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[Retracted]Gambigyeongsinhwan(4) Reduces Body Weight and Hepatic Lipid Accumulation in High Fat Diet-Fed Obese Male C57BL/6N Mice ([논문철회]고지방식이 마우스 비만모델에서 감비경신환(4)에 의한 체중감량과 간 지방축적의 변화)

  • Lee, Hye Rim;Ahn, Ye Ji;Lee, Hee Young;Lee, Hyung Hee;Kim, Dong Yeo;Yoon, Mi Chung;Lee, Yong Tae;Shin, Soon Shik
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.27 no.1
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    • pp.99-106
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    • 2013
  • We investigated the effects of gambigyeongsinhwan(GGH)(4) on body weight and non-alcoholic fatty liver disease(NAFLD) examined whether blood total cholesterol, LDL-cholesterol, free fatty acid and triglyceride levels and hepatic lipid accumulation are inhibited by it in high fat diet-fed obese male mice. 8 weeks old, high fat diet-fed obese male mice were divided into 5 groups: C57BL/6N normal, control, GGH(4)-1, GGH(4)-2 and GGH(4)-3. After mice were treated with GGH(4) for 8 weeks, we measured body weight gain, food intake, feeding efficiency ratio, fat weight, plasma ALT, leptin and lipid levels. We also did histological analysis for liver and fat on the mice. Compared with controls, GGH(4)-treated mice had lower body weight gain and adipose tissue weight, the magnitudes of which were prominent in GGH(4)-2. Compared with controls, GGH(4)-treated mice had lower feeding efficiency ratio and blood leptin level, the magnitudes of which was prominent in GGH(4)-2. Compared with controls, GGH(4)-treated mice had lower blood plasma total cholesterol, LDL-cholesterol, free fatty acid and triglyceride levels. Compared with controls, GGH(4)-2 treated mice had lower blood plasma ALT concentration. Consistent with their effects on body weight gain, the size of adipocytes were significantly decreased by GGH(4), whereas the adipocyte number per unit area was significantly increased, suggesting that GGH(4) decreased the number of large adipocytes. Hepatic lipid accumulation was decreased by GGH(4). In conclusion, these results suggest that GGH(4) exhibits anti-obesity effects through the modulation of feeding efficiency ratio and plasma obesity parameters. Moreover, it seems that GGH(4) also contributes to improve NAFLD through the regulation of plasma ALT and hepatic triglyceride accumulation.

Electrical response of tungsten diselenide to the adsorption of trinitrotoluene molecules (폭발물 감지 시스템 개발을 위한 TNT 분자 흡착에 대한 WSe2 소자의 전기적 반응 특성 평가)

  • Chan Hwi Kim;Suyeon Cho;Hyeongtae Kim;Won Joo Lee;Jun Hong Park
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.33 no.6
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    • pp.255-260
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    • 2023
  • As demanding the detection of explosive molecules, it is required to develop rapidly and precisely responsive sensors with ultra-high sensitivity. Since two-dimensional semiconductors have an atomically thin body nature where mobile carriers accumulate, the abrupt modulation carrier in the thin body channel can be expected. To investigate the effectiveness of WSe2 semiconductor materials as a detection material for TNT (Trinitrotoluene) explosives, WSe2 was synthesized using thermal chemical vapor deposition, and afterward, WSe2 FETs (Field Effect Transistors) were fabricated using standard photo-lithograph processes. Raman Spectrum and FT-IR (Fourier-transform infrared) spectroscopy reveal that the adsorption of TNT molecules induces the structural transition of WSe2 crystalline. The electrical properties before and after adsorption of TNT molecules on the WSe2 surface were compared; as -50 V was applied as the back gate bias, 0.02 μA was recorded in the bare state, and the drain current increased to 0.41 μA with a dropping 0.6% (w/v) TNT while maintaining the p-type behavior. Afterward, the electrical characteristics were additionally evaluated by comparing the carrier mobility, hysteresis, and on/off ratio. Consequently, the present report provides the milestone for developing ultra-sensitive sensors with rapid response and high precision.

