• Title/Summary/Keyword: Rate Limiting

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Hypopigmentary Effects of Dipeptides in B16 Melanoma Cells (디펩타이드의 B16 악성흑색종세포에서 멜라닌 생성억제작용)

  • Nam, Hee-Seung;Kim, Eun-Hyun;Kim, Su-Yeon;Lee, Hyun-E;Hong, Ji-Yun;Lee, Jae-Guk;Cho, Sung-Tai;Cho, Yang-Hwan;Yun, Hye-Young;Baek, Kwang-Jin;Kwon, Nyoun-Soo;Min, Young-Sil;Park, Kyoung-Chan;Kim, Dong-Seok
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.38 no.1
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    • pp.67-73
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    • 2012
  • In the present study, we investigated the effects of dipeptides on melanogenesis in B16 melanoma cells. It was found that WV (Trp+Val), WM (Trp+Met), and CQ (Cys+Gln) decreased melanin production dosedependently. However, dipeptides did not directly inhibit tyrosinase activity, the rate-limiting melanogenic enzyme. Therefore, we further investigated the expression of tyrosinase. Our results showed that ${\alpha}$-MSH-induced tyrosinase expression was down-regulated by WV, WM, and CQ. Thus, we propose that WV, WM, and CQ show hypopigmentary activity through tyrosinase down-regulation.

Nitrogen Removal in Column Wetlands Packed with Synthetic Fiber Treating Piggery Stormwater (축산단지 강우 유출수 처리를 위한 합성섬유충진 습지의 질소제거에 관한 연구)

  • Cheng, Jing;Kim, Youngchul
    • Journal of Wetlands Research
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    • v.18 no.1
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    • pp.68-75
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    • 2016
  • A set of lab-scale polymer synthetic fiber packed column wetlands composing three columns (CW1, CW2 and CW3) with different hydraulic regimes, recirculation frequencies and pollutant loading rates, were operated in 2012. Synthetic fiber tested as an alternative wetland medium for soil mixture or gravel which has been widely used, has very high pore size and volume, so that clogging opportunity can be greatly avoided. The inflow to the wetland was artificial stormwater. All the wetlands achieved effective removal of TSS (94%~96%), TCOD (68%~73%), TN (35%~58%), TKN (62%~73%) and NH4-N (85%~ 99%). Particularly, it was observed that COD was released from the fiber during one distinct period in all wetlands. This was probably due to the degradation of polymer fiber, and the released organic matters were found to serve as carbon source for denitrification. In addition, with longer retention time and frequent recirculation, lower effluent concentration was observed. With higher pollutant loading rate, higher nitrification and denitrification rates were achieved. However, although organic matters were released from the fiber, the lack of carbon source was still the limiting factor for the system since the release persisted only for 40 days.

A Study on the Perstraction Process Using Microporous Hollow Fiber -The Characteristics of Perstraction Using PP and Hollow Fiber- (다공성 실관막을 이용한 투과추출 공정에 관한 연구 -PP 및 PTFE실관막을 이용한 에탄올의 투과추출 특성에 관한 연구-)

  • Cheong, Won;Hwang, Eui-Yoon;Lee, Ho-Won;Kim, Woo-Sik
    • Membrane Journal
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    • v.1 no.1
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    • pp.65-77
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    • 1991
  • The perstraction of ethanol and acetic acid were performed for three systems of xylene-acetic acid-water, MIBK-ethanol-water, and TBP-ethanol-water, The operating variables were pressure difference between aqueous and organic phase, and superfial velocities of aqueous and organic phases. The tortuosities of PP hollow fiber membrane of Celgard X10-400 and PTFE hollow fober membrane of Tex TA001 were found to be 1.82 and 1.43 respectively, They were obtained from mass tranfer coeffidents in membrane phase for xylene-acetic acid-water systems. The permeation flux and overall mass transfer coefficient for MIBK-ethanol-water system are larger than those for TBP-ethanol-water system. This tendency is magnified with increasing the superficial velocity of organic phase. Overall mass transfer coefficient($K_o$) increases nonlinearly with the increase of superficial velocity of organic phase($V_{or}$), and the relationship between $K_o$ and $V_{or}$ is that $K_o {\propto} V_{or}^{-0.35}$. For ethanol perstraetion using the hollow fiber membrane of Gore Tex TA001, the mass transfer in membrane phase is the rate-limiting step.

