89 results on '"Yun Yeong Lee"'
Search Results
2. Trends of Colorectal Cancer Screening Rates in Korea: Korean National Cancer Screening Survey 2005–2020
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Bomi Park, Yun Yeong Lee, Soo Yeon Song, Hye Young Shin, Mina Suh, Kui Son Choi, and Jae Kwan Jun
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colorectal neoplasms ,early detection of cancer ,healthcare disparities ,social class ,Diseases of the digestive system. Gastroenterology ,RC799-869 - Abstract
Background/Aims: Screening for colorectal cancer (CRC) is important in reducing the morbidity and mortality of CRC. Thus, this study aimed to describe the trends of CRC screening in both organized and opportunistic settings in Korea from 2005 to 2020 according to sociodemographic characteristics. Methods: This study analyzed the data of adults aged 50 to 74 years from the Korean National Cancer Screening Survey. Trends for CRC screening rates (fecal immunochemical test [FIT] within the last year, double-contrast barium enema within the last 5 years, or colonoscopy within the last 10 years for 2005–2018 and FIT within the last year or colonoscopy within the last 10 years for 2019–2020) were analyzed using Joinpoint regression. The trends were also analyzed according to sociodemographic characteristics, including age, sex, monthly household income, education level, and residential area. Results: A total of 29,040 participants were included in the analysis. The CRC screening rate significantly increased from 25.0% to 60.1%, with an annual percent change (APC) of 9.2% between 2005 and 2014, followed by a nonsignificant increase to 64.4% between 2014 and 2020 (APC,1.7%). When the participants were stratified according to sociodemographic factors, the participants with higher household income and education levels generally had higher screening rates. Conclusions: There has been substantial improvement in CRC screening rates in the general Korean population. However, it is necessary to determine why the screening rate has stabilized since 2014 and identify barriers that cause disparities in CRC screening rates among populations with lower socioeconomic status.
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- 2022
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3. Abnormal Cholesterol Metabolism and Lysosomal Dysfunction Induce Age-Related Hearing Loss by Inhibiting mTORC1-TFEB-Dependent Autophagy
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Yun Yeong Lee, Jungho Ha, Young Sun Kim, Sivasubramanian Ramani, Siung Sung, Eun Sol Gil, Oak-Sung Choo, Jeong Hun Jang, and Yun-Hoon Choung
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age-related hearing loss ,autophagy ,hearing loss ,lysosome biogenesis ,mTORC1 ,transcription factor ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Cholesterol is a risk factor for age-related hearing loss (ARHL). However, the effect of cholesterol on the organ of Corti during the onset of ARHL is unclear. We established a mouse model for the ARHL group (24 months, n = 12) and a young group (6 months, n = 12). Auditory thresholds were measured in both groups using auditory brainstem response (ABR) at frequencies of 8, 16, and 32 kHz. Subsequently, mice were sacrificed and subjected to histological analyses, including transmission electron microscopy (TEM), H&E, Sudan Black B (SBB), and Filipin staining, as well as biochemical assays such as IHC, enzymatic analysis, and immunoblotting. Additionally, mRNA extracted from both young and aged cochlea underwent RNA sequencing. To identify the mechanism, in vitro studies utilizing HEI-OC1 cells were also performed. RNA sequencing showed a positive correlation with increased expression of genes related to metabolic diseases, cholesterol homeostasis, and target of rapamycin complex 1 (mTORC1) signaling in the ARHL group as compared to the younger group. In addition, ARHL tissues exhibited increased cholesterol and lipofuscin aggregates in the organ of Corti, lateral walls, and spiral ganglion neurons. Autophagic flux was inhibited by the accumulation of damaged lysosomes and autolysosomes. Subsequently, we observed a decrease in the level of transcription factor EB (TFEB) protein, which regulates lysosomal biosynthesis and autophagy, together with increased mTORC1 activity in ARHL tissues. These changes in TFEB and mTORC1 expression were observed in a cholesterol-dependent manner. Treatment of ARHL mice with atorvastatin, a cholesterol synthesis inhibitor, delayed hearing loss by reducing the cholesterol level and maintaining lysosomal function and autophagy by inhibiting mTORC1 and activating TFEB. The above findings were confirmed using stress-induced premature senescent House Ear Institute organ of Corti 1 (HEI-OC1) cells. The findings implicate cholesterol in the pathogenesis of ARHL. We propose that atorvastatin could prevent ARHL by maintaining lysosomal function and autophagy by inhibiting mTORC1 and activating TFEB during the aging process.
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- 2023
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4. Impact of COVID-19 on cancer screening in South Korea
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Kyeonmin Lee, Yun Yeong Lee, Mina Suh, Jae Kwan Jun, Bomi Park, Yeol Kim, and Kui Son Choi
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Medicine ,Science - Abstract
Abstract The coronavirus disease (COVID-19) pandemic significantly declined cancer screening rates worldwide. Its impact on the South Korean population is unclear, depending on socioeconomic status (SES), residence, and history of chronic disease. This study utilized data (2018–2020) from the Korean National Cancer Screening Survey, an annual cross-sectional study employing nationally representative random sampling. Cancer screening rates were defined as the proportion of the eligible population who received respective cancer screening within the last 1 year and investigated four major cancers (stomach, colorectal, breast, and cervical). Screening rates every year were compared with screening rate ratios (SRRs) and the corresponding 95% confidence intervals (CIs). Between 2019 and 2020, screening rates declined significantly by 23%, 17%, 12%, and 8% for colorectal cancer (SRR 0.77; 95% CI 0.73–0.82), stomach cancer (SRR 0.83; 95% CI 0.79–0.87), breast cancer (SRR 0.88; 95% CI 0.82–0.93), and cervical cancer (SRR 0.92; 95% CI 0.87–0.97), respectively. Regardless of cancer type, screening was significantly lower in metropolitan residents, those with higher SES, and, interestingly, those without a history of chronic diseases. The significant decline in cancer screening during the pandemic requires urgent political intervention to reduce the burden of future cancer incidence and mortality.
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- 2022
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5. Trends in breast cancer screening rates among Korean women: results from the Korean National Cancer Screening Survey, 2005-2020
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Soo Yeon Song, Yun Yeong Lee, Hye Young Shin, Bomi Park, Mina Suh, Kui Son Choi, and Jae Kwan Jun
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breast neoplasms ,early detection of cancer ,health care surveys ,mammography ,mass screening ,Medicine - Abstract
OBJECTIVES Since 2002, the Korean government has provided breast cancer screening as part of the National Cancer Screening Program. This study reported trends in the screening rate among Korean women from 2005 to 2020, including organized and opportunistic screening for breast cancer. METHODS Data from the Korean National Cancer Screening Survey, an annual cross-sectional nationwide survey, were collected using a structured questionnaire between 2005 and 2020. The study population included 23,702 women aged 40-74 years with no history of cancer. We estimated the screening rate based on the current recommendation of biennial mammographic screening for breast cancer. In addition, a joinpoint trend analysis was performed for breast cancer screening rates among various subgroups. RESULTS In 2020, the breast cancer screening rate was 63.5%, reflecting an annual increase of 7.72% (95% confidence interval 5.53 to 9.95) between 2005 and 2012, followed by non-significant trends thereafter. In particular, a significant decrease in the breast cancer screening rate was observed in the subgroups aged 50-59 years old, with 12-15 years of education, and living in rural areas. CONCLUSIONS Although there has been substantial improvement in breast cancer screening rates in Korean women, the trend has flattened in recent years. Therefore, continual efforts are required to identify subgroups with unmet needs and solve barriers to the uptake of breast cancer screening.
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- 2022
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6. Changes in cancer screening before and during COVID‐19: findings from the Korean National Cancer Screening Survey 2019 and 2020
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Thao Thi Kim Trinh, Yun Yeong Lee, Mina Suh, Jae Kwan Jun, and Kui Son Choi
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neoplasms ,mass screening ,covid-19 ,Medicine - Abstract
OBJECTIVES The coronavirus disease 2019 (COVID-19) pandemic has negatively affected every aspect of medical care. However, information regarding the impact of the pandemic on cancer screening is lacking. This study aimed to explore cancer screening changes by geographic region before and during the pandemic in Korea. METHODS Korean National Cancer Screening Survey data for 2019 and 2020 were used. Changes in the screening rate before and during the COVID-19 pandemic were calculated by subtracting the rate in 2020 from the rate in 2019. Multivariate logistic regression analyses examined the differences in screening rates at the national and 16 provincial levels before and after the COVID-19 outbreak. RESULTS The 1-year screening rates for the four types of cancer decreased during the pandemic (stomach cancer: -5.1, colorectal cancer: -3.8, breast cancer: -2.5, cervical cancer: -1.5%p). In metropolitan areas, the odds of undergoing screening tests during the pandemic were significantly lower than before the pandemic for stomach (adjusted odds ratio [aOR], 0.66; 95% confidence interval [CI], 0.56 to 0.76), colorectal (aOR, 0.63; 95% CI, 0.50 to 0.79), and breast cancers (aOR, 0.75; 95% CI, 0.60 to 0.94). Furthermore, the likelihood of undergoing stomach cancer screening during the pandemic was significantly lower than before the pandemic in non-metropolitan urban areas (aOR, 0.81; 95% CI, 0.70 to 0.94), while it was higher in rural areas (aOR, 1.54; 95% CI, 1.10 to 2.16). CONCLUSIONS Since the COVID-19 pandemic, the cancer screening rate has decreased significantly, especially in large cities. Public health efforts are required to improve cancer screening rates.
