• Title/Summary/Keyword: induced level

Search Result 6,285, Processing Time 0.032 seconds

Electromagnetic Induced Absorption in 5-level Atom using Density Matrix Equation (밀도행렬방정식을 이용한 5-준위 원자에서의 전자기 유도 흡수)

  • 권미랑;문한섭;김경대;박현덕;김중복
    • Proceedings of the Optical Society of Korea Conference
    • /
    • 2000.08a
    • /
    • pp.200-201
    • /
    • 2000
  • 원자와 빛의 결맞음 효과로서 나타나는 많은 흥미로운 현상들 중에서 전자기파 유도 투과(Electro-magnetic Induced Transparency ; EIT)는 원자가 공진주파수를 가진 레이저와 상호작용하였을 때, 광자를 흡수하지 않고 투과하는 현상으로서, 주로 3준위 구도에서 연구되어왔다. 그러나 최근 축퇴된 2준위 구도에서 원자와 빛의 결맞음 효과가 연구되면서 EIT와 정반대의 현상인 전자기 유도 흡수(Electromagnetic Induced Absorption ; EIA)의 관측이 보고되었고 그것과 연관된 물리적 특성들의 연구가 시도되고 있다. (중략)

  • PDF

Inhibition of The Stem Cell Factor-Induced Migration of Mast Cells by Dexamethasone

  • Jeong, Hyun-Ja;Hong, Seung-Heon;Park, Rae-Kil;Kim, Hyung-Min
    • Proceedings of the Korean Society of Applied Pharmacology
    • /
    • 2003.11a
    • /
    • pp.76-76
    • /
    • 2003
  • Mast cells accumulation can be causally related with several allergic inflammations. Previous work has demonstrated that glucocorticoids decreased tissue mast cell number and stem cell factor (SCF)-induced migration of mast cells required p38 mitogen-activated protein kinase (MAPK) activation. In the present study, we investigated the effects of dexamethasone on SCF-induced migration of rat peritoneal mast cells (RPMCs). SCF significantly induced migration of RPMCs at 4 h. Dexamethasone dose-dependently inhibited SCF-induced migration of RPMCs (about 90.1% at 100 nM, P<0.05). MAPK p38 inhibitor, SB203580 (20 ${\mu}$M) also inhibited the SCF-induced migration. The ability of SCF to enhance morphological alteration and F -actin formation was also abolished by treatment of dexamethasone. Dexamethasone inhibited SCF-induced p38 MAPK activation to near basal level and induced the MKP-1 expression. In addition, SCF-induced inflammatory cytokine production was significantly inhibited by treatment of dexamethasone or SB203580 (p<0.01). Our results show that dexamethasone potently regulates SCF -induced migration, p38 MAPK activation and inflammatory cytokine production through expression of MKP-l protein in RPMCs. Such modulation may have functional consequences during dexamethasone treatment, especially mast cell-mediated allergic inflammation disorders.

  • PDF

Lipid lowering activity of Ponciri Fructus and Aurantii Fructus Immaturus on hyperlipemia rats induced by Triton WR-1339. (국산과 중국산 지실(枳實)의 Triton WR-1339 유발 고지혈증(高脂血症) 흰쥐에 대한 효능 연구)

  • Ham, In-hye;Lee, Ung-Cheol;Lee, Byong-hee;Choi, Ho-young
    • The Korea Journal of Herbology
    • /
    • v.22 no.3
    • /
    • pp.109-116
    • /
    • 2007
  • Objective : In order to elucidate hyperlipidemic effects of the fruits of Poncirus trifoliata and Citrus aurantium, our experimental study was performed on hyperlipidemia rats induced by Triton WR-1339. Method : The hyperlipidemia rats induced by intraperitonial injection of triton WR-1339 were treated with the fruits of P. trifoliata (rare and preparata) and C. aurantium 50 and 200mg/kg. The amount of triglyceride. total cholesterol. HDL-cholesterol, LDL-cholesterol, AST. and ALT levels were measured. Results: The levels of triglyceride. total cholesterol and LDL-cholesterol were significantly reduced in fruits of P. trifoliata (rare and preparata) and C. aurantiu. Simvastatine treated group compared with those of control but the level of HDL-cholesterol was incresed. The level of AST and ALT were not significantly reduced by the treatment to the fruits of P. trifoliata (rare and preparata) and C. aurantium. Conclusion : In the hyperlipidemia rats induced by triton WR-1339. the fruits of P. trifoliata (rare and preparata) and C. aurantium showed a hyperlipidemic effect.

