• Title/Summary/Keyword: beta-function

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Amelioration of Cognitive Dysfunction in APP/PS1 Double Transgenic Mice by Long-Term Treatment of 4-O-Methylhonokiol

  • Jung, Yu-Yeon;Lee, Young-Jung;Choi, Dong-Young;Hong, Jin Tae
    • Biomolecules & Therapeutics
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    • v.22 no.3
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    • pp.232-238
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    • 2014
  • Alzheimer's disease (AD) is the most common neurodegenerative disease without known ways to cure. A key neuropathologic manifestation of the disease is extracellular deposition of beta-amyloid peptide (Ab). Specific mechanisms underlying the development of the disease have not yet been fully understood. In this study, we investigated effects of 4-O-methylhonokiol on memory dysfunction in APP/PS1 double transgenic mice. 4-O-methylhonokiol (1 mg/kg for 3 month) significantly reduced deficit in learning and memory of the transgenic mice, as determined by the Morris water maze test and step-through passive avoidance test. Our biochemical analysis suggested that 4-O-methylhonokiol ameliorated $A{\beta}$ accumulation in the cortex and hippocampus via reduction in beta-site APP-cleaving enzyme 1 expression. In addition, 4-O-methylhonokiol attenuated lipid peroxidation and elevated glutathione peroxidase activity in the double transgenic mice brains. Thus, suppressive effects of 4-O-methylhonokiol on $A{\beta}$ generation and oxidative stress in the brains of transgenic mice may be responsible for the enhancement in cognitive function. These results suggest that the natural compound has potential to intervene memory deficit and progressive neurodegeneration in AD patients.

Rossby Waves and Beta Gyre Associated with Tropical Cyclone-scale Barotropic Vortex on the Sphere

  • Nam, Ye-Jin;Cheong, Hyeong-Bin
    • Journal of the Korean earth science society
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    • v.41 no.4
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    • pp.344-355
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    • 2020
  • Tropical cyclone scale vortices and associated Rossby waves were investigated numerically using high-resolution barotropic models on the global domain. The equations of the barotropic model were discretized using the spectral transform method with the spherical harmonics function as orthogonal basis. The initial condition of the vortex was specified as an axisymmetric flow in the gradient wind balance, and four types of basic zonal states were employed. Vortex tracks showed similar patterns as those on the beta-plane but exhibited more eastward displacement as they moved northward. The zonal-mean flow appeared to control not only the west-east translation but also the meridional translation of the vortex. Such a meridional influence was revealed to be associated with the beta gyre and the Rossby wave, which are formed around the vortex due to the beta effect. In the case of the basic zonal state of climatological mean, the meridional translation speed reached the maximum value when the vortex underwent recurving.

Mitochondrial Complex I Inhibition Accelerates Amyloid Toxicity

  • Joh, Yechan;Choi, Won-Seok
    • Development and Reproduction
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    • v.21 no.4
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    • pp.417-424
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    • 2017
  • Alzheimer's disease (AD) is neurodegenerative disease, characterized by the progressive decline of memory, cognitive functions, and changes in personality. The major pathological features in postmortem brains are neurofibrillary tangles and amyloid beta ($A{\beta}$) deposits. The majority of AD cases are sporadic and age-related. Although AD pathogenesis has not been established, aging and declining mitochondrial function has been associated. Mitochondrial dysfunction has been observed in AD patients' brains and AD mice models, and the mice with a genetic defect in mitochondrial complex I showed enhanced $A{\beta}$ level in vivo. To elucidate the role of mitochondrial complex I in AD, we used SH-SY5Y cells transfected with DNA constructs expressing human amyloid precursor protein (APP) or human Swedish APP mutant (APP-swe). The expression of APP-swe increased the level of $A{\beta}$ protein in comparison with control. When complex I was inhibited by rotenone, the increase of ROS level was remarkably higher in the cells overexpressing APP-swe compared to control. The number of dead cell was significantly increased in APP-swe-expressing cells by complex I inhibition. We suggest that complex I dysfunction accelerate amyloid toxicity and mitochondrial complex I dysfunction in aging may contribute to the pathogenesis of sporadic AD.

