• Title/Summary/Keyword: Inhibiting Factors

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Inhibitory effect of Nymphoides indica extract on α-MSH induced melanin synthesis (어리연꽃 추출물이 α-MSH 유도에 의한 멜라닌 생성 억제에 미치는 영향)

  • Kim, Dong-Hee;Kim, You-Ah;Yu, Jae-Myo;Park, Chae-Bin;Park, Byoung-Jun;Park, Tae-Soon
    • Journal of Applied Biological Chemistry
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    • v.60 no.4
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    • pp.327-332
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    • 2017
  • In this study, the whitening activity of Nymphoides indica extract in B16F10 cells were measured. Inhibition rate of tyrosinase from mushroom was 42% at $1,000{\mu}g/mL$. And inhibition of tyrosinase and melanin biosynthesis in B16F10 cells were 26 and 25% at $5{\mu}g/mL$, respectively. The expression levels of cAMP and protein kinase A (PKA), which are higher levels of melanin-related factors, were found to be decreased in a dose-dependent manner. In addition, the expression rate of protein and mRNA of tyrosinase, tyrosinase related protein 1 (TRP1), tyrosinase related protein 2 (TRP2) and microphthalmia associated transcription factor (MITF). In this study, it was confirmed that the N. indica extract effectively inhibited the activity of tyrosinase, TRP1, TRP2 and MITF as well as the activity of PKA by effectively inhibiting cAMP. Therefore, it was confirmed that the N. indica extract has high value as a functional material.

Corrosion Stability of Iron Artifacts after Treating with Water Treatment (수처리제를 사용한 철제유물의 부식 안정성 연구)

  • Jeong, Ji Hae
    • Journal of Conservation Science
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    • v.33 no.5
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    • pp.381-390
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    • 2017
  • Desalination is the main focus of the stabilization of iron artifacts. However, drawbacks such as re-corrosion are noted due to the uncertainty in the elimination of the corrosive factors and artifacts. Several studies have been carried out on the effects of corrosion inhibitors to overcome these shortcomings. In this study, the effects of type 3 water treatment on corrosion inhibitors were investigated. Surfaces of samples that contained film corrosion inhibitors on their surfaces were analyzed. The results revealed that the surface rust was removed from the sample of type 1 No. 2 that was mainly composed of phosphate. The average weight reduction rates of re-corrosion samples were 0.58, 0.03, and 0.07% for type 1 No. 2, type 2 No. 2, and type 3 No. 2 respectively. The changes in the $Cl^-$ ion, a corrosive agent were found to be 28.60, -4.08, and -1.94 ppm for type 1 No. 2, type 2 No. 2, and type 3 No. 2 respectively. The water-treated films were analyzed by X-ray photoelectron spectroscopy (XPS). It was found that type 2 No. 2 had less Fe the basis metal, than that in type 3 No. 2 indicating much better film. Moreover, Si content was higher in type 2 No. 2, based on the silicate content, than in type 3 No. 2. They are speculated to be the reason or the formation of a better film. Type 1 No. 2, which is mainly composed of phosphate, would be inappropriate as a metal artifact conservation treatment. It was determined that type 2 No. 2 and type 3 No. 2 water treatments, which are mainly composed of silicate, provided excellent corrosion inhibiting effects. Corrosion inhibitors could be used as emergency treatment agents during the excavation of iron artifacts.

Comparative Study on Biological Activities of Colored Potatoes, Hongyoung and Jayoung Cultivar (유색감자 홍영 및 자영 추출물의 생물학적 활성 비교)

