• Proceedings of the PSK Conference
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• 2002.10a
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• pp.246.2-247
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• 2002

In this study. we tried to investigate whether polymerized basic amino acid e.g. poly-L-lysine(PLL) which has the molecular weight under 10 kD significantly affects the physiological and stimulated mucin release from cultured hamster tracheal surface epithelial cells. Confluent primary hamster tracheal surface epithelial(HTSE) cells were metabolically radiolabeled with 3H-glucosamine for 24 hr and chased for 30 min in the presence of either PLLs or adenosine triphosphate(ATP) and PLL to assess the effects on basic or ATP-stimulated 3H-mucin release. (omitted)

• Environmental Mutagens and Carcinogens
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• v.9 no.1
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• pp.33-46
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• 1989

본 연구는 알킬화제를 처리한 CHO-K1 세포에서 DNA 복제억제와 그 회복과정의 분자론적 기작을 규명할 목적으로 방사선 이중 표지에 의한 DNA 합성율의 측정, 알칼리 자당 농도구배 초원심분리법에 의한 DNA 분자량과 후복제 회복율을 측정하여 다음과 같은 결과를 얻었다. (1) 1mM methyl methanesulfonate (MMS)와 1nM N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) 이하의 낮은 농도의 처리군에서는 DNA 합성율이 급격히 감소하였으나, 2 mM MMS, 2mM MNNG이상의 농도에서는 그 감소양상이 둔화되었다, (2) DNA 합성율은 알킬화제의 처리 직후 감소하였다가 시간경과에 따라 회복되어 처리후 4시간 째에는 대조군 수준 또는 그 이상으로 회복되었다.

• Environmental Analysis Health and Toxicology
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• v.19 no.1
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• pp.93-100
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• 2004

Pretilachlor [2-chloro-N -(2, 6-diethylphenyl)-N-(2-propoxyethyl) acetamide, $C_{17}$H$_{26}$ClNo$_2$, M.W.=311.9, CAS No.51218-49-6]는 제초제의 일종으로 본 연구에서는 박테리아 복귀 돌연변이 시험과 포유동물 세포를 이용한 염색체 이상 시험 및 마우스를 이용한 in vivo소핵 시험을 수행하여 pretilachlor의 유전독성을 평가하였다. 박테리아 복귀 돌연변이 시험에서 pretilachlor는 Salmonella typhimurium TA98, TA 100, TA1535, TA1537 균주의 대사 활성계 존재 및 부재시 313-5,000$\mu\textrm{g}$/plate의 범위에서 농도 의존적인 돌연변이 율의 증가를 관찰할 수 없었다. 또한 포유동물 세포인 Chinese hamster lung (CHL) fibroblast를 이용한 염색체 이상 시험에서 pretilachlor는 대사 활성계 존재 및 부재시 1.56-6.24$\mu\textrm{g}$/mL의 농도에서 clastogenicity를 보이지 않았고, 137.5-550.1 mg/kg의 pretilachlor를 복강 주사한 마우스의 골수세포를 이용한 in vivo소핵 시험의 결과에서도 통계적으로 유의한 소핵 유발능을 관찰할 수 없었다었다

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.188-188
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• 2001

Human cytochrome B5 (CYB5) was coexpressed with cytochrome P450 1A2 (CYP1A2), NADPH-CYP450 reductase (CYPR) and Ν-acetyltransferase 2 (NAT2) in Chinese hamster ovary (CHO) cells. The expression of four proteins was determined by Western blot analyses. The introduction of cDNAs to CHO cells were transduced via retroviral vectors. The cytotoxicity assay of 2-aminoanthracene (2-AA) and aflatoxin B$_1$were approximately 4-fold more sensitive than CYB5 free cells.(omitted)

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.189-189
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• 2001

For a continuous expression of human cytochrome p450 3A5 (CYP3A5) and NADPH-cytochrome P450 reductase (CYPR) proteins, bicistronic construct (CYP3A5BC-LNCX2) was made using internal ribosome entry site (IRES). As for mammalian cell expression, we used pLNCX2 retroviral vector; and using calcium phosphate, plasmid transfer was achieved in 293GPG cell and transduced in Chinese hamster ovary (CHO) cell.(omitted)

• Proceedings of the KSAR Conference
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• 2001.10a
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• pp.55-55
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• 2001

Monosaccaride hexose, may have different role in embryo development of different species. Glucose, fructose and galactose are glycolysible substrates but their effect on embryo development is not identical. Glucose has negative effect to early embryonic stage in several species whereas it is inevitable after compaction. For fructose, it can support blastocyst formation in hamster, mouse and bovine embryo. Effect of galactose is known as detrimental even at a low concentration while glucose has adverse effect only at high concentration in hamster. (omitted)

• YAKHAK HOEJI
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• v.45 no.6
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• pp.708-714
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• 2001

Many studies have provided evidences that hepatitis B surface antigen (HBsAg) including preS region could be an ideal candidate for a new hepatitis B virus (HBV) vaccine with higher efficacy. We established CHO cell lines, IY-CHO-2 and IY-CHO-11 expressing high levels of HBsAg containing preS2 and S protein by stable transfection method. These cell lines expressed the correct size (about 1 kb in length) of HBsAg mRNA as expected. The purified protein from the culture supernatants of the clones showed the same sizes as those expressed in native hepatitis B virus (24 kDa, 27 kDa, 34 kDa and 36 kDa). Antibody productivity of CHO-derived HBsAg protein at lower dose challenge was higher than the protein containing S region alone expressed in yeast system. These results indicate that CHO-derived HBsAg protein containing preS2 and S region can be effectively used for a better immune response as a HBV vaccine.

