• Title/Summary/Keyword: Production Mechanism

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Effects of the Constituents of Paeonia lactiflora Root on Arachidonate and NO Metabolism

  • Choi, Yong-Hwan;Gu, Lianyu;Kim, Yeong-Shik;Kang, Sam-Sik;Kim, Ju-Sun;Yean, Min-Hye;Kim, Hyun-Pyo
    • Biomolecules & Therapeutics
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    • v.14 no.4
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    • pp.216-219
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    • 2006
  • In order to establish the anti-inflammatory cellular mechanism of the paeony root(Paeonia lactiflora, Pall, Paeoniaceae), the constituents including paeoniflorin, albiflorin, (+)-catechin, paeonol, benzoic acid and methyl gallate were evaluated for their effects on arachidonate and NO metabolism. Among the compounds tested, only paeonol weakly inhibited cyclooxygenase-2-mediated $PGE_2$ production from LPS-treated RAW 264.7 cells. (+)-Catechin and methyl gallate weakly inhibited inducible nitric oxide synthase-mediated NO production from the same cell line. In particular, methyl gallate significantly inhibited 5-lipoxygenase from RBL-l cells with an $IC_{50}$ of 8.4 ${\mu}M$. These results suggest that the inhibition of these components on arachidonate and NO metabolism may contribute at least in part to anti-inflammatory mechanism of the paeony root.

Fouling mechanism and screening of backwash parameters: Seawater ultrafiltration case

  • Slimane, Fatma Zohra;Ellouze, Fatma;Amar, Nihel Ben
    • Environmental Engineering Research
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    • v.24 no.2
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    • pp.298-308
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    • 2019
  • This work deals with the membrane fouling mode and the unclogging in seawater ultrafiltration process. The identification of the fouling mechanism by modeling the experimental flux decline was performed using both the classical models of Hermia and the combined models of Bolton. The results show that Bolton models did not bring more precise information than the Hermia's and the flux decline can be described by one of the four Hermia's models since the backwash interval is ${\leq}60$ min. An experimental screening study has been then conducted to choose among 5 parameters (backwash interval, duration, pulses and the flow-rate or injected hypochlorite concentration) those that are the most influential on the fouling and the net water production. It has emerged that fouling is mainly affected by the backwash interval; its prolongation from 30 to 60 min engenders an increase in the reversible fouling and a decrease in the irreversible fouling. This later is also significantly reduced when the hypochlorite concentration increases from 4.5 to 10 ppm. Moreover, the net water production significantly increases with increasing the filtration duration up to 60 min and decreases with decreasing the backwash duration and backwash flow-rate from 10 to 40 s and from 15 to ${\geq}20L.min^{-1}$, respectively.

Undaria pinnatifida Inhibits the Mast Cell-Mediated Inflammatory Response via NF-κB/Caspase-1 Suppression

  • Jeon, Yong-Deok;Lee, Su-Hyun;Kim, Su-Jin
    • Korean Journal of Plant Resources
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    • v.34 no.6
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    • pp.503-509
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    • 2021
  • Marine sources as potential treatment options for various diseases have been a subject of growing interest. However, information on the anti-inflammatory mechanism employed by Undaria pinnatifida (UP) remains limited. The present study was conducted to investigate the mechanisms of UP on the mast cell-mediated inflammatory response. To determine the pharmacological mechanism of UP in inflammatory reaction, we evaluated the effects of UP on interleukin (IL)-6, IL-8 and tumor necrosis factor (TNF)-α production and nuclear factor-κB (NF-κB) and caspase-1 activation in calcium ionophore A23187 plus phorbol 12-myristate 13-acetate-stimulated human mast cells-1 (HMC-1). The results showed that UP suppressed IL-6, IL-8 and TNF-α production in a dose-dependent manner. Moreover, UP significantly attenuated NF-kB/caspase-1 activation in stimulated HMC-1. Collectively, these findings provide experimental evidence that UP may be a useful candidate for the inflammation-related diseases treatment.

