80 results on '"Sung Cho"'
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2. Quantitative Analysis of Inorganic Binder Gas Emission Using TG–MS Coupling System Under Casting
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Si-Young Kwak, In-Sung Cho, Kyeong Ho Kim, and Min A Bae
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Mechanics of Materials ,Materials Chemistry ,Metals and Alloys ,Industrial and Manufacturing Engineering - Published
- 2022
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3. Improvement of germinability of lettuce seeds with drum-priming under high temperature condition
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Jong-In Park, Dong-Myung Cho, Jeong-Hee Oh, Ju-Sung Cho, and Nam-Jun Kang
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Plant Science ,Horticulture ,Biotechnology - Published
- 2022
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4. Targeted and high-throughput gene knockdown in diverse bacteria using synthetic sRNAs
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Jae Sung Cho, Dongsoo Yang, Cindy Pricilia Surya Prabowo, Mohammad Rifqi Ghiffary, Taehee Han, Kyeong Rok Choi, Cheon Woo Moon, Hengrui Zhou, Jae Yong Ryu, Hyun Uk Kim, and Sang Yup Lee
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Multidisciplinary ,General Physics and Astronomy ,General Chemistry ,General Biochemistry, Genetics and Molecular Biology - Abstract
Synthetic sRNAs allow knockdown of target genes at translational level, but have been restricted to a limited number of bacteria. Here, we report the development of a broad-host-range synthetic sRNA (BHR-sRNA) platform employing the RoxS scaffold and the Hfq chaperone from Bacillus subtilis. BHR-sRNA is tested in 16 bacterial species including commensal, probiotic, pathogenic, and industrial bacteria, with >50% of target gene knockdown achieved in 12 bacterial species. For medical applications, virulence factors in Staphylococcus epidermidis and Klebsiella pneumoniae are knocked down to mitigate their virulence-associated phenotypes. For metabolic engineering applications, high performance Corynebacterium glutamicum strains capable of producing valerolactam (bulk chemical) and methyl anthranilate (fine chemical) are developed by combinatorial knockdown of target genes. A genome-scale sRNA library covering 2959 C. glutamicum genes is constructed for high-throughput colorimetric screening of indigoidine (natural colorant) overproducers. The BHR-sRNA platform will expedite engineering of diverse bacteria of both industrial and medical interest.
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- 2023
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5. Days alive and out of hospital at 30 days and outcomes of off-pump coronary artery bypass grafting
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Ah Ran Oh, Seung-Hwa Lee, Jungchan Park, Jeong-Jin Min, Jong-Hwan Lee, Seung Yeon Yoo, Ji-Hye Kwon, Dan-Cheong Choi, Wooksung Kim, and Hyun Sung Cho
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Multidisciplinary - Abstract
Days alive and out of hospital (DAOH) is a simple estimator based on the number of days not in hospital within a defined period. In cases of mortality within the period, DAOH is regarded as zero. It has not been validated solely in off-pump coronary artery bypass grafting (OPCAB). This study aimed to demonstrate a correlation between DAOH and outcome of OPCAB. We identified 2211 OPCAB performed from January 2010 to August 2016. We calculated DAOH at 30 and 60 days. We generated a receiver-operating curve and compared outcomes. The median duration of hospital stay after OPCAB was 6 days. The median DAOH values at 30 and 60 days were 24 and 54 days. The estimated thresholds for 3-year mortality for DAOH at 30 and 60 days were 20 and 50 days. Three-year mortality was higher for short DAOH (1.2% vs. 5.7% and 1.1% vs. 5.6% DAOH at 30 and 60 days). After adjustment, the short DAOH 30 group showed significantly higher mortality during 3-year follow-up (hazard ratio 3.07; 95% confidence interval 1.45–6.52; p = 0.004). DAOH at 30 days after OPCAB showed a correlation with 3-year outcomes. DAOH 30 might be a reliable long-term outcome measure that can be obtained within 30 days after surgery.
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- 2023
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6. Serratia silvae sp. nov., Isolated from Forest Soil
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Gyu-Sung Cho, Estelle Mühle, Dominique Clermont, Charles M. A. P. Franz, Ludovic Besaury, Max Rubner-Institut, Collection de l'Institut Pasteur (CIP), Institut Pasteur [Paris] (IP)-Université Paris Cité (UPCité), Fractionnement des AgroRessources et Environnement (FARE), Université de Reims Champagne-Ardenne (URCA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), and La Fondation de FranceLa Fondation du site Paris-Reims
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[SDV]Life Sciences [q-bio] ,General Medicine ,Applied Microbiology and Biotechnology ,Microbiology - Abstract
International audience; The Gram-negative, oxidase-negative, catalase-positive, rod-shaped strain Arafor3T was isolated from forest soil (France). Comparative 16S rRNA gene analysis and phylogenetic analysis based on (1) multilocus sequence analysis (MLSA) with four housekeeping genes (atpD, gyrB, infB and rpoB) and (2) genomes indicated that strain Arafor3T shared 98.83% 16S rRNA gene sequence similarity with the type strain of Serratia fonticola DSM 4576T and was closely related to this same strain in the MLSA and in the phylogenomic tree reconstruction. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) comparisons of strain Arafor3T with its nearest neighbor S. fonticola DSM 4576T showed 93.5% identity and 55.7% sequence similarity, respectively, and were lower than the 96% and 70% species-level cut-off values relating to these analyses (Logan et al. in Int J Syst Evol Microbiol 59:2114–21, 2009, https://doi.org/10.1099/ijs.0.013649-0). The strain differed from S. fonticola in that it was urease and arginine dihydrolase negative. The major fatty acids of strain Arafor3T are C16:0, C16:1 ω7c/C16:1 ω6c, C14:0, C14:0 3-OH/16:1 isoI, and C18:1 ω7c. The major respiratory quinone is Q8. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, and 6 unknown lipids. The mol G + C% content of the genomic DNA of strain Arafor3T was 53.49%. Hence, Arafor3T represents a novel species within the genus Serratia, for which the name Serratia silvae sp. nov. is proposed. The type strain is Arafor3T (=LMG 32338T = CIP 111939T).
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- 2023
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7. Clinical Outcomes of Hepatitis B Virus–Related Hepatocellular Carcinoma Patients with Undetectable Serum HBV DNA Levels
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Wonseok Kang, Joon Hyeok Lee, Seung Woon Paik, Moon Seok Choi, Seonwoo Kim, Dong Hyun Sinn, Yong-Han Paik, Kwang Cheol Koh, Hyun Sung Cho, Geum-Youn Gwak, and Jong-In Chang
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Hepatitis B virus ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Physiology ,medicine.disease_cause ,Antiviral Agents ,Gastroenterology ,Hepatitis B, Chronic ,Risk Factors ,Internal medicine ,medicine ,Humans ,Cumulative incidence ,Retrospective Studies ,business.industry ,Incidence (epidemiology) ,Liver Neoplasms ,Hazard ratio ,virus diseases ,Retrospective cohort study ,Hepatology ,medicine.disease ,digestive system diseases ,Confidence interval ,Hepatocellular carcinoma ,DNA, Viral ,Virus Activation ,business - Abstract
BACKGROUND AND AIMS Some hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) patients show undetectable serum HBV DNA levels at HCC diagnosis. The risk of HBV reactivation and its impact on clinical outcomes are not well-unknown. METHODS This retrospective cohort study included a total of 985 HBV-related HCC patients with undetectable serum HBV DNA levels (
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- 2021
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8. Novel KCNQ4 variants in different functional domains confer genotype- and mechanism-based therapeutics in patients with nonsyndromic hearing loss
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Doo-Yi Oh, Heon Yung Gee, Sang-Yeon Lee, Ami Kim, Jieun An, Bong Jik Kim, Na-Young Yi, Jin Hee Han, Min Young Kim, Seungmin Lee, Chung Lee, Nahyun Kim, Young Ik Koh, Eunku Kim, Hyun Been Choi, Hyun Sung Cho, Woong-Yang Park, Byung Yoon Choi, Tong Mook Kang, Mina Park, Il Soon Choi, and Nayoung K.D. Kim
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Male ,Phosphatidylinositol 4,5-Diphosphate ,0301 basic medicine ,Patch-Clamp Techniques ,Genotype ,Concatemer ,Clinical Biochemistry ,Mutant ,Mutation, Missense ,Context (language use) ,Deafness ,Biology ,Biochemistry ,Article ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Protein Domains ,Genetics research ,Humans ,Homomeric ,Molecular Biology ,KCNQ Potassium Channels ,HEK 293 cells ,Translational research ,Phenotype ,Potassium channel ,Pedigree ,Cell biology ,HEK293 Cells ,030104 developmental biology ,chemistry ,Potassium ,Molecular Medicine ,Female ,030217 neurology & neurosurgery ,KCNQ4 - Abstract
Loss-of-function variant in the gene encoding the KCNQ4 potassium channel causes autosomal dominant nonsyndromic hearing loss (DFNA2), and no effective pharmacotherapeutics have been developed to reverse channel activity impairment. Phosphatidylinositol 4,5-bisphosphate (PIP2), an obligatory phospholipid for maintaining KCNQ channel activity, confers differential pharmacological sensitivity of channels to KCNQ openers. Through whole-exome sequencing of DFNA2 families, we identified three novel KCNQ4 variants related to diverse auditory phenotypes in the proximal C-terminus (p.Arg331Gln), the C-terminus of the S6 segment (p.Gly319Asp), and the pore region (p.Ala271_Asp272del). Potassium currents in HEK293T cells expressing each KCNQ4 variant were recorded by patch-clamp, and functional recovery by PIP2 expression or KCNQ openers was examined. In the homomeric expression setting, the three novel KCNQ4 mutant proteins lost conductance and were unresponsive to KCNQ openers or PIP2 expression. Loss of p.Arg331Gln conductance was slightly restored by a tandem concatemer channel (WT-p.R331Q), and increased PIP2 expression further increased the concatemer current to the level of the WT channel. Strikingly, an impaired homomeric p.Gly319Asp channel exhibited hyperactivity when a concatemer (WT-p.G319D), with a negative shift in the voltage dependence of activation. Correspondingly, a KCNQ inhibitor and chelation of PIP2 effectively downregulated the hyperactive WT-p.G319D concatemer channel. Conversely, the pore-region variant (p.Ala271_Asp272del) was nonrescuable under any condition. Collectively, these novel KCNQ4 variants may constitute therapeutic targets that can be manipulated by the PIP2 level and KCNQ-regulating drugs under the physiological context of heterozygous expression. Our research contributes to the establishment of a genotype/mechanism-based therapeutic portfolio for DFNA2., Hearing loss: genetically tailored treatment strategy for congenital deafness People with a certain type of inherited hearing loss may stand to benefit from a personalized, genetically tailored treatment strategy. A research team from South Korea led by Byung Yoon Choi from Seoul National University College of Medicine identified three new mutations in KCNQ4, a gene that encodes a potassium channel protein found in the inner ear, that can cause congenital deafness. Strikingly, the authors identified the first hyperactive KCNQ4 variant. They inserted these gene variants into human cells in culture, and found that drugs known to affect the activity of this channel protein had different effects on different mutations. Impairments caused by two of the variants were prevented by drug treatment; the third variant proved resistant to the same therapeutic approach. The authors propose further validating the therapeutic responsiveness of different KCNQ4 variants in genetically engineered mice.
