• 한국임상약학회지
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• 제15권1호
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• pp.46-49
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• 2005

A simple HPLC method was employed for the determination of pentoxifylline in human serum. After addition of internal standard (IS, 50 uL of 3 ug/mL chloramphenicol methanol solution) into the serum sample, the drug and IS were extracted by dichloromethane. Following a 1-min vortex-mixing and a 15-min centrifugation at 3500 게m, the organic phase was transferred and evaporated to dryness under a vacuum. The residue was reconstituted with 120 ${\mu}L$ of mobile phase and 50 ${\mu}L$ was injected into C18 column with a mobile phase composed of 0.034 M phosphoric acid adjusted to pH 4 with 10 M NaOH and acetonitrile (75:25, v/v). The samples were detected using an ultraviolet detector at 273 nm. The method was simple, specific and validated with a limit of 10 ng/mL. Intra- and inter-day precision and accuracy were acceptable for all quality control samples including the lower limit of quantification. The applicability of this method was evaluated by analysis of human serum after oral administration of a single 400 mg dose to 8 healthy subjects. The pharmacokinetic parameters for pentoxifylline in human subjects were calculated using WinNonlin program. As a result, $AUC_{t},\;C_{max},\;T_{max}$ and $t_{1/2}$ were $962.28{\pm}645.69\;ng{\cdot}/mL$, $132.82{\pm}42.05$ ng/mL, $2.06{\pm}2.68$ hr and $8.74{\pm}4.38$ hr, respectively. Based on the results, this validated method appears to be useful fur the pharmnacokinetic study of pentoxifylline in humans.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권6호
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• pp.127-132
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• 2015

In this study, biochar-bead, prepared from biochar powder derived from woody biomass, was used for removal cadmium ion in aqueous solution. Various mixing ratios of alginate solution and biochar powder were used for the production of round shape biochar-bead. An optimum mixing ratio was selected as 1.5% alginate solution and 20 wt% biochar. The produced biochar-bead was characterized by SEM, FT-IR, and XRD analyses. The adsorption capacity of Cd(II) by biochar-bead was found to be 9.72 mg/g which was higher than that by GAC and PAC. According to this study, round shape biochar-bead is expected to be used as a media for reactive barrier or water filtration.

• The Plant Pathology Journal
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• 제27권3호
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• pp.225-231
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• 2011

Previously, we identified the 20S proteasome ${\alpha}$-subunit of Magnaporthe oryzae (M. oryzae) induced during appressorium formation, and detected an increase in multiple protein ubiquitination during the early appressorium formation process (Kim et al., 2004). In this study, we further attempted to determine whether the proteasome is involved in the appressorium formation of M. oryzae both in vitro and in planta, using proteasome inhibitors. A significant increase in 20S proteasome during fungal germination and appressorium formation was observed using Western blot analysis with 20S proteasome antibody, demonstrating that proteasome-mediated protein degradation was involved in appressorium formation. Pharmacological analysis using proteasome inhibitors, MG-132, proteasome inhibitor I (PI) and proteasome inhibitor II (PII) revealed that germination and appressorium formation were delayed for 4 to 6 h on rice leaf wax-coated plates. Similarly, the treatment of proteasome inhibitors with fungal conidia on the rice leaf surface delayed appressorium formation and host infection processes as well. Additionally, fungal pathogenicity was strongly reduced at 4 days' postfungal infection. These data indicated that the fungal 20S proteasome might be involved in the pathogenicity of M. oryzae by the suppression of germination and appressorium formation.

• Journal of Pharmaceutical Investigation
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• 제35권1호
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• pp.51-55
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• 2005

A high-performance liquid chromatographic method was employed for the determination of bumetanide in human plasma. After addition of internal standard (IS, naproxen) and acidification of the plasma with 1 M hydrochloric acid, the drug and IS were extracted into dichloromethane. The organic phase was back-extracted into 1 M sodium bicarbonate solution and 50 ${\mu}l$ of the aqueous phase was injected onto a reversed-phase C18 column with a mobile phase consisting of methanol: water: glacial acetic acid = 65 : 35 : 1. The samples were detected utilizing a fluorescence detector (excitation wavelength 235 nm, emission wavelength 405 nm). The method was specific and validated with a lower limit of 5 ng/mL. Intra- and inter-day precision and accuracy were acceptable for all quality control samples including the lower limit of quantification. The applicability of the method was demonstrated by analysis of plasma after oral administration of a single 2 mg dose to 24 healthy subjects. From the plasma bumetanide concentration vs. time curves, the mean AUC was $246.5{\pm}73.8\;ng{\cdot}hr/mL$ and $C_{max}$ of $132.1{\pm}40.9$ ng/mL reached 1.2 hr after administration. The mean biological half-life of burnet ani de was $1.1{\pm}0.2$hr. Based on the results, this simple and validated assay method could readily be used in any pharmacokinetic or bioequivalence studies using humans.

