• Title/Summary/Keyword: pi

Search Result 7,039, Processing Time 0.042 seconds

Changes in the $Ca^{2+}-,\;Mg^{2+}-dependent$ Adenosine Triphosphatase Activity and Ultrastructure of Marine Fishes by Partial Freezing -I. Denaturation of Yellowtail Myofibrillar ATPase During Cold Storage- (해산어의 부분동결에 의한 $Ca^{2+}-,\;Mg^{2+}-dependent$ Adenosine Triphosphatase 활성 및 근섬유의 미세구조의 변화 -I. 저온저장에 의한 방어 근원섬유 단백질의 변성-)

  • Choi, Kyoung-Ho;Park, Chan-Sung
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.18 no.1
    • /
    • pp.123-130
    • /
    • 1989
  • Myofibrillar protein(myofibil) was prepared from Yellowtail fish (Seriola quinqueradiata), and then, it was stored at $0^{\circ}C$(ice-cooling), $-3.5^{\circ}C$(partial freezing) and $-20^{\circ}C$(freezing). Another myofibrils were prepared from the fish stored with ice-cooling, partial freezing and freezing for a week as the maximum. Denaturation of muscle protein during the storage was investigated by the measurement of $Ca^{2+}-$ and $Mg^{2+}-ATPase$ activity. Specific activity of $Ca^{2+}-\;and\;Mg^{2+}-ATPase$ associated with Yellowtail myofibrils was 0.155 and $0.149\;{\mu}\;mole$ Pi/min/mg of protein, respectively, before storgae. ATPase activity of myofibils did not show any significant difference between $0^{\circ}C$ and $-3.5^{\circ}C$ whereas it was decreased faster at $-20^{\circ}C$ than at $0^{\circ}C$ or $-3.5^{\circ}C$. ATPase activity of myofibirls extracted from the fish stored for a week was 1.2-1.8 times higher than myofibils stored with ice-cooling or partial freezing while it was 2.5-3 times higher than that with freezing. Apparent denaturation constant of $Ca^{2+}-ATPase$ of myofibrils was between 0.48-0.65, and it was 2-3 times higher than that of $Mg^{2+}-ATPase$. The constant of myofibrils extracted from the fish did not show significant difference between $Ca^{2+}-\;and\;Mg^{2+}-ATPase$.

  • PDF

Ginsenoside Rg3-enriched red ginseng extract inhibits platelet activation and in vivo thrombus formation

  • Jeong, Dahye;Irfan, Muhammad;Kim, Sung-Dae;Kim, Suk;Oh, Jun-Hwan;Park, Chae-Kyu;Kim, Hyun-Kyoung;Rhee, Man Hee
    • Journal of Ginseng Research
    • /
    • v.41 no.4
    • /
    • pp.548-555
    • /
    • 2017
  • Background: Korean Red Ginseng has been used for several decades to treat many diseases, enhancing both immunity and physical strength. Previous studies have documented the therapeutic effects of ginseng, including its anticancer, antiaging, and anti-inflammatory activities. These activities are mediated by ginsenosides present in the ginseng plant. Ginsenoside Rg3, an effective compound from red ginseng, has been shown to have antiplatelet activity in addition to its anticancer and anti-inflammatory activities. Platelets are important for both primary hemostasis and the repair of the vessels after injury; however, they also play a crucial role in the development of acute coronary diseases. We prepared ginsenoside Rg3-enriched red ginseng extract (Rg3-RGE) to examine its role in platelet physiology. Methods: To examine the effect of Rg3-RGE on platelet activation in vitro, platelet aggregation, granule secretion, intracellular calcium ($[Ca^{2+}]_i$) mobilization, flow cytometry, and immunoblot analysis were carried out using rat platelets. To examine the effect of Rg3-RGE on platelet activation in vivo, a collagen plus epinephrine-induced acute pulmonary thromboembolism mouse model was used. Results: We found that Rg3-RGE significantly inhibited collagen-induced platelet aggregation and $[Ca^{2+}]_i$ mobilization in a dose-dependent manner in addition to reducing ATP release from collagen-stimulated platelets. Furthermore, using immunoblot analysis, we found that Rg3-RGE markedly suppressed mitogen-activated protein kinase phosphorylation (i.e., extracellular stimuli-responsive kinase, Jun N-terminal kinase, p38) as well as the PI3K (phosphatidylinositol 3 kinase)/Akt pathway. Moreover, Rg3-RGE effectively reduced collagen plus epinephrine-induced mortality in mice. Conclusion: These data suggest that ginsenoside Rg3-RGE could be potentially be used as an antiplatelet therapeutic agent against platelet-mediated cardiovascular disorders.