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- 2021
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9. Health risk assessment for multimedia exposure of formaldehyde emitted by chemical accident
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Si Hyun Park, Danki Yoon, Cheol-Min Lee, Hye-Won Lee, Jeong-In Jeon, Hee Seok Kim, Hyong-Jin Hong, Ji-Won Choi, Yong-Sung Cho, Eun-Min Cho, Hye-Kwan Kong, and Hui-Been Lim
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Pollutant ,Inhalation exposure ,Health risk assessment ,Multimedia ,Health, Toxicology and Mutagenesis ,Formaldehyde ,Poison control ,General Medicine ,Chemical accident ,010501 environmental sciences ,computer.software_genre ,01 natural sciences ,Pollution ,Occupational safety and health ,chemistry.chemical_compound ,chemistry ,Environmental Chemistry ,Ecotoxicology ,Environmental science ,computer ,0105 earth and related environmental sciences - Abstract
This study was conducted to provide basic data for chemical accident response by assessing the health risks of residents living near a chemical accident site due to long-term exposure. The study considered the temporal concentration changes of the leaked chemical (i.e., its behavior in the environment and dilution) until its extinction. A virtual chemical accident was assumed, in which 40 t of formaldehyde was accidentally discharged for 1 h in Ulsan Metropolitan City, Korea. Formaldehyde concentrations over time in each environmental medium after the accident were calculated using a multimedia environmental dynamics model. Exposure subjects divided into four age groups were considered. Carcinogenic risks due to respiration and non-carcinogenic risks due to soil intake were assessed. For all the age groups, the excess cancer risk did not exceed 1.0 × 10-6, indicating that no harmful health impact was caused by inhalation exposure to formaldehyde. The hazard index exceeded 1 for all the age groups, confirming that harmful health impacts were caused by exposure to soil containing the formaldehyde. This study is the first to assess chronic health risks by reflecting long-term residual and temporal concentration changes of a pollutant released in a chemical accident in each environmental medium until its extinction. This work is also significant in that it reflects the exposure characteristics of the toxic chemical.
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- 2020
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10. Filling metal–organic framework mesopores with TiO2 for CO2 photoreduction
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Xiaohui Xu, Peter Oleynikov, Chao Wang, Jun Cheng, Hexiang Deng, Deng Ding, Jie Wu, Osamu Terasaki, Yi Zhou, Mei Jia, Ling Zan, Yanhang Ma, Tianyou Peng, Hae Sung Cho, and Zhuo Jiang
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Multidisciplinary ,Materials science ,Composite number ,Energy conversion efficiency ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Chromium ,chemistry ,Chemical engineering ,Photocatalysis ,Molecule ,Metal-organic framework ,0210 nano-technology ,Porosity ,Mesoporous material - Abstract
Metal–organic frameworks (MOFs)1–3 are known for their specific interactions with gas molecules4,5; this, combined with their rich and ordered porosity, makes them promising candidates for the photocatalytic conversion of gas molecules to useful products6. However, attempts to use MOFs or MOF-based composites for CO2 photoreduction6–13 usually result in far lower CO2 conversion efficiency than that obtained from state-of-the-art solid-state or molecular catalysts14–18, even when facilitated by sacrificial reagents. Here we create ‘molecular compartments’ inside MOF crystals by growing TiO2 inside different pores of a chromium terephthalate-based MOF (MIL-101) and its derivatives. This allows for synergy between the light-absorbing/electron-generating TiO2 units and the catalytic metal clusters in the backbones of MOFs, and therefore facilitates photocatalytic CO2 reduction, concurrent with production of O2. An apparent quantum efficiency for CO2 photoreduction of 11.3 per cent at a wavelength of 350 nanometres is observed in a composite that consists of 42 per cent TiO2 in a MIL-101 derivative, namely, 42%-TiO2-in-MIL-101-Cr-NO2. TiO2 units in one type of compartment in this composite are estimated to be 44 times more active than those in the other type, underlining the role of precise positioning of TiO2 in this system. Investigation of a chromium-based metal–organic framework shows that the location of added TiO2 inside specific mesopores strongly affects the ability of the material to catalyse photoreduction of CO2.
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- 2020
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11. Prognostication of a 13-immune-related-gene signature in patients with early triple-negative breast cancer
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Jeong Eon Lee, Seok Jin Nam, Ji-Yeon Kim, Seok Won Kim, Hyun Sung Cho, Yeon Hee Park, Insuk Sohn, Sook Young Woo, Hae Hyun Jung, Young-Hyuck Im, Jin Seok Ahn, and Eun Yoon Cho
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0301 basic medicine ,Oncology ,Cancer Research ,medicine.medical_specialty ,Multivariate analysis ,biology ,Receiver operating characteristic ,business.industry ,medicine.medical_treatment ,Immunotherapy ,medicine.disease ,PTPRC ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Breast cancer ,030220 oncology & carcinogenesis ,Internal medicine ,medicine ,biology.protein ,Stage (cooking) ,business ,MAPK1 ,Triple-negative breast cancer - Abstract
We investigated the expression profiles of immune genes in patients with triple-negative breast cancer (TNBC) to identify the prognostic value of immune genes and their clinical implications. NanoString nCounter Analysis of 770 immune-related genes was used to measure immune gene expression in patients with TNBC who underwent curative surgery followed by adjuvant chemotherapy at Samsung Medical Center between 2000 and 2004. Statistical analyses were conducted to identify the associations between gene expression and distant recurrence-free survival (DRFS). Of 1189 patients who underwent curative BC surgery, 200 TNBC patients were included and stage was the only clinical factor predictive of DRFS. In terms of immune genes, 155 of 770 genes were associated with DRFS (p
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- 2020
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12. Practical methodology for gametophyte proliferation and sporophyte production in green penny fern (Lemmaphyllum microphyllum C. Presl) using mechanical fragmentation
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Kyungtae Park, Bo Kook Jang, Ju Sung Cho, and Cheol Hee Lee
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0106 biological sciences ,0301 basic medicine ,Gametophyte ,biology ,Mechanical fragmentation ,Lemmaphyllum microphyllum ,Sporophyte ,Plant Science ,biology.organism_classification ,01 natural sciences ,Acclimatization ,03 medical and health sciences ,030104 developmental biology ,Botany ,Ornamental plant ,Spore germination ,Fern ,010606 plant biology & botany ,Biotechnology - Abstract
Propagation of gametophytes and sporophytes using mechanical fragmentation has been considered a suitable method for mass production of ferns. This study aimed to develop a practical propagation method for Lemmaphyllum microphyllum C. Presl, which is a fern of significant ornamental and medicinal value. Gametophytes were obtained through in vitro spore germination and used for propagation experiments. The gametophyte was mechanically fragmented using a scalpel into small fragments, which were then used to investigate gametophyte proliferation. In addition, the gametophyte was fragmented using a blender and then used to study sporophyte formation. Optimal proliferation conditions of the gametophyte were determined using Murashige and Skoog (MS) basal medium (double-, full-, half-, quarter-strength), Knop medium, and medium components (sucrose, nitrogen sources, activated charcoal), at various concentrations. The fresh weight of the gametophyte was 14-fold higher than that of gametophytes (300 mg) used as culture material, when cultured on double-strength MS. Moreover, 1 g of the gametophyte fragmented in 25 mL of distilled water formed more than 430 sporophytes in a soil mixture in an area of 7.5 cm2. The sporophytes were successfully cultivated in the greenhouse after acclimation. A large-scale production method for L. microphyllum that can be easily implemented in a fern production farm is outlined.
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- 2020
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13. Author Correction: Direct patterning of colloidal quantum dots with adaptable dual-ligand surface
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Donghyo Hahm, Jaemin Lim, Hyeokjun Kim, Jin-Wook Shin, Seongkwon Hwang, Seunghyun Rhee, Jun Hyuk Chang, Jeehye Yang, Chang Hyeok Lim, Hyunwoo Jo, Beomgyu Choi, Nam Sung Cho, Young-Shin Park, Doh C. Lee, Euyheon Hwang, Seungjun Chung, Chan-mo Kang, Moon Sung Kang, and Wan Ki Bae
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Biomedical Engineering ,General Materials Science ,Bioengineering ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics - Published
- 2023
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14. Culture types and period impact gametophyte morphogenesis and sporophyte formation of eastern bracken
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Cheol Hee Lee, Shin-Ho Kang, Bo-Kook Jang, and Ju-Sung Cho
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0106 biological sciences ,0301 basic medicine ,QH301-705.5 ,Plant Science ,01 natural sciences ,SB1-1110 ,Liquid suspension culture ,03 medical and health sciences ,chemistry.chemical_compound ,Murashige and Skoog medium ,Botany ,Genetics ,Biology (General) ,Abscisic acid ,Gametophyte ,biology ,Research ,Plant culture ,Pteridium aquilinum var. latiusculum (Desv.) Underw. ex A. Heller ,Sporophyte ,Mechanical fragmentation ,biology.organism_classification ,Plant cell ,Phytohormones ,030104 developmental biology ,chemistry ,Pteridium aquilinum ,Subculture (biology) ,Zeatin ,010606 plant biology & botany ,Biotechnology - Abstract
Background Liquid suspension culture efficiently proliferates plant cells and can be applied to ferns because it rapidly increases the fresh weight of gametophytes. This study assessed gametophyte proliferation and sporophyte production of Pteridium aquilinum var. latiusculum using a suspension culture method. Results The growth curve linear phase of gametophyte cells was confirmed between 9 and 18 days of culture, and the subculture cycle was determined to be 2 weeks. A double-strength MS medium (fresh weight, 18.0 g) containing 2% sucrose and NH4+:NO3− (120 mM, 40:80) was found to be the optimal liquid medium. Gametophytes obtained after suspension culture for 18 days did not normally form sporophytes in an ex vitro soil environment. However, this issue was resolved after changing the culture type or extending the culture period to 6 weeks. A short suspension culture period increased the fresh weight of fragmented and homogenized gametophytes but yielded numerous relatively immature gametophytes (globular forms of branching gametophytes, BG). Furthermore, differences in gametophyte morphogenesis and development were indicated by changes in endogenous phytohormone content. BG with immature development exhibited high accumulation of zeatin, jasmonic acid, and salicylic acid, and relatively low levels of abscisic acid and indole-3-acetic acid. The immature development of gametophytes directly affected sporophyte formation. Conclusions This study maximized the advantages of liquid suspension culture using eastern bracken gametophytes and provides data to resolve any associated issues, thus facilitating efficient bracken production.
