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Use of Quantitative Vertebral Bone Marrow Fat Fraction to Assess Disease Activity and Chronicity in Patients with Ankylosing Spondylitis

  • Ga Young Ahn;Bon San Koo;Kyung Bin Joo;Tae-Hwan Kim;Seunghun Lee
    • Korean Journal of Radiology
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    • v.22 no.10
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    • pp.1671-1679
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    • 2021
  • Objective: We quantitatively measured the fat fraction (FF) in the vertebrae of patients with ankylosing spondylitis (AS) using magnetic resonance imaging (MRI) and investigated the role of FF as an indicator of both active inflammation and chronicity. Materials and Methods: A total of 52 patients with AS who underwent spinal MRI were retrospectively evaluated. The FF values of the anterosuperior and anteroinferior corners of the bone marrow in the L1-S1 spine were assessed using the modified Dixon technique. AS activity was measured using the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), AS Disease Activity Score (ASDAS), and serum inflammatory marker levels. AS disease chronicity was assessed by AS disease duration and the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS). Univariable and multivariable regression analyses were conducted to investigate the correlation between FF and other clinical characteristics. Results: The mean FF ± standard deviation of the total lumbar spine was 43.0% ± 11.3%. At univariable analysis, spinal FF showed significant negative correlation with BASDAI (β = -0.474, p = 0.002) and ASDAS with C-reactive protein (ASDAS-CRP; β = -0.478, p = 0.002) and a significant positive correlation with AS disease duration (β = 0.440, p = 0.001). After adjusting for patient age, sex, and total mSASSS score, spinal FF remained significantly negatively correlated with BASDAI (β = -0.543, p < 0.001), ASDAS-CRP (β = -0.568, p < 0.001), and ASDAS with erythrocyte sedimentation rate (β = -0.533, p = 0.001). Spinal FF was significantly lower in patients with very high disease activity (ASDAS-CRP > 3.5) than in those with only high disease activity (2.1 ≤ ASDAS-CRP ≤ 3.5) (p = 0.010). Conclusion: Spinal FF may help assess both AS disease activity and chronicity.

The Effects of Mask Covers on the Fit Factorsof Respirators (호흡보호구에서 마스크커버가 밀착계수에 미치는 영향)

  • Han, Don-Hee
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.23 no.3
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    • pp.177-183
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    • 2013
  • Objectives: 본 연구는 호흡보호구의 밀착도의 척도인 밀착계수 (FF)를 이용하여마스크에 마스크 커버를 씌웠을 때 호흡보호구의 밀착에 어떠한 영향을 미치는지 평가하고자 하였다. Methods: 3개 회사의 호흡보호구 (1개 1/4형, 2개 반면형)를 선정하여25의 피검자 (남자 16, 여자 9)에게 마스크 커버를 씌우지 않은 마스크와 씌운 마스크를 착용하게 하고 정량적인 밀착도 검사 (QNFT)를 실시하여 밀착계수 (FF)를 측정하였다. 동일한 조건에서 각 피검자에게 3번의 QNFT를 실시였으므로 한 마스크 당 씌운 것 75회, 씌우지 않은 것 75회, 150회를 시행하여 비교하였고 3개 마스크에 총 450회를 시행하였다. Results: 마스크 A (반면형)는 예상과는 다르게 마스크 커버가 있는 경우가 없는 경우보다 FF값이 더 높게 나왔으며 (p<0.05), 마스크 B (1/4형)와 마스크 C (반면형)은 마스크 커버가 없는 경우가 있는 경우보다 FF가 높게 나왔다. 마스크 B는 마스크 커버와 관계없이 FF가 너무 낮아 밀착에 문제가 있다고 판단되었으며 반대로 마스크 C는 마스크 커버에 영향을 받았으나 FF가 매우 높게 나와 밀착에는 큰 문제가 없다고 판단되었다. Conclusions: 본 연구 결과는 마스크에 자신의 마스크 커버를 씌울 경우 밀착에 큰 영향은 없는 것으로 나타났으나 FF만 가지고 실험했기 때문에 제한적이며 실제 작업현장에서 밀착도에 영향을 주지 않는지를 결정하기 위해서는 작업장보호계수 (WPF)를 이용한 보다 많은 연구가 필요하다.

