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31. Zingone (Thoracosphaerales, Dinophyceae) from Korean Coastal Waters

Author

Kim, Hyun Jung, Li, Zhun, Kang, Nam Seon, Gu, Haifeng, Kim, Daekyung, Seo, Min Ho, Lee, Sang Deuk, Yun, Suk Min, Oh, Seok-Jin, and Shin, Hyeon Ho

Subjects
intercalary plate, Scrippsiella, resting cyst, ribotype, precingular plate
Abstract

The dinoflagellate genus Scrippsiella is a common member of phytoplankton and their cysts are also frequently reported in coastal sediments worldwide. However, the diversity of Scrippsiella in Korean waters has not been fully investigated. Here, several isolates of Scrippsiella precaria collected from Korean waters and germinated from resting cysts were examined using light and scanning electron microscopy. The resting cysts were characterized by pointed calcareous spines and one or two red accumulation bodies, and the archeopyle was mesoepicystal, representing the loss of 2–4′ and 1–3a paraplates. Rounded resting cysts were found in culture, and an increase in spine length was observed until 8 days of development. Korean isolates of S. precaria had the plate formula of Po, X, 4′, 3a, 7″, 6C, 4S, 5‴, 2⁗. There were differences in the cell size and location of the red body between Korean isolates and previously described cells of S. precaria. In addition, the Korean isolates of S. precaria had two types of the 5″ plate that either contacted the 2a plate or not. Molecular phylogeny based on internal transcribed spacer (ITS) and large subunit (LSU) rDNA sequences revealed that the Korean isolates were nested within the subclade of PRE (S. precaria and related species) in the clade of Scrippsiella sensu lato, and that the PRE subclade had two ribotypes: ribotype 1 consisting of the isolates from Korea, China, and Australia, and ribotype 2 consisting of the isolates from Italy and Greece. Lineages between isolates of ribotype 1 were likely to be related to the dispersal by ocean currents and ballast waters from international shipping, and the two types of spine shapes and locations of the 5″ plates may be a distinct feature for ribotype 1.

Published
2021
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35. Mask Branch Network: Weakly Supervised Branch Network with a Template Mask for Classifying Masses in 3D Automated Breast Ultrasound.

Author

Kim, Daekyung, Park, Haesol, Jang, Mijung, and Lee, Kyong-Joon

Subjects
BREAST, BREAST ultrasound, MEDICAL masks, NETWORK performance, DIAGNOSTIC imaging, CANCER diagnosis, IMAGE segmentation
Abstract

Automated breast ultrasound (ABUS) is being rapidly utilized for screening and diagnosing breast cancer. Breast masses, including cancers shown in ABUS scans, often appear as irregular hypoechoic areas that are hard to distinguish from background shadings. We propose a novel branch network architecture incorporating segmentation information of masses in the training process. The branch network is integrated into neural network, providing the spatial attention effect. The branch network boosts the performance of existing classifiers, helping to learn meaningful features around the target breast mass. For the segmentation information, we leverage the existing radiology reports without additional labeling efforts. The reports, which is generated in medical image reading process, should include the characteristics of breast masses, such as shape and orientation, and a template mask can be created in a rule-based manner. Experimental results show that the proposed branch network with a template mask significantly improves the performance of existing classifiers. We also provide qualitative interpretation of the proposed method by visualizing the attention effect on target objects. [ABSTRACT FROM AUTHOR]

Published
2022
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36. Microalgae as an Effective Recovery Agent for Vanadium in Aquatic Environment.

Author

Kim, Hee Su, Kim, Minsik, Park, Won-Kun, Yang, Won-Geun, Nayak, Manoranjan, Shin, Hyeon Ho, Cho, Kichul, Kim, Daekyung, and Oda, Tatsuya