  • Kang, Se-Chan; Choung, Myoung-Gun
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.53 no.2
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    • pp.233-238
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    • 2008
  • This experiment was conducted to enhance the colored potatoes utilization and to determine the biological activity of colored potato extracts. In order to understand the factors responsible for the potent anti-oxidant ability of colored potatoes, it has been evaluated for anti-oxidative activity using oxygen radical absorbance capacity (ORAC) assay. 'Hongyoung' extract was significant anti-oxidant activities in ORAC assay. About two-fold higher radical absorbance capacity was found in 'Hongyoung' compared to that in 'Jayoung'. The ability of 80% ethanol extracts from colored potatoes to influence the inhibitory activity of nitric oxide (NO) and nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) has also been investigated. The various therapeutic benefit claims in the new functional medicinal usage of colored potatoes ascribed to the phenolic compounds and anthocyanin. This result revealed that the extracts of colored potatoes are expected to be good candidate for development into sources of free radical scavenger or COX-2 inhibiting agents.

Glucose-6-phosphate dehydrogenase deficiency does not increase the susceptibility of sperm to oxidative stress induced by H2O2

  • Roshankhah, Shiva;Rostami-Far, Zahra;Shaveisi-Zadeh, Farhad;Movafagh, Abolfazl;Bakhtiari, Mitra;Shaveisi-Zadeh, Jila
    • Clinical and Experimental Reproductive Medicine
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    • v.43 no.4
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    • pp.193-198
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    • 2016
  • Objective: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzyme defect. G6PD plays a key role in the pentose phosphate pathway, which is a major source of nicotinamide adenine dinucleotide phosphate (NADPH). NADPH provides the reducing equivalents for oxidation-reduction reductions involved in protecting against the toxicity of reactive oxygen species such as $H_2O_2$. We hypothesized that G6PD deficiency may reduce the amount of NADPH in sperms, thereby inhibiting the detoxification of $H_2O_2$, which could potentially affect their motility and viability, resulting in an increased susceptibility to infertility. Methods: Semen samples were obtained from four males with G6PD deficiency and eight healthy males as a control. In both groups, motile sperms were isolated from the seminal fluid and incubated with 0, 10, 20, 40, 60, 80, and $120{\mu}M$ concentrations of $H_2O_2$. After 1 hour incubation at $37^{\circ}C$, sperms were evaluated for motility and viability. Results: Incubation of sperms with 10 and $20{\mu}M\;H_2O_2$ led to very little decrease in motility and viability, but motility decreased notably in both groups in 40, 60, and $80{\mu}M\;H_2O_2$, and viability decreased in both groups in 40, 60, 80, and $120{\mu}M\;H_2O_2$. However, no statistically significant differences were found between the G6PD-deficient group and controls. Conclusion: G6PD deficiency does not increase the susceptibility of sperm to oxidative stress induced by $H_2O_2$, and the reducing equivalents necessary for protection against $H_2O_2$ are most likely produced by other pathways. Therefore, G6PD deficiency cannot be considered as major risk factor for male infertility.

Protective Effect of Ginsenoside Rb1 on Hydrogen Peroxide-induced Oxidative Stress in Rat Articular Chondrocytes

  • Kim, Sok-Ho;Na, Ji-Young;Song, Ki-Bbeum;Choi, Dea-Seung;Kim, Jong-Hoon;Kwon, Young-Bae;Kwon, Jung-Kee
    • Journal of Ginseng Research
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    • v.36 no.2
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    • pp.161-168
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    • 2012
  • The abnormal maturation and ossification of articular chondrocytes play a central role in the pathogenesis of osteoarthritis (OA). Inhibiting the enzymatic degradation of the extracellular matrix and maintaining the cellular phenotype are two of the major goals of interest in managing OA. Ginseng is frequently taken orally, as a crude substance, as a traditional medicine in Asian countries. Ginsenoside $Rb_1$, a major component of ginseng that contains an aglycone with a dammarane skeleton, has been reported to exhibit various biological activities, including anti-inflammatory and anti-tumor effects. However, a chondroprotective effect of ginsenoside $Rb_1$ related to OA has not yet been reported. The purpose of this study was to demonstrate the chondroprotective effect of ginsenoside $Rb_1$ on the regulation of pro-inflammatory factors and chondrogenic genes. Cultured rat articular chondrocytes were treated with 100 ${\mu}M$ ginsenoside $Rb_1$ and/or 500 ${\mu}M$ hydrogen peroxide ($H_2O_2$) and assessed for viability, reactive oxygen species production, nitric oxide (NO) release, and chondrogenic gene expression. Ginsenoside $Rb_1$ treatment resulted in reductions in the levels of pro-inflammatory cytokine and NO in $H_2O_2$-treated chondrocytes. The expression levels of chondrogenic genes, such as type II collagen and SOX9, were increased in the presence of ginsenoside $Rb_1$, whereas the expression levels of inflammatory genes related to chondrocytes, such as MMP1 and MMP13, were reduced by approximately 50%. These results suggest that ginsenoside $Rb_1$ has potential for use as a therapeutic agent in OA patients.

