• Biomolecules & Therapeutics
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• 제30권3호
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• pp.291-297
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• 2022

Dry age-related macular degeneration (AMD) is a type of progressive blindness that is primarily due to dysfunction and the loss of retinal pigment epithelium (RPE). The accumulation of N-retinylidene-N-retinylethanolamine (A2E), a by-product of the visual cycle, causes RPE and photoreceptor degeneration that impairs vision. Genes associated with dry AMD have been identified using a blue light model of A2E accumulation in the retinal pigment epithelium and transcriptomic studies of retinal tissue from patients with AMD. However, dry macular degeneration progresses slowly, and current approaches cannot reveal changes in gene transcription according to stages of AMD progression. Thus, they are limited in terms of identifying genes responsible for pathogenesis. Here, we created a model of long-term exposure to identify temporally-dependent changes in gene expression induced in human retinal pigment epithelial cells (ARPE-19) exposed to blue light and a non-cytotoxic dose of A2E for 120 days. We identified stage-specific genes at 40, 100, and 120 days, respectively. The expression of genes corresponding to epithelial-mesenchymal transition (EMT) during the early stage, glycolysis and angiogenesis during the middle stage, and apoptosis and inflammation pathways during the late stage was significantly altered by A2E and blue light. Changes in the expression of genes at the late stages of the EMT were similar to those found in human eyes with late-stage AMD. Our results provide further insight into the pathogenesis of dry AMD induced by blue light and a novel model in vitro with which relevant genes can be identified in the future.

• Molecules and Cells
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• 제43권7호
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• pp.632-644
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• 2020

The molecular mechanism underlying autophagy impairment in the retinal pigment epithelium (RPE) in dry age-related macular degeneration (AMD) is not yet clear. Based on the causative role of poly(ADP-ribose) polymerase 1 (PARP1) in RPE necrosis, this study examined whether PARP1 is involved in the autophagy impairment observed during dry AMD pathogenesis. We found that autophagy was downregulated following H₂O₂-induced PARP1 activation in ARPE-19 cells and olaparib, PARP1 inhibitor, preserved the autophagy process upon H₂O₂ exposure in ARPE-19 cells. These findings imply that PARP1 participates in the autophagy impairment upon oxidative stress in ARPE-19 cells. Furthermore, PARP1 inhibited autolysosome formation but did not affect autophagosome formation in H₂O₂-exposed ARPE-19 cells, demonstrating that PARP1 is responsible for impairment of late-stage autophagy in particular. Because PARP1 consumes NAD⁺ while exerting its catalytic activity, we investigated whether PARP1 impedes autophagy mediated by sirtuin1 (SIRT1), which uses NAD⁺ as its cofactor. A NAD⁺ precursor restored autophagy and protected mitochondria in ARPE-19 cells by preserving SIRT1 activity upon H₂O₂. Moreover, olaparib failed to restore autophagy in SIRT1-depleted ARPE-19 cells, indicating that PARP1 inhibits autophagy through SIRT1 inhibition. Next, we further examined whether PARP1-induced autophagy impairment occurs in the retinas of dry AMD model mice. Histological analyses revealed that olaparib treatment protected mouse retinas against sodium iodate (SI) insult, but not in retinas cotreated with SI and wortmannin, an autophagy inhibitor. Collectively, our data demonstrate that PARP1-dependent inhibition of SIRT1 activity impedes autophagic survival of RPE cells, leading to retinal degeneration during dry AMD pathogenesis.

• 한국지하수토양환경학회지:지하수토양환경
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• 제19권3호
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• pp.142-152
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• 2014

In this study, generic characteristics of the acid mine drainage (AMD), removal efficiency of iron, aluminium and manganese by chemical treatment, electrolysis and hybrid process using electrolysis after neutralization were evaluated. The pH of AMD was inversely proportional to the rainfall. In dry-season, the average pH of AMD was ranged from 4.5 to 5.5, showing slight variation. However, the pH of AMD was gradually decreased along with rainfall and dropped to 3.02 in September showing the greatest rainfall. Removal efficiency of heavy metals by chemical treatments using three different neutralizing agents or by electrolysis was low. However, a hybrid process performed with electrolysis after addition of neutralization shows higher removal capacity for heavy metal ions than neutralization-alone and electrolysisalone process.