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- 2021
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15. Global phylogeography and ancient evolution of the widespread human gut virus crAssphage
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Steven R. Head, Emma Billings, Stephen Wandro, Jane M. Carlton, Alexandra Zhernakova, A. Murat Eren, Zhe Xue Quan, Anders S. Nilsson, Gyu Sung Cho, Udi Qimron, Martin M. Kowalewski, John Shimashita, Gillian A.O. Rice, Frank Møller Aarestrup, Elyse Stachler, Vito Adrian Cantu, Linsey C. Marr, Alessandro Rossi, Angela McCann, Colin Hill, Cristina García-Aljaro, Kristen M. Gulino, David A. Lipson, Rene S. Hendriksen, Bryan A. White, Bas E. Dutilh, Bashir Mukhtar Elwasila, Karla Mazankova, Alexander V. Tyakht, Julia M. Maritz, Ronan Strain, Rodrigo De la Iglesia, Ramy K. Aziz, Kyle Levi, Alan Twaddle, Alejandro Reyes Muñoz, Katelyn McNair, Alejandro A. Vega, Nathaniel J. Dominy, Abigail E. Asangba, Robert Edwards, Rasha Odeh, Olivia D. Nigro, Gunduz Ahmadov, Raúl R. Raya, Nam Nguyen, Charles M. A. P. Franz, Nicole Trefault, Adán Ramírez-Rojas, Michael P. Doane, Randall E. Junge, Patrick A. de Jonge, Jingyuan Fu, Taylor O'Connell, Mike Cranfield, German Tapia, Heikki Hyöty, Nicolás A. Villagra, Cisca Wijmenga, Henrike Zschach, Megan M. Morris, Franklin L. Nobrega, Elena N. Ilina, David Thomas McCarthy, Daniel Cazares, Silvia Monteiro, Lawrence Mugisha, Daniel A. Cuevas, Horst Neve, Przemyslaw Decewicz, John M. Haggerty, Ricardo Santos, Deepak Kumaresan, Shahar Molshanski-Mor, Andrew S. Whiteley, Benjamin Moreira-Grez, Rebecca M. Stumpf, Katrine Whiteson, Holly M. Norman, Jeremy J. Barr, Peter C. Fineran, Jeroen Wagemans, Samuel L. Díaz Muñoz, Kim Reasor, Elizabeth A. Dinsdale, Mitchell T. Irwin, Aaron J. Prussin, Mohammadali Khan Mirzaei, Maite Muniesa, Christelle Desnues, Montserrat Llagostera, Rob Lavigne, Abeer Alassaf, Tess Condeff, Petra Rainetova, María Mercedes Zambrano, Adrian Cazares, Elodie Ghedin, Alexander Kurilshikov, Lukasz Dziewit, Thomas C. Jeffries, Mary Ann Ugochi Ibekwe, Eugenia S. Lisitsyna, Juan Jofre, Pedro J. Torres, Maria Ohaeri, Mariana Piuri, Andrew Oliver, Steven R. Leigh, Ondrej Cinek, Stan J. J. Brouns, Josefa Antón, Pilar Cortés, Kyle Bibby, Lars C. Stene, Pablo Vinuesa, Scott T. Kelley, San Diego State University (SDSU), Consejo Nacional de Investigaciones Científicas y Técnicas [Buenos Aires] (CONICET), Microbes évolution phylogénie et infections (MEPHI), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Institut méditerranéen d'océanologie (MIO), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Laboratory of Gene Technology, Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Monash University [Clayton], University Medical Center Groningen [Groningen] (UMCG), Centro de Investigación Oceanográfica en el Pacífico Sur Oriental (COPAS), Universidad de Concepción - University of Concepcion [Chile], Dartmouth College [Hanover], Marine Biological Laboratory (MBL), University of Chicago, Department of Safety and Quality of Fruit and Vegetables, Federal Research Institute for Nutrition and Food, Department of Parasite and Virus Genomics, The Institute for Genomic Research (TIGR), The Scripps Research Institute [La Jolla, San Diego], Danmarks Tekniske Universitet = Technical University of Denmark (DTU), Queen's University [Belfast] (QUB), Hawkesbury Institute for the Environment [Richmond] (HIE), Western Sydney University, CREW - Center for Research on the English-speaking World - EA 4399 (CREW), Université Sorbonne Nouvelle - Paris 3, School of Microbiology, University College Cork (UCC), Université du Cap-Vert, université du Cap-Vert, Department of Microbiology [University of Barcelona], Dept Microbiol & Biotechnol, Max Rubner Inst, Department of Pharmaceutical Biosciences, Uppsala University, University of Manchester [Manchester], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Getulio Vargas Foundation, Centro Geofísico de Canarias, Instituto Geografico Nacional, Laboratorio de Patogénesis Molecular y Antimicrobianos, Facultad de Medicina , Universidad Andres Bello, University of Illinois, University of Illinois System, National Severe Storms Laboratory (NSSL), National Oceanic and Atmospheric Administration (NOAA), Department of Medical Genetics, HMNC Brain Health, Utrecht University [Utrecht], Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU), Universidad de Concepción [Chile], The SCRIPPS Research Institute (SCRIPPS), University of California [Los Angeles] (UCLA), University of California-University of California, Technical University of Denmark [Lyngby] (DTU), Biomolecular Imaging and Proteomics, National Center for Mass Spectrometry Imaging, Uppsala University, Universidad de Alicante. Departamento de Fisiología, Genética y Microbiología, Ecología Microbiana Molecular, Theoretical Biology and Bioinformatics, Sub Bioinformatics, Groningen Institute for Gastro Intestinal Genetics and Immunology (3GI), Translational Immunology Groningen (TRIGR), and Center for Liver, Digestive and Metabolic Diseases (CLDM)
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DYNAMICS ,Male ,BACTERIAL ,ACCURACY ,Lineage (evolution) ,Filogeografia ,Microbiología ,Applied Microbiology and Biotechnology ,Genome ,Biological Coevolution ,MULTIPLE SEQUENCE ALIGNMENT ,TRACKING ,Feces ,Tumours of the digestive tract Radboud Institute for Molecular Life Sciences [Radboudumc 14] ,Bacteriophages ,Viral ,Clade ,Phylogeny ,ComputingMilieux_MISCELLANEOUS ,2. Zero hunger ,0303 health sciences ,Environmental microbiology ,[SDV.BID.EVO]Life Sciences [q-bio]/Biodiversity/Populations and Evolution [q-bio.PE] ,crAssphage ,READ ALIGNMENT ,GENOME ,Phylogeography ,[SDV.MP.VIR]Life Sciences [q-bio]/Microbiology and Parasitology/Virology ,Female ,Life Sciences & Biomedicine ,Primates ,Microbiology (medical) ,Lineage (genetic) ,Evolution ,Immunology ,Coronacrisis-Taverne ,Microbiota intestinal ,BIOLOGY ,Biology ,Microbiology ,Virus ,DNA sequencing ,Article ,03 medical and health sciences ,All institutes and research themes of the Radboud University Medical Center ,SDG 3 - Good Health and Well-being ,Phylogenetics ,Genetics ,Animals ,Humans ,Human virome ,ALGORITHM ,Microbiome ,Genomes ,Gastrointestinal microbiome ,030304 developmental biology ,[SDV.EE.SANT]Life Sciences [q-bio]/Ecology, environment/Health ,Science & Technology ,Widespread human gut virus ,Bacteroidetes ,030306 microbiology ,Genetic Variation ,DNA ,Cell Biology ,biology.organism_classification ,Gastrointestinal Microbiome ,MICROBIOME ,Evolutionary biology ,DNA, Viral - Abstract
Microbiomes are vast communities of microorganisms and viruses that populate all natural ecosystems. Viruses have been considered to be the most variable component of microbiomes, as supported by virome surveys and examples of high genomic mosaicism. However, recent evidence suggests that the human gut virome is remarkably stable compared with that of other environments. Here, we investigate the origin, evolution and epidemiology of crAssphage, a widespread human gut virus. Through a global collaboration, we obtained DNA sequences of crAssphage from more than one-third of the world's countries and showed that the phylogeography of crAssphage is locally clustered within countries, cities and individuals. We also found fully colinear crAssphage-like genomes in both Old-World and New-World primates, suggesting that the association of crAssphage with primates may be millions of years old. Finally, by exploiting a large cohort of more than 1,000 individuals, we tested whether crAssphage is associated with bacterial taxonomic groups of the gut microbiome, diverse human health parameters and a wide range of dietary factors. We identified strong correlations with different clades of bacteria that are related to Bacteroidetes and weak associations with several diet categories, but no significant association with health or disease. We conclude that crAssphage is a benign cosmopolitan virus that may have coevolved with the human lineage and is an integral part of the normal human gut virome. ispartof: NATURE MICROBIOLOGY vol:4 issue:10 pages:1727-1736 ispartof: location:England status: published
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- 2019
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16. A methodology for large-scale Athyrium sheareri gametophyte proliferation and sporophyte production using tissue culture
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Cheol Hee Lee, Bo Kook Jang, Ju Sung Cho, and Kyungtae Park
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0106 biological sciences ,0301 basic medicine ,Gametophyte ,biology ,Athyrium ,Sporophyte ,Plant Science ,biology.organism_classification ,01 natural sciences ,03 medical and health sciences ,Tissue culture ,030104 developmental biology ,Murashige and Skoog medium ,Botany ,Ornamental plant ,Spore germination ,Fern ,010606 plant biology & botany ,Biotechnology - Abstract
Tissue culture methods using gametophytes are considered the easiest ways to mass-produce fern sporophytes. The aim of this study was to develop a practical propagation method for the ornamental fern, Athyrium sheareri. The gametophytes obtained from in vitro spore germination were used as experimental materials. We used the chopping method to investigate the culturing conditions for proliferating gametophytes and the blending method for evaluating the mass production of sporophytes in mixed soil. Gametophyte proliferation was determined via Knop medium, various concentrations of Murashige and Skoog (MS) basal medium (1, 1/2, 1/4), and media components (sucrose, nitrogen source, and activated charcoal). The fresh weight of the gametophytes increased by more than 24-fold in 1/2 MS medium. In addition, 1 g of gametophyte could produce a maximum of 255.3 sporophytes in a mixed soil of 7.5 cm2 area. Treating gametophytes with exogenous plant growth regulators promoted the formation and growth of sporophytes. The cultivated young sporophytes were acclimated and successfully grown in greenhouses. We developed a mass production protocol for A. sheareri sporophytes suitable for field application, which is expected to have commercial value.
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- 2019
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17. Propagation methods for gametophyte proliferation and sporophyte formation in silver cloak fern (Cheilanthes argentea)
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Bo Kook Jang, Ju Sung Cho, and Cheol Hee Lee
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Gametophyte ,biology ,Sporophyte ,Plant Science ,Horticulture ,biology.organism_classification ,Tissue culture ,Murashige and Skoog medium ,Botany ,Ornamental plant ,Spore germination ,Gibberellin ,Fern ,Biotechnology - Abstract
Cheilanthes argentea (S.G. Gmel.) Kunze is a highly valued indigenous/endemic Korean bracken species used for ornamental purposes. In this study, we developed a practical proliferation method for mass production of C. argentea plants using tissue culture. The gametophyte proliferation using the chopping method produced gametophytes that were morphologically identical to those obtained from in vitro spore germination. This new method increased plant fresh weight by more than 40-fold, from 300 mg to 12.7 g, in Murashige and Skoog medium. A blending method was used to produce 74.3 sporophytes in 7.5-cm2 plastic pots using 1 g of gametophytes. Furthermore, addition of exogenous gibberellin promoted sporophyte development and growth, suggesting the possibility of controlling the number of sporophytes formed. However, further studies are needed to explain the effect of exogenous gibberellin, which is closely related to the sex-determining hormone antheridiogen, on the number of sporophytes and its mechanism of action. Our new tissue culture system is capable of mass proliferation of C. argentea gametophytes in vitro and the formation of sporophytes by ex vitro preparation using the generated gametophytes.
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- 2019
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18. Pentamidine Inhibits Titanium Particle-Induced Osteolysis In Vivo and Receptor Activator of Nuclear Factor-κB Ligand-Mediated Osteoclast Differentiation In Vitro
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Kiryeong Kim, Hye Jung Ihn, Hye Sung Cho, and Eui Kyun Park
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musculoskeletal diseases ,0303 health sciences ,Osteolysis ,biology ,Chemistry ,0206 medical engineering ,Biomedical Engineering ,Acid phosphatase ,Medicine (miscellaneous) ,02 engineering and technology ,Bone tissue ,medicine.disease ,020601 biomedical engineering ,03 medical and health sciences ,IκBα ,medicine.anatomical_structure ,RANKL ,In vivo ,Osteoclast ,Cancer research ,biology.protein ,medicine ,030304 developmental biology ,Pentamidine ,medicine.drug - Abstract
Wear debris-induced osteolysis leads to periprosthetic loosening and subsequent prosthetic failure. Since excessive osteoclast formation is closely implicated in periprosthetic osteolysis, identification of agents to suppress osteoclast formation and/or function is crucial for the treatment and prevention of wear particle-induced bone destruction. In this study, we examined the potential effect of pentamidine treatment on titanium (Ti) particle-induced osteolysis, and receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis. The effect of pentamidine treatment on bone destruction was examined in Ti particle-induced osteolysis mouse model. Ti particles were implanted onto mouse calvaria, and vehicle or pentamidine was administered for 10 days. Then, calvarial bone tissue was analyzed using micro-computed tomography and histology. We performed in vitro osteoclastogenesis assay using bone marrow-derived macrophages (BMMs) to determine the effect of pentamidine on osteoclast formation. BMMs were treated with 20 ng/mL RANKL and 10 ng/mL macrophage colony-stimulating factor in the presence or absence of pentamidine. Osteoclast differentiation was determined by tartrate-resistant acid phosphatase staining, real-time polymerase chain reaction, and immunofluorescence staining. Pentamidine administration decreased Ti particle-induced osteoclast formation significantly and prevented bone destruction compared to the Ti particle group in vivo. Pentamidine also suppressed RANKL-induced osteoclast differentiation and actin ring formation markedly, and inhibited the expression of nuclear factor of activated T cell c1 and osteoclast-specific genes in vitro. Additionally, pentamidine also attenuated RANKL-mediated phosphorylation of IκBα in BMMs. These results indicate that pentamidine is effective in inhibiting osteoclast formation and significantly attenuates wear debris-induced bone loss in mice.