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- 2022
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7. Development of Intracorporeal Differentiation of Stem Cells to Induce One-Step Mastoid Bone Reconstruction during Otitis Media Surgeries
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Sung-Hee Park, Hantai Kim, Yun Yeong Lee, Yeon Ju Kim, Jeong Hun Jang, Oak-Sung Choo, and Yun-Hoon Choung
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mastoidectomy ,osteogenesis ,stromal vascular fraction cells ,polycaprolactone (PCL) scaffold ,autologous growth factor ,Organic chemistry ,QD241-441 - Abstract
Mastoidectomy is a surgical procedure for the treatment of chronic otitis media. This study investigated the ability of rat stromal vascular fraction cells (rSVF) in combination with polycaprolactone (PCL) scaffolds and osteogenic differentiation-enhancing blood products to promote the regeneration of mastoid bone defect. Twenty male Sprague Dawley rats were randomly divided according to obliteration materials: (1) control, (2) PCL scaffold only, (3) rSVFs + PCL, (4) rSVFs + PCL + platelet-rich plasma, and (5) rSVFs + PCL + whole plasma (WP). At 7 months after transplantation, the rSVFs + PCL + WP group showed remarkable new bone formation in the mastoid. These results indicate that SVFs, PCL scaffolds, and blood products accelerate bone regeneration for mastoid reconstruction. Autologous SVF cells with PCL scaffolds and autologous blood products are promising composites for mastoid reconstruction which can be easily harvested after mastoidectomy. With this approach, the reconstruction of mastoid bone defects can be performed right after mastoidectomy as a one-step procedure which can offer efficiency in the clinical field.
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- 2022
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8. Heat Shock Factor 1 Prevents Age-Related Hearing Loss by Decreasing Endoplasmic Reticulum Stress
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Yun Yeong Lee, Eun Sol Gil, In Hye Jeong, Hantai Kim, Jeong Hun Jang, and Yun-Hoon Choung
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age-related hearing loss ,apoptosis ,endoplasmic reticulum stress ,heat shock factor 1 ,heat shock protein ,Cytology ,QH573-671 - Abstract
Endoplasmic reticulum (ER) stress is a common stress factor during the aging process. Heat shock factor 1 (HSF1) plays a critical role in ER stress; however, its exact function in age-related hearing loss (ARHL) has not been fully elucidated. The purpose of the present study was to identify the role of HSF1 in ARHL. In this study, we demonstrated that the loss of inner and outer hair cells and their supporting cells was predominant in the high-frequency region (basal turn, 32 kHz) in ARHL cochleae. In the aging cochlea, levels of the ER stress marker proteins p-eIF2α and CHOP increased as HSF1 protein levels decreased. The levels of various heat shock proteins (HSPs) also decreased, including HSP70 and HSP40, which were markedly downregulated, and the expression levels of Bax and cleaved caspase-3 apoptosis-related proteins were increased. However, HSF1 overexpression showed significant hearing protection effects in the high-frequency region (basal turn, 32 kHz) by decreasing CHOP and cleaved caspase-3 and increasing the HSP40 and HSP70 proteins. These findings were confirmed by HSF1 functional studies using an auditory cell model. Therefore, we propose that HSF1 can function as a mediator to prevent ARHL by decreasing ER stress-dependent apoptosis in the aging cochlea.
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- 2021
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9. Type 1 Diabetes Induces Hearing Loss: Functional and Histological Findings in An Akita Mouse Model
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Yun Yeong Lee, Yeon Ju Kim, Eun Sol Gil, Hantai Kim, Jeong Hun Jang, and Yun-Hoon Choung
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hearing loss ,diabetes ,Akita ,Na+/K+-ATPase ,apoptosis ,Biology (General) ,QH301-705.5 - Abstract
The relationship between type 1 diabetes and hearing loss is not well known, although based on many pathological studies, type 2 diabetes induced hearing loss is associated with microcirculation problems in the inner ear. The purpose of this study was to investigate the correlation between type 1 diabetes and hearing loss through hearing function and immunohistochemical analyses using type 1 diabetic Akita or wild-type (WT) mice. The Akita mice had a significant increase in hearing thresholds, blood glucose, and insulin tolerance compared to WT mice. Histological analysis showed that the loss of cells and damage to mitochondria in the spiral ganglion neurons of Akita mice were significantly increased compared to WT. Also, the stria vascularis showed decreased thickness, loss of intermediate cells, and disturbance in blood capillary shape in the Akita mice. Moreover, a reduction in type I, II, and IV fibrocytes and Na+/K+-ATPase α1 expression in spiral ligament was also observed. Cleaved caspase-3 expression was highly expressed in spiral ganglion neurons. In conclusion, hearing loss in type 1 diabetes is caused not only by ion imbalance and blood flow disorders of cochlear endolymph, but through the degenerative nervous system via apoptosis-mediated cell death.
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- 2020
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10. Cisplatin-Induced Ototoxicity in Rats Is Driven by RIP3-Dependent Necroptosis
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Mi-Jin Choi, Hyunsook Kang, Yun Yeong Lee, Oak-Sung Choo, Jeong Hun Jang, Sung-Hee Park, Jong-Seok Moon, Seong Jun Choi, and Yun-Hoon Choung
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necroptosis ,cisplatin ,ototoxicity ,organ of Corti ,spiral ganglion neuron ,Cytology ,QH573-671 - Abstract
Cisplatin-induced early-onset ototoxicity is linked to hearing loss. The mechanism by which cisplatin causes ototoxicity remains unclear. The purpose of this study was to identify the involvement of receptor-interacting protein kinase (RIP)3-dependent necroptosis in cisplatin-induced ototoxicity in vitro and in vivo. Sprague−Dawley rats (SD, 8 week) were treated via intraperitoneal (i.p.) injection with cisplatin (16 mg/kg for 1 day), and their hearing thresholds were measured by the auditory brainstem response (ABR) method. Hematoxylin and eosin (H & E) staining, immunohistochemistry, and western blots were performed to determine the effect of cisplatin-induced ototoxicity on cochlear morphology. Inhibitor experiments with necrostatin 1 (Nec-1) and Z-VAD were also performed in HEI-OC1 cell line. H&E stains revealed that the necroptotic changes were increased in the organ of Corti (OC) and spiral ganglion neurons (SGNs). Moreover, immunohistochemistry and western blot analysis showed that cisplatin treatment increased the protein levels of RIP3 in both OCs and SGNs. The treatment of Nec-1, a selective RIP1 inhibitor, resulted in markedly suppression of cisplatin-induced cell death in HEI-OC1 cells, whereas Z-VAD treatment did not change the cisplatin-induced cell death. Our results suggest that RIP3-dependent necroptosis was substantial in cisplatin-induced ototoxicity; inner cochlear regions, the OCs, and SGNs were especially sensitive to necroptosis.
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- 2019
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11. Evaluation of Biohydrogen Production Using Various Inoculum Sources
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Geumhee Kim, Jiho Lee, Hyoju Yang, Yun-Yeong Lee, Yoonyong Yang, Sungho Choi, Moonsuk Hur, Byounghee Lee, and Kyung-Suk Cho
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Applied Microbiology and Biotechnology ,Microbiology ,Biotechnology - Published
- 2022
12. Abbas Kiarostami’s Close-up and the Poetics of Cinematic (Re)constitution
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Yun-yeong Lee
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- 2022
13. Dynamics of bacterial functional genes and community structures during rhizoremediation of diesel-contaminated compost-amended soil
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Hyoju Yang, Kyung Suk Cho, Jiho Lee, Yoonjoo Seo, Minyoung Ha, and Yun Yeong Lee
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Environmental Engineering ,Compost ,Environmental remediation ,Chemistry ,Composting ,Soil organic matter ,Amendment ,General Medicine ,Contamination ,engineering.material ,Zea mays ,Soil contamination ,Soil ,chemistry.chemical_compound ,Biodegradation, Environmental ,Petroleum ,Agronomy ,Soil water ,engineering ,Soil Pollutants ,Total petroleum hydrocarbon ,Soil Microbiology - Abstract
The objective of this study was to characterize the effects of organic soil amendment (compost) on bacterial populations associated with petroleum hydrocarbon (PH) degradation and nitrous oxide (N2O) dynamics via pot experiments. Soil was artificially contaminated with diesel oil at total petroleum hydrocarbon (TPH) concentration of 30,000 mg·kg-soil-1 and compost was mixed with the contaminated soil at a 1:9 ratio (w/w). Maize seedlings were planted in each pot and a total of ten pots with two treatments (compost-amended and unamended) were prepared. The pot experiment was conducted for 85 days. The compost-amended soil had a significantly higher TPH removal efficiency (51.1%) than unamended soil (21.4%). Additionally, the relative abundance of the alkB gene, which is associated with PH degradation, was higher in the compost-amended soil than in the unamended soil. Similarly, cnorB and nosZ (which are associated with nitric oxide (NO) and N2O reduction, respectively) were also highly upregulated in the compost-amended soil. Moreover, the compost-amended soil exhibited higher richness and evenness indices, indicating that bacterial diversity was higher in the amended soil than in the unamended soil. Therefore, our findings may contribute to the development of strategies to enhance remediation efficiency and greenhouse gas mitigation during the rhizoremediation of diesel-contaminated soils.