  • PDF

Protective Effects of Fermented Soymilk Extract on High Glucose-Induced Oxidative Stress in Human Umbilical Vein Endothelial Cells

  • Yi, Na-Ri;Park, Min-Jung;Han, Ji-Sook
    • Preventive Nutrition and Food Science
    • /
    • v.15 no.1
    • /
    • pp.7-13
    • /
    • 2010
  • We investigated whether the fermented soymilk extract (FSE) has protective effects against high glucose-induced oxidative stress in human umbilical vein endothelial cells (HUVECs). FSE was prepared via fermentation of soymilk with Bacillus subtilis followed by methanol extraction. To determine the protective effect of FSE, oxidative stress was induced by exposing of HUVECs to the high glucose (30 mM) for 48 hr. Exposure of HUVECs to high glucose for 48 hr resulted in a significant (p<0.05) decrease in cell viability, catalase, SOD and GSH-px activity and a significant (p<0.05) increase in intracellular ROS level and thiobarbituric acid reactive substances (TBARS) formation in comparison to the cells treated with 5.5 mM glucose. However, at concentration of 0.1 mg/mL, FSE treatment decreased intracellular ROS level and TBARS formation, and increased cell viability and activities of antioxidant enzymes including catalase, SOD and GSH-px in high glucose pretreated HUVEC. These results suggest that FSE may be able to protect HUVECs from high glucose-induced oxidative stress, partially through the antioxidative defense systems.

Antidiabetic and Antioxidant Effects of Chunggugjang Powder in Streptozotocin-Induced Diabetic Rats (Streptozotocin으로 유발된 당뇨쥐에서 청국장 분말의 항당뇨 및 항산화 효과)

  • Kim Hye-Jong;Kim Young-Chul
    • Environmental Analysis Health and Toxicology
    • /
    • v.21 no.2 s.53
    • /
    • pp.139-146
    • /
    • 2006
  • The purpose of this study was to investigate the effects of dietary chungguajang powder on blood glucose level and hepatic activities of antioxidant enzymes in normal and streptozotocin (STZ)-induced diabetic rats. Sprague-Dawley male ratt ($200{\sim}220g$) of six groups including normal group fed normal diet (N), diabetic group fed normal diet (C), diabetic groups fed chunggugjang powder diet (DC-1%, DC-5%, DC-10%, DC-20%) were used for the experiments. Diabetes was induced by single intraperitoneal injection of streptozotocin as a dose of 70 mg/kg body weight. After 3 weeks the animals were sacrificed and hepatic activities of antioxidant enzymes, serum level of glucose and organ weight were evaluated. Food and water intakes were higher in diabetic groups than normal group. Body weight gain and food efficiency ratio were lower in diabetic groups. However, they were higher in chunggugjang diet groups (DC) than normal diet group (C). The serum glucose levels were significantly lower (p<0.05) in the diabetic groups fed chunggugjang diet (DC-10%, DC-20%) than diabetic group fed normal diet (C). Hepatic activities of superoxide dismutase, catalase, glutathione peroxidase and glutathione S-transferase were lower in diabetic groups than normal group and they were significantly lower in diabetic groups fed chunggugjang diet (DC-20%) compared to diabetic rats fed normal diet (p<0.05). In conclusion, these results indicated that chunggugjang powder would have antidiabetic and antioxidant effects in STZ-induced diabetic rats.