Inhibitory Effect of Persimmon Leaves on Melanin Synthesis and its Action Mechanism in B16F10 cells (시엽(枾葉)의 멜라닌 생성 억제와 작용기전에 관한 연구)

  • Jang, Du-Hyun;Yoo, Dong-Youl
    • The Journal of Korean Obstetrics and Gynecology
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    • v.22 no.2
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    • pp.43-59
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    • 2009
  • Purpose: This study was performed to determine the inhibitory effect of Persimmon Leaves extract (PL) on melanin synthesis in B16F10 melanoma cells B16F10. Methods: The inhibitory effects of PL on melanin synthesis were determined by in vitro assay. To elucidate inhibitory effects of PL on melanin synthesis, we determined the melanin release and melanin production in B16F10. And to investigate the action mechanism, we assessed the gene expression of tyrosinase, TRP-1, TRP-2, PKA, PKC${\beta}$, ERK-1, ERK-2, AKT-1, MITF in B16F10. Results: 1. PL inhibited melanin release, melanin production in B16F10. 2. PL inhibited tyrosinase activity in vitro and in B16F10. 3. PL suppressed the expression of tyrosinase, TRP-1, TRP-2 in B16F10. 4. PL suppressed the expression of PKA, PKC${\beta}$ in B16F10. 5. PL increased the expression of ERK-1, ERK-2, AKT-1 in B16F10. 6. PL suppressed the expression of MITF in B16F10. Conclusion: From these results, it may be concluded that PL is possesed of the antimelanogenetic effects.

A Model with an Inference Engine for a Fuzzy Production System Using Fuzzy Petri Nets (Fuzzy Petri Nets를 이용한 퍼지 추론 시스템의 모델링 및 추론기관의 구현)

  • ;Zeung Nam Bien
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.29B no.7
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    • pp.30-41
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    • 1992
  • As a general model of rule-based systems, we propose a model for a fuzzy production system having chaining rules and an inference engine associated with the model. The concept of so-called 'fuzzy petri nets' is used to model the fuzzy production system and the inference engine is designed to be capable of handling inexact knowledge. The fuzzy logic is adopted to represent vagueness in the rules and the certainty factor is used to express uncertainty of each rules given by a human expert. Parallel, inference schemes are devised by transforming Fuzzy Petri nets to matrix formula. Futher, the inference engine mechanism under the Mamdani's implication method can be desceribed by a simple algebraic formula, which makes real time inference possible.

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Regulation of Tubercidin Biosynthesis in Streptomyces tubercidicus by Adenine and Histidine (Streptomyces tubercidicus에서 Adenine과 Histidine에 의한 Tubercidin 생합성 조절)

  • 유진철;하영칠
    • Korean Journal of Microbiology
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    • v.29 no.3
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    • pp.160-166
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    • 1991
  • The regulatory mechanism of tubercidin biosynthesis in Streptomyces tubercidicus was studied. In a wild type strain, addition of adenine and histidine into the medium decreased the tubercidin production by 60-65% and 40%, respectively. The effects of adenine and histidine were alleviated by the addition of inosine monophosphate and 5-aminoimidazole-4-carboxamide ribotide. The production of tubercidin in S. tubercidicus K115 strain ($ade^{-}$ ) was nearly shut off by histidine. In contrast with K115 strain, adenine inhibited the tubercidin biosynthesis in S. tubercidicus K412 strain ($his^{-}$. In S. tubercidicus F667 strain ($ade^{-}$ , $his^{-}$ ), tubercidin production was increased by adenine and histidine. From the effects of adenine and histidine on tubercidin biosynthesis in S. tubercidicus wild type and mutant strains, it became known that feedback control by adenine and histidine of biosynthetic pathwat for purine ribonucleotide and histidine are involved in the regulation of tubercidin biosynthesis.

