• Journal of Microbiology and Biotechnology
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• v.21 no.2
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• pp.170-175
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• 2011

This study was carried out for the molecular level identification of recombinant protein vaccine efficacy, by oral feeding against white spot syndrome virus infection, with the comparison of viral mRNA transcriptional levels in shrimp cells. For the determination of WSSV dilution ratio for the vaccination experiment by oral feeding, in vivo virus titration was carried out using different virus dilutions of virus stock ($1{\times}10^2$, $2{\times}10^2$, and $1{\times}10^3$). Among the dilution ratios, $2{\times}10^2$ diluted WSSV stock was chosen as the optimal condition because this dilution showed 90% mortality at 10 days after virus injection. Recombinant viral proteins, rVP19 and rVP28, produced as protein vaccines were delivered in shrimps by oral feeding. The cumulative mortalities of the shrimps vaccinated with rVP19 and rVP28 at 21 days after the challenge with WSSV were 66.7% and 41.7%, respectively. This indicates that rVP28 showed a better protective effect against WSSV in shrimp than rVP19. Through the comparison of mRNA transcriptional levels of viral genes from collected shrimp organ samples, it was confirmed that viral gene transcriptions of vaccinated shrimps were delayed for 4~10 days compared with those of unvaccinated shrimps. Protection from WSSV infection in shrimp by the vaccination with recombinant viral proteins could be accomplished by the prevention of entry of WSSV due to the shrimp immune system activated by recombinant protein vaccines.

• Journal of Microbiology and Biotechnology
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• v.14 no.1
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• pp.35-40
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• 2004

Rotavirus virus-like particle (VLP) composed of VP2, VP6, and VP7 was expressed in the Baculovirus Expression Vector System (BEVS). Sf9 cell, a host of the baculovirus, was cultured from a 0.5-1 spinner flask to the 50-1 bioreactor system. Sf9 cell was maintained at cell density between 3.0E＋05 and 3.0E＋06 cells/ml and grew up to 1.12E＋07 cells/ml in the bioreactor. Growth kinetics was compared under different culture systems and showed similar growth kinetics with 20.1-25.2 h of doubling time. Early exponentially growing cell culture was infected with three recombinant baculoviruses expressing VP2, VP6, and VP7 protein at 1.0, 2.0, and 0.2 moi, respectively. The expression of rotavirus proteins was confirmed by Western blot analysis and its three-layered virus-like structure was observed under an electron microscope. Rotavirus VLP was semipurified and immunized in ICR mice intramuscularly. Rotavirus-specific serum antibody was detected from 2 weeks after the immunization and lasted at least 21 weeks of the post-immunization, indicating its possible use as a vaccine candidate.

• Food Science of Animal Resources
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• v.33 no.1
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• pp.58-66
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• 2013

In this study, the effect of packaging methods [aerobic packaging (AP), vacuum packaging (VP) and modified atmosphere packaging (MAP: 75% $N_2$, 25% $CO_2$)] on colour, lipid quality and microbial growth of beef patties enhanced with flaxseed flour was investigated during storage at $2{\pm}1^{\circ}C$ for 10 d. L and a values of beef patties packaged in MAP and VP were higher (p<0.05) than that of the samples packaged in AP. Packaging in MAP and VP retarded the lipid oxidation (TBA value) and inhibited the bacterial growth of beef patties enhanced with flaxseed flour. Furthermore, TBA values in beef patties were correlated with a values (r = -0.340; p<0.05). Packaging in MAP was more effective than packaging in VP for inhibiting microbial growth. The samples packaged in VP lost their shape due to the compression by external atmosphere. Packaging treatment had no significant effect on saturated fatty acid (SFA), monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) levels in beef patties. The a and b, TBA and MUFA values changed during storage time. TBA values for beef patties increased during storage time, but did not reach to the limit value (1 mg/kg) until the end of the storage time. The results suggest that the shelf life of beef patties enhanced with flaxseed flour can be extended by packaging in MAP.

• Restorative Dentistry and Endodontics
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• v.33 no.2
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• pp.107-114
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• 2008

This study was performed to assess the radiopacity of a variety of canal filling and retrograde root-end filling materials according to the specification concerning root canal obturation materials. Ten materials including Gutta-percha pellets, amalgam, Fuji II LC, $Dyract^{(R)}$ AP, Super $EBA^{(R)}$, $IRM^{(R)}$, AH $26^{(R)}$, $Sealapex^{TM}$, Tubli-$Seal^{TM}$, and dentin were evaluated in this study. In the first part, densitometric reading of an each step of aluminum step wedge on occlusal film were performed at 60 kVp (0.2, 0.3, 0.4 s), 70 kVp (0.2, 0.3, 0.33 s) to decide appropriate voltage and exposure time. In the second part, ten specimens which are 5 mm in diameter and 0.5, 1.0, 1.5, 2.0, 2.5, 3.0 mm in thickness, were fabricated from each material studied. The specimens were radiographed simultaneously with an aluminum step wedge under decided condition (60 kVp, 0.2 s). The mean radiographic density values of the materials were transformed into radiopacity expressed equivalent thickness of aluminum (mm Al). The following results were obtained. 1. Among the various conditions including 0.2 s, 0.3 s, 0.4 s at 60 kVp and 0.2 s, 0.3 s, 0.33 s at 70 kVp, the appropriate voltage and exposure time that meet the requirement of density from 0.5 to 2.0 was 0.2 s at 60 kVp. 2. All of the materials in this study had greater radiopacity than the minimun level recommended by ISO No. 4049 standards. 3. Most of the materials had greater radiopacity than 3 mm Al requirement of ANSI/ADA specification No. 57 (2000) and ISO No. 6876 (2001) standards except for Fuji II LC and Dyract. It suggests that all experimental canal filling and retrograde root-end filling materials have a sufficient radiopacity that meet the requirement concerning root canal obturation materials except for Fuji II LC and Dyract.