Changes of the Cellularities in the Bronchoalveolar Lavage Fluid of the Experimental Silicosis (흰쥐규폐증에서 기관지 폐포 세척액내 세포변화)

  • Lim, Young;Yun, Im-Goung;Oh, Min-Hwa
    • Tuberculosis and Respiratory Diseases
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    • v.38 no.2
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    • pp.143-154
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    • 1991
  • Pneumconiosis is a sort of pulmonary fibrosis consequent to the inhalation of the respirable dusts. Thus, the pathogenesis of silicosis have concentrated largely on the early response of alveolar macrophage and the later fibroblastic stimulation. But the role of the other cells and continuing cell injury in the pathogenesis has not been fully studied. And the chemical factors such as prostaglandin, fibroblast stimulating factor and inhibiting factor and chemotaxin are also participated in the mechanism of pulmonary fibrosis in silicosis. In order to clarify the role of alveolar cells and prostaglandin, we investigated the changes of the cellularities in bronchoalveolar lavage fluid and tissue pathology in the experimental silicosis with the time sequence. The experimental animals were divided into 3 groups; control group received only intratracheal injection of 0.5 ml saline, silica group received the intratracheal instillation of 40 mg silica with the same amount saline, and aspirin group received 450 mg/kg of aspirin after silica instillation. The results were as follows: 1) The total cells of bronchoalveolar lavage fluid in the silica group markedly increased in comparison with the control group, but there was no significant difference between the silica and aspirin groups. 2) The percentages of alveolar macrophages to the total number of cells in the silica group tended to be lower than those in the control group and also lower than those in the aspirin group at the 1st week after silica instillation. 3) The percentages of neutrophils to the total number of cells in the silica group were significantly higher than those in the control group during the entire period and also higher than those in the aspirin group at the 3rd day after silica instillation. 4) In the silica group, the percentages of lymphocytes to the total number of cells were increased 143 progressively with the time course and those were significantly higher than those in the control group from the 3rd week after silica administration. There were marked differences of lymphocyte percentages between the silica and aspirin groups at the 1st week after silica instillation. 5) The inflammatory change was observed in the rat lung at the 1st day after silica instillation. Also the silicotic nodule appeared in the silica group at the 1st week but we could not find out that nodule in the aspirin group at that time. The fibrotic changes in the rat lung tended to be increased progressively with the time course, therefore, the diffuse fibrotic pattern appeared in the whole field at the 20th week after silica instillation. 6) By the electron microscopy, there were gradual increases of phagosomes and vacuoles in the alveolar macrophage in the silica group as compared with the control group. These results suggest that the neutrophils and the lymphocytes have also participated in the pulmonary fibrosis even though the alveolar macrophage has a major role, and prostaglandin mediate the inflammation and pulmanary fibrosis in the experimental silicosis.

