المؤلفون: Lyle Babcock, Hui J. Wang, Joseph Recio, Amy D. Hanna, Susan L. Hamilton, Chang Seok Lee

المصدر: FASEB J

مصطلحات موضوعية: Male, 0301 basic medicine, Protein aggregation, medicine.disease_cause, Calsequestrin, Biochemistry, Article, Mice, 03 medical and health sciences, 0302 clinical medicine, Muscular Diseases, Genetics, medicine, Protein biosynthesis, Animals, Muscle, Skeletal, Myopathy, Molecular Biology, Mutation, Chemistry, Endoplasmic reticulum, Calcium-Binding Proteins, Endoplasmic Reticulum Stress, Cell biology, Lysosomal Storage Diseases, Sarcoplasmic Reticulum, 030104 developmental biology, Proteasome, Unfolded protein response, Calcium, medicine.symptom, 030217 neurology & neurosurgery, Biotechnology

الوصف: Mice with a mutation (D244G, DG) in calsequestrin 1 (CASQ1), analogous to a human mutation in CASQ1 associated with a delayed onset human myopathy (vacuolar aggregate myopathy), display a progressive myopathy characterized by decreased activity, decreased ability of fast twitch muscles to generate force and low body weight after one year of age. The DG mutation causes CASQ1 to partially dissociate from the junctional sarcoplasmic reticulum (SR) and accumulate in the endoplasmic reticulum (ER). Decreased junctional CASQ1 reduces SR Ca(2+) release. Muscles from older DG mice display ER stress, ER expansion, increased mTOR signaling, inadequate clearance of aggregated proteins by the proteasomes, and elevation of protein aggregates and lysosomes. This study suggests that the myopathy associated with the D244G mutation in CASQ1 is driven by CASQ1 mislocalization, reduced SR Ca(2+) release, CASQ1 misfolding/aggregation and ER stress. The subsequent maladaptive increase in protein synthesis and decreased protein aggregate clearance are likely to contribute to disease progression.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4ba44a3d5e2443c5411a90de272c22b9Test
https://doi.org/10.1096/fj.202001653rrTest

المؤلفون: A Reum Kim, Kye Han Lee, Jeong Suk Moon, Hyun Je Cho, Chang Seok Lee, Chi Hong Lim, Jeong Hoon Pi, Kee Dae Kim, Young Han You, Kyu Song Lee

المصدر: International Journal of Environmental Research and Public Health, Vol 18, Iss 1724, p 1724 (2021)
International Journal of Environmental Research and Public Health
Volume 18
Issue 4

مصطلحات موضوعية: 0106 biological sciences, restoration, Health, Toxicology and Mutagenesis, lcsh:Medicine, riparian vegetation, 010501 environmental sciences, 01 natural sciences, Article, Rivers, Water Quality, Aquatic plant, Republic of Korea, medicine, Animals, Restoration ecology, Ecosystem, 0105 earth and related environmental sciences, Riparian zone, Hydrology, geography, geography.geographical_feature_category, 010604 marine biology & hydrobiology, lcsh:R, Public Health, Environmental and Occupational Health, Species diversity, diagnostic evaluation, reference river information, Invertebrates, Habitat, river type, Environmental science, Water quality, medicine.symptom, Vegetation (pathology), Global biodiversity

الوصف: We assessed the naturalness of rivers based on the riparian vegetation index throughout the national territory of South Korea as a preparatory process for restoration to improve the ecological quality of rivers. The riparian vegetation index was obtained by incorporating the diversity of species and community, vegetation profile, and ratios of the number of species and areas occupied by exotic, obligate upland, and annual plants. The evaluation was conducted based on both the riparian vegetation index and each vegetation component. The result of the evaluation based on the riparian vegetation index showed that more than 70% of the river reaches were graded as less than “moderate” and exotic and obligate upland plants were more common than endemic aquatic plants. The reaches recorded as “very good” and “good” grades were usually restricted around the upstream of the north and central-eastern parts, whereas reaches of the other areas showed “poor” naturalness (less than “moderate”). The vegetation components selected for the evaluation showed a significant correlation with each other as well as the riparian vegetation index. The degree of contribution of each vegetation component showed that the vegetation profile played the most significant role, followed by species diversity, community diversity, and the ratio of area occupied by annual plants. The riparian vegetation index revealed a significant correlation with the indices based on other taxa such as benthic invertebrates, periphytic algae, and fish, habitat conditions in the waterway, and water quality based on biochemical oxygen demand (BOD). The diagnostic evaluation results imply that most reaches need ecological restoration. The reference information was prepared by incorporating the vegetation condition with the highest score in each reach in the diagnostic evaluation. The river reach was divided into five reaches of upper and lower valley streams, upstream, midstream, and downstream. Information on the reference vegetation for restoration was prepared with the stand profile including both horizontal and vertical arrangements of riparian vegetation and species composition classified by the reach divided into five types. The levels of restoration were determined based on the diagnostic evaluation results. The lower the naturalness grade, the higher the level of restorative treatment was recommended.

