동물과 사람유래 Vancomycin 내성 장구균의 항균제 감수성 비교

조윤상,이희수,김종만,류판동,박용호,유한상,이문한 한국수의공중보건학회 2003 예방수의학회지 Vol.27 No.1

It has been recently reported the possibility in the bansfer of antimicrobial resistance to other animals and humans. In particular, vancomycin resistant enterococci (VRE), which have been known as a principal antimicrobial resistant bacteria in humans, have been increased as a pathogen of nosocomial infections. And then animal VRE were suspected as an origin of human VRE. In this study, we isolated Enterococcus spp. from animals, identified by bio- chemical tests, examined for antimicrobial susceptibility, and then compared the antimicrobial susceptibility of VRE among each other as well as human VRE. Enterococcus iecium (29%) was predominant in Enterococcus species (n=122) isolated from animal feces in this study. E. hirae, E. iecalis, E. casseliflam and E. gallinarum were also isolated as rates of 24%, 21%, 16% and 7%, respectively. The resistance of enterococci to penicillin and tetracycline were 66% and 78%, respectively, and the susceptibility of them to chloramphenicol was 66%. Antimicrobial susceptibility test has shown that 91% of VRE from humans (n=11) was susceptible to chloramphenicol and all resistant to penicillin, rifampin and streptomycin. Seventy-five percentage of VRE from chickens (n = 12) was susceptible to rifampin and resistances of them to penicillin, tetracycline and sbeptomycin were 75%, 83%, and l00%, respectively. Therefore, we confirmed the difference of antimicrobial susceptibility from animals and humans, and the antimicrobial susceptibility test could be one of the simple and useful methods for the epidemiological survey of VRE.

Random Amplified Polymorphic DNA Typing에 의한 동물과 사람 유래 Vancomycin 내성 장구균의 유전학적 비교

조윤상,이희수,김종만,류판동,박용호,유한상,이문한 한국수의공중보건학회 2003 예방수의학회지 Vol.27 No.1

It has been recently reported the possibility in the transfer of antimicrobial resistant to other animals and humans. In particular, the occurrence of vancomycin resistant enterococci (VRE), which have been known as a principal antimicrobial resistant bacteria in humans, has been increased as a pathogen of nosocomial infections. And then animal VRE were suspected as an origin of human VRE. In this work, we investigated the relatedness between VRE from animals and humans through random amplified polymorphic DNA (RAPD) typing. The genetic relatedness of vanA, vanB, vanC-1 and vanC-2 genotypes was examined by RAPD typing, respectively. van4 genotypes have not been shown high genetic relationship each other, containing VRE from humans (n = 8) and chickens (n = 5). In vanB genotypes from humans (n = 3), 2 isolates were made up one cluster, shown 77.8% homology. Chicken isolates of vanC-1 genotypes (n = 11) were constituted 2 clusters and the homology of 2 clusters was 81.8% and 80.0%, respectively. In case of vanC-2 genotypes (n = 19), 2 isolates from pigs have been shown 76.9% homology. But, between VRE from animals and humans, the isolates of high genetic relationship could not be found and RAPD typing was a useful epidemiological method that could be confirmed the genetic relationship among VRE.

Anemia induced morphological changes in organ surface primo vascular tissue in anemia

Pan Dong Ryu,Chae Jeong Lim,Yiming Shen,So Yeong Lee 대한수의학회 2017 대한수의학회 학술대회발표집 Vol.2017 No.-

Refining article type and abstract structure

Pan Dong Ryu 대한수의학회 2024 Journal of Veterinary Science Vol.25 No.2

2020 Changes to the Journal of Acupuncture and Meridian Studies

Pan Dong Ryu 사단법인약침학회 2020 Journal of Acupuncture & Meridian Studies Vol.13 No.2

Mesothelial cells demarcatethe subunits of organ surface primo vascular tissue

Pan Dong Ryu,Chae Jeong Lim,Yeo Sung Yoon,So Yeong Lee 대한수의학회 2017 대한수의학회 학술대회발표집 Vol.2017 No.-

2019 Changes to the Journal of Veterinary Science

Pan Dong Ryu,Jae-Hak Park 대한수의학회 2019 Journal of Veterinary Science Vol.20 No.2

평지방막에 융합된 골격근의 single ATP-sensitive K⁺ channel의 이온투과성에 대한 연구

류판동,Ryu, Pan-dong 대한수의학회 1992 大韓獸醫學會誌 Vol.32 No.4

Properties of unitary ATP-sensitive $K^+$ channels were studied using planar lipid bilayer technique. Vesicles were prepared from bullfrog (Rana catesbeiana) skeletal muscle. ATP-sensitive $K^+$ (K (ATP)) channels were identified by their unitary conductance and sensitivity to ATP. In the symmetrical solution containing 200mM KCI, 10mM Hepes, 1mM EGTA and pH 7.2, single K (ATP) channels showed a linear current-voltage relations with slight inward rectification. Slope conductance at reversal potential was $60.1{\pm}0.43$ pS(n=3)). Micromolar ATP reversibly inhibited the channel activity when applied to the cytoplasmic side. In the range of -50~+50 mV, the channel activity was not voltage-dependent, but the channel gating within a burst was more frequent at negative voltage range. Varying the concentrations of external/internal KCl(mM) to 40/200, 200/200, 200/100 and 200/40 shifted reversal potentials to $-30.8{\pm}2.9$(n=3), $-1.1{\pm}2.7$(n=3), 10.5 and 30.6(mV), respecrivety. These reversal potentials were close to the expected values by the Nernst equation, indicating nearly ideal selectivity for $K^+$ over $Cl^-$. Under bi-ionic conditions of 200mM external test ions and 200mM internal $K^+$, the reversal potentials for each test ion/K pair were measured. The measured reversal potentials were used for the calculation of the releative permeability of alkali cations to $K^+$ ions using the Goldman-Hodgkin-Katz equation. The permeability sequence of 5 cations relative to $K^+$ was $K^+$(1), $Rb^+$(0.49), $Cs^+$(0.27), $Na^+$(0.027) and $Li^+$(0.021). This sequence was recognized as Eisenman's selectivity sequence IV. In addition, modelling the permeation of $K^+$ ion through ATP-sensitive $K^+$ channel revealed that a 3-barrier 2-site multiple occupancy model can reasonably predict the observed current-voltage relations.

