• 제목/요약/키워드: Heat Accumulation

검색결과 226건 처리시간 0.033초

Ginsenoside (20S)Rg3 Ameliorates Synaptic and Memory Deficits in an Animal Model of Alzheimer's Disease

  • Kim, Tae-Wan
    • 한국약용작물학회:학술대회논문집
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    • 한국약용작물학회 2011년도 추계학술발표회
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    • pp.31-45
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    • 2011
  • The amyloid ${\beta}$-peptide ($A{\beta}$), which originates from the proteolytic cleavage of amyloid precursor protein (APP), plays a central role in the pathogenesis of Alzheimer's disease (AD). Mounting evidence indicates that different species of $A{\beta}$, such as $A{\beta}$ oligomers and fibrils, may contribute to AD pathogenesis via distinct mechanisms at different stages of the disease. Importantly, elevation and accumulation of soluble $A{\beta}$ oligomers closely correlate with cognitive decline and/or disease progression in animal models of AD. In agreement with these studies, oligomers of $A{\beta}$ have been shown to directly affect synaptic plasticity, a neuronal process that is known to be essential for memory formation. Our previous studies showed that $A{\beta}$ induces the breakdown of phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), a phospholipid that regulates key aspects of neuronal function. PI(4,5)P2 breakdown was found to be a key step toward synaptic and memory dysfunction in a mouse model of AD. To this end, we seek to identify small molecules that could elevate the levels of PI(4,5)P2 and subsequently block $A{\beta}$ oligomer-induced breakdown of PI(4,5)P2 and synaptic dysfunction.. We found that (20S)Rg3, an active triterpene glycoside from heat-processed ginseng, serves as an agonist for phosphatidylinositol 4-kinase IIalpha (PI4KIIalpha), which is a lipid kinase that mediates a rate-limiting step in PI(4,5)P2 synthesis. Consequently, (20S)Rg3 stimulates PI(4,5)P2 synthesis by directly stimulating the activity of PI4KIIalpha. Interestingly, treatment of a mouse model of AD with (20S)Rg3 leads to reversal of memory deficits. Our data suggest that the PI(4,5)P2-promoting effects of (20S)Rg3 may help mitigate the cognitive symptoms associated with AD.

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Proteome Analysis of Paenibacillus polymyxa E681 Affected by Barley

  • Seul, Keyung-Jo;Park, Seung-Hwan;Ryu, Choong-Min;Lee, Yong-Hyun;Ghim, Sa-Youl
    • Journal of Microbiology and Biotechnology
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    • 제17권6호
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    • pp.934-944
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    • 2007
  • Paenibacillus polymyxa E681 is known to be able to suppress plant diseases by producing antimicrobial compounds and to promote plant growth by producing phytohormones, and secreting diverse degrading enzymes. In spite of these capabilities, little is known regarding the flow of information from the bacterial strain to the barley roots. In an attempt to determine the flow of information from the bacterial strain to barley roots, the strain was grown in the presence and absence of barley, and two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and MALDI-TOF mass spectrometry were used. 2D-PAGE detected approximately 1,000 spots in the cell and 1,100 spots in the supernatant at a pH 4-10 gradient. Interestingly, about 80 spots from each sample showed quantitative variations. Fifty-three spots from these were analyzed by MALDI-TOF mass spectrometry and 28 proteins were identified. Most of the cytosolic proteins expressed at higher levels were found in P. polymyxa E681 cells grown in the presence of barley rather than in the absence of barley. Proteins detected at a lower level in the surpernatant of P. polymyxa E68l cells grown in the presence of barley were lipoprotein, glucose-6-phosphate 1-dehydrogenase, heat-shock protein HtpG, spermidine synthase, OrfZ, ribonuclease PH, and coenzyme PQQ synthesis protein, and flagellar hook-associated protein 2 whereas proteins detected at a higher level in the surpernatant of P. polymyxa E681 cells grown in the presence of barley included D-alanyl-D-alanine ligase A, isopentenyl-diphosphate delta-isomerase, ABC transporter ATP-binding protein Uup, lipase. Many of the proteins belonging to plant-induced stimulons are associated with biosynthetic metabolism and metabolites of proteins and transport. Some of these proteins would be expected to be induced by environmental changes resulting from the accumulation of plant-secreted substances.

