• Title/Summary/Keyword: $C_{max}$

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Abies koreana and Its New Forms Discovered (구상나무와 새로 발견(發見)된 품종(品種))

  • Lee, Tchang Bok
    • Journal of Korean Society of Forest Science
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    • v.10 no.1
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    • pp.5-6
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    • 1970
  • Abies koreansa Wilson grows at the upper part of Mts. Halla, Chiri, Mudung, Kaji and Dokyu. It was at first collected by Father U. Faurie on the May of 1907 from the Mt. Halla, Quelpaert. Cone colour of this species varies from green to black purple and the typical colour of it is violet purple. A form of black purple was named by Hatushima in 1934. Green and reddish brown or reddish purple colours of this species were discovered recently at the Mt. Halla. All these forms can be identified as the following. for. koreana - Abies koreana Wilson in Journ. Arn. Arb. 1, 188(1920) ; Mori, En. 27(1922) ; Uyeki, Timb. Tr. 117(1926) et Woody Pl. 5(1940) ; Chung et al, Comm. Nam. 12(1937) ; Handb. Kor. Manch. For. 71(1939) ; Kawamoto, III. For. P1. 16(1940) ; T. Lee, Arb. Kor. 12(1947) et Billiogr. Woody P1. 233(1966) ; Nakai, Synopt. 23(1952)-A. nephrolepis sensu Nakai, Rep. Veg. Chirisan 23, no. 27(1915) et Rep. Veg. Quelpaert Isl. 13, no. 142 (1915), non Max. (1866) Strobili violaceo-purpurei, bracteis viridibus juvenilibus vel stramineis matureis. Mt. Halla ( Lee, no. 970527K. ) for. chlorocarpa, forma nova ; Strobili et bracteae viridi sed rubescent in apice juvenili inflerescentiae. Mt. Halla ( Lee, no. 970527C. ) for. rubrocarpa, forma nova ; Strobili et bracteae rubro-purpurei vel rubro-fusui Mt. Halla ( Lee, no. 970527R. ) for nigrocarpa Hatushima, Rep. Exp. For. Kyushu U. 40(1934) ; T. Lee, Arb. Kor. 12(1947) et Bibliogr. Woody P1,233(1966). Strobili et bracteae nigro-purpurei. Mt. Halla (Lee, no. 970527N. )

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Effects of Baicalein on the Bioavailability of Nicardipine in Rats

  • Son, Hong-Mook;Choi, Jun-Shik
    • Journal of Pharmaceutical Investigation
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    • v.40 no.5
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    • pp.291-296
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    • 2010
  • This study was to investigate the effect of baicalein, an antioxidant, on the bioavailability of nicardipine after orally or intravenously administered nicardipine in rats. Nicardipine was administered orally (12 mg/kg) or intravenously (4 mg/kg) with or without orally administered baicalein (0.4, 2 or 10 mg/kg) to rats. In the inhibitory effect of baicalein on CYP3A4 activity, baicalein inhibited CYP3A4 activity with $IC_{50}$ values of 9.2 ${\mu}M$. The cell-based P-gp activity test using rhodamine-123 also showed that baicalein (30-10 ${\mu}M$, p<0.01) significantly inhibited P-gp activity. Compared with the control group (given nicardipine alone), the area under the plasma concentration-time curve (AUC) was significantly (2 mg/kg, P<0.05; 10 mg/kg, P<0.01) increased by 25.9-60.0%, and the peak concentration ($C_{max}$) was significantly (10 mg/kg, P<0.01) increased by 40.0% in the presence of baicalein after orally administration of nicardipine. Consequently, the relative bioavailability (R.B.) of nicardipine was increased by 1.26- to 1.60-fold and the absolute bioavailability (A.B.) was significantly (2 mg/kg, P<0.05; 10 mg/kg, P<0.01) increased by 26.0-59.9%. Compared to the i.v. control, baicalein did not significantly change pharmacokinetic parameters of nicardipine in i.v. administration. Accordingly, the enhanced oral bioavailability of nicardipine might be mainly due to increased intestinal absorption caused by P-gp inhibition rather than to reduced elimination of nicardipine by baicalein. The increase in the oral bioavailability might be mainly attributed to enhanced absorption in the small intestine via the inhibition of P-gp and reduced first-pass metabolism of nicardipine via the inhibition of the CYP3A subfamily in the small intestine and/or in the liver by baicalein. Based on these results, nicardipine dosage should be adjusted when given concomitantly with baicalein.

