• Title/Summary/Keyword: blockage effects

Search Result 141, Processing Time 0.025 seconds

Cell Cycle Arrest by Sabaek-san is Associated with induction of Cdk Inhibitor p21 in Human Lung Cancer A549 Cells (사백산에 의한 인체 폐암세포의 G1기 성장억제기전에 관한 연구)

  • Kang Byong Ryeung;Oh Chang Sun;Lee Jae Hun;Choi Yung Hyun;Park Dong Il
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.16 no.6
    • /
    • pp.1177-1183
    • /
    • 2002
  • We investigated the effects of Sabaek-san (SBS) water extract on the cell proliferation of human lung carcinoma A549 cells. SBS treatment resulted in the inhibition of cell proliferation in a concentration-dependent manner. This anti-proliferative effect of A549 cells by SBS treatment was associated with morphological changes such as membrane shrinking and cell rounding up. DNA flow cytometric histograms showed that population of G1 phase of the cell cycle was increased by SBS treatment in a concentration-dependent manner. SBS treatment induced a marked accumulation of tumor suppressor p53 and a concomitant induction of cyclin-dependent kinase (Cdk) inhibitor p21WAF1/CIP, which appears to be transcriptionally upregulated and is p53 dependent. In addition, SBS treatment resulted in down-regulation of cyclooxygenase-2 (COX-2) as determined by RT-PCR analysis. The present results indicated that SBS-induced inhibition of lung cancer cell proliferation is associated with the blockage of G1/S progression the induction of apoptosis.

Vasodilation of Ethanol Extract of Cinnamomi Ramulus via Voltage Dependent $Ca^{2+}$ Channel Blockage (전압의존성 $Ca^{2+}$ 통로 억제를 통한 계지(桂枝) 에탄올 추출물의 혈관이완 효능)

  • Kim, Jong-Bong;Shin, Heung-Mook
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.24 no.4
    • /
    • pp.592-597
    • /
    • 2010
  • Cinnamomi Ramulus is one of the medicinal plants that have been used to improve various diseases caused by insufficient blood circulation. This study was performed for the investigation of vasodilation efficacy ethanol extract of Cinnamomi Ramulus (CR). CR exhibited vascular relaxation against phenylephrine (PE, $10^{-6}M$)-, KCl- and NaF-induced contraction in rat thoracic aorta. In addition, its relaxation was endothelium-independent. Treatment of potassium channel blockers such as gilbenclamide (Gli, $10^{-5}M$), tetraethylammonium (TEA, 1 mM) and 4-aminopyridine (4-AP, 0.2 mM) did not effect on the relaxation of CR. The relaxant effects were also not inhibited by pre-treatment of rat aorta with L-NAME ($10^{-4}M$), methylene blue ($10^{-5}M$), indomethacin ($10^{-5}M$), and atropine ($10^{-6}M$). However, nifedipine ($10^{-5}M$), L-type $Ca^{2+}$ channel blocker, in part attenuated the relaxation of CR ($0.2\;mg/m{\ell}$), but SK&F96365 ($3{\times}10^{-5}M$), receptor activated $Ca^{2+}$ channel blocker and 2-APB ($10^{-4}M$), store operated $Ca^{2+}$ channel blocker did not affact dilation of CR. These findings suggest that the endothelium-independent relaxation effect of CR is partly related with inhibition of $Ca^{2+}$ influx via voltage dependent $Ca^{2+}$ channel.

Numerical Study on the Effects of Pressure Wave Propagation for Tunnel Entrance Shape Change in High-Speed Railways (고속철도의 터널입구 형상변황에 따른 압력파동 현상에 관한 수치적 연구)