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A Study for Development of Ratio Beale Measuring Pain Using Korean Pain Tersm (통증어휘를 이용한 통증비율척도의 개발연구)

  • 이은옥;윤순녕;송미순
    • Journal of Korean Academy of Nursing
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    • v.14 no.2
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    • pp.93-111
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    • 1984
  • The main purpose of this study is to develop a ratio scale measuring level of pain using Korean pain terms. The specific purposes of this study are to identify the degree of pain of each pain term in each subclass: to classify each subclass in terms of dimensions of pain; and to analyze factors of the Korean pain ratio scale clustering together. One hundred an4 fifty eight pain terms which were originally identified as representative terms and their synonyms were used for data collection. Fifty eight nursing professors ana sixty one medical doctors who have contacted with patients having pain were asked to rate the weight of each pain term on a visual analogue scale. Subclasses in which ranks of pain terms were same f s findings in two previous studies were 1) thermal 3 am 2) cavity pressure, 3) single stimulating pain, 4) radiation pain. and 5) chemical pain. Subclasses in which ranks of pain terms were confused were 1) incisive pressure, and 2) cold pain. Subclasses in which one new pain term was added were 1) inflammatory-repeated pain, 2) punctuate pressure, 3) constrictive pressure, 4) fatigue-related pressure, and 5) suffering-relate4 pain. Subclasses in which two new pain terms were added were 1) traction pressure, 2) peripheral nerve pain, 3) dull pain, 4) pulsation-related pain, 5) digestion-related pain, 6) tract pain, and 7) punishment-related pain. Subclass in which 3 new pain terms were included was fear-related pain. Rating scores of 5 words in 4 subclasses were significantly different between the normal group and the extreme group of subjects in terms of subjective rating. Only one word among 6 words was that newly added to the scale. Rating scores of 12 words in 9 subclasses were significantly different between doctor group and nursing professor group. Among these 12 words, only 3 were those newly added to the scale. In comparison of these 12 words, mean scores of the nursing professors were always 7 to 16 points higher than those of the medical doctors. In the analysis of judgement of subjects in terms of dimensions of pain terms, subclasses of dull pain, cavity pressure, tract pain and cold pain were suggested to be included in the miscellaneous dimension. As a result of factor analysis of the ratings given to 96 pain words using principal components analysis without iteration and with varimax rotation limiting the number of factors to 4, factors of severe pain (factor I) mild-moderate pain (factor II) , causative pain (factor III) and temperature-related pain(factor IV) were extracted with the factor loading above 0.388. When the pain words were re-arranged on the bases of factor loading above 0.368, number of factors decreased to only first two factors. Maximum score of pain word in factor II was 46.17 and the minimum score of the factor I was 45.36. Further studies are needed to identify the validity, reliability, sensitivity and practicability of this ratio scale using patients having various sources of pain.

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Family-Based Association Study of Tryptophan-2,3 Dioxygenase(TDO2) Gene and Autism Spectrum Disorder in the Korean Population (한국인 자폐 스펙트럼장애에서 Tryptophan 2,3 Dioxygenase(TDO2)유전자 다형성-가족 기반 연구)

  • Kim, Soon-Ae;Park, Mi-Ra;Cho, In-Hee;Yoo, Hee-Jeong
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.18 no.2
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    • pp.123-129
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    • 2007
  • Objectives: Autism is a complex neurodevelopmental spectrum disorder with a strong genetic component. Previous neurochemical and genetic studies have suggested the possible involvement of the serotonin system in autism. Tryptophan 2,3-dioxygenase(TDO2) is the rate-limiting enzyme in the catabolism of tryptophan, which is the precursor of serotonin synthesis. The aim of this study was to investigate the association between the TDO2 gene and autism spectrum disorders(ASD) in a Korean population. Methods: The patients were diagnosed with ASD on the basis of the DSM-IV diagnostic classification outlined in the Korean version of the Autism Diagnostic Interview-Revised and Autism Diagnostic Observation Schedule. The present study included the detection of four single nucleotide polymorphisms(SNPs) in the TDO2 gene(rs2292536, rs6856558, rs6830072, rs6830800) and the family-based association analysis of the single nucleotide polymorphisms in Korean ASD trios using a transmission disequilibrium test(TDT) and haplotype analysis. The family trios of 136 probands were included in analysis. 87.5% were male and 86.0% were diagnosed with autism. The mean age of the probands was $78.5{\pm}35.8$ months(range: 26-264 months). Results: Two SNPs showed no polymorphism, and there was no significant difference in transmission in the other two SNPs. We also could not find any significant transmission in the haplotype analysis(p>.05). Conclusion: We could not find any significant statistical association between the transmission of SNPs in the TDO2 gene and ASD in a Korean population. This result may not support the possible involvement of the TDO2 gene in the development of ASD, and further exploration might be needed to investigate other plausible SNP sites.