Subjects
INDUCTIVELY coupled plasma mass spectrometry, VANADIUM
Abstract

Given that vanadium is a valuable material, the implementation of vanadium recycling processes is thus necessary to enhance the element's value chain as well as minimize its undesirable environmental consequences. Among various remediation methods available, a biological method based on microalgal adsorption is known to be eco-friendly and calls for further investigations. Herein, we evaluated V2O5 adsorption efficiencies of four different microalgal strains: Nannochloropsis oculata, Heterocapsa circularisquama, Chattonella marina, and Chattonella antiqua. Inductively coupled plasma mass spectrometry (ICP-MS) data indicated that vanadium concentration in the culture medium of Nannochloropsis oculata was reduced from 4.61 ± 0.11 mg L−1 to 1.85 ± 0.21 mg L−1 after being exposed to V2O5 solution for 24 h, whereas the supernatants of the other three strains displayed no change in vanadium ion concentration. Therefore, our results indicated a strong potential of Nannochloropsis oculata for recycling vanadium with approximately 59.9% of vanadium ion removal efficiency. Furthermore, morphological observation of Nannochloropsis oculata using scanning electron microscopy (SEM) indicated that the cells were able to maintain their intact morphology even under the presence of high concentrations of heavy metals. Due to the high adsorption efficiency and robustness of Nannochloropsis oculata, the results collectively support it as a potential strain for V2O5 recovery. [ABSTRACT FROM AUTHOR]

Published
2022
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37. Fake news on you, Not me: The Third-Person Effects of Fake News in South Korea.

Author

Yoo, Joseph, Kim, Daekyung, and Kim, Wi-Geun

Subjects
FAKE news, PRESIDENTIAL elections, INTERNET surveys, FRENCH presidential elections
Abstract

This study explored the perceptual components of the third-person effects of fake news during the 2017 presidential election in South Korea. Specifically, we examined self-other disparities in perceptions of the effects of fake news using data from an online panel survey. The results indicated that the participants considered the influence of fake news to be greater on others than on themselves. We also found political interest and fact-checking to be significant predictors of the self-other disparities associated with perceptions of fake news. The findings of this study offer fresh insights into third-person effects in the age of post-truth politics. [ABSTRACT FROM AUTHOR]

Published
2022
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46. Anti-inflammatory activity of hydrosols from Tetragonia tetragonoides in LPS-induced RAW 264.7 cells

Author

Ko, Eun-Yi, Cho, Su-Hyeon, Kang, Kyungpil, Kim, Gibeom, Lee, Ji-Hyeok, Jeon, You-Jin, Kim, Daekyung, Ahn, Ginnae, and Kim, Kil-Nam

Subjects
0301 basic medicine, 01 natural sciences, NF-κB, 0104 chemical sciences, 010404 medicinal & biomolecular chemistry, 03 medical and health sciences, 030104 developmental biology, hydrosols, MAPKs, Original Article, NF-kappaB, lipids (amino acids, peptides, and proteins), Tetragonia tetragonoides, NF- κB, anti-inflammatory
Abstract

The present study was performed to investigate the anti-inflammatory activity of Tetragonia tetragonoides hydro- sols (TTH) and its underlying mechanism in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Gas chromatog- raphy (GC) coupled with mass spectrometry and retention index calculations showed that TTH were mainly com- posed of tetratetracontane (29.5 %), nonacosane (27.6 %), and oleamide (17.1 %). TTH significantly decreased the production of nitric oxide (NO), prostaglandin E2 (PGE2), interleukin (IL)-6, and IL-1β in LPS-stimulated RAW 264.7 cells. Consistent with these observations, TTH treatment decreased the protein expression levels of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2). The molecular mechanism of its anti-inflamma- tory activity was found to be associated with inhibition of nuclear factor-kappa B (NF-κB) phosphorylation and nuclear translocation of NF-κB 65. Furthermore, TTH markedly suppressed the LPS-induced phosphorylation of mitogen-activated protein kinases (MAPKs). Taken together, these data indicate that TTH exerts an anti-inflam- matory activity by inhibiting the NF-κB and MAPK signaling pathways in LPS-stimulated RAW 264.7 cells., EXCLI Journal;Vol. 16 2017

Published
2017

47. 6-7-Dimethoxy-4-methylcoumarin suppresses pro-inflammatory mediator expression through inactivation of the NF-κB and MAPK pathways in LPS-induced RAW 264.7 cells