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- 2021
14. Characterization of CH4-oxidizing and N2O-reducing Bacterial Consortia Enriched from the Rhizospheres of Maize and Tall Fescue
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Ye ji Kim, Kyung Suk Cho, Seo Young Kim, Soojung Lee, and Yun Yeong Lee
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Rhizosphere ,chemistry.chemical_compound ,Chemistry ,Environmental chemistry ,Oxidizing agent ,Nitrous oxide ,Applied Microbiology and Biotechnology ,Microbiology ,Methane ,Biotechnology - Published
- 2021
15. Effect of Novosphingobium sp. CuT1 inoculation on the rhizoremediation of heavy metal- and diesel-contaminated soil planted with tall fescue
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Soo Yeon Lee, Yun-Yeong Lee, and Kyung-Suk Cho
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Health, Toxicology and Mutagenesis ,Environmental Chemistry ,General Medicine ,Pollution - Abstract
Rhizoremediation is a promising method based on the synergism between plant and rhizobacteria to remediate soil co-contaminated with heavy metals and total petroleum hydrocarbons (TPHs). A plant growth-promoting (PGP) rhizobacterium with diesel-degrading capacity and heavy metal tolerance was isolated from the rhizosphere of tall fescue (Festuca arundinacea L.), after which the effects of its inoculation on rhizoremediation performance were evaluated in heavy metal- and diesel-contaminated soil planted with tall fescue. The bacterial isolate (Novosphingobium sp. CuT1) was characterized by its indole-3-acetic acid (IAA) production, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity, and siderophore productivity as PGP traits. CuT1 was able to grow on 1/10 LB-agar plates containing 5 mM of Cu or 5 mM of Pb. To evaluate the remediation effect of heavy metal- and diesel-contaminated soil by CuT1 inoculation, the experimental conditions were prepared as follows. The soil was artificially contaminated with heavy metals (Cu and Pb) at a final concentration of 500 ppm. The soil was then further contaminated with diesel at final concentrations of 0, 10,000, and 30,000 ppm. Finally, all plots were planted with tall fescue, a representative hyperaccumulating plant. Compared to the rhizoremediation performance of the co-contaminated soil (Cu + Pb + diesel) without inoculation, the bioavailable Cu concentrations in the soil and the tall fescue biomass were significantly increased in CuT1 inoculation. Additionally, the root growth of tall fescue was also promoted in CuT1 inoculation. Correlation analysis showed that Cu bioavailability and bioconcentration factor were positively correlated with CuT1 inoculation. The diesel removal efficiency showed a positive correlation with CuT1 inoculation, although the diesel removal was below 30%. CuT1 inoculation was positively correlated with IAA and dehydrogenase activity in the soil. Moreover, the dry biomass of the tall fescue's roots was highly associated with CuT1 inoculation. Collectively, our findings suggest that Novosphingobium sp. CuT1 can be utilized as an applicable bioresource to enhance rhizoremediation performance in heavy metal- and TPH-contaminated soils.
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- 2022
16. Impact of Awareness of Breast Density on Perceived Risk, Worry, and Intentions for Future Breast Cancer Screening among Korean Women
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Anh Thi Ngoc Tran, Kui Son Choi, Eunji Choi, Yun Yeong Lee, Chan Wha Lee, Yeol Kim, Ji Hae Hwang, and Mina Suh
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Adult ,Cancer Research ,Breast Neoplasms ,Logistic regression ,Dense breast ,03 medical and health sciences ,Breast cancer screening ,0302 clinical medicine ,Breast cancer ,Risk Factors ,Breast Cancer ,Cancer screening ,medicine ,Humans ,030212 general & internal medicine ,skin and connective tissue diseases ,Cancer worry ,Early Detection of Cancer ,Aged ,Breast Density ,medicine.diagnostic_test ,business.industry ,Cancer ,Odds ratio ,Awareness ,Middle Aged ,medicine.disease ,Perceived risks ,Risk perception ,Knowledge ,Oncology ,030220 oncology & carcinogenesis ,Screening ,Original Article ,Female ,Ordered logit ,business ,Demography - Abstract
PurposeThis study sought to examine perceived risk and concerns for breast cancer according to awareness of breast density and states thereof among Korea women and to identify the impact of such awareness on screening intentions. Materials and MethodsThis study was based on the 2017 Korean National Cancer Screening Survey of a nationally representative and randomly selected sample of Koreans. Ordinal logistic regression was conducted to examine associations for awareness of and knowledge on breast density in relation to psychological factors. Multivariate logistic regression analyses were conducted to investigate significant factors associated with intentions to undergo breast cancer screening. ResultsAmong a total of 1,609 women aged 40-69 years, 62.0% were unaware of their breast density, and only 29.7% had good breast density knowledge. Awareness of one’s breast density and knowledge about breast density were positively associated with perceptions of absolute and comparative risk and cancer worry. Women aware of their breast density (adjusted odds ratio [aOR], 1.35 for women aware of having a non-dense breast; aOR, 4.17 for women aware of having a dense breast) and women with a good level of breast density knowledge (aOR, 1.65) were more likely to undergo future breast cancer screening. ConclusionBreast density awareness and knowledge showed positive associations with psychological factors and breast cancer screening intentions. However, the majority of Korean women were not aware of their breast density status and demonstrated poor knowledge about breast density. These results demonstrate a need for better health communication concerning breast density.
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- 2021
17. Effect of statin on age-related hearing loss via drug repurposing
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Oak-Sung Choo, Yun Yeong Lee, Young Sun Kim, Yeon Ju Kim, Dong Ha Lee, Hantai Kim, Jeong Hun Jang, and Yun-Hoon Choung
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Mice ,Oxidative Stress ,Drug Repositioning ,Quality of Life ,Animals ,Cell Biology ,Hydroxymethylglutaryl-CoA Reductase Inhibitors ,Presbycusis ,Molecular Biology - Abstract
Hearing loss in the elderly cause communication difficulties, decreased quality of life, isolation, loneliness and frustration. The aim of our study was to investigate the effect of drug repurposing candidates in aging mouse. The selected candidate drugs for age-related hearing loss (ARHL) included atorvastatin (AS) and sarpogrelate. Monotherapy or fixed dose combination (FDC) products were administered via oral gavage for 6 consecutive months. Auditory outcomes showed significant hearing preservation in AS-treated aging mice compared to aging control, especially in the early stages of ARHL in both 8 and 16 kHz frequencies. However, none of the FDC products were able to prevent ARHL regardless of AS involvement. In aging mice, damage and dysfunction of mitochondria was noted as well as reactive oxygen species overproduction leading to oxidative stress and intrinsic apoptosis. These processes of ARHL were significantly prevented with administration of AS. Normal structures of mitochondria were maintained, and antioxidant activity were proceeded by activation of HSF1/Sirt1 pathway. Our study suggests that AS is a promising drug repurposing candidate to delay the progression of ARHL.
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- 2022
18. Acceptance on colorectal cancer screening upper age limit in South Korea
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Kyeong-Min Lee, Yun Yeong Lee, Yeol Kim, Mina Suh, Xuan Quy Luu, and Kui Son Choi
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Adult ,Male ,Population ,Observational Study ,03 medical and health sciences ,Elderly ,0302 clinical medicine ,Republic of Korea ,Cancer screening ,Humans ,Medicine ,Family history ,education ,Early Detection of Cancer ,Mass screening ,Aged, 80 and over ,education.field_of_study ,business.industry ,Fecal occult blood ,Gastroenterology ,Colonoscopy ,Odds ratio ,General Medicine ,Cancer early detection ,Patient Acceptance of Health Care ,Colorectal cancer ,Occult Blood ,030220 oncology & carcinogenesis ,Patients dropouts ,Marital status ,Population study ,Female ,030211 gastroenterology & hepatology ,Patient participation ,Colorectal Neoplasms ,business ,Demography - Abstract
BACKGROUND The Korea National Cancer Screening Program currently provides screening for colorectal cancer (CRC) for adults older than 50 years with no upper age limit. In general, people are likely to only pay attention to the benefits of cancer screening and to neglect its risks. Most consider the benefits of cancer screening as being far greater than the risks and are unaware that any potential benefits and harms can vary with age. AIM To report acceptance of an upper age limit for CRC screening and factors associated therewith among cancer-free individuals in Korea. METHODS The present study analyzed data from the Korea National Cancer Screening Survey 2017, a nationally representative random sample of 4500 Korean individuals targeted for screening for the five most common types of cancer. A total of 1922 participants were included in the final analysis. The baseline characteristics of the study population are presented as unweighted numbers and weighted proportions. Both univariate and multivariate logistic regression models were developed to examine factors related with acceptance of an upper age limit for CRC screening; subgroup analysis was also applied. RESULTS About 80% (1554/1922) of the respondents agreed that CRC screening should not be offered for individuals older than 80 years. Specifically, those who had never been screened for CRC had the highest acceptance rate (91%). Overall, screening history for CRC [screened by both fecal occult blood test and colonoscopy, adjusted odds ratio (aOR) = 0.33, 95%CI: 0.22-0.50] and other cancers (aOR = 0.55, 95%CI: 0.34-0.87), as well as a family history of cancer (aOR = 0.66, 95%CI: 0.50-0.87), were negatively associated with acceptance of an upper age limit for CRC screening. In contrast, metropolitan residents (aOR = 1.86, 95%CI: 1.29-2.68) and people who exercised regularly (aOR = 1.42, 95%CI: 1.07-1.89) were more likely to accept an upper age limit. After subgrouping, we found gender, marital status, and lifetime smoking history among never-screened individuals and residential region, family history of cancer, and physical activity among never-screened individuals to be associated with acceptance of an upper age limit. CONCLUSION This study describes acceptance of an upper age limit for CRC screening and factors associated with it, and provides perspectives that should be considered, in addition to scientific evidence, when developing population-based cancer screening policies and programs.
