• Title/Summary/Keyword: Rb3

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Permeability properties of skeletal muscle ATP-sensitive K+ channels reconstituted into planar lipid bilayer (평지방막에 융합된 골격근의 single ATP-sensitive K+ channel의 이온투과성에 대한 연구)

  • Ryu, Pan-dong
    • Korean Journal of Veterinary Research
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    • v.32 no.4
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    • pp.543-553
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    • 1992
  • 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.

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Distribution Characteristics of Gold in the Volcanic Rocks, Korea (국내에 분포하는 화산암류중 금의 분포특징에 관한 연구)

  • Yoon, Chung-Han;Oh, Keun-Chang
    • Economic and Environmental Geology
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    • v.29 no.3
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    • pp.257-267
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    • 1996
  • One hundred of thirty volcanic rocks col1ected from the Jeju island, Jeongog, Guryongpo and other areas were analyzed for major elements and trace elements with Au by inductively coupled argon plasma and graphite furnace atomic absorptiom spectrometry. The Au content is the highest values (0.2~43.4 ppb, average; 10.34 ppb) from the Jeju island volcanic rocks and the lowest (0.5~11.0 ppb, average; 1.23 ppb) from the Guryongpo volcanic area. The content of Au tends to be higher in the Quarternary volcanic rocks than Tertiary or Cretaceous volcanic rocks. The Au content of the calc alkali volcanic rocks tends to increase from mafic to felsic volcanic rocks, but that of the alkalic volcanic rocks tends to increase from felsic to mafic volcanic rocks. The Au content of the volcanic rocks collected from the Jeju island shows the highest values in the feldspar olivine basalts. Elements or oxides which have positive or negative correlations with Au are Ag, Mo, Rb, V, Y, $K_2O$, MgO and $SiO_2$, but other elements analyzed are not shown correlations with Au. It has a tendency to show that samples from the Jeju with 5 ppb gold and more are plotted in the non-Dupal area and those with less than 5 ppb gold in the Dupal area, while those from the Jeongog with 5 ppb gold and more are plotted in the Dupal area and those with less than 5 ppb gold in the non-Dupal area, in the Ba/Nb-La/Nb, Zr/Nb-Ba/Nb diagrams. It shows that samples from the Jeju and Guryongpo with high gold content are plotted in the within-plate, while those with low gold content are plotted in the arc-related area, and those from the Jeongog are scattered in the $TiO_2-Al_2O_3$, $Zr/A1_2O_3-TiO_2/Al_2O_3$ diagrams.

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Effects of Glipizide on the Pharmacokinetics of Losartan after Oral and Intravenous Administration in Rats (흰쥐에서 글리피지드가 로살탄의 약물동태에 미치는 영향)

  • Yoo, Jin-Wook;Choi, Jin-Seok;Choi, Jun-Shik
    • YAKHAK HOEJI
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    • v.55 no.3
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    • pp.240-246
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    • 2011
  • The present study was to investigate the effect of glipizide on the pharmacokinetics of losartan in rats. Losartan was administered intravenously (3 mg/kg) and orally (9 mg/kg) in the presence and absence of glipizide (0.3 and 1 mg/kg) to rats. The pharmacokinetic parameters of losartan were significantly altered by the presence of glipizide compared with the control group (given losartan alone). Presence of glipizide significantly (p<0.05, 0.3 mg/kg) increased the area under the plasma concentration-time curve (AUC) of losartan by 48.2% and peak plasma concentration ($C_{max}$) of losartan by 47.4%. Consequently, the absolute bioavailability (AB%) of losartan in the presence of glipizide was 38%, which was enhanced significantly (p<0.05) compared to that in the oral control group (25%). The relative bioavailability (RB%) of losartan increased by 1.18- to 1.48-fold in the presence of glipizide. However, there was no significant change in the peak plasma concentration ($T_{max}$) and terminal half-life ($T_{1/2}$) of losartan in the presence of glipizide. In contrast, glipizide did not affect the pharmacokinetics of intravenous losartan. In conclusion, the presence of glipizide significantly enhanced the oral bioavailability of losartan, implying that glipizide might be mainly to inhibit the cytochrome P450 (CYP) 2C9-mediated metabolism, resulting in reducing gastrointestinal and/or hepatic first-pass metabilism of losartan rather than in reducing P-glycoprotein-mediated efflux and renal elimination of losartan. Concurrent use of glipizide with losartan should require close monitoring for potential drug interactions.