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- 2019
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19. Periodicity analysis using weighted sequential pattern in recommending service
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Young Sung Cho, Song Chul Moon, and Won Shik Na
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Service (business) ,Association rule learning ,Computer Networks and Communications ,Process (engineering) ,Computer science ,business.industry ,Big data ,020206 networking & telecommunications ,02 engineering and technology ,Recommender system ,computer.software_genre ,Purchasing ,Product (business) ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Data mining ,business ,computer ,Software - Abstract
Nowadays, due to escalating the demands of the direct purchase of e-commerce with many kinds of item, the demand for e-commerce is exploding. The recommender system finds items for customer easily and targets in customers for the e-commerce firms easily by an automated recommending process. And also, association rules are often used to facilitate product sales in marketing pattern analysis through recommender systems in e-commerce. This paper takes aim at a new recommending service in e-commerce using periodicity analysis of weighted sequential pattern. In e-commerce, we need the FRAT segmentation method based on the various items purchased by the customer, to reflect the weights and perform the pre-processing tasks using sequential patterns for period analysis. We apply an effective incremental sequential data mining method that adds incremental purchasing data as a change of the four season changes. As a result, we suggest a recommendation service for micro-marketing of e-commerce based on big data analysis for promoting e-commerce purchasing, which satisfies customer’s taste with various products of e-commerce. To check the performance of the proposal, we tested the data set with the same conditions as before. As a result, the proposed system is more efficient than the other systems in the results of system evaluation.
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- 2019
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20. A comprehensive metabolic map for production of bio-based chemicals
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Woo Dae Jang, Ko Yoo Sung, Tong Un Chae, Jae Ho Shin, Yu Sin Jang, Je Woong Kim, Hyun Uk Kim, Jae Sung Cho, Sang Yup Lee, and Dong In Kim
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business.industry ,Process Chemistry and Technology ,Bio based ,Bioengineering ,Chemical industry ,Raw material ,Biochemistry ,Catalysis ,Renewable energy ,Metabolic engineering ,Renewable biomass ,Production (economics) ,Environmental science ,Biochemical engineering ,business - Abstract
Production of industrial chemicals using renewable biomass feedstock is becoming increasingly important to address limited fossil resources, climate change and other environmental problems. To develop high-performance microbial cell factories, equivalent to chemical plants, microorganisms undergo systematic metabolic engineering to efficiently convert biomass-derived carbon sources into target chemicals. Over the past two decades, many engineered microorganisms capable of producing natural and non-natural chemicals have been developed. This Review details the current status of representative industrial chemicals that are produced through biological and/or chemical reactions. We present a comprehensive bio-based chemicals map that highlights the strategies and pathways of single or multiple biological reactions, chemical reactions and combinations thereof towards production of particular chemicals of interest. Future challenges are also discussed to enable production of even more diverse chemicals and more efficient production of chemicals from renewable feedstocks.
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- 2019
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21. Identifying molecular targets for reverse aging using integrated network analysis of transcriptomic and epigenomic changes during aging
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Yun Sung Cho, Yeonsu Jeon, Yeon Kyung Kim, Kwang-Hyun Cho, Jong Bhak, Hwang-Yeol Lee, and Jae Young Jang
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Adult ,Male ,0301 basic medicine ,Aging ,Science ,Systems analysis ,Computational biology ,Biology ,Article ,Gene regulatory networks ,Transcriptome ,Epigenome ,03 medical and health sciences ,0302 clinical medicine ,Biomarkers of aging ,Gene expression ,Humans ,Epigenetics ,Muscle, Skeletal ,Gene ,Aged ,Epigenomics ,Neurons ,Muscle Weakness ,Multidisciplinary ,RNA ,Alopecia ,DNA Methylation ,Middle Aged ,Regulatory networks ,Skin Aging ,Ageing ,030104 developmental biology ,DNA methylation ,Medicine ,Female ,Biomarkers ,030217 neurology & neurosurgery - Abstract
Aging is associated with widespread physiological changes, including skeletal muscle weakening, neuron system degeneration, hair loss, and skin wrinkling. Previous studies have identified numerous molecular biomarkers involved in these changes, but their regulatory mechanisms and functional repercussions remain elusive. In this study, we conducted next-generation sequencing of DNA methylation and RNA sequencing of blood samples from 51 healthy adults between 20 and 74 years of age and identified aging-related epigenetic and transcriptomic biomarkers. We also identified candidate molecular targets that can reversely regulate the transcriptomic biomarkers of aging by reconstructing a gene regulatory network model and performing signal flow analysis. For validation, we screened public experimental data including gene expression profiles in response to thousands of chemical perturbagens. Despite insufficient data on the binding targets of perturbagens and their modes of action, curcumin, which reversely regulated the biomarkers in the experimental dataset, was found to bind and inhibit JUN, which was identified as a candidate target via signal flow analysis. Collectively, our results demonstrate the utility of a network model for integrative analysis of omics data, which can help elucidate inter-omics regulatory mechanisms and develop therapeutic strategies against aging.
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- 2021
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22. Effects of knee osteoarthritis severity on inter-joint coordination and gait variability as measured by hip-knee cyclograms
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Seong Ho Jang, Jaehyeon Park, In Young Kim, Jae sung Cho, Hyojin Lee, and Jongshill Lee
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Male ,musculoskeletal diseases ,medicine.medical_specialty ,Science ,Osteoarthritis ,Knee Joint ,Severity of Illness Index ,Article ,Perimeter ,03 medical and health sciences ,0302 clinical medicine ,Physical medicine and rehabilitation ,Humans ,Medicine ,Knee ,Gait ,Aged ,030203 arthritis & rheumatology ,Disability ,Hip ,Multidisciplinary ,business.industry ,Stance phase ,Middle Aged ,Osteoarthritis, Knee ,musculoskeletal system ,medicine.disease ,Ageing ,Outcomes research ,Female ,business ,Range of motion ,human activities ,030217 neurology & neurosurgery - Abstract
Inter-joint coordination and gait variability in knee osteoarthritis (KOA) has not been well investigated. Hip-knee cyclograms can visualize the relationship between the hip and knee joint simultaneously. The aim of this study was to elucidate differences in inter-joint coordination and gait variability with respect to KOA severity using hip-knee cyclograms. Fifty participants with KOA (early KOA, n = 20; advanced KOA, n = 30) and 26 participants (≥ 50 years) without KOA were recruited. We analyzed inter-joint coordination by hip-knee cyclogram parameters including range of motion (RoM), center of mass (CoM), perimeter, and area. Gait variability was assessed by the coefficient of variance (CV) of hip-knee cyclogram parameters. Knee RoM was significantly reduced and total perimeter tended to be decreased with KOA progression. KOA patients (both early and advanced) had reduced stance phase perimeter, swing phase area, and total area than controls. Reduced knee CoM and swing phase perimeter were observed only in advanced KOA. Both KOA groups had a greater CV for CoM, knee RoM, perimeter (stance phase, swing phase and total) and swing phase area than the controls. Increased CV of hip RoM was only observed in advanced KOA. These results demonstrate that hip-knee cyclograms can provide insights into KOA patient gait.
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- 2021
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23. Optimal conditions for spore germination and gametophyte and sporophyte production in the autumn fern Dryopteris erythrosora
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Bo Kook Jang, Cheol Hee Lee, Ju Sung Cho, and Hyuk Joon Kwon
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0106 biological sciences ,0301 basic medicine ,Gametophyte ,biology ,Sporophyte ,Plant Science ,Horticulture ,biology.organism_classification ,01 natural sciences ,Dryopteris ,Spore ,03 medical and health sciences ,030104 developmental biology ,Germination ,Seedling ,Spore germination ,Prothallium ,010606 plant biology & botany ,Biotechnology - Abstract
Dryopteris erythrosora (D. C. Eaton) Kuntze is used as an ornamental horticultural crop and landscaping plant, and it is a plant with high development value as an herbal medicine, but there are few studies to proliferate a large amount of plants. This study aimed to determine a suitable method for spore germination, gametophyte proliferation, sporophyte formation, and seedling production in D. erythrosora. Spore germination rate was highest in 1/2 × Murashige and Skoog (MS) medium (92.8%). A suitable medium for prothallus proliferation was selected based on gametophytes produced from germinated spores. A 1 × MS medium was most effective for gametophyte proliferation and active organ formation; moreover, 1 × MS medium containing 1% sucrose without activated charcoal was the most effective growth condition for inducing gametophyte growth and development. The suitable culture soil composition for sporophyte formation was investigated by varying the ratio of horticultural substrate, peat moss, perlite, and decomposed granite. We found that a 2:1 (v:v) mixture of horticultural substrate and perlite accelerated sporophyte formation (155 units). Furthermore, suitable seedlings and transplants for sporophyte seedling growth were determined by varying the ratio of horticultural substrate and decomposed granite, as well as plug tray cell size. For sporophyte seedlings, the greatest growth in root length (92.9 mm) and the most aerial and underground fresh weight (234.1 and 40.3 g, respectively) were observed in a mixture of horticultural substrate and decomposed granite at a 1:2 (v:v) ratio. Our results using tissue culture technology will be provided as a mass production method for substantial industrialization of D. erythrosora plants.
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- 2018
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24. Scoliosis Screening through a Machine Learning Based Gait Analysis Test
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Young Shin Cho, Seong Ho Jang, Chang-Soo Han, Ye Soo Park, Hyeok Dong Lee, Young Hoon Ji, Mi-Jung Kim, Jae sung Cho, Sang Bok Moon, and Sung Young Lee
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Computer science ,0206 medical engineering ,Feature selection ,02 engineering and technology ,Kinematics ,Scoliosis ,Machine learning ,computer.software_genre ,Industrial and Manufacturing Engineering ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Segmentation ,Electrical and Electronic Engineering ,Cobb angle ,business.industry ,Mechanical Engineering ,medicine.disease ,020601 biomedical engineering ,Gait ,Support vector machine ,Gait analysis ,Artificial intelligence ,business ,computer ,030217 neurology & neurosurgery - Abstract
This study discussed application of a machine learning approach (Support vector machine, SVM) for the automatic cognition of gait changes due to scoliosis using gait measures: kinematic based on gait phase segmentation. The gaits of 18 controls and 24 scoliosis patients were recorded and analyzed using inertial measurement unit (IMU)-based systems during normal walking. Altogether, 72 gait features were extracted for developing gait recognition models. Cross-validation test results indicated that the performance of SVM was 90.5% to recognize scoliosis patients and controls gait patterns. When features were optimally selected, a feature selection algorithm could effectively distinguish the age groups with 95.2% accuracy. Applying the method that the previous test used, the severity of scoliosis was classified after clinician labeled the severity based on the Cobb angle. Test results indicated an accuracy of 81.0% by the SVM to recognize scoliosis severity gait patterns. Optimal selected features could effectively distinguish the scoliosis severity with 85.7% accuracy. When the measured features are ranked in order of high contribution, the abduction and adduction of left hip joint in the single support phase is most important in gait of patients with scoliosis. These results demonstrate considerable potential in applying SVMs in gait classification for medical applications.