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- 2020
19. Removal of particulate matter from pork belly grilling gas using an orifice wet scrubber
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Shi nae Jang, Kyung Suk Cho, Yun Yeong Lee, Jihyun Kwon, Yoonjoo Seo, Jeonghee Yun, and Hyung Joo Park
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Restaurants ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Swine ,0211 other engineering and technologies ,Scrubber ,02 engineering and technology ,01 natural sciences ,Waste Management ,Particle mass ,Air Pollution ,Republic of Korea ,Animals ,Cooking ,021108 energy ,Particle Size ,0105 earth and related environmental sciences ,Air Pollutants ,Wet scrubber ,General Medicine ,Particulates ,Pulp and paper industry ,Red Meat ,Environmental science ,Particulate Matter ,Body orifice - Abstract
Grilling restaurants are a major contributor to airborne particulate matter (PM) in metropolitan areas. In this study, the removal of PM during the grilling of pork belly using an orifice scrubber, which is a form of gas-induced spray scrubber, was assessed. During grilling, the particle mass concentration was the highest for 1.0 2.5 μm (7.0%). The PM removal efficiency of the orifice scrubber at a gas flow of 4.5 m3 min-1 was > 99.7% for PM ≥ 2.5 μm, 89.4% for 1.0 < PM ≤ 2.5 μm, 62.1% for 0.5 < PM ≤ 1.0, and 36.5% for PM ≤ 0.5 μm. Although further research is necessary to optimize its use, the orifice scrubber offers a user-friendly technology for the control of PM in small grilling restaurants because of its simple design, uncomplicated operation, and satisfactory PM removal performance.
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- 2020
20. Mitochondrial nucleoid remodeling and biogenesis are regulated by the p53-p21WAF1-PKCζ pathway in p16INK4a-silenced cells
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Do Wan Kim, In Kyoung Lim, Yun Yeong Lee, Jae Youn Cheong, Yeon Seung Choi, Kye Yong Song, and Min Sook Ryu
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Senescence ,Aging ,Mitochondrial biogenesis ,Nucleoid ,Cell Biology ,NRF1 ,TFAM ,Mitochondrion ,Biology ,Reprogramming ,Mitochondrial nucleoid ,Cell biology - Abstract
Mitochondrial dysfunction is linked to age-related senescence phenotypes. We report here the pathway increasing nucleoid remodeling and biogenesis in mitochondria during the senescence of foreskin human diploid fibroblasts (fs-HDF) and WI-38 cells. Replicative senescence in fs-HDF cells increased mitochondrial nucleoid remodeling as indicated by 5-bromo-2'-deoxyuridine (BrdU) incorporation and mitochondrial transcription factor A (TFAM) expression in enlarged and fused mitochondria. Mitochondrial nucleoid remodeling was accompanied by mitochondrial biogenesis in old cells, and the expression levels of OXPHOS complex-I, -IV and -V subunits, PGC-1α and NRF1 were greatly increased compared to young cells. Activated protein kinase C zeta (PKCζ) increased mitochondrial activity and expressed phenotypes of delayed senescence in fs-HDF cells, but not in WI-38 cells. The findings were reproduced in the doxorubicin-induced senescence of young fs-HDF and WI-38 cells via the PKCζ-LKB1-AMPK signaling pathway, which was regulated by the p53-p21WAF1 pathway when p16INK4a was silenced. The signaling enhanced PGC-1α-NRF1-TFAM axis in mitochondria, which was demonstrated by Ingenuity Pathway Analysis of young and old fs-HDF cells. Activation of the p53-p21WAF1 pathway and silencing of p16INK4a are responsible for mitochondrial reprogramming in senescent cells, which may be a compensatory mechanism to promote cell survival under senescence stress.
- Published
- 2020
21. Dynamics of Nitrogen Compounds and Functional Genes in a Nitrification- Denitrification Coupling Process
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Yun Yeong Lee, Ji Hyeon Kwon, Hyung Joo Park, and Kyung Suk Cho
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Denitrification ,chemistry.chemical_element ,Functional genes ,Nitrous oxide ,Applied Microbiology and Biotechnology ,Microbiology ,Nitrogen ,chemistry.chemical_compound ,Coupling (computer programming) ,chemistry ,Environmental chemistry ,Scientific method ,Sewage treatment ,Nitrification ,Biotechnology - Published
- 2020
22. Seasonal Dynamics of Bacterial Community Structure in Diesel Oil-Contaminated Soil Cultivated with Tall Fescue (
- Author
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Yun-Yeong, Lee, Soo Yeon, Lee, Sang Don, Lee, and Kyung-Suk, Cho
- Subjects
Festuca ,Soil ,Biodegradation, Environmental ,Petroleum ,Lolium ,Soil Pollutants ,Seasons ,Gasoline ,Hydrocarbons ,Soil Microbiology - Abstract
The objective of this study was to explore the seasonal characteristics of rhizoremediation and the bacterial community structure over the course of a year in soil contaminated with diesel oil. The soil was contaminated with diesel oil at a total petroleum hydrocarbon (TPH) concentration of 30,000 mg-TPH·kg-soil
- Published
- 2022
23. Trends in cervical cancer screening rates among Korean women: results of the Korean National Cancer Screening Survey, 2005-2020
- Author
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Hye Young Shin, Yun Yeong Lee, Soo Yeon Song, Bomi Park, Mina Suh, Kui Son Choi, and Jae Kwan Jun
- Subjects
Vaginal Smears ,Cross-Sectional Studies ,Oncology ,Republic of Korea ,Obstetrics and Gynecology ,Humans ,Uterine Cervical Neoplasms ,Female ,General Medicine ,Early Detection of Cancer ,Papanicolaou Test - Abstract
This study aimed to analyze the trends in cervical cancer screening rates, including organized and opportunistic cancer screening rates, with the Papanicolaou test among Korean women.Data were collected from a nationwide, cross-sectional, Korean National Cancer Screening Survey. To evaluate the cervical cancer screening rates, we used the screening approach of "The cervical cancer screening rate was 56.0% in 2020. From 2005 to 2013, there was a rising trend in cervical cancer screening rates (APC=2.70%, 95% confidence interval [CI]:1.05 to 4.38), followed by a falling trend (APC=-2.67%, 95% CI:-4.3 to -1.01). The falling trend was significantly associated with age (≥40 years), education level (below the 15th grade), household income (below the middle-income level), and residence (all residential areas).The recent falling trend was more common in women with a low socioeconomic status, which suggests that there is a socioeconomic gap in cervical cancer screening. Moreover, young women in their thirties had a low screening rate. Therefore, an active participation strategy for women vulnerable to cervical cancer is required.
- Published
- 2021
24. Heat Shock Factor 1 Prevents Age-Related Hearing Loss by Decreasing Endoplasmic Reticulum Stress
- Author
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Hantai Kim, Yun Yeong Lee, Yun-Hoon Choung, In Hye Jeong, Jeong Hun Jang, and Eun Sol Gil
- Subjects
Male ,QH301-705.5 ,heat shock protein ,CHOP ,Article ,Mice ,Heat Shock Transcription Factors ,Heat shock protein ,otorhinolaryngologic diseases ,Animals ,Biology (General) ,HSF1 ,Cochlea ,Heat-Shock Proteins ,Chemistry ,Caspase 3 ,Endoplasmic reticulum ,fungi ,apoptosis ,General Medicine ,Presbycusis ,Cell biology ,Hsp70 ,Mice, Inbred C57BL ,age-related hearing loss ,heat shock factor 1 ,Apoptosis ,Unfolded protein response ,Unfolded Protein Response ,endoplasmic reticulum stress - Abstract
Endoplasmic reticulum (ER) stress is a common stress factor during the aging process. Heat shock factor 1 (HSF1) plays a critical role in ER stress, however, its exact function in age-related hearing loss (ARHL) has not been fully elucidated. The purpose of the present study was to identify the role of HSF1 in ARHL. In this study, we demonstrated that the loss of inner and outer hair cells and their supporting cells was predominant in the high-frequency region (basal turn, 32 kHz) in ARHL cochleae. In the aging cochlea, levels of the ER stress marker proteins p-eIF2α and CHOP increased as HSF1 protein levels decreased. The levels of various heat shock proteins (HSPs) also decreased, including HSP70 and HSP40, which were markedly downregulated, and the expression levels of Bax and cleaved caspase-3 apoptosis-related proteins were increased. However, HSF1 overexpression showed significant hearing protection effects in the high-frequency region (basal turn, 32 kHz) by decreasing CHOP and cleaved caspase-3 and increasing the HSP40 and HSP70 proteins. These findings were confirmed by HSF1 functional studies using an auditory cell model. Therefore, we propose that HSF1 can function as a mediator to prevent ARHL by decreasing ER stress-dependent apoptosis in the aging cochlea.
- Published
- 2021
25. Trends in breast cancer screening rates among Korean women: results from the Korean National Cancer Screening Survey (KNCSS), 2005-2020
- Author
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Soo Yeon, Song, Yun Yeong, Lee, Hye Young, Shin, Bomi, Park, Mina, Suh, Kui Son, Choi, and Jae Kwan, Jun
- Subjects
General Medicine - Abstract
Since 2002, the Korean government has provided breast cancer screening as part of the National Cancer Screening Program. This study reported the screening rate trends among Korean women from 2005 to 2020, including organized and opportunistic screening for breast cancer.Data from the Korean National Cancer Screening Survey, an annual cross-sectional nationwide survey, was collected using a structured questionnaire between 2005 and 2020. The study population included 23,702 women aged 40-74 years with no history of cancer. We estimated the screening rate with the current recommendation of biennial mammographic screening for breast cancer. In addition, a joinpoint trend analysis was performed for breast cancer screening rates using subgroup analysis.In 2020, the breast cancer screening rate was 63.5%, which showed an annual increase of 7.72% (95% confidence interval 5.53% to 9.95%) between 2005 and 2012, followed by non-significant trends thereafter. In particular, a significant decrease in the breast cancer screening rate was observed in the subgroups aged 50-59 years old, with 12-15 years of education, and living in rural areas.Although there has been substantial improve in breast cancer screening rates in Korean women, the recent trend has flattened. Therefore, efforts are continually required to find out unmet subgroups and solve barriers for uptake of breast cancer screening.