وصف الملف: application/pdf

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::5fcefe3cb2654de916786badccc015f5Test
https://www.mdpi.com/1660-4601/18/4/1724Test

المؤلفون: Eun-Soo Lee, Chang Seok Lee, Tae Ryong Lee, Yong Jin Kim, Dae Yong Kim, Jaeyoung Ko, Sung Hoon Lee, Jae Won Yoo, Il-Hong Bae

المصدر: Experimental Dermatology. 28:738-741

مصطلحات موضوعية: 0301 basic medicine, MAPK/ERK pathway, MAP Kinase Signaling System, Tyrosinase, Primary Cell Culture, Drug Evaluation, Preclinical, Human skin, Dermatology, Biochemistry, Cell Line, Melanin, Mice, 030207 dermatology & venereal diseases, 03 medical and health sciences, 0302 clinical medicine, Glycolipid, Hyperpigmentation, hemic and lymphatic diseases, medicine, Animals, Humans, Skin equivalent, neoplasms, Molecular Biology, Melanins, integumentary system, Chemistry, Microphthalmia-associated transcription factor, Cell biology, 030104 developmental biology, Melanocytes, Glycolipids, medicine.symptom

الوصف: Hyperpigmentation is caused by excessive production of melanin in melanocytes. Mannosylerythritol lipids (MELs) are glycolipid biosurfactants that are abundantly produced by yeasts and used commercially in cosmetics. However, the potential depigmenting efficacy of MELs has not been evaluated. In this study, the depigmentary effect of MELs was tested in primary normal human melanocytes (NHMs), α-melanocyte-stimulating hormone (MSH)-stimulated B16 cells (murine melanoma cells) and a human skin equivalent (MelanoDerm) using photography, Fontana-Masson (F&M) staining and two-photon microscopy. Mannosylerythritol lipids significantly decreased the melanin contents in NHMs and α-MSH-stimulated B16 cells. Consistent with these findings, MELs treatment had a clear whitening effect in a human skin equivalent, brightening the tissue colour and reducing the melanin content. The molecular mechanism underlying the anti-melanogenic effect of MELs treatment was examined by real-time PCR and Western blotting. Mechanistically, MELs clearly suppressed the gene expression levels of representative melanogenic enzymes, including tyrosinase, Tyrp-1 and Tyrp-2, by inhibiting the ERK/CREB/MiTF signalling pathway in NHMs. This work demonstrates for the first time that MELs exert whitening effects on human melanocytes and skin equivalent. Thus, we suggest that MELs could be developed as a potent anti-melanogenic agent for effective whitening, beyond their use as a biosurfactant in cosmetics.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::05d5e7c56841285978fc257c47f8d2edTest
https://doi.org/10.1111/exd.13836Test

المؤلفون: Sang Whan Han, Chang Seok Lee

المصدر: Engineering Structures. 173:892-907

مصطلحات موضوعية: Empirical equations, 021110 strategic, defence & security studies, business.industry, Computer science, 0211 other engineering and technologies, Stiffness, 020101 civil engineering, 02 engineering and technology, Structural engineering, Predictor variables, Reinforced concrete, Rc columns, 0201 civil engineering, Seismic analysis, Shear (geology), medicine, medicine.symptom, business, Reinforcement, Civil and Structural Engineering