Effects of force fields for refining protein NMR structures with atomistic force fields and generalized-Born implicit solvent model

  • Jee, Jun-Goo
    • Journal of the Korean Magnetic Resonance Society
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    • v.18 no.1
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    • pp.24-29
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    • 2014
  • Atomistic molecular dynamics (MD) simulation has become mature enabling close approximation of the real behaviors of biomolecules. In biomolecular NMR field, atomistic MD simulation coupled with generalized implicit solvent model (GBIS) has contributed to improving the qualities of NMR structures in the refinement stage with experimental restraints. Here all-atom force fields play important roles in defining the optimal positions between atoms and angles, resulting in more precise and accurate structures. Despite successful applications in refining NMR structure, however, the research that has studied the influence of force fields in GBIS is limited. In this study, we compared the qualities of NMR structures of two model proteins, ubiquitin and GB1, under a series of AMBER force fields-ff99SB, ff99SB-ILDN, ff99SB-NMR, ff12SB, and ff13-with experimental restraints. The root mean square deviations of backbone atoms and packing scores that reflect the apparent structural qualities were almost indistinguishable except ff13. Qualitative comparison of parameters, however, indicates that ff99SB-ILDN is more recommendable, at least in the cases of ubiquitin and GB1.

Effects of Forsythiae Fructus, Ulmi Cortex and JwaGwiEum in Allergic Rhinitis Induced by Ovalbumin in Mice (난알부민으로 유발된 생쥐의 알레르기 비염에 연교, 유근피, 좌귀음이 미치는 영향)

  • Kim, Bit Na Rae
    • The Journal of Pediatrics of Korean Medicine
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    • v.31 no.2
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    • pp.34-47
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    • 2017
  • Objectives In the past, studies have been shown that Forsythiae Fructus (FF), Ulmi Cortex (UC) and JwaGwiEum (JGE) are effective in treating allergic reactions. However, no report shows the difference in effects of FF, UC and JGE in allergic rhinitis (AR). Therefore, the purpose of this study was to differentiate the effects of FF, UC and JGE in AR induced by ovalbumin (OVA) in mice. Methods From this experiment, the effects of FF, UC and JGE were several - changes in body weight, hematologic changes such as WBC, RBC, Hb and PLT counts, immunological changes such as levels of histamine, IgE, IL-4 and expressions of iNOS & COX-2 mRNA. Moreover, histological change of nasal mucosa was also investigated. Results FF administration group and JGE administration group significantly inhibited level of IgE compared to the control group. Also, FF administration group, UC administration group and JGE administration group inhibited IL-4 and expressions of iNOS & COX-2 mRNA. In histological assessment, FF administration group, UC administration group and JGE administration group showed reduced amount of subepithelial edema, desquamated mucosa and hyperplasia of basement membrane from OVA.

Realization for FF-PID Controlling System with Backward Propagation Algorithm (역전파 알고리즘을 이용한 FF-PID 제어 시스템 구현)

  • Ryu, Jae-Hoon;Hur, Chang-Wu;Ryu, Kwang-Ryol
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2007.06a
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    • pp.171-174
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    • 2007
  • A realization for FF-PID(Feed-Forward PID) controlling system with backward propagation algorithm and image pattern recognition is presented in this paper. The pattern recognition used backward propagation of nervous network is teaming. FF-PID is enhanced the response characteristic of moving image by using the controlling value which is output error for the target value of nervous system. In conclusion of experiment, the system is shown that the response is worked as 2.7sec that is enhanced round 15% in comparison with general difference image algorithm. The system is able to control a moving object with effect.