• 한국가축번식학회지
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• 제12권3호
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• pp.132-140
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• 1988

These experiments were carried out to examine the development capacity of mouse blastomers separated from 2 to 8-cell stage mouse embryos. The female ICR and C3H mice were subjected to supervolution by intraperitoneal injection of PMSG and HCG and then mated with males of the same strain. Embryos were flushed from oviducts and uteri on a proper time after injection of HCG. After removal of zona pellucida with 0.5% pronase, each embryos were separated into 1/2, 1/4, 2/4, 1/8, 2/8 and 4/8 embryos by pipetting or a fine glass needle in Ca2＋$.$Mg-2＋ free Hoppe& Pitts medium containing 0.02% EDTA. Splitted embryos were cultured in Hoppe & Pitts medium for 48h to 72h. The embryos developed to blastocyst were transferred to recipients on 2 or 3 days of pseudopregnancy. On the other hand, a monozygotic pairs of 1/2 embryos developed to blastocyst after 48h in vitro culture were transferred to recipients on 2 days of pseudopregnancy or pregnancy. The results obtained were summarized as follows. 1. Success rates of separation of blastomeres from 2-, 4- and 8-cell embryos were 91.7%, 68.5-92.4% and 60.8-90.6%, respectively. 2. Development rates of various type of blastomeres to blastocyst after 72h in vitro culture were ranged 64.7-87.1%. 3. Blastocysts obtained after 48h in vitro culture were transferred to recipients on 2 or 3 days of pseudopregnancy. The production rates of live fetuses after transfer on 2 days, only 1/2, 2/4 and 4/8 embryos, were 13.2%, 13.5% and 17.2%, respectively and those of embryos transferred on 3 days were 11.8%, 9.6% and 11.5%, respectively. However, the production rates of live fetuses 1/2 embryos following 72h in vitro culture and transfer to recipients on 2 or 3 days of pseudopregnancy were 7.7% and 12.5%, respectively. 4. From 29 and 31 pairs of 1/2 embryos transferred to recipients on 2 days of pseudopregnancy or pregnancy, 4 sets of monozygotic twins were produced from only pregnant recipients.

• Journal of Microbiology and Biotechnology
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• 제8권4호
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• pp.353-360
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• 1998

A bacterial strain PN33 producing large amounts of extracellular pectin lyase (PNL, EC 4.2.2.10) was isolated from soil. The isolated bacterium was identified as a strain of Bacillus sp. Production of PNL by the strain was induced only by pectins, with a higher degree of esterification, which had been added to the culture medium as a sole carbon source. The optimal medium for PNL production was determined to consist of 10 g pectin, 2 g yeast extract, 4 g $K_2HPO_4{\cdot}3H_2O$, 0.6 g $MgSO_4$, and 0.11 g $CaCl_2$ per liter (pH 7.0). The PNL activity in the culture supernatant reached the highest level of 132 mU/ml after 32 h cultivation at $37^{\circ}C$ in the optimal medium. The PNL produced was purified to homogeneity by ammonium sulfate fractionation (50~80%), and cation exchange and size exclusion chromatographies. The molecular mass of the enzyme was estimated to be approximately 52 kDa by SDS-PAGE. Almost the same mass was determined by nondenaturing PAGE, indicating that the functional enzyme had a monomeric structure. As expected, the PNL exhibited higher activities on the highly esterified pectins whereas it gave no detectable activity on polygalacturonic acid. The enzyme showed the highest activity at the acidic pH of 6.0, exceptional for a bacterial PNL. Maximum activity was measured at $40^{\circ}C$, although the stability f the purified enzyme was poor at this temperature. alcium (1 mM) was found to activate the PNL activity by $50\%$, and also remarkably increased the thermal stability f the enzyme. Phenylmethylsulfonylfluoride (PMSF) and iethylpyrocarbonate (DEPC) inhibited the PNL activity lmost completely at the concentration of 5 mM. This result ndicates that some serine and histidine residues of the nzyme may play an essential role for catalytic function of he enzyme.