- Published
- 2022
26. Characterization of Heavy Metal Tolerant and Plant Growth-Promoting Rhizobacteria Isolated from Soil Contaminated with Heavy Metal and Diesel
- Author
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Soo Yeon Lee, Yun-Yeong Lee, and Kyung Suk Cho
- Subjects
Metal ,Diesel fuel ,visual_art ,Environmental chemistry ,visual_art.visual_art_medium ,Environmental science ,Heavy metals ,Contamination ,Rhizobacteria ,Applied Microbiology and Biotechnology ,Microbiology ,Soil contamination ,Biotechnology - Published
- 2021
27. Removal of Particulate Matter from Meat-Grilling Fumes Using a Mirror-Symmetrical Multicompartment Scrubber
- Author
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Soo Kyung Kang, Yun Yeong Lee, Kyung-Suk Cho, and Shi nae Jang
- Subjects
Pressure drop ,Environmental Engineering ,Environmental engineering ,Environmental Chemistry ,Aerodynamic diameter ,Environmental science ,Scrubber ,Particulates ,General Environmental Science ,Civil and Structural Engineering - Abstract
In megacities and urban areas, grilling restaurants have been recognized as major sources of particulate matter (PM) with an aerodynamic diameter under 2.5 μm (PM2.5). To reduce PM emission...
- Published
- 2021
28. Effect of upflow and downflow baffle configuration on particulate matter removal in a mirror-symmetrical multi-compartment scrubber
- Author
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In-Sook Lee, Kyung Suk Cho, Yun-Yeong Lee, Soo Yeon Lee, and Soo-Kyung Kang
- Subjects
Pressure drop ,Air Pollutants ,Environmental Engineering ,Environmental engineering ,Scrubber ,Baffle ,General Medicine ,Particulates ,Volumetric flow rate ,Air Pollution ,Environmental science ,Particulate Matter ,Water volume ,Air quality index - Abstract
Control over particulate matter (PM) emission from grilling is required for improving public health and air quality. The performance of mirror-symmetrical multi-compartment scrubbers with an upflow (U-type) and downflow baffle (D-type) configuration was evaluated for PM emission control from grilling at a flow rate of 30 m3 min-1. The PM removal efficiency of the U-type scrubber was the highest when the water level was 8 cm (95.6%), and the pressure drops recorded at the water levels of 6, 8 and 10 cm were 103, 122 and 153 mmH2O, respectively. Although PM removal efficiency of the D-type scrubber was over 91.0% at the water levels of 8, 10 and 12 cm, the pressure drops were 124, 142 and 185 mmH2O, respectively. A comprehensive evaluation of the water volume, pressure drop and PM removal performance, as well as device size, revealed that the U-type scrubber with a PM removal efficiency of 92% or higher and a pressure drop of 122 mmH2O or lower at the water levels of 6-8 cm was more economical for removing PM from grilling gas than the D-type scrubber.
- Published
- 2021
29. Nitrifying-genes Dynamics in the Enriched Bacterial Consortium Inoculated with Humic Soil
- Author
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Yun-Yeong Lee, Yoonjoo Seo, Kyung Suk Cho, and Hyungjoo Choi
- Subjects
chemistry.chemical_compound ,chemistry ,Inoculation ,Dynamics (mechanics) ,Nitrification ,Functional genes ,Ammonium ,Nitrite ,Applied Microbiology and Biotechnology ,Microbiology ,Gene ,Biotechnology - Published
- 2019
30. 서평 『인생극장』의 사회학적 상상력 노명우. 『인생극장: 막이 내리고 비로소 시작되는 아버지, 어머니의 인생이야기』. 사계절. 2018
- Author
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Yun-yeong Lee
- Subjects
Sociology ,Theology - Published
- 2019
31. Trends in cervical cancer screening rates among Korean women: results of the Korean National Cancer Screening Survey, 2005-2020.
- Author
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Hye Young Shin, Yun Yeong Lee, Soo Yeon Song, Bomi Park, Mina Suh, Kui Son Choi, and Jae Kwan Jun
- Subjects
- *
EARLY detection of cancer , *KOREANS , *CERVICAL cancer , *PAP test , *RESIDENTIAL areas - Abstract
Objective: This study aimed to analyze the trends in cervical cancer screening rates, including organized and opportunistic cancer screening rates, with the Papanicolaou test among Korean women. Methods: Data were collected from a nationwide, cross-sectional, Korean National Cancer Screening Survey. To evaluate the cervical cancer screening rates, we used the screening approach of " cervical cancer screening rate with recommendation," defined as the proportion of women who underwent the Papanicolaou test during the previous 2 years according to the Protocol of National Cancer Screening Program for Cervical Cancer in Korea. The joinpoint regression analysis, which describes the annual percent change (APC), was performed to detect significant changes in cervical cancer screening rates in women aged 30-74 years during 2005-2020. Results: The cervical cancer screening rate was 56.0% in 2020. From 2005 to 2013, there was a rising trend in cervical cancer screening rates (APC=2.70%, 95% confidence interval [CI]:1.05 to 4.38), followed by a falling trend (APC=-2.67%, 95% CI:-4.3 to -1.01). The falling trend was significantly associated with age (≥40 years), education level (below the 15 th grade), household income (below the middle-income level), and residence (all residential areas). Conclusion: The recent falling trend was more common in women with a low socioeconomic status, which suggests that there is a socioeconomic gap in cervical cancer screening. Moreover, young women in their thirties had a low screening rate. Therefore, an active participation strategy for women vulnerable to cervical cancer is required. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
32. Type 1 Diabetes Induces Hearing Loss: Functional and Histological Findings in An Akita Mouse Model
- Author
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Eun Sol Gil, Yun-Hoon Choung, Hantai Kim, Yeonju Kim, Yun Yeong Lee, and Jeong Hun Jang
- Subjects
medicine.medical_specialty ,Endolymph ,Hearing loss ,Na+/K+-ATPase ,Medicine (miscellaneous) ,030209 endocrinology & metabolism ,Type 2 diabetes ,Article ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Diabetes mellitus ,medicine ,otorhinolaryngologic diseases ,Akita ,Inner ear ,030223 otorhinolaryngology ,lcsh:QH301-705.5 ,Spiral ganglion ,hearing loss ,Type 1 diabetes ,diabetes ,business.industry ,apoptosis ,medicine.disease ,medicine.anatomical_structure ,Endocrinology ,lcsh:Biology (General) ,Spiral ligament ,sense organs ,medicine.symptom ,business - Abstract
The relationship between type 1 diabetes and hearing loss is not well known, although based on many pathological studies, type 2 diabetes induced hearing loss is associated with microcirculation problems in the inner ear. The purpose of this study was to investigate the correlation between type 1 diabetes and hearing loss through hearing function and immunohistochemical analyses using type 1 diabetic Akita or wild-type (WT) mice. The Akita mice had a significant increase in hearing thresholds, blood glucose, and insulin tolerance compared to WT mice. Histological analysis showed that the loss of cells and damage to mitochondria in the spiral ganglion neurons of Akita mice were significantly increased compared to WT. Also, the stria vascularis showed decreased thickness, loss of intermediate cells, and disturbance in blood capillary shape in the Akita mice. Moreover, a reduction in type I, II, and IV fibrocytes and Na+/K+-ATPase &alpha, 1 expression in spiral ligament was also observed. Cleaved caspase-3 expression was highly expressed in spiral ganglion neurons. In conclusion, hearing loss in type 1 diabetes is caused not only by ion imbalance and blood flow disorders of cochlear endolymph, but through the degenerative nervous system via apoptosis-mediated cell death.
- Published
- 2020
33. Effects of carbon source, C/N ratio, nitrate, temperature, and pH on N2O emission and functional denitrifying genes during heterotrophic denitrification
- Author
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Hyungjoo Choi, Yun Yeong Lee, and Kyung Suk Cho
- Subjects
Environmental Engineering ,Denitrification ,Heterotroph ,Functional genes ,04 agricultural and veterinary sciences ,General Medicine ,Nitrous oxide ,010501 environmental sciences ,01 natural sciences ,Denitrifying bacteria ,chemistry.chemical_compound ,Nitrate ,chemistry ,Environmental chemistry ,Carbon source ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,0105 earth and related environmental sciences - Abstract
The effects of operational parameters such as carbon source, C/N ratio, initial nitrate concentration, temperature, and pH value on heterotrophic denitrification and functional denitrifying genes w...
- Published
- 2018
34. Atorvastatin Prevents Hearing Impairment in the Presence of Hyperlipidemia
- Author
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Yun Yeong Lee, Jeong Hun Jang, Oak-Sung Choo, Yeonju Kim, Yup Kang, Yun-Hoon Choung, and Eun Sol Gil
- Subjects
0301 basic medicine ,Male ,medicine.medical_specialty ,Atorvastatin ,SOD2 ,Apoptosis ,Hyperlipidemias ,Diet, High-Fat ,Antioxidants ,Superoxide dismutase ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Internal medicine ,Hyperlipidemia ,otorhinolaryngologic diseases ,Medicine ,Animals ,Humans ,cardiovascular diseases ,Hearing Loss ,Molecular Biology ,Cochlea ,Aged ,chemistry.chemical_classification ,Reactive oxygen species ,biology ,business.industry ,nutritional and metabolic diseases ,Cell Biology ,medicine.disease ,Mitochondria ,Disease Models, Animal ,Oxidative Stress ,030104 developmental biology ,Endocrinology ,chemistry ,biology.protein ,Sensorineural hearing loss ,business ,Reactive Oxygen Species ,Oxidation-Reduction ,030217 neurology & neurosurgery ,medicine.drug ,Signal Transduction - Abstract
It is known that hyperlipidemia is a risk factor for sensorineural hearing loss. However, the biological mechanisms underlying hyperlipidemia and hearing impairment have not been completely elucidated in the cochlea. Based on our previous study of human subjects, elderly people taking drugs for hyperlipidemia showed better hearing than those not taking any medications. We hypothesized that drugs for hyperlipidemia, such as statins, may have the potential to prevent hearing impairment. The aim of this study was to investigate the correlation between hyperlipidemia and hearing impairment and the hearing preservation effect of atorvastatin using a hyperlipidemic mouse model with diet-induced obesity (DIO). Here, we demonstrate that DIO mice had a significant hearing impairment as well as increased levels of reactive oxygen species (ROS) and hair cell death due to reduced levels of pAKT and superoxide dismutase 2 (SOD2). However, these changes were significantly prevented by atorvastatin. In mechanistic studies, oxidative stress-induced intrinsic apoptosis was decreased by the high expression of nrf2 and antioxidant genes, which improved mitochondrial function and ROS via activation of the PI3K-AKT pathway by atorvastatin. Therefore, atorvastatin has the potential to prevent hearing impairment via redox balance in the presence of hyperlipidemia.
