• Journal of Pharmaceutical Investigation
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• v.32 no.2
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• pp.73-80
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• 2002

Cefuroxime axetil is a cephalosporin antibiotic having a high activity against a wide spectrum of Grampositive and Gram-negative microorganisms. It is a cephalosporin antibiotic which exist as 2 diastereoisomers: diastereoisomer A and B. It shows polymorphism of three forms: a crystalline form having a melting point of about $180^{\circ}C$, a substantially amorphous form having a high melting point of about $135^{\circ}C$ and a substantially amorphous form having a low melting point of about 70^{\circ}C$. The crystalline form of cefuroxime axetil is slightly soluble in water because diastereoisomer A has lower solubility than B in water. Substantially amorphous form of which there are no difference in solubility between diastereoisomer A and B has better solubility than crystalline form, but it forms a thicker gel than crystalline form upon contact with an aqueous medium. Based on this reason, cefuroxime axetil is not readily absorbable in the gastrointestinal tract, rendering its bioavailability on oral administration very low. The object of this study was to develop an improved non-crystalline cefuroxime axetil composition having a high physicochemical stability and bioavailability. A non-crystalline cefuroxime axetil solid dispersant showing no peak on a Differential Scanning Calorimetry (DSC) scan is prepared by dissolving cefuroxime axetil and a surfactant in an organic solvent; suspending a water-insoluble inorganic carrier in the resulting solution; and spray drying the resulting suspension to remove the organic solvent, said solid dispersant having an enhanced dissolution and stability of cefuroxime axetil and being useful for the preparation of a pharmaceutical composition for oral administration. Tablet was formulated with this cefuroxime axetil solid dispersant, disintegrants and other ingredients. It disintegrated and dissolved easily and dynamically in dissolution medium, so showed a good dissolution profile.

• Applied Biological Chemistry
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• v.38 no.1
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• pp.26-30
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• 1995

To produce ethanol from Jerusalem artichoke powder efficiently, Kluyveromyces marxianus FO43 cells were encapsulated in 2% sodium alginate and were cultured in batch reactor to investigate the fermentation properties. Batch culture of immobilized cells left for 4 days in 15% Jerusalem artichoke medium showed ethanol concentration of 3.38%(w/v) and ethanol yield to theoretical value of 54.20%, lower than 3.76%(w/v) and 71.13% for the culture of free cells. Addition of cellulase to $15{\sim}20%$ Jerusalem artichoke media increased the production of ethanol, owing to remarkable reduction in consistency of the suspension. So it was possible to achieve an ethanol concentration of 5.57%(w/v) arid an ethanol yield to theoretical value of 68.86% in even 20% Jerusalem artichoke medium by cultivation of immobilized cells for 4 days. The alginate beads showed constant ethanol productivity after recycling 11 times (22 days) in repeated batch fermentation.

• Korean Journal of Plant Tissue Culture
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• v.27 no.2
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• pp.133-136
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• 2000

To evaluate the biological effects of dykellic acid, a novel apoptosis inhibitor, isolated from microorganism on the plant cells, the cell growth, protein contents, and superoxide dismutase (SOD) activity were investigated in suspension cultures of tobacco photomixotrophic cultured (PM) cells on 12 days after different concentration of chemical treatment. The cells were cultured in MS medium containing 0.7 mg/L 2,4-D, 0.3 mg/L kinetin, 30 g/L sucrose and 200 mM NaCl at $25^{\circ}C$ in the light (100 rpm). Dykellic acid strongly inhibited the cell growth by evaluating the cell fresh wt and the ion conductivity in the medium ($IC_{50}$/, about 20 $\mu$M). The results as inhibition of cell growth and cell wall damage were same. The compound significantly increased the protein contents and the SOD specific activity in proportion with the dosage. The results suggested that dykellic acid may have biological activity in plant cells and tobacco PM cells may be suitable biomaterials for in vitro evaluation of the biological activity of natural products.

