• 제목/요약/키워드: GLE

검색결과 34건 처리시간 0.024초

Relationship of ground level enhancements with solar erupted factors

  • ;조경석
    • 천문학회보
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    • 제35권1호
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    • pp.34.2-34.2
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    • 2010
  • Cosmic rays registered by Neutron Monitors on the surface of the Earth are believed to be coming from outer space, and sometimes also from the exotic objects of the Sun. Ground level enhancement (GLE) is the sudden, sharp and short-lived increase in cosmic rays originated from the Sun. Since GLE is the signature in solar cosmic ray intensity, different solar factors erupted from the Sun can be responsible for causing it. In this context, an attempt has been made to determine quantitative relationships of GLEs > 5% with simultaneous solar, interplanetary and geophysical factors from 1997 through 2006 thereby searching the perpetrators which seem to be causing them. The study has revealed that solar flares are stronger ($0.71{\times}10-4$ w/m2) during GLE peaks than the solar flares ($1.10{\times}10-5$ w/m2) during GLE non-peaks and backgrounds. On the average, the solar wind plasma velocity and interplanetary magnetic field are found stronger during the GLE peaks than the GLE non-peaks and backgrounds indicating that the solar flares, in conjunction with interplanetary shocks, sometimes may cause GLE peaks. Direct proportionality of GLE peaks to simultaneous solar energetic particle (SEP) fluxes imply that the GLE peaks may often be caused by SEP fluxes. Although the high intensity of SEP fluxes are also seen extended few minutes even after GLE peaks, the mean (373.62 MeV) of the GLE associated SEP fluxes is much stronger than the mean (10.35 MeV) of the non-GLE associated SEP fluxes. Evidences are also supported by corresponding SEP fluences that the the mean fluence (${\sim}5.32{\times}107/cm2$) across GLE event was more intense than the mean fluence (${\sim}2.53{\times}106/cm2$) of SEP fluxes across non-GLE event.

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Graviola (Annona muricata) 잎 추출물의 항산화 및 미백 효과 (Antioxidant and Skin Whitening Effect of Graviola (Annona muricata) Leaf Extracts)

  • 조은희;김인혜;이재화
    • 공업화학
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    • 제28권2호
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    • pp.198-205
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    • 2017
  • 본 연구에서는 Annona muricata 잎 추출물(graviola leaf extracts, GLE)의 항산화(antioxidant), 항균(antibacterial), 미백(whitening) 및 주름 개선(anti-wrinkle) 효과 등을 조사하였으며, 항산화(antioxidant) 효과에 대한 활성은 전자공여능 분석을 통해 측정하였다. 그 결과 GLE는 농도 의존적으로 전자공여능이 증가하는 것으로 나타났다. GLE의 항균 활성은 paper disc법으로 측정하여 나타냈으며, 표준물질인 ampicillin과 비교하여 메티실린내성 황색포도상구균 CCARM3115에서 비교적 높은 항균 활성을 나타내었다. GLE에 대한 미백(whitening) 효과 역시 tyrosinase 저해 활성 측정을 통해 진행하였으며, 그 결과 GLE는 농도가 증가함에 따라 tyrosinase 활성이 감소하는 것으로 나타났다. GLE 농도에 따른 L-tyrosine을 DOPA로 바꾸는 데 관여하는 hydroxylation 반응과 관련한 mushroom tyrosinase의 저해 활성은 표준물질인 arbutin에 비해 $125{\sim}250{\mu}g/mL$ 농도 범위에서 특히 높게 나타났다. B16-F10 cell에 대한 melanin 생합성 저해능은 농도 의존적으로 감소하는 경향을 보였으며, $100{\mu}g/mL$에서 76.7%를 나타났다. 주름 생성과 관련하여서는 elastase 저해 활성 측정을 통해 진행하였으며, 그 결과 동일한 농도에서 GLE 및 ursolic acid는 10.5, 56.5%로 나타났다. 이러한 결과를 통해 Annona muricata 잎 추출물(Graviola Leaf Extracts, GLE)이 항산화 및 미백 활성에 상당한 효과가 있음을 확인할 수 있었으며, 미백 화장품 성분으로서 과색소침착 치료에 유용할 것으로 기대된다.

