• Title/Summary/Keyword: Chang-rae Lee

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Rheumatic Arthritis-induced Alteration of Morphology and Function in Muscles

  • Hong, Yun-Kyung;Kim, Joo-Heon;Javaregowda, Palaksha Kanive;Lee, Sang-Kil;Lee, Sang-Rae;Chang, Kyu-Tae;Hong, Yong-Geun
    • Reproductive and Developmental Biology
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    • v.35 no.2
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    • pp.151-157
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    • 2011
  • Clinical arthritis is typically divided into rheumatoid arthritis (RA) and osteoarthritis (OA). Arthritis-induced muscle weakness is a major problem in aged people, leading to a disturbance of balance during the gait cycle and frequent falls. The purposes of the present study were to confirm fiber type-dependent expression of muscle atrophy markers induced by arthritis and to identify the relationship between clinical signs and expression of muscle atrophy markers. Mice were divided into four experimental groups as follows: (1) negative control (normal), (2) positive control (CFA+acetic acid), (3) RA group (CFA+acetic acid+type II collagen), and (4) aging-induced OA group. DBQA/1J mice (8 weeks of age) were injected with collagen (50 ${\mu}g/kg$), and physiological (body weight) and pathological (arthritis score and paw thickness) parameters were measured once per week. The gastrocnemius muscle from animals in each group was removed, and the expression of muscle atrophy markers (MAFbx and MuRF1) and myosin heavy chain isoforms were analyzed by reverse transcription-polymerase chain reaction. No significant change in body weight occurred between control groups and collagen-induced RA mice at week 10. However, bovine type II collagen induced a dramatic increase in clinical score or paw thickness at week 10 (p<0.01). Concomitantly, the expression of the muscle atrophy marker MAFbx was upregulated in the RA and OA groups (p<0.01). A dramatic reduction in myosin heavy chain (MHC)-$I{\beta}$ was seen in the gastrocnemius muscles from RA and OA mice, while only a slight decrease in MHC-IIb was seen. These results suggest that muscle atrophy gene expression occurred in a fiber type-specific manner in both RA- and OA-induced mice. The present study suggests evidence regarding why different therapeutic interventions are required between RA and OA.

Development of MRI Scanning Technique that is Comfortable for Patients with Anxiety Disorder

  • Cho, Moo-Seong;Cho, Jae-Hwan;Chang, Yong-Min;Cho, Yong-Ho;Zeon, Seok-Kil;Dong, Kyung-Rae;Chung, Woon-Kwan;Lee, Hae-Kag;Kim, Hyun-Ju;Bae, Jae-Young;Ahn, Jae-Ouk;Lee, Sang-Jeong
    • Journal of Magnetics
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    • v.16 no.4
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    • pp.350-362
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    • 2011
  • The principal objective of this study was to develop a scanning technique that helps patients reduce their anxiety and relax their physical tension in the MRI system. The study targeted 10 healthy persons with no medical history of anxiety disorder in the past and with no current clinically diagnosed anxiety disorder, as well as 10 patients who were currently experiencing an anxiety disorder during the MRI scanning. The focusing board assembly was self-manufactured to conduct a clinical experiment via MRI scans. As a method to confirm the efficacy of the experiment, the bio meter was used to measure brainwaves from the study targets that were divided into the normal person group (A), who felt no anxiety in the MRI system and the experimental group, (B) who did experience anxiety in the MRI system. The two groups were compared between the cases in which the focusing board assembly was used and not used after measurements were conducted using the model MRI system and the bio meter. According to the comparison and analysis results, low measurements of the ${\alpha}$ wave indicate highly effective relaxation of tension. In the normal person group, the ${\alpha}$ wave measurement showed almost no difference between cases in which the focusing board assembly was used and cases in which it was not used. In the experimental group, the $\acute{a}$ wave measurements were lower in cases in which the focusing board assembly was used than in cases in which the focusing board assembly was not used; this was indicative of a profound relaxation effect.

Gain of a New Exon by a Lineage-Specific Alu Element-Integration Event in the BCS1L Gene during Primate Evolution

