• IMMUNE NETWORK
• /
• v.20 no.4
• /
• pp.35.1-35.13
• /
• 2020

Antigen delivery systems play critical roles in determining the quality and quantity of Ab responses in vivo. Induction of protective antibodies by B cells is essential in the development of vaccines against infectious pathogens, whereas production of IgE antibodies is prerequisite for investigation of allergic responses, or type 1 hypersensitivity reactions. Virus-like particles (VLPs) are efficient platforms for expression of proteins of interest in highly repetitive manners, which grants strong Ab responses to target antigens. Here, we report that delivery of hen egg lysozyme (HEL), a model allergen, through VLP could provoke strong HEL specific IgE Ab responses in mice. Moreover, acute allergic responses were robustly induced in the mice sensitized with VLPs that express HEL, when challenged with recombinant HEL protein. Our data show that antigen delivery in the context of VLPs could function as a platform for sensitization of mice and for subsequent examination of allergic reactions to molecules of interest.

• Applied Chemistry for Engineering
• /
• v.29 no.4
• /
• pp.369-375
• /
• 2018

Batch experiments were conducted to investigate the effects of operating parameters such as the temperature, initial concentration, contact time and adsorbent dosage on the adsorption of antibiotics amoxicillin (AMX) by waste citrus peel based activated carbon (WCAC). The kinetics and isotherm experiment data can be well described with the pseudo-second order model and the Langmuir isotherm model, respectively. The maximum adsorption capacity of AMX by WCAC calculated from the Langmuir isotherm model was 125 mg/g. The adsorption of AMX by WCAC shows that the film diffusion (external mass transfer) and the intraparticle diffusion occur simultaneously during the adsorption process. The adsorption rate is more influenced by the intraparticle diffusion than that of the external mass transfer as the particle size of WCAC increases, and the intraparticle diffusion is the rate controlling step. The thermodynamic parameters indicated that the adsorption reaction of AMX by WCAC was an endothermic and spontaneous process.

• Journal of Veterinary Science
• /
• v.22 no.6
• /
• pp.76.1-76.15
• /
• 2021

Background: The development of a vaccine for Jembrana disease is needed to prevent losses in Indonesia's Bali cattle industry. A DNA vaccine model (pEGFP-C1-tat) that requires a functional delivery system will be developed. Polylactic-co-glycolic acid (PLGA) may have potential as a delivery system for the vaccine model. Objectives: This study aims to evaluate the in vitro potential of PLGA as a delivery system for pEGFP-C1-tat. Methods: Consensus and codon optimization for the tat gene was completed using a bioinformatic method, and the product was inserted into a pEGFP-C1 vector. Cloning of the pEGFP-C1-tat was successfully performed, and polymerase chain reaction (PCR) and restriction analysis confirmed DNA isolation. PLGA-pEGFP-C1-tat solutions were prepared for encapsulated formulation testing, physicochemical characterization, stability testing with DNase I, and cytotoxicity testing. The PLGA-pEGFP-C1-tat solutions were transfected in HeLa cells, and gene expression was observed by fluorescent microscopy and real-time PCR. Results: The successful acquisition of transformant bacteria was confirmed by PCR. The PLGA:DNA:polyvinyl alcohol ratio formulation with optimal encapsulation was 4%:0.5%:2%, physicochemical characterization of PLGA revealed a polydispersity index value of 0.246, a particle size of 925 nm, and a zeta potential value of -2.31 mV. PLGA succeeded in protecting pEGFP-C1-tat from enzymatic degradation, and the percentage viability from the cytotoxicity test of PLGA-pEGFP-C1-tat was 98.03%. The PLGA-pEGFP-C1-tat demonstrated luminescence of the EGFP-tat fusion protein and mRNA transcription was detected. Conclusions: PLGA has good potential as a delivery system for pEGFP-C1-tat.

• Journal of Korean Society for Atmospheric Environment
• /
• v.26 no.5
• /
• pp.475-489
• /
• 2010

In order to verify the enhancement of ozone and carbon monoxide (CO) during springtime in East Asia, we investigated weather conditions and data from remote sensors, air quality models, and air quality monitors. These include the geopotential height archived from the final (FNL) meteorological field, the potential vorticity and the wind velocity simulated by the Meteorological Mesoscale Model 5 (MM5), the back trajectory estimated by the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model, the total column amount of ozone and the aerosol index retrieved from the Total Ozone Mapping Spectrometer (TOMS), the total column density of CO retrieved from the Measurement of Pollution in the Troposphere (MOPITT), and the concentration of ozone and CO simulated by the Model for Ozone and Related Chemical Tracers (MOZART). In particular, the total column density of CO, which mightoriginate from the combustion of fossil fuels and the burning of biomass in China, increased in East Asia during spring 2000. In addition, the enhancement of total column amounts of ozone and CO appeared to be associated with both the upper cut-off low near 500 hPa and the frontogenesis of a surface cyclone during a weak Asian dust event. At the same time, high concentrations of ozone and CO on the Earth's surface were shown at the Seoul air quality monitoring site, located at the surface frontogenesis in Korea. It was clear that the ozone was invaded by the downward stretched vortex anomalies, which included the ozone-rich airflow, during movement and development of the cut-off low, and then there was the catalytic photochemical reaction of ozone precursors on the Earth's surface during the day. In addition, air pollutants such as CO and aerosol were tracked along both the cyclone vortex and the strong westerly as shown at the back trajectory in Seoul and Busan, respectively. Consequently, the maxima of ozone and CO between the two areas showed up differently because of the time lag between those gases, including their catalytic photochemical reactions together with the invasion from the upper troposphere, as well as the path of their transport from China during the weak Asian dust event.

