding sequences (CDSs), 18 rRNAs, and 68 tRNA genes. It possesses genes, which encodes enzymes such as alpha-galactosidase (EC 3.2.1.22), beta-glucosidase (EC 3.2.1.21) and alpha-L-arabinofuranosidase (EC 3.2.1.55) enabling efficient utilization of carbohydrates. Based on Clusters of Orthologous Groups analysis, E. faecium strain AK_C_05 showed specialization in carbohydrate transport and metabolism indicating the ability to generate energy using a variety of carbohydrates.
- Published
- 2024
- Full Text
- View/download PDF
33. Efficacy and Safety of COVID-19 Treatment Using Convalescent Plasma Transfusion: Updated Systematic Review and Meta-Analysis of Randomized Controlled Trials
- Author
-
Hyun-Jun Lee, Jun-Hyeong Lee, Yejin Cho, Le Thi Nhu Ngoc, and Young-Chul Lee
- Subjects
Health, Toxicology and Mutagenesis ,Immunization, Passive ,Public Health, Environmental and Occupational Health ,COVID-19 ,Humans ,COVID-19 Serotherapy ,Randomized Controlled Trials as Topic ,COVID-19 Drug Treatment - Abstract
This study investigated the efficacy and safety of convalescent plasma (CP) transfusion against the coronavirus disease 2019 (COVID-19) via a systematic review and meta-analysis of randomized controlled trials (RCTs). A total of 5467 articles obtained from electronic databases were assessed; however, only 34 RCTs were eligible after manually screening and eliminating unnecessary studies. The beneficial effect was addressed by assessing the risk ratio (RR) and standardized mean differences (SMDs) of the meta-analysis. It was demonstrated that CP therapy is not effective in improving clinical outcomes, including reducing mortality with an RR of 0.88 [0.76; 1.03] (I2 = 68% and p = 0.10) and length of hospitalization with SMD of −0.47 [−0.95; 0.00] (I2 = 99% and p = 0.05). Subgroup analysis provided strong evidence that CP transfusion does not significantly reduce all-cause mortality compared to standard of care (SOC) with an RR of 1.01 [0.99; 1.03] (I2 = 70% and p = 0.33). In addition, CP was found to be safe for and well-tolerated by COVID-19 patients as was the SOC in healthcare settings. Overall, the results suggest that CP should not be applied outside of randomized trials because of less benefit in improving clinical outcomes for COVID-19 treatment.
- Published
- 2022
34. Intrinsic expression of viperin regulates thermogenesis in adipose tissues
- Author
-
Hui-Young Lee, Seul Gi Yoon, Ki Taek Nam, Jihye Yoo, Je Kyung Seong, Hyun Ju Seo, Yejin Cho, Soojin Son, Jun-Young Seo, Ku Sul Kim, Jeong Jin Kim, Kyung Mi Choi, Haengdueng Jeong, Peter Cresswell, Il Yong Kim, John Eom, and Jae Bong Lee
- Subjects
0301 basic medicine ,Regulation of gene expression ,Multidisciplinary ,Innate immune system ,Chemistry ,Adipose tissue ,Thermogenesis ,Phenotype ,Cell biology ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,PNAS Plus ,Adipose Tissue ,Interferon ,Viperin ,Knockout mouse ,medicine ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Viperin is an interferon (IFN)-inducible multifunctional protein. Recent evidence from high-throughput analyses indicates that most IFN-inducible proteins, including viperin, are intrinsically expressed in specific tissues; however, the respective intrinsic functions are unknown. Here we show that the intrinsic expression of viperin regulates adipose tissue thermogenesis, which is known to counter metabolic disease and contribute to the febrile response to pathogen invasion. Viperin knockout mice exhibit increased heat production, resulting in a reduction of fat mass, improvement of high-fat diet (HFD)-induced glucose tolerance, and enhancement of cold tolerance. These thermogenic phenotypes are attributed to an adipocyte-autonomous mechanism that regulates fatty acid β-oxidation. Under an HFD, viperin expression is increased, and its function is enhanced. Our findings reveal the intrinsic function of viperin as a novel mechanism regulating thermogenesis in adipose tissues, suggesting that viperin represents a molecular target for thermoregulation in clinical contexts.