Reliability of Skeletal Muscle Area Measurement on CT with Different Parameters: A Phantom Study

  • Dong Wook Kim;Jiyeon Ha;Yousun Ko;Kyung Won Kim;Taeyong Park;Jeongjin Lee;Myung-Won You;Kwon-Ha Yoon;Ji Yong Park;Young Jin Kee;Hong-Kyu Kim
    • Korean Journal of Radiology
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    • v.22 no.4
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    • pp.624-633
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    • 2021
  • Objective: To evaluate the reliability of CT measurements of muscle quantity and quality using variable CT parameters. Materials and Methods: A phantom, simulating the L2-4 vertebral levels, was used for this study. CT images were repeatedly acquired with modulation of tube voltage, tube current, slice thickness, and the image reconstruction algorithm. Reference standard muscle compartments were obtained from the reference maps of the phantom. Cross-sectional area based on the Hounsfield unit (HU) thresholds of muscle and its components, and the mean density of the reference standard muscle compartment, were used to measure the muscle quantity and quality using different CT protocols. Signal-to-noise ratios (SNRs) were calculated in the images acquired with different settings. Results: The skeletal muscle area (threshold, -29 to 150 HU) was constant, regardless of the protocol, occupying at least 91.7% of the reference standard muscle compartment. Conversely, normal attenuation muscle area (30-150 HU) was not constant in the different protocols, varying between 59.7% and 81.7% of the reference standard muscle compartment. The mean density was lower than the target density stated by the manufacturer (45 HU) in all cases (range, 39.0-44.9 HU). The SNR decreased with low tube voltage, low tube current, and in sections with thin slices, whereas it increased when the iterative reconstruction algorithm was used. Conclusion: Measurement of muscle quantity using HU threshold was reliable, regardless of the CT protocol used. Conversely, the measurement of muscle quality using the mean density and narrow HU thresholds were inconsistent and inaccurate across different CT protocols. Therefore, further studies are warranted in future to determine the optimal CT protocols for reliable measurements of muscle quality.

Proof-of-principle Experimental Study of the CMA-ES Phase-control Algorithm Implemented in a Multichannel Coherent-beam-combining System (다채널 결맞음 빔결합 시스템에서 CMA-ES 위상 제어 알고리즘 구현에 관한 원리증명 실험적 연구)

  • Minsu Yeo;Hansol Kim;Yoonchan Jeong
    • Korean Journal of Optics and Photonics
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    • v.35 no.3
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    • pp.107-114
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    • 2024
  • In this study, the feasibility of using the covariance-matrix-adaptation-evolution-strategy (CMA-ES) algorithm in a multichannel coherent-beam-combining (CBC) system was experimentally verified. We constructed a multichannel CBC system utilizing a spatial light modulator (SLM) as a multichannel phase-modulator array, along with a coherent light source at 635 nm, implemented the stochastic-parallel-gradient-descent (SPGD) and CMA-ES algorithms on it, and compared their performances. In particular, we evaluated the characteristics of the CMA-ES and SPGD algorithms in the CBC system in both 16-channel rectangular and 19-channel honeycomb formats. The results of the evaluation showed that the performances of the two algorithms were similar on average, under the given conditions; However, it was verified that under the given conditions the CMA-ES algorithm was able to operate with more stable performance than the SPGD algorithm, as the former had less operational variation with the initial phase setting than the latter. It is emphasized that this study is the first proof-of-principle demonstration of the CMA-ES phase-control algorithm in a multichannel CBC system, to the best of our knowledge, and is expected to be useful for future experimental studies of the effects of additional channel-number increments, or external-phase-noise effects, in multichannel CBC systems based on the CMA-ES phase-control algorithm.