  • Park, Sang-Je;Kim, Young-Hyun;Lee, Sang-Rae;Choe, Se-Hee;Kim, Myung-Jin;Kim, Sun-Uk;Kim, Ji-Su;Sim, Bo-Woong;Song, Bong-Seok;Jeong, Kang-Jin;Jin, Yeung-Bae;Lee, Youngjeon;Park, Young-Ho;Park, Young Il;Huh, Jae-Won;Chang, Kyu-Tae
    • Molecules and Cells
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    • v.38 no.11
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    • pp.950-958
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    • 2015
  • BCS1L gene encodes mitochondrial protein and is a member of conserved AAA protein family. This gene is involved in the incorporation of Rieske FeS and Qcr10p into complex III of respiratory chain. In our previous study, AluYRa2-derived alternative transcript in rhesus monkey genome was identified. However, this transcript has not been reported in human genome. In present study, we conducted evolutionary analysis of AluYRa2-exonized transcript with various primate genomic DNAs and cDNAs from humans, rhesus monkeys, and crabeating monkeys. Remarkably, our results show that AluYRa2 element has only been integrated into genomes of Macaca species. This Macaca lineage-specific integration of AluYRa2 element led to exonization event in the first intron region of BCS1L gene by producing a conserved 3' splice site. Intriguingly, in rhesus and crabeating monkeys, more diverse transcript variants by alternative splicing (AS) events, including exon skipping and different 5' splice sites from humans, were identified. Alignment of amino acid sequences revealed that AluYRa2-exonized transcript has short N-terminal peptides. Therefore, AS events play a major role in the generation of various transcripts and proteins during primate evolution. In particular, lineage-specific integration of Alu elements and species-specific Alu-derived exonization events could be important sources of gene diversification in primates.

Effects of Electro and Laser Acupuncture Treatment with $GB_{39}$ and $GB_{34}$ on Neuropathic Pain in Rats Induced by Tibial and Sural Nerve Ligation (현종(懸鍾)($GB_{39}$).양릉천(陽陵泉)($GB_{34}$)의 전침(電鍼) 및 레이저침이 백서(白鼠)의 신경병리성(神經病理性) 동통(疼痛)에 미치는 영향)

  • Kim, Yong Se;Lee, Ju Hee;Lee, Sang Hyun;Na, Chang Su;Cho, Myoung Rae
    • Journal of Acupuncture Research
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    • v.30 no.3
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    • pp.125-134
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    • 2013
  • Objectives : We studied the effects of electro and laser acupuncture treatment with $GB_{39}$ and $GB_{34}$ on neuropathic pain in rats induced by tibial and sural nerve ligation. Methods : To produce the model of neuropathic pain, the tibial and sural nerves of rats were ligated by a 6-0 silk thread. Three days after the neuropathic surgery, only electro acupuncture(EA), electro acupuncture and 830 nm laser acupuncture(EA-LA-1), and electro acupuncture and 904 nm laser acupuncture(EA-LA-2) were treated with $GB_{39}$ and $GB_{34}$ twice a week for 8 weeks. We observed the withdrawal response of neuropathic rats' legs by von Frey filament and acetone stimulation. We also observed c-fos and nocieptin on the central gray area in the midbrain of neuropathic rats. Results : As we observed the effect of mechanical allodynia, the EA and EA-LA-1 groups in 5 and 6 weeks and the EA-LA-2 group in 6 weeks increased significantly compared with the control group. As for the effect of c-fos activity in the central gray region, the EA, EA-LA-1, and EA-LA-2 groups decreased significantly compared with the control group. The EA-LA-2 group increased significantly compared with the control group as regards the effect of nociceptin activity in the central gray region. Conclusions : We noticed the synergic effect of electro and laser acupuncture treatment because the EA-LA-1 and EA-LA-2 groups had more controllable effect compared with the control group. This study can be used in clinical therapy for neuropathic pain.

Utilization of Chitosan Hydrolysate as a Natural Food Preservative for Fish Meat Paste Products (키토산 효소분해물을 이용한 어육연제품의 유통기간 연장)

  • Cho, Hak-Rae;Chang, Dong-Suck;Lee, Won-Dong;Jeong, Eun-Tak;Lee, Eun-Woo
    • Korean Journal of Food Science and Technology
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    • v.30 no.4
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    • pp.817-822
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    • 1998
  • The authors found out that Aspergillus oryzae ATCC 22787 has the activity to produce a pretty strong chitosanase. Therefore, the strain was used for preparing the chitosan hydrolysate with high antimicrobial activity. The antimicrobial activity of the chitosan hydrolysate was increased gradually with decreasing of viscosity of the solution. The chitosan hydrolysate showing viscosity $5{\sim}10{\;}cp{\;}(30^{\circ}C)$ of 2% solution was revealed the most strong antimicrobial activity. The growth of the Bacillus sp. isolated from the fish meat paste was inhibited with the concentration of 50 ppm. The astringent taste of chitosan solution was reduced with decreasing of viscosity of the solution. The fish meat paste products containing 0.3% chitosan hydrolysate was extended its shelf life by 6 days stored at $15^{\circ}C$, 4 days at $20^{\circ}C$ and 2 days at $30^{\circ}C$.