  • 목재균;백남욱;유재석;최윤호
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.5 no.2
    • /
    • pp.50-59
    • /
    • 1997
  • When a front head of train enters a tunnel at a high speed, compression wave is generated at tunnel entrance due to the confinement effect and propagated along the tunnel with sound of speed. The propagated compression wave is reflected at tunnel exit due to abrupt pressure change at passage. The reflected wave is expansion pressure wave. And when the rear head of train goes through the tunnel entrance, another expansion pressure wave is generated and propagated along the tunnel. The pressure drop occurs seriously around train when the two expansion pressure waves come cross on train in the tunnel. In order to reduce the pressure drop, the compression wave front must be controlled because the intensity and magnitude of pressure drop is nearly proportional to that of compression wave at tunnel entrance. This study relates to reduction of the pressure wave gradient with respect to tunnel entrance shape change with various kind of angle and rounding. The results show characteristics of wave propagation in tunnel, usefulness of characteristic curve to estimate proper time domain size in numerical study and measuring time in actual experiment. Also rounding is contributed to improve pressure wave front even if its radius is very small at tunnel entrance. In order to improve of pressure wave front at tunnel entrance, proper angle is prefered to rounding with big radius and an angle of around 14$^{\circ}$ is recommended according to this simulations, And it is expected to reduce additional pressure drop in tunnel when the location and the size of the internal space for attendant equipment are considered in advance.

  • PDF

Development of pre-treatment for the injection water into the aquifer storage and recovery(ASR) in Korea: The two-step rapid filter to reduce physical clogging and secure the volume of the injected water (지하저수지(ASR) 유입수 전처리기법 개발: 물리적 폐색 저하 및 수량공급원활을 위한 2 단계 급속여과지)

  • Park, Byeong-Joo;Do, Si-Hyun;Hong, Seong-Ho
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.29 no.3
    • /
    • pp.337-345
    • /
    • 2015
  • Two step rapid filter system as a pre-treatment for the injected water into aquifer storage and recovery (ASR) in Korea was developed to reduce physical blockage and secure the volume of the injected water. First, single rapid sand filters with three different media sizes (0.4~0.7, 0.7~1.0 and 1.0~1.4 mm) were tested. Only two sizes (0.4~0.7 and 0.7~1.0 mm) satisfied target turbidity, below 1.0 NTU. However, they showed the fast head loss. To prevent the fast head loss and secure the volume of the injected water, a rapid anthracite filter with roughing media size (2.0~3.4 mm) were installed before a single rapid sand filter. As results, both the target turbidity and reduction of head loss were achieved. It was determined that the media size for a rapid sand filter in two step rapid filter system (i.e. a rapid anthracite filter before a rapid sand filter) was 0.7~1.0 mm. In addition, the effects of coagulant doses on the removal of natural organic matter (NOM), which might cause a biological clogging, were preliminarily evaluated, and the values of $UV_{254}$, dissolved organic carbon (DOC) and SUVA were interpreted.

A Historical Consideration on the External Treatment theories and diseases for which medicine is efficacious (외치료법(外治療法)의 이론(理論)과 적응증(適應症)에 대한 사적(史的) 고찰(考察))

  • Moon, Woo-Sang;Lee, Byung-Wook;Ahn, Sang-Woo;Kim, Eun-Ha
    • Korean Journal of Oriental Medicine
    • /
    • v.10 no.2
    • /
    • pp.1-21
    • /
    • 2004
  • 1) Objective External treatments have various curative effects. So it had been used to cure various patients. But, it has a limited sphere of application in the present South Korea. Therefore we would like to bring out its sphere of application and detailed method in the oriental medicine classics. 2) Methodologies We have researched external treatment history according to below the procedure. (1) Making a related words list: We have used existing external treatments technical books to make a list. It has been connected with external treatments. It includes not only technical terms, but also general terms. (2) Searching sentence: We have searched sentence that contain terms that related with external treatments. (3) Analysis of related sentence: We have searched and classified sentence by disease. (4) Analysis of external treatment methods. 3) Conclusions From long time ago people have used external treatment to cure various disease. According to the ${\ulcorner}Nei-Jing{\lrcorner}$, hot compress therapy, fumigation therapy and bathing therapy had been used to cure blockage syndrome, muscle disease, carbuncle and cellulitis. Thereafter, a sphere of external treatment had gradually enlarged. (1) After all its sphere had included dermatologic, psychologic, internal, ophthalmic, otolaryngologic, obstetrics, gynecologic, pediatric and surgical diseases. (2) External treatment methods have contained hot compress therapy, fumigation therapy, bathing therapy, application therapy, medication bag therapy, medication plug therapy, medication massotherapy, aroma therapy and so on. (3) Medication types of external treatment have contained ointment, juice, infusion, powder, suppository and so on.

