• Title/Summary/Keyword: Stimulated absorption

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Antiallergic and Anti-inflammatory Effects of Perilla frutescens var. acuta (자소엽의 항알레르기와 항염증효과)

  • You, Jin-Su;Kim, Sang-Yong;Kim, Sang-Hyun;Shin, Tae-Yong
    • Korean Journal of Pharmacognosy
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    • v.43 no.2
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    • pp.163-166
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    • 2012
  • In the present study, we investigated the effect of the water extract of Perilla frutescens var. acuta (Labiatae; WEPF) on the mast cell-mediated allergic reactions. WEPF was anally administered to mice for high and fast absorption. WEPF inhibited compound 48/80-induced systemic allergic reaction. WEPF attenuated immunoglobulin E (IgE)-mediated local allergic reaction. In addition, WEPF decreased the gene expression of pro-inflammatory cytokines in phorbol 12-myristate 13-acetate plus calcium ionophore A23187 (PMACI)-stimulated HMC-1 cells. These results indicate that WEPF inhibits mast cell-mediated allergic reactions in vivo and in vitro.

Influence of temperature of a second harmonic crystal on the power stability of intracavity frequency-doubled diode pumped Nd:$YVO_4$ lasers (비선형 광학 결정의 온도가 다이오드 레이저 펌핑된 내부 공진기형 Nd:$YVO_4$ 이차 조화파 레이저의 출력 안정도에 미치는 영향)

  • Kim Ji Won;Yun Chun Seop
    • Proceedings of the Optical Society of Korea Conference
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    • 2003.02a
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    • pp.220-221
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    • 2003
  • Intracavity second harmonic generation of diode pumped solid state lasers in the visible and ultraviolet regions provide efficient, compact and robust light sources for various applications, such as optical data storage, material processing, spectroscopy and bioanalysis. Advantages of neodymium vanadate (Nd:$YVO_4$) as a gain medium for intracavity-doubled lasers over Nd:YAG lie in the facts that the gain spectrum consists of a single line with short absorption depth, and that the stimulated emission cross sections are larger. (omitted)

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Technical study on quantitative analysis of the toxic gas concerning the combustion property of interior materials of railway car (철도차량용 내장 재료의 연소특성을 고려한 유해가스 정량분석 기법연구)

  • Park, Ji-Young;Lee, Cheul-Kyu;Lee, Duck-Hee;Jung, Woo-Sung;Chung, Hoe-Il
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.1114-1118
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    • 2008
  • In previous fire accident of railway car, the fatality was relatively high by toxic gas poisoning cause of closed space. So the necessity of quantifying toxic gas in combustion gas was recognized and then, FT-IR spectroscopy was introduced for real-time analysis of mixed gases and stimulated analysis of the concentration of several gases. Thus, in this study, absorption bands using FT-IR were obtained by each component of combustion gases for interior materials of railway car such as flooring materials and moquette seat. And then the sample spectra were compared with the spectra of NO, $NO_2$, $SO_2$ reference gases, we could obtain some identical peaks of them.

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Effects of Carnosine and Related Compounds on Monosaccharide Autoxidation and $H_2O_2$ Formation

  • Lee, Beom-Jun;Kang, Kyung-Sun;Nam, Sang-Yoon;Park, Jae-Hak;Lee, Yong-Soon;Yun, Young-Won;Cho, Myung-Haing
    • The Korean Journal of Physiology and Pharmacology
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    • v.3 no.3
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    • pp.251-261
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    • 1999
  • The effects of carnosine and related compounds (CRCs) including anserine, homocarnosine, histidine, and ${\beta}-alanine$ on monosaccharide autoxidation and $H_2O_2$ formation were investigated. The incubation of CRCs with D-glucose, D-glucosamine, and D, L-glyceraldehyde at $37^{\circ}C$ increased the absorption maxima at 285 nm, 273 nm, and $290{\sim}330$ nm, respectively. D, L-glyceraldehyde was the most reactive sugar with CRCs. The presence of copper strongly stimulated the reaction of carnosine and anserine with D-glucose or D-glucosamine. Carnosine and anserine stimulated $H_2O_2$ formation from D-glucose autoxidation in a dose-dependent manner in the presence of 10 ${\mu}M$ Cu (II). The presence of human serum albumin (HSA) decreased their effect on $H_2O_2$ formation. Carnosine and anserine has a biphasic effect on ${\alpha}-ketoaldehyde$ formation from glucose autoxidation. CRCs inhibited glycation of HSA as determined by hydroxymethyl furfural, lysine residue with free ${\varepsilon}-amino$ group, and fructosamine assay. These results suggest that CRCs may be protective against diabetic complications by reacting with sugars and protecting glycation of protein.