Improved antimicrobial effect of ginseng extract by heat transformation

  • Xue, Peng;Yao, Yang;Yang, Xiu-shi;Feng, Jia;Ren, Gui-xing
    • Journal of Ginseng Research
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    • v.41 no.2
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    • pp.180-187
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    • 2017
  • Background: The incidence of halitosis has a prevalence of 22-50% throughout the world and is generally caused by anaerobic oral microorganisms, such as Fusobacterium nucleatum, Clostridium perfringens, and Porphyromonas gingivalis. Previous investigations on the structure-activity relationships of ginsenosides have led to contrasting results. Particularly, the antibacterial activity of less polar ginsenosides against halitosis-related bacteria has not been reported. Methods: Crude saponins extracted from the Panax quinquefolius leaf-stem (AGS) were treated at $130^{\circ}C$ for 3 h to obtain heat-transformed saponins (HTS). Five ginsenoside-enriched fractions (HTS-1, HTS-2, HTS-3, HTS-4, and HTS-5) and less polar ginsenosides were separated by HP-20 resin absorption and HPLC, and the antimicrobial activity and mechanism were investigated. Results: HPLC with diode-array detection analysis revealed that heat treatment induced an extensive conversion of polar ginsenosides (-Rg1/Re, -Rc, -Rb2, and -Rd) to less polar compounds (-Rg2, -Rg3, -Rg6, -F4, -Rg5, and -Rk1). The antimicrobial assays showed that HTS, HTS-3, and HTS-4 were effective at inhibiting the growth of F. nucleatum, C. perfringens, and P. gingivalis. Ginsenosides-Rg5 showed the best antimicrobial activity against the three bacteria, with the lowest values of minimum inhibitory concentration and minimum bactericidal concentration. One major reason for this result is that less polar ginsenosides can more easily damage membrane integrity. Conclusion: The results indicated that the less polar ginsenoside-enriched fraction from heat transformation can be used as an antibacterial agent to control halitosis.

Development of Framework for Integrated Work-Risk Breakdown Structurebased on Fatal Incident Cases in Construction Industry (중대재해 사례에 기반한 건설업의 작업 및 위험분류체계 통합 프레임워크 개발)

  • Jeong, Jaemin;Jeong, Jaewook
    • Korean Journal of Construction Engineering and Management
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    • v.21 no.3
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    • pp.11-19
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    • 2020
  • Since an accident in construction industry has been higher than others for decades, the accident in construction industry should be decreased. To prevention this problem, the work breakdown structure (WBS) and risk breakdown structure (RBS) are presented. the WBS and RBS, are hierarchy structure which can find fatal incident considering type of building and type of work easily and quickly. So, this study aims to develop framework for the integrated WBS-RBS to prevent fatal incident on construction industry. The research process is conducted by following 3 steps: (I) collection of data; (II) classification of data; and (III) development of the integrated WBS-RBS. The result of this study can propose the most dangerous fatal incident aspect of type of building, type of work, and type of accident. Through the result, the decision maker can reduce or eliminate fatal incident considering type of building, type of work and type of accident in construction industry.

Chemical and bioactive comparison of Panax notoginseng root and rhizome in raw and steamed forms

  • Xiong, Yin;Chen, Lijuan;Man, Jinhui;Hu, Yupiao;Cui, Xiuming
    • Journal of Ginseng Research
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    • v.43 no.3
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    • pp.385-393
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    • 2019
  • Background: The root and rhizome are historically and officially utilized medicinal parts of Panax notoginseng (PN) (Burk.) F. H. Chen, which in raw and steamed forms are used differently in practice. Methods: To investigate the differences in chemical composition and bioactivities of PN root and rhizome between raw and steamed forms, high-performance liquid chromatography analyses and pharmacologic effects evaluated by tests of anticoagulation, antioxidation, hemostasis, antiinflammation, and hematopoiesis were combined. Results: With the duration of steaming time, the contents of ginsenosides $Rg_1$, Re, $Rb_1$, Rd, and notoginsenoside $R_1$ in PN were decreased, while those of ginsenosides $Rh_1$, $20(S)-Rg_3$, $20(R)-Rg_3$, $Rh_4$, and $Rk_3$ were increased gradually. Raw PN samples steamed for 6 h at $120^{\circ}C$ with stable levels of most constituents were used for the subsequent study of bioeffects. Raw PN showed better hemostasis, anticoagulation, and antiinflammation effects, while steamed PN exhibited stronger antioxidation and hematopoiesis activities. For different parts of PN, contents of saponins in PN rhizome were generally higher than those in the root, which could be related to the stronger bioactivities of rhizome compared with the same form of PN root. Conclusion: This study provides basic information about the chemical and bioactive comparison of PN root and rhizome in both raw and steamed forms, indicating that the change of saponins may have a key role in different properties of raw and steamed PN.