Induction of Integrin Signaling by Steroid Sulfatase in Human Cervical Cancer Cells

  • Ye, Dong-Jin;Kwon, Yeo-Jung;Shin, Sangyun;Baek, Hyoung-Seok;Shin, Dong-Won;Chun, Young-Jin
    • Biomolecules & Therapeutics
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    • v.25 no.3
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    • pp.321-328
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    • 2017
  • Steroid sulfatase (STS) is an enzyme responsible for the hydrolysis of aryl and alkyl sulfates. STS plays a pivotal role in the regulation of estrogens and androgens that promote the growth of hormone-dependent tumors, such as those of breast or prostate cancer. However, the molecular function of STS in tumor growth is still not clear. To elucidate the role of STS in cancer cell proliferation, we investigated whether STS is able to regulate the integrin signaling pathway. We found that overexpression of STS in HeLa cells increases the protein and mRNA levels of integrin ${\beta}1$ and fibronectin, a ligand of integrin ${\alpha}5{\beta}1$. Dehydroepiandrosterone (DHEA), one of the main metabolites of STS, also increases mRNA and protein expression of integrin ${\beta}1$ and fibronectin. Further, STS expression and DHEA treatment enhanced phosphorylation of focal adhesion kinase (FAK) at the Tyr 925 residue. Moreover, increased phosphorylation of ERK at Thr 202 and Tyr 204 residues by STS indicates that STS activates the MAPK/ERK pathway. In conclusion, these results suggest that STS expression and DHEA treatment may enhance MAPK/ERK signaling through up-regulation of integrin ${\beta}1$ and activation of FAK.

Myocardial Function and Metabolic Energetics in Low Flow Ischemia and with $\beta$-Adrenergic Stimulation in Spontaneously Hypertensive Rat Hearts

  • Kang, Young-Hee;Kang, Jung-Sook;Park, Han-Yoon
    • Preventive Nutrition and Food Science
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    • v.6 no.1
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    • pp.43-50
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    • 2001
  • The effects of cardiac ischemia-reperfusion and $\beta$-adrenergic stimulation on metabolic function and energetics were investigated in Lan gendorff-perfused spontaneously hypertensive rat (SHR) hearts. Sarcoplasmic reticulum {TEX}$Ca^{2+}${/TEX}-dependent ATPase and cardiac lactate dehydrogenase (LDH) are additionally studied. The perfusion medium (1.0 mM {TEX}$Ca^{2+}${/TEX}) contained 5 mM glucose(+5 U/L insulin) and 2 mM pyruvate as substrates. Global ischemia was induced by reducing perfusion pressure of 100 to 40 cm {TEX}$H_{2}${/TEX}O, followed by 20 min reperfusin. Isoproterenol (ISO, 1$\mu$M) was infused for 10 min. Coronary vascular resistance and myocardial oxygen consumption ({TEX}$MVO_{2}${/TEX}) of SHR were increased in parallel with enhanced venous lactate during ischemia and reperfusion compared to those of Sprague Dawley (SD) hearts. Although ischemia-induced increase in venous lactate and combined adenosine plus inosine was abolished, coronary vasodilation produced in SD during reperfusion. In SHR, depressed reactive hyperemia was associated with a fall in cardiac ATP and CrP/Pi ratio and a rise in intracellular lactate/Pyruvate ratio. On the other hand, ISO produced coronary functional hyperemia and an increase in {TEX}$MVO_{2}${/TEX}. However, these responses were less than those in SHR hearts. The ATPase activity of SHR was attenuated in free {TEX}$Ca^{2+}${/TEX} concentrations used under basal condition and with ISO compared to that of SD. Venous lactate output and cardiac LDH activity were augmented in SHR as influenced by ISO. These results demonstrate that coronary reactive and functional hyperemia was dpressed in SHR, which cold be explained by alterations in the cytosolic phosphorylation potential and the cytosolic redox state manipulated by LDH, and by abnormal free calcium handling.