الوصف: To evaluate the seismic performance of existing old reinforced concrete (RC) buildings, it is important to use an accurate analytical model. Most columns in these buildings do not satisfy the reinforcement details specified by current seismic design provisions. Columns that possess insufficient reinforcement details can exhibit significant pinching and cyclic deterioration in their strength and stiffness. They can also experience flexure-shear and shear failure during large earthquakes. The objective of this study is to simulate the cyclic behaviour of old RC columns accurately and efficiently with the Pinching4 model considering pinching and cyclic deterioration. Modelling parameters are calibrated based on the test results of 40 collected flexure-shear and shear critical columns. Columns failed by other failure modes rather than shear and flexure-shear failure are not considered in this study. Forward stepwise regression analyses are conducted to determine statistically significant variables from 34 candidate predictor variables and to propose the empirical equations of the modelling parameters. It is shown that the Pinching4 model with the proposed empirical equations accurately simulates the cyclic behaviour of both flexure-shear and shear-critical columns including pinching and cyclic deterioration in strength and stiffness.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::5adb9cafd3257d21dc2541a471f6a8a6Test
https://doi.org/10.1016/j.engstruct.2018.07.020Test

المؤلفون: Chang Seok Lee, Junseong Park, G.-B. Nam

المصدر: Clinical and Experimental Dermatology. 44:295-299

مصطلحات موضوعية: Sapogenins, Tyrosinase, Dermatology, Melanin, Mice, 030207 dermatology & venereal diseases, 03 medical and health sciences, chemistry.chemical_compound, Ginseng, 0302 clinical medicine, Cell Line, Tumor, medicine, Animals, Humans, Cyclic AMP Response Element-Binding Protein, Melanoma, Transcription factor, Melanins, Protopanaxatriol, Microphthalmia-Associated Transcription Factor, Membrane Glycoproteins, Dose-Response Relationship, Drug, integumentary system, Chemistry, Microphthalmia-associated transcription factor, Hyperpigmentation, Cell biology, Gene Expression Regulation, Neoplastic, Intramolecular Oxidoreductases, 030220 oncology & carcinogenesis, Drug Screening Assays, Antitumor, medicine.symptom, Oxidoreductases, Intracellular, Signal Transduction

الوصف: Ginsenosides are major active components of ginseng, and have diverse pharmacological properties in traditional medicine. Recent reports have shown that ginsenosides modify skin physiology and mitigate skin disorders such as photoageing and hyperpigmentation. We evaluated the antimelanogenic efficacy of protopanaxatriol, a major category of ginsenosides, as a depigmenting agent. Protopanaxatriol significantly reduced intracellular and extracellular melanin content in a concentration-dependent manner in B16 melanoma cells treated with α-melanocyte-stimulating hormone. In normal human epidermal melanocytes, protopanaxatriol clearly decreased melanin synthesis and dendrite elongation. In addition, protopanaxatriol dramatically suppressed the expression of genes encoding the melanogenic proteins tyrosinase, tyrosinase-related protein-1 and -2, and microphthalmia-associated transcription factor through dephosphorylation of cAMP response element-binding protein. These results suggest that protopanaxatriol could be an effective candidate anti-melanogenic agent.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::1806e528eb2fd1d055c863c389a350e8Test
https://doi.org/10.1111/ced.13734Test

المؤلفون: Yewon Park, Jong-Su Jeon, Chang Seok Lee

المصدر: Engineering Structures. 245:112820

مصطلحات موضوعية: Elastic net regularization, business.industry, Bent molecular geometry, Stiffness, Structural engineering, Plasticity, Moment (mathematics), Nonlinear system, Lasso (statistics), medicine, medicine.symptom, Envelope (mathematics), business, Civil and Structural Engineering, Mathematics