Major plant nutrient-releasing patterns in the leachates from the soil incorporated rice hull biochar adjusted pH with dry fish powder (산도를 조절한 왕겨 바이오차와 어분 혼합물을 처리한 토양 침출수의 양분용출 패턴)

  • Jae-Lee Choi;DongKeon Lee;MinJeong Kim;JooHee Nam;ChangKi Shim;SeungGil Hong;JoungDu Shin
    • Journal of the Korea Organic Resources Recycling Association
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    • v.31 no.3
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    • pp.55-64
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    • 2023
  • This batch experiment was conducted to investigate the patterns of major plant nutrients in the leachates from the soil that was incorporated with rice hull biochar adjusted pH with dry fish powder utilizing rice hull biochar for loading the soil microorganisms. The rice hull biochar adjusted pH between 6.0 and 7.0, and the mixture ratio of rice hull biochar and dry fish powder was 4:6. The treatments consisted of three; the soil incorporated with rice hull biochar non-adjusted pH with dry fish powder as control (RB + DF), the soil incorporated with rice hull biochar adjusted pH by pyroligneous acid solution and dry fish powder (RBP+DF), and the soil incorporated with rice hull biochar adjusted pH by citric acid solution and dry fish powder (RBC+DF). NH4-N, NO3-N, PO4-P, and K concentrations in the leachates were analyzed during incubation. The accumulated NH4-N and PO4-P concentrations in the leachates from the RBC+DF treatment were the highest during leaching periods. The highest accumulated NO3-N and K concentrations in the leachates from the RBP+DF treatment were observed. It observed that NH4-N and PO4-P were more released in the adjusted citric acid solution, but NO3-N and K were less released than those in the pyroligneous acid solution due to their low absorption capacity. Furthermore, it is necessary to investigate crop growth responses to the soil incorporated with adjusted pH rice hull biochar and dry fish powder for loading soil microorganisms.

Petrochemical Study on the Cretaceous Volcanic Rocks in Kageo island, Korea (가거도(소흑산도)의 백악기 화산암류에 대한 암석화학적 연구)

  • 김진섭;백맹언;성종규
    • The Journal of the Petrological Society of Korea
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    • v.6 no.1
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    • pp.19-33
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    • 1997
  • This study reports the results about the petrography and geochemical characteristics of 10 representative volacanic rocks. The Cretaceous volcanic rocks distributed in the vicinity of the Kageo island composed of andesitic rocks, dacitic welded tuff, and rhyolitic rocks in ascending order. Sedimentary rock is the basement in the study area covered with volcanic rocks. Andesitic rocks composed of pyroclastic volcanic breccia, lithic lapilli tuff and cryptocrystallin lava-flow. Most dacitic rocks are lapilli ash-flow welded tuff. Rhyolitic rocks consists of rhyolite tuff and rhyolite lava flow. Rhyolite tuff are lithic crystal ash-flow tuff and crystal vitric ash-flow tuff with somewhat accidental fragments of andesitic rocks, but dacitic rocks. The variation of major and trace element of the volcanic rocks show that contents of $Al_2O_3$, FeO, CaO, MgO, $TiO_2$ decrease with increasing of $SiO_2$. On the basis of Variation diagrams such as $Al_2O_3$ vs. CaO, Th/Yb vs. Ta/Yb, and $Ce_N/YB_N$ vs. $Ce_N$, these rocks represent mainly differentiation trend of calc-alkaline rock series. On the discriminant diagrams such as Ba/La and La/Th ratio, Rb vs. Y + Nb, the volcanic rocks in study area belongs to high-K Orogenic suites, with abundances of trace element and ternary diagram of K, Na, Ca. According to the tectonic discriminant diagram by Wood, these rocks falls into the diestructructive continental margin. K-Ar ages of whole rocks are from andesite to rhyolite $97.0{\pm}6.8~94.5{\pm}6.6,\68.9{\pm}4.8,\61.5{\pm}4.9~60.7{\pm}4.2$ Ma, repectively. Volcanic rocks in study area show well correlation to the Yucheon Group in terms of rock age dating and geochemcial data, and derived from andesitic calc-alkaline magma that undergone low pressure fractional crystallization dominated plagioclase at <30km.