• 대한지하수환경학회지
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• 제2권1호
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• pp.38-47
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• 1995

이 연구에서는 삼척탄전 내에 위치하는 폐탄광인 동해탄광을 대상으로 산성 광산폐수의 중화 처리를 위한 각종 기초자료를 제시하고자 하였다. 산성 광산폐수의 측정시기에 따른 변화양상을 관찰한 결과 갈 수기에는 각종 잠재적 유독성 원소들의 함량이 증가하며, pH가 하락하여 수질이 악화되는 경향을 보였다. 공업용 소석회는 처리효율 및 경제성을 고려할 경우 산성 광산폐수의 처리를 위한 최적의 중화제로 판단되며, 평형 모델링 결과 중화처리과정에서 Fe는 FeOOH의 형태로, Al은 Al(OH)$_3$, 의 형태로 침전되는 것으로 추정된다. GIS를 이용하여 동해탄광일대 산성 광산폐수 처리시설의 위치를 제시하였으며 수문학적 자료를 이용하여 최대강우량 및 첨두유량을 계산하였다.

• Journal of Ginseng Research
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• 제47권1호
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• pp.65-73
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• 2023

Background: Age-related macular degeneration (AMD) is a significant visual disease that induces impaired vision and irreversible blindness in the elderly. However, the effects of ginseng berry extract (GBE) on the retina have not been studied. Therefore, this study aimed to investigate the protective effects of GBE on blue light (BL)-induced retinal damage and elucidate its underlying mechanisms in human retinal pigment epithelial cells (ARPE-19 cells) and Balb/c retina. Methods: To investigate the effects and underlying mechanisms of GBE on retinal damage in vitro, we performed cell viability assay, pre-and post-treatment of sample, reactive oxygen species (ROS) assay, quantitative real-time PCR (qRT-PCR), and western immunoblotting using A2E-laden ARPE-19 cells with BL exposure. In addition, Balb/c mice were irradiated with BL to induce retinal degeneration and orally administrated with GBE (50, 100, 200 mg/kg). Using the harvested retina, we performed histological analysis (thickness of retinal layers), qRT-PCR, and western immunoblotting to elucidate the effects and mechanisms of GBE against retinal damage in vivo. Results: GBE significantly inhibited BL-induced cell damage in ARPE-19 cells by activating the SIRT1/PGC-1α pathway, regulating NF-kB translocation, caspase 3 activation, PARP cleavage, expressions of apoptosis-related factors (BAX/BCL-2, LC3-II, and p62), and ROS production. Furthermore, GBE prevented BL-induced retinal degeneration by restoring the thickness of retinal layers and suppressed inflammation and apoptosis via regulation of NF-kB and SIRT1/PGC-1α pathway, cleavage of caspase 3 and PARP, and expressions of apoptosis-related factors in vivo. Conclusions: GBE could be a potential agent to prevent dry AMD and progression to wet AMD.

• 자원환경지질
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• 제31권6호
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• pp.499-508
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• 1998

The Imgok Creek is located in the Gangreung coal field, which has been known that sulfides are more abundant than other coal fields in Korea, and it has been severly contaminated by acid mine drainage (AMD) discharging from the abandoned coal mines, such as the Youngdong, the Dongduk and the Waryong coal mines. The purposes of this study are to synthetically assess the contamination of natural water, stream sediment and cultivated soils, and to provide the basic data for AMD treatment. Geochemical samples were collected in December, 1996 (dry season) and April, 1997 (after three day's rainfall). TDS of the Youngdong mine water was remarkably higher than those of other mine waters. In the Imgok Creek, concentrations of most elements, except Fe decreased with distance by dilution caused by the inflow of uncontaminated tributaries. From the results of NAMDI and $I_{geo}$ calculation, the Youngdong coal mine was the main contamination source of the study area. Groundwater pollution was not yet confirmed in this study and the paddy and farm land soils were also not yet contaminated by mining activity based on the pollution index ranging from 0.27 to 0.47.