Capsaicin-Induced Apoptosis and Reduced Release of Reactive Oxygen Species in MBT-2 Murine Bladder Tumor Cells

  • Lee, Ji-Seon;Chang, Jong-Sun;Lee, Ji-Youl;Kim, Jung-Ae
    • Archives of Pharmacal Research
    • /
    • v.27 no.11
    • /
    • pp.1147-1153
    • /
    • 2004
  • Bladder cancer is a common cancer with high risk of recurrence and mortality. Intravesicle chemotherapy after trans-urethral resection is required to prevent tumor recurrence and progression. It has been known that antioxidants enhance the antitumor effect of bacillus Calmette-Guerin (BCG), the most effective intravesical bladder cancer treatment. Capsaicin, the major pungent ingredient in genus Capsicum, has recently been tried as an intravesical drug for overactive bladder and it has also been shown to induce apoptotic cell death in many cancer cells. In this study, we investigated the apoptosis-inducing effect and alterations in the cellular redox state of capsaicin in MBT-2 murine bladder tumor cells. Capsaicin induced apoptotic MBT-2 cell death in a time- and dose-dependent manner. The capsaicin-induced apoptosis was blocked by the pretreatment with Z-VAD-fmk, a broad-range caspase inhibitor, or Ac-DEVD-CHO, a caspase-3 inhibitor. In addition to the caspase-3 activation, capsaicin also induced cytochrome c release and decrease in Bcl-2 protein expression with no changes in the level of Bax. Furthermore, capsaicin at the concentration of inducing apoptosis also markedly reduced the level of reactive oxygen species and lipid peroxidation, implying that capsaicin may enhance the antitumor effect of BCG in bladder cancer treatment. These results further suggest that capsaicin may be a valuable intravesical chemotherapeutic agent for bladder cancers.

Attenuation of β-amyloid-induced neuroinflammation by KHG21834 in vivo

  • Kim, Eun-A;Hahn, Hoh-Gyu;Kim, Tae-Ue;Choi, Soo-Young;Cho, Sung-Woo
    • BMB Reports
    • /
    • v.43 no.6
    • /
    • pp.413-418
    • /
    • 2010
  • Beta-Amyloid ($A{\beta}$)-induced neuroinflammation is one of the key events in the development of neurodegenerative disease. We previously reported that KHG21834, a benzothiazole derivative, attenuates $A{\beta}$-induced degeneration of cortical and mesencephalic neurons in vitro. In the present work, we show that KHG21834 reduces $A{\beta}$-mediated neuroinflammation in brain. In vivo intracerebroventricular infusion of KHG21834 leads to decreases in the numbers of activated astrocytes and microglia and level of proinflammatory cytokines such as interleukin-$1{\beta}$ and tumor necrosis factor-$\alpha$ induced by $A{\beta}$ in the hippocampus. This suppression of neuroinflammation is associated with decreased neuron loss, restoration of synaptic dysfunction biomarkers in the hippocampus to control level, and diminished amyloid deposition. These results may suggest the potential therapeutic efficacy of KHG21834 for the treatment of $A{\beta}$-mediated neuroinflammation.

Effect of Molybdenum Induced Copper Deficiency on Peripheral Blood Cells and Bone Marrow in Buffalo Calves

  • Randhawa, C.S.;Randhawa, S.S.;Sood, N.K.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.15 no.4
    • /
    • pp.509-515
    • /
    • 2002
  • Copper deficiency was induced in eight male buffalo calves by adding molybdenum (30 ppm wet basis) to their diet. Copper status was monitored from the liver copper concentration and a level below 30 ppm (DM basis) was considered as deficient. Haemoglobin, haematocrit, total and differential leucocyte numbers were determined. The functions of peripheral neutrophils were assessed by in vitro phagocytosis and killing of Staphylococcus aureus. The effect of molybdenum induced copper deficiency on bone marrow was monitored. The mean total leucocyte count was unaffected whereas a significant fall in neutrophil count coincided with the fall in hepatic copper level to $23.9{\pm}2.69$ ppm. Reduced blood neutrophil numbers was not accompanied by any change in the proportion of different neutrophil precursor cells in bone marrow. It was hypothesised that buffalo calves were more tolerant to dietary molybdenum excess than cattle. It was concluded that neutropenia in molybdenum induced copper deficiency occurred without any effect on their synthesis and maturation process. Bone marrow studies in healthy calves revealed higher percentage of neutrophilic myelocytes and metamyelocytes as compared to cattle.