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An Integrated Planning of Production and Distribution in Supply Chain Management using a Multi-Level Symbiotic Evolutionary Algorithm (다계층 공생 진화알고리듬을 이용한 공급사슬경영의 생산과 분배의 통합계획)

  • 김여근;민유종
    • Journal of the Korean Operations Research and Management Science Society
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    • v.28 no.2
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    • pp.1-15
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    • 2003
  • This paper presents a new evolutionary algorithm to solve complex multi-level integration problems, which is called multi-level symbiotic evolutionary algorithm (MEA). The MEA uses an efficient feedback mechanism to flow evolution information between and within levels, to enhance parallel search capability, and to improve convergence speed and population diversity. To show the MEA's applicability, It is applied to the integrated planning of production and distribution in supply chain management. The encoding and decoding methods are devised for the integrated problem. A set of experiments has been carried out, and the results are reported. The superiority of the algorithm's performance is demonstrated through experiments.

Evolvable Neural Networks Based on Developmental Models for Mobile Robot Navigation

  • Lee, Dong-Wook;Seo, Sang-Wook;Sim, Kwee-Bo
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.7 no.3
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    • pp.176-181
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    • 2007
  • This paper presents evolvable neural networks based on a developmental model for navigation control of autonomous mobile robots in dynamic operating environments. Bio-inspired mechanisms have been applied to autonomous design of artificial neural networks for solving practical problems. The proposed neural network architecture is grown from an initial developmental model by a set of production rules of the L-system that are represented by the DNA coding. The L-system is based on parallel rewriting mechanism motivated by the growth models of plants. DNA coding gives an effective method of expressing general production rules. Experiments show that the evolvable neural network designed by the production rules of the L-system develops into a controller for mobile robot navigation to avoid collisions with the obstacles.

Effect of ginseng and ginsenosides on melanogenesis and their mechanism of action

  • Kim, Kwangmi
    • Journal of Ginseng Research
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    • v.39 no.1
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    • pp.1-6
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    • 2015
  • Abnormal changes in skin color induce significant cosmetic problems and affect quality of life. There are two groups of abnormal change in skin color; hyperpigmentation and hypopigmentation. Hyperpigmentation, darkening skin color by excessive pigmentation, is a major concern for Asian people with yellowe-brown skin. A variety of hypopigmenting agents have been used, but treating the hyperpigmented condition is still challenging and the results are often discouraging. Panax ginseng has been used traditionally in eastern Asia to treat various diseases, due to its immunomodulatory, neuroprotective, antioxidative, and antitumor activities. Recently, several reports have shown that extract, powder, or some constituents of ginseng could inhibit melanogenesis in vivo or in vitro. The underlying mechanisms of antimelanogenic properties in ginseng or its components include the direct inhibition of key enzymes of melanogenesis, inhibition of transcription factors or signaling pathways involved in melanogenesis, decreasing production of inducers of melanogenesis, and enhancing production of antimelanogenic factor. Although there still remain some controversial issues surrounding the antimelanogenic activity of ginseng, especially in its effect on production of proinflammatory cytokines and nitric oxide, these recent findings suggest that ginseng and its constituents might be potential candidates for novel skin whitening agents.

Inhibition of nitric oxide and TNF-$\alpha$ production by propenone compound through blockaded of NF-$\kappa$B activation in cultured murine macrophages

  • Ju, Hye-Kyung;Lee, Eun-Kyung;Jahng, Yurng-Dong;Lee, Eung-Seok;Chang, Hyeun-Wook
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.156.2-157
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    • 2003
  • Lipopolysaccharide (LPS)-stimulated macrophages produced a large amounts of nitric oxide (NO) by inducible nitric oxide synthase (iNOS). This is an important mechanism in macrophages-induced septic shock and inflammation. In the present study, we tested a synthetic propenone compound, l-furan-2-yl-3-pyridin-2-yl-propenone (FPP-3) for its ability to inhibit the production of tumor necrosis factor-a (TNF-$\alpha$) and an inducible enzyme, iNOS, in the LPS-stimulated murine macrophage-like cell line, Raw264.7. FPP-3 consistently inhibited nitric oxide (NO) and TNF-$\alpha$ production in a dose dependent manner, with $IC_50$> values of 10.0 and 13.1 $\mu$M, respectively. (omitted)

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