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- 2018
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25. Effect of germination and water absorption on scarification and stratification of kousa dogwood seed
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Ju Sung Cho and Cheol Hee Lee
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0106 biological sciences ,biology ,Chemistry ,Seed dormancy ,Plant physiology ,Plant Science ,Horticulture ,Cornus kousa ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Stratification (seeds) ,Germination ,Dormancy ,Water content ,Scarification ,010606 plant biology & botany ,Biotechnology - Abstract
Cornus kousa (kousa dogwood), used as a landscape tree and a source of food and medicine, is difficult to propagate from seeds owing to dormancy. The present study was conducted to develop an effective method of seed propagation and identify the seed dormancy type. Kousa dogwood seeds were classified as presenting physical dormancy (PY) and physiological dormancy (PD) from an immature embryo. Seeds were contained within an impermeable endocarp that conferred PY and had an undifferentiated embryo that grew and differentiated after scarification and cold moist stratification, leading to improved germination. To break PY + PD, four replicates of 50 seeds (3200 in total) for each treatment were prepared by scarification and cold moist stratification. These methods combined improved moisture absorption and germination more than either treatment alone. In particular, the addition of cold moist stratification treatment to scarified seeds could effectively induce embryo development. By contrast, untreated seeds showed low germination rate of less than 1% at 30 °C with continuous light. Sulfuric acid (H2SO4) at different concentrations and durations was used to uniformly wound the endocarp of seeds. Treatment with 80% H2SO4 for 10 min resulted in the highest germination rate (68.6%) and moisture content (65.7%), which were higher than those following polishing with a brushing machine for 5–40 min. Longer treatment with high concentrations of H2SO4 (80 and 100%) caused the acid to infiltrate the seed and inhibit germination by damaging internal tissues, while low concentrations (40 and 60%) did not affect germination rates even after treatment for more than 10 min. To obtain maximum germination, concentration and treatment duration of sulfuric acid should be carefully controlled.
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- 2018
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26. Author Correction: A comprehensive metabolic map for production of bio-based chemicals
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Hyun Uk Kim, Woo Dae Jang, Dong In Kim, Sang Yup Lee, Jae Ho Shin, Yu-Sin Jang, Tong Un Chae, Jae Sung Cho, Je Woong Kim, and Yoo-Sung Ko
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Engineering ,business.industry ,Process Chemistry and Technology ,Production (economics) ,Bio based ,Bioengineering ,Biochemical engineering ,business ,Biochemistry ,Catalysis - Published
- 2019
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27. Development of thermophysical calculator for stainless steel casting alloys by using CALPHAD approach
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K. D. Savelyev, In-Sung Cho, and V. M. Golod
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thermophysical properties ,Materials science ,stainless steels ,Alloy ,casting simulation ,chemistry.chemical_element ,Mechanical engineering ,02 engineering and technology ,engineering.material ,lcsh:Technology ,01 natural sciences ,Heat capacity ,symbols.namesake ,Aluminium ,lcsh:Manufactures ,Latent heat ,0103 physical sciences ,Materials Chemistry ,CALPHAD ,Steel casting ,010302 applied physics ,lcsh:T ,Metallurgy ,Metals and Alloys ,021001 nanoscience & nanotechnology ,Casting ,Gibbs free energy ,chemistry ,symbols ,engineering ,0210 nano-technology ,lcsh:TS1-2301 - Abstract
The calculation of thermophysical properties of stainless steel castings and its application to casting simulation is discussed. It is considered that accurate thermophysical properties of the casting alloys are necessary for the valid simulation of the casting processes. Although previous thermophysical calculation software requires a specific knowledge of thermodynamics, the calculation method proposed in the present study does not require any special knowledge of thermodynamics, but only the information of compositions of the alloy. The proposed calculator is based on the CALPHAD approach for modeling of multi-component alloys, especially in stainless steels. The calculator proposed in the present study can calculate thermophysical properties of eight-component systems on an iron base alloy (Fe-C-Si-Cr-Mn-Ni-Cu-Mo), and several Korean standard stainless steel alloys were calculated and discussed. The calculator can evaluate the thermophysical properties of the alloys such as density, heat capacity, enthalpy, latent heat, etc, based on full Gibbs energy for each phase. It is expected the proposed method can help casting experts to devise the casting design and its process easily in the field of not only stainless steels but also other alloy systems such as aluminum, copper, zinc, etc.
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- 2017
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28. Raptor genomes reveal evolutionary signatures of predatory and nocturnal lifestyles
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Yun Sung Cho, Soonok Kim, Jinho Jang, Oksung Chung, Jessica A. Weber, Jérôme Fuchs, Christopher C. Witt, Hee-Jong Kim, Jeremy S. Edwards, Andrea Manica, Jung A Kim, Seung Gu Park, Joo-Hong Yeo, Jong Bhak, Seung-Gu Kang, Ki-Jeong Na, Hak-Min Kim, Je Hoon Jun, Sung Hyun Kim, Hwang-Yeol Lee, David P. Mindell, Jeong-Ho Kim, Jin-Young Park, Hwa-Jung Kim, Bhak, Jong [0000-0002-4228-1299], and Apollo - University of Cambridge Repository
- Subjects
Otus sunia ,lcsh:QH426-470 ,Zoology ,Kestrel ,Nocturnal ,Evolutionary adaptation ,Falco tinnunculus ,Predation ,Nocturnality ,03 medical and health sciences ,0302 clinical medicine ,biology.animal ,De novo assembly ,Animals ,lcsh:QH301-705.5 ,Phylogeny ,030304 developmental biology ,0303 health sciences ,Genome ,biology ,Raptors ,Research ,Comparative genomics ,Scops owl ,biology.organism_classification ,Predatory lifestyle ,Adaptation, Physiological ,Biological Evolution ,Raptor ,Circadian Rhythm ,Buzzard ,lcsh:Genetics ,Strigiformes ,lcsh:Biology (General) ,Predatory Behavior ,Accipitriformes ,030217 neurology & neurosurgery - Abstract
BackgroundBirds of prey (raptors) are dominant apex predators in terrestrial communities, with hawks (Accipitriformes) and falcons (Falconiformes) hunting by day, and owls (Strigiformes) hunting by night.ResultsHere, we report new genomes and transcriptomes for 20 species of birds, including 16 species of birds of prey, and high-quality reference genomes for the Eurasian eagle-owl (Bubo bubo), oriental scops-owl (Otus sunia), eastern buzzard (Buteo japonicus), and common kestrel (Falco tinnunculus). Our extensive genomic analysis and comparisons with non-raptor genomes identified common molecular signatures that underpin anatomical structure and sensory, muscle, circulatory, and respiratory systems related to a predatory lifestyle. Compared with diurnal birds, owls exhibit striking adaptations to the nocturnal environment, including functional trade-offs in the sensory systems (e.g., loss of color vision genes and selection for enhancement of nocturnal vision and other sensory systems) that are probably convergent with other nocturnal avian orders. Additionally, we found that a suite of genes associated with vision and circadian rhythm were differentially expressed between nocturnal and diurnal raptors, indicating adaptive expression change during the transition to nocturnality.ConclusionsOverall, raptor genomes showed genomic signatures associated with the origin and maintenance of several specialized physiological and morphological features essential to be apex predators.
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- 2019
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29. The genome of the giant Nomura’s jellyfish sheds light on the early evolution of active predation
- Author
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Jae-Chun Ryu, Jung-Hyun Lee, Nayun Lee, Seung Gu Park, Hyung-Soon Yim, Kyoungsoon Shin, Andrea Manica, Jessica A. Weber, Youngjune Bhak, Yeonsu Jeon, Ok Sung Chung, Yun Sung Cho, Marc W. Kirschner, Seungshic Yum, Victor Luria, Sungwon Jeon, Yejin Jo, Seonock Woo, Nayoung Lee, Amir Karger, Jeremy S. Edwards, Jong Bhak, Hak-Min Kim, Manica, Andrea [0000-0003-1895-450X], and Apollo - University of Cambridge Repository
- Subjects
Nomura's jellyfish ,Jellyfish ,Scyphozoa ,Physiology ,Venom ,Jellyfish mobility ,Plant Science ,Genome ,General Biochemistry, Genetics and Molecular Biology ,Evolution, Molecular ,03 medical and health sciences ,0302 clinical medicine ,Structural Biology ,biology.animal ,Animals ,Gene family ,14. Life underwater ,Hox gene ,lcsh:QH301-705.5 ,Phylogeny ,Ecology, Evolution, Behavior and Systematics ,030304 developmental biology ,0303 health sciences ,Medusa structure formation ,biology ,Cell Biology ,de novo genome assembly ,biology.organism_classification ,Biological Evolution ,Body plan ,lcsh:Biology (General) ,Evolutionary biology ,Predatory Behavior ,General Agricultural and Biological Sciences ,030217 neurology & neurosurgery ,Research Article ,Developmental Biology ,Biotechnology - Abstract
Background Unique among cnidarians, jellyfish have remarkable morphological and biochemical innovations that allow them to actively hunt in the water column and were some of the first animals to become free-swimming. The class Scyphozoa, or true jellyfish, are characterized by a predominant medusa life-stage consisting of a bell and venomous tentacles used for hunting and defense, as well as using pulsed jet propulsion for mobility. Here, we present the genome of the giant Nomura’s jellyfish (Nemopilema nomurai) to understand the genetic basis of these key innovations. Results We sequenced the genome and transcriptomes of the bell and tentacles of the giant Nomura’s jellyfish as well as transcriptomes across tissues and developmental stages of the Sanderia malayensis jellyfish. Analyses of the Nemopilema and other cnidarian genomes revealed adaptations associated with swimming, marked by codon bias in muscle contraction and expansion of neurotransmitter genes, along with expanded Myosin type II family and venom domains, possibly contributing to jellyfish mobility and active predation. We also identified gene family expansions of Wnt and posterior Hox genes and discovered the important role of retinoic acid signaling in this ancient lineage of metazoans, which together may be related to the unique jellyfish body plan (medusa formation). Conclusions Taken together, the Nemopilema jellyfish genome and transcriptomes genetically confirm their unique morphological and physiological traits, which may have contributed to the success of jellyfish as early multi-cellular predators. Electronic supplementary material The online version of this article (10.1186/s12915-019-0643-7) contains supplementary material, which is available to authorized users.
