• Title/Summary/Keyword: Whole-cell current

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External and Internal Morphological Standard of original plants and herbal states in Pogostemonis and Agastachis Herba (광곽향(廣藿香)과 토곽향(土藿香)의 외부(外部) 및 내부형태연구)

  • Kim, Hong-Jun;Choi, Jeong;Ju, Young-Sung
    • Korean Journal of Oriental Medicine
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    • v.12 no.2 s.17
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    • pp.75-83
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    • 2006
  • Pogostemonis and Agastachis Herba are the whole of Pogostemon cablin (BLANCO) BENTH or Agastache rugosa (FISCHER et MEYER) O. KUNTZE (family Labiatae) which is produced in all part of Korea and China. This drug is used for removing dampness by means of aromatics in oriental medicine. The standard formula of this drug is important from the viewpoint of the quality control. A characteristic discrimination of internal and external morphological standard in original plants and herbal states of Pogostemonis and Agastachis Herba are as follows. 1. The external characteristics: Pogostemon cablin has hairs and brown-like in stem, elliptical fruit. In the other hand, Agastache rugosa has no hairs and red-like in stem, obovatic trigone fruit. 2. The physical characteristics: Pogostemon cablin is gray in whole, has hairs in stem and numerous hairs of ash in leaf. In the other hand, Agastache rugosa is yellow-green in whole, has no hairs in stem. Specially the latter has deep-green colour and numerous hairs presenting mostly at lower epidermis in leaf. 3. The physical characteristics in currents: Pogostemon cablin is brown, has hairs and round-like stem. In the other hand, Agastache rugosa is green or yellow-green, has no hairs and tetragon in stem. 4. The internal characteristics: Pogostemon cablin has progressed spongy tissue in epidermal cell of leaf and many rank of epidermal cell in stem. In other hand, Agastache rugosa has 1 rank palisade tissue in leaf and few rank of epidermal cell in stem. In the external shape, it was possible that herbs were distinguished according to artificial classification and that same genus-degree of relatedness among herbs could be distinguished by more precise and active observation. In the shape of real herbs, I compared current herbs in market with original herbs which were just collected or were on the course of drying. In addition, it was possible that the internal shape could be identified by using microscope after butanol series. Though it was impossible to make distinction of herbs which are not current in my search contents, this search contents will be a standard for applying herbs in the future. An Additional standard establishment including physiochemical reaction and gene research is required in order to supplement the fault of this search.

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Torilin from Torilis japonica (Houtt.) DC. Blocks hKv1.5 Channel Current

  • Kwak, Yong-Geun;Kim, Dae-Keun;Ma, Tian-Ze;Park, Sun-Ah;Park, Hoon;Jung, Young-Hoon;Yoo, Dong-Jin;Eun, Jae-Soon
    • Archives of Pharmacal Research
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    • v.29 no.10
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    • pp.834-839
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    • 2006
  • Torilin was purified from Torilis japonica (Houtt.) DC., and its effects on a rapidly activating delayed rectifier $K^+$ channel (hKv1.5), cloned from human heart and stably expressed in Ltk cells, as well as the corresponding $K^+$ current (the ultrarapid delayed rectifier, $I_{KUR}$) were assessed in human atrial myocytes. Using the whole cell configuration of the patch-clamp technique, torilin was found to inhibit the hKv1.5 current in time and voltage-dependent manners, with an $IC_50$ value of $2.51{\pm}0.34\;{\mu}M$ at +60 mV. Torilin accelerated the inactivation kinetics of the hKv1.5 channel, and slowed the deactivation kinetics of the hKv1.5 current, resulting in a tail crossover phenomenon. Additionally, torilin inhibited the hKv1.5 current in a use dependent manner. These results strongly suggest that torilin is a type of open-channel blocker of the hKv1.5 channel.

