• Pediatric Infection and Vaccine
• /
• v.4 no.2
• /
• pp.240-256
• /
• 1997

Purpose: To evaluate the hepatitis B vaccination program which has been conducted since 1980, Korea. Methods: This study was carry out self reported questionnaire and serologic test covering 2,072 elementary school students who were born between 1980 and 1987, selected by cluster sampling. The HBV serologic markers (HBsAg, Anti-HBs and Anti-HBc) were tested by radioimmunoassay (RIA). The contents of questionnaire include demographic data of students and parents, vaccination status, vaccination frequency, vaccination age, past history of mother's HBV test. Results: 1) The HBsAg positive rates by sex showed 3.7% for male and 2.7% for female, representing an average rate of 3.4%. The HBsAg positive rates by age group showed 5.6% for 13 years and l.5% for 6 years, representing a tendency of lowering rate as ages being younger. 2) The pre-natal HBV test rate was 10.2%, while post-natal HBV test rate was 42.5%. The test showed that the parents' educational level being higher than others, the pre- and post-natal HBV test showed higher rates. In case the fathers occupation being office worker, the post-natal HBV test showed a higher rate compared with other occupation. 3) Overall vaccination rate was 82.6%, complete vaccination rate 69.8%, booster injection rate 42.8%. The vaccination rate, complete vaccination rate and booster injection rate increased as the age being younger. If the educational level of parents were higher, the vaccination rate, complete vaccination rate and booster injection rate showed higher rates. Younger students showed younger vaccination age, and higher educational background of family showed younger vaccination ages. 4. With regard to positive rate of HBV markers by vaccination age, HBsAg and Anti-HBc positive rate showed higher degrees in the following order; preschool age (1-6 years), school age (6-13 years) and infancy (0-1 year). Anti-HBs positive rate was increased as the frequency of vaccination increased. Five years after initial complete vaccination, minimum protective rate was lowest, 69.6%.

• Applied Biological Chemistry
• /
• v.51 no.3
• /
• pp.212-218
• /
• 2008

This study was performed to determine the antimutagenic and anticancer effects of ethanol extract of buckwheat sprout using Ames test and SRB assay, respectively. An ethyl acetate fraction (200 ${\mu}/plate$) from the ethanol extract of buckwheat sprout showed inhibition rate of 80.6% against the mutagenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in Salmonella typhimurium TA100 strain. Also the ethyl acetate fraction (200 ${\mu}/plate$) showed higher antimutagenic activity than other fractions against the mutagenesis induced by 4-nitroquinoline-1-oxide (4NQO) in Salmonella typhimurium TA98 and TA100. In addition, the ethyl acetate fraction (200 ${\mu}/plate$) showed high antimutagenic effect of 80.9% and 85.9% against the mutation of TA98 and TA100 strains induced by 3-amino-1,4-dimethyl-5H-pyrido-(4,3-b)indol (Trp-P-1), respectively. The cytotoxic effects of each solvent fraction from the ethanol extract of buckwheat sprout against human cancer cell lines including lung carcinoma (A549), gastric carcinoma (AGS), breast adenocarcinoma (MCF-7), hepatocellular carcinoma (Hep3B), and colon adenocarcinoma (Colo 205) were investigated. The ethyl acetate fraction of buckwheat sprout ethanol extract at the concentration of 1.0 mg/ml showed strong cytotoxic activities of 70.3, 94.8, 79.6, 82.3, and 73.2% against A549, AGS, MCF-7, Hep3B and Colo 205 cancer cell lines, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.7
• /
• pp.334-341
• /
• 2016

