• Title/Summary/Keyword: Group Flow

Search Result 2,202, Processing Time 0.03 seconds

Selective iNOS Inhibition Attenuates Skeletal Muscle Reperfusion Injury (선택적 iNOS 억제에 의한 골격근 재관류 손상의 감소)

  • Park, Jong-Woong;Lee, Kwang-Suk;Kim, Sung-Kon;Park, Jung-Ho;Wang, Joon-Ho;Jeon, Woo-Joo;Lee, Jeong-Il
    • Archives of Reconstructive Microsurgery
    • /
    • v.15 no.1
    • /
    • pp.1-9
    • /
    • 2006
  • The purpose of this study is to determine the effects of selective inducible nitric oxide synthase (iNOS) inhibitor N-[3-aminomethyl]benzyl]acetamidine (l400W) on the reperfused cremaster muscle. The extracellular superoxide dismutase knockout ($EC-SOD^{-/-}$) mice was used to make the experimental window for ischemia-reperfusion injury. The muscle was exposed to 4.5 h of ischemia followed by 90 min of reperfusion and the mice received either 3 mg/kg of 1400W or the same amount of phosphate buffered saline (PBS) subcutaneously at 10 min before the start of reperfusion. The results showed that 1400W treatment markedly improved the recovery of the vessel diameter and blood flow in the reperfused cremaster muscle compared to that of PBS group. Histological examination showed reduced edema in the interstitium and muscle fiber, and reduced nitrotyrosine formation (a marker of total peroxinitrite ($ONOO^-$) in 1400W-treated muscle compared to PBS. Our results suggest that iNOS and $ONOO^-$ products are involved in skeletal muscle I/R injury. Reduced I/R injury by using selective inhibition of iNOS is perhaps via limiting cytotoxic $ONOO^-$ generation, a reaction product of nitric oxide (NO) and superoxide anion ($O_2^-$). Thus, inhibition of iNOS appears to be a good treatment strategy in reducing clinical I/R injury.

  • PDF

A Study of the Guided Wave Propagation in the Water Supplying Pipes with Scale (스케일이 있는 급수관내의 유도초음파의 전파 특성에 관한 연구)

  • Song, Sung-Jin;Lee, Dong-Hoon;Lee, Hyun-Dong;Bae, Cheol-Ho;Park, Jung-Hoon;Kim, Young-H.
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.23 no.1
    • /
    • pp.1-6
    • /
    • 2003
  • Since the scale in pipes reduces the flow rate, a quantitative evaluation of the scale is essential for the proper maintenance of pipes. Guided waves were employed to estimate the amount of scale in water supplying pipes. Using variable angle wedge, several modes of guided waves wire generated and their propagation charcteristics along the pipes with stale were analyzed. It was experimentally observed that the amplitude of F(M,2) modes at $f{\times}d=1.5MHz\;mm$ decreased significantly with increasing amount of scale. The present study showed that F(M,2) modes were optima) to evaluate the scale in water supplying pipes.

Numerical Investigation of Sunroof Buffeting for Hyundai Simplified Model (HSM의 썬루프 버페팅 수치해석)

  • Khondge, Ashok;Lee, Myunghoon
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.24 no.3
    • /
    • pp.180-188
    • /
    • 2014
  • Hyundai Motor Group(HMG) carried out experimental investigation of sunroof buffeting phenomena on a simplified car model called Hyundai simplified model(HSM). HMG invited participation from commercial CFD vendors to perform numerical investigation of sunroof buffeting for HSM model with a goal to determine whether CFD can predict sunroof buffeting behavior to sufficient accuracy. ANSYS Korea participated in this investigation and performed numerical simulations of sunroof buffeting for HSM using ANSYS fluent, the general purpose CFD code. First, a flow field validation is performed using closed sunroof HSM model for 60 km/h wind speed. The velocity profiles at three locations on the top surface of HSM model are predicted and compared with experimental measurement. Then, numerical simulations for buffeting are performed over range of wind speeds, using advanced scale resolving turbulence model in the form of detached eddy simulation (DES). Buffeting frequency and buffeting level are predicted in simulation and compared with experimental measurement. With reference to comparison between experimental measurements with CFD predictions of buffeting frequency and level, conclusion are drawn about predictive capabilities of CFD for real vehicle development.