Short Heterodimer Partner as a Regulator in OxLDL-induced Signaling Pathway

  • Kimpak, Young-Mi
    • Proceedings of the PSK Conference
    • /
    • 2001.10a
    • /
    • pp.109-113
    • /
    • 2001
  • Oxidized low-density lipoprotein (oxLDL) has been shown to modulate transactivations by the peroxisome proliferator activated receptor (PPAR)$\gamma$ and nuclear factor-kappa B (NF$\kappa$B). In this study, the oxLDL signaling pathways involved with the NF$\kappa$B transactivation were investigated by utilizing a reporter construct driven by three upstream NF$\kappa$B binding sites, and various pharmacological inhibitors. OxLDL and its constituent lysophophatidylcholine (lysoPC) induced a rapid and transient increase of intracellular calcium and stimulated the NF-KB transactivation in resting RAW264.7 macrophage cells in an oxidation-dependent manner. The NF$\kappa$B activation by oxLDL or lysoPC was inhibited by protein kinase C inhibitors or an intracellular calcium chelator. Tyrosine kinase or PI3 kinase inhibitors did not block the NF$\kappa$B transactivation. Furthermore, the oxLDL-induced NF$\kappa$B activity was abolished by the PPAR$\gamma$ ligands. When the endocytosis of oxLDL was blocked by cytochalasin B, the NF$\kappa$B transactivation by oxLDL was synergistically increased, while PPAR transactivation was blocked. These results suggest that oxLDL activates NF-$\kappa$B in resting macrophages via protein kinase C- and/or calcium-dependent pathways, which does not involve the endocytic processing of oxLDL. The endocytosis-dependent PPAR$\gamma$ activation by oxLDL may function as an inactivation route of the oxLDL induced NF$\kappa$B signal. Short heterodimer partner (SHP), specifically expressed in liver and a limited number of other tissues, is an unusual orphan nuclear receptor that lacks the conventional DNA-binding domain. In this work, we found that SHP expression is abundant in murine macrophage cell line RAW 264.7 but suppressed by oxLDL and its constituent I3-HODE, a ligand for peroxisome proliferator-activated receptor y. Furthermore, SHP acted as a transcription coactivator of nuclear factor-$\kappa$B (NF$\kappa$B) and was essential for the previously described NF$\kappa$B transactivation by lysoPC, one of the oxLDL constituents. Accordingly, NF$\kappa$B, transcriptionally active in the beginning, became progressively inert in oxLDL-treated RAW 264.7 cells, as oxLDL decreased the SHP expression. Thus, SHP appears to be an important modulatory component to regulate the transcriptional activities of NF$\kappa$B in oxLDL-treated, resting macrophage cells.

  • PDF

In vivo Pharmacokinetics, Activation of MAPK Signaling and Induction of Phase II/III Drug Metabolizing Enzymes/Transporters by Cancer Chemopreventive Compound BHA in the Mice