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- 2019
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30. Structural basis of ECF-σ-factor-dependent transcription initiation
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David Degen, Sukhendu Mandal, Kalyan Das, Yu Feng, Wei Lin, Min Sung Cho, and Richard H. Ebright
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DNA, Bacterial ,Models, Molecular ,0301 basic medicine ,Transcription, Genetic ,Science ,General Physics and Astronomy ,Sigma Factor ,Computational biology ,02 engineering and technology ,Crystallography, X-Ray ,Article ,General Biochemistry, Genetics and Molecular Biology ,Transcription initiation ,03 medical and health sciences ,chemistry.chemical_compound ,Protein structure ,Bacterial Proteins ,Transcription (biology) ,Sigma factor ,RNA polymerase ,Protein Interaction Domains and Motifs ,Binding site ,Promoter Regions, Genetic ,lcsh:Science ,030304 developmental biology ,Regulation of gene expression ,0303 health sciences ,Binding Sites ,Multidisciplinary ,030306 microbiology ,Sigma ,Promoter ,DNA-Directed RNA Polymerases ,Gene Expression Regulation, Bacterial ,Mycobacterium tuberculosis ,General Chemistry ,021001 nanoscience & nanotechnology ,Protein Structure, Tertiary ,3. Good health ,Cell biology ,DNA-Binding Proteins ,030104 developmental biology ,chemistry ,lcsh:Q ,0210 nano-technology ,DNA - Abstract
Extracytoplasmic (ECF) σ factors, the largest class of alternative σ factors, are related to primary σ factors, but have simpler structures, comprising only two of six conserved functional modules in primary σ factors: region 2 (σR2) and region 4 (σR4). Here, we report crystal structures of transcription initiation complexes containing Mycobacterium tuberculosis RNA polymerase (RNAP), M. tuberculosis ECF σ factor σL, and promoter DNA. The structures show that σR2 and σR4 of the ECF σ factor occupy the same sites on RNAP as in primary σ factors, show that the connector between σR2 and σR4 of the ECF σ factor–although shorter and unrelated in sequence–follows the same path through RNAP as in primary σ factors, and show that the ECF σ factor uses the same strategy to bind and unwind promoter DNA as primary σ factors. The results define protein-protein and protein-DNA interactions involved in ECF-σ-factor-dependent transcription initiation., No structural data have been available for RNA polymerase holoenzymes or transcription initiation complexes that contain extracytoplasmic σ factors. Here the authors report the crystal structures of transcription initiation complexes comprising Mycobacterium tuberculosis RNA polymerase, extracytoplasmic σ factor σL and promoter DNA.
- Published
- 2019
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31. Publisher Correction: Filling metal–organic framework mesopores with TiO2 for CO2 photoreduction
- Author
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Jun Cheng, Jie Wu, Ling Zan, Mei Jia, Osamu Terasaki, Yi Zhou, Hae Sung Cho, Peter Oleynikov, Yanhang Ma, Tianyou Peng, Hexiang Deng, Xiaohui Xu, Zhuo Jiang, Deng Ding, and Chao Wang
- Subjects
Multidisciplinary ,Materials science ,Chemical engineering ,Metal-organic framework ,Mesoporous material - Published
- 2021
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32. A comparative study on multi-class SVM & kernel function for land cover classification in a KOMPSAT-2 image
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Narangerel Gantulga, Yun-Woong Choi, and Gi-Sung Cho
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Structured support vector machine ,business.industry ,0211 other engineering and technologies ,Pattern recognition ,Linear classifier ,02 engineering and technology ,Quadratic classifier ,Machine learning ,computer.software_genre ,Multiclass classification ,Support vector machine ,ComputingMethodologies_PATTERNRECOGNITION ,Radial basis function kernel ,Least squares support vector machine ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Artificial intelligence ,Tree kernel ,business ,computer ,021101 geological & geomatics engineering ,Civil and Structural Engineering ,Mathematics - Abstract
Recently, number of studies delved into the application of Support Vector Machine (SVM) which is used in various fields to remote sensing has been rapidly increasing. The SVM was originally designed for purposes of binary classification and thus it needs to be extended to be applied to the multi-class classification. However, the SVM multi-class classifier extended for this purpose, may accompany problems in selecting items for the classification with varying accuracy of the results of classification to be depending upon classifiers and kernel functions to be employed for. Therefore, general criteria to select applicable algorithm are also needed for the practical application of the results of such multi-class classification. This study was designed to compare and find the most suitable multi-class classifier for the satellite land cover image classification in a high resolution KOMPSAT 2 image around the Expo-Science Park placed in Yuseong-gu, South Korea. The results of the study found the multi-class classifier of Crammer and Singer appeared to be superior to other classifiers in the study area. And results of the application of 4 kernel functions to such multiclass classifiers revealed the best performance of the RBF kernel function followed by those of the Polynomial and Linear ones while the Sigmoid function was lagging behind other ones.
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- 2016
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33. Prognostic value of the Glasgow Prognostic Score in renal cell carcinoma: a meta-analysis
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Dae Sung Cho, Se Joong Kim, Sung Ryul Shim, and Sun Il Kim
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Oncology ,medicine.medical_specialty ,Urology ,030232 urology & nephrology ,Subgroup analysis ,Nephrectomy ,Disease-Free Survival ,03 medical and health sciences ,0302 clinical medicine ,Renal cell carcinoma ,Internal medicine ,medicine ,Humans ,Carcinoma, Renal Cell ,Serum Albumin ,Proportional Hazards Models ,business.industry ,Hazard ratio ,Odds ratio ,Prognosis ,medicine.disease ,Kidney Neoplasms ,Confidence interval ,Survival Rate ,C-Reactive Protein ,Sample size determination ,030220 oncology & carcinogenesis ,Meta-analysis ,Neoplasm Recurrence, Local ,business ,Hypoalbuminemia ,Cohort study - Abstract
Glasgow Prognostic Score (GPS) has been reported to predict oncologic outcomes in various type of cancer. However, their prognostic value in patients with renal cell carcinoma (RCC) is unclear. In this meta-analysis, we evaluated the prognostic significance of GPS in RCC patients. We performed comprehensive searches of electronic databases to identify studies that evaluated the prognostic impact of pretreatment GPS in RCC patients. The end points were cancer-specific survival (CSS), recurrence-free/disease-free survival (RFS/DFS). Meta-analysis using random-effects models was performed to calculate hazard ratios (HRs) or odds ratios with 95 % confidence intervals (CIs). Nine retrospective, observational, cohort studies involving 2096 patients were included. Seven studies evaluated CSS, and three evaluated RFS. Our results showed that higher GPS (0 vs. 1 vs. 2) was significantly predictive of poorer CSS (HR 3.68, 95 % CI 2.52–5.40, p
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- 2016
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34. Graphene Electrode Enabling Electrochromic Approaches for Daylight-Dimming Applications
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Yong-Hae Kim, Seungmin Cho, Joo Yeon Kim, Chi-Sun Hwang, Jeong-Ik Lee, Chil Seong Ah, Nam Sung Cho, Tae-Youb Kim, Sujung Kim, Sang-Hoon Cheon, Ji-Young Oh, Seong M. Cho, Seung-Youl Kang, Hojun Ryu, Kisoo Kim, and Kyuwon Kim
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Fabrication ,Materials science ,Oxide ,lcsh:Medicine ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,Electrochromic devices ,01 natural sciences ,Article ,law.invention ,chemistry.chemical_compound ,PEDOT:PSS ,law ,lcsh:Science ,Multidisciplinary ,business.industry ,Graphene ,lcsh:R ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,chemistry ,Electrochromism ,Electrode ,Optoelectronics ,lcsh:Q ,0210 nano-technology ,business ,Indium - Abstract
For environmental reason, buildings increasingly install smart windows, which can dim incoming daylight based on active electrochromic devices (ECDs). In this work, multi-layered graphene (MLG) was investigated as an ECD window electrode, to minimize carbon dioxide (CO2) emissions by decreasing the electricity consumption for building space cooling and heating and as an alternative to the transparent conductor tin-doped indium oxide (ITO) in order to decrease dependence on it. Various MLG electrodes with different numbers of graphene layers were prepared with environmentally friendly poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonate) (PEDOT:PSS) to produce ECD cells. Tests demonstrated the reproducibility and uniformity in optical performance, as well as the flexibility of the ECD fabrication. With the optimized MLG electrode, the ECD cells exhibited a very fast switching response for optical changes from transparent to dark states of a few hundred msec.
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- 2018
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35. Comparative study of fecal microbiota in patients with type II diabetes after consumption of apple juice for 4 weeks
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Achim Bub, Stephanie N. Seifert, Gyu-Sung Cho, Alexander Hanak, Charles M. A. P. Franz, Alexander Röth, Anja König, Melanie Huch, and Bernhard Watzl
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Firmicutes ,fungi ,Bacteroidetes ,biochemical phenomena, metabolism, and nutrition ,Biology ,Fecal microbiota ,equipment and supplies ,biology.organism_classification ,Applied Microbiology and Biotechnology ,Bacterial counts ,Type ii diabetes ,fluids and secretions ,bacteria ,Profile analysis ,In patient ,Food science ,Bacteria ,Food Science ,Biotechnology - Abstract
The effect of cloudy apple juice on fecal microbiota of type 2 diabetics was studied. Five volunteers consumed apple juice while 5 control volunteers received an isocaloric control beverage daily for 4 weeks. DGGE profile analysis showed high diversity between volunteers that did not change over the intervention period using primers for Firmicutes, Bacteroidetes, bifidobacteria, enterococci, and enterobacteria. An exception was observed using lactobacilli primers, perhaps as the result of the dietary influence. Consumption of apple juice was not correlated with changes in DGGE profiles. Quantitative PCR was used to investigate the effect of apple juice on bacterial counts in different subgroups. Apple juice did not lead to significantly (p>0.05) different numbers of total bacteria, enterobacteria, bifidobacteria, lactobacilli, or Bacteroidetes, but caused a significant (p
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- 2015
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36. Extra adsorption and adsorbate superlattice formation in metal-organic frameworks
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Minhyung Cho, Zhiyue Dong, Osamu Terasaki, Keiichi Miyasaka, Alexander V. Neimark, Jeung Ku Kang, Hexiang Deng, Omar M. Yaghi, and Hae Sung Cho
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Multidisciplinary ,Adsorption ,Hydrogen ,Capillary condensation ,Chemistry ,Chemical physics ,Superlattice ,Molecule ,chemistry.chemical_element ,Nanotechnology ,Metal-organic framework ,Mesoporous material ,Porosity - Abstract
Metal-organic frameworks (MOFs) have a high internal surface area and widely tunable composition, which make them useful for applications involving adsorption, such as hydrogen, methane or carbon dioxide storage. The selectivity and uptake capacity of the adsorption process are determined by interactions involving the adsorbates and their porous host materials. But, although the interactions of adsorbate molecules with the internal MOF surface and also amongst themselves within individual pores have been extensively studied, adsorbate-adsorbate interactions across pore walls have not been explored. Here we show that local strain in the MOF, induced by pore filling, can give rise to collective and long-range adsorbate-adsorbate interactions and the formation of adsorbate superlattices that extend beyond an original MOF unit cell. Specifically, we use in situ small-angle X-ray scattering to track and map the distribution and ordering of adsorbate molecules in five members of the mesoporous MOF-74 series along entire adsorption-desorption isotherms. We find in all cases that the capillary condensation that fills the pores gives rise to the formation of 'extra adsorption domains'-that is, domains spanning several neighbouring pores, which have a higher adsorbate density than non-domain pores. In the case of one MOF, IRMOF-74-V-hex, these domains form a superlattice structure that is difficult to reconcile with the prevailing view of pore-filling as a stochastic process. The visualization of the adsorption process provided by our data, with clear evidence for initial adsorbate aggregation in distinct domains and ordering before an even distribution is finally reached, should help to improve our understanding of this process and may thereby improve our ability to exploit it practically.