- Published
- 2019
- Full Text
- View/download PDF
35. Imaginaires nés des lieux hétérotopiques chez Kim Ki-duk
- Author
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Yun-yeong Lee
- Subjects
Sociology and Political Science ,Arts and Humanities (miscellaneous) ,Demography - Abstract
Les espaces cinematographiques singuliers que le cinema de Kim Ki-duk a explores peuvent etre qualifies d’heterotopiques. Ils sont non seulement grotesques, maussades et excentriques, mais aussi reellement situes en Coree, a savoir localisables. Une part notable du travail de ce metteur en scene consiste a reperer des heterotopies au sein de la societe coreenne, a les employer ensuite pour construire ses espaces cinematographiques, avant d’appliquer leurs particularites aux personnages, aux evenements, voire aux imaginaires. Un autre lieu, le corps, qui subit chez Kim toutes les formes de violence, temoigne de la rigidite sociale mortifere. D’autres imaginaires, nes principalement des lieux heterotopiques dans le cinema de Kim, contestent la societe coreenne, ainsi que son imaginaire typique.
- Published
- 2017
36. Characterization of odor-associated bacterial community in automobile HVAC (Heating, Ventilation and Air Conditioning) systems
- Author
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Yun-Yeong Lee, Hee Wook Ryu, Hyungjoo Choi, JongRae Cho, Kyung-Suk Cho, Kwangmo Seong, and Jeonghee Yun
- Subjects
Engineering ,Odor ,Waste management ,business.industry ,HVAC ,Energy recovery ventilation ,business - Published
- 2017
37. Evaluation of denitrification performance and bacterial community of a sequencing batch reactor under intermittent aeration
- Author
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Hyung Joo Park, Yun Yeong Lee, Ji Hyeon Kwon, and Kyung Suk Cho
- Subjects
0301 basic medicine ,Environmental Engineering ,Denitrification ,Nitrogen ,030106 microbiology ,Sequencing batch reactor ,010501 environmental sciences ,01 natural sciences ,Nitrogen removal ,Water Purification ,03 medical and health sciences ,Denitrifying bacteria ,chemistry.chemical_compound ,Bioreactors ,Nitrate ,Carbon source ,Dietary Nitrate ,Nitrites ,0105 earth and related environmental sciences ,Biological Oxygen Demand Analysis ,Nitrates ,Chemistry ,General Medicine ,Paracoccus ,Pulp and paper industry ,Aerobiosis ,Carbon ,Aeration - Abstract
Effects of operational parameters (initial nitrite concentration, initial nitrate concentration, carbon source, and COD/N ratio) on denitrification performance was evaluated using a sequencing batch reactor (SBR) under intermittent aeration. Complete denitrification was observed without N
- Published
- 2019
38. Mitochondrial nucleoid remodeling and biogenesis are regulated by the p53-p21
- Author
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Yun Yeong, Lee, Yeon Seung, Choi, Do Wan, Kim, Jae Youn, Cheong, Kye Yong, Song, Min Sook, Ryu, and In Kyoung, Lim
- Subjects
Cyclin-Dependent Kinase Inhibitor p21 ,senescence ,Protein Serine-Threonine Kinases ,DNA, Mitochondrial ,Oxidative Phosphorylation ,Mitochondrial Proteins ,nucleoid remodeling ,AMP-Activated Protein Kinase Kinases ,p53-p21-PKCζ activation ,Humans ,Topoisomerase II Inhibitors ,Gene Silencing ,Cellular Senescence ,Cyclin-Dependent Kinase Inhibitor p16 ,Protein Kinase C ,Organelle Biogenesis ,Nuclear Respiratory Factor 1 ,Fibroblasts ,Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha ,p16INK4a silence ,Mitochondria ,DNA-Binding Proteins ,mitochondria ,Doxorubicin ,Tumor Suppressor Protein p53 ,Signal Transduction ,Transcription Factors ,Research Paper - Abstract
Mitochondrial dysfunction is linked to age-related senescence phenotypes. We report here the pathway increasing nucleoid remodeling and biogenesis in mitochondria during the senescence of foreskin human diploid fibroblasts (fs-HDF) and WI-38 cells. Replicative senescence in fs-HDF cells increased mitochondrial nucleoid remodeling as indicated by 5-bromo-2'-deoxyuridine (BrdU) incorporation and mitochondrial transcription factor A (TFAM) expression in enlarged and fused mitochondria. Mitochondrial nucleoid remodeling was accompanied by mitochondrial biogenesis in old cells, and the expression levels of OXPHOS complex-I, -IV and -V subunits, PGC-1α and NRF1 were greatly increased compared to young cells. Activated protein kinase C zeta (PKCζ) increased mitochondrial activity and expressed phenotypes of delayed senescence in fs-HDF cells, but not in WI-38 cells. The findings were reproduced in the doxorubicin-induced senescence of young fs-HDF and WI-38 cells via the PKCζ-LKB1-AMPK signaling pathway, which was regulated by the p53-p21WAF1 pathway when p16INK4a was silenced. The signaling enhanced PGC-1α-NRF1-TFAM axis in mitochondria, which was demonstrated by Ingenuity Pathway Analysis of young and old fs-HDF cells. Activation of the p53-p21WAF1 pathway and silencing of p16INK4a are responsible for mitochondrial reprogramming in senescent cells, which may be a compensatory mechanism to promote cell survival under senescence stress.
- Published
- 2019
39. Emission characteristics of particulate matter, odors, and volatile organic compounds from the grilling of pork
- Author
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Kyung-Won Park, Jun Min Jeon, Yun Yeong Lee, Jeonghee Yun, Sang Beom Han, Kyung Suk Cho, Kyung Chel Oh, Yoonjoo Seo, Jihyun Kwon, and Hyungjoo Park
- Subjects
Ozone ,Swine ,010501 environmental sciences ,01 natural sciences ,Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Vinyl acetate ,Animals ,030212 general & internal medicine ,Benzene ,0105 earth and related environmental sciences ,General Environmental Science ,Air Pollutants ,Volatile Organic Compounds ,Acetaldehyde ,Butane ,Particulates ,Red Meat ,chemistry ,Odor ,Hexene ,Environmental chemistry ,Odorants ,Environmental science ,Particulate Matter ,Environmental Monitoring - Abstract
Meat-grilling restaurants are considered to be residential emission sources of air pollutants. To investigate the emission characteristics of particulate matter (PM), odors, and volatile organic compounds (VOCs) from the grilling of meat, a grilling apparatus equipped with butane gas burners was used to grill pork belly and marinated pork ribs in a laboratory setting. When grilling the pork belly, the emission factor for PM with a diameter of 2.5 μm or below (PM2.5) was 754 mg-PM·kg-meat−1, accounting for 99% of total suspended particles (TSPs), while that of the marinated pork ribs was 137 mg-PM·kg-meat−1 (96% of TSPs). Ammonia and acetaldehyde were the most common odors emitted during grilling at 43–88 mg·kg-meat−1 and 22–30 mg·kg-meat−1, respectively. Aldehydes were the most significant contributor to total odor intensity (36%–67%). Benzene, vinyl acetate, and hexene were the most abundant VOCs for the pork belly, while butane, vinyl acetate, and n-dodecane were the most abundant for the marinated ribs. Among the VOCs emitted from the pork grilling process, hexene, butane, and toluene were the dominant ozone precursors. The information obtained in this study is useful for furthering the understanding of the characteristics of air pollutants emitted from actual meat-grilling restaurants. Additionally, knowledge of the PM, odor, and VOC emission characteristics and their emission factors is useful for establishing management strategies for air pollutants from meat-grilling restaurants.