• Restorative Dentistry and Endodontics
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• v.22 no.1
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• pp.374-387
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• 1997

The purpose of this study was to examine the distribution of lymphocyte populations in normal, reversibly inflamed and irreversibly inflamed human dental pulp tissues using flow cytometry. Flow cytometry, with specific antibody and fluorochrome reagent allows us to know cellular properties of hematolymphoid cells by measuring fluorescence of stained cells. Before extirpation of pulps in routine endodontic treatment, the clinical diagnosis were performed by symptom. The extirpated pulp tissues were divided into normal pulp group (N=5), reversible pulpit is group(N=10) and irreversible pulpitis group(N=7). The specimen was placed into RPMI 1640 medium, minced into small pieces, and then digested in medium with collagenase. The cell suspension was resuspended in PBS for monoclonal antibody staining of T lymhocytes(CD3+), B lymphocytes (CD19+), T helper cell (CD4+) and T supressor cell (CD8+). The percentages of cells were counted by FACStar(BD) flow cytometer. Following results were obtained; 1. In the most normal and inflamed pulps, the percentages of T lymphocyte, B lymphocytes, T helper cell and T suppressor/cytotoxic cell were less than 1 % in total counted pulpal cells. 2. The higher percentages of T, B, T helper and T suppressor cells were observed in irreversible pulpitis group as compared with the normal pulp and reversible pulpitis group but the differences between groups were not statistically significant (p>0.05). 3. The percentages of T helper cells (CD4 + cells) were greater than that of T suppressor/cytotoxic cells (CD8 + cells) in the inflamed pulps.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.154-163
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• 2009

The groutability depends on the properties of the grout, its injection processes, and on the mechanical properties of the soil formation. During the process of pouring cement-based grouting into a porous medium, a variation with time occurs in the viscosity of grout suspension. In addition the particle filtration phenomenon will limit the expansion of the grouted zone because cement particles are progressively stagnant within the soil matrix. In this paper, a closed-form solution was derived by implementing the mass balance equations and the generalized phenomenological filtration law, which can be used to evaluate the deposition of cement-based grout in the soil matrix. The closed-form solution relevant to a particular spherical flow was modified by a step-wise numerical calculation, considering the variable viscosity caused by a chemical reaction, and the decrease in porosity resulting from grout particle deposition in the soil pores. A series of pilot-scale chamber injection tests was performed to verify that the developed step-wise numerical calculation is able to evaluate the injectable volume of grout and the deposition of grout particles. The results of the chamber injection tests concurred well with that of the step-wise numerical calculation. Based on the filtration phenomenon, a new groutability criterion of cement-based grout in a porous medium was proposed, which might facilitate a new insight in the design of the grouting process.

• Journal of Plant Biotechnology
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• v.32 no.2
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• pp.135-138
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• 2005

Embryogenic callus was obtained from cotyledonary explants of Codonopsis lanceloata on Murashige & Skoog's medium supplemented with 1 mg/L 2,4-D. Suspension cultures of the embryogenic calli were grown on a shaker at 100 strokes/min, and then the calli were subcultured for 2 weeks in 2,4-D-free medium to produce somatic embryo. In somatic embryos at the globular stage, cotyledon initials began to differentiate themselves in the near distal end of the procambial strand. Dicotyledons, tricotyledon, tetracotyledon and fused cotyledon were differentiated from the distal ends of two, three, four and circular procambial strands, respectively. Nearly circular procambial strand in lower hypocotyls were independently differentiated into two, three, four procambial tissues at cotyledonary node and cotyledons to form somatic embryos with dicotyledon, tricotyledon, tetracotyledon. If the distal subepidermal cells of globular embryo exclusively became cotyledon initials, the torpedo or cotyledonary embryo was characterized by somatic embryos with fused cotyledon.

• KSBB Journal
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• v.10 no.4
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• pp.435-440
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• 1995

During culture the effect of polyamine on hairy root of Buplerum falcatum by infection of Agrobacterium rhizogenes was studied. The fresh and dry weight of hairy root which cultured for 3months in MS medium increased about 7-fold when spermine at 10${\mu}$M, 100${\mu}$M was treated. After suspension culture of B. falcatum in MS medium containing putrescine(10${\mu}$M, 100${\mu}$M) or spermine(10${\mu}$M), the contents of endogenous polyamine (putresclne, spermidine, spermine) was higher than that of control. The ${\beta}$-glucan synthetase II activity by polyamine treatment was increased： especially spermidine (100${\mu}$M) and spermine(100${\mu}$M) stimulated it by about 180% and 220% respectively. These results suggest a possible role of polyamine as growth regulator in B. falcatum hairy root cultures.