  • Hu, Rong;Shen, Guoxiang;Yerramilli, Usha Rao;Lin, Wen;Xu, Changjiang;Nair, Sujit;Kong, Ah-Ng Tony
    • Archives of Pharmacal Research
    • /
    • v.29 no.10
    • /
    • pp.911-920
    • /
    • 2006
  • Phenolic antioxidant butylated hydroxyanisole (BHA) is a commonly used food preservative with broad biological activities, including protection against chemical-induced carcinogenesis, acute toxicity of chemicals, modulation of macromolecule synthesis and immune response, induction of phase II detoxifying enzymes, as well as its undesirable potential tumor-promoting activities. Understanding the molecular basis underlying these diverse biological actions of BHA is thus of great importance. Here we studied the pharmacokinetics, activation of signaling kinases and induction of phase II/III drug metabolizing enzymes/transporter gene expression by BHA in the mice. The peak plasma concentration of BHA achieved in our current study after oral administration of 200 mg/kg BHA was around $10\;{\mu}M$. This in vivo concentration might offer some insights for the many in vitro cell culture studies on signal transduction and induction of phase II genes using similar concentrations. The oral bioavailability (F) of BHA was about 43% in the mice. In the mouse liver, BHA induced the expression of phase II genes including NQO-1, HO-1, ${\gamma}-GCS$, GST-pi and UGT 1A6, as well as some of the phase III transporter genes, such as MRP1 and Slco1b2. In addition, BHA activated distinct mitogen-activated protein kinases (MAPKs), c-Jun N-terminal kinase (JNK), extracellular signal-regulated protein kinase (ERK), as well as p38, suggesting that the MAPK pathways may play an important role in early signaling events leading to the regulation of gene expression including phase II drug metabolizing and some phase III drug transporter genes. This is the first study to demonstrate the in vivo pharmacokinetics of BHA, the in vivo activation of MAPK signaling proteins, as well as the in vivo induction of Phase II/III drug metabolizing enzymes/transporters in the mouse livers.

Multidimensional Factors Influencing Burnout in Intensive Care Unit Nurses (다차원적 요인이 중환자실 간호사의 소진에 미치는 영향)

  • Kim, Se Ra;Jeon, Mi-Kyeong;Hwang, Jin Hee;Choi, Ae Ran;Kim, In Sook;Pyon, Mi Kyoung;Moon, Kyoung Eun;Kim, Mun Hee;Shin, Na Ra;Lee, Soon Haeng
    • Journal of Korean Clinical Nursing Research
    • /
    • v.23 no.1
    • /
    • pp.9-19
    • /
    • 2017
  • Purpose: This study aimed to identify multidimensional factors influencing burnout in intensive care unit(ICU) nurses. Methods: A descriptive cross-sectional design was used. Data were collected during February 2016 from a convenience sample of 222 tertiary hospital ICU nurses and analyzed using t-test, ANOVA, correlation analysis, and multiple regression analysis. Results: Burnout correlated positively with compassion fatigue (CF)(r=.37, p<.001), and negatively with compassion satisfaction (CS)(r=-.66, p<.001). The regression model explained 57% of the variance in burnout. For individual characteristics in the model, perceived health status (${\beta}=-.27$, p<.001) and gender (${\beta}=.14$, p=.028) were the most influential factors for ICU nurses' burnout. In the model with added work-related characteristics, nursing environment (${\beta}=-.22$, p=.001), perceived health status (${\beta}= -.20$, p=.001), and satisfaction with department (${\beta}=-.19$, p=.007) were the most influential factors. Finally, for the model with psychological characteristics added, CS (${\beta}=-.56$, p<.001) and CF (${\beta}=.35$, p<.001) were the most influential factors. Conclusion: Results reveal that most ICU nurses have a moderate level of CF and a moderate to high level of CS and burnout, and that individual, work-related and psychological factors are relevant in ICU nurses' burnout. Programs or interventions to reduce burnout should be developed taking into account these multidimensional factors.