• Nutritional Sciences
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• 제7권3호
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• pp.127-132
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• 2004

The current study examined the effects of mulberry fruit on the antioxidative defense systems and oxidative stress in the erythrocytes of diabetes-induced rats. Sprague-Dawley male rats were randomly assigned to one normal and three streptozotocin (STZ)-induced diabetic groups. 1be diabetic groups were fed a mulberry fruit-free diet (DM-group), 0.3% mulberry fruit diet (DM-F group) or 0.6% mulberry fruit diet (DM-2F group). Diabetes was induced with STZ after three weeks of the experimental diets. 1be rats were sacrificed 9 days later for examination of the antioxidative defense systems and oxidative stress in the erythrocytes. Means of cy-3-Ο-glucopyranoside, cy-3-Ο-rutinoside, rutin, isoquercitrin, quercetin, morin and dehydroquercetin contents were 230.45, 131.5, 142.5, 10.3, 5.8, 1.6 and 3.83mg per l00g dry weight, respectively, in the mulberry fruit. Mulberry fruit strengthened the antioxidative defense systems through increased activity of the antioxidant enzymes, such as glutathione peroxidase (GSH-px) and catalase (CAT), in the erythrocytes of the diabetes-induced rats. Accrdingly, mulberry fruit was found to reduce the accumulation of thiobarbituric acid reactive substance (WARS). Therefore, mulberry fruit was found to be excellent for strengthening the antioxidative defense system and reducing damaging oxidative substances in the erythrocytes of the diabetes-induced rats.

• 한국약용작물학회지
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• 제15권2호
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• pp.132-137
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• 2007

Inhibitory effect of Scutellaria baicalensis ethanol extracts (SR) on chemical mediator release and immunoglobulin (Ig) production from Sprague-Dawley rats originated cells as type I allergic reaction was examined. SR showed concentration-dependent inhibition on basal and concanavalin A (ConA)-stimulated Ig production. In the mesenteric lymph node lymphocytes, the inhibitory effect of SR on the IgE production in the presence of Con A was stronger than these on IgA and IgG production. Moreover, tumor necrosis factor-alpha $(TNF-{\alpha})$ production-inhibiting effect of SR in the presence ConA was observed. However, SR did not affect the production of $interferon-{\gamma}$. SR also inhibited histamine release from the peritoneal exudate cells stimulated with a calcium ionophore A23187. In the case of leukotriene B4, SR markedly inhibited it at the concentration of 100 mg/ml. From these results, ethanol extracts obtained from Scutellaria baicalensis may have an anti-allergic effect on the intestinal system of rats.

• KSBB Journal
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• 제32권2호
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• pp.124-132
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• 2017

A methane-oxidizing bacterium was isolated from rice paddy field soil around Jeollanam-do province, Korea, and characterized. The isolate was gram-negative, orange pigmented and short rod ($1.1-1.2{\times}1.6-1.9{\mu}m$). It was catalase and urease-negative but oxidase-positive. The strain utilized methane and methanol as sole carbon and energy sources. It had an ability to grow with an optimum pH 7.0 and an optimum growth temperature $30^{\circ}C$. The strain was resistant to antibiotic polymyxin B but sensitive to streptomycin, kanamycin, ampicillin, chloramphenicol and rifampicin. The isolate required copper for their growth with concentration range of $2-25{\mu}M$, with an optimum of $10{\mu}M$. Under optimal culture condition, specific cell growth rate and generation time were found to be $0.046hr^{-1}$ and 15.13 hr, respectively. Phylogenetic analysis based on 16S rDNA sequences indicated that the strain formed a tight phylogenetic lineage with Methylomonas koyamae with a value of 99.4% gene sequence homology. So, we named the isolate as Methylomonas sp. SM4. 8.6 mM methanol was accumulated in the reaction mixture containing 70 mM sodium formate and 40 mM $MgCl_2$ (MDH inhibitor) under atmosphere of methane:air (40:60) mixture for 24 hr at $30^{\circ}C$.

• 한국환경과학회지
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• 제21권9호
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• pp.1079-1085
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• 2012

Ground seawater quality was investigated, and the algal growth potential (AGP) tests were performed along the Tongyeong coast to examine the inflow of materials, which is needed for the red tide species Cochlodinium polykrikoides to grow. The study was conducted to determine the mechanism for C. polykrikoidesred tides. Water temperature, salinity, pH, and dissolved oxygen (DO) ranged from 16.05 to $20.74^{\circ}C$, 18.20 to 32.11 psu, 6.00 to 7.61, and 3.41 to 7.91 mg/L (41.4-96.1%), respectively. No seasonal variation was observed in water temperature. The salinity, pH, and DO saturations at most stations were lower than those of coastal seawater at Tongyeong. The ${NH_4}^+$-N, ${NO_{2+3}}^-$-N, ${PO_4}^{3-}$-P concentrations ranged from 0.43 to 16.00 ${\mu}M$, 1.50 to 132.38 ${\mu}M$, and 1.30 to 6.29 ${\mu}M$, respectively; the values at some stations were much higher than observed in Tongyeong coast seawater. Using seawater from station B, C. polykrikoides grew consistently, with a high growth rate, similar to the red tide in nature. This seawater appeared to contain materials needed by C. polykrikoides to grow. Therefore, C. polykrikoides red tides seem to occur wherever the ground sea water contains materials that are needed for its growth.