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The Effect of Ginseng Saponin Fraction on Antioxidant Activity of $\alpha$-Tocopherol ($\alpha$-tocopherol의 항산화작용에 미치는 인삼사포닌분획의 영향)

  • 주충노;곽한식
    • Journal of Ginseng Research
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    • v.12 no.2
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    • pp.128-134
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    • 1988
  • The effect of the saponin fraction extracted from Panax ginseng C.A. Meyer on the antioxidant activity of $\alpha$-tocopherol was investigated in vitro as well as in vivo. Microsomal preparation of rat(Winter, 180-200g) liver was incubated in the mixture containing NADPH, $Fe^{3+}$, ATP, $\alpha$-tocopherol with and/or without ginseng saponin fraction for 30 minutes and the malondialdehyde formed was assayed and found that the saponin fraction stimulated the antioxidant activity of $\alpha$-tocopherol cooperatively. It was also realized that the cooperative stimulation of the antioxidant activity of $\alpha$-tocopherol was most eminent when the concentration of the saponin fraction was around $10^{-5}$% in the reaction mixture. Alcoholic suspension of $\alpha$-tocopherol with and f or without ginseng saponin fraction was administered orally to rats in which the lipid preoccupation was induced by ethanol administration and the lipid peroxide contents of the liver were assayed at certain periods of time after $\alpha$-tocopherol administration in this animal. From the previous work and present experimental results, it seemed that the saponin fraction accelerated the absorption of $\alpha$-tocopherol and therefore stimulated the antioxidant activity of $\alpha$-tocopherol more effectively in the animal body.

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Effect of Eriobotrya japonica Leaf and Seed Extracts on Adipogenesis (비파잎과 씨 추출물의 지방생성 억제효과)

  • Min, Oh-Jin;Oh, Jin;Kim, Hyeon-A;Kim, Min-Sook;Baek, Hum-Young;Kim, Yong-Jae;Rhyu, Dong-Young
    • Korean Journal of Pharmacognosy
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    • v.41 no.4
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    • pp.270-274
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    • 2010
  • Obesity is caused from an imbalance between energy intake and expenditure, which may lead to pathologic growth of adipocytes and accumulation of fat in tissue. We examined the inhibitory effects of Eriobotrya japonica leaf and seed extracts on lipid absorption in vitro and fat accumulation during the differentiation of 3T3-L1 to adipocytes. 3T3-L1 preadipocytes were stimulated with DMEM media containing 10% FBS, 0.5 mM 3-isobuthyl-1-methyxanthine (IBMX), $5\;{\mu}g/ml$ insulin, and $1\;{\mu}g/ml$ dexamethasone for differentiation to adipocytes. E. japonica leaf extract at concentration of 0.5 or 1 mg/ml inhibited pancreatic lipase activity. The cell viability of 3T3-L1 adipocytes slightly reduced about 3% by treatment of E. Japonica leaf and seed extracts. The leaf and seed extracts of E. japonica effectively inhibited the accumulations of lipid droplet and expression of $C/EBP{\alpha}$ promoting adipogenesis. Thus, this data suggest that E. japonica leaf and seed extracts inhibit fat accumulation through regulation of $C/EBP{\alpha}$, and leaf extract is more effective in lipid absorption and adipogenesis than seed extract.

Optical dating of Quaternary sediment (광 여기 루미네센스를 이용한 신기 퇴적층의 연대측정)

  • 홍덕균;최정헌;한정희;최만식;정창식
    • The Journal of the Petrological Society of Korea
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    • v.10 no.3
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    • pp.202-211
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    • 2001
  • Luminescence is a physical phenomenon exhibited by many non-conducting, crystalline materials, such as quartz and feldspar. Within the crystals, energy absorbed from ionising radiation frees electrons to move through the crystal lattice and some are trapped at defects in the lattice. Observable luminescence is produced by electrons, released from traps by stimulation by absorption of light, which recombine with lattice defects which act as luminescence centers - optically stimulated luminescence (OSL). In a similar way to thermoluminescence(TL) dating, controlled measurement of the OSL signal can provide a means of determining the time since the last exposure of a layer of sediment to sunlight, the age of the sediment. However, whereas in the thermoluminescence dating of sediment only part of the latent thermoluminescence signal is bleached by sunlight as the sediment is deposited and allowance must be made during the laboratory measurements for the light insensitive component, optically induced luminescence dating has the advantage of working only with light sensitive traps in the crystal. Determination of the time since deposition of Quaternary sediment samples from the OSL of quartz grains using blue light was performed. A series of experiments and recent developments relating OSL dating are described, beginning by identifying the features which make OSL signals suitable for the development of dating method. Additionally, there are suggestions as to future research for obtaining reliable ages and a comment on current best practice on procedures, with the dating results of Quaternary sediment.