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Human Norovirus Replication in Temperature-Optimized MDCK Cells by Forkhead Box O1 Inhibition

  • Jeong, Eun-Hye;Cho, Se-Young;Vaidya, Bipin;Ha, Sang Hoon;Jun, Sangmi;Ro, Hyun-Joo;Lee, Yujeong;Lee, Juhye;Kwon, Joseph;Kim, Duwoon
    • Journal of Microbiology and Biotechnology
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    • v.30 no.9
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    • pp.1412-1419
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    • 2020
  • Human noroviruses (HuNoVs) are a leading cause of gastroenteritis outbreaks worldwide. However, the paucity of appropriate cell culture models for HuNoV replication has prevented developing effective anti-HuNoV therapies. In this study, first, the replication of the virus at various temperatures in different cells was compared, which showed that lowering the culture temperature from 37℃ significantly increased virus replication in Madin-Darby canine kidney (MDCK) cells. Second, the expression levels of autophagy-, immune-, and apoptosis-related genes at 30℃ and 37℃ were compared to explore factors affecting HuNoV replication. HuNoV cultured at 37℃ showed significantly increased autophagy-related genes (ATG5 and ATG7) and immune-related genes (IFNA, IFNB, ISG15, and NFKB) compared to mock. However, the virus cultured at 30℃ showed significantly decreased expression of autophagy-related genes (ATG5 and ATG7), but not significantly different major immune-related genes (IFNA, ISG15, and NFKB) compared to mock. Importantly, expression of the transcription factor FOXO1, which controls autophagy- and immune-related gene expression, was significantly lower at 30℃. Moreover, FOXO1 inhibition in temperature-optimized MDCK cells enhanced HuNoV replication, highlighting FOXO1 inhibition as an approach for successful virus replication. In the temperature-optimized cells, various HuNoV genotypes were successfully replicated, with GI.8 showing the highest replication levels followed by GII.1, GII.3, and GII.4. Furthermore, ultrastructural analysis of the infected cells revealed functional HuNoV replication at low temperature, with increased cellular apoptosis and decreased autophagic vacuoles. In conclusion, temperature-optimized MDCK cells can be used as a convenient culture model for HuNoV replication by inhibiting FOXO1 and providing adaptability to different genotypes.

Effects of cyclopiazonic acid and aflatoxin B1 on arachidonic acid metabolism, calcium mobilization and ultrastructure in rabbit platelet aggregation (Cyclopiazonic acid 및 aflatoxin B1이 토끼의 혈소판에서 arachidonic acid 대사, 칼슘 동원 및 초미세구조에 미치는 영향)

  • Hong, Choong-man;Jang, Dong-deuk;Cho, Myung-haing
    • Korean Journal of Veterinary Research
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    • v.36 no.4
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    • pp.873-886
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    • 1996
  • For better understanding the interrelationship of hemorrhage and aggregation mechanism, cyclopiazonic acid(CPA) known as promoting the aggregation of platelet, aflatoxin $B_1(AFB_1)$ inhibiting platelet aggregation were used as toxic mycotoxins in these studies. In order to investigate the potential role of prostaglandin metabolism on the platelet aggregation, a variety of prostaglandin metabolites such as $PGF_{2{\alpha}}$, $PGE_2$ and $TXB_2$ were measured in homogenized rabbit platelets by TLC and LSC. And the role of $Ca^{{+}{+}}$ on the platelet aggregation was investigated by flow cytometer. Finally, the morphological effects of mycotoxins on platelet were determined by transmission electron microscope. The results and conclusions obtained from these studies are: 1) CPA induced no changes but $AFB_1$ increased $PGE_2$ and $TXB_2$. 2) CPA promoted ADP, collagen, thrombin, A.A., and PAF-induced $Ca^{{+}{+}}$ release. $AFB_1$, however, decreased $Ca^{{+}{+}}$ level except collagen-induced $Ca^{{+}{+}}$ release. When the calcium blocker, verapamil, was used, CPA decreased thrombin-induced $Ca^{{+}{+}}$ release and increased collagen, ADP, PAF and A.A.-induced $Ca^{{+}{+}}$ release. $AFB_1$ in contrast decreased the all factors induced $Ca^{{+}{+}}$ release. 3) $AFB_1$ did not induce any ultrastructural changes except large vacuole formation in a few platelets. And CPA also did not induce any changes except moderate shape change, indicator of platelet activation. In conclusion, CPA promoted platelet aggregation by the increases of $Ca^{{+}{+}}$ release but had no changes in A.A. metabolites. Antiaggregating effects of $AFB_1$ may be due to decreases of $Ca^{{+}{+}}$ release and increases of $PGE_2$ and $PGF_{2{\alpha}}$ formation. These data provide the basis for the future study of mobilization and function of $Ca^{{+}{+}}$ in platelet aggregation.