The System Dynamics Model Development for Forecasting the Capacity of Renewables (신재생에너지 보급량 예측을 위한 시스템다이내믹스 모델 개발)

  • Kim, Hyun-Shil;Ko, Kyung-Ho;Ahn, Nam-Sung;Cho, Byung-Oke
    • Korean System Dynamics Review
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    • v.7 no.2
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    • pp.35-56
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    • 2006
  • Korea is implementing strong regulatory derives such as Feed in Tariff to provide incentives for renewable energy developers. But if the government is planning to increase the renewable capacity with only "Price policy" not considering the investors behavior in the competitive electricity market, the policy would be failed. It is necessary system thinking and simulation model analysis to decide government's incentive goal. This study is focusing on the assesment of the competitiveness of renewable energy with the current Feed in Tariff incentives compared to the traditional energy source, specially coal and gas. The simulation results show that the market penetration of renewable energy with the current Feed-in-Tariff level is about 60-70% of the government goal under condition that the solar energy and fuel cell are assumed to provide the whole capacity set in the governmental goal. If the contribution from solar and fuel cell is lower than planned, the total penetration of renewable energy will be dropped more. Notably, Wind power turned out to be proved only 10% of government goal because of its low availability.

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Current Approaches in Development of Immunotherapeutic Vaccines for Breast Cancer

  • Allahverdiyev, Adil;Tari, Gamze;Bagirova, Melahat;Abamor, Emrah Sefik
    • Journal of Breast Cancer
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    • v.21 no.4
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    • pp.343-353
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    • 2018
  • Cancer is the leading cause of death worldwide. In developed as well as developing countries, breast cancer is the most common cancer found among women. Currently, treatment of breast cancer consists mainly of surgery, chemotherapy, hormone therapy, and radiotherapy. In recent years, because of increased understanding of the therapeutic potential of immunotherapy in cancer prevention, cancer vaccines have gained importance. Here, we review various immunotherapeutic breast cancer vaccines including peptide-based vaccines, whole tumor cell vaccines, gene-based vaccines, and dendritic cell vaccines. We also discuss novel nanotechnology-based approaches to improving breast cancer vaccine efficiency.

Effects of Noradrenaline on the Spontaneous Contraction and Ionic Current in the Antral Circular Muscle of Guinea-pig Stomach

  • Jun, Jae-Yeoul;Lee, Sang-Jin;Kim, Sung-Joon;Suh, Jae-Yul;So, In-Suk;Hwang, Sang-Ik;Kim, Ki-Whan
    • The Korean Journal of Physiology
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    • v.27 no.2
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    • pp.115-122
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    • 1993
  • There is evidence that noradrenaline enhances spontaneous contractions dose-dependently in guinea-pig antral circular muscle. To investigate the mechanism of this excitatory action, slow waves and membrane currents were recorded using conventional microelectrode techniques in muscle strips and the whole cell patch clamp technique in isolated gastric myocytes. On recording slow waves, noradrenaline $(10^{-5}\;M)$ induced the hyperpolarization of the membrane potential, although the shape of the slow waves became tall and steep. Also, spike potentiaIs occurred at the peaks of slow waves. These changes were completely reversed by administration of phentolamine $(10^{-5}\;M),\;an\;{\alpha}-adrenoceptor$ blocker. Noradrenaline-induced hyperpolarization was blocked by apamin $(10^{-7}\;M)$, a blocker of a class of $Ca^{2+}\;-dependent\;K^+$ channels. To investigate the mechanisms for these effects, we performed whole cell patch clamp experiments. Norndrenaline increased voltage-dependent $Ca^{2+}$ currents in the whole range of test potentials. Noradrenaline also increased $Ca^{2+}\;-dependent\;K^+$\;currents, and this effects was abolished by apamin. These results suggest that the increase in amplitude and the generation of spike potentials on slow waves was caused by the activation of voltage-dependent $Ca^{2+}$ channel via adrenoceptors, and hyperpolarization of the membrane potential was mediated by activation of apamin-sensitive $Ca^{2+}\;-dependent\;K^+\;channels$.