Isolation of an Acinetobacter junii SY-01 Strain Producing an Extracellular Lipase Enantioselectively Hydrolyzing Itraconazole Precursor, and Some Properties of the Lipase

  • Yoon, Moon-Young;Shin, Pyong-Kyun;Han, Ye-Sun;Lee, So-Ha;Park, Jung-Keug;Cheong, Chan-Seong
    • Journal of Microbiology and Biotechnology
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    • v.14 no.1
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    • pp.97-104
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    • 2004
  • Water-sludge bacteria were screened to find a lipase enantioselectively hydrolyzing itraconazole precursor, which is well known as the starting material of antifungal drug agents. A bacterial strain was isolated and identified as Acinetobacter junii SY-01. After the strain was cultivated, the enzyme was purified 39.4-fold using ultrafiltration and gel filtration through a Sephadex G-100 chromatographic column and the activity yield was 34.9%. The molecular weight of the enzyme was about 40 kDa, as measured by SDS-PAGE, and the optimum pH was 7.0- 9.0 and stable at pH 6.0- 9.0. The optimum temperature was 45- $5^{\circ}C$, and 73% of the enzymes activity remained after incubation at 70% for 1 h. Enzyme activity was enhanced by gall powder, sodium deoxycholate, a cationic detergent Tween 80, and a non-ionic detergent Triton X-100, but was markedly inhibited by metal ions such as $Hg^{2+},Cu^{2+},Ni^{2+}/,Ca^{2+}$, and an anionic-surfactant sodium dodecylsulfate. The $K_{m}$ values for (R)- and (S)-enantiomers of the itraconazole precursor were 0.385 and 21.83 mM, respectively, and the $V_{max} values ($\mu$Mㆍmin^{-1}.)$ were 6.73 and 6.49, respectively. The acetyl group among the different acyl moieties of itraconazole precursor showed the highest enantioselectivity for the hydrolysis by the Acinetobacter junii SY-01 lipase, and the lipase from Acinetobacter junii SY-01 displayed better enantioselectivity than that of commercially available lipases and esterases.

A New Salt-Tolerant Thermostable Cellulase from a Marine Bacillus sp. Strain

  • dos Santos, Yago Queiroz;de Veras, Bruno Oliveira;de Franca, Anderson Felipe Jacome;Gorlach-Lira, Krystyna;Velasques, Jannaina;Migliolo, Ludovico;dos Santos, Elizeu Antunes
    • Journal of Microbiology and Biotechnology
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    • v.28 no.7
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    • pp.1078-1085
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    • 2018
  • A salt-tolerant cellulase secreted by a marine Bacillus sp. SR22 strain with wide resistance to temperature and pH was purified and characterized. Its approximate mass was 37 kDa. The endoglucanase, named as Bc22Cel, was purified by ammonium sulfate precipitation, gel filtration chromatography, and extraction from the gel after non-reducing sodium dodecyl sufate-polyacrylamide gel electrophoresis. The optimal pH value and temperature of Bc22Cel were 6.5 and $60^{\circ}C$, respectively. The purified Bc22Cel showed a considerable halophilic property, being able to maintain more than 70% of residual activity even when pre-incubated with 1.5 M NaCl for 1 h. Kinetic analysis of the purified enzyme showed the $K_m$ and $V_{max}$ to be 0.704 mg/ml and $29.85{\mu}mol{\cdot}ml^{-1}{\cdot}min^{-1}$, respectively. Taken together, the present data indicate Bc22Cel as a potential and useful candidate for industrial applications, such as the bioconversion of sugarcane bagasse to its derivatives.

Response of $I_{Kr}$ and hERG Currents to the Antipsychotics Tiapride and Sulpiride

  • Jo, Su-Hyun;Lee, So-Young
    • The Korean Journal of Physiology and Pharmacology
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    • v.14 no.5
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    • pp.305-310
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    • 2010
  • The human $ether$-$a$-$go$-$go$-related gene ($hERG$) channel is important for repolarization in human myocardium and is a common target for drugs that prolong the QT interval. We studied the effects of two antipsychotics, tiapride and sulpiride, on hERG channels expressed in $Xenopus$ oocytes and also on delayed rectifier $K^+$ currents in guinea pig cardiomyocytes. Neither the amplitude of the hERG outward currents measured at the end of the voltage pulse, nor the amplitude of hERG tail currents, showed any concentration-dependent changes with either tiapride or sulpiride ($3{\sim}300{\mu}M$). However, our findings did show that tiapride increased the potential for half-maximal activation ($V_{1/2}$) of HERG at $10{\sim}300{\mu}M$, whereas sulpiride increased the maximum conductance ($G_{max}$) at 3, 10 and $100{\mu}M$. In guinea pig ventricular myocytes, bath applications of 100 and $500{\mu}M$ tiapride at $36^{\circ}C$ blocked rapidly activating delayed rectifier $K^+$ current ($I_{Kr}$) by 40.3% and 70.0%, respectively. Also, sulpiride at 100 and $500{\mu}M$ blocked $I_{Kr}$ by 38.9% and 76.5%, respectively. However, neither tiapride nor sulpiride significantly affected the slowly activating delayed rectifier $K^+$ current ($I_{Ks}$) at the same concentrations. Our findings suggest that the concentrations of the antipsychotics required to evoke a 50% inhibition of IKr are well above the reported therapeutic plasma concentrations of free and total compound.