Benzothiazole Substituted Benzocrown Ether-Based Potassium Ion-Selective Membrane Electrodes (벤조티아졸기를 갖는 벤조크라운에테르를 전극물질로 사용한 $K^+$ 이온선택성 막전극)

  • Hong, Uk Sun;Kwon, Hye Kyong;Cha, Geun Sig;Nam, Hakhyun;Chang, Seung Hyun;Chung, Kwang Bo
    • Journal of the Korean Chemical Society
    • /
    • v.39 no.9
    • /
    • pp.698-704
    • /
    • 1995
  • The ion-selective membrane fabricated with 33 wt% PVC, 66 wt% o-NPOE and 1 wt% 4'-benzothiazolylbenzo-15-crown-5 (TB15C5) as a neutral carrier exhibited an enhanced selectivity to potassium ion over sodium ion compared to those prepared with other 15-crown-5 or 18-crown-6 derivatives. The potentiometric properties (response slope, selectivity, detection limits and lifetime) of TB15C5-based ISE membranes along with those based on valinomycin, benzo-15-crown-5 (B15C5), 4'-aminobenzo-15-crouwn-5 (AB15C5), benzo-18-crown-6 (B18C6), dibenzo-18-crown-6 (DB18C6) and bis[(benzo-15-crown-5)-4'-ylmethyl]pimelate (PI-Ⅱ) ionophores were carefully examined under the same experimental conditions. The enhanced selectivity of TB15C5-based membrane to potassium is explained in terms of the effect of the benzothiazol functional group and the distribution coefficients of metal ions.

  • PDF

Damage Study on the Mechanical Fastening in Laminated Composites (복합적층판(復合積層板)의 기계적(機械的) 체결부(締結部)에 관한 파손연구(破損硏究))

  • Kwan-Hyung,Song
    • Bulletin of the Society of Naval Architects of Korea
    • /
    • v.27 no.4
    • /
    • pp.58-66
    • /
    • 1990
  • A series of test was performed measuring the failure strength and failure mode of Gr/Pi, $[0^{\circ}/45^{\circ}/90^{\circ}/-45^{\circ}]_s$ laminate containing a single pin loaded hole. The finite element method is applied to calculate the stress distribution in the laminates, then the failure load and the failure mode were predicted by means of the characteristic length. 12 different geometric variations were developed to analyze the effects of the ratio of specimen width to hole diameter (W/d) and ratio of edge distance to hole diameter (L/d). X-Ray of NDE methods were utilized in finding out the initial defects, damage and the fracture mechanism, and SEM(Scanning Electron Microscopes) was used the evaluation of the fracture mechanism and crack propagation around hole under tension pin loading. $[0^{\circ}/45^{\circ}/90^{\circ}/-45^{\circ}]_s$ laminate are found to be most sensitive to W/d but not so influenced by L/d. The failure mode and tensile strength predicted by the model show agreement with experiment data for pin loading bolted jointed test except range of $L/d{\leqq}3$.

  • PDF

Joint Design and Strength Evaluation of Composite Air Spoiler for Ship (선박용 복합재 에어 스포일러의 체결부 설계 및 강도 평가)

  • Pi, June-Woo;Jeon, Sang-Bae;Lee, Guen-Ho;Jo, Young-Dae;Choi, Jin-Ho;Kweon, Jin-Hwe
    • Composites Research
    • /
    • v.28 no.4
    • /
    • pp.219-225
    • /
    • 2015
  • Air spoiler, which can reduce the drag during operation, can be considered as a possible means to reduce carbon dioxide emission and to increase fuel efficiency. In this study, a composite air spoiler was designed and tested by static and repeated loads. The Green Water Pressure of 0.1 MPa a ship experiences during operation was perpendicularly applied to the air spoiler. Air spoiler was manufactured with sandwich panel which has glass fabric face and balsa core. Multiple sandwich panels were assembled to steel frame by bolt joint. The joint was designed to have bearing failure and examined by static and fatigue tests. Tests showed that the designed joint has enough margin of safety to endure joint failure. The developed sandwich panel to air spoiler is planned to be applied to a large scale commercial ship.