• Journal of Plant Biotechnology
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• v.29 no.2
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• pp.93-98
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• 2002

A VP6 fragments was subcloned with BamHI in the binary pMBP-1 vector under Califlower Mosaic Virus (CaMV) 355 promoter and neomycin phosphotransferase II (npt II) gene. The recombinant binary vector was mobilized into Agrobacterium-tumefaciens LBA4404 by the freeze-thaw method and potato (Solanum tubensum L. cv Desiree) was transformed by modified leaf-disc cocultivation. Shoots were induced on MS medium with 0.01 mg/L NAA, 0.1 mg/L GA$_3$, 2.0 mg/L Zeatin, 100.0 mg/L kanamycin, 500.0 mg/L carbenicillin. In order to identify the copy number of VP6 into potato plant, total genomic DNA was isolated from transgenic potato and analysed by Southern blotting. Genomic DNA and total mRNA analysis demonstrated the incorporation of the foreign gene into the potato genome, as well as their transcription.

• Fisheries and Aquatic Sciences
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• v.26 no.3
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• pp.204-215
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• 2023

The thermolabile haemolysin (tlh) of Vibrio parahaemolyticus (Vptlh) from V. parahaemolyticus is a multiple-function enzyme, initially describes as a haemolytic factor activated by lecithin and phospholipase A2 enzymatic activity (Shinoda, 1991; Vazquez-Morado, 2021; Yanagase et al., 1970). Until now, the tlh structure has hypothesized including N-terminal and C-terminal domain, but what domain of the Vptlh structure does the haemolytic activity has not been refined yet. In this study, a 450-bp VpTLH nucleotide sequence of the entire Vptlh gene encoded the C-terminal domain cloned firstly to examine its responsibility in the activity of the Vptlh. The C-terminal domain fused with a 6-His-tag named the His-tag-VpC-terminal domain was expressed successfully in soluble form in the BL21 (DE3) PlysS cell. Remarkably, both expression and purification results confirmed a high agreement in the molecular weight of the His-tag-VpC-terminal domain was 47 kDa. This work showed the His-tag-VpC-terminal domain lysed the erythrocyte membranes in the blood agar and the phosphate buffered saline (0.9%) media without adding the lecithin substrate of the phospholipase enzyme. Haemolysis occurred at all tested diluted concentrations of His-tag-VpC-terminal domain (p < 0.05), providing evidence for the independent haemolytic activity of the His-tag-VpC-terminal domain. The content of 100 ㎍ of the His-tag-VpC-terminal domain brought the highest haemolytic activity of 80% compared to that in the three remaining contents. Significantly, the His-tag-VpC-terminal domain demonstrated not to involve the phospholipase activity in Luria-Bertani agar supplemented with 1% (vol/vol) egg yolk emulsion. All results proved the vital responsibility of the His-tag-VpC-terminal domain in causing the haemolytic activity without the required activation by the phospholipase enzyme. Raw extracts of Phellinus igniarus and Phellinus pipi at 10^-1 mg/mL inhibited the haemolytic activity of the His-tag-VpC-terminal domain from 67.7% to 87.42%, respectively. Hence applying the His-tag-VpC-terminal domain as a simple biological material to evaluate quickly potential derivatives against the Vptlh in vivo conditions will accessible and more advantageous than using the whole of the Vptlh.

• Progress in Medical Physics
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• v.13 no.1
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• pp.44-50
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• 2002

CsI(T1) single crystal was grown in a Bridgman growing apparatus, which has the diameter of 11 mm and the mole ratio of 0.001 mol%. Radiation sensors were made with CsITl)crystal and two photodiodes, and measured spectroscopic characteristics and linearity for gamma-ray and X-ray. The energy resolution of CsI(T1) radiation sensor has been measured with $^{22}$ Na, $^{137}$ Cs and $^{60}$ Co gamma standard sources. Also output linearity of CsITl) sensor was measured for diagnostic radiation region. The energy resolutions of CsI(T1) radiation sensor for 0.511MeV gamma-ray from Na-22 source, 0.662MeV from Cs-137 source, and 1.17MeV and 1.332MeV from Co-60 source were 13.2%, 8.3%, 6.7%, and 5.1% respectively. Also the output linearity up to 80mAs current for 60kVp, 80kvp, 100kVp, 120kVp tube voltages has been studied.