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Light Quality and Photoperiod Affect Growth of Sowthistle (Ixeris dentata Nakai) in a Closed-type Plant Production System (밀폐형 식물생산시스템에서 광질과 광주기에 따른 씀바귀의 생육)

  • Kim, Hye Min;Kang, Jeong Hwa;Jeong, Byoung Ryong;Hwang, Seung Jae
    • Horticultural Science & Technology
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    • v.34 no.1
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    • pp.67-76
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    • 2016
  • This study was conducted to examine the optimal environmental condition for promoting the growth of sowthistle as affected by light quality and photoperiod in a closed-type plant production system. Seeds were sown in 240-cell plug trays and then germinated for 3 days at a 24-hour photoperiod in a closed-type plant production system with LED lights (R:B:W = 8:1:1). Seedlings were transplanted and grown under 3 types of LED (R:B:W = 8:1:1, R:W = 3:7, or R:B = 8:2) and 4 photoperiods (24/0, 16/8, 8/16, or 4/20 hours) with $230{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ light intensity at a density of $20cm{\times}20 cm$. The experimental design was a randomized complete block design. Plants were cultured for 40 days un der the condition of $21{\pm}2^{\circ}C$ and $70{\pm}10%$ relative humidity after transplanting. Plants were fed with a recycling nutrient solution (pH 7.0 and EC $2.0dS{\cdot}m^{-1}$) contained in a deep floating tank. Fresh weight and dry weight of shoot or root, leaf length, and leaf area were the greatest in the photoperiod of 24/0 (light/dark) with RW LED. The highest number of leaves occurred in the photoperiod of 16/8 (light/dark) with RB LED, while the incidence of tip burn was higher in the photoperiod of 24/0 (light/dark) compared to the other treatments. Chlorophyll value was the highest in the 16/8 (light/dark) photoperiod and there was no significant difference by light quality. Chlorophyll fluorescence was the lowest in the photoperiod of 24/0 (light/dark) compared with other treatments. Therefore, in terms of economic feasibility and productivity for Ixeris dentata Nakai cultivation in a closed-type plant production system, the results obtained suggest that plants grew the best when kept in a photoperiod of 16/8 (light/dark) and light quality of combined LED RW (3:7).

Processed Vietnamese ginseng: Preliminary results in chemistry and biological activity

  • Le, Thi Hong Van;Lee, Seo Young;Kim, Tae Ryong;Kim, Jae Young;Kwon, Sung Won;Nguyen, Ngoc Khoi;Park, Jeong Hill;Nguyen, Minh Duc
    • Journal of Ginseng Research
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    • v.38 no.2
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    • pp.154-159
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    • 2014
  • Background: This study was carried out to investigate the effect of the steaming process on chemical constituents, free radical scavenging activity, and antiproliferative effect of Vietnamese ginseng. Methods: Samples of powdered Vietnamese ginseng were steamed at $120^{\circ}C$ for various times and thei extracts were subjected to chemical and biological studies. Results: Upon steaming, contents of polar ginsenosides, such as Rb1, Rc, Rd, Re, and Rg1, were rapidly decreased, whereas less polar ginsenosides such as Rg3, Rg5, Rk1, Rk3, and Rh4 were increased as reported previously. However, ocotillol type saponins, which have no glycosyl moiety at the C-20 position, were relatively stable on steaming. The radical scavenging activity was increased continuously up to 20 h of steaming. Similarly, the antiproliferative activity against A549 lung cancer cells was also increased. Conclusion: It seems that the antiproliferative activity is closely related to the contents of ginsenoside Rg3, Rg5, and Rk1.