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Cell-mediated immunity in mice infected with Acanthumoeba culbertsoni (Acanthamoeba culbertsoni 감염에 있어서 세포 매개성 면역)

  • Kim, Myeong-Jun;Sin, Ju-Ok;Im, Gyeong-Il
    • Parasites, Hosts and Diseases
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    • v.28 no.3
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    • pp.143-154
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    • 1990
  • Observations were made on the differences of cell-mediated responses in mice of three infectiorl groups di여erently scheduled in their severity with pathogenic Acanthamoeba culbertseni. Infections were done by dropping $5{\;}{\mu}l$ saline suspension containing $3{\times}10^3,{\;}1{\times}10^4,{\;}or{\;}1{\times}10^5$ trophosoites, respectively. Amoebae were cultured anenically in CGV medium and inoculated into the right nasal cavity of CSH/HeJ mice aging around 6∼8 weeks, under the anesthesia by intraperitoneal injection of secobarbital. Delayed type hypersensitivity (DTH) responses in footpad and blastogenlc responses of mouse spleen cells using ($^3H$)-thymidine and the serum antibody titer were measured up to day 14 after infection, and natural killer cell activities were measured up to day, i after infection. The results obtained in this study were as follows: 1. The mice infected with $3{\times}10^3$ trophosoites showed mortality rate of 17%, and 345 in the mice infected with $1{\times}10^4$ trophozoites and 65% with $1{\times}10^5$ trophozoites. 2. In regard to DTH responses in all experimental groups, the level increased on day 7 and declined on day 14 after infection, but their differences could not be noted between infected and control groups. 3. The blastogenic responses of splenocytes treated with amoeba Iysates and lipopolysaccharides (LPS) showed no difference from the control group. The blastogenic responses of splenocytes treated with concanavalin A were declined significantly in the experimental group as compared with the control group, but the blastogenic responses of splenocytes treated with polyinosinic acid were not different from the control group. There was also no difference among three infected groups. 4. The cytotoxic activity of the natural killer cells was activated on day 1 after infection and declined to the level of control group on day 2 in all experimental groups. On day 5 after infection, the natural killer cell cytotoxicity was significantly suppressed as compared with the control groups. 5. The serum antibody titers of the infected mice increased after day 7, but there was no statistical difference between the three infected groups. In summary of the results, there was no difference in cell-mediated immune responses of three experimental groups scheduled with different infection intensities. But there was a significant difference in cell$.$mediated immune responses between infected and control mice. It is considered that cell-mediated immune responses should be involved in murine model infected with A. culbertsoni.

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Expression of tissue-type plasminogen activator and its derivative proteins in transgenic alfalfa plants (조직형 플라스미노겐 액티베이터와 관련 변이 단백질들을 발현하는 알팔파 형질전환체)

  • Sim, Joon-Soo;Rhee, Yong;Ko, Hyo-Rim;Pak, Hyo-Kyung;Kim, Hyeong-Mi;Lim, Kyu-Hee;An, Ki-Seong;Kim, Yong-Hwan;Hahn, Bum-Soo
    • Journal of Plant Biotechnology
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    • v.36 no.1
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    • pp.30-37
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    • 2009
  • Tissue-type plasminogen activator (t-PA) is a thrombolytic agent important in fibirn clot lysis. T-PA causes fibirn-specific plasminogen activation. Six binary vectors harboring t-PA and its derivative genes were cloned and expressed in transgenic alfalfa plants. The insertion of the t-PA and its derivative genes in genomic DNA of alfalfa plants was confirmed by PCR. The presence of the t-PA and its derivative transcripts in total RNAs of the transgenic alfalfa leaves was verified by RT-PCR. ELISA experiments demonstrated that the highest level of recombinant t-PA expression was $75.1{\mu}g$/ total soluble protein (mg) in alfalfa plants. The amount of recombinant t-PA and its derivative proteins in transgenic plants was estimated to range from 9.7 to $39.5{\mu}g$/ total soluble proteins (mg). Western blot analysis of the transformed alfalfa leaves revealed bands of approximately 68-kDa recombinant t-PA and its derivative proteins. The fibrinolysis of recombinant t-PA and its derivative proteins was confirmed by a fibrin plate assay (range from 3.2 to 8.1 cm). The results presented provide information for the development of an additional production of recombinant human proteins having pharmaceutical applications using transgenic plants.