• Journal of radiological science and technology
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• v.43 no.2
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• pp.79-85
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• 2020

The influence of metal artifact in CT image depends on the type of metal materialsm, the reconstruction algorithm, and scan parameters. The presence of metal artifacts was quantitatively evaluated by applying the standard and MAR algorithms through the phantom study. In the change of tube voltage applied the standard algorithm, metal artifact decreased to 44.9% for 80 vs 120 kVp, 24% for 100 vs 120 kVp, while the image taken at 140 kVp increased the artifact by 19% compared to 120 kVp. When the tube current was increased from 100 to 300 mA, there was no significant difference in the CT value and noise. Black band and white strike artifacts occurred up to 65.9% in the adjacent ROI of the metal driver, whereas titanium screw produced lesser metal artifact than that of the metal driver. The combination of 120kVp or higher tube voltage-standard algorithm was effective in removing black band artifacts as well as white streak by high density materials. However, MAR reconstruction algorithm was useful in improving image quality under the environment of low kVp and high density materials, without increase of radiation exposure.

• Journal of radiological science and technology
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• v.21 no.1
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• pp.29-34
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• 1998

The purpose of simple abdomen erect projection is to see the fluid level which indicates gastrointestinal ileus or free air due to perforation. we do not have to insist on low kVp technique in simple abdomen erect position as long as we can detect the fluid level and free air shadow. Therefore, the author tried to decrease patient dose by high kVp technique and to improve the image quality due to motion artifact by reduction of exposure time. [Methods] Experiment 1. * screen/film SRO1000/HRH * exposure factor : $140\;kvp{\pm}5\;kv$ with added filters, 200 mA, 0.01 sec * phantom : Acryles : 15.0 cm(equivalent to 17 cm body thickness) 17.5 cm(equivalent to 21 cm body thickness) 20.0 cm (equivalent to 25 cm body thickness) With the exposure factor for same film density($D=0.8{\pm}0.1$) and with the materials above, we tried to find out entrance skin dose and gonad dose for both male and female. Experiment 2. Burger's phantom radiography were checked to see whether there was any change of image quality according to the kVp and the added filters. Experiment 3. Using rotating meter(self made), we examined the motion artifact and the exposure time limitation. [Results and conculution] 1. Using high voltage technique of 140 kVp with added filter, Skin dose, testicle dose and ovary dose decrease to 89.3%, 47% and 71.4% respectively compare to 70 kVp technique, 2. No great changes of Burger's phantom image has detected as from 70 kVp to 140 kVp and the air hole size of Burger's phantom over 0.028 cc(Diameter 3 mm, hight 4 mm) can be distinghished. 3. 0.01 sec(1 pulse) exposure time is possible in the single phase full wave rectification that why we can quitely reduce the unsharness caused by patient's movement.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.8
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• pp.1157-1163
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• 2014

This study was conducted to observe the effects of gas composition in modified atmosphere packaging (MAP) on the shelf-life of Longissimus dorsi of Korean Native Black Pigs-Duroc Crossbred ($KNP{\times}D$) during refrigerated storage. Muscle sample was obtained from the left side of carcass of seven months old of $KNP{\times}D$ barrow. The sample was sliced into 1 cm in thickness, placed on trays (two slices/tray) and filled with different gas composition, i.e. 0:20:80/$O_2:CO_2:N_2$ (MAP1), 30:20:50/$O_2:CO_2:N_2$ (MAP2) and 70:20:10/$O_2:CO_2:N_2$ (MAP3). Other slices of sample were vacuum packed (VP) as a control. All packs were stored at $5{\pm}1^{\circ}C$. At 12 d of storage, pH value of MAP2 and MAP3 were higher (p<0.05) than that of MAP1 and pH value of MAP1 was higher (p<0.05) than that of VP. At 6 d of storage, redness ($a^*$) value of MAP2 and MAP3 were higher (p<0.05) than that of VP and MAP1 and, at 9 and 12 d of storage, redness value of MAP3 was higher (p<0.05) than that of VP, MAP1, and MAP2. At 3, 6, 9, and 12 d of storage, the 2- thiobarbituric acid reactive substances (TBARS) value of MAP3 was higher than that of MAP2 and TBARS value of MAP2 was higher than that of VP and MAP1. At 3, 6, 9, and 12 d of storage, volatile basic nitrogen values of MAP2 and MAP3 were higher (p<0.05) than those of VP and MAP1. At 3 d of storage, total aerobic plate counts of MAP2 and MAP3 were higher (p<0.05) than those of VP and MAP1 and, at 6 d of storage, total aerobic plate counts of MAP3 was higher (p<0.05) than that of MAP1 and MAP2. However, there was no significant different total aerobic plate count among MAP1, MAP2, and MAP3 at 9 and 12 d of storage. There was no significant different total anaerobic plate count among MAP1, MAP2, and MAP3 during storage. It is concluded that the MAP containing 30:20:50/$O_2:CO_2:N_2$ gas composition (MAP2) might be ideal for better meat quality for $KNP{\times}D$ meat.