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Host plant preference, parasitic site and risk possibility of Cuscuta pentagona Engelm, invasive plant in Korea (침입종 미국실새삼(Cuscuta pentagona Engelm.)의 기주식물 선호도, 기생부위 및 위해가능성)

  • Jung, Young-Ho;Lee, Jae-Keun;Lee, Soo-In;Lee, Seung-yeon;Jang, Rae-Ha;Lee, Seung-Hyeok;Cho, Kyu-Tae;You, Young-Han
    • Korean Journal of Environment and Ecology
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    • v.31 no.3
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    • pp.287-296
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    • 2017
  • In order to check host plant diversity and to confirm the potential risk to be invaded, we documented host plant flora and plant part of C. pentagona, an invasive parasitic plant in field survey and induced parasitic infection by them in the laboratory experiment. Parasitic interaction(12% of total tree species) was found in twig and leaf of tree such as Quercus mongolica and Abies holophylla that was not developed into ligninfication. There were most host plant species belong to Compositae, but the species parasitic rate of family was higher in Cyperaceae, Polygonaceae and Leguminoceae. Through the inducible infection experiment with C. pentagona, all species except one species show parasitic interaction between host plan and C. pentagona. These result means that the limiting stage for invading area is dispersion process for invading other area in Korea. Infection plant part by C. pentagona was dominantly both shoot and leaf, rather than only leaf or only shoot. We found newly 12 families and 45 host plant species including 33 herbacious one and 12 woody one. Crop plant such as Setaria italica and 6 endangerd one such as Scrophularia takesimensis, especially the later rare endemic plant was to death by parasitic infection of C. pentagona. These results indicate that C. pentagona is potential risk to both wild and cultivated plant in Korea.

Mechanism Underlying the Anti-Inflammatory Action of Piceatannol Induced by Lipopolysaccharide (당지질로 유도한 염증반응에서 Piceatannol의 항염증 기전 연구)

  • Cho, Han-Jin;Shim, Jae-Hoon;So, Hong-Seob;YoonPark, Jung-Han
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.9
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    • pp.1226-1234
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    • 2012
  • 3,4,3',5'-Tetrahydroxy-trans-stilbene (piceatannol) is a derivative of resveratrol with a variety of biological activities, including anti-inflammatory, anti-proliferative, and anti-cancer activities. We assessed the mechanisms by which piceatannol inhibits inflammatory responses using lipopolysaccharide (LPS)-treated Raw264.7 murine macrophages. Piceatannol (0~10 ${\mu}mol/L$) decreased LPS-induced release of nitric oxide, tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-6, IL-$1{\beta}$, and inhibited LPS-induced protein expression of inducible nitric oxide synthase (iNOS). Activation of nuclear factor-kappaB (NF-${\kappa}B$), activator protein (AP)-1, and signal transducer and activator of transcription 3 (STAT3) are crucial steps during an inflammatory response. Piceatannol prevented LPS-induced degradation of inhibitor of ${\kappa}B$ ($I{\kappa}B$), translocation of p65 to the nucleus, and phosphorylation of stress-activated protein kinase/c-Jun NH2-terminal kinase (SAPK/JNK). Additionally, piceatannol inhibited LPS-induced phosphorylation of STAT3 and IL-6-induced translocation of STAT3 to the nucleus. Furthermore, piceatannol increased the protein and mRNA levels of hemeoxygenase (HO)-1, the rate-limiting enzyme of heme catabolism that plays a critical role in mediating antioxidant and anti-inflammatory effects. Piceatannol further induced antioxidant response elements (ARE)-driven luciferase activity in Raw264.7 cells transfected with an ARE-luciferase reporter construct containing the enhancer 2 and minimal promoter region of HO-1. These results suggest that piceatannol exerts anti-inflammatory effects via the down-regulation of iNOS expression and up-regulation of HO-1 expression.

Development of Seed Culture Using Soybean for Mass Production of Lovastatin with Aspergillus terreus ATCC 20542 Mutant (대두를 이용한 Lovastatin 대량생산용 Seed Culture의 제조기술)

  • Kim, Soo-Jung;Ko, Hee-Sun;Kim, Hyun-Soo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.5
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    • pp.666-670
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    • 2008
  • Lovastatin (Mevinolin, Monacolin K) is a well-known drug for the therapy of hypercholesterolemia. It is an important fungal secondary metabolite as it inhibits 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase, EC 1.1.1.34) which catalyzes a major rate-limiting step in the biosynthesis of cholesterol. Both soybeans and black soybeans with Aspergillus terreus ATCC 20542 mutant were used as the seed culture for the mass production of lovastatin. The production of lovastatin in soybean seed culture of Asp. terreus was twofold compared to that of black soybean seed culture. The effect of two different vessels (petri dish and Erlenmeyer flask) on lovastatin production was also studied. The production of lovastatin on petri dish was tenfold to that of Erlenmeyer flask. Furthermore, the most lovastatin production on rice bran was achieved when the soybean seed culture was treated by heat shock at $30^{\circ}C$ for 1 hour, representing 82% of HMG-CoA reductase inhibition in the koji extract. We estimated that the heat treated soybean seed culture could be a new method for the mass production of lovastatin.