الوصف: This paper presents the model parameter estimation of a lumped plasticity model to realistically simulate the nonlinear load-deformation response of circular reinforced concrete columns under cyclic lateral loading. The model parameter calibration is based on an experimental database consisting of 210 circular columns with various input parameters, such as material strength, reinforcement layout, specimen geometry, and test configuration. The model parameter values for the initial stiffness, plastic rotation capacity, moment strength, and cyclic damage parameters are calibrated to the first-cycle envelope of each set of test data. Empirical predictive equations are developed to estimate the model parameters as functions of the input parameters using four different regression techniques: stepwise, ridge, lasso, and elastic net regression. The equations developed with lasso regression provided a reasonable trade-off between the prediction error and the number of input parameters. Important input parameters that affect the model parameters are the volumetric transverse reinforcement ratio, spacing of confinement steel, and axial load. As an application of the proposed column model, seismic fragilities of bridge columns in two bridge classes with different interior bent type are compared based on an existing distributed plasticity model and the proposed lumped plasticity model. The seismic vulnerability prediction discrepancy between the proposed and existing models tend to increase as the level of ground motion intensity increases. The prediction trend between the two models may differ by bent configuration and deck mass. The proposed column model reduces the seismic vulnerability of one-column bent bridge class, but increases the vulnerability of two-column bent bridge class.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::595e4f17c8a456bb054a21c8a07ab259Test
https://doi.org/10.1016/j.engstruct.2021.112820Test

المؤلفون: Chang Dae Heo, Sang Whan Han, Hyeyoung Koh, Chang Seok Lee

المصدر: Journal of the Earthquake Engineering Society of Korea. 21:303-310

مصطلحات موضوعية: Materials science, business.industry, Structural system, Stiffness, Structural engineering, Dissipation, Spring (device), Calibration, medicine, Physics::Accelerator Physics, Shear wall, medicine.symptom, Ductility, business, Beam (structure)

الوصف: The coupled shear wall system with coupling beams is an efficient structural system for high-rise buildings because it can provide excellent ductility and energy dissipation to the buildings. The objective of this study is to simulate the hysteretic behavior of diagonally reinforced concrete coupling beams including pinching and cyclic deteriorations in strength and stiffness using a numerical model. For this purpose, coupling beams are modeled with an elastic beam element and plastic spring element placed at the beam ends. Parameters for the analytical model was calibrated based on the test results of 6 specimens for diagonally reinforced concrete coupling beams. The analytical model with calibrated model parameters is verified by comparing the hysteretic curves obtained from analysis and experimental tests.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::516fb7acdcc70f9e9f3e3ec164363949Test
https://doi.org/10.5000/eesk.2017.21.6.303Test

المؤلفون: Corey L. Reynolds, Amy D. Hanna, Hui J. Wang, Yan Xia, George G. Rodney, Cheng Long, William R. Lagor, Keke Dong, Hisayuki Amano, Ergun Sahin, John C. Martin, Dimitra K. Georgiou, Mark Knoblauch, Aditya D. Joshi, Adan Dagnino-Acosta, Chang Seok Lee, Susan L. Hamilton, Jianjun Xu, Caroline Sewry

المصدر: Nature Communications, Vol 8, Iss 1, Pp 1-15 (2017)
Nature Communications

مصطلحات موضوعية: Male, 0301 basic medicine, Science, Muscle Proteins, General Physics and Astronomy, Apoptosis, Biology, Calsequestrin, Phenylbutyrate, Article, General Biochemistry, Genetics and Molecular Biology, 03 medical and health sciences, 0302 clinical medicine, medicine, Animals, Calcium Signaling, Muscle, Skeletal, Myopathy, RYR1, Multidisciplinary, Ryanodine receptor, Endoplasmic reticulum, Ryanodine Receptor Calcium Release Channel, General Chemistry, Endoplasmic Reticulum Stress, musculoskeletal system, Phenylbutyrates, Molecular biology, Mice, Mutant Strains, Mitochondria, 3. Good health, Cell biology, Mice, Inbred C57BL, Oxidative Stress, Phenotype, 030104 developmental biology, Triadin, Mutation, Unfolded protein response, Calcium, medicine.symptom, Carrier Proteins, Reactive Oxygen Species, tissues, 030217 neurology & neurosurgery, Signal Transduction