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PCRAM Flip-Flop Circuits with Sequential Sleep-in Control Scheme and Selective Write Latch

  • Choi, Jun-Myung;Jung, Chul-Moon;Min, Kyeong-Sik
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.13 no.1
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    • pp.58-64
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    • 2013
  • In this paper, two new flip-flop circuits with PCRAM latches that are FF-1 and FF-2, respectively, are proposed not to waste leakage during sleep time. Unlike the FF-1 circuit that has a normal PCRAM latch, the FF-2 circuit has a selective write latch that can reduce the switching activity in writing operation to save switching power at sleep-in moment. Moreover, a sequential sleep-in control is proposed to reduce the rush current peak that is observed at the sleep-in moment. From the simulation of storing '000000' to the PCRAM latch, we could verify that the proposed FF-1 and FF-2 consume smaller power than the conventional 45-nm FF if the sleep time is longer than $465{\mu}s$ and $95{\mu}s$, respectively, at $125^{\circ}C$. For the rush current peak, the sequential sleep-in control could reduce the current peak as much as 77%.

Effect of Zinc-enriched Yeast FF-10 Strain on the Alcoholic Hepatotoxicity in Alcohol Feeding Rats

  • Cha, Jae-Young;Heo, Jin-Sun;Cho, Young-Su
    • Food Science and Biotechnology
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    • v.17 no.6
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    • pp.1207-1213
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    • 2008
  • The possible protective effects of highly zinc-containing yeast Saccharomyces cerevisiae, FF-10 strain, isolated from tropical fruit rambutan on acute alcoholic liver injury in rats were evaluated. Zinc concentration in this strain was 30.6mg%. The activities of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and $\gamma$-glutamyl transpeptidase ($\gamma$-GTP) were highly increased when alcohol was treated, relative to the normal rats. Also, a highly significant increase in the blood alcohol and acetaldehyde levels by alcohol treatment was observed. Administration of FF-10 strain markedly prevented alcohol-induced elevation of the activities of serum ALT, AST, and $\gamma$-GTP, and the levels of blood alcohol and acetaldehyde, and these reduced levels reached to that of normal rats. As compared with alcohol treated control rats, the FF-10 strain supplementation showed highly decreased the triglyceride concentration in serum. Alcohol treatment induced the marked accumulation of small lipid droplets, hepatocytes necrosis, and inflammation, but FF-10 strain administration attenuated to alcohol-induced accumulation of small lipid droplets and hepatocyte necrosis in the liver. Therefore, the current finding suggests that zinc-enriched yeast FF-10 strain isolated from tropical fruit rambutan may have protective effect against alcohol-induced hepatotoxicity.

Process Development and Economic Evaluation for Catalytic Conversion of Furfural to Tetrahydrofurfuryl Alcohol (푸르푸랄의 화학적 촉매전환을 통한 테트라히드로푸르푸릴 알코올 생산 공정 개발 및 경제성 평가)

  • Byun, Jaewon;Han, Jeehoon
    • Korean Chemical Engineering Research
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    • v.55 no.5
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    • pp.609-617
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    • 2017
  • Lignocellulosic biomass is a renewable resource for production of biofuels and biochemicals. Furfural (FF) is an important platform chemical catalytically derived from the hemicellulose fraction of biomass. Tetrahydrofurfuryl alcohol (THFA) is a FF derivative and can be used as an eco-friendly solvent with thermal and chemical stability. Despite large numbers of experimental studies for catalytic conversion of FF to THFA, few research have conducted on the economic feasibility for large-scale THFA production from FF. At the stage of assessment of the potential for commercialization of conversion technology, a large-scale process study is required to identify technological bottleneck and to obtain information for solving scale-up problems. In this study, process simulation and technoeconomic evaluation for catalytic conversion of FF to THFA are performed, as the following three steps: integrated process design, heat integration, and economic evaluation. First, a large-scale process including conversion and separation processes is designed based on experimental results. When the FF processing rate is 255 tonnes per day, the FF-to-THFA yields are 63.2~67.9 mol%. After heat integration, the heating requirements are reduced by 14.4~16.4%. Finally, we analyze the cost drivers and calculate minimum selling price of THFA by economic evaluation. The minimum selling price of THFA for the developed process are $2,120~2,340 per tonne, which are close to the current THFA market price.