Adjuvant Effect of PAMAM Dendrimer on the Antigenicity of Keyhole Limpet Hemocyanin in Balb/c Mice (Balb/c 마우스에서 Keyhole limpet hemocyanine (KLH)의 항원성에 대한 PAMAM dendrimer 의 면역증강 효과)

  • Lee, Ga-Young;Kim, Min Jee;Kim, So Yeon;Lee, Kyung Bok;Oh, Dong Hyun;Cho, Young Ho;Yoo, Yung Choon
    • Journal of Life Science
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    • v.30 no.10
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    • pp.905-911
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    • 2020
  • The adjuvant effect of PAMAM dendrimer G4 (PAMAM) on the induction of humoral and cellular immune responses against keyhole limpet hemocyanin (KLH) was examined. Mice were immunized subcutaneously twice at two-week intervals with KLH, with or without PAMAM dendrimer (100 ㎍/mouse), and the mice immunized with KLH+PAMAM showed significantly higher antibody titers against KLH than those immunized with KLH alone. The assay for determining the isotypes of the antibodies showed that PAMAM augmented the KLH-specific antibody titers of IgG1, IgG2a, IgG2b, IgG3, and IgM. In addition, mice immunized twice with KLH+PAMAM followed by a subcutaneous injection of KLH (20 ㎍/site) 7 weeks after the primary immunization exhibited a higher delayed-type hypersensitivity (DTH) reaction than those treated with KLH alone. In an in vitro analysis of T lymphocyte proliferation in response to KLH in week 8, the splenocytes of mice treated with KLH+PAMAM showed significantly higher proliferating activity than those treated with KLH alone, and the culture supernatants of cell cultures from mice immunized with added PAMAM dendrimer showed higher levels of KLH-specific cytokine (IL-4 and IFN-r) production. These results suggest that PAMAM dendrimer G4 possesses a potent immune-adjuvant activity for enhancing both humoral and cell-mediated immunity specific to foreign antigens.

Protection of UV-derived Skin Cell Damage and Anti-irritation Effect of Juniperus chinensis Xylem Extract (향나무추출물의 광손상으로부터 피부세포 보호와 자극완화 효과에 대한 연구)

  • 김진화;박성민;심관섭;이범천;표형배
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.30 no.1
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    • pp.63-71
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    • 2004
  • The human skin is constantly exposed to environmental irritants such as ultraviolet, smoke, chemicals. Free radicals and reactive oxygen species (ROS) caused by these environmental facts play critical roles in cellular damage. These irritants are in themselves damaging to the skin structure but they also participate the immensely complex inflammatory reaction. The purpose of this study was to investigate the skin cell protective effect of Juniperus chinensis xylem extract on the UV and SLS-induced skin cell damages. We tested free radical and superoxide scavenging effect in vitro. We found that Juniperus chinensis xylem extracts had potent radical scavenging effect by 98% at 100 $\mu\textrm{g}$/mL. Fluorometric assays of the proteolytic activities of matrix metalloproteinase-l(MMP-1, collagenase) were performed using fluorescent collagen substrates. UV A induced MMP-1 synthesis and activity were analyzed by enzyme-linked immunosorbent assay (ELISA) and gelatin-based zymography in skin fibroblasts. The extract of Juniperus chinensis showed strong inhibitory effect on MMP-1 activities by 97% at 100 $\mu\textrm{g}$/mL and suppressed the UVA induced expression of MMP-1 by 79% at 25 $\mu\textrm{g}$/mL. This extract also showed strong inhibition on MMP-2 activity in UVA irradiated fibroblast by zymography. We also examined anti-inflammatory effects by the determination test of proinflammatory cytokine, interleukin 6 in HaCaT keratinocytes. In this test Juniperus chinensis decreased expression of interleukin 6 about 30%. Expression of prostaglandin E$_2$, (PGE$_2$) after UVB irradiation was measured by competitive enzyme immunoassay (EIA) using PGE$_2$ monoclonal antibody. At the concentrations of 5-50 $\mu\textrm{g}$/mL of the extracts, the production of PGE$_2$ by HaCaT keratinocytes (24 hours after 10 mJ/$\textrm{cm}^2$ UVB irradiation) was significantly inhibited in culture supernatants (p〈0.05). The viability of cultured HaCaT keratinocytes was significantly reduced at the doses of above 10 mJ/$\textrm{cm}^2$ of UVB irradiation, but the presence of these extracts improved cell viability comparing to control after UVB irradiation. We also investigated the protective effect of this extract in sodium lauryl sulfate (SLS)-induced irritant skin reactions from 24 hour exposure. Twice a day application of the extract for reducing local inflammation in human skin was done. Irritant reactions were assessed by various aspects of skin condition, that is, erythema (skin color reflectance) and transepidermal water loss (TEWL). After 5 days the extract was found to reduce SLS-induced skin erythema and improve barrier regeneration when compared to untreated symmetrical test site. In conclusion, our results suggest that Juniperus chinensis can be effectively used for the prevention of UV and SLS-induced adverse skin reactions such as radical production, inflammation and skin cell damage.