In this paper, the study of a waveguide aperture-coupled feed-structured antenna has been conducted for the purpose of applying it to a wireless back-haul system sufficient for high-capacity gigabits-per-second data rates. For this study, a $32{\times}32$ waveguide slot sub-array antenna with a corporate-feed structure was designed and produced. Also, this antenna is used at 57 GHz to 66 GHz in the V-band. The construction of the antenna is a laminated form with radiating parts (outer groove and slot, cavity), a coupled aperture, and feeds in each. The antenna was designed with HFSS, which is based on 3D-FEM, produced with aluminum processed by a precision-controlled milling machine, and assembled after a silver-plating process. The measurement result from analysis of the characteristics of the antenna shows that return loss is less than -12 dB, VSWR < 2.0, and a wide bandwidth ranges up to 16%. An overall first side lobe level is less than -12.3 dB, and a 3 dB beam width is narrow at about $1.85^{\circ}$. Also, antenna gain is 38.5 dBi, offering high efficiency exceeding 90%.

• Korean Journal of Agricultural Science
• /
• v.24 no.2
• /
• pp.275-282
• /
• 1997

The prcx.iuction of extracellular 1,4-${\beta}$-glucanase by Cellulomonas sp. CS1-1 on microcrystalline cellulose, sigmacell was maximal after 5-day cultivation as 280 units/mL, which was three times higher than the level produced on carboxymethyl cellulose. A carboxymethyl cellulase containing the carbohydrate of 8.2% was purified from the culture filtrate by successive procedures of column chromatographies. Purification factor was calculated as 22-folds with the specific carboxymethyl cellulase activity of 31.9 units/mg. The molecular weight and isoelectric point of the purified enzyme were 54,000 and pI 5.4, respectively. The optimal pH and temperature were 6.0 and $45^{\circ}C$, and the enzyme was stable between pH 6.5 and 7.5 and below $50^{\circ}C$. The estimated Km and Vmax were 10 mg/mL and $6.25{\mu}mol/min$ for carboxymethyl cellulose and 30.3 mg/mL and $2.85{\mu}mol/min$ for sigmacell, respectively. The enzyme was partially inhibited by $Ag^+$, $Zn^{+{+}}$, $Fe^{+{+}}$ and EDTA, while completely inhibited by $Cd^{+{+}}$ and $Hg^{+{+}}$ at 1 mM concentration.

• Journal of Preventive Medicine and Public Health
• /
• v.24 no.4 s.36
• /
• pp.465-472
• /
• 1991

This study was designed to estimate the prevalence of hepatitis C virus(HCV) infection in drug abusers. The subjects were 141 inpatients who had been admitted to a general hospital with the symptoms and signs of methamphetamine intoxication. Seroprevalence of antibody to the hepatitis C virus(anti-HCV) was 60.3%(85/141) and it was higher in the group with increased frequency and duration of drug abuse, but such a relationship was not found in the seroprevalence of hepatitis B surface antigen(HBsAg). These findings suggested the possibility of high prevalence of HCV infection in methamphetamine abusers, and the importance of repetitive percutaneous injection in the transmission of HCV infection.

• Bulletin of the Korean Chemical Society
• /
• v.35 no.5
• /
• pp.1356-1364
• /
• 2014

A new conjugated copolymer, poly{4,8-bis(triisopropylsilylethynyl)benzo[1,2-b:4,5-b']dithiophene-alt-4,7- bis(5-thiophen-2-yl)-5,6-difluoro-2-(heptadecan-9-yl)-2H-benzo[d][1,2,3]triazole} (PTIPSBDT-DFDTBTz), is synthesized by Stille coupling polycondensation. The synthesized polymer has a band gap energy of 1.9 eV, and it absorbs light in the range 300-610 nm. The hole mobility of a solution-processed organic thin-film transistor fabricated using PTIPSBDT-DFDTBTz is $3.8{\times}10^{-3}cm^2V^{-1}s^{-1}$. Bulk heterojunction photovoltaic cells are fabricated, with a conventional device structure of ITO/PEDOT:PSS/polymer:$PC_{71}BM$/Ca/Al ($PC_{71}BM$ = [6,6]-phenyl-$C_{71}$-butyric acid methyl ester); the device shows a power conversion efficiency (PCE) of 2.86% with an open-circuit voltage ($V_{oc}$) of 0.85 V, a short-circuit current density ($J_{sc}$) of 7.60 mA $cm^{-2}$, and a fill factor (FF) of 0.44. Inverted photovoltaic cells with the structure ITO/ethoxylated polyethlyenimine/ polymer:$PC_{71}BM/MoO_3$/Ag are also fabricated; the device exhibits a maximum PCE of 2.92%, with a $V_{oc}$ of 0.89 V, a $J_{sc}$ of 6.81 mA $cm^{-2}$, and an FF of 0.48.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.2 no.2
• /
• pp.169-177
• /
• 1999