• Korean Journal of Materials Research
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• v.11 no.2
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• pp.137-145
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• 2001

A new process, gelcasting in aqueous medium, to fabricate complex-shaped ceramic core has investigated. The ceramic slurry, mixture of fused silica powder and additives such as zircon and cordierite, was electrosterically stabilizes. The slip was prepared by ball milling of polydispered ceramic suspension with monomer, dimer and dispersant. The rheological behavior of slip was evaluated by viscosity measurement. It was found that the high solid loading of polydispersed ceramic slip, which has low viscosity of 50vol%, is possible to obtained. The viscosity of the slip was significantly dependent upon the amount of polymer dispersant and the formulation of monomer and dimer. The green bodies were fabricated through casting and gelation at room temperature followed by drying at $25^{\circ}C$ for 48hrs under relative humidity of 80~85%. Crack-free green body was successfully fabricated through the above process.

• Korean Journal of Animal Reproduction
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• v.14 no.1
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• pp.1-8
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• 1990

These experiments were carried out to investigate the effects of cumulus cells for in vitro fertilization and development of bovine follicular oocytes matured in vitro. The bovine ovaries were obtained at a slaughter house and the follicular oocytes surrounded by cumulus cells were collected by puncturing follicles with 2~6 mm of diameter. Bovine oocytes were matured in vitro for 24~26 hours in a CO2 incubator with 5% CO2 in air at 39$^{\circ}C$. The medium used for maturation was TCM-199 supplemented with hormones, pyruvate, FCS and antibiotics. Epididymal spermatozoa were capacitated by in vitro culture for 2~3 hours in BO solution containing BSA(5mg/ml) and caffeine(2.5mM). Insemination was made by introducing about 10~15 matured oocytes into the suspension of capacitated spermatozoa. Six hour after insemination the eggs were transferred to TCM-199 supplemented with FCS(10%) and HEPES(25mM), cultured for 7~8 days with 10~15 eggs/well in 4-well multidishes(Nunc Co.) forming cumulus cell monolayer. The results obtained in these experiments were summarized as follows ; 1. The majority of the follicular oocytes with compacted cumulus cells existed in GV stage while those with dispersed or denuded cumulus cells existed GVBD and M II stage. 2. After 24~26 hours maturation, the maturation rates of the follicular oocytes cultured in TCM-199 containing hormones were slightly higher than those of oocytes cultured in medium without hormones, and the frequency of cumulus compacted or denuded oocytes reaching M II stage cultured in medium containing hormones was 75.7% or 51.7%, respectively(P<0.05). 3. After 20 hours in vitro insemination, percentages of ova fertilized were 61.4% or 51.4%, respectively, for cumulus oophorus intacted or removed, and increased frequency of ova with both male and female pronuclei was found when cumuli were present(P<0.05). 4. The rates of embryos developed to 2-, 4-, 8-, 16-cell and morula or blastocyst stage after cocultured with cumulus cells were 65.0%, 45.3%, 34.7%, 28.0% and 22.7%, respectively. The results for momla or blastocyst stage were significantly higher than those of the embryos cultured in the basic medium(P<0.05).

• Korean Journal of Plant Tissue Culture
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• v.28 no.3
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• pp.159-164
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• 2001

To produce novel bioactive flavonoids, Gericudranin A and Gericudranin B, a cell culture system of Cudrania tricuspidata including callus induction and optimization of culture conditions was established. Friable calli were efficiently induced from the hypocotyl segments of seedlings on B5 medium supplemented with 1.0 mg/L NAA, 0.1 mg/L kinetin and 3% sucrose. Several factors were optimized for the Gericudranin production and the cell growth in suspension cultures. Low level of basal salt medium (1/8 MS), 1.0 mg/L IAA and 0.1 mg/L zeatin, and high level of sucrose (5%) were effective for the production of Gericudranins, whereas WPM with 1.0 mg/L NAA, 0.1 mg/L zeatin, and 5% sucrose were more effective for the cell growth. When cells were cultured on MS liquid medium supplemented with 1.0 mg/L IBA, about 2200 $\mu\textrm{g}$/g dry wt of Gericudranin A could be produced. The level might be about 10 times of the native inner bark. About 2350 $\mu\textrm{g}$/g dry wt of Gericudranin B was also produced on MS liquid medium with 5% sucrose, 1.0 mg/L NAA, 0.1 mg/L kinetin. The content was estimated about 3 times of the level of native inner bark.