• Development and Reproduction
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• v.23 no.2
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• pp.101-110
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• 2019

Melatonin is a pineal hormone that is synthesized and released at night under the light and dark cycles of a day. Its effects on the reproductive activities have well been established by the administration through various routes in photoperiodic animals. It was also identified in plants and named phytomelatonin. The capacity of the phytomelatonin was investigated in this investigation whether it affects the reproductive function in male golden hamster. As expected, animals housed in long photoperiod (long photoperiod, LP>12.5 hours of lights in a day) had large testes and animals kept in short photoperiod ($$SP{\leq_-}12.5$$ hours of lights in a day) showed remarkably reduced testes. The dietary supplement with melatonin itself induced the complete involution of testes. Pistachios that were reported to contain a large amount of melatonin demonstrated no effects at all in male golden hamsters. These results suggest that dietary supplement containing melatonin-rich foodstuff used in this investigation may not be enough to affect the reproductive endocrine system in male golden hamsters.

• Proceedings of the Ginseng society Conference
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• 1984.09a
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• pp.75-82
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• 1984

고려인삼은 아시아 지역에서 수세기동안 강장제 및 치료약으로 광범위하게 사용되어 왔으며, 안전성 및 치료약으로서의 가치는 고대 한의서에 잘 명기되어있다. 그러나 근래에 들어서 인삼의 복용이 전세계로 확산됨에 따라 안전성 및 인삼의 약리작용에 대한 정확한 기전이 흥미를 끌게 되었다. 따라서 저자는 Salmonella typhimurium tester strain TA 100과 TA 98 및 V-79 Chinese hamster cell line을 이용하여 고려인삼의 안전성을 확인하기 위하여 본 연구를 수행하였다. 지금가지의 결과는 고려인삼이 안전하다는 것을 시사한다.

• Korean Journal of Agricultural Science
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• v.13 no.1
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• pp.82-89
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• 1986

This experiment was carried out to determine the optimum freezing and thawing rates of the hamster embryos. The female hamsters were induced to superovulate by intraperitoneal injections of 30 i.u. PMSG and mated with males of the same strain of 4 days the PMSG injection. They were killed and embryos were flushed from the oviduct and uterine horn on 3 days after mating. Embryos were flushed with a modified Dulbecco's phosphate-buffered saline and equilibrated with 1.5 M-dimethylsulphoxide by a 3-step procedure. The freezing rates of the samples were $1^{\circ}C/min$ from room temperature to $-6^{\circ}C$ and the samples were seeded at $-6^{\circ}C$. After being held for 3 min at the seeding temperature, the rates were $0.3^{\circ}C/min$ from $-6^{\circ}C$ to $-35^{\circ}C$. From $-35^{\circ}C$ to $-70^{\circ}C$, the rates were divided into $0.1^{\circ}C/min$, $1^{\circ}C/min$ and $10^{\circ}C/min$, respectively. At $-70^{\circ}C$ the samples were plunged directly into liquid nitrogen. The samples were thawed at $4^{\circ}C/min$ and $12^{\circ}C/min$ from $-196^{\circ}C$ to $37^{\circ}C$, and for 2 min in $37^{\circ}C$ water bath, respectively. The average numbers of ovulation points and embryos recovered were 35.1 and 27.0 appearing 77.0% recovery rates. Eight cell embryos in the embryos recovered were 24.8. The survival rates of embryos according to the freezing rates were 55.5~67.7% at $0.1^{\circ}C/min$, 58.8~64.9% at $1^{\circ}C/min$ and 40.5~44.7% at $10^{\circ}C/min$, respectively. The survival rates at $10^{\circ}C/min$ were significantly low. The survival rates of embryos according to the thawing rates were 53.5% at $4^{\circ}C/min$, 53.7% at $12^{\circ}C/min$ and 59.1% in $37^{\circ}C$ water bath. The survival rates, in $37^{\circ}C$ water bath were slightly higher, but we did not find any differences among them. In conclusion, the best freezing rates of hamster embryos were $1^{\circ}C/min$ from the room temperature to $-6^{\circ}C/min$, $0.3^{\circ}C/min$ from $-6^{\circ}C/min$ to $-35^{\circ}C$ and $-0.1^{\circ}C/min$ or $1^{\circ}C/min$ from $-35^{\circ}C$ to $-70^{\circ}C$. The hamster embryos thawed for 2 min in $37^{\circ}C$ water bath showed the best survival rates.