Effects of Sokmyong-tang on Ferric Chloride-induced Carotid Injury and Thrombosis in a Rat Model (경동맥 손상 및 혈전을 유발한 동물 모델에서 속명탕(續命湯)의 효능 검증)

  • Heo, Eun Jung;Lee, In Sun;Kang, Hyung Won;Jeon, Won Kyung
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.26 no.5
    • /
    • pp.732-737
    • /
    • 2012
  • The aim of this study is examine the protection effect for artery and antithrombotic effect of Sokmyong-tang(SMT; xuming-tang) on carotid artery thrombosis in a rat model. Thirty minutes before $FeCl_3$ treatment, SD rats were intraperitoneal injected with SMT. We tested the effects of SMT on time to occlusion (TTO) in thrombosis model by induced $FeCl_3$ using the laser Doppler flow meter and accessed thrombus weight (TW) inhibition and measured collagen fibers in the vessel after injury using Masson's trichrome stain. SMT(100 mg/kg, i.p.) showed significantly delayed TTO ($13.17{\pm}1.33$ min, P < 0.001) compared to vehicle control group ($8.63{\pm}0.92$ min) and inhibiting effect on TW with $0.72{\pm}0.02$ mg/mm (P < 0.05). In addition, SMT prevented collagen fibres damage in injured vessel ($22.24{\pm}4.48%$, P < 0.001). These results provide experimental evidence for SMT can be used to prevent vascular injury and thrombosis such as hypertension, arteriosclerosis, and so on.

Inotodiol Inhabits Proliferation and Induces Apoptosis through Modulating Expression of cyclinE, p27, bcl-2, and bax in Human Cervical Cancer HeLa Cells

  • Zhao, Li-Wei;Zhong, Xiu-Hong;Yang, Shu-Yan;Zhang, Yi-Zhong;Yang, Ning-Jiang
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.7
    • /
    • pp.3195-3199
    • /
    • 2014
  • Inonotus obliquus is a medicinal mushroom that has been used as an effective agent to treat various diseases such as diabetes, tuberculosis and cancer. Inotodiol, an included triterpenoid shows significant anti-tumor effect. However, the mechanisms have not been well documented. In this study, we aimed to explore the effect of inotodiol on proliferation and apoptosis in human cervical cancer HeLa cells and investigated the underlying molecular mechanisms. HeLa cells were treated with different concentrations of inotodiol. The MTT assay was used to evaluate cell proliferating ability, flow cytometry (FCM) was employed for cell cycle analysis and cell apoptosis, while expression of cyclinE, p27, bcl-2 and bax was detected by immunocytochemistry. Proliferation of HeLa cells was inhibited by inotodiolin a dose-dependent manner at 24h (r=0.9999, p<0.01). A sub-$G_1$ peak (apoptotic cells) of HeLa cells was detected after treatment and the apoptosis rate with the concentration and longer incubation time (r=1.0, p<0.01), while the percentage of cells in S phase and $G_2$/M phase decreased significantly. Immunocytochemistry assay showed that the expression of cyclin E and bcl-2 in the treated cells significantly decreased, while the expression of p27 and bax obviously increased, compared with the control group (p<0.05). The results of our research indicate that inotodiol isolated from Inonotus obliquus inhibited the proliferation of HeLa cells and induced apoptosis in vitro. The mechanisms may be related to promoting apoptosis through increasing the expression of bax and cutting bcl-2 and affecting the cell cycle by down-regulation the expression of cyclin E and up-regulation of p27. The results further indicate the potential value of inotodiol for treatment of human cervical cancer.

New Method for Estimating Gas Interchangeability for 13A Gas Appliances (13A 가스기기 새 가스호환성 판정법)

  • Ha, Young-Cheol;Park, Seo-Jong;Park, Won-Sic;Choi, Kyoung-Seok;Lee, Chang-Eon
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.35 no.9
    • /
    • pp.961-967
    • /
    • 2011
  • The objective of this study was to develop a new method for estimating gas interchangeability for 13A gas appliances. The three basic principles for the development of this method are as follows: 1) to derive the secondary interchangeability factor that represents the effect of gas composition, in addition to the major interchangeability factor, i.e., Wobbe index; 2) to test every type of and each maker's domestic gas appliances that are widely used in our country, particularly including premixed gas appliances; and 3) to develop a simple estimation method. On the basis of these principles, thirty representative gas appliances were tested, and as a result, a simple two-dimensional interchangeability diagram consisting of Wobbe index and relative density was developed. Unlike conventional methods for estimating interchangeability, this method can be applied to premixed gas appliances, which have a narrow stable flame range, and the interchangeability range of this method then becomes narrower than that of the conventional methods.