시간지연 모델의 적용을 통한 수소/공기 확산화염의 음향파 응답 분석 (A Numerical Analysis of Acoustic-Pressure Response of H2-Air Diffusion Flames with Application of Time-Lag Model)

  • 손채훈;임준석
    • 한국추진공학회지
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    • 제16권1호
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    • pp.1-8
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    • 2012
  • 희석된 수소-공기 확산화염의 응향 응답 특성을 저압과 고압 영역에서의 화염 구조 해석을 토대로 수치적으로 조사하였다. 음향 주파수가 증가함에 따라 어느 압력 영역에서든 열방출율의 비선형 축적현상에 의해 유한 화학반응의 효과가 증진된다. 이는 결국 높은 음향 증폭으로 이어지게 된다. 동일한 계산 결과를 압력 감응 시간지연 모델에 의해 재해석하였다. 시간 지연 모델의 적절한 적용을 통해, 각 압력 영역에서 시간지연과 간섭지수 인자가 정량화되었다. 음향 증폭의 정도를 나타내는 간섭지수는 어느 압력 영역에서든 1000 Hz 근처에서 최고값을 나타내었고, 고압영역에서 화염이 더 불안정한 응답을 보였다. 음향 주파수에 따른 간섭지수의 변화 경향은 기존의 증폭지수 변화 경향과 잘 일치하였다.

The Longevity Properties of 1,2,3,4,6-Penta-O-Galloyl-β-D-Glucose from Curcuma longa in Caenorhabditis elegans

  • Ahn, Dalrae;Cha, Dong Seok;Lee, Eun Byeol;Kim, Ban Ji;Lee, So Yeon;Jeon, Hoon;Ahn, Min-Sil;Lim, Hye Won;Lee, Heon Yong;Kim, Dae Keun
    • Biomolecules & Therapeutics
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    • 제21권6호
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    • pp.442-446
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    • 2013
  • Here in this study, we isolated 1,2,3,4,6-penta-O-galloyl-${\beta}$-D-glucose (PGG) from Curcuma longa L. and elucidated the lifespan-extending effect of PGG using Caenorhabditis elegans model system. In the present study, PGG demonstrated potent lifespan extension of worms under normal culture condition. Then, we determined the protective effects of PGG on the stress conditions such as thermal and oxidative stress. In the case of heat stress, PGG-treated worms exhibited enhanced survival rate, compared to control worms. In addition, PGG-fed worms lived longer than control worms under oxidative stress induced by paraquat. To verify the possible mechanism of PGG-mediated increased lifespan and stress resistance of worms, we investigated whether PGG might alter superoxide dismutase (SOD) activities and intracellular ROS levels. Our results showed that PGG was able to elevate SOD activities of worms and reduce intracellular ROS accumulation in a dose-dependent manner.

Electrosurgery를 이용한 치료증례 (ELECTROSURGERY IN DENTAL PRACTICE-A CASE REPORT)

  • 윤재웅;이상훈;이광수;한세현
    • 대한소아치과학회지
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    • 제23권3호
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    • pp.631-639
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    • 1996
  • Electrosurgical technique have been used in dentistry as an aid to soft tissue management for nearly 60 years. However, it was not until the late 1960s that the principles of electrosurgery were understood and improved equipment became available. Electrosurgery is a surgical procedure performed on soft tissue utilizing controlled high frequency electricaI(radio-frequency) currents in the range of 1,500,000 to 7,500,000 cyclesper second. The radio-frequency energy used in electrosurgery is able to cut and coagulate tissue because it focuses the energy at the small, active electrode. Advantages of electrosurgery for soft-tissue management during dental procedures include improved hemostasis, ease of tissue modification, improved visibility and so on, but adverse healing responses-including necrosis of soft tissue and sequestration of alveolar bone-have been reported. The present report provides examples of treatment of soft tissue and pulp tissue of primary teeth by electrosurgery. The results are as follows; 1. Electrosurgical techniques can be used for various procedures in pedodontics. 2. Electrosurgical procedures provide improved hemostasis and visibility in the operating field, which enable to remove, reshape, and contour soft tissues easily. 3. In pulpotomy technique, it was difficult to expect the variable pulpal response based on the degree of heat accumulation and the conditions of pulp tissues. Therefore, electrosurgical pulpotomy could not be considered as a method superior to formocresol pulpotomy. 4. A greater degree of dexterity and experiences in manipulation of the electrode is required compared with the conventional scalpel surgery.