- Published
- 2019
35. Inactivation of Sirtuin2 protects mice from acetaminophen-induced liver injury: possible involvement of ER stress and S6K1 activation
- Author
-
Jin Hee Kim, Ki Taek Nam, Da Hyun Lee, Yong Ho Lee, Yejin Cho, Yu Seol Lee, Soo Han Bae, Jeong Su Park, Buhyun Lee, Hyun-Seok Kim, and Yoonjung Jo
- Subjects
Male ,P70-S6 Kinase 1 ,Mitochondria, Liver ,Mitochondrion ,Pharmacology ,medicine.disease_cause ,SIRT2 ,Protective Agents ,Biochemistry ,Ribosomal Protein S6 Kinases, 90-kDa ,03 medical and health sciences ,Mice ,Necrosis ,Sirtuin 2 ,medicine ,Animals ,Sirtuin2 ,Molecular Biology ,Acetaminophen ,Liver injury ,0303 health sciences ,Chemistry ,Endoplasmic reticulum ,030302 biochemistry & molecular biology ,digestive, oral, and skin physiology ,Hepatotoxicity ,General Medicine ,Articles ,S6K1 ,medicine.disease ,Endoplasmic Reticulum Stress ,Mice, Inbred C57BL ,Oxidative Stress ,Liver ,Unfolded protein response ,Hepatocytes ,Phosphorylation ,Chemical and Drug Induced Liver Injury ,ER stress ,Oxidative stress - Abstract
Acetaminophen (APAP) overdose can cause hepatotoxicity by inducing mitochondrial damage and subsequent necrosis in hepatocytes. Sirtuin2 (Sirt2) is an NAD+-dependent deacetylase that regulates several biological processes, including hepatic gluconeogenesis, as well as inflammatory pathways. We show that APAP decreases the expression of Sirt2. Moreover, the ablation of Sirt2 attenuates APAP-induced liver injuries, such as oxidative stress and mitochondrial damage in hepatocytes. We found that Sirt2 deficiency alleviates the APAP-mediated endoplasmic reticulum (ER) stress and phosphorylation of the p70 ribosomal S6 kinase 1 (S6K1). Moreover, Sirt2 interacts with and deacetylates S6K1, followed by S6K1 phosphorylation induction. This study elucidates the molecular mechanisms underlying the protective role of Sirt2 inactivation in APAP-induced liver injuries. [BMB Reports 2019; 52(3): 190-195].
- Published
- 2019
36. Structure-oriented design strategy to construct NIR AIEgens to selectively combat gram (+) multidrug-resistant bacteria in vivo
- Author
-
Haidong Li, Mengyao Yang, Ji Seon Kim, Jeongsun Ha, Jingjing Han, Heejeong Kim, Yejin Cho, Jingyun Wang, Ki Taek Nam, and Juyoung Yoon
- Subjects
Methicillin-Resistant Staphylococcus aureus ,Biomaterials ,Mice ,Photosensitizing Agents ,Mechanics of Materials ,Drug Resistance, Multiple, Bacterial ,Escherichia coli ,Biophysics ,Ceramics and Composites ,Animals ,Humans ,Bioengineering ,Anti-Bacterial Agents - Abstract
Multidrug-resistant (MDR) gram-positive bacteria are an inevitable source of infection for hospitalized patients and one of the reasons for the increased proportion of severe diseases. Therefore, constructing smart agents for specific and effective combating infections in vivo caused by MDR gram-positive strains is very urgent. Herein, we reported a structure-oriented design strategy (SODS) to reasonably construct an organic photo-antimicrobial near-infrared (NIR) AIEgen BDPTV equipped with a phenylboronic acid moiety, which could be bound to the thick peptidoglycan layer of MDR gram-positive bacteria, resulting in a tight distribution with the cell wall in a confined space. Compared to the contrast compounds DQVTA and DPTVN, upon photoirradiation of AIEgen BDPTV, the generation of abundant and highly toxic reactive oxygen species (ROS) irreversibly destroys MDR gram-positive bacteria through photodynamic therapy, which is better than commercial photosensitizers (including methylene blue, chlorin e6, and protoporphyrin IX) and antibiotic (cefoxitin). As a proof of concept, in vitro experimental results showed that methicillin-resistant Staphylococcus aureus (MRSA) were completely killed using AIEgen BDPTV. More importantly, AIEgen BDPTV was capable of successfully combating MRSA-infected wounds of mice, but not Escherichia coli (E. coli)-infected wounds. We hope that this strategy could provide a new method to design powerful AIEgens to avoid the overuse and misuse of antibiotics.