الوصف: Mutations in the RYR1 gene cause severe myopathies. Mice with an I4895T mutation in the type 1 ryanodine receptor/Ca2+ release channel (RyR1) display muscle weakness and atrophy, but the underlying mechanisms are unclear. Here we show that the I4895T mutation in RyR1 decreases the amplitude of the sarcoplasmic reticulum (SR) Ca2+ transient, resting cytosolic Ca2+ levels, muscle triadin content and calsequestrin (CSQ) localization to the junctional SR, and increases endoplasmic reticulum (ER) stress/unfolded protein response (UPR) and mitochondrial ROS production. Treatment of mice carrying the I4895T mutation with a chemical chaperone, sodium 4-phenylbutyrate (4PBA), reduces ER stress/UPR and improves muscle function, but does not restore SR Ca2+ transients in I4895T fibres to wild type levels, suggesting that decreased SR Ca2+ release is not the major driver of the myopathy. These findings suggest that 4PBA, an FDA-approved drug, has potential as a therapeutic intervention for RyR1 myopathies that are associated with ER stress.
Mutations in the RyR1 channel cause core myopathies. Here the authors show that ER stress and the unfolded protein response underlie the pathology caused by a common RyR1 channel mutation, and show that treatment with a chemical chaperone restores muscle function in mice.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::66e84c20b95dcf268f683054bd66cc5dTest
https://doaj.org/article/8a7faf752203416684267602ebe0758bTest

المؤلفون: Chang Seok Lee, Il-Hong Bae, Jeong Ah Hwang, Eun-Soo Lee, Dae Yong Kim, Seong Geun Oh, John Hwan Lee, Ho Sik Rho, Nok Hyun Park, Se Hwa Kim, Yong Jin Kim

المصدر: Skin Pharmacology and Physiology. 30:190-196

مصطلحات موضوعية: 0301 basic medicine, medicine.medical_specialty, Cell Survival, Physiology, Skin Lightening Preparations, Melanoma, Experimental, Human skin, Dermatology, Biology, Cell Line, Melanin, Mice, 030207 dermatology & venereal diseases, 03 medical and health sciences, chemistry.chemical_compound, 0302 clinical medicine, Equivalent, Hyperpigmentation, Cell Line, Tumor, medicine, Animals, Humans, Thymol, Cells, Cultured, Skin, Melanins, Pharmacology, integumentary system, Esters, General Medicine, Molecular biology, In vitro, Staining, 030104 developmental biology, chemistry, Cinnamates, Cell culture, Melanocytes, medicine.symptom

الوصف: Background/Aims: Excessive melanogenesis often causes unaesthetic hyperpigmentation. In a previous report, our group introduced a newly synthesized depigmentary agent, Melasolv™ (3,4,5-trimethoxycinnamate thymol ester). In this study, we demonstrated the significant whitening efficacy of Melasolv using various melanocytes and human skin equivalents as in vitro experimental systems. Methods: The depigmentary effect of Melasolv was tested in melan-a cells (immortalized normal murine melanocytes), α-melanocyte-stimulating hormone (α-MSH)-stimulated B16 murine melanoma cells, primary normal human melanocytes (NHMs), and human skin equivalent (MelanoDerm). The whitening efficacy of Melasolv was further demonstrated by photography, time-lapse microscopy, Fontana-Masson (F&M) staining, and 2-photon microscopy. Results: Melasolv significantly inhibited melanogenesis in the melan-a and α-MSH-stimulated B16 cells. In human systems, Melasolv also clearly showed a whitening effect in NHMs and human skin equivalent, reflecting a decrease in melanin content. F&M staining and 2-photon microscopy revealed that Melasolv suppressed melanin transfer into multiple epidermal layers from melanocytes as well as melanin synthesis in human skin equivalent. Conclusion: Our study showed that Melasolv clearly exerts a whitening effect on various melanocytes and human skin equivalent. These results suggest the possibility that Melasolv can be used as a depigmentary agent to treat pigmentary disorders as well as an active ingredient in cosmetics to increase whitening efficacy.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::2fb2c9885b53b1816bff4b64068ecbecTest
https://doi.org/10.1159/000477356Test

المؤلفون: Yun Kyung Lim, Jung Hun Pi, Chang-Seok Lee, Ji Hong An, Chi Hong Lim, Kyeong Bae Nam

المصدر: Journal of Korean Society on Water Environment. 32:465-474

مصطلحات موضوعية: Land use, Agroforestry, medicine, Plan (archaeology), Environmental science, medicine.symptom, Vegetation (pathology)

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::c32b957b3326352727227553d7fbb2e6Test
https://doi.org/10.15681/kswe.2016.32.5.465Test