Author

Kim, Kil-Nam, Yang, Hye-Won, Ko, Seok-Chun, Ko, Yeong-Jong, Kim, Eun-A, Roh, Seong Woon, Ko, Eun-Yi, Ahn, Ginnae, Heo, Soo-Jin, Jeon, You-Jin, Yoon, Weon-Jong, Hyun, Chang-Gu, and Kim, Daekyung

Subjects
MAPKs, RAW 264.7 cells, lipids (amino acids, peptides, and proteins), Original Article, NF-kappaB, 6,7-Dimethoxy-4-methylcoumarin (DMC), anti-inflammatory
Abstract

In this study, we investigated the ability of 6,7-dimethoxy-4-methylcoumarin (DMC) to inhibit lipopolysaccharide (LPS)-induced expression of pro-inflammatory mediators in mouse macrophage (RAW 264.7) cells, and the molecular mechanism through which this inhibition occurred. Our results indicated that DMC downregulated LPS-induced nitric oxide (NO) synthase (iNOS) and cyclooxygenase-2 (COX-2) expression, thereby reducing the production of NO and prostaglandin E2 (PGE2) in LPS-activated RAW 264.7 cells. Furthermore, DMC suppressed LPS-induced production of pro-inflammatory cytokines such as interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α. To elucidate the mechanism underlying the anti-inflammatory activity of DMC, we assessed its effects on the mitogen-activated protein kinase (MAPK) pathway and the activity and expression of nuclear transcription factor kappa-B (NF-κB). The experiments demonstrated that DMC inhibited LPS-induced phosphorylation of extracellular signal-regulated kinases (ERKs), c-Jun N-terminal kinase (JNK), and p38. In addition, it attenuated LPS-induced NF-κB activation via the inhibition of IκB-α phosphorylation. Taken together, these data suggest that DMC exerts its anti-inflammatory effects in RAW 264.7 cells through the inhibition of LPS-stimulated NF-κB and MAPK signaling, thereby downregulating the expression of pro-inflammatory mediators.

Published
2014

49. Anti-inflammatory effect of supercritical extract and its constituents from Ishige okamurae

Author

Ko, Eun-Yi, Yoon, Weon-Jong, Lee, Hae-Won, Heo, Soo-Jin, Ko, Young-Hwan, Fernando, I.P. Shanura, Cho, Kichul, Lee, Chi-Heon, Hur, Sung-Pyo, Cho, Su-Hyeon, Ahn, Ginnae, Kim, Daekyung, and Kim, Kil-Nam

Subjects
0301 basic medicine, linoleic acid, NF-κB, 03 medical and health sciences, 030104 developmental biology, Ishige okamurae, Original Article, NF-kappaB, lipids (amino acids, peptides, and proteins), supercritical fluid extraction, NF- κB, anti-inflammatory
Abstract

The anti-inflammatory properties of the supercritical fluid extract of Ishige okamurae (SFEIO) on lipopolysaccharide (LPS)-stimulated murine RAW 264.7 macrophages. The lipid profile of the SFEIO, reviled the presence of palmitic acid (220.2 mg/g), linoleic acid (168.0 mg/g), and oleic acid (123.0 mg/g). SFEIO was found to exert it’s anti-inflammatory effects through inhibiting nitric oxide (NO), prostaglandin E2 (PGE2), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 production in LPS-stimulated RAW 264.7 cells, without inducing cytotoxicity. SFEIO did not effect on the LPS-induced p38 kinase phosphorylation, whereas it attenuated the extracellular-related signaling kinase (ERK) and c-Jun N-terminal kinase (JNK) phosphorylation. Furthermore, SFEIO inhibited the LPS-induced IκB-α degradation and p50 NF-κB activation. These results suggest that SFEIO exerts its anti-inflammatory effects in LPS-activated RAW 264.7 cells by down-regulating the activation of ERK, JNK, and NF-κB., EXCLI Journal;Vol. 15, 2016

Published
2016

50. Picturing the Iraq War: constructing the image of war in the British and US press

Author

Fahmy, Shahira and Kim, Daekyung

Subjects
The New York Times (Newspaper) -- Comparative analysis, The Guardian (London, United Kingdom) (Newspaper) -- Comparative analysis, British newspapers -- Comparative analysis, War -- Media coverage, War -- Comparative analysis, Business, Literature/writing, Mass communications
Published
2008

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