• Title/Summary/Keyword: alpha channel

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Differential role of endothelium in hawthorn fruit extract-induced relaxation of rat cerebral, coronary, carotid, and aorta

  • Chan, Hoi Yun;Chen, Zhen-Yu;Yao, Xiaoqiang;Lau, Chi-Wai;Zhang, ZeSeng;Ho, Walter Kwok Keung;Huang, Yu
    • Advances in Traditional Medicine
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    • 제2권2호
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    • pp.87-93
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    • 2002
  • The present study was aimed to examine the role of endothelium in the relaxant effect of hawthorn fruit extract of Crataegus pinnatifida in four different types of rat arteries, posterior cerebral communicating artery, right descending coronary artery, common carotid artery, and aorta. In $9,11-dideoxy-11{\alpha}$, $9{\alpha}-epoxy-methanoprostaglandin$ $F_{2{\alpha}}$ (U46619)-preconstricted arterial rings except for aorta, the extract produced endothelium-independent relaxations with similar potency. This relaxation was unaffected by pretreatment with $100\;{\mu}M\;N^G-nitro-L-arginine$ methylester (L-NAME, the nitric oxide synthase inhibitor), $3\;{\mu}M$ 1H-[l,2,4]oxadiazolo$[4,2-{\alpha}]$quinoxalin-1-one (ODQ, the guanylate cyclase inhibitor), or $10\;{\mu}M$ indomethacin (the cyclooxygenase inhibitor). Putative $K^+$ channel blockers (charybdotoxin plus apamin or glibenclamide) did not affect the extract-induced relaxation in cerebral or coronary artery rings. In contrast, in rat aortic rings the extract produced significantly smaller relaxant response in endothelium-denuded rings than that in endothelium-intact rings. Pretreatment with L-NAME or ODQ abolished the extractinduced endothelium-dependent aortic relaxation, whilst indomethacin $(3\;{\mu}M)$ had no effect. The present results indicate that hawthorn fruit extract possesses a vasorelaxing effect in cerebral, coronary and carotid arteries and this effect is independent of the presence of a functional endothelium. However, the extract-induced endothelium-dependent relaxation in rat aorta was mediated through endothelial nitric oxide and cyclic GMP-dependent mechanisms, suggesting that active components in the extract may act on endothelium to stimulate release of nitric oxide in large conduit arteries of the rats.

내관$(PC_6)$의 황련해독탕 약침이 EEG 변화에 미치는 효과 (The Effect of Hwangryunhaedoktang Herbal Acupuncture at the $PC_6$(Naegwan) on the EEG)

  • 김동석;이상룡
    • Korean Journal of Acupuncture
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    • 제21권3호
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    • pp.39-58
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    • 2004
  • Objectives : The aim of this study was to examine the effects of Hwangryunhaedoktang Herbal acupuncture at the PC6(Naegwan) on the EEC of normal human being by using power spectral analysis. Methods : EEC power spectrum exhibit site-specific and state-related differences in specific frequency bands. In this study, power spectrum was used as a measure of complexity. 32 channel EEC study was carried out in 11 subjects (11 males; age=27.8 years). Results : In ${\alpha}(alpha)$ band, the power values at T3, TT1, CP1, T5, Po2, O1, Oz channels(p<0.05) during the PC6-acupoint treatment were increased significantly. In ${\beta}(beta)$ band, the power values at TT1, CP1, T5, P3, Po2, O1, Oz channels(p<0.05) during the PC6-acupoint treatment were increased significantly. In ${\theta}(theta)$ band, the power values at T3, TT1, CP1, Po2, O1, Oz channels(p<0.05) during the PC6-acupoint treatment were increased significantly. In ${\delta}(delta)$ band, the power values at F4, T3, CP1, O1, Oz, O2 channels(p<0.05) during the PC6-acupoint treatment were increased significantly. Conclusions : This results suggest that Hwangryunhaedoktang Herbalacupuncture at the PC6 is significantly in ${\alpha}(alpha)$ band.