• Journal of Environmental Science International
• /
• v.11 no.5
• /
• pp.419-436
• /
• 2002

The current paper reports on the enhancement of O$_3$, CO, NO$_2$, and aerosols during the Asian dust event that occurred over Korea on 1 May 1999. To confirm the origin and net flux of the O$_3$, CO, NO$_2$, and aerosols, the meteorological parameters of the weather conditions were investigated using Mesoscale Meteorological Model 5(MM5) and the TOMS total ozone and aerosol index, the back trajectory was identified using the Hybrid Single-Particle Lagrangian Integrated Trajectory Model(HYSPLIT), and the ozone and ozone precursor concentrations were determined using the Urban Ashed Model(UAM). In the presence of sufficiently large concentrations of NO$\sub$x/, the oxidation of CO led to O$_3$ formation with OH, HO$_2$, NO, and NO$_2$ acting as catalysts. The sudden enhancement of O$_3$, CO, NO$_2$ and aerosols was also found to be associated with a deepening cut-off low connected with a surface cyclone and surface anticyclone located to the south of Korea during the Asian dust event. The wave pattern of the upper trough/cut-off low and total ozone level remained stationary when they came into contact with a surface cyclone during the Asian dust event. A typical example of a stratosphere-troposphere exchange(STE) of ozone was demonstrated by tropopause folding due to the jet stream. As such, the secondary maxima of ozone above 80 ppbv that occurred at night in Busan, Korea on 1 May 2001 were considered to result from vertical mixing and advection from a free troposphere-boundary layer exchange in connection with an STE in the upper troposphere. Whereas the sudden enhancement of ozone above 100 ppbv during the day was explained by the catalytic reaction of ozone precursors and transport of ozone from a slow-moving anticyclone area that included a high level of ozone and its precursors coming from China to the south of Korea. The aerosols identified in the free troposphere over Busan, Korea on 1 May 1999 originated from the Taklamakan and Gobi deserts across the Yellow River. In particular, the 1000m profile indicated that the source of the air parcels was from an anticyclone located to the south of Korea. The net flux due to the first invasion of ozone between 0000 LST and 0600 LST on 1 May 1999 agreed with the observed ground-based background concentration of ozone. From 0600 LST to 1200 LST, the net flux of the second invasion of ozone was twice as much as the day before. In this case, a change in the horizontal wind direction may have been responsible for the ozone increase.

• Resources Recycling
• /
• v.32 no.2
• /
• pp.33-42
• /
• 2023

Metal emulsions have been studied for several decades as a method of increasing the efficiency of the steelmaking process. This study was performed using a water model, observable at room temperature, to compensate for the disadvantages of the high-temperature experiment, the results of which are difficult to observe visually. As a substitute for metal-in-slag emulsions, experiments were conducted by dropping distilled water into silicone oil and comparing the results with the results of a calculation by momentum balance equations. The descending velocity of the water droplet decreased as the diameter of the droplet and viscosity of the fluid (silicon oil) increased. To simulate the descending velocity of a water droplet in silicon oil under stirring conditions, the flow rate of the fluid (silicon oil) was measured by particle image velocimetry (PIV) methods. The calculation of the descending velocity of the water droplet was in good agreement with the measured values, with and without stirring a viscous silicone oil.

• Korean Chemical Engineering Research
• /
• v.43 no.2
• /
• pp.206-214
• /
• 2005

Heterogeneously-catalyzed oxidation of aqueous phase trichloroethylene (TCE) over supported metal oxides has been conducted to establish an approach to eliminate ppm levels of organic compounds in water. A continuous flow reactor system was designed to effect predominant reaction parameters in determining catalytic activity of the catalysts for wet TCE decomposition as a model reaction. 5 wt.% $CoO_x/TiO_2$ catalyst exhibited a transient period in activity vs. on-stream time behavior, suggesting that the surface structure of the $CoO_x$ might be altered with on-stream hours; regardless, it is probable to be the most promising catalyst. Not only could the bare support be inactive for the wet decomposition reaction at $36^{\circ}C$, but no TCE removal also occurred by the process of adsorption on $TiO_2$ surface. The catalytic activity was independent of all particle sizes used, thereby representing no mass transfer limitation in intraparticle diffusion. Very low TCE conversion appeared for $TiO_2$-supported $NiO_x$ and $CrO_x$ catalysts. Wet oxidation performance of supported Cu and Fe catalysts, obtained through an incipient wetness and ion exchange technique, was dependent primarily on the kinds of the metal oxides, in addition to the acidic solid supports and the preparation routes. 5 wt.% $FeO_x/TiO_2$ catalyst gave no activity in the oxidation reaction at $36^{\circ}C$, while 1.2 wt.% Fe-MFI was active for the wet decomposition depending on time on-stream. The noticeable difference in activity of the both catalysts suggests that the Fe oxidation states involved to catalytic redox cycle during the course of reaction play a significant role in catalyzing the wet decomposition as well as in maintaining the time on-stream activity. Based on the results of different $CoO_x$ loadings and reaction temperatures for the decomposition reaction at $36^{\circ}C$ with $CoO_x/TiO_2$, the catalyst possessed an optimal $CoO_x$ amount at which higher reaction temperatures facilitated the catalytic TCE conversion. Small amounts of the active ingredient could be dissolved by acidic leaching but such a process gave no appreciable activity loss of the $CoO_x$ catalyst.