- Published
- 2019
40. Design and shelf stability assessment of bacterial agents for simultaneous removal of methane and odors
- Author
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Yun Yeong Lee, Kyung Suk Cho, and Sodaneath Hong
- Subjects
0106 biological sciences ,Environmental Engineering ,food.ingredient ,Lysobacter ,010501 environmental sciences ,Sulfides ,01 natural sciences ,Methane ,chemistry.chemical_compound ,Soil ,food ,Paracoccus ,010608 biotechnology ,Promicromonospora ,Soil Microbiology ,0105 earth and related environmental sciences ,biology ,Bacteria ,Microbiota ,General Medicine ,biology.organism_classification ,Sphingopyxis ,Biodegradation, Environmental ,chemistry ,Odor ,Environmental chemistry ,Odorants ,Dimethyl sulfide - Abstract
Two types of solid bacterial agents for the simultaneous removal of methane and odor were designed using humic soil (De-MO-1) and the mixture of humic soil and tobermolite (De-MO-2) as biocarriers. The bacterial consortium, having the removability of methane and dimethyl sulfide (DMS), was immobilized in the biocarriers, and then stored at room temperature for 375 days without additional treatment. Although the lag period, of which the incubation time required for removing methane and DMS, tended to increase over the storage period, the removability of methane and DMS was maintained during 375 days in both bacterial agents. Key bacteria associated with the removal of methane and odors (Streptomyces, Promicromonospora, Paracoccus, Lysobacter, Sphingopyxis and Methylosystis) could keep their abundance during the storage period. The richness and evenness values of the bacterial communities in De-MO-1 and De-MO-2 ranged 4.89 ∼ 6.50 and 0.89 ∼ 0.98, respectively, indicating that high bacterial diversity was maintained during the storage period. The results suggest that De-MO-1 and De-MO-2, designed for the simultaneous removal of methane and odors, had shelf stabilities over one year.
- Published
- 2019
- Full Text
- View/download PDF
41. Evaluation of rhizoremediation and methane emission in diesel-contaminated soil cultivated with tall fescue (Festuca arundinacea)
- Author
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Kyung Suk Cho, Yun Yeong Lee, Hyoju Yang, Jiho Lee, Yoonjoo Seo, and Minyoung Ha
- Subjects
Festuca ,Amendment ,010501 environmental sciences ,engineering.material ,01 natural sciences ,Biochemistry ,Soil ,03 medical and health sciences ,Diesel fuel ,0302 clinical medicine ,Soil Pollutants ,030212 general & internal medicine ,Polycyclic Aromatic Hydrocarbons ,Soil Microbiology ,0105 earth and related environmental sciences ,General Environmental Science ,biology ,Compost ,Sowing ,biology.organism_classification ,Soil contamination ,Biodegradation, Environmental ,Agronomy ,Soil water ,engineering ,Environmental science ,Rhizobium ,Methane ,Festuca arundinacea - Abstract
Rhizoremediation, CH4 emission, and bacterial community dynamics were evaluated in diesel-contaminated soil cultivated with tall fescue via a pot experiment. At the beginning of the experiment, total petroleum hydrocarbons (TPHs) removal efficiency was 30.2% in tall fescue-cultivated soil, which was significantly higher than that of unplanted soil (19.4%). However, when compost was added as a soil amendment, TPHs removal efficiency increased to 39.2% in tall fescue-cultivated soil. Interestingly, potential CH4 emissions were more affected by the initial diesel concentration than by compost addition or tall fescue planting. Specifically, the potential CH4 emission was approximately 3.8 times higher in the treatment with the highest initial diesel concentration (T-WC38) than that of the treatment with the lowest initial diesel concentration (T-WC5). Functional gene analysis revealed that TPHs removal had a linear correlation with the alkB/16S gene ratio, whereas potential CH4 emission had a linear correlation with pmoA gene copy numbers. Initial diesel concentrations in soil also affected bacterial community structures and the genera Rhizobium, Halothiobacillus, and Geobacter were found to be positively linked to diesel-contaminated soil rhizoremediation. Therefore, this study provides useful insights into the development of strategies to enhance rhizoremediation efficiency and CH4 emission mitigation in diesel-contaminated soils.
- Published
- 2021
42. A ‘Geological’ cinematic space and the problem of the divinity in Tarkovsky’s the Stalker
- Author
-
Yun-yeong Lee
- Subjects
Divinity ,media_common.quotation_subject ,Art history ,Art ,Space (commercial competition) ,media_common - Published
- 2016
43. Process contribution evaluation for COD removal and energy production from molasses wastewater in a BioH2–BioCH4–MFC-integrated system
- Author
-
Kyung Suk Cho, Yun Yeong Lee, Hyung Joo Choi, and Jeonghee Yun
- Subjects
Energy recovery ,Microbial fuel cell ,Waste management ,Hydraulic retention time ,020209 energy ,Chemical oxygen demand ,Bioengineering ,02 engineering and technology ,General Medicine ,010501 environmental sciences ,01 natural sciences ,Volume (thermodynamics) ,Wastewater ,0202 electrical engineering, electronic engineering, information engineering ,Environmental science ,Industrial and production engineering ,Effluent ,0105 earth and related environmental sciences ,Biotechnology - Abstract
In this study, a three-stage-integrated process using the hydrogenic process (BioH2), methanogenic process (BioCH4), and a microbial fuel cell (MFC) was operated using molasses wastewater. The contribution of individual processes to chemical oxygen demand (COD) removal and energy production was evaluated. The three-stage integration system was operated at molasses of 20 g-COD L−1, and each process achieved hydrogen production rate of 1.1 ± 0.24 L-H2 L−1 day−1, methane production rate of 311 ± 18.94 mL-CH4 L−1 day−1, and production rate per electrode surface area of 10.8 ± 1.4 g m−2 day−1. The three-stage integration system generated energy production of 32.32 kJ g-COD−1 and achieved COD removal of 98 %. The contribution of BioH2, BioCH4, and the MFC reactor was 20.8, 72.2, and, 7.0 % of the total COD removal, and 18.7, 81.2, and 0.16 % of the total energy production, respectively. The continuous stirred-tank reactor BioH2 at HRT of 1 day, up-flow anaerobic sludge blanket BioCH4 at HRT of 2 days, and MFC reactor at HRT of 3 days were decided in 1:2:3 ratios of working volume under hydraulic retention time consideration. This integration system can be applied to various configurations depending on target wastewater inputs, and it is expected to enhance energy recovery and reduce environmental impact of the final effluent.
- Published
- 2016
44. Characterization of the COD removal, electricity generation, and bacterial communities in microbial fuel cells treating molasses wastewater
- Author
-
Kyung Suk Cho, Yun-Yeong Lee, and Tae G. Kim
- Subjects
0106 biological sciences ,Environmental Engineering ,Microbial fuel cell ,Bioelectric Energy Sources ,Proton exchange membrane fuel cell ,Wastewater ,010501 environmental sciences ,Waste Disposal, Fluid ,01 natural sciences ,Electricity ,010608 biotechnology ,Proteobacteria ,Bioreactor ,Molasses ,Biomass ,0105 earth and related environmental sciences ,Biological Oxygen Demand Analysis ,Waste management ,Methanobacterium ,Chemical oxygen demand ,Methanosarcinaceae ,General Medicine ,Biodegradation ,Electricity generation ,Methanosarcina ,Environmental science ,Sewage treatment - Abstract
The chemical oxygen demand (COD) removal, electricity generation, and microbial communities were compared in 3 types of microbial fuel cells (MFCs) treating molasses wastewater. Single-chamber MFCs without and with a proton exchange membrane (PEM), and double-chamber MFC were constructed. A total of 10,000 mg L(-1) COD of molasses wastewater was continuously fed. The COD removal, electricity generation, and microbial communities in the two types of single-chamber MFCs were similar, indicating that the PEM did not enhance the reactor performance. The COD removal in the single-chamber MFCs (89-90%) was higher than that in the double-chamber MFC (50%). However, electricity generation in the double-chamber MFC was higher than that in the single-chamber MFCs. The current density (80 mA m(-2)) and power density (17 mW m(-2)) in the double-chamber MFC were 1.4- and 2.2-times higher than those in the single-chamber MFCs, respectively. The bacterial community structures in single- and double-chamber MFCs were also distinguishable. The amount of Proteobacteria in the double-chamber MFC was 2-3 times higher than those in the single-chamber MFCs. For the archaeal community, Methanothrix (96.4%) was remarkably dominant in the single-chamber MFCs, but Methanobacterium (35.1%), Methanosarcina (28.3%), and Methanothrix (16.2%) were abundant in the double-chamber MFC.
- Published
- 2016
45. Regulations of Reversal of Senescence by PKC Isozymes in Response to 12-O-Tetradecanoylphorbol-13-Acetate via Nuclear Translocation of pErk1/2
- Author
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Yun Yeong Lee, Min Sook Ryu, Masami Suganuma, Kye Yong Song, In Kyoung Lim, and Hong Seok Kim
- Subjects
0301 basic medicine ,Senescence ,Protein Kinase C-alpha ,MAP Kinase Signaling System ,HDF ,PKCβ1 ,Biology ,12-O-Tetradecanoylphorbol-13-acetate ,Article ,03 medical and health sciences ,chemistry.chemical_compound ,Mice ,Protein Kinase C beta ,Animals ,Humans ,Kinase activity ,Phosphorylation ,Protein kinase A ,Molecular Biology ,Protein kinase C ,Cellular Senescence ,Cell Proliferation ,Genetics ,SA-pErk1/2 ,integumentary system ,PKCα ,tumor promotion ,Cell Biology ,General Medicine ,Fibroblasts ,Cell biology ,Protein Transport ,030104 developmental biology ,chemistry ,Gene Expression Regulation ,Tetradecanoylphorbol Acetate ,Hair follicle cell proliferation ,Cell aging - Abstract
The mechanism by which 12-O-tetradecanoylphorbol-13-acetate (TPA) bypasses cellular senescence was investigated using human diploid fibroblast (HDF) cell replicative senescence as a model. Upon TPA treatment, protein kinase C (PKC) α and PKCβ1 exerted differential effects on the nuclear translocation of cytoplasmic pErk1/2, a protein which maintains senescence. PKCα accompanied pErk1/2 to the nucleus after freeing it from PEA-15pS(104) via PKCβ1 and then was rapidly ubiquitinated and degraded within the nucleus. Mitogen-activated protein kinase docking motif and kinase activity of PKCα were both required for pErk1/2 transport to the nucleus. Repetitive exposure of mouse skin to TPA downregulated PKCα expression and increased epidermal and hair follicle cell proliferation. Thus, PKCα downregulation is accompanied by in vivo cell proliferation, as evidenced in 7, 12-dimethylbenz(a)anthracene (DMBA)-TPA-mediated carcinogenesis. The ability of TPA to reverse senescence was further demonstrated in old HDF cells using RNA-sequencing analyses in which TPA-induced nuclear PKCα degradation freed nuclear pErk1/2 to induce cell proliferation and facilitated the recovery of mitochondrial energy metabolism. Our data indicate that TPA-induced senescence reversal and carcinogenesis promotion share the same molecular pathway. Loss of PKCα expression following TPA treatment reduces pErk1/2-activated SP1 biding to the p21(WAF1) gene promoter, thus preventing senescence onset and overcoming G1/S cell cycle arrest in senescent cells.