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Suppression of PMA-induced Differentiation via Foam Cell Formation in THP-1 Cells by 7-Ketocholesterol (THP-1 세포에서 거품세포 형성과 단핵구 분화 및 활성화에서 7-ketocholesterol의 역할)

  • Lee, Mi Sun;Park, Si Eun;Kim, Koanhoi;Park, Young Chul
    • Journal of Life Science
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    • v.32 no.2
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    • pp.142-147
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    • 2022
  • Oxysterols are known to be involved in the physiopathology of atherosclerosis. Since 7-ketocholesterol (7-KC) is found in large amounts in oxysterols and in atherosclerotic plaque, the study on how 7-KC may affect monocyte differentiation induced by phorbol myristate acetate (PMA) in the monocytic cell line, THP-1, is essential. 7-KC induced a dose-dependent reduction in cell proliferation without inducing cytotoxicity, and the substantial staining of Nile red demonstrates the increased absorption of intracellular lipids. Although 7-KC itself did not increase cell adhesion, it markedly decreased the adhesion of cells treated with PMA. Furthermore, by observing the effect of 7-KC on phagocytosis using fluorescent-labeled latex beads, 7-KC's ability to abolish phagocytosis in PMA-stimulated macrophages was illustrated. The effect of 7-KC on the expression of selected protein markers on the process of differentiation induced by PMA in THP-1 cells was also examined. 7-KC inhibited expression of ICAM-1, CD11a, SR-A1, and SR-B2 (CD36) in PMA-stimulated THP-1 cells. Conversely, 7-KC drastically increased the expression of SR-D1 (CD68)in PMA-stimulated THP-1 cells. In conclusion, these results suggest that 7-KC modulates monocyte differentiation and activation via the intracellular accumulation of lipid droplets.

Principles of Physiology of Lipid Digestion

  • Bauer, E.;Jakob, S.;Mosenthin, R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.2
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    • pp.282-295
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    • 2005
  • The processing of dietary lipids can be distinguished in several sequential steps, including their emulsification, hydrolysis and micellization, before they are absorbed by the enterocytes. Emulsification of lipids starts in the stomach and is mediated by physical forces and favoured by the partial lipolysis of the dietary lipids due to the activity of gastric lipase. The process of lipid digestion continues in the duodenum where pancreatic triacylglycerol lipase (PTL) releases 50 to 70% of dietary fatty acids. Bile salts at low concentrations stimulate PTL activity, but higher concentrations inhibit PTL activity. Pancreatic triacylglycerol lipase activity is regulated by colipase, that interacts with bile salts and PTL and can release bile salt mediated PTL inhibition. Without colipase, PTL is unable to hydrolyse fatty acids from dietary triacylglycerols, resulting in fat malabsorption with severe consequences on bioavailability of dietary lipids and fat-soluble vitamins. Furthermore, carboxyl ester lipase, a pancreatic enzyme that is bile salt-stimulated and displays wide substrate reactivities, is involved in lipid digestion. The products of lipolysis are removed from the water-oil interface by incorporation into mixed micelles that are formed spontaneously by the interaction of bile salts. Monoacylglycerols and phospholipids enhance the ability of bile salts to form mixed micelles. Formation of mixed micelles is necessary to move the non-polar lipids across the unstirred water layer adjacent to the mucosal cells, thereby facilitating absorption.

The Role of Milk Products in Metabolic Health and Weight Management

  • Zemel, Michael B.
    • Journal of Dairy Science and Biotechnology
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    • v.28 no.1
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    • pp.17-28
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    • 2010
  • A substantial body of evidence has emerged over the last decade in support of the novel concept that dietary calcium and dairy foods play an important role in regulating energy metabolism and thereby promote healthy weight management and reduce obesity risk. This concept has been demonstrated in experimental animals studies, cross-sectional and prospective population studies and a number of randomized clinical trials. Notably, the effects of dairy foods in weight management are more consistent than the effects of supplemental calcium across clinical trials, and calcium per se is responsible for approximately 40-50% of the effects of dairy. The calcium component is only effective in individuals with chronically low calcium intake, as it serves to prevent the endocrine response to low calcium diets which otherwise favors adipocyte energy storage; calcium also serves to promote energy loss via formation of calcium soaps in the gastrointestinal tract and thereby reduce fat absorption. The calcium-independent anti-obesity bioactivity of dairy resides primarily in whey. The key components identified to date are leucine and bioactive peptides resulting from whey protein digestion. The high concentration of leucine in whey stimulates a repartitioning of dietary energy from adipose tissue to skeletal muscle where it provides the energy required for leucine-stimulated protein synthesis, resulting in increased loss of adipose tissue and preservation of skeletal muscle mass during weight loss. Finally, dairy rich diets suppress the oxidative and inflammatory responses to obesity and thereby attenuate the diabetes and cardiovascular disease risk associated with obesity.

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