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Proteomic Analysis of Differentially Expressed Proteins in Bovine Endometrium with Endometritis

  • Choe, Chang-Yong;Park, Jeong-Won;Kim, Eun-Suk;Lee, Sung-Gyu;Park, Sun-Young;Lee, Jeong-Soon;Cho, Myung-Je;Kang, Kee-Ryeon;Han, Jae-Hee;Kang, Da-Won
    • The Korean Journal of Physiology and Pharmacology
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    • 제14권4호
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    • pp.205-212
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    • 2010
  • Endometritis is one of the primary reasons for reproductive failure. In order to investigate endometritis-associated marker proteins, proteomic analysis was performed on bovine endometrium with endometritis. In bovine endometritis, desmin, $\alpha$-actin-2, heat-shock protein (HSP) 27, peroxiredoxin-6, luteinizing hormone receptor isoform 1, collectin-43 precursor, deoxyribonuclease-I (DNase-I), and MHC class I heavy chain (MHC-Ih) were up-regulated. In contrast, transferrin, interleukin-2 precursor, hemoglobin $\beta$ subunit, and potassium channel tetramerisation domaincontaining 11 (KCTD11) were down-regulated in comparison to normal endometrium. The proteomic results were validated by semiquantitative-PCR and immunoblot analysis. The mRNA levels of desmin, transferrin, $\alpha$-actin-2, HSP27, KCTD11, and MHC-Ih were up-regulated by over 1.5-fold, and showed a pattern similar to their proteomic profiles. Desmin and $\alpha$-actin-2 protein showed positive correlations between proteomic analysis and immunoblot analysis. These results suggest that desmin and $\alpha$-actin-2 may play important roles in endometritis-related function, and could be useful markers for the diagnosis of bovine endometritis.

교행식생 영역을 갖는 개수로 흐름에서의 3차원 수치모의 (Three-Dimensional Numerical Simulations of Open-Channel Flows with Alternate Vegetated Zones)

  • 강형식;김규호;임동균
    • 대한토목학회논문집
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    • 제29권3B호
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    • pp.247-257
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    • 2009
  • 본 연구에서는 흐름방향으로 식생 영역이 교차적으로 식재된 교행식생 수로에서의 3차원 수치모의를 수행하였다. 지배방정식에서의 난류 폐합을 위해 ${\kappa}-{\varepsilon}$ 모형을 적용하였으며, 수치모형은 Olsen(2004)이 개발한 3차원 모형을 이용하였다. 먼저, 3차원 수치모형을 이용하여 하상의 일부가 식재된 부분 식생 수로를 수치모의 하고, 계산된 적분유속 및 레이놀즈응력을 기존의 실험 결과와 비교하였다. 그 결과 본 모형이 식생 수로에서의 평균 유속 분포를 매우 잘 예측하는 것으로 나타났다. 그러나 ${\kappa}-{\varepsilon}$ 모형이 등방성 모형이므로 식생과 비식생 영역의 경계면 부근에서 발생되는 운동량 교환 효과를 정확히 예측할 수 없는 것으로 나타났다. 한편, 주흐름방향으로 식생 영역이 교차적으로 존재하는 교행식생 수로를 수치모의 하고, 계산된 유속 분포를 기존의 실험 결과와 비교한 결과, 계산 유속과 실험 결과가 매우 잘 일치하는 것으로 나타났다. 또한 다양한 밀도에 따른 유속 벡터도를 계산한 결과, 식생밀도가 증가함에 따라 식생이 흐름 방향을 변화 시켜 점차 만곡수로와 유사한 형태의 유속 벡터도를 갖는 것으로 나타났으며, 식생 밀도 ${\alpha}$가 9.97%인 경우에는 식생 반대 측벽 영역에서 재순환 흐름이 형성되는 것으로 나타났다. 한편, 식생 밀도에 따른 단면 유속 분포도 및 편수위 변화를 살펴보았다.