- Published
- 2016
46. A Painting Sculpted in Time: The Adoration of the Magi in Tarkovsky's The Sacrifice
- Author
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이윤영 ( Yun Yeong Lee )
- Subjects
General Engineering - Abstract
안드레이 타르코프스키 감독의 영화 (1986)에서는 레오나르도다빈치의 회화 (1481)가 핵심적인 역할을 수행한다. 이 그림은 한편으로는 (문학적 각색과 다른) 회화적 각색의 대상으로서이 영화의 진정한 기원으로 기능하며, 다른 한편으로는 영화 진행 도중에지속적으로 인용되고 환기됨으로써 풍요로운 상호텍스트적 기능을 수행한다. 이 영화의 타이틀 시퀀스에서 강렬한 존재감을 드러내는 다빈치의이 그림은, 실제로 시나리오 쓰기를 포함한 이 영화의 구상 단계에서 핵심적인 역할을 했다. 사실상 의 배경들, 인물들, 주제 등은 이그림의 그것들과 긴밀한 관계를 갖고 있기 때문에, 심도 깊은 비교연구의대상이 될 수 있다. 나아가 이 그림은, 타이틀 시퀀스 이외에도 이 영화의진행 과정에서 4번에 걸친 인서트의 형태로 환기되고 인용되는데, 이때마다 그림 속에 들어 있는 서로 다른 층위들(인물, 배경, 주제 등)이 풍요롭게 환기되면서 영화의 그것들과 적극적으로 호응을 이룬다. 에서 를 대상으로 이루어진 타르코프스키 감독의 작업은 문학적 각색과 구별되는 회화적 각색의 길을 열고 있으며, 나아가풍요로운 상호텍스트적 작업의 예가 된다. 타르코프스키 감독의 작업은 결국 다빈치가 규정한 것처럼 ‘정신적인 것’으로서의 회화를 계승한다. 시/서/화의 일체를 표방한 한국의 문인화 전통은 ‘정신적인 것’으로서 회화를 구현하고 있기 때문에 타르코프스키의 작업과 같은 회화적 각색 및 적극적인 상호텍스트적 작업의 대상이 될 수 있다.
- Published
- 2015
47. Effect of upflow and downflow baffle configuration on particulate matter removal in a mirror-symmetrical multi-compartment scrubber.
- Author
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Kyung-Suk Cho, Soo-Kyung Kang, Yun-Yeong Lee, Soo Yeon Lee, and Insook Lee
- Subjects
PARTICULATE matter ,PRESSURE drop (Fluid dynamics) ,EMISSION control ,AIR quality - Abstract
Control over particulate matter (PM) emission from grilling is required for improving public health and air quality. The performance of mirror-symmetrical multi-compartment scrubbers with an upflow (U-type) and downflow baffle (D-type) configuration was evaluated for PM emission control from grilling at a flow rate of 30m3 min
-1 . The PM removal efficiency of the U-type scrubber was the highest when the water level was 8 cm (95.6%), and the pressure drops recorded at the water levels of 6, 8 and 10 cm were 103, 122 and 153 mmH2 O, respectively. Although PM removal efficiency of the D-type scrubber was over 91.0% at the water levels of 8, 10 and 12 cm, the pressure drops were 124, 142 and 185 mmH2 O, respectively. A comprehensive evaluation of the water volume, pressure drop and PM removal performance, as well as device size, revealed that the U-type scrubber with a PM removal efficiency of 92% or higher and a pressure drop of 122 mmH2 O or lower at the water levels of 6-8 cm was more economical for removing PM from grilling gas than the D-type scrubber. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
48. Effects of carbon source, C/N ratio, nitrate, temperature, and pH on N
- Author
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Yun-Yeong, Lee, Hyungjoo, Choi, and Kyung-Suk, Cho
- Subjects
Bioreactors ,Nitrates ,Genes, Bacterial ,Nitrogen ,Denitrification ,Nitrous Oxide ,Temperature ,Heterotrophic Processes ,Hydrogen-Ion Concentration ,Wastewater ,Carbon ,Water Purification - Abstract
The effects of operational parameters such as carbon source, C/N ratio, initial nitrate concentration, temperature, and pH value on heterotrophic denitrification and functional denitrifying genes were evaluated. When methanol was used as the sole carbon source, complete denitrification was performed in a short time without nitrous oxide (N
- Published
- 2018
49. Downregulated UCHL1 Accelerates Gentamicin-Induced Auditory Cell Death via Autophagy
- Author
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Yun Yeong Lee, Yeonju Kim, Oak-Sung Choo, Kyung Kim, Yun-Hoon Choung, and Jeong Hun Jang
- Subjects
0301 basic medicine ,Programmed cell death ,Neuroscience (miscellaneous) ,Down-Regulation ,Biology ,Efferent nerve ,Cell Line ,Rats, Sprague-Dawley ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Ototoxicity ,Downregulation and upregulation ,Hair Cells, Auditory ,Protein Interaction Mapping ,Sequestosome-1 Protein ,medicine ,Autophagy ,Animals ,Humans ,Spiral ganglion ,Cochlea ,beta Catenin ,Gene Expression Profiling ,Aminoglycoside ,Autophagosomes ,medicine.disease ,Cell biology ,Up-Regulation ,030104 developmental biology ,medicine.anatomical_structure ,Neurology ,Gentamicins ,Ubiquitin Thiolesterase ,030217 neurology & neurosurgery - Abstract
The clinical use of aminoglycoside antibiotics is partly limited by their ototoxicity. The pathogenesis of aminoglycoside-induced ototoxicity still remains unknown. Here, RNA-sequencing was conducted to identify differentially expressed genes in rat cochlear organotypic cultures treated with gentamicin (GM), and 232 and 43 genes were commonly up- and downregulated, respectively, at day 1 and 2 after exposure. Ubiquitin carboxyl-terminal hydrolase isozyme L1 (Uchl1) was one of the downregulated genes whose expression was prominent in spiral ganglion cells (SGCs), lateral walls, as well as efferent nerve terminal and nerve fibers. We further investigated if a deficit of Uchl1 in organotypic cochlea and the House Ear Institute-Organ of Corti 1 (HEI-OC1) cells accelerates ototoxicity. We found that a deficit in Uchl1 accelerated GM-induced ototoxicity by showing a decreased number of SGCs and nerve fibers in organotypic cochlear cultures and HEI-OC1 cells. Furthermore, Uchl1-depleted HEI-OC1 cells revealed an increased number of autophagosomes accompanied by decreased lysosomal fusion. These data indicate that the downregulation of Uchl1 following GM treatment is deleterious to auditory cell survival, which results from the impaired autophagic flux. Our results provide evidence that UCHL1-dependent autophagic flux may have a potential as an otoprotective target for the treatment of GM-induced auditory cell death.
- Published
- 2018
50. Effects of proton exchange membrane on the performance and microbial community composition of air-cathode microbial fuel cells
- Author
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Yun Yeong Lee, Kyung Suk Cho, and Tae Gwan Kim
- Subjects
Time Factors ,Microbial fuel cell ,Bioelectric Energy Sources ,Proton exchange membrane fuel cell ,Bioengineering ,Applied Microbiology and Biotechnology ,Organic compound ,Exoelectrogen ,Electricity ,Electrodes ,Biological Oxygen Demand Analysis ,chemistry.chemical_classification ,Bacteria ,biology ,Air ,Chemical oxygen demand ,Membranes, Artificial ,General Medicine ,biology.organism_classification ,Membrane ,chemistry ,Chemical engineering ,Biofilms ,Protons ,Geobacter ,Faraday efficiency ,Biotechnology - Abstract
This study investigated the effects of proton exchange membranes (PEMs) on performance and microbial community of air-cathode microbial fuel cells (MFCs). Air-cathode MFCs with reactor volume of 1L were constructed in duplicate with or without PEM (designated as ACM-MFC and AC-MFC, respectively) and fed with a mixture of glucose and acetate (1:1, w:w). The maximum power density and coulombic efficiency did not differ between MFCs in the absence or presence of a PEM. However, PEM use adversely affected maximum voltage production and the rate of organic compound removal (p0.05). Quantitative droplet digital PCR indicated that AC-MFCs had a greater bacterial population than ACM-MFCs (p0.05). Likewise, ribosomal tag pyrosequencing revealed that the diversity index of bacterial communities was greater for AC-MFCs (p0.05). Network analysis revealed that the most abundant genus was Enterococcus, which comprised ≥62% of the community and was positively associated with PEM and negatively associated with the rate of chemical oxygen demand (COD) removal (Pearson correlation0.9 and p0.05). Geobacter, which is known as an exoelectrogen, was positively associated with maximum power density and negatively associated with PEM. Thus, these results suggest that the absence of PEM favored the growth of Geobacter, a key player for electricity generation in MFC systems. Taken together, these findings demonstrate that MFC systems without PEM are more efficient with respect to power production and COD removal as well as exoelectrogen growth.
- Published
- 2015
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