- Published
- 2022
37. Disruption of the Tff1 gene in mice using CRISPR/Cas9 promotes body weight reduction and gastric tumorigenesis
- Author
-
Yejin Cho, Ki Taek Nam, Han Woong Lee, Jae-Hoon Lee, Hye Jeong Kim, and Haengdueng Jeong
- Subjects
0301 basic medicine ,Adenoma ,Tumor suppressor gene ,Biology ,medicine.disease_cause ,03 medical and health sciences ,0302 clinical medicine ,Gastric glands ,medicine ,Gastric mucosa ,lcsh:QH301-705.5 ,CRISPR/Cas9 ,Tff1 ,lcsh:R5-920 ,gastric cancer ,Cancer ,Hyperplasia ,medicine.disease ,030104 developmental biology ,medicine.anatomical_structure ,lcsh:Biology (General) ,Tff1-knockout mouse ,Dysplasia ,030220 oncology & carcinogenesis ,Cancer research ,Original Article ,Carcinogenesis ,lcsh:Medicine (General) - Abstract
Trefoil factor 1 (TFF1, also known as pS2) is strongly expressed in the gastrointestinal mucosa and plays a critical role in the differentiation of gastric glands. Since approximately 50% of all human gastric cancers are associated with decreased TFF1 expression, it is considered a tumor suppressor gene. Tff1 deficiency in mice results in histological changes in the antral and pyloric gastric mucosa, with severe hyperplasia and dysplasia of epithelial cells, resulting in the development of antropyloric adenoma. Here, we generated Tff1-knockout (KO) mice, without a neomycin resistant (NeoR) cassette, using the clustered regularly interspaced short palindromic repeats/CRISPR-associated nuclease 9 (CRSIPR/Cas9) system. Though our Tff1-KO mice showed phenotypes very similar to the previous embryonic stem (ES)-cell-based KO mice, they differed from the previous reports in that a reduction in body weight was observed in males. These results demonstrate that these newly established Tff1-KO mice are useful tools for investigating genetic and environmental factors influencing gastric cancer, without the effects of artificial gene insertion. Furthermore, these findings suggest a novel hypothesis that Tff1 expression influences gender differences.
- Published
- 2018
38. Expression of LRIG1, a Negative Regulator of EGFR, Is Dynamically Altered during Different Stages of Gastric Carcinogenesis
- Author
-
Ki Taek Nam, Keunwook Lee, Hyunji Kim, Kyung Min Lim, Sungsook Yu, Yejin Cho, Mijeong Yang, Sang Ho Jeong, Robert J. Coffey, and James R. Goldenring
- Subjects
Male ,0301 basic medicine ,Colorectal cancer ,Mice, Nude ,Apoptosis ,Nerve Tissue Proteins ,Biology ,Article ,Pathology and Forensic Medicine ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Stomach Neoplasms ,Metaplasia ,Tumor Cells, Cultured ,medicine ,Animals ,Humans ,Epidermal growth factor receptor ,Cell Proliferation ,Neoplasm Staging ,Regulation of gene expression ,Gene knockdown ,Membrane Glycoproteins ,Cell growth ,Stomach ,Cancer ,Intestinal metaplasia ,medicine.disease ,Xenograft Model Antitumor Assays ,ErbB Receptors ,Gene Expression Regulation, Neoplastic ,Survival Rate ,030104 developmental biology ,Case-Control Studies ,030220 oncology & carcinogenesis ,Cancer research ,biology.protein ,medicine.symptom - Abstract
Leucine-rich repeats and immunoglobulin-like domains (LRIG)-1 is a transmembrane protein that antagonizes epidermal growth factor receptor signaling in epithelial tissues. LRIG1 is down-regulated in various epithelial cancers, including bladder, breast, and colorectal cancer, suggesting that it functions as a tumor suppressor. However, its role in gastric carcinogenesis is not well understood. Here, we investigated the changes in LRIG1 expression during the stages of gastric cancer. We used a DMP-777–induced spasmolytic polypeptide-expressing metaplasia mouse model and a tissue array of human gastric cancer lesions. The effects of LRIG1 knockdown were also assessed using the human gastric cancer cell line SNU638 in a xenograft model. LRIG1 expression varied over the course of gastric carcinogenesis, increasing in spasmolytic polypeptide-expressing metaplasia lesions but disappearing in intestinal metaplasia and cancer lesions, and the increase was concurrent with the up-regulation of epidermal growth factor receptor. In addition, LRIG1 knockdown promoted the tumorigenic potential in vitro, which was manifested as increased proliferation, invasiveness, and migration as well as increased tumor size in vivo in the xenograft model. Furthermore, LRIG1 expression was determined to be a positive prognostic biomarker for the survival of gastric cancer patients. Collectively, our findings indicate that LRIG1 expression is closely related wto gastric carcinogenesis and may play a vital role as a tumor suppressor through the modulation of epidermal growth factor receptor activity.
