• Clinical and Experimental Reproductive Medicine
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• v.51 no.1
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• pp.20-27
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• 2024

Objective: While sperm freezing (cryopreservation) is an effective method for preserving fertility, it can potentially harm the structure and function of sperm due to an increase in the production of reactive oxygen species. This study aimed to assess the impact of zinc oxide nanoparticles (ZnONPs) and selenium oxide nanoparticles (SeONPs) on various sperm functional parameters, including motility, plasma membrane integrity (PMI), mitochondrial membrane potential (MMP), acrosome membrane integrity (ACi), and malondialdehyde (MDA) levels. Methods: Semen samples were collected from 20 Albino Wistar rats. These samples were then divided into six groups: fresh, cryopreservation control, and groups supplemented with SeONPs (1, 2, 5 ㎍/mL) and ZnONPs (0.1, 1, 10 ㎍/mL). Results: Statistical analysis revealed that all concentrations of SeONPs increased total motility and progressive reduction of MDA levels compared to the cryopreservation control group (p<0.05). However, supplementation with ZnONPs did not affect these parameters (p>0.05). Conversely, supplements of 1 and 2 ㎍/mL SeONPs and 1 ㎍/mL ZnONPs contributed to the improvement of PMI and ACi (p<0.05). Yet, no significant change was observed in MMP with any concentration of SeONPs and ZnONPs compared to the cryopreservation control group (p>0.05). Conclusion: The findings suggest that optimal concentrations of SeONPs may enhance sperm parameters during the freezing process.

• Korean Circulation Journal
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• v.53 no.8
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• pp.499-518
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• 2023

Cardiovascular diseases (CVDs), including coronary artery disease, stroke, heart failure, and hypertension, are the global leading causes of death, accounting for more than 30% of deaths worldwide. Although the risk factors of CVDs have been well understood and various treatment and preventive measures have been established, the mortality rate and the financial burden of CVDs are expected to grow exponentially over time due to the changes in lifestyles and increasing life expectancies of the present generation. Recent advancements in metagenomics and metabolomics analysis have identified gut microbiome and its associated metabolites as potential risk factors for CVDs, suggesting the possibility of developing more effective novel therapeutic strategies against CVD. In addition, increasing evidence has demonstrated the alterations in the ratio of Firmicutes to Bacteroidetes and the imbalance of microbial-dependent metabolites, including short-chain fatty acids and trimethylamine N-oxide, play a crucial role in the pathogenesis of CVD. However, the exact mechanism of action remains undefined to this day. In this review, we focus on the compositional changes in the gut microbiome and its related metabolites in various CVDs. Moreover, the potential treatment and preventive strategies targeting the gut microbiome and its metabolites are discussed.

• Korean Circulation Journal
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• v.53 no.1
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• pp.17-30
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• 2023

Background and Objectives: To evaluate the impact of smoking in young adults on the risk of cardiovascular disease (CVD) and the clustering effect of behavioral risk factors such as smoking, obesity, and depression. Methods: A Korean nationwide population-based cohort of a total of 3,280,826 participants aged 20-39 years old who underwent 2 consecutive health examinations were included. They were followed up until the date of CVD (myocardial infarction [MI] or stroke), or December 2018 (median, 6 years). Results: Current smoking, early age of smoking initiation, and smoking intensity were associated with an increased risk of CVD incidence. Even after quitting smoking, the risk of MI was still high in quitters compared with non-smokers. Cigarette smoking, obesity, and depression were independently associated with a 1.3-1.7 times increased risk of CVD, and clustering of 2 or more of these behavioral risk factors was associated with a 2-3 times increased risk of CVD in young adults. Conclusions: In young adults, cigarette smoking was associated with the risk of CVD, and the clustering of 2 or more behavioral risk factors showed an additive risk of CVD.

• Korean Journal of Radiology
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• v.25 no.3
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• pp.224-242
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• 2024

The emergence of Chat Generative Pre-trained Transformer (ChatGPT), a chatbot developed by OpenAI, has garnered interest in the application of generative artificial intelligence (AI) models in the medical field. This review summarizes different generative AI models and their potential applications in the field of medicine and explores the evolving landscape of Generative Adversarial Networks and diffusion models since the introduction of generative AI models. These models have made valuable contributions to the field of radiology. Furthermore, this review also explores the significance of synthetic data in addressing privacy concerns and augmenting data diversity and quality within the medical domain, in addition to emphasizing the role of inversion in the investigation of generative models and outlining an approach to replicate this process. We provide an overview of Large Language Models, such as GPTs and bidirectional encoder representations (BERTs), that focus on prominent representatives and discuss recent initiatives involving language-vision models in radiology, including innovative large language and vision assistant for biomedicine (LLaVa-Med), to illustrate their practical application. This comprehensive review offers insights into the wide-ranging applications of generative AI models in clinical research and emphasizes their transformative potential.