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The Relationship between Water-Bloom and Distribution of Microorganisms That Inhibit the Growth of Cyanobacterium (Anabaena cylindrica) (수화와 시안세균(Anabaena cylindrica) 생장 억제 미생물 분포도의 상관관계)

  • Kim, Chul-Ho;Lee, Jung-Ho;Choi, Yong-Keel
    • Korean Journal of Microbiology
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    • v.34 no.4
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    • pp.188-193
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    • 1998
  • The authors examined the variations of environmental factors, the distributions of cyanobacteria, heterotrophic bacteria, and microorganisms that inhibit the growth of Anabaena cylindrica according to development and extinction of cyanobacterial bloom at a site in Daechung Dam reservoir. And certified the relationship between each other. Water temperature variated in a typical pattern. pH and concentrations of dissolved oxygen and chlorophylla was high in bloom period, and lowered with the decline of bloom. Phosphorus played as a growth-limiting factor at this study site. Total nitrogen concentration increased during blooming period, which indicated that nitrogen has been fixed by aquatic organisms such as cyanobacteria. Cyanobacteria distributed from June 17, and such cyanobacterial species as Anabaena spp., Aphanizomenon spp., Microcystis spp., Oscillatoria spp. and Phormidium spp. was detected during study period. Anabaena spp. distributed relatively highly distributed from July 23 to September 22, and disappeared completely at September 29. Heterotrophic bacterial and cyanobacterial populations varied inverse-proportionally. There was a relevancy between the variations of Anabaena spp., heterotrophic bacteria, and microorganisms that inhibit the growth of Anabaena cylindrica. Microorganisms that inhibit the growth of Anabaena cylindrica distributed from early growth phase of Anabaena spp. population to immediately after the extinction of Anabaena spp. With the population of Anabaena cylindrica growth-inhibiting microorganisms decreasing, increases of heterotrophic bacterial population followed it. Thease results indicate that microorganisms have a part in the extinction of cyanobacterial bloom, especially at its destroying period.

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Several Factors on Bulblets Regeneration from Callus Culture in Lilium longiflorum 'Celia' (백합 'Gelia' 캘러스로부터 자구 재분화에 미치는 제요인)

  • 박소영;김시동;신세균;이철희;백기엽
    • Korean Journal of Plant Tissue Culture
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    • v.24 no.3
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    • pp.183-188
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    • 1997
  • Callus from scale segments of Lilium longiflorum 'Gelia' was effectively induced and maintained from unorganized tissue on the semi-solid medium by 0.42% Bacto agar with MS basal salts and vitamins of SH medium supplemented with 0.5 mg/L 2, 4-D, 1.0 mg/L NAA, 0.3 mg/L BA, and 3% sucrose. More than 5% of high sucrose level had inhibiting effect on regeneration capacity of formed callus and decreased callus growth. Various combinations of nitrogen did not effective to proliferate the ELC (Embryogenic-like callus), but friability of callus was increased in the medium containing only nitrate as nitrogen source. 5 mL conditioned medium into 30 mL fresh medium was good for cell growth. However friable cell aggregates during suspension culture had to form hard callus which hindered to establish suspention culture system. Addition of 2 g/L casein hydrolysate increased callus growth and friability of the hard callus. As a result of anatomical observation of callus, organogenesis such as shoots, roots and bulblets was independently induced from callus tissue. Somatic embryogenesis from callus tissue could be observed with low frequency.

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