A Study of the Inhibitory Effect of Acer tegmentosum Max. on Fibrogenesis in Hepatic Stellate Cell Line T6 (산청목(山靑木)이 간섬유화 진행 억제에 미치는 효과에 대한 연구)

  • Lee, Seung-Bo;Woo, Hong-Jung
    • The Journal of Internal Korean Medicine
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    • v.31 no.2
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    • pp.346-355
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    • 2010
  • Objectives : This study was performed in order to investigate the anti-fibrogenic effect of Acer tegmentosum Maxim. on r at hepatic stellate cell line T6. Materials and Methods : Hepatic stellate Cells (T6) were treated with various concentrations of distilled water Acer teg mentosum Maxim. extract for 24, 48, 72 hours. After the treatment, cell viability, proliferation, procollagen levels, mRNA of AS MA, MMP-2, collagen type 1a2 and IL-6 production were measured using MTT assay, BrdU assay, RT-PCR, procollagen typ e 1 C-peptide EIA kit and murine IL-6 ELISA development kit. Results : Cell viability of HSC-T6 decreased significantly in both 24 hours and 48 hours groups in a dose-dependant man ner. Proliferation of HSC also decreased in the same way. In the RT-PCR, mRNA expression of collagen type 1a2 and ASMA decreased in the groups which were treated with Acer tegmentosum Maxim. for 24 hours. The production of procollagen tended to decrease in a dose-dependant manner in the 24 hours treated group. IL-6 production increased under Acer tegmentosum trea tment in a dose-dependant manner in both 24 and 48 hours groups. Conclusion : These results show the possibility that Acer tegmentosum Maxim. can be an effective remedy for liver fibrosi s and liver cirrhosis.

Stability, Efficacy, Absorption and Toxicity of a New Nasal Spray Formulation including Salmon Calcitonin

  • Shim, Hyun-Joo;Kim, Mi-Kyung;Bae, En-Joo;Lee, Eung-Doo;Hyun Jo;Kim, Soon-Hae;Kwon, Jong-Won;Kim, Won-Bae
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1998.11a
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    • pp.137-137
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    • 1998
  • Stability, efficacy, absorption and toxicity of a new nasal spray formulation including salmon calcitonin were studied in the laboratory animals. After the effects of many excipients on the stability of salmon calcitonin were evaluated using HPLC system, we selected taurine. Our experimental composition of salmon calcitonin contains taurine as a stabilizer and HPMC (hydroxypropylmethyl cellulose) as an adhesive polymer. After intranasal administration of salmon calcitonin formulations, Mia$\^$(R)/, Men$\^$(R)/ and experimental composition, 22 IU to rats, the reduction percentages of calcium concentration in plasma (ΔD%) were 16.3%, 12.9% and 20.8%, respectively. After intranasal administration of Mia$\^$(R)/, Men$\^$(R)/ and experimental composition to rats, C$\sub$MAX/ (205${\pm}$161, 244${\pm}$117, and 330${\pm}$202 pg/$m\ell$, respectively) and AUC (41585${\pm}$22070, 41191${\pm}$19125, and 63357${\pm}$43126 pg. min/$m\ell$, respectively) were calculated. The permeation coefficients 10$\^$-7/,cm/sec) of salmon calcitonin in Mia$\^$(R)/, Men$\^$(R)/ and experimental composition using Ussing chamber with rabbit nasal mucosa were 4.7${\pm}$1.5, 0.75${\pm}$0.4 and 5.3${\pm}$1.1, respectively. The experimental composition with taurine and HPMC was proved to be excellent because it improved the stability of salmon calcitonin and inhanced the absorption of salmon calcitonin and was not irritative to the nasal mucosa.

