• Asian Pacific Journal of Cancer Prevention
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• 제17권4호
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• pp.1773-1777
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• 2016

Diagnostic and therapeutic radiation fields are planned so as to reduce side-effects while maximising the dose to site but effects on healthy tissues are inevitable. Radiation causes strand breaks in DNA of exposed cells which can lead to chromosomal aberrations and cause malfunction and cell death. Several researchers have highlighted the damaging effects of high dose radiation but still there is a lacuna in identifying damage due to low dose radiation used for diagnostic purposes. Blood is an easy resource to study genotoxicity and to estimate the effects of radiation. The micronucleus assay and chromosomal aberration can indicate genetic damage and our present aim was to establish these with lymphocytes in an in vitro model to predict the immediate effects low dose radiation. Blood was collected from healthy individuals and divided into 6 groups with increasing radiation dose i.e., 0Gy, 0.10Gy, 0.25Gy, 0.50Gy, 1Gy and 2Gy. The samples were irradiated in duplicates using a LINAC in the radiation oncology department. Standard protocols were applied for chromosomal aberration and micronucleus assays. Metaphases were stained in Giemsa and 200 were scored per sample for the detection of dicentric or acentric forms. For micronuclei detection, 200 metaphases. Giemsa stained binucleate cells per sample were analysed for any abnormality. The micronuclei (MN) frequency was increased in cells exposed to the entire range of doses (0.1-2Gy) delivered. Controls showed minimal MN formation ($2.0%{\pm}0.05$) with triple MN ($5.6%{\pm}2.0$) frequency at the lowest dose. MN formation increased exponentially with the radiation dose thereafter with a maximum at 2Gy. Significantly elevated numbers of dicentric chromosomes were also observed, even at doses of 0.1-0.5Gy, compared to controls, and acentric chromosomes were apparent at 2Gy. In conclusion we can state that lymphocytes can be effectively used to study direct effect of low dose radiation.

• 한국산학기술학회논문지
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• 제13권8호
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• pp.3532-3536
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• 2012

난자 세포의 정상적인 성숙과정을 이해하려면 모계유래 유전자 발현 증가의 분자 생물학적 기전을 밝혀내야 한다. 이것은 모계 유전자의 염기서열의 변화와 밀접한 관계가 있다. 전 연구결과에 의하면 돼지 난자 체외 성숙과정에서의 모계 유전자 mRNA 발현은 통상적으로 poly(A) 꼬리 길이와 아데닐산 중합반응에 의하여 검증된다. 하지만 포유동물 체외성숙 과정에서는 아직까지 밝혀진 것이 없다. 따라서 본 연구목적은 성숙단계 난모세포에서의 분자생물학적 기전을 해명하고자, 4개의 중요한 모계유전자발현을 real-time PCR기법으로 확인하여 poly(A) 꼬리 길이와 아데닐산중합반응의 변화를 확인하였다. 본 연구에서 접합체 유전자 활성화 단계에서 모계 유전자의 비정상적인 발현과 이것에 상응하는 단백질 수준의 억제는 일부 혹은 대부분 유전자 손실에 의하여 초래된 것임을 알 수 있었다. 따라서 이상적인 모계 유전자 발현은 난자 세포의 성숙 및 더 나가서 초기 배아 발달에 중요한 역할을 하는 것임을 확인 하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권5호
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• pp.3001-3003
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• 2013

Objective: Spleen tyrosine kinase (Syk) is closely related to tumor invasion and metastasis, and has been shown to have potential inhibitory effects in tumors. In this study, we constructed a eukaryotic expression vector for Syk and analyzed its effects on invasive ability of the A549 non-small cell lung cancer cell line in vitro. Methods: A fragment of Syk was obtained by RT-PCR from human lung cancer cells and cloned into the expression vector pLNCXSyk. After restriction endonuclease digestion, PCR and DNA sequencing confirmation, the recombinant Syk expression plasmid was transfected into A549 human lung cancer cells using lipofectamine protocols. After selection, the cells stably expressed Syk. Detection of Syk expression of the cells by RT-PCR, and invasive ability were examined. Results: The eukaryotic expression plamid pLNCXSyk was constructed and expressed stably in the A549 human lung cancer cells. The RT-PCR results showed that Syk mRNA expression was upregulated significantly (P<0.05). Lower invasion through a basal membrane were apparent after transfection (P<0.05). Conclusions: A eukaryotic expression plasmid to cause Syk expression in lung cancer cells can obviously inhibit their invasive ability in vitro.