  • PDF

Investigation of Near.Transducer Errors in Acoustic Doppler Current Profiler Measurements Using Experimental and Numerical Method (ADCP 계기 부근에서 발생하는 관측 오차의 실험 및 수치모의에 의한 고찰)

  • Kim, Dong-Su;Kang, Boo-Sik
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.12 no.2
    • /
    • pp.944-951
    • /
    • 2011
  • This paper reports results of a joint experimental and numerical investigation of the causes of near-transducer errors due to the combined effect of acoustic and ADCP-induced flow disturbance near the ADCP transducer. The laboratory study focused on an isolated ADCP (deployment without boat). Measurements of the flow disturbance produced by the ADCP in vertical and horizontal planes were obtained acquiring measurements with an Acoustic Doppler Velocimeter (ADV). Concurrent measurements with ADCP and ADV were made to infer additional near-transducer effects in the ADCP measurements. The numerical investigation was designed to extend the inquiry on the near-transducer potential errors when the ADCP is deployed from a boat. Large Eddy Simulation (LES) was conducted to obtain the extent and magnitude of the disturbances induced by the drag acting on a boat-mounted ADCP and by the blockage effect of the instrument and boat. It is found the velocities measured by the ADCP are biased low and differ substantially from the undisturbed channel flow solution within a limited layer beneath the instrument.

A Study on Wall Interference Effect Around the Wind Turbine Airfoil (풍력터빈 에어포일 주위의 벽면효과에 관한 연구)

  • Cho, Hwan-Kee;Kang, Seung-Hee;Ryu, Ki-Wahn;Lee, Jun-Shin
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.40 no.6
    • /
    • pp.485-491
    • /
    • 2012
  • The wall interference effects around the wind-turbine airfoil are experimentally investigated at low Reynolds numbers in a closed test-section wind tunnel. The test is performed at free-stream velocities from 10 to 31 m/s, which correspond to Reynolds numbers ranging from $1.5{\times}10^5$ to $4.6{\times}10^5$ based on chord of the airfoil. The blockage-area ratios, which is the ratio of the chord to the test-section width, are 27.8%, 38.5%, 41.7%, 45.5%, and 55.6%. The test results for the airfoil show that the transition point on the airfoil surface tends to move backward due to wall interference. The wall pressures for an adequate interference correction by a measured-boundary-condition method are desirable more than three times region of the chord before and after around the reference center.

The effects of limestone powder and fly ash as an addition on fresh, elastic, inelastic and strength properties of self-compacting concrete

  • Hilmioglu, Hayati;Sengul, Cengiz;Ozkul, M. Hulusi
    • Advances in concrete construction
    • /
    • v.14 no.2
    • /
    • pp.93-102
    • /
    • 2022
  • In this study, limestone powder (LS) and fly ash (FA) were used as powder materials in self-compacting concrete (SCC) in increasing quantities in addition to cement, so that the two powders commonly used in the production of SCC could be compared in the same study. Considering the reduction of the maximum aggregate size in SCC, 10 mm or 16 mm was selected as the coarse aggregate size. The properties of fresh concrete were determined by slump flow (including T500 time), V-funnel and J-ring experiments. The experimental results showed that as the amount of both LS and FA increased, the slump flow also increased. The increase in powder material had a negative effect on V-funnel flow times, causing it to increase; however, the increase in FA concretes was smaller compared to LS ones. The increase in the powder content reduced the amount of blockage in the J-ring test for both aggregate sizes. As the hardened concrete properties, the compressive and splitting strengths as well as the modulus of elasticity were determined. Longitudinal and transverse deformations were measured by attaching a special frame to the cylindrical specimens and the values of Poisson's ratio, initiation and critical stresses were obtained. Despite having a similar W/C ratio, all SCC exhibited higher compressive strength than NVC. Compressive strength increased with increasing powder content for both LS and FA; however, the increase of the FA was higher than the LS due to the pozzolanic effect. SCC with a coarse aggregate size of 16 mm showed higher strength than 10 mm for both powders. Similarly, the modulus of elasticity increased with the amount of powder material. Inelastic properties, which are rarely found in the literature for SCC, were determined by measuring the initial and critical stresses. Crack formation in SCC begins under lower stresses (corresponding to lower initial stresses) than in normal concretes, while critical stresses indicate a more brittle behavior by taking higher values.