영지(靈芝) 추출물이 Rat fetus 두개골로부터 분리한 조골세포에 미치는 영향 (The Effects of Ganoderma lucidum Extract on Osteoblast in Rat Fetus Calvarial Cells)

  • 정은혜;유동열
    • 대한한방부인과학회지
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    • 제27권2호
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    • pp.23-33
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    • 2014
  • Objectives: In this study, the author aimed to evaluate the effect of EtOH extract of Ganoderma lucidum (GLE) on osteoblast proliferation in rat fetus calvarial cells. Methods: The osteoblast separated from rat fetus calvariae was cultivated for 6~21 days and evaluated the cell function. After the addition of GLE on the culture medium, we determined the effect of GLE on the cell viability, cell proliferation, bone matrix protein synthesis, alkaline phosphatase (ALP) activity, collagen synthesis and calcified nodule formation of the cultivated osteoblast. Results: GLE did not change the survival rate of rat calvarial osteoblast. GLE increased the proliferation of rat calvarial osteoblast. GLE increased ALP activity of rat calvarial osteoblast. GLE increased bone matrix protein synthesis of rat calvarial osteoblast. GLE increased collagen synthesis of rat calvarial osteoblast. GLE slightly affected calcified nodule formation of rat calvarial osteoblast. Conclusions: This study suggests that Ganoderma lucidum might improve the osteoporosis resulted from augmentation of osteoblast proliferation.

DNA손상 및 돌연변이에 대한 명지버섯의 방어효능 (The Protective Effects of Ganoderma lucidum on the DNA Damage and Mutagenesis)

  • 이길수;공석경;최수영
    • Biomolecules & Therapeutics
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    • 제11권2호
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    • pp.139-144
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    • 2003
  • Ganoderma lucidum is commonly known as medically potent mushroom, which has been widely used in China and other oriental countries for the treatment of various diseases, including cancer. In this report, we investigated the anti-oxidant and protective effect of Ganodema lucidum extract (GLE) against the DNA damage induced by free radical and U.V. In the assay of cell growth inhibition, the inhibitory cell growth rate induced by hydroxyl radical was dose-dependently decreased by GLE. This results support that GLE has a detoxifying activity against cytotoxicity of hydroxyl radical in E. coli cell. GLE also protected ColE1 plasmid DNA damage in the concentration of 200$\mu\textrm{g}$ per reaction on the DNA fragmentation assay. The nuclear tailing by hydrogen peroxide in single cell gel electrophoresis(SCGE) was decreased by GLE in the concentration of 50$\mu\textrm{g}$/ml. These data indicate that Ganoderma lucidum has an anti-oxidative activity to hydrogen peroxide. The mutation rate after irradiation of U.V. was reduced by 50$\mu\textrm{g}$/ml GLE and total number of Rif (Rifampicin) resistant mutants was decreased in a concentration dependent manner when added the GLE exogenously in a culture media. According to the results, it is likely that GLE has not only an anti-oxidative activity to hydroxyl radical but also an anti-mutagenic activity to U.V. mutagenesis.

Effects of Psidium guajava Leaf Extract on Apoptosis Induction Through Mitochondrial Dysfunction in HepG2 Cells

  • Nguyen, Van-Tinh;Ko, Seok-Chun;Oh, Gun-Woo;Heo, Seong-Yeong;Jung, Won-Kyo
    • 한국미생물·생명공학회지
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    • 제47권1호
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    • pp.43-53
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    • 2019
  • The anticancer activity of guava (Psidium guajava L.) leaf extract (GLE) occurs via the induction of apoptosis in cancer cells. However, the mechanism behind GLE-induced apoptosis in the human hepatocellular carcinoma cell line HepG2 remains unclear. In the present study, we investigated the apoptotic effects and mechanism of action of GLE in cultured HepG2 cells. The results showed that GLE induced reactive oxygen species (ROS) synthesis and disrupted the mitochondrial membrane potential (${\Delta}{\Psi}m$). Moreover, GLE increased the expression of apoptotic pathway proteins, such as the cleaved forms of caspase-3, -8, and -9; the translocation of Bax and cytochrome c (cyt-c) from the mitochondria to the cytosol; and the downregulation of Bcl-2. In addition, p53 protein expression was increased upon GLE treatment. These observations indicate that the GLE-induced apoptosis in HepG2 cells is mediated by mitochondrial ROS generation, followed by caspase activation and cyt-c release, suggesting that GLE may be a promising candidate for the development of novel drugs for the treatment of liver cancers.