- Published
- 2018
39. Evaluation of the skin phototoxicity of systemically administered pharmaceuticals in Sprague–Dawley rats
- Author
-
Jong Kwon Lee, Ki Sook Park, Eun Ji Kim, Nam Hee Youn, Ki Taek Nam, Jung-Sun Yi, Yejin Cho, and Joo Hwan Kim
- Subjects
Drug ,business.industry ,Health, Toxicology and Mutagenesis ,media_common.quotation_subject ,Radiation dose ,Ultraviolet a ,010501 environmental sciences ,Pharmacology ,Toxicology ,030226 pharmacology & pharmacy ,01 natural sciences ,Phototoxicity Study ,03 medical and health sciences ,0302 clinical medicine ,In vivo ,Sprague dawley rats ,Medicine ,Original Article ,Phototoxicity ,business ,0105 earth and related environmental sciences ,media_common ,Skin Findings - Abstract
In vivo phototoxicity testing is important for predicting drug-induced phototoxicity in humans. Currently, there is no internationally validated in vivo test method for the photosafety evaluation of pharmaceuticals. In this study, we evaluated the phototoxicity of systemically administered drugs using SD rats. We first determined the appropriate ultraviolet A (UVA) dose using 8-methoxypsoralen, a well-known phototoxic drug. Compared to lower and higher UVA doses, we found that a UVA dose of 10 J/cm(2) allowed for the detection of phototoxic responses in both a dose- and time-dependent manner. We next performed a phototoxicity study using seven pharmaceutical drugs which included known phototoxic and non-phototoxic drugs using a UVA dose of 10 J/cm(2). In order to improve the accuracy of our assessment, we evaluated both gross skin findings as well as histopathological findings. Using gross skin findings alone resulted in an accuracy of 85.7% which could be increased to 100% accuracy when the gross skin findings were combined with histopathological findings. This study suggests that the inclusion of histopathological findings increases the accuracy of the phototoxicity evaluation of systemically administered drugs in SD rats. In conclusion, we found that for studying drug-induced phytotoxicity, a 10 J/cm(2) UVA dose serves as the optimal radiation dose, and that the inclusion of histopathological findings increases the accuracy of the phototoxicity evaluation of the drugs.
- Published
- 2021
40. Identification of gaze pattern and blind spots by upper gastrointestinal endoscopy using an eye-tracking technique
- Author
-
Ayoung, Lee, Hyunsoo, Chung, Yejin, Cho, Jue Lie, Kim, Jinju, Choi, Eunwoo, Lee, Bokyung, Kim, Soo-Jeong, Cho, and Sang Gyun, Kim
- Subjects
Upper Gastrointestinal Tract ,Humans ,Fixation, Ocular ,Eye-Tracking Technology ,Endoscopy, Gastrointestinal - Abstract
The lesion detection rate of esophagogastroduodenoscopy (EGD) varies depending on the degree of experience of the endoscopist and anatomical blind spots. This study aimed to identify gaze patterns and blind spots by analyzing the endoscopist's gaze during real-time EGD.Five endoscopists were enrolled in this study. The endoscopist's eye gaze tracked by an eye tracker was selected from the esophagogastric junction to the second portion of the duodenum without the esophagus during insertion and withdrawal, and then matched with photos. Gaze patterns were visualized as a gaze plot, blind spot detection as a heatmap, observation time (OT), fixation duration (FD), and FD-to-OT ratio.The mean OT and FD were 11.10 ± 11.14 min and 8.37 ± 9.95 min, respectively, and the FD-to-OT ratio was 72.5%. A total of 34.3% of the time was spent observing the antrum. When observing the body of the stomach, it took longer to observe the high body in the retroflexion view and the low-to-mid body in the forward view.It is necessary to minimize gaze distraction and observe the posterior wall in the retroflexion view. Our results suggest that eye-tracking techniques may be useful for future endoscopic training and education.
- Published
- 2021
41. Human gastric microbiota transplantation recapitulates premalignant lesions in germ-free mice.
- Author
-
Soon-Kyeong Kwon, Jun Chul Park, Kim, Kwang H., Jaekyung Yoon, Yejin Cho, Buhyun Lee, Jin-Jae Lee, Haengdueng Jeong, Yeseul Oh, Sung-Hee Kim, So Dam Lee, Bo Ram Hwang, Yusook Chung, Kim, Jihyun F., Ki Taek Nam, and Yong Chan Lee
- Subjects
HELICOBACTER pylori infections ,HUMAN microbiota ,PRECANCEROUS conditions ,BACTERIAL colonies ,MICE ,MEDICAL sciences ,FLAVOBACTERIALES ,STREPTOCOCCUS - Published
- 2022
- Full Text
- View/download PDF
42. Evaluation of skin phototoxicity of transdermally administered pharmaceuticals in Sprague-Dawley rats
- Author
-
Nam Hee Youn, Eun Ji Kim, Ki Sook Park, Jung-Sun Yi, Joo Hwan Kim, Jong Kwon Lee, Ki Taek Nam, and Yejin Cho
- Subjects
Drug ,Erythema ,media_common.quotation_subject ,Histopathology ,Pharmacology ,Skin reaction ,030226 pharmacology & pharmacy ,Phototoxicity ,03 medical and health sciences ,0302 clinical medicine ,In vivo ,medicine ,Sprague dawley rats ,lcsh:QH301-705.5 ,media_common ,Transdermal ,lcsh:R5-920 ,In vivo test ,business.industry ,Research ,Phototoxicity Study ,Skin irritation ,lcsh:Biology (General) ,030220 oncology & carcinogenesis ,medicine.symptom ,lcsh:Medicine (General) ,business - Abstract
Some drugs cause phototoxicity in humans when exposed to light, thus there is a need for an in vivo phototoxicity test to evaluate them. However, an in vivo phototoxicity test method to evaluate this has not been established. This study aimed to establish an in vivo phototoxicity test method for transdermally administered drugs. For this, we evaluated the phototoxicity using Sprague-Dawley (SD) rats for transdermal administered drugs and we studied the appropriate UVA dose using 8-methoxypsalen, which is a well-known phototoxic drug. We found that a UVA dose of 15 J/cm2 was dose and time dependent response compared to other UVA doses. We performed the Minimum Erythema Dose (MED) test because UVB can cause skin irritation by itself and selected 0.01 J/cm2 as an appropriate dose of UVB. Using the selected UVA and UVB doses, we performed a phototoxicity study of 6 pharmaceutical drugs, which included phototoxic and non-phototoxic drugs. As a result of the phototoxicity test, 100% accuracy was obtained when compared with previous studies. In addition, we performed histopathology to confirm the new findings. We found that histopathology can be used as an additional indicator of phototoxicity test for transdermally administered drugs.