Anti-oxidative Activity of Lycopene Via the Induction of HO-1 Expression by MAPK/Nrf2 Signaling Pathway in RAW 264.7 Cells (RAW 264.7 세포에서 Lycopene의 MAPK/Nrf2/HO-1 신호 전달 체계를 통한 항산화 효과)

  • Chung-Mu Park;Hyun An;Hyun-Seo Yoon
    • Journal of The Korean Society of Integrative Medicine
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    • v.12 no.1
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    • pp.1-10
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    • 2024
  • Purpose: Lycopene is abundantly contained in Tomatoes and is known for diverse biological activities such as antioxidant, anti-inflammatory, and anticancer effects. In this study, the antioxidative potential of lycopene was investigated through the induction of hemeoxygenase (HO)-1 by nuclear factor-erythroid 2 p45-related factor2 (Nrf2) and upstream signaling molecules, mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)/Aktin RAW 264.7 cells. Methods: The antioxidative potential of lycopene against oxidative stress and its molecular mechanisms were determined by the cell viability assay, intracellular reactive oxygen species (ROS) formation assay, and Western blot analysis in RAW 264.7 cells. Results: Lycopene treatment significantly attenuated tert-butyl hydroperoxide (t-BHP) induced intracellular ROS formation in a dose-dependent manner without any cytotoxicity. In addition, 50 µM of lycopene for 6 h treatment induced potent HO-1 expression and its transcription factor, Nrf2. MAPK and PI3K/Aktwere also analyzed due to their critical roles in the regulation of cellular redox homeostasis against oxidative damage. As a result, phosphorylation of extracellular regulated kinase (ERK) was significantly induced by lycopene treatment while the activated status of c-Jun NH2-terminal kinase (JNK), p38, and Akt, were not given any effect. To confirm the antioxidative mechanism of HO-1 mediated by ERK activation, each selective inhibitor was employed in a protection assay, in which oxidative damage occurred by t-BHP. Lycopene, SnPP, and CoPP treatments reflected accelerated HO-1 expression could be a protective role against oxidative damage-initiated cell death. A selective inhibitor for ERK significantly inhibited the lycopene-induced cytoprotective effect but selective inhibitors for other signaling molecules did not attenuate the rate of t-BHP-induced cell death. Conclusion: In conclusion, lycopene potently scavenged intracellular ROS formation and enhanced the HO-1 mediated antioxidative potential through the modulation of Nrf2, MAPK signaling pathway in RAW 264.7 cells.

Anti-obesity effects of Glycyrrhiza uralensis ethanol extract on the inhibition of 3T3-L1 adipocyte differentiation in high-fat diet-induced C57BL/6J mice (감초 주정추출물의 3T3-L1 지방세포 분화 억제 및 고지방 식이로 유도된 C57BL/6J 마우스에 대한 항비만 효과)

  • Seon Kyeong Park;Jangho Lee;Soo Hyun Park;Yu Geon Lee
    • Food Science and Preservation
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    • v.30 no.4
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    • pp.716-728
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    • 2023
  • The anti-adipogenic activity of Glycyrrhiza uralensis was investigated by examining the effects of its ethanol extract (GUE) on a mouse model with a high-fat diet (HFD) and 3T3-L1 preadipocytes during adipocyte differentiation. GUE administration for eight weeks significantly reduced weight gain in mice fed an HFD. GUE effectively inhibited 3T3-L1 preadipocyte differentiation and lipid droplet accumulation. This inhibitory effect is associated with the downregulation of key adipogenic regulators, including PPARγ and C/EBPα, and the modulation of adipose metabolism regulators, such as Fasn and Fabp4. LC-Q-TOF-MS analysis identified twelve phenolic and flavonoid compounds, including liquiritigenin and licorice saponin, in the GUE. These findings demonstrate that the anti-obesity effect of the GUE is attributed to the biological activity of its phenolic and flavonoid compounds. Therefore, the GUE has potential anti-obesity activity. Moreover, further studies on the isolation of bioactive components from the GUE and the investigation of the underlying molecular mechanisms of the GUE are required to establish its efficacy in metabolic disorders, including obesity.