• 한국재료학회지
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• 제7권12호
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• pp.1070-1076
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• 1997

DLC(diamond-like carbon)박막을 RF PCVD법으로 증착하여 일반적인 증착특성과 마찰.마모특성사이의 관계를 알아보기 위해, 증착속도, 박막경도, 내무압축응력 및 박막내의 수소량 측정을 통해 일반적인 증착특성을 조사하였다. 그리고 증착된 박막의 C-H 결합구조와 물질특성 분성을 위해 각각 FTIR 및 Raman분광분석을 행하였다. 박막의 마찰계수와 내마모특성은 Pin-on-disk형 마찰시험기를 이용하여 상기의 증착조건과의 상관관계를 조사하였다. DC self-bais, 즉 충돌에너지가 커지면 박막의 증착속도와 경도는 대체로 증가하고, 박막내의 압축응력은 최대값을 가지다가 다시 감소됨을 알 수 있언ㅆ다. 또한 박막내의 수소량은 급격히 감소하다가 포화됨을 알 수 있었다. 얻어진 박막의 마찰계수는 최소 0.08로 분위기가 dry일 때 더 작으며 내마모성은 이온의 충돌에너지와 밀접한 관계를 가지며 모재인 Si-wafer보다 훨씬 큼을 알수 있었다.

• 한국수산과학회지
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• 제49권3호
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• pp.385-392
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• 2016

Seasonal variability in the algal community structure of intertidal zones was examined at six study sites in Marine National Parks, on the western and southern coasts of Korea from March to November 2015. A total of 193 species of algae, comprising 27 green, 40 brown and 126 red algae, were identified. Algal biomass averaged 101.50 g dry wt./m² with a maximal at Tonggae (168.12 g dry wt./m²) and minimum at Haseom (54.49 g dry wt./m²). The dominant seaweeds by biomass were Sargassum thunbergii at five sites (Tonggae, Haseom, Namdongri, Ando amd Sinjeonri), and S. fusiforme at Soando. Community indices measured as follows: dominance index (DI), 0.31–0.69; richness index (R), 7.30–11.43; evenness index (J'), 0.33–0.49; and diversity index (H'), 1.15–1.86. As evaluated using community indices and environmental states, the EEI (Ecological Evaluation Index) of the Marine National Park was “normal”. The present results indicate that seaweed community structures and indices could be used to evaluate the environmental status of coastal ecosystems.

• Clinical and Experimental Reproductive Medicine
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• 제37권2호
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• pp.89-98
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• 2010