The Comparative Study between Leg Length Analysis and X-ray on Diagnosis of Pelvic Malpositions - according to Positions and Valuation Bases - (기능성 족지장단분석과 X-ray의 골반변위 진단의 비교 연구 - X-ray 촬영 자세 및 평가 기준에 따라 -)

  • Lee, Jung-Min;Koog, Gil-Ho;Choi, Bo-Mi;Jeong, Hyun-A;Hong, Seo-Young
    • The Journal of Churna Manual Medicine for Spine and Nerves
    • /
    • v.5 no.2
    • /
    • pp.169-180
    • /
    • 2010
  • Objectives: This study was carried out to investigate the relationship of leg length analysis and X-ray finding according to positions and valuation bases on diagnosis of pelvic malpositions. Methods: Twenty-two people who get $33.09{\pm}10.73$ as average were evaluated by leg length analysis and X-ray findings. After measuring innominate measurement(IM), femur head line. distance between S2 and posterior superior iliac spine(PSIS). ilium shadow measurement(ISM), major axis of obturator foramen(MaF), minor axis of obturator foramen(MiF) and distance between off centering measurement and symphysis pubis, those were analyzed. Results: 1. In assessment of posterior rotation malposition ilium(PI), it was showed the best coincidence between leg length analysis and X-ray analyzed by 1M in supine position(11 cases, 50.5%). 2. In assessment of inflare, coincidence index between leg length analysis and X-ray were not good($4.00{\pm}3.03$ cases, $18.15{\pm}13.82%$). And leg length analysis were not sensitive. 3. On the whole, coincidence index between leg length analysis and X-ray were not good(best: 1 case, 45.5%; worst: 11 cases, 50.0%). Conclusions: Results form this investigation showed the relationship of leg length analysis and X-ray according 10 positions and valuation bases on diagnosis of pelvic malpositions. This results are expected to contribute to establish method of assessment in diagnosis of pelvic malpositions.

  • PDF

The Far-ultraviolet Spectrum Study of Comet C/2001 Q4 (NEAT)

  • Lim, Yeo-Myeong;Min, Kyoung-Wook;Feldman, Paul D.;Han, Wanyong;Edelstein, Jerry
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.39 no.1
    • /
    • pp.68.1-68.1
    • /
    • 2014
  • We present the results of far-ultraviolet (FUV) observations of comet C/2001 Q4 (NEAT) obtained with Far-ultraviolet Imaging Spectrograph (FIMS) on board the Korean microsatellite STSAT-1, which operated at an altitude of 700 km in a sun-synchronous orbit. FIMS is a dual channel imaging spectrograph (S-channel 900-1150 ${\AA}$, L-channel 1350-1710 ${\AA}$, and ${\lambda}/{\Delta}{\lambda}$ ~ 550 for both channels) with large image fields of view (S-channel $4.0^{\circ}{\times}4.6^{\prime}$, L-channel $7.5^{\circ}{\times}4.3^{\prime}$, and angular resolution ~ $5-10^{\prime}$) optimized for the observation of diffuse emission of astrophysical radiation. Comet C/2001 Q4 (NEAT) were made in two campaigns during its perihelion approach between May 8 and 15, 2004. Based on the scanning mode observations in the wavelength band of 1400-1700 ${\AA}$, we have constructed an image of the comet with an angular size of $5^{\circ}{\times}5^{\circ}$, which corresponds to the central coma region. Several important fluorescence emission lines were detected including S I multiplets at 1429 and 1479 ${\AA}$, C I multiplets at 1561 and 1657 ${\AA}$, and the CO $A^1{\Pi}-X^1{\Sigma}^+$ Fourth Positive system; we have estimated the production rates of the corresponding species from the fluxes of these emission lines. The estimated production rate of CO was $Q_{CO}=(2.65{\pm}0.63){\times}10^{28}s^{-1}$, which is 6.2-7.4% of the water production rate and is consistent with earlier predictions. The average carbon production rate was estimated to be $Q_C={\sim}1.59{\times}10^{28}s^{-1}$, which is ~60% of the CO production rate. However, the observed carbon profile was steeper than that predicted using the two-component Haser model in the inner coma region, while it was consistent with the model in the outer region. The average sulfur production rate was $Q_S=(4.03{\pm}1.03){\times}10^{27}s^{-1}$, which corresponds to ~1% of the water production rate.

  • PDF