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Effect of Job's Tear(Yul-Moo) Extracts on Mouse Spleen and $IL-1{\beta},\;IL-6,\;TNF-{\alpha}$ Cytokine Production by Peritoneal Macrophages (4주 동안의 율무 추출물 투여가 사이토카인 $IL-1{\beta},\;IL-6,\;TNF-{\alpha}$ 생성과 비장세포 증식에 미치는 영향)

  • Ryu Hye-Sook;Kim Hyun-Sook
    • The Korean Journal of Food And Nutrition
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    • v.19 no.2
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    • pp.201-206
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    • 2006
  • Numerous investigators have studied various activities of natural products and have found that they have not only nutritional effects, but also beneficial properties to cure various diseases and to maintain good health. Job's Tear(Yul-Moo) is a grass crop that has long been used in traditional medicine and as a nourishing food. Although its mechanism of action remains unclear, Job's Tear has been reported to exhibit anti-inflammatory, stomachic, anti-allergic, and anti-spastic effects and has been used in China for the treatment of warts, rheumatism, and neuralgia. Previous results in our laboratory demonstrated that the ethanol extract and the water extract of Job's Tear exerted an immune regulatory function on mice cells in vitro. The present study was performed to investigate the ex vivo effect of Job's Tear on immune function. Seven to eight weeks old mice(Balb/c) were fed chow diet ad libitum and water extract of Job's Tear was administered orally every other day for four weeks at two different concentrations(50 and 500mg/kg B.W.). Splenocytes proliferation with mitogen stimulation with Con A and LPS was enhanced at 50 mg/kg B.W. of Job's Tear compared to those of the control group. The results of this ex vivo study showed that proliferation of splenocytes and macrophage activation were seen in the mice orally administrated 50 mg/kg B.W. of Job's Tear water extracts. In conclusion, this study suggests that Job's Tear extracts may enhance immune function by regulating splenocyte proliferation and the cytokine prodution capacity of activated macrophages in mice.

Factors Influencing Medication Adherence and Status of Medication Use of the Elderly with Chronic Disease Taking Non-opioid Analgesics (만성질환 관련 비마약성 진통제 처방 노인의 약물사용 실태 및 약물복용이행에 영향을 미치는 요인)

  • Jeon, Hae Ok;Kim, Bockryun;Kim, Haesook;Chae, Myung-Ock;Kim, Myeong Ae;Kim, Ahrin
    • Journal of Korean Biological Nursing Science
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    • v.19 no.1
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    • pp.18-29
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    • 2017
  • Purpose: This study investigates the status of medication use of the elderly with chronic disease taking non-opioid analgesics and attempts to identify factors influencing medication adherence. Methods: Data were collected from September 1 to October 19, 2016. A structured questionnaire was used for face-to-face interview with a convenience sample of 161, elderly people with chronic disease taking non-opioid analgesics. The survey included questions about status of medication use, medication adherence, symptom experience, depression and family function. Data were analyzed using descriptive statistics, t-tests, ANOVA, Pearson's correlation coefficients, and stepwise multiple regression with IBM SPSS 23.0 program. Results: The mean score of medication adherence of the elderly with chronic disease was $4.48{\pm}2.35$. Experiences of side effects (${\beta}=.31$, p< .001), use of over-the-counter pain medication (${\beta}=.19$, p= .009), and family function (${\beta}=.16$, p= .031) were identified as significant predictors. The final model explained 18.0% of the variation of medication adherence of the elderly with chronic disease taking non-opioid analgesics (F= 12.30, p< .001). Conclusion: Therefore, as a strategy to improve medication adherence of the elderly with chronic disease, therapeutic intervention should be developed to improve family function and to manage with personalized plans considering experiences of side effects and use of over-the-counter pain medication.

The Eigenvalues and Their Relationships for the Rectangular Frame (4각형 골조의 고유치와 고유치 간의 관계)

  • Lee, Soo-Gon;Kim, Soon-Cheol;Song, Chang-Young;Song, Sang-Yong
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.9 no.3
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    • pp.139-150
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    • 2005
  • Finite element method is applied to the determinations of the two eigenvalues(the elastic critical load and the natural frequence of lateral vibrations) of single story-3 equal bay rectangular frame. The analysis parameters are taper parameter ${\alpha}$ for column, and beam span to column height ratio, ${\beta}$ and second moment area ratio of beam to column, ${\Upsilon}$. Support condition at the column base and sway condition at the column top are also considered in the stability analysis of frame. The changes in the coefficient of eigenvalue are represented by algebraic function of analysis parameter. The coefficients estimated by the proposed algebraic function show good agreement with those determined by finite element method, which suggest the design aid role of the proposed function. By increasing the column axial forces step by step, the corresponding frequencies are also determined, which makes one examine or confirm the relationship suggested by other studies.