성호르몬은 lacrimal system, corneal anatomy and disease, aqueous humor dynamics and glaucoma, crystalline lens and cataract, retinal disease를 포함한 안과영역의 다양한 부위에 영향을 끼칠 수 있다. Androgen은 전신에 걸친 sebaceous glands의 발달, 분화, 지질생성 등에 관여하므로 androgen deficiency는 meibomian gland의 기능장애와 건성안에서 증발을 더욱더 심화시킬 수 있는 것으로 알려져 있다. 반면에 estrogens은 sebaceous glands의 크기, activity, 지질생성을 감소시켜 meibomian gland에서는 androgen과 반대되는 작용을 할 가능성이 있다. 성호르몬은 또한 각막의 구조와 질병경과에도 영향을 줄 수 있는데, 각막이 월경주기 제2일째 및 배란주위기에 두꺼워지며, 폐경 여성에서 여성호르몬 치료 시 각막두께가 증가한다는 사실은 estrogen levels과 각막 두께와의 연관을 시사하는 소견이라고 하겠다. Fuch's dystrophy 역시 폐경 후 여성에서 더 흔히 관찰되어, 나이에 따른 호르몬 변화가 그 원인 중 하나로 지목되고 있으며, vernal keratoconjunctivitis 환자의 각막조직에서는 estrogen과 progesterone 수용체의 overexpresson이 발견되어 역시 이들 질환에서의 성호르몬의 역할을 시사한다고 할 수 있겠다. 성호르몬은 안압에도 영향을 미칠 수 있는데, intraocular pressure와 혈중 luteinizing hormone, follicular stimulating hormone (FSH), estrone, estradiol, progesterone, testosterone과는 연관이 없는 것으로 보고한 결과도 있으나, 혈중 progesterone의 경우 특히 임신중인 여성에서 안압과의 연관관계가 보고되었으며, 또한 폐경 여성에서 혈중 남성호르몬 농도가 높을수록 안압이 상승하는 경향이 있음이 보고되었다. 한편 'Female sex'는 모든 종류의 백내장의 위험요소인 것으로 알려져 있다. 백내장으로 진단받은 여성의 경우 호르몬 측정 시 연령등을 보정하고도 폐경기에 가까운 호르몬 수치를 보였으며, 이들 백내장 환자군내에서는 estradiol과 FSH 농도 사이에 유의한 음의 상관관계가 보고되었다. 또한 DHEAS의 경우 백내장 위험도를 감소시키는 것으로 보고되었고, 그 기전으로 전구호르몬인 DHEA의 역할을 제시되고 있는데. 즉 백내장의 주요 기전 중 하나인 oxidative stress를 감소시키는 antioxidant activity를 DHEA가 보이기 때문일 것으로 추정되고 있다. 성호르몬은 망막 내 혈관의 흐름에도 영향을 줄 수 있는 것으로 알려져 있는데, 안구 내 혈류에서 여성호르몬의 긍정적인 효과와 남성호르몬의 부정적인 효과가 보고되었고, age-related macular degeneration (AMD)의 경우, estradiol이 ER-$\beta$ 수용체를 통해 보호효과가 있음이 보고되어, ER-$\beta$ 수용체가 향후 AMD 치료에서 치료적 target이 될 수도 있을 것으로 알려지고 있다. 또한 DHEAS의 경우 AMD 위험도를 증가시킬 가능성이 있으며, 당뇨로 진단받은 환자에서는 혈중 testosterone 농도는 당뇨병성 망막병증의 진행과 연관이 있는 것으로 보고되었다. 성호르몬은 안과영역의 다양한 질환과의 연관관계는 아직 추가연구가 필요한 실정이나 다양한 성호르몬이 안질환의 발생 및 경과에 영향을 줄 가능성이 있으며, 이와 같은 연관관계가 규명된다면 추후 호르몬을 통해 질환의 경과 및 예방의 가능성이 제시될 수도 있을 것으로 사료된다. 특히 폐경이후 다양한 안질환이 증가한다는 기존의 연구결과들을 고려 시, 안과영역에 있어 폐경기 여성호르몬 치료의 긍정적인 역할에 관해서는 지속적인 관심이 요구된다고 하겠다.

• 자원환경지질
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• 제28권3호
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• pp.213-220
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• 1995

Geochemistry of stream water and sediment collected in the vicinity of the Donghae coal mine in the Samchuk coalfied were investigated in order to evaluate the environmental impacts of acid mine drainage. The pH of stream water ranges from 2.85(at 2 km away from the mine) to 7.92(at uncontaminated tributary). The main cation and anion species in the upper stream are $Ca^{2+}$ and $SO_{4}{^2-}$, respectively. The level of pH and the amount of $HCO^{3-}$ in stream water increase to the downstream and where uncontaminated small tributaries are joining, and in the area covered with limestone. From the results of thermodynamic calculation, the main forms of iron in stream water are estimated as $Fe^{2+}$ and $FeSO_{4}{^0}$, and most of them could be precipitated as FeO(OH) with increase of pH. The white precipitates in stream sediments particularly found around the coal mine are proved to be $Al(OH)_3$ by XRD and XRF analysis. As a result of investigation for seasonal variation of AMD, the level of pH decreased and conductivity increased in dry season.