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- 2015
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37. A study on flow control valve characteristics in an oil hydraulic vane pump for power steering systems
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Jae Youn Jung and Ihn Sung Cho
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Engineering ,business.product_category ,business.industry ,Mechanical Engineering ,Mechanical engineering ,Progressive cavity pump ,Steering wheel ,Flow control valve ,Pulley ,law.invention ,Flow control (fluid) ,Mechanics of Materials ,Control theory ,law ,Actuator ,business ,Power steering ,Variable displacement pump - Abstract
In the power steering system of an automobile, the balanced and fixed displacement type vane pump is principally applied to the main power source. It is driven by a pulley that is attached to the shaft of the vehicle's engine, and the pulley ratio is about 1:1. The vane pump continuously discharges an outlet flow rate proportional to the rotating speed of the engine. In a vane pump without the flow control valve, an increase in the discharge flow rate means a linear increase in the actuator speed. At high speed when the driver rotates the steering wheel by even a small amount, there is a high risk of an accident due to the quick rotation of the tire joined to the actuator and links. We designed a flow control valve of the fixed displacement and pressure balanced type vane pump for power steering is designed and simulated using AMESim software. Its theoretical flow characteristics with respect to the rotating speed of the engine are compared and validated with experimental data. The results show that the design parameters, such as the flow area, the underlap length, the spool clearance, the main spring stiffness and the spring initial force, largely affect the flow control characteristics.
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- 2015
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38. A study on the optimum design for the valve plate of a swash plate-type oil hydraulic piston pump
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Ihn Sung Cho
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Engineering ,business.industry ,Mechanical Engineering ,Axial piston pump ,Structural engineering ,Tribology ,Finite element method ,Stress (mechanics) ,Hydraulic cylinder ,Mechanics of Materials ,Hydraulic machinery ,Orthogonal array ,business ,Variable displacement pump - Abstract
Numerous studies have been conducted on hydraulic systems operating under high pressure. However, such systems are difficult to realize because of mechanical limitations as a result of tribological problems between relative sliding parts. Design techniques, manufacturing techniques, and tribological characteristics must be improved or innovated to operate such systems under increased pressure. The stress distributions and optimum design factors needed to satisfy these requirements under maximum pressure are determined by analyzing the stress on the valve plate of a hydraulic axial piston pump. This pump is among the most important relative sliding parts. As per the result of the analysis conducted using an orthogonal array, the extent of the influence of the design factors on maximum stress value is ordered as follows: [z > M > h > r]. Moreover, the maximum stress value of the optimum model is 13.3% lower than that of the standard model. Results also show that the stress characteristic of the optimum model is more stable than that of the standard model.
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- 2015
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39. The influence of boundary conditions on the lubrication characteristics of a journal bearing for reciprocating compressors
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Ihn Sung Cho
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Crankshaft ,Engineering ,Reciprocating compressor ,Bearing (mechanical) ,business.industry ,Mechanical Engineering ,Mechanical engineering ,Refrigeration ,Seasonal energy efficiency ratio ,law.invention ,Mechanics of Materials ,law ,Air conditioning ,Lubrication ,Boundary value problem ,business - Abstract
The performance of a reciprocating compressor in refrigeration and air-conditioning systems is influenced by the lubrication characteristics of the critical sliding components. Improvements in design and performance of reciprocating compressors therefore depend in part upon the lubrication characteristics between the crankshaft and journal bearing. Current studies have explored experimental and theoretical methods, yet difficulties arise when applying these results to practical designs in the field. The present study seeks to enhance the energy efficiency ratio, and to improve the reliability of the reciprocating compressor for refrigeration and air conditioning systems by studying the influence of boundary conditions on the lubrication characteristics between the crankshaft and journal bearing. The results demonstrate that appropriate boundary conditions, when applied to theoretical analysis, improve both the speed and ease of the design process.
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- 2015
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40. Chicken (Gallus gallus) endogenous retrovirus generates genomic variations in the chicken genome
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Jinmin Lee, Kyudong Han, Dong-Yep Oh, Seyoung Mun, Chun-Sung Cho, and Dong Hee Kim
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0301 basic medicine ,Genetics ,Transposable element ,animal structures ,030102 biochemistry & molecular biology ,Phylogenetic tree ,Retrotransposon ,Full-length GGERV10 ,Genomic variation ,Molecularmarker ,Incomplete lineage sorting ,Endogenous retrovirus ,Locus (genetics) ,Biology ,Genome ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,chemistry ,Molecular marker ,embryonic structures ,Molecular Biology ,Reference genome - Abstract
Background: Transposable elements (TEs) comprise similar to 10% of the chicken (Gallus gallus) genome. The content of TEs is much lower than that of mammalian genomes, where TEs comprise around half of the genome. Endogenous retroviruses are responsible for similar to 1.3% of the chicken genome. Among them is Gallus gallus endogenous retrovirus 10 (GGERV10), one of the youngest endogenous retrovirus families, which emerged in the chicken genome around 3 million years ago. Results: We identified a total of 593 GGERV10 elements in the chicken reference genome using UCSC genome database and RepeatMasker. While most of the elements were truncated, 49 GGERV10 elements were full-length retaining 5' and 3' LTRs. We examined in detail their structural features, chromosomal distribution, genomic environment, and phylogenetic relationships. We compared LTR sequence among five different GGERV10 subfamilies and found sequence variations among the LTRs. Using a traditional PCR assay, we examined a polymorphism rate of the 49 full-length GGERV10 elements in three different chicken populations of the Korean domestic chicken, Leghorn, and Araucana. The result found a breed-specific GGERV10B insertion locus in the Korean domestic chicken, which could be used as a Korean domestic chicken-specific marker. Conclusions: GGERV10 family is the youngest ERV family and thus might have contributed to recent genomic variations in different chicken populations. The result of this study showed that one of GGERV10 elements integrated into the chicken genome after the divergence of Korean domestic chicken from other closely related chicken populations, suggesting that GGERV10 could be served as a molecular marker for chicken breed identification.
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- 2017
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41. Influence of a probiotic Lactobacillus casei strain on the colonisation with potential pathogenic streptococci and Staphylococcus aureus in the nasopharyngeal space of healthy men with a low baseline NK cell activity
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Melanie Huch, Charles M. A. P. Franz, Stephanie N. Seifert, Achim Bub, Jeannette Kramlich, Bernhard Watzl, and Gyu-Sung Cho
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Adult ,DNA, Bacterial ,Male ,Microbiology (medical) ,Staphylococcus aureus ,Saliva ,Lactobacillus casei ,Adolescent ,Immunology ,medicine.disease_cause ,DNA, Ribosomal ,law.invention ,Microbiology ,Placebos ,Young Adult ,Probiotic ,fluids and secretions ,law ,Nasopharynx ,RNA, Ribosomal, 16S ,Streptococcus pneumoniae ,medicine ,Humans ,Immunology and Allergy ,Bacteriological Techniques ,integumentary system ,biology ,Streptococcus ,Probiotics ,Pharynx ,food and beverages ,Sequence Analysis, DNA ,General Medicine ,Middle Aged ,biology.organism_classification ,Healthy Volunteers ,Killer Cells, Natural ,Lacticaseibacillus casei ,Treatment Outcome ,medicine.anatomical_structure ,Immunoglobulin A, Secretory ,Staphylococcus - Abstract
The effect of a daily intake of the probiotic strain Lactobacillus casei Shirota (LcS) on the colonisation of pathogens, specifically streptococci and Staphylococcus aureus, in the nose and throat of healthy human volunteers with low natural killer cell activity, was investigated in a randomised and controlled intervention study. The study consisted of a 2-week run-in phase, followed by a 4-week intervention phase. The probiotic treatment group received a fermented milk drink with LcS, while the placebo group received an equally composed milk drink without the probiotic additive. To isolate potential pathogenic streptococci and Staph. aureus, samples from the pharynx, as well as of both middle nasal meati, were taken, once after the run-in phase and once at the end of the intervention phase. Isolated bacteria were identified as either Staph. aureus and α- or β-haemolytic streptococci in a polyphasic taxonomical approach based on phenotypic tests, amplified ribosomal DNA restriction analysis genotyping, and 16S rRNA gene sequencing of representative strains. Salivary secretory immunoglobulin A (SIgA) was used as marker of protective mucosal immunity to evaluate whether LcS treatment influenced SIgA production. No statistically significant effect could be determined for intervention with LcS on the incidence of Staph. aureus in the nasal space, Staph. aureus in the pharyngeal space or for β-haemolytic streptococci and Streptococcus pneumoniae in the pharyngeal space. Thus, the intervention did not influence the nasopharyngeal colonisation with Gram-positive potential pathogens. Production of salivary SIgA as a potential means of microbiota modulation was also not affected.
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- 2014
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42. The friction characteristics of the journal bearing in a reciprocating compressor for refrigeration and air conditioning systems
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Ihn Sung Cho and Jae Youn Jung
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Crankshaft ,Engineering ,Bearing (mechanical) ,Reciprocating compressor ,business.industry ,Mechanical Engineering ,Mechanical engineering ,Refrigeration ,Seasonal energy efficiency ratio ,Automotive engineering ,law.invention ,Mechanics of Materials ,law ,Power consumption ,Air conditioning ,Lubrication ,business - Abstract
The performance of a reciprocating compressor in refrigeration and air-conditioning systems is influenced by the lubrication characteristics of the critical sliding components. Thus, the lubrication characteristics between the crankshaft and journal bearing have to be researched in order to improve the design and performance of a reciprocating compressor. Therefore, in this study, to enhance the EER (energy efficiency ratio) to reduce power consumption, and to improve the reliability of a reciprocating compressor for refrigeration and air conditioning systems, theoretical analysis of the friction characteristics between the crankshaft and journal bearing in a reciprocating compressor is studied. The results demonstrate that frictional characteristics are significantly influenced by the clearance between the crankshaft and journal bearing and the viscosity of the lubricating oil.
- Published
- 2014
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43. A study on the pressure ripple characteristics in a bent-axis type oil hydraulic piston pump
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Ihn-Sung Cho and Jae-Youn Jung
- Subjects
Engineering ,Piston pump ,business.industry ,Mechanical Engineering ,Radial piston pump ,Axial piston pump ,Physics::Optics ,Reciprocating pump ,Mechanical engineering ,Progressive cavity pump ,Mechanics ,Physics::Classical Physics ,law.invention ,Piston ,Mechanics of Materials ,law ,Condensed Matter::Statistical Mechanics ,Plunger pump ,business ,Variable displacement pump - Abstract
To improve the performance of a bent-axis type axial piston pump driven by tapered pistons, it is necessary to know the pressure ripple characteristics. The purpose of this paper is to understand the effect on the pressure ripple characteristics, and to predict by comparing experimental and theoretical analysis results. The simulation model of a bent-axis type axial piston pump is developed in the AMESim environment using the geometrical dimension, and the driving mechanism of the piston pump, such as the stroke of pump, the velocity of piston, the instantaneous volumetric flow, the overlap area of valve plate opening to cylinder bore, the angle of notch, and so on. The results show that theoretical analysis results of the bent-axis type axial piston pump by using the AMESim approximate the pressure ripple characteristic of the test pump, and through this, simulations can be obtained that predict the performance characteristics of a bentaxis type axial piston pump.