기니픽 심장과 심근 세포에서 ${\alpha}_1-Adrenergic$ 자극에 의한 $Mg^{2+}$ 유리조절 (Regulation of $Mg^{2+}$ Release in Guinea Pig Heart and Isolated Ventricular Myocytes by ${\alpha}_1-Adrenergic$ Stimulation)

  • 강형섭;장성은;김진상
    • The Korean Journal of Physiology and Pharmacology
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    • 제1권6호
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    • pp.717-730
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    • 1997
  • $Mg^{2+}$ is the fourth most abundant cation in cellular organisms. Although the biological chemistry and the physiological roles of the magnesium ion were well known, the regulation of intracellular $Mg^{2+}$ in mammalian cells is not fully understood. More recently, however, the mechanism of $Mg^{2+}$ mobilization by hormonal stimulation has been investigated in hearts and in myocytes. In this work we have investigated the regulation mechanism responsible for the $Mg^{2+}$ mobilization induced by ${\alpha}1-adrenoceptor$ stimulation in perfused guinea pig hearts or isolated myocytes. The $Mg^{2+}$ content of the perfusate or the supernatant was measured by atomic absorbance spectrophotometry. The elimination of $Mg^{2+}$ in the medium increased the force of contraction of right ventricular papillary muscles. Phenylephrine also enhanced the force of contraction in the presence of $Mg^{2+}$-free medium. ${\alpha}1-Agonists$ such as phenylephrine were found to induce $Mg^{2+}$ efflux in both perfused hearts or myocytes. This was blocked by prazosin, a ${\alpha}1-adrenoceptor$ antagonist. $Mg^{2+}$ efflux by phenylephrine was amplified by $Na^+$ channel blockers, an increase in extracellular $Ca^{2+}$ or a decrease in extracellular $Na^+$. By contrast, the $Mg^{2+}$ influx was induced by verapamil, nifedipine, ryanodine, lidocaine or tetrodotoxin in perfused hearts, but not in myocytes. $W_7$, a $Ca^{2+}/calmodulin$ antagonist, completely blocked the pheylephrine-, A23187-, veratridine-, $Ca^{2+}-induced$ $Mg^{2+}$ efflux in perfused hearts or isolated myocytes. In addition, $Mg^{2+}$ efflux was induced by $W_7$ in myocytes but not in perfused heart. In conclusion, An increase in $Mg^{2+}$ efflux by ${\alpha}1-adrenoceptor$ stimulation in hearts can be through $IP_3$ and $Ca^{2+}-calmodulin$ dependent mechanism.

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돼지 난관협부 평활근의 운동성에 대한 acetylcholine, norepinephrine, histamine 및 prostaglandin F2α의 작용 (Actions of acetylcholine, norepinephrine, histamine and prostaglandin F2α on motility of pig oviductal isthmic smooth muscle)

  • 노규진;박상은;심철수;김주헌;최상용
    • 대한수의학회지
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    • 제34권3호
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    • pp.493-500
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    • 1994
  • The purpose of this study was to investigate the effects of neurotransmitters and the source of $Ca^{2+}$ in the effects of neurotransmitters on the motility of pig oviductal isthmic smooth muscle. The motility of the isolated smooth muscle was recorded by using physiological recording system. The results were summarized as follows; Acetylcholine, norepinephrine, histamine and prostaglandin $F_{2{\alpha}}(PGF_{2{\alpha}})$ caused the contraction and the contractile responses were increased in a dose-dependent manner from the concentration of $10^{-7}$ to $10^{-4}M$. The maximum contractility of acetylcholine, norepinephrine, histamine and $PGF_{2{\alpha}}$ was 65.99, 28.66, 83.99 and 47.33% of 100 mM K contraction, respectively. The contractile response induced by acetylcholine$(10^{-6}M)$ was completely blocked by the pretreatment with cholinergic receptor blocker, atropine$(10^{-6}M)$, the contractile response induced by norepinephrine$(10^{-5}M)$ was blocked by the pretreatment with ${\alpha}$-adrenergic receptor blocker, phentolamine$(10^{-6}M)$ but was not blocked and rather increased by the pretreatment with ${\beta}$-adrenergic receptor blocker. propranolol$(10^{-6}M)$, the contractile response induced by histamine$(10^{-6}M)$ was completely blocked by the pretreatment with $H_1$-histaminergic receptor blocker, pyrilamine$(10^{-6}M)$ but was increased by the pretreatment with $H_2$-histaminergic receptor blocker, cimetidine$(10^{-6}M)$. The contractile response induced by acetylcholine$(10^{-6}M)$, norepinephrine$(10^{-5}M)$ and histamine$(10^{-6}M)$ was weakly contracted response in $Ca^{2+}$-free medium, but the contractile response induced by $PGF_{2{\alpha}}(10^{-6}M)$ was disappeared. The contractile response induced by acetylcholine$(10^{-6}M)$, norepinephrine$(10^{-5}M)$ and histamine$(10^{-6}M)$ was powerfully depressed by the pretreatment with $Ca^{2+}$-channel blocker, verapamil$(10^{-5}M)$ but the contractile response induced by $PGF_{2{\alpha}}(10^{-6}M)$ was completely inhibited.