- Published
- 2020
43. Leveraging WordNet Paths for Neural Hypernym Prediction
- Author
-
Yifan Gao, Yejin Cho, Katrin Erk, and Juan Diego Rodriguez
- Subjects
Sequence ,Computer science ,business.industry ,WordNet ,02 engineering and technology ,010501 environmental sciences ,Machine learning ,computer.software_genre ,01 natural sciences ,Task (project management) ,Taxonomy (general) ,0202 electrical engineering, electronic engineering, information engineering ,Benchmark (computing) ,020201 artificial intelligence & image processing ,Artificial intelligence ,business ,computer ,0105 earth and related environmental sciences - Abstract
We formulate the problem of hypernym prediction as a sequence generation task, where the sequences are taxonomy paths in WordNet. Our experiments with encoder-decoder models show that training to generate taxonomy paths can improve the performance of direct hypernym prediction. As a simple but powerful model, the hypo2path model achieves state-of-the-art performance, outperforming the best benchmark by 4.11 points in hit-at-one (H@1).
- Published
- 2020
44. Biallelic Deletion of Pxdn in Mice Leads to Anophthalmia and Severe Eye Malformation
- Author
-
Kyung A. Ham, Hyun Kyung Kim, Hae-Sol Shin, Hong Kyung Kim, Hong Sug Kim, Kyoung Yul Seo, Hong Seok Choi, Young Ae Joe, Yejin Cho, In-Beom Kim, Seung Woo Lee, and Ki Taek Nam
- Subjects
0301 basic medicine ,genetic structures ,030105 genetics & heredity ,Biology ,anophthalmia ,Microphthalmia ,Catalysis ,Inorganic Chemistry ,03 medical and health sciences ,Exon ,Dysgenesis ,medicine ,Physical and Theoretical Chemistry ,Molecular Biology ,CRISPR/Cas9 ,Spectroscopy ,Gene knockout ,Anophthalmia ,Organic Chemistry ,General Medicine ,medicine.disease ,Molecular biology ,eye diseases ,peroxidasin ,Computer Science Applications ,030104 developmental biology ,microphthalmia ,Knockout mouse ,eye development ,Eye development ,Eye disorder ,sense organs ,knockout mice - Abstract
Peroxidasin (PXDN) is a unique peroxidase containing extracellular matrix motifs and stabilizes collagen IV networks by forming sulfilimine crosslinks. PXDN gene knockout in Caenorhabditis elegans (C. elegans) and Drosophila results in the demise at the embryonic and larval stages. PXDN mutations lead to severe eye disorders, including microphthalmia, cataract, glaucoma, and anterior segment dysgenesis in humans and mice. To investigate how PXDN loss of function affects organ development, we generated Pxdn knockout mice by deletion of exon 1 and its 5&prime, upstream sequences of the Pxdn gene using the CRISPR/Cas9 system. Loss of both PXDN expression and collagen IV sulfilimine cross-links was detected only in the homozygous mice, which showed completely or almost closed eyelids with small eyes, having no apparent external morphological defects in other organs. In histological analysis of eye tissues, the homozygous mice had extreme defects in eye development, including no eyeballs or drastically disorganized eye structures, whereas the heterozygous mice showed normal eye structure. Visual function tests also revealed no obvious functional abnormalities in the eyes between heterozygous mice and wild-type mice. Thus, these results suggest that PXDN activity is essential in eye development, and also indicate that a single allele of Pxdn gene is sufficient for eye-structure formation and normal visual function.