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Changes in the Prosthesis Types Used for Aortic Valve Replacement after the Introduction of Sutureless and Rapid Deployment Valves in Korea: A Nationwide Population-Based Cohort Study

  • Woo, Hyeok Sang;Hwang, Ho Young;Kim, Ho Jin;Kim, Joon Bum;Lee, Sak;Lim, Cheong;Chang, Byung-Cheul;Lee, Na Rae;Suh, Youshin;Choi, Jae Woong
    • Journal of Chest Surgery
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    • v.54 no.5
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    • pp.369-376
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    • 2021
  • Background: Sutureless and rapid deployment valves for aortic valve replacement (AVR) were introduced in Korea in December 2016. This study evaluated changing trends in the prosthetic valves used for AVR in Korea after the introduction of sutureless and rapid deployment valves. Methods: From December 2016 to December 2018, 4,899 patients underwent AVR in Korea. After applying the exclusion criteria, 4,872 patients were analyzed to determine changes in the type of prosthetic valve used for AVR. The study period was divided into 5 groups corresponding to 5-month intervals. Results: The total number of AVR cases was 194.88±28.78 per month during the study period. Mechanical valves were used in approximately 27% to 33% of cases, and the proportion of mechanical valve use showed a tendency to decrease, with marginal significance overall (p=0.078) and significant decreases in patients less than 60 years of age and in men (p=0.013 and p=0.023, respectively). The use of sutureless valves increased from 13.4% to 25.8% of cases (p<0.001), especially in elderly patients (>70 years) and those requiring concomitant surgery. In a comparison between sutureless and rapid deployment valves, the use of Perceval S valves (a type of sutureless valve), gradually increased (p<0.001). Conclusion: After the introduction of sutureless and rapid deployment valves in Korea, the rate of use of these new valves remarkably increased, especially in elderly patients and those requiring concomitant surgery. Further studies should investigate the clinical outcomes of these new prostheses.

Spatial and seasonal distributions of the phototrophic dinoflagellate Biecheleriopsis adriatica (Suessiaceae) in Korea: quantification using qPCR

  • Kang, Hee Chang;Jeong, Hae Jin;Ok, Jin Hee;You, Ji Hyun;Jang, Se Hyeon;Lee, Sung Yeon;Lee, Kyung Ha;Park, Jae Yeon;Rho, Jung-Rae
    • ALGAE
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    • v.34 no.2
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    • pp.111-126
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    • 2019
  • The phototrophic dinoflagellate Biecheleriopsis adriatica is a small suessioid species characterized by a fragile thin wall. Although the morphology of this dinoflagellate is well established, there is currently little information available on its distribution and the environmental factors that influence this distribution. Thus, to investigate the spatial and seasonal distributions of the vegetative cells of B. adriatica in Korean waters, surface water samples were collected on a seasonal basis from 28 stations in the East, West, and South Sea of Korea and Jeju Island from April 2015 to October 2018, and abundances of the vegetative cells of B. adriatica were quantified using quantitative real-time polymerase chain reactions, for which we developed the species-specific primer and probe set. Simultaneously, major environmental parameters, including temperature, salinity, nutrient concentrations, and dissolved oxygen concentrations were measured. The vegetative cells of B. adriatica were detected at 20 of the 28 sampling stations: 19 stations in summer and 6 in autumn, although from no stations in either spring or winter. The ranges of water temperature and salinity at sites where this species was detected were $17.7-26.4^{\circ}C$ and 9.9-34.3, respectively, whereas those of nitrate and phosphate concentrations were not detectable-96.2 and $0.18-2.66{\mu}M$, respectively. Thus, the sites at which this species is found are characterized by a narrow range of temperature, but wide ranges of salinity and concentrations of nitrate and phosphate. The highest abundance of the vegetative cells of B. adriatica was $41.7cells\;mL^{-1}$, which was recorded in Jinhae Bay in July 2018. In Jinhae Bay, the abundance of vegetative cells was significantly positively correlated with the concentration of nitrate, but was negatively correlated with salinity. On the basis of these findings, it appears that the abundance of B. adriatica vegetative cells shows strong seasonality, and in Jinhae Bay, could be affected by the concentrations of nitrate.