인간 비만세포에서 그라비올라 잎 추출물의 항알러지 효과 (Anti-allergic Effect of Graviola Leaf Extract in Human Mast Cells)

  • 김대용
    • 한국응용과학기술학회지
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    • 제37권6호
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    • pp.1764-1772
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    • 2020
  • 본 연구는 그라비올라(Annona muricata)가 인간 비만세포(LUVA 세포)에서 immunoglobulin(Ig) E-매개 알러지 반응에 어떠한 효과를 나타내는지 확인하는데 목적이 있다. 그라비올라 잎 추출물(GLE)의 항알러지 효과를 알아보기 위해 IgE로 감작된 비만세포에 다양한 농도의 추출물을 처리하였다. 비만세포의 IgE-매개 탈과립 실험 결과, GLE가 LUVA 세포에서 histamine, β-hexosaminidase, TNF-α, IL-4 및 IL-6의 방출을 유의하게 억제하였다. 또한 GLE는 IgE 유도에 의한 Lyn과 Syk의 인산화를 억제하였고 그 하위 경로에 있는 MAPK의 활성을 억제하였다. 이상의 결과는 GLE가 비만세포 활성화 및 알러지 반응을 억제할 수 있음을 보여주고, 이는 GLE가 항알러지 효과를 통하여 기능성 화장품 소재로서의 활용이 가능함을 시사한다.

Ginseng Leaf Extract Prevents High Fat Diet-Induced Hyperglycemia and Hyperlipidemia through AMPK Activation

  • Yuan, Hai-Dan;Kim, Sung-Jip;Quan, Hai-Yan;Huang, Bo;Chung, Sung-Hyun
    • Journal of Ginseng Research
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    • 제34권4호
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    • pp.369-375
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    • 2010
  • This study evaluated the protective effects of ginseng leaf extract (GLE) against high fat-diet-induced hyperglycemia and hyperlipidemia, and explored the potential mechanism underlying these effects in C57BL/6J mice. The mice were randomly divided into four groups: normal control, high fat diet control (HFD), GLE-treated at 250 mg/kg, and GLE-treated at 500 mg/kg. To induce hyperglycemic and hyperlipidemic states, mice were fed a high fat diet for 6 weeks and then administered GLE once daily for 8 weeks. At the end of the treatment, we examined the effects of GLE on plasma glucose, lipid levels, and the expression of genes related to lipogenesis, lipolysis, and gluconeogenesis. Both GLE groups lowered levels of plasma glucose, insulin, triglycerides, total cholesterol, and non-esterified fatty acids when compared to those in HFD group. Histological analysis revealed significantly fewer lipid droplets in the livers of GLE-treated mice compared with HFD mice. To elucidate the mechanism, Western blots and RT-PCR were performed using liver tissue. Compared with HFD mice, GLE-treated mice showed higher levels of phosphorylation of AMP-activated protein kinase (AMPK) and its substrate, acetyl-CoA carboxylase, but no differences in the expression of lipogenic genes such as sterol regulatory element-binding protein 1a, fatty acid synthase, sterol-CoA desaturase 1 and glycerol-3-phosphate acyltransferase. However, the expression levels of lipolysis and fatty acid uptake genes such as peroxisome proliferator-activated receptor-$\alpha$ and CD36 were increased. In addition, phosphoenolpyruvate carboxykinase gene expression was decreased. These results suggest that GLE ameliorates hyperglycemia and hyperlipidemia by inhibiting gluconeogenesis and stimulating lipolysis, respectively, via AMPK activation.

Immune-Enhancing Effects of Green Lettuce (Lactuca sativa L.) Extracts through the TLR4-MAPK/NF-κB Signaling Pathways in RAW264.7 Macrophage Cells

  • Seo, Hyun-Ju;Jeong, Jin Boo
    • 한국자원식물학회지
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    • 제33권3호
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    • pp.183-193
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    • 2020
  • Recently, as a natural substance has been emphasized interest in research to enhance the immune function. Green lettuce (Lactuca sativa L.) is a popular vegetable used fresh and it contains various phytochemicals and antioxidant compounds, and has been reported to have various physiological activities such as antibacterial, antioxidant, antitumor and anti-mutagenic. However, only a few studies have investigated on the mechanism of action of immune-enhancing activity of lettuce. Therefore, in this study, the immunomodulatory activities and potential mechanism of action of Green lettuce extracts (GLE) were evaluated in the murine macrophage cell line RAW264.7. GLE significantly increased NO levels by RAW264.7 cells, as well as expressions of immunomodulators such as iNOS, COX-2, IL-1β, IL-6, IL-12, TNF-α and MCP-1. Although GLE activated ERK1/2, p38, JNK and NF-κB, GLE-mediated expressions of immunomodulators was dependent on p38, JNK and NF-κB. In addition, TLR4 inhibition blocked GLE-mediated expressions of immunomodulators and activation of p38, JNK and NF-κB. Taken together, these results demonstrated that TLR4-MAPK/NF-κB signalling pathways participated in GLE-induced macrophage activation and GLE could be developed as a potential immunomodulating functional food.