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한약(韓藥)의 면역조절(免疫調節) 작용(作用)을 통(通)한 종양치료(腫瘍治療)에 대(對)한 연구(硏究) (The effects of immune activating herbs on the anti-tumor activity)

  • 이정수;이연월;조정효;손창규;유화승;조종관
    • 대한한방종양학회지
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    • 제9권1호
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    • pp.65-73
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    • 2003
  • The researches for tumor and the developments for new anti-tumor medicine are being continuously developed in the oriental as well as the west. The principles therapy of anti-tumor activity was based on knowledge of the method of support the healthy energy and strengthen the body resistance, promote blood circulation to remove blood stasis, clear away heat and toxic materials, dissipate phlegm and disperse the accumulation of evils. But the major clinical features of tumor was to be considered in developing a treatment plan include (1) distinguish between clinical and pathologic staging - acute and chronic, (2) classification of pathologic pattern, and (3) distinction of body situation : for examples asthenia - sthenia etc. It was most important to distinguish between supporting the healthy and eliminating the evil factors and to treat differently at the root and the branch cause of a neoplasm. In clinical study and experimental study, the effects of oriental medicine could be summarized as three that were decreasing toxicity of chemo-therapy, directly suppressing and killing cancerous cell and increasing chemo-effect through preventing metastasis. Improving organic immunity with oriental medicine could be summarized as five that were promoting phagocytosis of macrophage, inducing interferon, promoting formation of immnoglobulin, increasing number of T-cell and promoting transformation of lymphocyte. It is suggested that effective use of immune activating herbs inhibited metastasis and decreased recurrence and then we were able to expect increasing survival rate and improving clinical symptoms and quality of life(QOL) of tumor patients.

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ADHD의 과잉활동성, 주의력결핍 증후에 대한 한의학적 고찰 - 동의보감을 중심으로 - (A Study on the Oriental - medical Understanding about Inattention, Hyperactivity sympton in ADHD(attention Deficit Hyperactivity Disorder) - Within Don yui bo gam Book -)

  • 박재현;박재형;김진형;김태현;류영수;강형원
    • 동의신경정신과학회지
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    • 제15권1호
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    • pp.9-25
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    • 2004
  • Behavioral characteristics of Attention Deficit Hyperactivity Disorder(ADHD) is one of the most common mental disorders among children.child psyachiatry. Inattention, Hyperactivity that is done by hyperkinesis or minimal brain dysfunction is major sypmton in ADHD, But etiology and pathological facor of ADHD is very much or unkown.. We brought to about a Study on the Oriental - medical pathologic Understanding about Inattention, Hyperactivity symptom in ADHD within Don yui bo gam Book are as follows. 1. Oriental medical pathologic concepts about Inattention, Hyperactivity are continuous with process of Yang Qi(陽氣), an unbalance of qi(氣) and shen ming(神明), excess of seven emotions(七情), pathology of Huo(火). 2. Immanent factors in inattention, Hyperactivity are improper diet, overtiredness and seven emotions, are continuous with pathological process of the heart, liver, gall bladder, spleen, stomach, kidneys. 3. In oriental medicine, considered as a child's qi of shao yang, dynamic physiological feature, excess and want of yin and yang, organs and bowels, immanently imbalance in growth rather than a child's mental disorder 4. Inattention, looseness in ADHD-PI type are continuous with forgetfulness, improper overtiredness, shortage of qi, the interior heat syndrome due to yin deficiency within Don yui bo gam Book 5. Hyperactivity, impulsive actions in ADHD-C type are continuous with sudden palpitation, severe palpitation, delirium, fidgeting due to deficiency, fidgetiness, hyperactivity of huo due to yin deficiency, fever, febrile disease with accumulation of blood.