Effects of Sagunjatang-Gami on Uterine and Ovarian Function in the Ovariectomized Rat Postmenopause Model (사군자탕가미방(四君子湯加味方)이 난소적출 폐경 병태 모델의 자궁 및 난소 기능에 미치는 영향)

  • Maeng, Yu-Sook;Choi, Min-Sun;Ahn, In-Suk;Kim, Dong-Il
    • The Journal of Korean Obstetrics and Gynecology
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    • v.25 no.4
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    • pp.12-26
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    • 2012
  • Objectives: The purpose of this study is to examine the effects of Sagunjatang-Gami(SGJT) on uterine and ovarian function in the ovariectomized rat postmenopause model. Methods: SGJT was administered in ovariectomized Wister albino female rats for three month. After that, uterine weight, uterine index, serum estradiol-$17{\beta}$ levels and phosphorylation of ERK or AKT, and histological analysis of uterus were measured to assess the impact on uterine and ovarian function in ovariectomized rats. In addition, phosphorylation of $ER{\alpha}$, ERK, AKT by SGJT in MDA-MB-231 cells were measured. To identify safety of SGJT, the cell cytoxicity in MDA-MB-231 cells and serum GOT, GPT levels were measured in ovariectomized rats. Results: The results were as follows. 1. SGJT decreased the viability of MDA-MB-231 cells in a dose-dependent manner. 2. The level of serum GOT, GPT in SGJT-treated group showed significant decrease in comparison with control group. 3. Phosphorylation of $ER{\alpha}$, ERK, AKT by SGJT in MDA-MB-231 cells were increased. 4. Uterus index in SGJT-treated group showed significant increase in comparison with control group. The level of serum estradiol-$17{\beta}$ in SGJT-treated group showed significant increase in comparison with control group. Phosphorylation of ERK or AKT by SGJT in the uterus of ovariectomized rats was increased significantly. 5. Uterus index and the level of serum estradiol-$17{\beta}$ in SGJT-treated group increased at higher rates in comparison with estrogen-treated group. Conclusions: Taken together, we suggest that SGJT has been shown to be effective in preventing postmenopausal uterine and ovarian degeneration and curing postmenopausal low estrogen related symptoms.

Anti-Fibrotic Effects by Moringa Root Extract in Rat Kidney Fibroblast (모링가 뿌리 추출물에 대한 신장섬유화 억제 효과)

  • Park, Su-Hyun;Chang, Young-Chae
    • Journal of Life Science
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    • v.22 no.10
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    • pp.1371-1377
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    • 2012
  • Fibrosis in kidney by internal and external factors causes progressive loss of renal function. Renal fibrosis is the inevitable consequence of an excessive accumulation of the extracellular matrix. TGF-${\beta}$ plays an important role in the process of renal fibrosis and stimulates the synthesis of profibrotic factors, including collagens, fibronectin, and plasminogen activator inhibitor (PAI-1). We examined the effect of Moringa oleifera Lam (moringa) extracts in a rat kidney fibrosis model. We found that moringa root extract suppresses protein expression/mRNA levels of Type I collagen, fibronectin, and PAI-1 induced by TGF-${\beta}$ in renal fibroblasts. Moringa root extract selectively inhibited phosphorylation of TGF-${\beta}$-induced $T{\beta}RII$ and the downstream signaling pathway (e.g., Smad4), and phospho-ERK, but not JNK, p38, or PI3K/AKT. These results suggest that moringa root extract can act against TGF-${\beta}$-induced renal fibrosis in rat kidney fibroblast cells by a mechanism related to its antifibrotic activity, which regulates expression of fibronectin, Type I collagen, and PAI-1 through $T{\beta}RII$-Smad2/3-Smad4 and ERK. Therefore, moringa root extract is an effective substance for fibrosis therapy and provides a new therapeutic strategy for diseases associated with elevated profibrotic factor synthesis.