Impact of Photon-Counting Detector Computed Tomography on Image Quality and Radiation Dose in Patients With Multiple Myeloma

  • Alexander Rau;Jakob Neubauer;Laetitia Taleb;Thomas Stein;Till Schuermann;Stephan Rau;Sebastian Faby;Sina Wenger;Monika Engelhardt;Fabian Bamberg;Jakob Weiss
    • Korean Journal of Radiology
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    • v.24 no.10
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    • pp.1006-1016
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    • 2023
  • Objective: Computed tomography (CT) is an established method for the diagnosis, staging, and treatment of multiple myeloma. Here, we investigated the potential of photon-counting detector computed tomography (PCD-CT) in terms of image quality, diagnostic confidence, and radiation dose compared with energy-integrating detector CT (EID-CT). Materials and Methods: In this prospective study, patients with known multiple myeloma underwent clinically indicated whole-body PCD-CT. The image quality of PCD-CT was assessed qualitatively by three independent radiologists for overall image quality, edge sharpness, image noise, lesion conspicuity, and diagnostic confidence using a 5-point Likert scale (5 = excellent), and quantitatively for signal homogeneity using the coefficient of variation (CV) of Hounsfield Units (HU) values and modulation transfer function (MTF) via the full width at half maximum (FWHM) in the frequency space. The results were compared with those of the current clinical standard EID-CT protocols as controls. Additionally, the radiation dose (CTDIvol) was determined. Results: We enrolled 35 patients with multiple myeloma (mean age 69.8 ± 9.1 years; 18 [51%] males). Qualitative image analysis revealed superior scores (median [interquartile range]) for PCD-CT regarding overall image quality (4.0 [4.0-5.0] vs. 4.0 [3.0-4.0]), edge sharpness (4.0 [4.0-5.0] vs. 4.0 [3.0-4.0]), image noise (4.0 [4.0-4.0] vs. 3.0 [3.0-4.0]), lesion conspicuity (4.0 [4.0-5.0] vs. 4.0 [3.0-4.0]), and diagnostic confidence (4.0 [4.0-5.0] vs. 4.0 [3.0-4.0]) compared with EID-CT (P ≤ 0.004). In quantitative image analyses, PCD-CT compared with EID-CT revealed a substantially lower FWHM (2.89 vs. 25.68 cy/pixel) and a significantly more homogeneous signal (mean CV ± standard deviation [SD], 0.99 ± 0.65 vs. 1.66 ± 0.5; P < 0.001) at a significantly lower radiation dose (mean CTDIvol ± SD, 3.33 ± 0.82 vs. 7.19 ± 3.57 mGy; P < 0.001). Conclusion: Whole-body PCD-CT provides significantly higher subjective and objective image quality at significantly reduced radiation doses than the current clinical standard EID-CT protocols, along with readily available multi-spectral data, facilitating the potential for further advanced post-processing.

A simple approach to simulate the size distribution of suspended sediment (부유사 입경분포 모의를 위한 간편법)

  • Kwon, Minhyuck;Byun, Jisun;Son, Minwoo
    • Journal of Korea Water Resources Association
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    • v.57 no.5
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    • pp.347-357
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    • 2024
  • Numerous prior studies have delineated the size distribution of noncohesive sediment in suspension, focusing on mean size and standard deviation. However, suspensions comprise a heterogeneous mixture of sediment particles of varying sizes. The transport dynamics of suspended sediment in turbulent flow are intimately tied to settling velocities calculated based on size and density. Consequently, understanding the grain size distribution becomes paramount in comprehending sediment transport phenomena for noncohesive sediment. This study aims to introduce a straightforward modeling approach for simulating the grain size distribution of suspended sediment amidst turbulence. Leveraging insights into the contrast between cohesive and noncohesive sediment, we have meticulously revised a stochastic flocculation model originally designed for cohesive sediment to aptly simulate the grain size distribution of noncohesive sediment in suspension. The efficacy of our approach is corroborated through a meticulous comparison between experimental data and the grain size distribution simulated by our newly proposed model. Through numerical simulations, we unveil that the modulation of grain size distribution of suspended sediment is contingent upon the sediment transport capacity of the carrier fluid. Hence, we deduce that our simplified approach to simulating the grain size distribution of suspended sediment, integrated with a sediment transport model, serves as a robust framework for elucidating the pivotal bulk properties of sediment transport.