Inhibitory Effect of Ophioglossum vulgatum on Free Radical and MMP Expression in UV-irradiated Human Dermal Fibroblasts (병이소초 추출물의 항산화 및 MMP 발현 저해 효과)

  • Kim, Jin-Hwa;Oh, Jung-Young;Lee, Geun-Soo;Zhang, Yong-He;Pyo, Hyeong-Bae
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.35 no.4
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    • pp.287-292
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    • 2009
  • Human skin is constantly exposed to environmental irritants such as smoke, chemicals and ultraviolet (UV). Free radicals and reactive oxygen species (ROS) caused by these environmental irritants play critical roles in cellular damage. In this study, to investigate the skin cell protective effect of Ophioglossum vulgatum extract, we investigated its effects on intercellular antioxidative activity and UVA-induced MMP expression in human dermal fibroblasts (HDFs). The dried O. vulgatum was extracted in a mixture of ethanol and water (1 : 1) for 24 h at room temperature. The extract was filtered and concentrated in vacuo and lyophilized. For testing intracellular ROS scavenging activity the cultured HDFs were analyzed by increase in DCF fluorescence upon exposure to UVB $20\;mJ/cm^2$. After treatment of O. vulgatum extracts, intracellular ROS levels were measured by luminescence spectrophotometer. Enzyme linked immuno sorbent assay (ELISA), and RT-PCR techniques were used for evaluating the effects of O. vulgatumon on MMP protein and mRNA expression in UVA irradiated HDFs. O. vulgatum extract was found to have ROS scavenging activity with the $IC_{50}$ values of $18.2\;{\mu}g/mL$ against superoxide radicals in the xanthine/xanthine oxidase system. After treatment of O. vulgatum extracts, the oxidation of CM-DCFDA was inhibited effectively and O. vulgatum extracts showed a potent free radical scavenging activity by 30.4 % at $100\;{\mu}g/mL$ in UVB-irradiated HDFs. UVA induced MMP protein expression was reduced 37.7 % by treatment with O. vulgatum extract, and MMP-1 mRNA expression was reduced in a dose-dependent manner. Taken together, these results suggest that O. vulgatum extract prevents the skin cell damage induced by UV irradiation, and implies that O. vulgatum extract may be useful as a new ingredient for anti-aging cosmetics.

The current status and control measures of BSE in the worldwide (국내, 외 광우병의 발생 현황과 대응 방안)

