• Toxicological Research
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• 제33권1호
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• pp.43-48
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• 2017

With ultraviolet and visible light exposure, some pharmaceutical substances applied systemically or topically may cause phototoxic skin irritation. The major factor in phototoxicity is the generation of reactive oxygen species (ROS) such as singlet oxygen and superoxide anion that cause oxidative damage to DNA, lipids and proteins. Thus, measuring the generation of ROS can predict the phototoxic potential of a given substance indirectly. For this reason, a standard ROS assay (ROS assay) was developed and validated and provides an alternative method for phototoxicity evaluation. However, negative substances are over-predicted by the assay. Except for ultraviolet A (UVA), other UV ranges are not a major factor in causing phototoxicity and may lead to incorrect labeling of some non-phototoxic substances as being phototoxic in the ROS assay when using a solar simulator. A UVA stimulator is also widely used to evaluate phototoxicity in various test substances. Consequently, we identified the applicability of a UVA simulator to the ROS assay for photoreactivity. In this study, we tested 60 pharmaceutical substances including 50 phototoxins and 10 non-phototoxins to predict their phototoxic potential via the ROS assay with a UVA simulator. Following the ROS protocol, all test substances were dissolved in dimethyl sulfoxide or sodium phosphate buffer. The final concentration of the test solutions in the reaction mixture was 20 to $200{\mu}M$. The exposure was with $2.0{\sim}2.2mW/cm^2$ irradiance and optimization for a relevant dose of UVA was performed. The generation of ROS was compared before and after UVA exposure and was measured by a microplate spectrophotometer. Sensitivity and specificity values were 85.7% and 100.0% respectively, and the accuracy was 88.1%. From this analysis, the ROS assay with a UVA simulator is suitable for testing the photoreactivity and estimating the phototoxic potential of various test pharmaceutical substances.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제20권2호
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• pp.112-126
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• 1998

In dentistry, bony defects can be formed by cyst, tumor, inflammation, trauma and surgery in maxilla and mandible. If the overlying soft tissue invades and preoccupies the jaw bony defects, regenerated bony tissue same as adjacent bone can not replace whole space of the defects, thus preventing osteogenesis from occurring. Guided bone regeneration(GBR) is based on the prevention of overlying soft tissue from entering the bony defect during the initial healing periods. E-polytetrafluoroethylene(e-PTFE) is one of an effective and widely used barrier membrane for GBR, but it has the disadvantages such as surgical removal and high price. To overcome such disadvantages of e-PTFE, many investigators have proposed various absorbable barrier membranes. Inexpensive oxidized cellulose($Surgicel^{(R)}$) membrane was shown to have potential for use as an absorbable barrier membrane for regenerative procedure and it would not require surgical removal. The purpose of this study is to investigate the absorption periods of oxidized cellulose at the implant site and usefulness as a mechanical barrier, preventing the ingrowth of the overlying soft tissue into the bony defects. Two bony defects were made in each tibia of a dog using drill and one defect covered with oxidized cellulose and the other covered with periosteum directly as control. The experimental animals were sacrificed at 1st-7th, 10th, 14th, 21th, 28th day postoperatively, Inspection of the specimens was done to evaluate gross changes. Specimens were examined histopathologically by hematoxylin-eosin and Masson's trichrome staining under light microscope. The results were as follows : 1. There was no significant differences of inflammatory reaction between the experimental and the control group. 2. The resorption of oxidized cellulose was almost completed within 14th day. 3. Histologically, bone formation in the experimental group was somewhat more than that of the control group at 10th, 14th, 21th and 28th day postoperatively. The bone forming pattern of the experimental group was more regular than that of the control group. 4. There was no evidence of soft tissue invasion into the bony defect in the experimental group. In conclusion, oxidized cellulose membrane might be used as an alternative absorbable barrier membrane to prevent overlying soft tissue invasion into the bony defects.