Amelioration of colitis progression by ginseng-derived exosome-like nanoparticles through suppression of inflammatory cytokines

  • Jisu Kim;Shuya Zhang ;Ying Zhu;Ruirui Wang;Jianxin Wang
    • Journal of Ginseng Research
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    • v.47 no.5
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    • pp.627-637
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    • 2023
  • Background: Damage to the healthy intestinal epithelial layer and regulation of the intestinal immune system, closely interrelated, are considered pivotal parts of the curative treatment for inflammatory bowel disease (IBD). Plant-based diets and phytochemicals can support the immune microenvironment in the intestinal epithelial barrier for a balanced immune system by improving the intestinal microecological balance and may have therapeutic potential in colitis. However, there have been only a few reports on the therapeutic potential of plant-derived exosome-like nanoparticles (PENs) and the underlying mechanism in colitis. This study aimed to assess the therapeutic effect of PENs from Panax ginseng, ginseng-derived exosome-like nanoparticles (GENs), in a mouse model of IBD, with a focus on the intestinal immune microenvironment. Method: To evaluate the anti-inflammatory effect of GENs on acute colitis, we treated GENs in Caco2 and lipopolysaccharide (LPS) -induced RAW 264.7 macrophages and analyzed the gene expression of proinflammatory cytokines and anti-inflammatory cytokines such as TNF-α, IL-6, and IL-10 by real-time PCR (RT-PCR). Furthermore, we further examined bacterial DNA from feces and determined the alteration of gut microbiota composition in DSS-induced colitis mice after administration of GENs through 16S rRNA gene sequencing analysis. Result: GENs with low toxicity showed a long-lasting intestinal retention effect for 48 h, which could lead to effective suppression of pro-inflammatory cytokines such as TNF-α and IL-6 production through inhibition of NF-κB in DSS-induced colitis. As a result, it showed longer colon length and suppressed thickening of the colon wall in the mice treated with GENs. Due to the amelioration of the progression of DSS-induced colitis with GENs treatment, the prolonged survival rate was observed for 17 days compared to 9 days in the PBS-treated group. In the gut microbiota analysis, the ratio of Firmicutes/Bacteroidota was decreased, which means GENs have therapeutic effectiveness against IBD. Ingesting GENs would be expected to slow colitis progression, strengthen the gut microbiota, and maintain gut homeostasis by preventing bacterial dysbiosis. Conclusion: GENs have a therapeutic effect on colitis through modulation of the intestinal microbiota and immune microenvironment. GENs not only ameliorate the inflammation in the damaged intestine by downregulating pro-inflammatory cytokines but also help balance the microbiota on the intestinal barrier and thereby improve the digestive system.

Combined toxic effects of water temperature and polystyrene beads in the brackish water flea (기수산 물벼룩에서 수온과 polystyrene beads의 복합 독성)

  • Youn-Ha Lee;Jong-Seok Park;Chaerin Park;Sang-Hyun Cho;Je-Won Yoo;Young-Mi Lee
    • Korean Journal of Environmental Biology
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    • v.41 no.4
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    • pp.386-399
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    • 2023
  • Microplastics and nanoplastics (NMPs) are considered one of hazardous contaminants in marine ecosystems due to their toxic effects, such as reproduction disorder and oxidative stress, on marine organisms. Although water temperature is rising due to global climate change, little information on the toxicological interaction between NMPs and temperature is available. Therefore, in this study, we confirmed the toxicity of NMPs (polystyrene [PS] beads; 0.05- and 6-㎛) on brackish water fleas (Diaphanosoma celebensis) depending on increased temperature (30℃ and 35℃) at individual and molecular levels. In the chronic toxicity test, the group exposed to high temperatures showed an earlier first reproduction time compared to the normal temperatures group, but it was delayed by co-exposure to NMPs at 35℃. Notably, the total reproduction decreased significantly only after 0.05-㎛ PS beads exposure at 30℃. Interaction analysis showed that first reproduction time, modulation of the antioxidant-related gene (GSTS1), heat shock gene (Hsp70), and ecdysteroid pathway-related genes (EcR_A, EcR_B, and CYP314A1) were closely related to temperature and PS beads size. These results indicate that microplastics have size-dependent toxicity, and their toxicity can be enhanced at high temperatures. In addition, higher temperatures and PS beads exposure may have negative effects on reproduction. This study suggests that various factors such as water temperature should be considered when evaluating the toxicity of microplastics in marine ecosystems, and provides an understanding of the complex toxic interaction between water temperature and microplastics for marine zooplankton.