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- 2013
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44. An ethnically relevant consensus Korean reference genome is a step towards personal reference genomes
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Byung Chul Kim, Kyun Shik Chae, George M. Church, Je Hoon Jun, Yun Sung Cho, Hyunho Kim, Andrea Manica, Tae-Kwang Oh, Semin Lee, Jeremy S. Edwards, Sungwoong Jho, Jong Bhak, Chang Geun Kim, Yong-Joo Lee, Hak-Min Kim, Sangsoo Kim, Anders Eriksson, Eriksson, Anders [0000-0003-3436-3726], Manica, Andrea [0000-0003-1895-450X], and Apollo - University of Cambridge Repository
- Subjects
0301 basic medicine ,Consensus ,Science ,Population ,General Physics and Astronomy ,Computational biology ,Biology ,Genome ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,0302 clinical medicine ,Asian People ,Republic of Korea ,Humans ,education ,Genetics ,education.field_of_study ,Multidisciplinary ,Genome, Human ,Chromosome Mapping ,High-Throughput Nucleotide Sequencing ,Sequence Analysis, DNA ,General Chemistry ,Genome project ,Personal Genome Project ,030104 developmental biology ,Variome ,Human genome ,030217 neurology & neurosurgery ,Personal genomics ,Reference genome - Abstract
Human genomes are routinely compared against a universal reference. However, this strategy could miss population-specific and personal genomic variations, which may be detected more efficiently using an ethnically relevant or personal reference. Here we report a hybrid assembly of a Korean reference genome (KOREF) for constructing personal and ethnic references by combining sequencing and mapping methods. We also build its consensus variome reference, providing information on millions of variants from 40 additional ethnically homogeneous genomes from the Korean Personal Genome Project. We find that the ethnically relevant consensus reference can be beneficial for efficient variant detection. Systematic comparison of human assemblies shows the importance of assembly quality, suggesting the necessity of new technologies to comprehensively map ethnic and personal genomic structure variations. In the era of large-scale population genome projects, the leveraging of ethnicity-specific genome assemblies as well as the human reference genome will accelerate mapping all human genome diversity. The utility of a universal reference sequence for human genome comparisons is dependent on the ethnic origins of the individuals being sequenced. Here the authors report a Korean reference genome and consensus variome, and show that an ethnically-relevant reference can improve variant detection.
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- 2016
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45. Association of Glutathione S-transferase genes (GSTM1 and GSTT1) polymorphisms with hypertension in lead-exposed workers
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Soojeong Lee, Nam-Soo Kim, Hak-Jae Kim, Kwang Sung Cho, Jae Soon Joo, and Byung Kook Lee
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Genetics ,medicine.medical_specialty ,Health, Toxicology and Mutagenesis ,Intracellular glutathione ,Public Health, Environmental and Occupational Health ,Glutathione ,Biology ,Toxicology ,Essential hypertension ,medicine.disease ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,Endocrinology ,Glutathione S-transferase ,Positive type ,chemistry ,Internal medicine ,Multiplex polymerase chain reaction ,medicine ,biology.protein ,General Pharmacology, Toxicology and Pharmaceutics ,Allele ,Gene - Abstract
It is proposed that lead concentrations in the blood are related to intracellular glutathione and lead might be conjugated with glutathione non-enzymatically or enzymatically via glutathione S-transferase (GST). Essential hypertension is a complex, multifactorial and polygenic disease in which the underlying genetic components remain unknown. This study was aimed to investigate GST-mu1 (GSTM1) and GST-theta1 (GSTT1) gene polymorphisms in lead-exposed workers and their relationship with blood lead levels and leadrelated hypertension. To address the possible association, GSTM1 and GSTT1 (homozygous deletion vs. non-deleted) polymorphisms in 755 lead-exposed male workers were analyzed. GSTM1 and GSTT1 polymorphisms were determined using a Multiplex PCR. We observed significant association in positive alleles of GSTT1 (OR=1.593, 95% CI=1.157–2.194). However, no significant association in GSTM1 was observed with lead-related hypertension. For combined analysis with GSTM1 and GSTT1, both positive type (+/+) and GSTT1 positive (−/+) group showed significant differences between groups. These data suggest that the GSTT1 positive type polymorphism might be associated with lead-related hypertension in the lead-exposed male workers.
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- 2012
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46. Characterization of Putative Adhesion Genes in the Potentially Probiotic Strain Lactobacillus plantarum BFE 5092
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Annika Dorn, Melanie Huch, Charles M. A. P. Franz, Gyu-Sung Cho, Alexander Hanak, and Annabelle Grimm
- Subjects
chemistry.chemical_classification ,Signal peptide ,Growth medium ,biology ,biology.organism_classification ,Microbiology ,Amino acid ,chemistry.chemical_compound ,chemistry ,Biochemistry ,Molecular Medicine ,Peptidoglycan ,Molecular Biology ,Peptide sequence ,Gene ,Lactobacillus plantarum ,Bacteria - Abstract
Two putative adhesion genes of the potentially probiotic strain Lactobacillus plantarum BFE 5092, i.e., a gene with similarity to an aggregation-promoting factor gene apf5092, and the mucin-binding protein gene mub5092, were investigated in this study. The gene encoding apf5092 encoded a protein bearing a predicted 26 amino acid signal peptide and a LysM domain putatively involved in binding to peptidoglycan. Moreover, the deduced protein also showed an amino acid sequence characteristic of an aggregation-promoting factor. The genes were tested for expression under different environmental conditions, and transcriptional studies on apf5092 showed that the expression could be influenced by low temperature and pH within 30 min. The aggregation behavior of the cells also changed at the low pH condition, but less noticeably at low temperature. To further investigate the role of apf5092 in aggregation, it was cloned and expressed in E. coli. The transformed strain showed higher co-aggregation ability with Gram-positive bacteria. Transcription studies on mub5092 revealed that it could be induced by mucin when added to the growth medium within 30 min. The data suggested that L. plantarum BFE 5092 can quickly adapt to changing environmental conditions and that enhanced aggregation may be important to survive low pH conditions, e.g., of the stomach or of fermented foods, and may thus be an important colonization factor.
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- 2011
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47. Synthesis of poly(ethylene glycol)-b-poly(mercapto ethylacrylamide) diblock copolymer via atom transfer radical polymerization
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Aleya Hasneen, In-sung Cho, Hyun-jong Paik, and Keon-Woo Kim
- Subjects
chemistry.chemical_classification ,Materials science ,Polymers and Plastics ,Reducing agent ,Atom-transfer radical-polymerization ,technology, industry, and agriculture ,General Chemistry ,Polymer ,Condensed Matter Physics ,Gel permeation chromatography ,chemistry.chemical_compound ,Monomer ,chemistry ,Polymer chemistry ,Materials Chemistry ,Copolymer ,Triethylamine ,Ethylene glycol - Abstract
Atom transfer radical polymerization was used to synthesize a well-defined poly(ethylene glycol)-b-poly(mercapto ethylacrylamide) (PEG-b-PMEAAm) diblock copolymer. Poly(ethylene glycol)-b-poly[N-(acryloxysuccinimide)](PEG-b-PNAS) was synthesized at 80 °C using methoxy-poly(ethylene glycol)-2-bromo propanoate (PEG-Br) and CuBr/2,2′-bipyridine as a macroinitiator and catalyst, respectively. The monomer conversion was determined by 1H nuclear magnetic resonance (NMR) spectroscopy. The resulting PEG-b-PNAS diblock copolymer was characterized by gel permeation chromatography, Fourier transform infrared (FT-IR), and 1H NMR spectroscopy. Disulfide groups were introduced by a simple reaction through the N-acryloxysuccinimide (NAS) moieties of the PEG-b-PNAS diblock copolymer with cystamine dihydrochloride in the presence of triethylamine. FT-IR spectroscopy was used to confirm the introduction of disulfide moieties into the polymer repeating units. Subsequently, a thiol-functionalized block copolymer was prepared using DL-dithiothreitol (DTT) as the reducing agent and the reduction step was monitored by 1H NMR spectroscopy. This thiol group was transformed easily to a disulfide bond using FeCl3 as an oxidizing agent. The transformation into disulfide could be visualized easily as insoluble polymeric particles formed from a clear solution of PEG-b-PMEAAm after oxidation.
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- 2011
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48. Stability-enhanced solid dispersion formulation of amorphous raloxifene hydrochloride
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Young Wook Choi, Ki Young Moon, Taek Hwan Shin, Duk Ki Kim, Chin Sung Cho, and Jong Lae Lim
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Materials science ,Chromatography ,Raloxifene Hydrochloride ,Impurity ,General Chemical Engineering ,General Chemistry ,Dispersion (chemistry) ,Dissolution ,Fluidized bed granulation ,Amorphous solid ,Drug content ,Nuclear chemistry - Abstract
To develop a stabilized formulation of amorphous raloxifene hydrochloride (RXF), solid dispersion granules (SDG) of amorphous RXF were prepared by fluidized bed granulation with non-pareil beads, compressed and filmcoated to produce solid dispersion tablets (SDT). Polymorphic changes in RXF were inhibited by SDG formulation. Drug content, impurity, and dissolution profile of SDT revealed that the SDT meets the acceptance criteria, and the content of RXF was maintained over 95% for 5 months at accelerated conditions of 40 °C and 75% R.H. In comparative dissolution study of reference tablet (Evista®) and SDT, the similarity factor (f2) provided evidence for similar dissolution profiles between two formulations. Therefore, we suggest the usefulness of SDT for the development of generic pharmaceuticals containing amorphous RXF.
- Published
- 2010
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49. Lubrication characteristics of dual piston ring in bent-axis type piston pumps
- Author
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Il-Hyun Beak, Jae-Youn Jung, Jae-Cheon Jo, Seok-Hyung Oh, Ju-Mi Park, and Ihn-Sung Cho
- Subjects
Engineering ,Piston pump ,Angle seat piston valve ,business.industry ,Mechanical Engineering ,Radial piston pump ,Axial piston pump ,Mechanical engineering ,Piston rod ,Mechanics of Materials ,Plunger pump ,Position-sensing hydraulic cylinder ,Piston ring ,business - Abstract
The bent-axis type of piston pump driven by the piston rod works by the piston rod driving the cylinder block; because of this the taper angle of the piston rod and the swivel angle between the cylinder block and the shaft are important design factors. If these factors cannot satisfy the conditions for optimum design, the friction loss between the cylinder bore and the piston increases, and the pump can fail to work under conditions of severe friction and wear. Since the piston reciprocates in the cylinder bore with high velocity, at the same time rotating on its own axis and revolving on the center of the cylinder block, a decrease of the volume efficiency is generated because of the leakage between the cylinder bore and the piston. Therefore, to prevent this, the piston ring is designed to be at the end of the piston, and the friction characteristics between the piston ring and the cylinder bore require further research due to their great influence on the performance of the piston pump. Thus, in this paper, the elastohydrodynamic lubrication (EHL) analysis of the film thickness, the pressure distribution, and the friction force, have been studied between the piston ring and the cylinder bore in the bent-axis type of piston pump. The analyzed results show that the friction force is influenced by the rotating speed and the discharge pressure.
- Published
- 2010
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50. Lubrication characteristics of a rotary compressor used for refrigeration and air-conditioning systems (the influence of alternative refrigerants)
- Author
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Jae-Youn Jung and Ihn-Sung Cho
- Subjects
Diaphragm compressor ,Engineering ,Reciprocating compressor ,business.industry ,Mechanical Engineering ,Mechanical engineering ,Refrigeration ,Tribology ,Refrigerant ,Mechanics of Materials ,Air conditioning ,Lubrication ,business ,Gas compressor - Abstract
The rolling piston type rotary compressor has been widely used for refrigeration and air-conditioning systems due to its compactness and high-speed characteristics. However, it is necessary to develop alternative refrigerants that can guarantee environmental protection. In addition, advanced refrigerant compressors must be further developed to overcome the compatibility problems inherent in refrigeration and air-conditioning systems. The refrigerant compressor is the most important mechanical component, which determines the performances of refrigeration and air-conditioning systems. Therefore, we theoretically investigated the lubrication characteristics of the rotary compressor currently used in both refrigeration and air-conditioning systems with an alternative refrigerant. In the theoretical investigation, the Runge-Kutta method is used to analyze the behavior of a rolling piston in the rotary compressor. Subsequently, the Newton-Raphson method is used, which provided good performance in the analysis of the elastohydrodynamic lubrication of the line contacts between a rolling piston and a vane in the rotary compressor. The results demonstrate that the alternative refrigerants influence the friction force and the energy loss between the vane and the rolling piston.
- Published
- 2010
- Full Text
- View/download PDF
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