Photoperiodic Floral Induction in Pharbitis Cotyledons Affected by Polyamines and Ethylene

  • Jueson Maeng
    • Journal of Plant Biology
    • /
    • v.38 no.3
    • /
    • pp.227-234
    • /
    • 1995
  • Exogenous putrescine of 0.5 mM or higher concentratons applied during a 16 h inductive dark period could elevate putrescine content in cotyledons of Pharbitis nil Choisy cv. Violet, a short-day plant, resulting in complete blocking of photoperiodic floral induction. Titers of putrescine, spermidine and spermine in the cotyledons were traced throughout a 16 h dark period. While non-induced cotyledons under continous light slightly increased levels of polyamines, induced tissue maintaiend its putrescine, spermidine and spermine levels as low as 66.4%, 60.9% and 84.9% of non-induced levels respecitvely. Endogenous polyamines kept at lower levels in the inductive dark period were found to upsurge by a night break treatment of 10 min light in the middle of the dark and consequently the inductive dark effect was canceled. Elevation of polyamine titers could also be induced by 100 $\mu$L/L ethylene treatment which completely suppressed floral induction. Compared to untreated cotyledons, ehtylene-treated tissues increased putrescine content by as much as 136.5% in 12 h and spermidine level by up to 130.1% in 8 h. Ethylene-treated cotyledons not only increased endogenous polyamine content but also liberate ethylene in the second half of the inductive dark period accumulating up to three to fourfold level supporting a hypothesis that ethylene-treated tissues are stimulated to produce ethylene which in turn accelerates polyamine biosynthesis in the tissues. It is postulated that substantially low polyamine titers in the inductive dark period would be one of the necessary factors controlling photoperiodic induction of flowering in Pharbitis nil and the inhibitory effects of night break and exogenous ethylene treatment may be atributed to their action to stimulate endogenous polyamine production.

  • PDF

Involvement of PI3K and MMP1 in PDGF-induced Migration of Human Adipose-derived Stem Cells

  • Lim, Yoonhwa;Lee, Minji;Jeong, Hyeju;Kim, Haekwon
    • Development and Reproduction
    • /
    • v.21 no.2
    • /
    • pp.167-180
    • /
    • 2017
  • Human adult stem cells have widely been examined for their clinical application including their wound healing effect in vivo. To function as therapeutic cells, however, cells must represent the ability of directed migration in response to signals. This study aimed to investigate the mechanism of platelet-derived growth factor (PDGF)-induced migration of the human abdominal adipose-derived stem cells (hADSCs) in vitro. A general matrix metalloproteinase (MMP) inhibitor or a MMP2 inhibitor significantly inhibited the PDGF-induced migration. PDGF treatment exhibited greater mRNA level and denser protein level of MMP1. The conditioned medium of PDGF-treated cells showed a caseinolytic activity of MMP1. Transfection of cells with siRNA against MMP1 significantly inhibited MMP1 expression, its caseinolytic activity, and cell migration following PDGF treatment. Phosphatidylinositol 3-kinase (PI3K) inhibitor reduced the migration by about 50% without affecting ERK and MLC proteins. Rho-associated protein kinase inhibitor mostly abolished the migration and MLC proteins. The results suggest that PDGF might signal hADSCs through PI3K, and MMP1 activity could play an important role in this PDGF-induced migration in vitro.