  • Yoo, Han-Sang
    • 한국환경농학회:학술대회논문집
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    • 2009.07a
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    • pp.273-282
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    • 2009
  • The transmissible spongiform encephalopathies (TSEs) disease group are fatal neurodegenerative disorders affecting a wide range of hosts. The group includes kuru and Creutzfeldt-Jakob disease (CJD) in humans, scrapie in sheep and goats and Bovine spongiform encephalopathy (BSE) in cattle. The exact nature of the infectious agent involved in the transmission of these diseases remains controversial. However, a central event in their pathogenesis is the accumulation in infected tissues of an abnormal form of a host-encoded protein, the prion protein (PrP). Whereas the normal cellular protein is fully sensitive to protease ($PrP^{sen}$), the disease-associated prion protein ($PrP^d$) is only partly degraded ($PrP^{res}$), its amino-terminal end being removed. BSE was first reported in the mid-80s in the UK. Ten years later, a new form of human prion disease, variant CJD (vCJD) developed in the wake of the BSE epidemic, and there is now strong scientific evidence that vCJD was initiated by the exposure of humans to BSE-infected tissues, thus indicating a zoonotic disease. However, the ban on the feeding of animal-derived proteins to ruminants, and the apparent lack of vertical transmission of BSE, have led to a decline in the incidence of the disease within cattle herd and therefore, an assumed decreased risk for human contacting vCJD. The origin of the original case(s) of BSE still remains an enigma even though three hypotheses have been raised. Hypotheses are i) sheep- or goat-derived scrapie-infected tissues included in meat and bone meal fed to cattle, ii) a previously undetected sporadic or genetic bovine TSE contaminating cattle feed or iii) originating from a human TSE through animal feed contaminated with human remains. A host cellular membrane protein ($PrP^C$), which is abundant in central nervous system tissue, appear to be conformationally altered in the diseased host into a prion protein ($PrP^{Sc}$). This $PrP^{Sc}$ is detergent insoluble and partially protease-resistant ($PrP^{res}$). The term $PrP^{res}$ is normally used to describe the protein detected after protease treatment, in techniques such as Western immunoblotting, and enzyme-linked immunosorbant assay using fresh/frozen tissue. Immunohistochemistry may performed with formalin-fixed tissues. Also, clinical signs of the BSE are one of the major diagnostic indicators. Recently, atypical forms (known as H- and L-type) of BSE have appeared in several European countries, Japan, Canada and the United States. An unusual case was also reported in a miniature zebu. The atypical BSE fall into two groups based on the relative molecular mass (Mm) of the unglycosylated $PrP^{res}$ band relative to that of classical BSE, one of the higher Mm (H-type) and the other lower (L-type). Both types have been detected worldwide as rare cases in older animals, at a low prevalence consistent with the possibility of sporadic forms of prion diseases in cattle. This raises the unwelcome possibility that vCJD could increase in the human population. Now, active surveillance program against BSE is going on in Korea. In regional veterinary service lab, ELISA is applied to screen the BSE in slaughter and confirmatory tests by Western immunoblotting and immunohistochemisty are carried out if there are positive or suspect in the screening test. Also, the ruminant feed ban is rigorously enforced. Removal of specified risk materials such as brain and spinal cord from cattle is mandatory process at slaughter to prevent the infected material from entering the human food chain.

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Establishment and Characterization of Bone Marrow Mesenchymal Stromal/Stem Cells (MSCs) Derived from ${\alpha}$-1,3-Galactosyltransferase Knock Out(GalT KO) Pig (${\alpha}$-1,3-Galactosyltransferase Knock Out(GalT KO) 돼지유래 골수 중간엽 줄기세포의 특성 규명)