Purpose: To evaluate the efficacy of interferon alpha therapy with or without prednisolone in children with chronic hepatitis B. Methods: Twenty-eight children (22 boys, 6 girls, mean age 130 months) had seropositive results for HBsAg, HBeAg and HBV DNA; 11 had chronic persistent hepatitis and 17 had chronic active hepatitis. The patients were divided into two groups depending upon their inflammatory activity on liver biopsy, pretreatment serum ALT levels and HBV DNA levels. Fourteen children (group 1: chronic active hepatitis, ALT ${\geq}$ 100 IU/L and HBV DNA ${\leq}$ 100 pg/$300\;{\mu}L$) received interferon alpha 2a 5 $MU/m^2$ of body surface three times weekly for 6 months. Fourteen children (group 2: chronic persistent hepatitis or chronic active hepatitis with ALT < 100 IU/L or HBV DNA > 100 pg/$300\;{\mu}L$) received prednisolone in decreasing daily doses of 60 mg/$m^2$, 40 mg/$m^2$, and 20 mg/$m^2$, each for 2 weeks, followed after 2 weeks by interferon alpha 2a on the same schedule. At the end of therapy, 3 end points were analyzed: HBeAg seroconversion, serum ALT normalization rate and clearance of serum HBV DNA. Results: At the end of treatment, HBe antigen-to antibody seroconversion was higher but not more significant in group 1 than group 2 (71.4% vs. 50.0%). Only one patient in group 2 who lost HBeAg, also cleared HBsAg. ALT normalization was similar in both groups (64.3% in group 1 vs. 55.6% in group 2). Clearance of serum HBV DNA was observed in 78.6% of patients in group 1 and 64.3% in group 2, but no significant differences. Complete response was similarly achieved in both groups (57.1% in group 1 vs. 50.0% in group 2). Interferon alpha therapy with prednisolone priming was well tolerated and all children finished therapy. Conclusion: The combined therapy with prednisolone followed by interferon alpha may be safe and effective in inducing a serological and biochemical remission of the disease in approximately 50% of children with chronic hepatitis B and with a high level of viral replication and less active disease. However, a controlled study should be performed to confirm these results.

• The Journal of Korean Academy of Prosthodontics
• /
• v.49 no.4
• /
• pp.316-323
• /
• 2011

Purpose: The purpose of this study was to investigate the effect of different thread designs on the marginal bone stresses around dental implant. Materials and methods: Standard ITI implant(ITI Dental Implant System; Straumann AG, Waldenburg, Switzerland), 4.1 mm in diameter and 10 mm in length, was selected as control. Test implants of four different thread patterns were created based on control implant, i.e. maintaining all geometrical design of control implant except thread pattern. Four thread designs used in test implants include (1) small V-shape screw (model A), (2) large V-shape screw (model B), (3) buttress screw (model C), and (4) trapezoid screw (model D). Surface area for unit length of implant was 14.4 $mm^2$ (control), 21.7 (small V-shape screw), 20.6 (large V-shape screw), 17.0 (buttress screw) and 28.7 $mm^2$ (trapezoid screw). Finite element models of implant/bone complex were created using an axisymmetric scheme with the use of NISA II/DISPLAY III (Engineering Mechanics Research Corporation, Troy, MI, USA). A load of 100 N applied to the central node on the crown top either in parallel direction or at 30 degree to the implant axis (in order to apply non-axial load to the implant NKTP type 34 element was employed). Quantification and comparison of the peak stress in the marginal bone of each implant model was made using a series of regression analyses based on the stress data calculated at the 5 reference points which were set at 0.2, 0.4, 0.6, 0.8 and 1.0 mm from implant wall on the marginal bone surface. Results: Results showed that although severe stress concentration on the marginal bone cannot be avoided a substantial reduction in the peak stress is achievable using different thread design. The peak marginal bone stresses under vertical loading condition were 7.84, 6.45, 5.96, 6.85, 5.39 MPa for control and model A, B, C and D, respectively. And 29.18, 26.45, 25.12, 27.37, 23.58 MPa when subject to inclined loading. Conclusion: It was concluded that the thread design is an important influential factor to the marginal bone stresses.