• 동의생리병리학회지
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• 제27권6호
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• pp.752-758
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• 2013

Estrogen like activities were evaluated using ethanol and hot water extracts of herbal medicines by using an in vitro detection system. Bokryung (Poria cocos), Sanyak (root of Dioscorea batatas) and Mokdanpi (root skin of Paeonia suffruticosa) represented statistically significant estrogen-like activities (p<0.001), while Omija (fruit of Schizandra chinensis), Taeksa (root of Alisma canaliculatum A. BR.), Jihwang (root of Rhemannia glutinosa), and Sansuyu (fruit of Cornus officinalis) did not. Estrogen-like activities of Bokryung hot water extract (500 ${\mu}g/ml$) and ethanol extract (50 ${\mu}g/ml$) were almost same as that of a C M $17{\beta}$-estradiol. Furthermore, estrogen-like activities of ethanol extracts (500 ${\mu}g/ml$) of Bokryung and Mokdanpi were stronger than that of $10^{-7}$ M $17{\beta}$-estradiol. These results suggest that Bokryung, Sanyak and Mokdanpi show estrogen-like activities. Especially, Sanyak and Mokdanpi represented promotive effect on the proliferation of MC3T3-E1 osteoblastic cells. Bokryung, Sanyak and Mokdanpi also exhibited superior inhibitory effect on the viability of RAW 264.7 cells. In conclusion, these three herbal medicines might be interpreted as candidates for the further study or development of functional foods or medicine to prevent or avoid postmenopausal symptoms of women.

• BMB Reports
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• 제35권2호
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• pp.206-212
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• 2002

The NS2B-NS3(pro) polyprotein segment from the dengue virus serotype 2 strain 16681 was purified from overexpressing E. coli by metal chelate affinity chromatography and gel filtration. Enzymatic activity of the refolded NS2B-NS3(pro) protease complex was determined in vitro with dansyl-labeled peptide substrates, based upon native dengue virus type 2 cleavage sites. The 12mer substrate peptides and the cleavage products could be separated by reversed-phase HPLC, and were identified by UV and fluorescence detection. All of the peptide substrates (representing the DEN polyprotein junction sequences at the NS2A/NS2B, NS2B/NS3, NS3/NS4A and NS4B/NS5 sites) were cleaved by the recombinant protease NS2B-NS3(pro). No cleavage was observed with an enzymatically inactive S135A mutant of the NS3 protein, or with a modified substrate peptide of the NS3/NS4A polyprotein site that contained a K2093A substitution. Enzymatic activity was dependent on the salt concentration. A 50% decrease of activity was observed in the presence of 0.1M sodium chloride. Our results show that the NS3 protease activity of the refolded NS2B-NS3(pro) protein can be assayed in vitro with high specificity by using cleavage-junction derived peptide substrates.

• 한국패류학회지
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• 제27권4호
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• pp.387-393
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• 2011

The objective of this study was to develop a real-time PCR method for the rapid detection and quantification of the protozoan pathogen Perkinsus olseni using a TaqMan probe. For the standard, genomic DNA was extracted from $10^5$ in vitro-cultured P. olseni trophozoites, and then 10-fold serial dilutions to the level of a single cell were prepared. To test the reliability of the technique, triplicates of genomic DNA were extracted from $5{\times}10^4$ cells and 10-fold serial dilutions to the level of 5 cells were prepared. The standards and samples were analyzed in duplicate using an $Exicycler^{TM}$ 96 real-time quantitative thermal block. For quantification, the threshold cycle ($C_T$) values of samples were compared with those obtained from standard dilutions. There was a strong linear relationship between the $C_T$ value and the log concentration of cells in the standard ($r^2$ = 0.996). Detection of DNA at a concentration as low as the equivalent of a single cell showed that the assay was sensitive enough to detect a single cell of P. olseni. The estimated number of P. olseni cells was similar to the original cell concentrations, indicating the reliability of P. olseni quantification by real-time PCR. Accordingly, the designed primers and probe may be used for the rapid detection and quantification of P. olseni from clam tissue, environmental water, and sediment samples.

• 한국의학물리학회지:의학물리
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• 제9권2호
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• pp.115-121
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• 1998

본 연구는 암을 조기진단을 위한 장치개발의 기초 연구로서, 질병(암)을 검출할수 있는 광 특성의 존재를 결정하기 위하여 12개 생체조직의 계층별 시료와 인체의 혈액에서 광 특성을 측정하였다. 실험은 동물의 지방 및 근육 조직과 인체 혈액 HCT의 27.3%, 35.4%, 45.6%과 59.1%을 대상으로, 광파장이 630nm, 660nm, 780nm, 880nm, 940nm 에서 흡수 계수, $\mu$$_{\alpha}$를 측정하였다. 측정된 흡수계수는 일정하고 특이한 변화를 보여 주었다. 본 연구의 결과에 의하면 생체조직의 계층별과 광파장의 특정 파장대에서 분명한 차이를 구분할 수 있었다. 차이를 구분할 수 있었다.