- Published
- 2019
- Full Text
- View/download PDF
45. The development of baked kelp snack through examining its physicochemical properties
- Author
-
박선민 ( Sunmin Park ), 홍정의 ( Jeonguie Hong ), 오지희 ( Jihee Oh ), 조예진 ( Yejin Cho ), and 강선아 ( Suna Kang )
- Subjects
0301 basic medicine ,03 medical and health sciences ,030109 nutrition & dietetics ,Chemistry ,Organic Chemistry ,Bioengineering ,Food science - Abstract
미역이나 다시마와 같은 해조류는 생물의 상태로 유통될 수 없는 어려움이 있어 건조, 염장, 당장 등의 가공 처리가 필요하다. 본 실험에서는 다시마를 건조 및 전처리를 하여 해조류에 거부감을 가지고 있는 내륙지역에서도 쉽게 접근할 수 있는 스낵으로 제조하고, 맛과 씹힘성이 좋으며 비린 맛이 없어 누구나 좋아하는 스낵을 개발하고, 개발한 스낵의 물리화학적 특성을 연구하였다. 다시마 연화에 탁월한 폴리인산나트륨 용액 농도 탐색 실험에서는 0.2-0.3% 농도의 폴리인산나트륨 용액에 침지시키는 것이 다시마 연화나 맛에서 좋았고 부드러운 질감을 나타내었다. 폴리인산나트륨 용액 침지 및 굽는 처리를 달리한 다시마 스낵 제조에서는 두께가 221 mm 미만인 것은 얇은 것으로, 221 mm 이상인 것은 두꺼운 것으로 분류하여 실험을 진행하였는데, 두꺼운 다시마 스낵에서 모든 실험 결과에서 일관된 결과를 보이는 반면 얇은 다시마의 경우 일관된 결과를 보이지 않아 두꺼운 다시마로 스낵을 제조하는 것이 바람직해 보였다. 다시마 스낵은 굽는 처리를 한 것이 수분함량과 조회분 함량에서 유의적으로 높은 값을 나타내었으며, 폴리인산나트륨 용액에 침지시킨 것이 낮은 경도 값을 나타내는 것으로 보아 폴리인산나트륨 용액에 침지로 인해 다시마가 부드러워지는 것을 확인할 수 있었다. 전자현미경 촬영 결과 폴리인산나트륨 용액에 침지시키고 굽는 처리를 한 다시마 스낵이 조직이 부드러워지는 것과 좋은 질감을 가지는 것을 확인할 수 있었다. 다시마로 스낵을 제조할 때는 단백질과 회분 함량이 적절하게 포함된 중층부 다시마의 두꺼운 부분을 사용하는 것이 좋으며, 음지에서 건조시킨 다시마를 사용하는 것이 저장성이 높은 다시마 스낵을 제조하는데 바람직할 것으로 보인다. 가공 처리의 경우 폴리인산나트륨 용액에 침지 및 굽는 처리를 하여 단맛이나 매운맛의 조미를 가하여 다시마 스낵을 제조할 경우 이 물감이 없고 씹힘성이 좋으며 비린 맛이 없는 상품성이 높은 다시마 스낵을 제조할 수 있을 것으로 보인다. 해조류 섭취의 중요성에 대한 연구들이 뒷받침된다면 다시마 스낵이 남미에 수출되면 갑상선종에 대한 예방이 가능하고 수출 증대로 국가적 이익을 창출 할 수 있을 것으로 기대된다.
- Published
- 2018
46. WFDC2 Promotes Spasmolytic Polypeptide-Expressing Metaplasia Through the Up-Regulation of IL33 in Response to Injury
- Author
-
Buhyun Lee, Ki Taek Nam, James R. Goldenring, Jong-Hwan Park, Ah-Ra Jang, Ji-Ho Park, Bo Ram Hwang, Soo Young Cho, Kwang H. Kim, Yejin Cho, Yong Chan Lee, Sang-Ho Jeong, Kyung Min Lim, Yura Lee, Jeongeun Park, Yeseul Oh, Haengdueng Jeong, and Daekee Lee
- Subjects
Biology ,Bone marrow-derived macrophage ,medicine.disease_cause ,Article ,Transcriptome ,WAP Four-Disulfide Core Domain Protein 2 ,Downregulation and upregulation ,WFDC2 ,Stomach Neoplasms ,Fibrosis ,Metaplasia ,medicine ,Animals ,Mice, Knockout ,Hepatology ,Gene Expression Profiling ,Macrophages ,Gastroenterology ,Intestinal metaplasia ,Interleukin-33 ,medicine.disease ,Up-Regulation ,Mice, Inbred C57BL ,Disease Models, Animal ,Cell Transformation, Neoplastic ,Phenotype ,Gastric Mucosa ,Cancer research ,Intercellular Signaling Peptides and Proteins ,Atrophy ,medicine.symptom ,Carcinogenesis ,Precancerous Conditions - Abstract
Background & Aims WAP 4-disulfide core domain protein 2 (WFDC2), also known as human epididymis protein 4, is a small secretory protein that is highly expressed in fibrosis and human cancers, particularly in the ovaries, lungs, and stomach. However, the role of WFDC2 in carcinogenesis is not fully understood. The present study aimed to investigate the role of WFDC2 in gastric carcinogenesis with the use of preneoplastic metaplasia models. Methods Three spasmolytic polypeptide–expressing metaplasia (SPEM) models were established in both wild-type and Wfdc2-knockout mice with DMP-777, L635, and high-dose tamoxifen, respectively. To reveal the functional role of WFDC2, we performed transcriptomic analysis with DMP-777–treated gastric corpus specimens. Results Wfdc2-knockout mice exhibited remarkable resistance against oxyntic atrophy, SPEM emergence, and accumulation of M2-type macrophages in all 3 SPEM models. Transcriptomic analysis revealed that Wfdc2-knockout prevented the up-regulation of interleukin-33 (IL33) expression in the injured mucosal region of SPEM models. Notably, supplementation of recombinant WFDC2 induced IL33 production and M2 macrophage polarization, and ultimately promoted SPEM development. Moreover, long-term treatment with recombinant WFDC2 was able to induce SPEM development. Conclusions WFDC2 expressed in response to gastric injury promotes SPEM through the up-regulation of IL33 expression. These findings provide novel insights into the role of WFDC2 in gastric carcinogenesis.