• International Journal of Stem Cells
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• v.16 no.1
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• pp.36-43
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• 2023

Background and Objectives: Lymphoblastoid cell lines (LCLs) deposited from disease-affected individuals could be a valuable donor cell source for generating disease-specific induced pluripotent stem cells (iPSCs). However, generation of iPSCs from the LCLs is still challenging, as yet no effective gene delivery strategy has been developed. Methods and Results: Here, we reveal an effective gene delivery method specifically for LCLs. We found that LCLs appear to be refractory toward retroviral and lentiviral transduction. Consequently, lentiviral and retroviral transduction of OCT4, SOX2, KFL4 and c-MYC into LCLs does not elicit iPSC colony formation. Interestingly, however we found that transfection of oriP/EBNA-1-based episomal vectors by electroporation is an efficient gene delivery system into LCLs, enabling iPSC generation from LCLs. These iPSCs expressed pluripotency makers (OCT4, NANOG, SSEA4, SALL4) and could form embryoid bodies. Conclusions: Our data show that electroporation is an effective gene delivery method with which LCLs can be efficiently reprogrammed into iPSCs.

• International Journal of Stem Cells
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• v.16 no.1
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• pp.44-51
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• 2023

Background and Objectives: DNA methyltransferases (Dnmts) play an important role in regulating DNA methylation during early developmental processes and cellular differentiation. In this study, we aimed to investigate the role of Dnmts in neural differentiation of embryonic stem cells (ESCs) and in maintenance of the resulting neural stem cells (NSCs). Methods and Results: We used three types of Dnmt knockout (KO) ESCs, including Dnmt1 KO, Dnmt3a/3b double KO (Dnmt3 DKO), and Dnmt1/3a/3b triple KO (Dnmt TKO), to investigate the role of Dnmts in neural differentiation of ESCs. All three types of Dnmt KO ESCs could form neural rosette and differentiate into NSCs in vitro. Interestingly, however, after passage three, Dnmt KO ESC-derived NSCs could not maintain their self-renewal and differentiated into neurons and glial cells. Conclusions: Taken together, the data suggested that, although deficiency of Dnmts had no effect on the differentiation of ESCs into NSCs, the latter had defective maintenance, thereby indicating that Dnmts are crucial for self-renewal of NSCs.

• Journal of Plant Biotechnology
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• v.50
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• pp.89-95
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• 2023

In order to investigate the effect of carbon sources on somatic embryogenesis and cotyledon number variations in carrot, embryogenic callus were cultured in the medium supplemented with various concentrations of sucroseor glucose, and with combination of 2% sucrose and various concentrations of mannitol or sorbitol. The maximum number of somatic embryos formed per flask (1,555.70) was obtained in the medium supplemented with 2% sucrose rather than glucose alone or a combination of mannitol or sorbitol and 2% sucrose, and the number of somatic embryos was decreased with the increasing of mannitol or sorbitol concentration. The frequencies of somatic embryos with two cotyledons were 35.14% for sucrose, 19.88% for glucose, 32.55% for mannitol + 2% sucrose, and 38.59% for sorbitol + 2% sucrose, respectively, and the frequencies of abnormal somatic embryos having 3 or more cotyledons were 64.86% for sucrose, 80.12% for glucose, 67.44% for mannitol + 2% sucrose, and 61.41% for sorbitol + 2% sucrose, respectively. Particularly, the frequency of somatic embryos with two cotyledons (59.16%) was the highest in the 2% sucrose medium compared to the frequency of abnormal somatic embryogenesis with three or more cotyledons, and the frequency gradually decreased with increasing concentration of glucose, mannitol or sorbitol. According to these results, it was found that the ratio of abnormal somatic embryo was higher than the normal somatic embryo in carrot, and was shown that somatic embryogenesis and the cotyledon number was affected by the concentrations of sucrose, glucose as carbon source, and mannitol and sorbitol as osmotic agents in culture medium.