• 한국동물위생학회지
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• 제24권1호
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• pp.43-50
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• 2001

Swine proliferative enteritis(SPE) caused by inかsoma intracellularis is a common enteric disaese of grower and finisher pig. Swine affected with SPE show variable clinical signs including diarrhea, weight loss, aberrant growth and death. The characteristic lesion of ileitis at necropsy is marked thickening of the last section of the small intestine. The inner lining of the thickened intestine proliferates almost like a cancer and curved rod bacteria(L intracellularis) are always seen inside the intestinal wall. Infected swine shed the organism in the feces. Isolation and growth of pure L intracellularis in vitro requires a suitable cell culture. This procedure is difficult and not a practical means of diagnosis, thus the polymerase chain reaction(PCR) test of feces can be used to determine whether a pig is shedding the infective organism. A sensitive assay based on amplification of a 319bp DffA fragment of the L intracellularis of Swine proliferative enteritis was attempted for the detection of the organism in the 62 feces of swine. L intracellularis was identified on three herds and detected in 6 fecal samples, representing a infection rate of 9.7%. The PCR was very sensitive and specific on the individual level. The PCR technique could be very useful for the diagnosis of this disease.

• 한국수정란이식학회지
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• 제20권2호
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• pp.169-176
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• 2005

수정란의 성 판별은 유전적으로 우수한 유전형질을 보유하고 있는 소의 수정란을 성 판별하므로서 희망하는 성의 송아지를 생산할 수 있으며, 부가가치가 높은 수정란을 확보할 수 있는 기술이다. 수정란의 손상을 최소화하면서 할구를 biopsy하는 기술을 개발하고, 간단하고 빠른 시간에 성 판별이 가능한 Loop-mediated isothermal amplification방법으로 수정란을 성 판별을 실시한 결과는 다음과 같다. 1. 한우 체내 수정란의 성비는 암컷이 $56.5\%$, 수컷이 $43.5\%$였고, 체외 수정란은 암컷이 $49.2\%$, 수컷이 $33.9\%$였다. 그리고, 젖소 체외 수정란의 성비는 암컷이 $29.2\%$, 수컷이 $70.8\%$를 나타내어 한우 체내 및 체외 수정란보다 젖소 체외수정란의 수컷비율이 유의적으로 높게 나타내었다(p<0.05). 또한, 한우 체외 수정란에서 성 판별이 불가능한 것이 $16.9\%$를 나타내어 한우 체내 수정란 및 젖소 체외 수정란과는 유의적인 차이를 나타내었다.(P<0.05). 2. Biopsy한 체내 수정란의 체외 발달율은 $100\%$였으나 체외 수정란에서는 정상적으로 발달하지 못하고 퇴화된 수정란이 $13.2\%$로 체내 수정란보다 유의적으로 높은 결과를 나타내었다.(P<0.05). 3. Punching 방법으로 수정란의 biopsy 후 정상적으로 발달하지 못하고 퇴화된 수정란은 체내 및 체외 수정란에서는 없었으나 biopsy 방법으로 biopsy한 수정란은 체내 및 체외 수정란에서 각각 $16.7\%$ 및 $22.6\%$를 나타내어 Punching 방법보다 유의적으로 높은 결과를 나타내었다(P<0.05). 이상의 결과로 보아 한우 체내 수정란은 LAMP방법을 이용하여 간단하고 신속하게 성 판별이 가능하며, 수정란의 biopsy는 punching 방법이 수정란에 손상을 적게 주는 것으로 사료된다.

• Journal of Veterinary Science
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• 제21권5호
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• pp.71.1-71.10
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• 2020

Background: Feline calicivirus (FCV) is a major and highly infectious pathogen in cats worldwide. However, there have been limited studies about the status of FCV infections in Korea. Objectives: To investigate the current status of FCV infections in stray cats in Korea. Methods: A novel reverse transcription polymerase chain reaction (RT-PCR) assay was developed based on the conserved nucleotide sequences of reported FCV strains. Field swab samples were collected from 122 cats (2 hospital admitted cats and 120 stray cats) in 2016 and 2017. All the samples were tested by virus isolation and 2 different RT-PCRs, including the novel RT-PCR, for the detection of FCV. Results: The novel RT-PCR assay showed no cross-reactivity to the nucleic acids of the other feline pathogens tested, and the limit of detection was calculated as 10⁰ TCID₅₀/mL based on an in vitro assessment. The novel RT-PCR assay detected 5 positive samples from the 122 field samples, which showed perfect agreement with the results of the virus isolation method. In contrast, another RT-PCR assay used in a previous study in Korea detected no positive samples. The prevalence of FCV infection in stray cats was 2.5% (3/120) based on the results of virus isolation and the novel RT-PCR assays. Conclusions: The current study is the first report of the detection and prevalence of FCV in stray cats in Korea. The novel RT-PCR assay developed in this study showed high sensitivity and specificity, which indicates a useful diagnostic assay to identify FCV infection in cats.