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Inhibitory Effect of Immunoglobulin E Production by Poncirus tripoliata (지실(枳實)에 의한 면역(免疫)글로블린 E 생성(生成)의 억제효과(抑制效果))

  • Kim, Hyeong-Kyun;Kweon, Yong-Taek
    • The Journal of Korean Medicine
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    • v.19 no.1
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    • pp.419-429
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    • 1998
  • Poncirus trifoliata (L.) Raf (Rutaceae) fruits (PTFE) has been used for the treatment of allergic disease. IgE is normally one of the least abundant immunoglobulin (Ig) isotypes in the serum of both humans and several species of experimental animals: however a number of different stimuli can result in profound increases in IgE levels relative to other isotypes. In rodents, infection with many parasitic helminths can cause approximately 100-fold elevation in IgE within 2 wks. Immunization of mice with small amounts of protein antigens on alum also results in 10-fold to fold increase in total serum IgE, much of it specific for the immunizing antigen. In this experiment, I investigated the effect of an aqueous extract of Poncirus trifoliata (L.) Raf (Rutaceae) fruits (PTFE) on a in vivo and in vitro IgE production. PTFE dose-dependently inhibited the serum levels of IgE induced by antigens. The regulation of IgE synthesis is influenced by T cells and T cell derived factors. IL -4, a T cell-derived cytokine, has been shown to stimulate murine IgE synthesis both in vitro and in vivo. Current evidence suggests that IL-4 induces IgE synthesis in the mouse by stimulating H chain isotype switch. Lipopolysaccharide (LPS) plus IL-4 cause about l00-fold increase in IgE secretion by murine B cells. The effects of PTFE on the IL-4-dependent IgE response by mouse whole spleen cells were studied. Whole spleen cells were cultured for 7 days in the presence of LPS plus IL-4 and PTFE and the supernatants were assayed for IgE. IL-4 dependent IgE production of LPS-stimulated whole spleen cells was inhibited by PTFE. Moreover, in the present study using U266Bl human IgE-bearing B cells, I found that PTFE inhibited the production of IgE activated by LPS plus IL-4. These results indicate that PTFE have antiallergic activity by inhibition of IgE production from B cells.

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Electrical characteristics of voltage-dependent $Ca^{++}$ channel in rat chromaffin cell. (흰쥐 부신수질 세포에서 voltage-dependent $Ca^{++}$ 채널의 전기적 특성에 관한 연구)

  • Goo, Yong-Sook;Lee, Tae-Soo;Cha, Eun-Jong
    • Proceedings of the KOSOMBE Conference
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    • v.1994 no.05
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    • pp.142-145
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    • 1994
  • Calcium(Ca) ion plays an important role to trigger the secretion of important neurotransmitters. Since Ca ion flows into the cell thru the ion selective channel, the conductance of which depends on the transmembrane potential, the voltage-dependent characteristic of Ca ion channel is crucial to elucidate the stimulus-secretion coupling of exocytosis. The present study measured the Ca ion currents thru a whole-cell configuration patch at the transmembrane potential clamped at various desired levels in the rat chromaffin cell. The resultant current-voltage relationship was differentiated to obtain dynamic conductance at each clamped voltage. Based on these measured data, five numerical parameters were extracted to reveal electrical properties of Ca ion inflow process thru the voltage-gated channel. The present study can be applied to comparing the electrical characteristics of Ca channel under different experimental conditions. Also, further study is warranted to model the conformational changes of the channel molecules.

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Localization, activation and deactivation of $Ca^{2+}$ dependent $Cl^-$ channels in pancreatic acinar cells

  • Park, Myoung-Kyu;Richard Lomax;Alexei V. Tepikin;Ole H. Petersen
    • Proceedings of the Korean Biophysical Society Conference
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    • 2001.06a
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    • pp.27-27
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    • 2001
  • In exocrine acinar cells, $Ca^{2+}$ -activated Cl$^{[-10]}$ channels in the apical membrane are essential for fluid secretion, but it is unclear whether such channels are important for Cl$^{[-10]}$ uptake at the base. Whole cell current recording, combined with local uncaging of caged $Ca^{2+}$, was used to reveal the Cl$^{[-10]}$ channel distribution in mouse pancreatic acinar cells, where ~90% of the current activated by $Ca^{2+}$ in response toacetylcholine was carried by Cl$^{[-10]}$ .(omitted)