The Comparative Study of Alveolar Bone Level and Root Form of the Mandibular Molar on Radiographic Image and Clinical Examination (방사선사진과 임상검사에서 하악 대구치 치근의 형태학적 구조 및 치조골 수준에 관한 비교연구)

  • Park, Jung-Bae;Chung, Chin-Hyung
    • Journal of Periodontal and Implant Science
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    • v.34 no.2
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    • pp.281-292
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    • 2004
  • Periodontal defects of the furcation are characterized by several inherent anatomic factors that can make successful periodontal therapy difficult and results unpredictable. The severity and rate of occurrence of periodontal disease are directly related to the location of the furcation relative to the cementa-enamel junction and anatomical form of the root by limiting the accessibility and effectiveness of the periodontal instrumentation. This study investigated the reliability and accuracy of panoramic radiograph diagnoses of the periodontal state of mandibular molars, particularly regarding the diagnosis of furcation area periodontal defects, treatment planning, and prognosis prediction. This study examined a total of 110 teeth belonging to 33 subjects (19 male, 14 female) presenting with incipient to moderate periodontitis 4-7mmpocket depth. The alveolar bone level, length and width of the root trunk, and root separation angle were measured using the panoramic radiograph and compared to the results taken directly by retracting a full-thickness flap. The results of the study are as follows: 1. Data regarding the alveolar bone level of the mandibular first molar showed that the directly taken surgical measurements resulted in $5.1{\pm}0.9mm$ that was slightly deeper than the corresponding panoramic measurement resulted in $4.8{\pm}0.8mm$, but these differences were statistically insignificant (p>0.05). 2. The data of the directly taken surgical measurement of the mandibular second molar $(5.1{\pm}1.1mm)$ was slightly deeper than the corresponding panoramic measurement $(4.7{\pm}1.2mm)$, but these differences were statistically insignificant (p>0.05). 3. The measured values of the length and width of the mandibular first molar root trunks were determined to be $4.1{\pm}0.6mm$ and $7.3{\pm}0.9mm$, respectively, while the values of the mandibular second molar root trunks were determined to be $4.6{\pm}1.3mm$ and $7.6{\pm}0.9mm$ respectively. The differences between these values were found to be statistically significant (p<0.01). 4. The measured values of the root separation angle showed that the mandibular first molars averaged $34.5{\pm}4.4^{\circ}$, while the mandibular second molars averaged $23.0{\pm}10.0^{\circ}$. The differences between these values were found to be statistically significant (p<0.01).

Molecular cloning and expression analysis of the first two key genes through 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway from Pyropia haitanensis (Bangiales, Rhodophyta)

  • Du, Yu;Guan, Jian;Xu, Ruijun;Liu, Xin;Shen, Weijie;Ma, Yafeng;He, Yuan;Shen, Songdong
    • ALGAE
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    • v.32 no.4
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    • pp.359-377
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    • 2017
  • Pyropia haitanensis (T. J. Chang et B. F. Zheng) N. Kikuchi et M. Miyata is one of the most commercially useful macroalgae cultivated in southeastern China. In red algae, the biosynthesis of terpenoids through 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway can produce a direct influence on the synthesis of many biologically important metabolites. In this study, two genes of cDNAs, 1-deoxy-D-xylulose-5-phosphate synthase (DXS) and 1-deoxy-D-xylulose-5-phosphate reductase (DXR), which encoding the first two rate-limiting enzymes among MEP pathway were cloned from P. haitanensis. The cDNAs of P. haitanensis DXS (PhDXS) and DXR (PhDXR) both contained complete open reading frames encoding polypeptides of 764 and 426 amino acids residues, separately. The expression analysis showed that PhDXS was significant differently expressed between leafy thallus and conchocelis as PhDXR been non-significant. Additionally, expression of PhDXR and its downstream gene geranylgeranyl diphosphate synthase were both inhibited by fosmidomycin significantly. Meanwhile, we constructed types of phylogenetic trees through different algae and higher plants DXS and DXR encoding amino acid sequences, as a result we found tree clustering consequences basically in line with the "Cavalier-Smith endosymbiotic theory." Whereupon, we speculated that in red algae, there existed only complete MEP pathway to meet needs of terpenoids synthesis for themselves; Terpenoids synthesis of red algae derivatives through mevalonate pathway came from two or more times endosymbiosis of heterotrophic eukaryotic parasitifer. This study demonstrated that PhDXS and PhDXR could play significant roles in terpenoids biosynthesis at molecular levels. Meanwhile, as nuclear genes among MEP pathway, PhDXS and PhDXR could provide a new way of thinking to research the problem of chromalveolata biological evolution.