  • Ock, Sun-A;Oh, Keon Bong;Hwang, Seongsoo;Im, Seoki;Kim, Youngim;Park, Jin-Ki
    • Journal of Embryo Transfer
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    • v.28 no.3
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    • pp.281-287
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    • 2013
  • A major barrier to progress in pig to primate organ transplantation or cell therapy is the presence of terminal ${\alpha}$-1,3-galactosyl epitopes on the surface of pig cells. Therefore, the purpose of this experiment was to establish and cha- racterize mesenchymal stromal/stem cells (MSCs) derived from ${\alpha}$-1,3-galactosyltransferase (GalT) knock out (GalT KO) pig to confirm their potential for cell therapy. Bone marrow (BM)-MSCs from GalT KO pig of 1 month old were isolated by Ficoll-Paque PLUS gradient and cultured with A-DMEM + 10% FBS on plastic dishes in 5% $CO_2$ incubator at 38.5. GalT KO BM-MSCs were analyzed for the expression of CD markers ($CD45^-$, $29^+$, $90^+$ and $105^+$) and in vitro differentiation ability (adiopogenesis and osteogenesis). Further, cell proliferation capacity and cell aging of GalT KO BM-MSCs were compared to Wild BM-MSCs by BrdU incorporation assay (Roche, Germany) using ELISA at intervals of two days for 7 days. Finally, the cell size was also evaluated in GalT KO and Wild BM-MSCs. Statistical analysis was performed by T-test (P<0.05). GalT KO BM-MSCs showed fibroblast-like cell morphology on plastic culture dish at passage 1 and exhibited $CD45^-$, $29^+$, $90^+$ and $105^+$ expression profile. Follow in ginduction in StemPro adipogenesis and osteogenesis media for 3 weeks, GalT KO BM-MSCs were differentiated into adipocytes, as demonstrated by Oilred Ostaining of lipid vacuoles and osteocytes, as confirmed by Alizarinred Sstaining of mineral dispositions, respectively. BrdU incorporation assay showed a significant decrease in cell proliferation capacity of GalT KO BM-MSCs compared to Wild BM-MSCs from 3 day, when they were seeded at $1{\times}10^3$ cells/well in 96-well plate. Passage 3 GalT KO and Wild BM-MSCs at 80% confluence in culture dish were allowed to form single cells to calculate cell size. The results showed that GalT KO BM-MSCs($15.0{\pm}0.4{\mu}m$) had a little larger cell size than Wild BM-MSCs ($13.5{\pm}0.3{\mu}m$). From the above findings, it is summarized that GalT KO BM-MSCs possessed similar biological properties with Wild BM-MSCs, but exhibited a weak cell proliferation ability and resistance to cell aging. Therefore, GalT KO BM-MSCs might form a good source for cell therapy after due consideration to low proliferation potency in vitro.

Purification of cystic fluid antigen of Taenia solium metacestodes by affinity chromatography using monoclonal antibody and its antigenic characterization (단세포군항체에 의한 유구낭미충 낭액 특이항원의 순수분리 및 항원특성 관찰)

  • Kim, Suk-Il;Kang, Shin-Yong;Cho, Seung-Yull;Hwang, Eung-Soo;Cha, Chang-Yong
    • Parasites, Hosts and Diseases
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    • v.24 no.2
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    • pp.145-158
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    • 1986
  • This study was undertaken to purify cystic fluid (CF) antigen of Taenia solium metacestodes by affinity chromatogaphy using specific monoclonal antibody(McAb) and to characterize the antigenicity of the purified antigen. The hybridoma cell lines, prepared by fusion between mouse plasmacytoma and spleen cells from BALB/c mice immunized with CF, secreted antibodies reacting to various helminthic antigens. Majority of cell lines reacted to CF only but some also reacted to parenchymal antigen of T. solium metacestodes, adult T. saginata, sparganum, hydatid cystic fluid, Paragonimus westermani and Clonorchis sinensis, either in combination with CF, other antigens or independently. Cloned cells derived from monoclonal lines also produced antibodies reacting either to CF only or to other helminthes in combination or independently. These results indicated that CF of T. solium metacestodes contained proteins which possessed antigenic determinants not only specific to CF but also cross reactive with the afore-mentioned helminthes. CF of T. solium metacestodes was purified by affinity chromatography using the McAb which reacted to CF and parenchymal antigens. The affinity-purified antigen (A-Ag) and unbound pool CF (U-Ag) were separated. A-Ag showed 2 protein bands by disc-PAGE whereas CF exhibited 6 bands and U-Ag consisted of all bands CF had. The diagnostic significance of A-Ag was evaluated by ELISA in human neurocysticercosis and other helminthic and neurologic diseases. By A-Ag, the levels of the specific IgG antibody, as shown by absorbance in sera and CSF, were lower than those of CF and U-Ag. Accordingly, the sensitivity was about 70% of CF and U-Ag. However, the nonspecific positive reactions to CF and U-Ag, observed in sparganosis, T. saginata infection and paragonimiasis did not occur when A-Ag was used. These results indicated that the affinity-purified A-Ag had the higher specificity but the lower sensitivity as a diagnostic antigen in cysticercosis, probably because it only detected a single or limited numbers of monospecific antibodies among the diverse polyclonal antibodies produced in the patients with neurocysticercosis.