• Biomolecules & Therapeutics
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• v.32 no.3
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• pp.341-348
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• 2024

Endoplasmic reticulum (ER) stress plays a crucial role in liver diseases, affecting various types of hepatic cells. While studies have focused on the link between ER stress and hepatocytes as well as hepatic stellate cells (HSCs), the precise involvement of hepatic macrophages in ER stress-induced liver injury remains poorly understood. Here, we examined the effects of ER stress on hepatic macrophages and their role in liver injury. Acute ER stress led to the accumulation and activation of hepatic macrophages, which preceded hepatocyte apoptosis. Notably, macrophage depletion mitigated liver injury induced by ER stress, underscoring their detrimental role. Mechanistic studies revealed that ER stress stimulates macrophages predominantly via the PERK signaling pathway, regardless of its canonical substrate ATF4. hnRNPA1 has been identified as a crucial mediator of PERK-driven macrophage activation, as the overexpression of hnRNPA1 effectively reduced ER stress and suppressed pro-inflammatory activation. We observed that hnRNPA1 interacts with mRNAs that encode UPR-related proteins, indicating its role in the regulation of ER stress response in macrophages. These findings illuminate the cell type-specific responses to ER stress and the significance of hepatic macrophages in ER stress-induced liver injury. Collectively, the PERK-hnRNPA1 axis has been discovered as a molecular mechanism for macrophage activation, presenting prospective therapeutic targets for inflammatory hepatic diseases such as acute liver injury.

• Journal of Animal Science and Technology
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• v.66 no.1
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• pp.204-218
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• 2024

Elsholtzia fruticosa (EF) is present in tropical regions throughout South Asian countries as well as the Himalayas. Although it has been used as a traditional medicine to treat digestive, respiratory, and inflammatory issues, its effect on preadipocyte differentiation is unknown. In this study, we examined the effects of a methanol extract prepared from EF on the differentiation of 3T3-L1 preadipocytes. Cell differentiation was assessed by microscopic observation and oil-red O staining. The expression of adipogenic and lipogenic genes, including PPARγ and C/EBPα, was measured by western blot analysis and quantitative real-time polymerase chain reaction (qRT-PCR), to provide insight into adipogenesis and lipogenesis mechanisms. The results indicated that EF promotes the differentiation of 3T3-L1 preadipocytes, with elevated lipid accumulation occurring in a concentration-dependent manner without apparent cytotoxicity. EF enhances the expression of adipogenic and lipogenic genes, including PPARγ, FABP4, adiponectin, and FAS, at the mRNA and protein levels. The effect of EF was more pronounced during the early and middle stages of 3T3-L1 cell differentiation. Treatment with EF decreased C/EBP homologous protein (CHOP) mRNA and protein levels, while increasing C/EBPα and PPARγ expression. Treatment with EF resulted in the upregulation of cyclin E and CDK2 gene expression within 24 h, followed by a decrease at 48 h, demonstrating the early-stage impact of EF. A concomitant increase in cyclin-D1 levels was observed compared with untreated cells, indicating that EF modulates lipogenic and adipogenic genes through intricate mechanisms involving CHOP and cell cycle pathways. In summary, EF induces the differentiation of 3T3-L1 preadipocytes by increasing the expression of adipogenic and lipogenic genes, possibly through CHOP and cell cycle-dependent mechanisms.

• Journal of Radiation Protection and Research
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• v.39 no.3
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• pp.142-149
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• 2014

Korea conducts a national health screening program to improve and check-up on public health and in recent years, the screening usage has been increased. Given the increased screening usage for radiographic exams, this study predicts the frequency of using radiographic exams and the exposure dose. This study estimates the usage of radiographic exams by isolating radiographic exams from the 2011 analysis of the national health insurance corporation, and estimates the public exposure dose by applying each procedure's dose table from UNSCEAR 2008. As a result of the analysis, in the 2011 National Health Screening, the average exposure dose per person is assumed to be 0.57 mSv, and depending on the type of screening program from the radiographic exam, an examinee could be exposed to between 0.2 mSv and 11.081 mSv. The frequency of using radiographic exposure was found to be 16,005,914 and the exposure dose was 6,311.76 person-Sv. The most frequent exam is the Chest X-ray, which was performed 1,070,567 (69.17%), and the UGI has the highest exposure dose at 5,217.94 person-Sv (82.67%). The outcome is categorized based on gender and age, excluding those under 39 years old. In all age groups, the screening usage and exposure dose are higher in females than in males. In particular, females between 50 and 54 years old have the highest screening usage (1,674,787, 10.5%) and exposure dose (701.59 person-Sv, 11.1%). As UGI accounts for 82.76% of procedures, except when done for medical purposes, if the government supports a voluntary UGI exam (which includes the UGI exam in the National Screening Program) or abolishes it completely, as seen overseas, the cost-effectiveness and validity of the UGI exam, as well as the exposure dose from the National Screening Program will all decrease significantly.