뇌허혈 발생전 K통로 조작이 해마의 [K+] 및 Glutamate 농도에 미치는 영향

조명원,류판동,최규택,박형섭,서병태,이정락 대한마취과학회 1999 Korean Journal of Anesthesiology Vol.36 No.3

Background : Cerebral ischemia causes an increase in extracellular potassium ([K ]e) through activation of the KATP channel. This increase in [K ]e could result in neuronal depolarization and a reversal of the glutamate uptake system in glia. This may further contribute to the excessive concentrations of glutamate and asparate in the extracellular space during ischemia. If the early rise in [K ]e during ischemia could be attenuated, less excitotoxic neuronal damage may be the result. However, activation of KATP channels has been shown to attenuate the anoxia induced depolarization in the hippocampus and may reduce the release of excitatory neurotransmitters during cerebral ischemia. In this study, we address the question of whether KATP channel modulation affects [K ]e and whether it is related with extracellular glutamate concentrations. Methods : After approval by the Animal Care and Use Committee, 18 New Zealand white rabbits were anesthetized with halothane and mechanically ventilated to maintain normocarbia. Microdialysis catheters were inserted into the left dorsal hippocampus and perfused with artificial cerebrospinal fluid at 2 ml/min. K sensitive microelectrodes were inserted into the contralateral hippocampus. A pneumatic tourniquet was placed loosely around the neck. Animals were randomized to receive glibenclamide (n=5, KATP blocker, 3.7 mg/kg) or cromakalim (n=5, KATP opener, 0.5 mg/kg). The control group (n=6) had neither drug. Ten-minute period of global cerebral ischemia was produced by inflation of the tourniquet combined with induced hypotension. Hippocampal [K ]e was measured throughout the periischemic period and glutamate concentrations in dialysate were determined by high-performance liquid chromatography. Peak levels were compared by ANOVA. Results : Glutamate concentration significantly increased during ischemia period for all groups (p<0.05). In glibenclamide treated animals, brain glutamate concentration increased markedly during early reperfusion (t=I 15) compared to other goups (p<0.05). There were no statistical differences on ischemia-induced increases in [K ]e among the three groups. Conclusions : Although it was not possible to demonstrate an effect of modulators of the ATP sensitive K channel on [K ]e, glibenclamide increased glutamate during reperfusion. This paradoxical increase in glutamate after administration of a K channel blocker suggests that the mechanism of glutamate release is not related to [K ]e change. (Korean J Anesthesiol 1999; 36: 510∼517)

Increased Activity of Large Conductance Ca<SUP>2⁢</SUP>-Activated K<SUP>⁢</SUP> Channels in Negatively-Charged Lipid Membranes

Jin Bong Park,Pan Dong Ryu 대한생리학회-대한약리학회 1998 The Korean Journal of Physiology & Pharmacology Vol.2 No.4

<P> The effects of membrane surface charge originated from lipid head groups on ion channels were tested by analyzing the activity of single large conductance Ca<SUP>2⁢</SUP>-activated K<SUP>⁢</SUP> (maxi K) channel from rat skeletal muscle. The conductances and open-state probability (P<SUB>o</SUB>) of single maxi K<SUB> </SUB>channels were compared in three types of planar lipid bilayers formed from a neutral phosphatidylethanolamine (PE) or two negatively-charged phospholipids, phosphatidylserine (PS) and phosphatidylinositol (PI). Under symmetrical KCl concentrations (3∼1,000 mM), single channel conductances of maxi K channels in charged membranes were 1.1∼1.7 times larger than those in PE membranes, and the differences were more pronounced at the lower ionic strength. The average slope conductances at 100 mM KCl were 251⁑9.9, 360⁑8.7 and 356⁑12.4 (mean⁑SEM) pS in PE, PS and PI membranes respectively. The potentials at which P<SUB>o</SUB> was 1/2, appeared to have shifted left by 40 mV along voltage axis in the membranes formed with PS or PI. Such shift was consistently seen at pCa 5, 4.5, 4 and 3.5. Estimation of the effect of surface charge from these data indicated that maxi K channels sensed the surface potentials at a distance of 8∼9 Å from the membrane surface. In addition, similar insulation distance (7∼9 Å) of channel mouth from the bilayer surface charge was predicted by a 3-barrier-2-site model of energy profile for the permeation of K<SUP>⁢</SUP> ions. In conclusion, despite the differences in structure and fluidity of phospholipids in bilayers, the activities of maxi K channels in two charged membranes composed of PS or PI were strikingly similar and larger than those in bilayers of PE. These results suggest that the enhancement of conductance and P<SUB>o</SUB> of maxi channels is mostly due to negative charges in the phospholipid head groups.