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Differential Effect of Bovine Serum Albumin on Ginsenoside Metabolite-Induced Inhibition of ${\alpha}3{\beta}4$ Nicotinic Acetylcholine Receptor Expressed in Xenopus Oocytes

  • Lee, Jun-Ho;Jeong, Sang-Min;Lee, Byung-Hwan;Kim, Dong-Hyun;Kim, Jong-Hoon;Kim, Jai-Il;Lee, Sang-Mok;Nah, Seung-Yeol
    • Archives of Pharmacal Research
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    • 제26권10호
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    • pp.868-873
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    • 2003
  • Ginsenosides, major active ingredients of Panax ginseng, that exhibit various pharmacological and physiological actions are transformed into compound K (CK) or M4 by intestinal microorganisms. CK is a metabolite derived from protopanaxadiol (PD) ginsenosides, whereas M4 is a metabolite derived from protopanaxatriol (PT) ginsenosides. Recent reports shows that ginsenosides might playa role as pro-drugs for these metabolites. In present study, we investigated the effect of bovine serum albumin (BSA), which is one of major binding proteins on various neurotransmitters, hormones, and other pharmacological agents, on ginsenoside $Rg_{2-}$, CK-, or M4-induced regulation of $\alpha3\beta4$ nicotinic acetylcholine (ACh) receptor channel activity expressed in Xenopus oocytes. In the absence of BSA, treatment of ACh elicited inward peak current ($I_{Ach}$) in oocytes expressing $\alpha3\beta4$ nicotinic ACh receptor. Co-treatment of ginsenoside $Rg_2$, CK, or M4 with ACh inhibited IAch in oocytes expressing $\alpha3\beta4$ nicotinic ACh receptor with reversible and dose-dependent manner. In the presence of 1% BSA, treatment of ACh still elicited $I_{Ach}$ in oocytes expressing $\alpha3\beta4$ nicotinic ACh receptor and co-treatment of ginsenoside $Rg_2$ or M4 but not CK with ACh inhibited $I_{Ach}$ in oocytes expressing $\alpha3\beta4$ nicotinic ACh receptor with reversible and dose-dependent manner. These results show that BSA interferes the action of CK rather than M4 on the inhibitory effect of $I_{Ach}$ in oocytes expressing $\alpha3\beta4$ nicotinic ACh receptor and further suggest that BSA exhibits a differential interaction on ginsenoside metabolites.

Effect of Neurosteroid Modulation on Global Ischaemia-Reperfusion-Induced Cerebral Injury in Mice

  • Grewal, Amarjot Kaur;Jaggi, Amteshwar Singh;Rana, Avtar Chand;Singh, Nirmal
    • The Korean Journal of Physiology and Pharmacology
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    • 제17권6호
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    • pp.485-491
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    • 2013
  • The present study was designed to investigate the putative effect of neurosteroid modulation on global ischaemia-reperfusion-induced cerebral injury in mice. Bilateral carotid artery occlusion followed by reperfusion, produced a significant rise in cerebral infarct size along with impairment of grip strength and motor coordination in Swiss albino mice. Administration of carbamazepine (16 mg/kg, i.p.) before global cerebral ischaemia significantly attenuated cerebral infarct size and improved the motor performance. However, administration of indomethacin (100 mg/kg, i.p.) attenuated the neuroprotective effect of carbamazepine. Mexiletine (50 mg/kg, i.p.) did not produce significant neuroprotective effect. It may be concluded that the neuroprotective effect of carbamazepine may be due to increase in synthesis of neurosteroids perhaps by activating enzyme ($3{\alpha}$ HSD) as indomethacin attenuated the neuroprotective effect of carbamazepine. The sodium channel blocking effect of carbamazepine may not be involved in neuroprotection as mexiletine, a sodium channel blocker, did not produce significant neuroprotective effect.