Antioxidative Activity of Zinc-Enriched Saccharomyces cerevisiae FF-10 in In vitro Model Systems (아연-고함유 효모 Saccharomyces cerevisiae FF-10 세포액의 항산화효과)

  • Cha, Jae-Young;Park, Bo-Kyung;Ahn, Hee-Young;Eom, Kyung-Eun;Jun, Bang-Sil;Cho, Young-Su
    • Journal of Life Science
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    • v.19 no.2
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    • pp.179-184
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    • 2009
  • Zinc is an essential trace element for human and plays an important biological role in antioxidant properties. We have been reported that zinc-enriched S. cerevisiae FF-10 contained 392 mg% in the YM basal and 3,193 mg% in the YM optimal medium. Antioxidative activity of FF-10 was tested in vitro models by DPPH (${\alpha},{\alpha}'$-diphenyl-${\beta}$-picrylhydrazyl) radical scavenging activity and lipid peroxidation using linoleic acid (LA) and rat liver homogenate. DPPH radical scavenging activity was higher in the cell-free extract of FF-10 cultured in the YM optimal medium (YMOM) than that in the YM basal medium (YMBM). The inhibition activity of lipid peroxidation using rat liver homogenate was shown in the following order: BHT > YMOM > YMBM and these values were dose dependently. The lipid peroxidation of the control mixture by ferric thiocyanate and TBA methods using LA was increased rapidly as typical peroxidation curve of LA from one day and the antioxidation activity of the cell free extracts by cultivating FF-10 in the YMOM were higher than that of the YMBM. Result of this study indicate that the cell-free extracts containing a high intercellular zinc of S. cerevisiae FF-10 cultured in YMOM showed strong antioxidation capacities in DPPH radical scavenging activity and lipid peroxidation using LA and rat liver homogenate.

Effects of Cumulus Cells and Follicular Fluid on Plasminogen Activator Activity during In Vitro Maturation of Porcine Oocytes

  • Ann Ji-Young;Sa Soo-Jin;Cao Yang;Lee Sang-Young;Cheon Hee-Tae;Yang Boo-Keun;Park Choon-Keun
    • Reproductive and Developmental Biology
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    • v.30 no.2
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    • pp.135-141
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    • 2006
  • The present study was conducted to investigate the effects of cumulus cells and porcine follicular fluid (pFF) on plasminogen activator (PA) activity and oocytes maturation in vitro in the pig. The cumulus-oocyte complexes (COCs) and denuded oocytes (DOs) were incubated in NCSU-23 medium with or without 10% pFF for 0, 24, or 48 hr. In the presence of cumulus cells, the proportions of oocytes matured to metaphase-II stage were significantly (P<0.05) higher in medium with pFF than without pFF (69.8 vs. 37.7%, respectively). When COCs and DOs were cultured in the presence of pFF, tissue-type PA (tPA), urokinase-type PA (uPA), and tPA-PA inhibitor (tPA-PAI) were observed in COCs, and PA activities were higher at 48 hr than 24 hr. When COCs and DOs were cultured in the absence of pFF, tPA and tPA-PAI were observed in COCs, and PA activities were increased as duration of culture increased. No PA activities were detected in DOs regardless of pFF supplementation. When porcine oocytes were cultured in the presence of pFF for 24 and 48 hrs, the activities of tPA-PAI, tPA, and uPA were observed in both COCs and DOs. In medium of absence of pFF, PA activities were observed in oocytes with cumulus cells only. On the other hand, three plasminogen-dependent lytic bands (tPA-PAI, tPA, and uPA) were observed in pFF cultures. Particularly uPA activity was higher than the other kinds of PA activity. When oocytes and cumulus cells were separated from porcine COCs at 0 hr of culture, tPA-PAI, tPA, and uPA were detected in cumulus cells at 48 hr of culture, but no PA activities were in DOs. The presence of pFF and cumulus cells in maturation medium stimulated not only nuclear and cytoplasmic maturation in porcine COCs, but also PA production by cumulus cells and COCs. It is possible that PAs produced by cumulus cells migrated through the gap junction between oocyte and cumulus cells. These results suggest that porcine oocytes have no ability to produce PA themselves.