• 한국가금학회지
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• 제40권4호
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• pp.379-388
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• 2013

Avian paramyxovirus (APMV) type 4 and 6 were isolated during an avian influenza (AI) surveillance program of wild birds. This study also conducted experimental infection of wild-bird-origin APMV type 4 and 6 in specific pathogen free (SPF) chickens to study pathogenicity and transmission within domestic flocks. In addition, serological prevalence data of APMV type 4 and 6 in domestic fowls was conducted with chicken sera collected from 2007 to 2009 in order to understand infection status. The results of the animal experiment showed that APMV type 4 and 6 had the ability to infect chickens with sero-conversion and to transmit the virus from infected birds to contacted birds, but showed low pathogenicity. Serological tests revealed that APMV type 4 was widespread in the poultry industry, especially in layer flocks, but the positive rate for APMV type 6 was very low. This study concluded that wild bird-origin APMV type 4 and 6 could infect the chickens by inter-species transmission and the seroprevalence of APMV type 4 was quite high in Korean poultry. However, since almost all the chicken flocks had a high level of antibody titer against APMV type 1, there was possibility of cross reaction between APMV type 1 and 4, which made the interpretations more complicated. In order to understand infection status in the natural environment, additional study is necessary regarding the seroprevalence of APMV type 4 and 6 in the wild bird population.

• BMB Reports
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• 제45권2호
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• pp.79-84
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• 2012

In asthma, T helper 2 (TH2)-type cytokines such as interleukin (IL)-4, IL-5, and IL-13 are produced by activated $CD^{4+}$ T cells. Dendritic cells played an important role in determining the fate of naive T cells into either $T_H1$ or $T_H2$ cells. We determined whether RG-II regulates the $T_H1/T_H2$ immune response by using an ovalbumin-induced murine model of asthma. RG-II reduced IL-4 production but increased interferon-gamma production, and inhibited GATA-3 gene expression. RG-II also inhibited asthmatic reactions including an increase in the number of eosinophils in bronchoalveolar lavage fluid, an increase in inflammatory cell infiltration in lung tissues, airway luminal narrowing, and airway hyperresponsiveness. This study provides evidence that RG-II plays a critical role in ameliorating the pathogenic process of asthmatic inflammation in mice. These findings provide new insights into the immunotherapeutic role of RG-II in terms of its effects in a murine model of asthma.

• Journal of Preventive Medicine and Public Health
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• 제28권2호
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• pp.526-541
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• 1995

This study was conducted to estimate the validity of reverse transcriptase-polymerase chain reaction(RT-PCR) compared to enzyme immunoassay(EIA) for the detection of hepatitis C virus (HCV) infection. EIA for antibody to HCV(anti-HCV) and RT-PCR for HCV was executed on the subjects from Pusan and Kyungnam area with questionnaire survey to collect some relating factors of HCV infection. As the result from 617 cases, the prevalence of HCV infection was 1.5% by EIA and 3.7% by RT-PCR(p<0.05), and the age standardized rate was 1.7% and 3.4% by EIA and RT-PCR, respectively. The prevalence of hepatitis B surface antigen(HBsAg) was 6.8% by enzyme linked immunosorbent assay(ELISA) and the age standardized rate was 7.7%. It was the higher in male group comparing to female group(p<0.01). Both of the prevalence of HCV and HBsAg were higher in elevated asparate aminotransferase(AST) and alanine aminotransferase (ALT) group than in normal AST and ALT group(p<0.01). There was no specific risk factor of HCV infection. Though the degree of agreement of EIA and RT-PCR by gamma statistics was 97.2%, it showed a significant difference between the two methods(p<0.01). For the detection of HCV infection, positive predictive value of EIA was 66.7% and negative predictive value of EIA was 97.2%. This study suggests that negative result to anti-HCV by EIA didn't mean the free state of HCV infection, therefore it would be helpful that further monitoring for HCV infection by RT-PCR in the case of elevated AST and ALT and/or clinically suspected.