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Relation between Helicobacter pylori Infection and Socioeconomic Status in Korean Adolescents (Helicobacter pylori 감염과 사회경제적 요인에 대한 연구)

  • Jung, Min-Kyong;Kwon, Young-Se;Choe, Hyon;Choe, Yon-Ho;Hong, Yun-Chul
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.3 no.1
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    • pp.17-22
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    • 2000
  • Purpose: This study was conducted to evaluate the association between H. pylori infection and socioeconomic status and to determine the current prevalence of H. pylori infection in Korean adolescents. Methods: A structured questionnaire was sent to the children's parents to obtain demographic information on the parents and environmental information. Of the 532 questionnaires sent out, 375 (70.5%; 170 girls and 205 boys) were returned. Their ages ranged from 10 to 15 years (mean, 12.9 years). After collecting blood samples, we measured serum IgG antibody to H. pylori using ELISA method. The association of risk factors such as age, sex, socioeconomic class, type of house, and crowding index with H. pylori infection were analyzed by multiple regression analysis. Socioeconomic status was estimated from the parents' education and occupation using a modified Hollingshead index. Results: The prevalence rate of H. pylori infection was 16.8% (63/375). It increased with age (10.3% at 10~11 years, 15.9% at 12~13 years, and 20.7% at 14~15 years). The H. pylori infection was inversely related to the socioeconomic class (6.3% for the upper class, 16.0% for the middle class, and 20.0% for the lower calss). Crowding condition and type of house did not affect significantly on seroprevalence of H. pylori infection. After logistic regression, we found that the odds ratio for age was 2.2 (95% confidence interval 0.9~5.4), and for socioeconomic status, 3.6 (95% confidence interval 0.5~28.9). Conclusion: The prevalence of H. pylori infection in Korean adolescents was 16.8%. It related inversely to socioeconomic status but was not statistically significant. Socioeconomic status based on parents' education and occupation seemed to affect more on H. pylori seroprevalence than crowding or type of house did.

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Analysis of Immunogenicity after Hepatitis B Vaccination in Korea by Literature Review (문헌 분석에 의한 B형 간염 백신의 항체 양전률의 비교)

  • Roh, Hye Ok;Lee, Woo Gill;Sohn, Young Mo
    • Pediatric Infection and Vaccine
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    • v.5 no.2
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    • pp.245-257
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    • 1998
  • Purpose : Although hepatitis B vaccine has been available to general population in Korea since 1983, it was difficult to compare various types of hepatitis B virus(HBV) vaccines primarily due to the differences in vaccination schedule, dosage, test methods and seropositive antibody level. In this study we reviewed the results of previous studies published in Korea, which include antibody positive rates and antibody titers of various vaccines, and examined the immunogenicity of these HBV vaccines. Methods : Studies published in medical journals, university journals concerning antibody positive rates following hepatitis B vaccination were reviewed. Inclusion criteria were those studies in which seroprotective antibody rate of 10mIU/mL or the sample ratio unit of 10 RU were used as the cut-off value and in which the test methods were RIA or ELISA. Exclusion criteria were; 1) unclear or inconsistent vaccine dosage, 2) no record of antibody titers or seroconversion rate, 3) no defined antibody rate or ratio for positive rating and 4) the vaccination schedule other than 0-1-2 months or 0-1-6 months. Results : 23 out of 52 studies were subjected for the review for seroconversion rates. 1) As for the immunogenicity in each age group, the seroconversion rates of Hepaccine(Cheil Jedang) were 85.1% in infants, 83.3% in children and 62.7% in adults, indicating higher rates in infants and children compared to adults(P<0.01). The seroconversion rates of Hepavax(Korea Green Cross) were 84.7%, 81.1% and 90.8%, indicating higher rates in infants and adults compared to children(P<0.01). 2) The seroconversion rate of Hepavax was 85.6% with 0-1-6 mo. schedule, 78.5% with 0-1-2 mo. schedule with a statistically significant difference(P<0.01). 4) There was no difference of seroconversion rates between the two doses of Hepavax, $5{\mu}g$ and $10{\mu}g$ in infants and children. 5) In adults the seroconversion rates were 62.7% with Hepaccine, 90.8% with Hepavax, and 94.8% with Engerix-B(SmithKline Beecham). Conclusion : In Korea, the incidence of chronic hepatitis B is high and changing the schedule in vaccination cannot contribute to the increase of the serocoversion rate. And in order to maximize immunogenicity, more effective vaccines as well as more proper vaccination methods should be used.

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