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Role of Protein Kinase C on Norepinephrine Induced Inhibition of Calcium Current in Rat Sympathetic Neurons (흰쥐 교감신경세포에서 Norepinephrine 에 의한 칼슘전류 억제에 미치는 Protein Kinase C 의 역할)

  • ;Keith S. Elmslie
    • Progress in Medical Physics
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    • v.11 no.1
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    • pp.29-38
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    • 2000
  • The signal transduction pathway for most neurotransmitter induced inhibition of $Ca^{2+}$ channels in sympathetic neurons involves a G-protein mediated, membrane-delimited mechanism without the participation of any known protein kinase. However, activation of protein kinase C (PKC) has been proposed as one of the intracellular mechanisms mediating some neurotransmitter induced $Ca^{2+}$ channel inhibition. In the present study, we investigated the effects of phorbol-12, 13-dibutyrate (PDBu) on $Ca^{2+}$ channel currents of acutely dispersed neurons from adult rat superior cervical ganglion (SCG) neurons using whole cell variant of the patch clamp technique. PDBu (500 nM), the activator of PKC, increased $Ca^{2+}$ channel currents and retarded the deactivation of tail currents. The effects of PDBu were voltage dependent and the maximal increase in the current amplitudes was observed between -10 to 10 mV (n=4). PDBu attenuated $Ca^{2+}$ current inhibition induced by norepinephrine (NE), which modulates $Ca^{2+}$ channels via a pertussis toxin (PTX)-sensitive pathway. Inhibition of PDBu by staurosporine (1 $\mu$M) blocked the effects of PDBu on current amplitudes and NE-induced G-protein mediated inhibition of $Ca^{2+}$ currents. Further experiment should be done to know if G-protein or $Ca^{2+}$ channel itself is the target of PKC phosphorvlation.phosphorvlation.

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Calcium current on cryopreservation in mouse oocytes (동결 생쥐 난자에서의 calcium 전류)

  • Kang, Da-Won;Kim, Eun-Sim;Choe, Chang-Yong;Park, Jae-Yong;Han, Jae-Hee;Hong, Seong-Geun
    • Korean Journal of Veterinary Research
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    • v.42 no.1
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    • pp.35-43
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    • 2002
  • Cryopreservation is commonly used for an efficient utilization of semen, oocytes and embryos but has disadvantage in the survival, development of the post-thawed eggs. The high risk in the survival, development of eggs after thawing is thought to be caused by inappropriate internal regulation of $Ca^{2+}$ and/or formation of intracellular ice crystals. In this experiment, we tested whether the $Ca^{2+}$ current (iCa), a decisive factor to $Ca^{2+}$ entry, was altered in post-thawed oocytes by using whole cell voltage clamp technique. The quality and survival rates of the oocytes derived from both fresh and frozen groups were examined by morphology and FDA-test. Vitrified oocytes (VOs) were incubated for 4 hr after thawing and then donated to this experiment. Ethyleneglycol-ficoll-galactose (EFG) was used as a cryoprotectant for vitrification. The membrane potential was held at -80 mV and step depolarizations of 250 ms were applied from -50 mV to 50 mV in 10 mV increments. The survival rates showed a higher in VOs vitrified with EFG containing $Ca^{2+}$ than in VOs vitrified with EFG under the $Ca^{2+}$-free condition (82.0% vs 14%). In group with/without $Ca^{2+}$, the survival rates were significantly (P<0.01) difference. In the fresh metaphase II oocytes (FOs), current-voltage (I-V) relationship showed that iCa began to activate at -40 mV and reached its maximum at -10 mV. With same voltage pulses, inward currents were elicited in VOs. I-V relationships observed in VOs were similar to those in FOs. Time constants of activation and inactivation of the inward current shown in VOs were not different to those in FOs. This accordance in I-V relations and time constants in FOs with those in VOs indicates that the inward currents in FOs are unaltered by vitrification and thawing. Therefore, vitrification with EFG does not play as a factor to deteriorate $Ca^{2+}$ entry across the membrane of the oocytes.