• Asian Pacific Journal of Cancer Prevention
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• 제14권12호
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• pp.7165-7169
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• 2013

Purpose: The aim of this study was to evaluate any association of GSTM1 and GSTT1 null genotypes with the risk of lung cancer in a South Korean population. Methods: We conducted a large-scale, population-based case-control study including 3,933 lung cancer cases and 1,699 controls. Genotypes of GSTM1 and GSTT1 were determined using real-time polymerase chain reaction. Results: In logistic regression analysis adjusted for age and smoking, we did not find any association between GSTM1 or GSTT1 and LC risk in women. However, in men, the GSTM1 and GSTTI null genotypes were borderline associated with risk (OR=1.18, 95% CI=0.99-1.41 for GSTM1, OR=1.18, 95% CI=0.99-1.41 for GSTT1), and combined GSTM1 and GSTT1 null genotypes conferred an increased risk for LC in men (OR=1.39, 95% CI=1.08-1.78). The OR for the GSTT1 null genotype was greater in subjects aged 55 years old or younger (OR=1.45, 95% CI=1.09-1.92 for men; OR=1.36, 95% CI=0.97-1.90 for women), than in those over age 55 (OR=1.03, 95% CI=0.83-1.27 for men; OR=0.86, 95% CI=0.66-1.12 for women) in both genders (p for interaction <0.05). Conclusions: In the Korean population, the GSTM1 and GSTT1 null genotypes are risk factors for LC in men; the GSTT1 null genotype has a more prominent effect on LC risk in younger people (age 55 years and under) than in older individuals.

• 대한환경공학회지
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• 제32권3호
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• pp.256-263
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• 2010

본 논문은 염분농도가 호기성 생분해도에 미치는 영향을 파악하고, 그 결과를 수산물 가중 폐수 처리 위한 기초자료로 사용하기 위하여 수행되었다. $Cl^-$농도(1,400~18,000 mg/L)에 따른 유기물 제거효율 검토결과, $Cl^-$ 6,000 mg/L 이하에서 미생물들은 염분에 적응하였으나 $Cl^-$ 12,000 mg/L 이상에서는 반응시간이 길어져도 처리효율이 개선되지 않는 것으로 조사되었다. 생물학적 분해불가능한 용존성 유기물 함유계수 $Y_I$와 미생물 신진대사에 의한 inert 물질 생성계수 Yp는 염분농도가 증가할수록 증가하였으며, $Cl^-$ 농도(0~18,000 mg/L)에 따른 용존성 유기물 비율은 10.8~13.1%로, 미생물 신진대사에 의한 inert 물질 생성비율은 7.0~24.6%로 조사되었다. $NH_3$-N 제거효율은, 원폐수는 HRT 18 hr에서 96.2%의 제거효율을 보였으나, $Cl^-$ 6,000 mg/L, HRT 22 hr에서 96.5%, $Cl^-$ 12,000 mg/L, HRT 30 hr에서 90.2%, $Cl^-$ 18,000 mg/L, HRT 45 hr에서 90.3%의 제거효율을 나타내, 질산화 과정이 유기물 제거 보다 염분농도에 더 민감한 것으로 조사되었으며, 폐수내 $Cl^-$ 6,000 mg/L 이상부터는 $NO_2$-N에서 $NO_3$-N로의 전환율도 낮게 조사되었다.

• 한국균학회지
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• 제22권2호
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• pp.130-137
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• 1994

담자균류인 잿빛 만가닥버섯 Lyophyllum decastes은 이미 항암작용이 있다고 보고된 바, 이 버섯의 유전연구와 균주개발을 위해 기초적 연구인 원형질체 분리와 재생에 관하여 실험하였다. 원형질체 분리의 최적 조건으로는 여러 효소의 혼용보다 Novozym 234(10 mg/ml)를 단용하였을 때 더 우수하였고, 삼투압 안정제로 0.6 M $MgSO_4$에서 효과적이었으며, $24^{\circ}C$ 에서 5일 배양한 균사와 효소액을 4시간 반응 시켰을 때 수득율이 높았다. 완충용액과 pH는 Na-phosphate buffer(pH 4)에서 원형질체 분리가 양호 하였으며, 고체배지보다 액체배지에서 자란 균사를 완충용액과 pH를 조절하지 않은 상태에서 효소와 반응시켰을 때 $12.5{\times}10^6\;cell/ml$로 높았다. 원형질체 재생시 균사가 배지 전면에 확산되어 성장하여 성장억제제로 Triton X-100(0.0025%)을 사용하였다. 원형질체 분리시와는 대조적으로 0.6M sucrose와 mannitol에서 재생이 효율적이었고, 각각 8.32%와 5.94%의 재생 빈도를 나타내었다.