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팥에서 분리한 Genistin이 선충의 수명연장에 미치는 영향 (Effects of genistin from Vigna angularis on Lifespan-extending in Caenorhabditis elegans)

  • 이은별;안달래;김반지;이소연;차연수;김민아;송석보;김대근
    • 생약학회지
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    • 제46권1호
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    • pp.17-22
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    • 2015
  • Previous phytochemical studies of Vigna angularis (Ohwi) Ohwi & Ohashi (Leguminosae) have shown the presence of saponins and flavonoids. From the seed of V. angularis, genistein-7-O-${\beta}$-D-glucopyranoside (genistin) was isolated. Lifespan-extending effect of genistin was elucidated using Caenorhabditis elegans model system. Genistin showed potent lifespan extension of worms under normal culture condition. This compound also exhibited the protective effects against thermal and oxidative stress conditions. In the case of heat stress, genistin-treated worms exhibited enhanced survival rate, compared to control worms. In addition, genistin-fed worms lived longer than control worms under oxidative stress induced by paraquat. To verify the possible mechanism of genistin-mediated increased lifespan and stress resistance of worms, we investigated whether genistin might alter superoxide dismutase (SOD), catalase activities and intracellular ROS levels. Our results showed that genistin was able to elevate SOD and catalase activities of worms and reduce intracellular ROS accumulation in a dose-dependent manner.

APS법에 의한 경사기능성 지르코니아 열장벽 피막의 열충격 및 고온내마모 특성에 관한 연구 (A Study in the High Temperature Wear and Thermal Shock Resistance of the Functional Gradient Thermal Barrier Coating by Air Plasma Spray with ZrO$_2$)

  • 한추철;박만호;송요승;변응선;노병호;이구현;권식철
    • 한국표면공학회지
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    • 제30권4호
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    • pp.272-280
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    • 1997
  • The Thermal Barrier Coation(TBC) to improve the that barrier and wear resistant propenrty in high temperature ofthe aircraftength between the accumlation of the aircraft engine and the automobile engine has usually the two layer structure. One is a creamic top layer for heat insulation and the other is a metal bond layer to facilitate the bond strength between the top ceramic layer and the substrate. But, the coated layers should be peeled off because of the accumulation of the thermal stress by the differance of the thermal expantion coefficient between metal and ceramics in a hrat cyclic environment. In this study, the intermediate layer by plasm spray process was introduced to reduce the thermal stress. The powders of plasm spray coating were the Yttria Stabilized Zirconia (YSZ), the Magnesia Stabillized Zirconia(MSZ) and NiCrAlY. the intermediate layer was sprayed with the powders of the bond cast for the purpose of test were executed. The high temperature wear resistance tends to decreasnceee wear and thermal shock test were exeucuted. The high temperature were resistance of the YSZ TBC is better that of the MSZ TBC. The wearrsistance tends to decrease accoring to incresing the temperature between $400^{\circ}C$to $600^{\circ}C$. The thermal shock life of the 3 layer TBC with YSZ top casting was the most outstanding thermal shock rsisstasnce. This means that the intermediate layer should play an importnat roll to alleviate the diffrerence of the thermal expansion coef frcients between metallic layer and cermics layer.

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액상분사식 LPG 인젝터의 아이싱 생성 특성 및 억제 방법 (Icing Characteristics in Liquid-Phase Injection of LPG Fuel)

  • 이선엽;김창업;최교남;강건용
    • 한국분무공학회지
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    • 제14권4호
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    • pp.147-152
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    • 2009
  • Since a liquid-phase LPG injection system allows accurate control of fuel injection and increase in volumetric efficiency, it has advantages in achieving higher engine power and lower emissions compared to the mixer type LPG supplying system. However, this system also leads to an unexpected event called icing phenomenon which occurs when moisture in the air near the injector freezes and becomes frost around the nozzle hole due to extraction of heat from surrounding caused by instant fuel vaporization. As a result, it becomes difficult to control air/fuel ratio in engine operation, inducing exacerbation of engine performance and HC emission. One effort to mitigate icing phenomenon is to attach anti-icing injection tip in the end of nozzle. Therefore, in this study, the effect of engine operation parameters as well as surrounding conditions on icing phenomenon was investigated in a bench test rig with commercially-used anti-icing injection tips. The test results show that considerable ice was deposited on the surface near the nozzle hole of the anti-icing tip in low rpm and low load operating conditions in ambient air condition. This is because acceleration of detachment of deposited ice from the tip surface was induced in high load, high rpm conditions, resulting in decrease in frost accumulation. The results of the bench testing also demonstrate that little or no ice was formed at surrounding temperature below a freezing point since the absolute amount of moisture contained in the intake air is too small in such a low temperature.

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