C57BL/6N 마우스 탈모모델에서 미세다륜침과 영지추출물이 모발성장에 미치는 영향 (Effects of Ganoderma Lucidum Extract Ethanol Extract and Microneedle Therapy System on Hair Growth in an Alopecia Model of C57BL/6N Mice)

  • 주봉현;유선애;강경화;이승연
    • 대한한방소아과학회지
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    • 제28권2호
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    • pp.72-87
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    • 2014
  • Objectives This study was carried out to investigate the effect of Ganoderma lucidum extract (GLE) and microneedle therapy system (MTS) on hair growth in an alopecia model of C57BL/6N mice. Methods Five-week old mice were depilated and separated in 4 groups ; CON (50% EtOH), MXD (5% Minoxidil), MTS and GLE + MTS. The treatments were applied twice a week for 3 weeks. The hair growth was determined photographically, the hair density, thickness and length were identified by Folliscope and the weights of body and organs were measured. In dorsal skin tissue, the expression of hair growth-related gene and protein was analyzed by RT - PCR or Western blot. In addition, the hair follicles in the dermis were observed by H&E staining. Results The promotion of hair growth was observed in GLE + MTS and MTS compared to CON. The hair density, thickness and length were also improved in GLE + MTS and MTS compared to CON. The mRNA expression of TGF-${\alpha}$, TGF-${\beta}1$, IGF-1, PRL and PL and the protein expression of VEGF and IGF-1 were increased in GLE + MTS and MTS compared to CON. The hair follicles and hair root growth were improved in GLE + MTS and MTS compared to CON. In the above results, GLE + MTS were more effective than MTS. Conclusions These results suggest that GLE and MTS has a hair growth activity and can be useful for the treatment of alopecia.

Psidium guajava L. leaf extract inhibits adipocyte differentiation and improves insulin sensitivity in 3T3-L1 cells

  • Choi, Esther;Baek, Seoyoung;Baek, Kuanglim;Kim, Hye-Kyeong
    • Nutrition Research and Practice
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    • 제15권5호
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    • pp.568-578
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    • 2021
  • BACKGROUND/OBJECTIVES: Psidium guajava L. (guava) leaves have been shown to exhibit hypoglycemic and antidiabetic effects in rodents. This study investigated the effects of guava leaf extract on adipogenesis, glucose uptake, and lipolysis of adipocytes to examine whether the antidiabetic properties are mediated through direct effects on adipocytes. MATERIALS/METHODS: 3T3-L1 cells were treated with 25, 50, 100 ㎍/mL of methanol extract from guava leaf extract (GLE) or 0.1% dimethyl sulfoxide as a control. Lipid accumulation was evaluated with Oil Red O Staining and AdipoRed assay. Immunoblotting was performed to measure the expression of adipogenic transcription factors, fatty acid synthase (FAS), and AMP-activated protein kinase (AMPK). Glucose uptake under basal or insulin-stimulated condition was measured using a glucose analog 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) amino]-2-deoxy-D-glucose. Lipolysis from fully differentiated adipocytes was measured by free fatty acids release into the culture medium in the presence or absence of epinephrine. RESULTS: Oil Red O staining and AdipoRed assay have shown that GLE treatment reduced lipid accumulation during adipocyte differentiation. Mitotic clonal expansion, an early essential event for adipocyte differentiation, was inhibited by GLE treatment. GLE inhibited the expression of transcription factors involved in adipocyte differentiation, such as peroxisome proliferator-activated receptor 𝛄 (PPAR𝛄), CCAAT/enhancer-binding protein α (C/EBPα), and sterol regulatory element-binding protein-1c (SREBP-1c). FAS expression was also decreased while the phosphorylation of AMPK was increased by GLE treatment. In addition, GLE increased insulin-induced glucose uptake into adipocytes. In lipid-filled mature adipocytes, GLE enhanced epinephrine-induced lipolysis but reduced basal lipolysis dose-dependently. CONCLUSIONS: The results show that GLE inhibits adipogenesis and improves adipocyte function by reducing basal lipolysis and increasing insulin-stimulated glucose uptake in adipocytes, which can be partly associated with antidiabetic effects of guava leaves.