Variation in Planktonic Assemblages in Asan Bay During the Winter-Spring Bloom (아산만 해역 동-춘계 대증식기의 플랑크톤 변화)

  • Park, Chul;Lee, Doo-Byoul;Lee, Chang-Rae;Yang, Sung-Ryull;Jung, Byoung-Gwan
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.13 no.4
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    • pp.308-319
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    • 2008
  • Temporal variations in plankton assemblages and environmental factors in Asan Bay and their relationships were examined with the data collected from February till early June, 2005. Seawater temperatures showed typical pattern of temporal change observed in temperate waters. Salinity variation was minor. Phytoplankton biomass showed two peaks, one in February only in the inner part of the bay and the other in May in the whole bay. Phytoplankton succession was clearly shown with the increase of seawater temperatures. Diatom (Bacillariophyceae) dominated in February, diatom and cryptomonads (Cryptophyceae) prevailed in May, and dinoflagellates (Dinophyceae) was most abundant in June. Spring bloom in Asan Bay occurred about one month earlier than those observed in temperate seas. Among the inorganic nutrients (N, P and Si), only silicate concentration showed a significant negative correlation with phytoplankton biomass, indicating the sink of this nutrient in the bay to be the uptake by phytoplankton. Nitrate concentration seemed to be a limiting factor in this bay during the study period. Mesozooplankton abundances showed a significant positive correlation with seawater temperatures and a significant negative correlation with phytoplankton biomass. Increase of mesozooplankton abundance followed phytoplankton increase with the time lag of about two months. This increase of zooplankton seemed to be the result of increased seawater temperatures and food.

ROS- and pH-Responsive Polydopamine Functionalized Ti3C2Tx MXene-Based Nanoparticles as Drug Delivery Nanocarriers with High Antibacterial Activity

  • Wei-Jin Zhang;Shuwei Li;Veena Vijayan;Jun Seok Lee;Sung Soo Park;Xiuguo Cui;Ildoo Chung;Jaejun Lee;Suk-kyun Ahn;Jung Rae Kim;In-Kyu Park;Chang-Sik Ha
    • Nanomaterials
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    • v.12 no.24
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    • pp.4392-4416
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    • 2022
  • Premature drug release and poor controllability is a challenge in the practical application of tumor therapy, which may lead to poor chemotherapy efficacy and severe adverse effects. In this study, a reactive oxygen species (ROS)-cleavable nanoparticle system (MXene-TK-DOX@PDA) was designed for effective chemotherapy drug delivery and antibacterial applications. Doxorubicin (DOX) was conjugated to the surface of (3-aminopropyl)triethoxysilane (APTES)-functionalized MXene via an ROS-cleavable diacetoxyl thioketal (TK) linkage. Subsequently, the surfaces of the MXene nanosheets were coated with pH-responsive polydopamine (PDA) as a gatekeeper. PDA endowed the MXene-TK-DOX@PDA nanoparticles with superior biocompatibility and stability. The MXene-TK-DOX@PDA nanoparticles had an ultrathin planar structure and a small lateral size of approximately 180 nm. The as-synthesized nanoparticles demonstrated outstanding photothermal conversion efficiency, superior photothermal stability, and a remarkable extinction coefficient (23.3 L g-1 cm-1 at 808 nm). DOX exhibited both efficient ROS-responsive and pH-responsive release performance from MXene-TK-DOX@PDA nanoparticles due to the cleavage of the thioketal linker. In addition, MXene-TK-DOX@PDA nanoparticles displayed high antibacterial activity against both Gram-negative Escherichia coli (E. coli) and Gram-positive Bacillus subtilis (B. subtilis) within 5 h. Taken together, we hope that MXene-TK-DOX@PDA nanoparticles will enrich the drug delivery system and significantly expand their applications in the biomedical field

A Macroblock-Layer Rate Control for H.264/AVC Using Quadratic Rate-Distortion Model (2차원 비트율-왜곡 모델을 이용한 매크로블록 단위 비트율 제어)

  • Son, Nam-Rae;Lee, Guee-Sang;Yim, Chang-Hoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.9C
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    • pp.849-860
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    • 2007
  • Because the H.264/AVC standard adopts the variable length coding algorithm, the rate of encoded video bitstream fluctuates a lot as time flows, though its compression efficiency is superior to that of existing standards. When a video is transmitted in real-time over networks with fixed low-bandwidth, it is necessary to control the bit rate which is generated from encoder. Many existing rate control algorithms have been adopting the quadratic rate-distortion model which determines the target bits for each frame. We propose a new rate control algorithm for H.264/AVC video transmission over networks with fixed bandwidth. The proposed algorithm predicts quantization parameter adaptively to reduce video distortion using the quadratic rate-distortion model, which uses the target bit rate and the mean absolute difference for current frame considering pixel difference between macroblocks in the previous and the current frame. On video samples with high motion and scene change cases, experimental results show that (1) the proposed algorithm adapts the encoded bitstream to limited channel capacity, while existing algorithms abruptly excess the limit bit rate; (2) the proposed algorithm improves picture quality with $0.4{\sim}0.9dB$ in average.