Experimental Study on Energy Transmission Rate of Horizontal Dual Plate by Random Wave System (수평형(水平型) 이열(二列) 조합판(組合板)의 투과율(透過率) 산정(算定)을 위한 실험적(實驗的) 연구(硏究))

  • Kweon, Hyuck-Min;Kim, Young-Hak;Kee, Sung Tae
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.28 no.4B
    • /
    • pp.421-428
    • /
    • 2008
  • For last decades, the rapid coastal erosion process spreading along Korean peninsular has become a nuisance especially for tourism and local economy. Global warming and sea-level rise demand persistently new coastal protection strategies against the conventional methods using armored structures. In a view of this, Kweon et al. (2007) has proposed a new type of horizontal steel plates for an ideal candidate as eco-friendly detached breakwater systems for global warming era. The breakwater is composed of piles and horizontal porous plates that was devised for the optimized blockage effects and wave energy dissipations. This system provides outstanding performances as wave barrier and added advantages such as a rapid installation, an easy relocation, a perfect water circulation for the stagnation of pollutions in sheltered regions. The present experimental study focuses on the performance evaluations of the proposed system in wind wave conditions as a wave dissipator and reflector. The reflection, transmission, and energy dissipation of the random waves has been discussed in detail based on a newly proposed relation between wave steepness and a plate width normalized by wave length that are major factors affecting the wave transmission.

Betaine Effects on Morphology, Proliferation, and p53-induced Apoptosis of HeLa Cervical Carcinoma Cells in Vitro

  • Guo, Yu;Xu, Li-Sha;Zhang, Ding;Liao, Ya-Ping;Wang, Hai-ping;Lan, Zhi-Hui;Guan, Wei-Jun;Liu, Chang-Qing
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.8
    • /
    • pp.3195-3201
    • /
    • 2015
  • Objectives: To investigate the effects of betaine on HeLa cell growth and apoptosis and molecular mechanisms. Materials and Methods: Concentrations of 0.1, 1.0, 5.0, 20.0, 100.0 mg/ml of betaine were used to evaluate the anticancer efficacy for HeLa cells respectively, and MCF-10A was also detected as a normal diploid cell control. Results: We found that proliferation of HeLa cells was inhibited significantly upon exposure to increasing betaine levels with the MTT test (p<0.05). The percentage of S phase cells in the low dose groups (<5mg/ml) were distinctly higher than in high dose groups, and the rates of Sub-G1 phase were the opposite (p<0.01); A high concentration of betaine (>5.0mg/ml) significantly promoted the apoptosis of HeLa cells (p<0.01). SOD activities of the low dose groups were slightly higher than the control group (p<0.05) and there were obvious synchronicity and correlation among the expression of promoting apoptosis genes Bax, P53, Caspase 3 and apoptosis suppression gene Bcl-2. In response to an apoptosis-inducing stimulus, p53 and cyclin D1 could be activated with blockage of the cell cycle at G1/S or S/G2 checkpoints. Conclusions: Our data showed that betaine could promote HeLa cells proliferation in vitro at low concentrations. In contrast, high concentrations could significantly inhibit cell growth and migration, and induce apoptosis of HeLa cells through caspase 3 signaling and further promoted necrosis. This might imply that betaine exhibits tumoricidal effects and acts as a biological response modifier in cancer treatment by inducing apoptosis and cell cycle arrest in a dose and time-dependent manner.