- Published
- 2021
47. Expression Levels of GABA-A Receptor Subunit Alpha 3,Gabra3and Lipoprotein Lipase,LplAre Associated with the Susceptibility to Acetaminophen-Induced Hepatotoxicity
- Author
-
Ki Taek Nam, Yejin Cho, Jun Won Yun, Mijeong Yang, Kyeho Shin, Kyung Min Lim, and Minjeong Kim
- Subjects
0301 basic medicine ,Pharmacology ,Liver injury ,Lipoprotein lipase ,biology ,Microarray ,Microarray analysis techniques ,digestive, oral, and skin physiology ,medicine.disease ,Biochemistry ,Acetaminophen ,03 medical and health sciences ,030104 developmental biology ,Drug Discovery ,Gene expression ,medicine ,biology.protein ,Molecular Medicine ,GABRA3 ,Toxicogenomics ,medicine.drug - Abstract
Drug-induced liver injury (DILI) is the serious and fatal drug-associated adverse effect, but its incidence is very low and individual variation in severity is substantial. Acetaminophen (APAP)-induced liver injury accounts for >50% of reported DILI cases but little is known for the cause of individual variations in the severity. Intrinsic genetic variation is considered a key element but the identity of the genes was not well-established. Here, pre-biopsy method and microarray technique was applied to uncover the key genes for APAP-induced liver injury in mice, and a cause and effect experiment employing quantitative real-time PCR was conducted to confirm the correlation between the uncovered genes and APAP-induced hepatotoxicity. We identified the innately and differentially expressed genes of mice susceptible to APAP-induced hepatotoxicity in the pre-biopsied liver tissue before APAP treatment through microarray analysis of the global gene expression profiles (Affymetrix GeneChip® Mouse Gene 1.0 ST for 28,853 genes). Expression of 16 genes including Gdap10, Lpl, Gabra3 and Ccrn4l were significantly different (t-test: FDR
- Published
- 2017
48. Biallelic Deletion of
- Author
-
Hyun-Kyung, Kim, Kyung A, Ham, Seung-Woo, Lee, Hong Seok, Choi, Hong-Sug, Kim, Hong Kyung, Kim, Hae-Sol, Shin, Kyoung Yul, Seo, Yejin, Cho, Ki Taek, Nam, In-Beom, Kim, and Young Ae, Joe
- Subjects
Collagen Type IV ,Mice, Knockout ,genetic structures ,Anophthalmos ,anophthalmia ,Eye ,eye diseases ,Article ,peroxidasin ,Mice ,Peroxidases ,microphthalmia ,eye development ,Animals ,sense organs ,CRISPR-Cas Systems ,CRISPR/Cas9 ,Gene Deletion ,Vision, Ocular ,knockout mice - Abstract
Peroxidasin (PXDN) is a unique peroxidase containing extracellular matrix motifs and stabilizes collagen IV networks by forming sulfilimine crosslinks. PXDN gene knockout in Caenorhabditis elegans (C. elegans) and Drosophila results in the demise at the embryonic and larval stages. PXDN mutations lead to severe eye disorders, including microphthalmia, cataract, glaucoma, and anterior segment dysgenesis in humans and mice. To investigate how PXDN loss of function affects organ development, we generated Pxdn knockout mice by deletion of exon 1 and its 5′ upstream sequences of the Pxdn gene using the CRISPR/Cas9 system. Loss of both PXDN expression and collagen IV sulfilimine cross-links was detected only in the homozygous mice, which showed completely or almost closed eyelids with small eyes, having no apparent external morphological defects in other organs. In histological analysis of eye tissues, the homozygous mice had extreme defects in eye development, including no eyeballs or drastically disorganized eye structures, whereas the heterozygous mice showed normal eye structure. Visual function tests also revealed no obvious functional abnormalities in the eyes between heterozygous mice and wild-type mice. Thus, these results suggest that PXDN activity is essential in eye development, and also indicate that a single allele of Pxdn gene is sufficient for eye-structure formation and normal visual function.