• Applied Chemistry for Engineering
• /
• v.32 no.5
• /
• pp.562-568
• /
• 2021

An O/W (oil in water) emulsion, wheat germ oil raw material, was produced by using natural wheat germ oil and composite sugar-ester. The effects of variables such as the hydrophile-lipophile balance (HLB) value, added emulsifier amount, and emulsification time on the average particle size, emulsification viscosity and ESI of O/W wheat germ oil emulsion were investigated. The parameters of the emulsification process produced by the central composite design model of the response surface methodology (CCD-RSM), which is a reaction surface analysis method, were simulated and optimized. The optimum process conditions obtained from this paper for the production of O/W wheat germ oil emulsion were 8.4, 6.4 wt%, 25.4 min for the HLB value, amount of emulsifier, and emulsion time, respectively. The predicted reaction values by CCD-RSM model under the optimum conditions were 206 nm, 8125 cP, and 98.2% for mean droplet size (MDS), viscosity, and ESI, respectively, based on the emulsion after 7 days. The MDS, viscosity and ESI of the emulsion obtained from actual experiments were 209 nm, 7974 cP and 98.7%, respectively. Therefore, it was possible to design an optimization process for evaluating the stability of the emulsion of wheat germ oil raw material by CCD-RSM.

• Korean Journal of Food Science and Technology
• /
• v.30 no.2
• /
• pp.425-433
• /
• 1998

The characteristics of the reaction of calcium carbonate $(CaCO_3)$ immobilized with alginate as buffer system for the high concentration cultivation of bifidobacteria in fermenter are described by the mathematical model, and tested for the reusing possibility of the used $CaCO_3$ beads. When$CaCO_3$ beads with the various diameters were reacted in 0.1 M of the mixed organic acids (0.6 M of acetic acid and 0.4 M lactic acid) and in fermenter inoculated Bifidobacterium longum ATCC 15707, the change of bead diameters can be calculated with the amount of the decreased $CaCO_3$ from the surface of bead using the mathematical model. These values was similar to the directly measured bead diameter by a micrometer. Therefore, it was considered that the mathematical model could be used for explaining the reaction charateristics of the $CaCO_3$ bead reacted with the organic acids. When Bifidobacterium longum was incubated at $37^{\circ}C$ for 20 hours in fermenter with $CaCO_3$ beads, the buffering effect of $CaCO_3$, the reduce rate of the bead diameter, and the growth rate of Bifidobacterium longum were higher at the smaller beads than beads with the larger diameters. Also, when Bifidobacterium longum was incubated in fermenter with the mixed beads which were added new beads to the recovered beads in order to equalize with the total surface area of initial beads, the buffering effect of $CaCO_3$ bead and the growth rate of Bifidobacterium longum were very corresponded with the results of the fermentation using the only initial beads. Therfore, it is expected that the used beads can be reused by adding the initial beads.

• Journal of Microbiology
• /
• v.40 no.4
• /
• pp.313-318
• /
• 2002

To perform the prophylactic study of a vaccine derived from human papillomavirus (HPV) using Balb/c mice, we produced virus like particles consisting of HPV capsid protein L1 which has been reported to induce significant humoral and cellular immunity using various animal model systems. In order to produce HPV16 VLPs, the cDNA of L1 capsid protein in HPV type 16, obtained by polymerase chain reaction, was inserted into yeast expression vector, YEG$\alpha$-HIR525 under the control of GAL10 promoter. The transformation of YEG$\alpha$-HPV16 L1 was performed into the yeast Saccharomyces cerevisiae Y2805 by the lithium acetate method and the yeast clone expressing the highest level of L1 capsid protein of human papillomavirus type 16 was selected by Western blot analysis using anti-HPV16 L1 antibody. The purification of HPV16 VLP has been performed by the ultracentrifugation and gel-filtration methods. To validate the vaccine efficacy of the purified HPV16 VLPs and investigate the properties of HPV16 VLPs to induce humoral immunity, ELISA assay was performed. A significantly increased production of anti-HPV16 VLP antibodies was observed in sera from immunized mice. The neutralization activity of antibodies in the sera from the vaccinated mice was demonstrated by a rapid and simple assay to detect hemagglutihation inhibition activity.