• IMMUNE NETWORK
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• 제12권2호
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• pp.58-65
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• 2012

Background: A cell line with transfected Wilms' tumor protein 1 (WT1) is has been used for the preclinical evaluation of novel treatment strategies of WT1 immunotherapy for leukemia due to the lack of appropriate murine leukemia cell line with endogenous WT1. However, silencing of the transgene occurs. Regarding the effects of hypomethylating agents (HMAs) on reactivation of silenced genes, HMAs are considered to be immune enhancers. Methods: We treated murine WT1- transfected C1498 (mWT1-C1498) with increasing doses of decitabine (DAC) and azacitidine (AZA) to analyze their effects on transgene reactivation. Results: DAC and AZA decreased the number of viable cells in a dose- or time-dependent manner. Quantification of WT1 mRNA level was analyzed by real-time polymerase chain reaction after mWT1-C1498 treated with increasing dose of HMA. DAC treatment for 48 h induced 1.4-, 14.6-, and 15.5-fold increment of WT1 mRNA level, compared to untreated sample, at 0.1, 1, and $10{\mu}M$, respectively. Further increment of WT1 expression in the presence of 1 and $10{\mu}M$ DAC was evident at 72 h. AZA treatment also induced up-regulation of mRNA, but not to the same degree as with DAC treatment. The correlation between the incremental increases in WT1 mRNA by DAC was confirmed by Western blot and concomitant down-regulation of WT1 promoter methylation was revealed. Conclusion: The in vitro data show that HMA can induce reactivation of WT1 transgene and that DAC is more effective, at least in mWT1-C1498 cells, which suggests that the combination of DAC and mWT1-C1498 can be used for the development of the experimental model of HMA-combined WT1 immunotherapy targeting leukemia.

• 농촌의학ㆍ지역보건
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• 제12권1호
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• pp.117-123
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• 1987

Detection of IgG antibody in clonorchiasis has been accomplished through various serodiagnostic procedure including complement fixation test, gel diffusion test, indirect fluorescent antibody test, indirect hemagglutination test etc. In this report enzyme immunoassay (ELISA) and indirect hemagglutination test (IHA) were used to determine IgG serum antibody levels before and after therapy with praziquantel. Briefly, sera from 62 cases of confirmed human clonorchiasis were examined before and after treatment with praziquantel. Among 62 cases treated 25 cases were categorized as completely cured groups by formalin-ether and careful examination of 4 cellophane thick smered slides at 18 months after treatment. The sera of 25 cases of cured groups were examined again by ELISA and IHA, and com-pared to the previous data. The results obtained were as follows; 1) Sensitivity of IHA test was 83.6% when cut-off titer of 1:8 was applied. No sera obtained from 10 normal healthy control showed positive reaction. 2) Twenty cases (80.0%) out of 25 cured one showed negative results by IHA at 18 months after treatment. 3) Although 5 cases showed positive titer even 18 months after treatment 3 cases of them showed decreased antibody titer. However 2 cases did not show any response. 4) Even though almost all cases showed de- creased ELISA value, only 11 cases (44.0%) out of 25 patients showed negative results by ELISA at 18 months after treatment. In conclusion, it is suggested that, while IgG ELISA for detecting long persisting antibody was more sensitive than IHA, IHA results more conclusively indicated effective treatment in clonorchiasis by negative conversion than did the results of ELISA.