- Published
- 2019
49. Sexually dimorphic leanness and hypermobility in p16Ink4a/CDKN2A-deficient mice coincides with phenotypic changes in the cerebellum
- Author
-
Soo In Kim, Chang Hoon Kim, Yura Lee, Jae-Hoon Lee, Kwang H. Kim, Han Woong Lee, Ki Taek Nam, Yejin Cho, and Haengdueng Jeong
- Subjects
0301 basic medicine ,Senescence ,medicine.medical_specialty ,Cerebellum ,medicine.drug_class ,Science ,Estrogen receptor ,Adipose tissue ,White adipose tissue ,Biology ,Deep cerebellar nuclei ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,neoplasms ,Multidisciplinary ,030104 developmental biology ,medicine.anatomical_structure ,Endocrinology ,Estrogen ,Medicine ,030217 neurology & neurosurgery ,Homeostasis - Abstract
p16Ink4a/CDKN2A is a tumor suppressor that critically regulates the cell cycle. Indeed, p16Ink4a deficiency promotes tumor formation in various tissues. We now report that p16Ink4a deficiency in female mice, but not male mice, induces leanness especially in old age, as indicated by lower body weight and smaller white adipose tissue, although other major organs are unaffected. Unexpectedly, the integrity, number, and sizes of adipocytes in white adipose tissue were unaffected, as was macrophage infiltration. Hence, hypermobility appeared to be accountable for the phenotype, since food consumption was not altered. Histological analysis of the cerebellum and deep cerebellar nuclei, a vital sensorimotor control center, revealed increased proliferation of neuronal cells and improved cerebellum integrity. Expression of estrogen receptor β (ERβ) and PCNA also increased in deep cerebellar nuclei, implying crosstalk between p16Ink4a and ERβ. Furthermore, p16Ink4a deficiency expands LC3B+ cells and GFAP+ astrocytes in response to estrogen. Collectively, the data suggest that loss of p16INK4a induces sexually dimorphic leanness in female mice, which appears to be due to protection against cerebellar senescence by promoting neuronal proliferation and homeostasis via ERβ.
- Published
- 2019
50. Loss of Rab25 promotes the development of skin squamous cell carcinoma through the dysregulation of integrin trafficking
- Author
-
Buhyun Lee, Ki Taek Nam, Joseph T. Roland, Byron C. Knowles, Haengdueng Jeong, Kwang H. Kim, Kyung Min Lim, Yejin Cho, Jeffrey P. Zwerner, and James R. Goldenring
- Subjects
0301 basic medicine ,Keratinocytes ,Integrins ,Mice, 129 Strain ,Skin Neoplasms ,Integrin ,Down-Regulation ,medicine.disease_cause ,Article ,Pathology and Forensic Medicine ,Malignant transformation ,03 medical and health sciences ,0302 clinical medicine ,Cell Line, Tumor ,Skin Squamous Cell Carcinoma ,medicine ,Animals ,Humans ,Neoplastic transformation ,Cell Proliferation ,Mice, Knockout ,biology ,Cell growth ,Tumor Suppressor Proteins ,Proteins ,Tumor Burden ,Gene Expression Regulation, Neoplastic ,HaCaT ,Protein Transport ,030104 developmental biology ,Cell culture ,rab GTP-Binding Proteins ,030220 oncology & carcinogenesis ,biology.protein ,Cancer research ,Carcinoma, Squamous Cell ,Carcinogenesis ,Signal Transduction - Abstract
Rab25 can function as both a tumor suppressor and a tumor promoter across different tissues. This study sought to clarify the role of Rab25 as a tumor suppressor in skin squamous cell carcinoma (SCC). Rab25 loss was closely associated with neoplastic transition in both humans and mice. Rab25 loss was well correlated with increased cell proliferation and poor differentiation in human SCC. While Rab25 knockout (KO) in mice did not induce spontaneous tumor formation, it did significantly accelerate tumor generation and promote malignant transformation in a mouse two-stage skin carcinogenesis model. Xenografting of a Rab25-deficient human keratinocyte cell line, HaCaT, also elicited neoplastic transformation. Notably, Rab25 deficiency led to dysregulation of integrins β1, β4, and α6, which matched well with increased epidermal proliferation and impaired desmosome-tight junction formation. Rab25 deficiency induced impairment of integrin recycling, leading to the improper expression of integrins. In line with this, significant attenuation of integrin β1, β4, and α6 expression was identified in human SCCs where Rab25 was deficient. Collectively, these results suggest that loss of Rab25 promotes the development and neoplastic transition of SCC through dysregulation of integrin trafficking. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
- Published
- 2019
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.