Long Term Feeding Effects of Dietary Dehulled Soybean Meal as a Fish Meal Replacer in Growing Olive Flounder Paralichthys olivaceus

  • Kim, Young Chul;Yoo, Gwang Yeol;Wang, Xiaojie;Lee, Seunghyung;Shin, In Soo;Bai, Sungchul C.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.21 no.6
    • /
    • pp.868-872
    • /
    • 2008
  • This experiment was conducted to evaluate the long term effects of dehulled soybean meal (DHSM) as fish meal (FM) replacer in the diet for olive flounder, Paralichthys olivaceus, for 42 wk at a commercial fish farm. The four experimental diets were MP (moist pellet based on raw fish), $DHSM_0$ (fish meal based dry pellet), $DHSM_{30}$ (30% fish meal was replaced by DHSM) and COMD (commercial dry pellet). Fish were fed one of the four diets containing 50% crude protein and 16.7 kJ available energy/kg diet for 42 wk. Fish averaging $3.20{\pm}0.04g$ ($mean{\pm}SD$) were initially distributed to each tank as a group of 6,000 fish reared in a flow-through system. At the end of the experiment, average body weight of fish was $315{\pm}9.3g$ ($mean{\pm}SD$) ). Weight gain (WG) and feed efficiency (FE) of fish fed MP, DHSM0 and DHSM30 showed no significant difference among the diet treatments. However, WG and FE of fish fed MP were significantly higher than those of fish fed COMD (p<0.05). Specific growth rate (SGR), protein efficiency ratio (PER) and survival of fish fed all diets were not significantly different among the dietary treatments. Therefore, these results indicate that DHSM could replace up to 30% white fish meal with amino acid supplementation in olive flounder diets for long-term feeding practice at the commercial farm.

Implementation of Regional Cerebral Blood Volume Map Using Perfusion Magnetic Resonance Image Process Algorithm (관류자기공명 영상처리 알고리즘을 이용한 대뇌 혈류량 맵의 구현)

  • Park Byung-Rae
    • The Journal of the Korea Contents Association
    • /
    • v.5 no.5
    • /
    • pp.296-304
    • /
    • 2005
  • Quantitative analysis compare to dynamic characteristic change of the regional cerebral blood volume(rCBV) after development of cerebral fat embolism in cats using perfusion magnetic resonance(MR) Imaging. Twenty cats were used. Linoleic acid (n=11) were injected into the internal carotid artery using microcatheter through the transfemoral approach. Polyvinyl alcohol (Ivalon) (n=9) was injected as a control group. Perfusion MR images were obtained at 30 minutes and 2 hours after embolization, based on T2 and diffusion-weighted images. The data was time-to-signal intensity curve and ${\Delta}R_2^*$ curve were obtained continuously with the aid of home-maid image process algorithm and IDL(interactive data Banguage, USA) softwares. The ratios of rCBV increased significantly at 2 hours compared with those of 30 minutes (P<0.005). In conclusion, cerebral blood flow decreased in cerebral fat embolism immediately after embolization and recovered remarkably in time course. It is thought that clinically informations to dynamic characteristic change of the cerebral hemodynamics to the early finding in cerebral infarction by diffusion weighted imaging(DWI) and perfusion weighted imaging(PWI).

  • PDF

The Use of Salivary Gland Scintigraphy for Diagnosis of Primary Sjögren Syndrome and Thyroid Disease in Patients with Dry Mouth

  • Park, Keun Jeong;Kim, Bok Eum;Lee, Jung Eun;Park, YounJung;Kwon, Jeong-Seung;Ahn, Hyung-Joon;Choi, Jong-Hoon
    • Journal of Oral Medicine and Pain
    • /
    • v.44 no.4
    • /
    • pp.179-182
    • /
    • 2019
  • Sjögren syndrome (SS) is a chronic autoimmune disease characterized by dryness of the mouth and eyes due to lymphocytic infiltration of the exocrine glands. In American European Consensus Group (AECG) criteria, abnormal salivary gland scintigraphy (SGS) result is one of the objective signs of SS and it has been proposed as a valid and non-invasive alternative approach to functional evaluation of salivary gland, especially in the case when unstimulated whole salivary flow is more than 1.5 mL in 15 minutes or other AECG criteria is unmet. Patients with SS are more likely to have the thyroid disease (TD), but this association remains controversial. We present a case of the use of SGS for diagnosis of primary SS and TD in patients with dry mouth and burning sensation of tongue. Through this case, we suggest the usefulness of salivary scintigraphy for screening TD in addition to diagnosis of SS.

Effect of AC Electric Fields on Counterflow Diffusion Flame of Methane (메탄의 대향류 확산화염에 대한 AC 전기장의 영향)

  • Choi, Byung-Chul;Kim, Hyung-Kuk;Chung, Suk-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.36 no.8
    • /
    • pp.849-855
    • /
    • 2012
  • The effect of electric fields on the response of diffusion flames in a counterflow has been investigated experimentally by varying the AC voltage and frequency. The result showed that the flame was stationary with high AC frequency above the threshold frequency, and it increased with the applied voltage and then leveled off at 35 Hz. Below the threshold frequency, however, the flame oscillated with a frequency that was synchronized with the applied AC frequency. This oscillation can be attributed to the ionic wind effect due to the generation of bulk flow, which arises from the momentum transfer by molecular collisions between neutral molecules and ions, where the ions in the reaction zone were accelerated by the Lorentz force.