• Journal of Plant Biotechnology
• /
• v.34 no.2
• /
• pp.139-144
• /
• 2007

Hypocotyl explants of Chinese cabbage (cvs. "Jeong Sang") produced transgenic calli on callus induction medium (MS salt, B5 vitamin, 5 mg/L acetosyringone, 1 mg/L 2,4-D, 3% sucrose, 400 mg/L cefotaxime, 100 mg/L paromomycin, pH 5.8) after cocultivation with strains of Agrobacterium tumefaciens (EHA101, LBA4404, GV3101) harboring the pPTN290 containing paromomycin-resistance gene as a selectable marker, and then they transferred to root induction medium (1/2MS salt, MS vitamins, 2% sucrose, 100 mg/L paromomycin, 100 mg/L cefotaxime, pH 5.8) and shoot induction medium (MS salt, B5 vitamin, 4 mg/L $AgNO_3$, 4 mg/L 6-benzyladenine, 3 mg/L alpha-naphthaleneacetic acid, 100 mg/L paromomycin, 100 mg/L cefotaxime, 3% sucrose, pH 5.8) in order. There was a significant difference in the frequency of transgenic calli depending on Agrobacterium strains. In particular, the highest frequency (6.1%) of transgenic calli was obtained from the hypocotyls cocultivated with EHA101 strains. Also, the frequency (%) of transgenic root and plants from each transgenic callus clone were obtained with 60.7% and 38.2% in EHA101, with 8.3% and 0% in LBA4404, with 20.5% and 85.7% in GV3101 strains, respectively. They were grown to maturity in a greenhouse and normally produced $T_2$ seeds. GUS histochemical assay for progeny ($T_2$) revealed that the transgenes was expressed in the plant genome, and progeny analysis from 7 independent transgenic events demonstrated that the transformants transmitted the transgene as a single or multiple functional locus.

• Korean Journal of Medicinal Crop Science
• /
• v.12 no.1
• /
• pp.36-42
• /
• 2004

The immune activation and anticancer activities of the water and ethanol extracts from Artemisia capillaris Thunb. were studied. The growth of human hepatocarcinoma and human gastric cancer cell was inhibited by the addition of $1.0\;mg/m{\ell}$ of the water extract, by about 77% and 95%, respectively. The growth of human breast cancer cells was also inhibited by addition of $0.5\;mg/m{\ell}$ of both water and ethanol extracts by 88%. The growth of human normal lung cell, HEL299 was inhibited by 15% indicating very low cytotoxicity of both extracts. Overall selectivity of the both extracts on several human cancer cell line was over 2.5. The growth of both human B and T cells was enhanced up to 1.6 to 2.1 times by adding the ethanol extracts. The secretion of cytokines, $TNF-{\alpha}$ and IL-6, from human B cells was also increased showing $68\;pg/m{\ell}$ and $67\;pg/m{\ell}$, respectively, compared to $35{\sim}40\;pg/m{\ell}$ of the control. In terms of the immune activity, there was not much difference between water and ethanol extracts of Artemisia capillaris Thunb. It implies that the extraction solvent could not differ the biological activities of the extracts. Based on these results, Artemisia capillaris Thunb. can be developed into a potentially useful cancer chemoprentive agent.