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Identification of QTLs controlling somatic embryogenesis using RI population of cultivar ${\times}$ weedy soybean

  • Choi, Pilson;Mano, Yoshiro;Ishikawa, Atsuko;Odashima, Masashi;Umezawa, Taishi;Fujimura, Tatsuhito;Takahata, Yoshihito;Komatsuda, Takao
    • Plant Biotechnology Reports
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    • v.4 no.1
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    • pp.23-27
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    • 2010
  • Quantitative trait loci (QTLs) controlling ability of somatic embryogenesis were identified in soybean. A frame map with 204-point markers was developed using an RI population consisting of 117 $F_{11}$ lines derived from a cross between cultivar 'Keburi' and a weedy soybean 'Masshokutou Kou 502'. The parents differed greatly in their abilities of somatic embryogenesis using immature cotyledons as explants. The ability of somatic embryogenesis was evaluated in five different experiments: the $F_{11}$ (evaluated in 1998) and $F_{15}$ (2002) generations cultured on basal media supplemented with $40\;mg\;l^{-1}$ 2,4-D (2,4-D1998 and 2,4-D2002), $F_{14}$ (2001) generation on medium with $40\;mg\;l^{-1}$ 2,4-D and high sucrose concentration [2,4-D2001 ($30\;g\;l^{-1}$ sucrose)], and the $F_{11}$ (1998) and $F_{12}$ (1999) generations on medium with $10\;mg\;l^{-1}$ NAA (NAA1998 and NAA1999). The RILs showed wide and continuous variations in each of the five experiments. In the composite interval mapping analysis, 2 QTLs were found in group 8 (D1b + W, LOD = 5.42, $r^2$ = 37.5) in the experiment of 2,4-D1998 and in group 6 (C2, LOD = 6.03, $r^2$ = 26.0) in the experiment of 2,4-D2001 (high concentration sucrose). In both QTLs, alleles of 'Masshokutou Kou 502' with high ability of somatic embryogenesis contributed to the QTLs. For the other three experiments, no QTL was detected in the criteria of LOD >3.0, suggesting the presence of minor genes.

Weed Occurrence and Control at Soybean Culture in Rice-Soybean Rotated Paddy Field (답전윤환(畓田輪換) 콩 재배지(栽培地)에서의 잡초발생(雜草發生) 및 방제(防除))

  • Kim, K.U.;Shin, D.H.;Park, S.J.;Jeong, J.W.;Hwang, S.S.
    • Korean Journal of Weed Science
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    • v.15 no.4
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    • pp.313-320
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    • 1995
  • The major weeds observed in soybean(Glycine max(L.) Merr.) culture at the paddy field where transplanted rice was cultivated in previous year were Digitaria spp., Echinochloa spp., Chenopodium ficifolium, Rorippa islandica and Stellaria alsine. C. ficifolium and R. islandica increased as soybean was cultivated for two years in the same field. Weed biomass decreased by 84.8% as the seeding date was delayed from April 26 to May 20. Most of weeds started to emerge from 20 days after seeding(DAS) until 40 DAS, and higher seed yield was obtained by eliminating the weeds emerged until 40 DAS. The development of soybean branches, pods stem diameter was severely injured by weed interference, and thus soybean seed yield was reduced by 70% in comparison with a full season weed free plot. Herbicides such as pendimethalin, metolachlor, metolachlor+prometryn and alachlor controlled very effectively weeds present in soybean culture in rice-soybean rotated paddy field.

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Comparative Bioavailability of Ipriflavone by Pharmaceutical Preparation Types (제제헝태에 따른 이프리플라본의 생체이용률 비교)

  • Jeong, Je-Kyo;Khang, Gil-Son;Rhee, John M.;Shin, Ho-Chul;Lee, Hai-Bang
    • Journal of Pharmaceutical Investigation
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    • v.30 no.1
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    • pp.21-26
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    • 2000
  • Bioavailability of ipriflavone (3-phenyl-7-isopropoxy-4H-I-benzopyran-4-one, IP), an antiosteoporotic drug with poor water-solubility, was studied for various types of pharmaceutical preparation in SD rats. The IP preparation types included (1) intact IP, (2) freezer milled IP (FIP), (3) freezer milled IP physically mixed with freezer milled poly-N-vinylpyrrolidone (PVP) (FIP+FPVP) and (4) spray-dried IP with PVP (SIP). Upon oral administration, SIP showed significantly higher absorption and elimination half-lives and the lag time $(t_{lag})$ than those of FIP+FPVP (approximately 2-fold). These results may be due to a sustained releasing effect of IP in the gastrointestinal tract by spray-drying with PVP. The $C_{max}$ of SIP was about 2 and 10 times higher than those of FIP+FPVP and FIP, respectively. The AUC of SIP was about 6 times higher than that of FIP+FPVP and 60 times that of FIP. Scanning electron microscopy (SEM) showed that SIP consisted of the finest particle size and minimal aggregation than other IP preparations. It is concluded that the IP formula prepared by the spray-drying method with PVP is the most effective approach to the improvement of bioavailability of IP.

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