산화막과 질화막 위에 제작된 3D SONOS 다층 구조 플래시 메모리소자의 1/f 잡음 특성 분석 (The 1/f Noise Analysis of 3D SONOS Multi Layer Flash Memory Devices Fabricated on Nitride or Oxide Layer)

  • 이상율;오재섭;양승동;정광석;윤호진;김유미;이희덕;이가원
    • 한국전기전자재료학회논문지
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    • 제25권2호
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    • pp.85-90
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    • 2012
  • In this paper, we compared and analyzed 3D silicon-oxide-nitride-oxide-silicon (SONOS) multi layer flash memory devices fabricated on nitride or oxide layer, respectively. The device fabricated on nitride layer has inferior electrical properties than that fabricated on oxide layer. However, the device on nitride layer has faster program / erase speed (P/E speed) than that on the oxide layer, although having inferior electrical performance. Afterwards, to find out the reason why the device on nitride has faster P/E speed, 1/f noise analysis of both devices is investigated. From gate bias dependance, both devices follow the mobility fluctuation model which results from the lattice scattering and defects in the channel layer. In addition, the device on nitride with better memory characteristics has higher normalized drain current noise power spectral density ($S_{ID}/I^2_D$>), which means that it has more traps and defects in the channel layer. The apparent hooge's noise parameter (${\alpha}_{app}$) to represent the grain boundary trap density and the height of grain boundary potential barrier is considered. The device on nitride has higher ${\alpha}_{app}$ values, which can be explained due to more grain boundary traps. Therefore, the reason why the devices on nitride and oxide have a different P/E speed can be explained due to the trapping/de-trapping of free carriers into more grain boundary trap sites in channel layer.

128 채널 뇌파를 이용한 사이버멀미 평가법 개발 (Development of a Method of Cybersickness Evaluation with the Use of 128-Channel Electroencephalography)

  • 한동욱;이동현;지경하;안봉영;임현균
    • 감성과학
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    • 제22권3호
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    • pp.3-20
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    • 2019
  • 가상현실 기술이 발전하면서 다양한 영역에서 여러 목적으로 활용되고 있다. 하지만 사용자로부터 메스꺼움, 어지러움 등과 같은 멀미 증상에 대한 부작용도 함께 보고되고 있다. 이런 멀미 증상을 사이버멀미라고 말하며, 사용자에게 불편을 야기시켜 불쾌감과 스트레스와 같은 부정적 영향을 줄 수 있으며, 현재 사이버멀미의 발생 원인과 해결책에 관한 공식적인 표준이 없다. 본 연구에서는 이런 한계점을 극복하기 위해 정량적, 객관적 사이버멀미 평가법을 제안하였다. 10명의 20대 남성 대상으로 이동과 회전을 하는 가상현실을 경험하게 하면서 128채널의 뇌파를 측정하였다. 11개 영역에서 Delta와 Alpha 상대 파워를 계산하고, ROC curve를 통해 area under the ROC curve (AUC)가 가장 높은 값을 가지는 다중회귀모형을 도출하였다. 이렇게 도출한 다중회귀모형은 11개의 설명변수로 피험자가 응답한 사이버멀미의 정도와 비교하여 95.1 % (AUC = 0.951)의 정확성으로 사이버멀미를 구분하는 것이 가능함을 알 수 있었다. 이러한 결과를 정리하면 본 연구에서는 128 채널의 뇌파를 통해 멀미에 대한 객관적 반응을 확인하였으며, 뇌의 특정부위에서 반응이 있는 것으로 나타났다. 본 연구 결과와 분석법을 활용하면 추후 사이버멀미 관련 연구에 도움이 될 수 있을 것으로 기대된다.