• Archives of Pharmacal Research
• /
• v.18 no.4
• /
• pp.243-248
• /
• 1995

Seventeen transformation-deficient mutants of streptococcus pneumoniae, which are defective in competence induction (com), DNA uptake(ent) of recombination(rec), were investigated to determine sensitivity to ethylmethane sulfonate(EMS), methylmethane sulfonate(MMS), UV and mitomycin C. In ethylmethane sulfonate assay, the viability of most $com^-, \; rec^-\; and ent^-$ mutants was decreased about 2-10 times and the viability of ent-9 and ent-13 mutant was decreased about 33 and 25 times, respectively. On the other hand only half of the transformation-deficient mutants tested was sensitive to methylmethane sulfonate about 2 times and ent-12 mutant was sensitive to 2.0% MMS about 8 times. After UV and mitomycin C treatment, most of the mutants are not sensitive to UV and mitomycin C, although the viability of some transformation-deficient mutants was decreased slightly. Especially none of the com mutants were sensitive to DNA damage suggesting that competence is not involved in DNA repair. Also DNA uptake and recombination gane might be related to DNA repair function.

• Korean Journal of Environmental Biology
• /
• v.29 no.3
• /
• pp.236-240
• /
• 2011

Mercury known as quicksilver, is the most common cause of heavy metal toxicity. Toxicity caused by excessive mercury exposure is now being recognized as a widespread environmental problem and is continuing to attract a great deal of public concerns. The mercury genotoxicity could be its effect on DNA repair mechanisms, which constitute the defense system designated to protect genome integrity. The objective of this study is to confirm that mercuric chloride inhibits the repair of gamma ray-induced DNA damage. The earthworm of Eisenia fetida was chosen for this study because it is an internationally accepted model species for toxicity testing with a cosmopolitan distribution. Experiments were done to identify the levels of DNA damage and the repair kinetics in the coelomocytes of E. fetida irradiated with 20 Gy gamma rays alone or with gamma rays after 40 mg $kg^{-1}$ $HgCl_2$ treatment by means of the single cell gel electrophoresis assay. The Olive tail moments were measured during 0~96 hours after irradiation. The repair time in the animals treated with the combination of $HgCl_2$ and ionizing radiation was nearly five times longer than that in the animals treated with ionizing radiation alone. Also, E. fetida exposed to mercury showed a statistically lower repair efficiency of gamma ray-induced DNA damage. The results suggest that the mercury could even have deleterious effects on the DNA repair system. Influence of mercury on the DNA repair mechanisms has been confirmed by this study.

• The Microorganisms and Industry
• /
• v.15 no.2
• /
• pp.24-28
• /
• 1989

폐염균의 특징은 폐염, 류마티스성 심장병, 수막염 등의 질병을 일으키는 병원균이라는 것과 아주 높은 효율로 형질전환을 할 수 있다는 사실이다 ($10^{8}$ 개의 균에 염색체 DNA 1.mu.g을 써서 실험하였을 때 $10^{6}$개의 transformant를 얻을 수 있음). 폐염균이 자연상태에서 이렇게 높은 효율의 형질전환을 할 수 있는 이유는 정상생리의 일부로서 형질전환에 관계된 유전자가 형질전환을 할때 발현되기 때문이다. 그러나 폐염균 형질전환에 대한 연구는 아직도 초기단계라고 할 수 있으며 그 이유는 현재 전세계적으로 극소수의 연구자들만이 연구를 수행하고 있기 때문이다. 즉, 미국 Brookhaven National Laboratory의 Lacks와 프랑스 CNRS의 Claverys는 mismatch repair에 대한 연구를, Illinois 대학의 Morrison은 competence에 대해, 미국 Rockefeller 대학의 Hotchkiss와 Tomasz는 DNA binding을 연구하고 있을 뿐이다. 본 논고에서는 폐염균 형질전환에 대해 지금까지의 연구 상태와 문제점, recP의 클로닝에 대해 소개하고자 한다.

• Journal of Gynecologic Oncology
• /
• v.29 no.6
• /
• pp.93.1-93.11
• /
• 2018

The introduction of checkpoint inhibitors revolutionized immuno-oncology. The efficacy of traditional immunotherapeutics, like vaccines and immunostimulants was very limited due to persistent immune-escape strategies of cancer cells. Checkpoint inhibitors target these escape mechanisms and re-direct the immune system to anti-tumor toxicity. Phenomenal results have been reported in entities like melanoma, where no other therapy was able to demonstrate survival benefit, before the introduction of immunotherapeutics. The first experience in ovarian cancer (OC) was reported for nivolumab, a fully human anti-programmed cell death protein 1 (PD1) antibody, in 2015. While the data are extraordinary for a mono-immunotherapeutic agent and very promising, they do not match up to the revolutionary results in entities like melanoma. The key to exceptional treatment response in OC, could be the identification of the most immunogenic patients. We hypothyse that BRCA mutation could be a predictor of improved response in OC. The underlying DNA-repair-deficiancy should result in increased immunogenicity because of higher mutational load and more neoantigen presentation. This hypothesis was not tested to date and should be subject to future trials. The present article gives an overview of the immunologic background of checkpoint inhibition (CI). It presents current data on nivolumab and other checkpoint-inhibitors in solid tumors and OC specifically and depicts important topics in the management of this novel substance group, such as side effect control, diagnostic PD-1/programmed cell death-ligand 1 (PD-L1) expression assessment and management of pseudoprogression.

• The Journal of Korean Obstetrics and Gynecology
• /
• v.20 no.4
• /
• pp.1-23
• /
• 2007

Purpose: These experiments were undertaken to evaluate the effect of Onpoeum on ovarian functions and differential gone expressions related with cell viabilities caspase-3, MAPK and MPG in female mice. Methods: We administered the Onpoeum to 6-week-old female ICR mice for 4, 8, or 12 days. With different concentration of Onpoeum, the female mice were injected PMSG and hCG for ovarian hyperstimulation. The mice divided into 3 different groups for each experiment. We chose the Caspase-3 for cell apoptosis, MAPK and MPG genes for cell viability and DNA repair. Results: In case of 4, 8, 12 day of Onpoeum, we were examined the mean number of total ovulated oocytes and the number of morphologically normal oocytes. We were also examined the embryonic developmental competence in vitro. In audition we were examined the differential expression of cell apoptosis, viability and DNA repair related genes, Caspase-3, MAPK and MPG according to concentration and duration of Onpoeum. From these results showed that the administration of Onpoeum played a role of prevention of cell apoptosis and DNA damages and also increased cell proliferation resulted in ovarian functions. Conclusion: It is suggested that the medication of Onpoeum may have beneficial effect on reproductive functions of female mice via prevention of cell apoptosis and DNA damaging and promotion of cell proliferation.

• The Journal of Korean Obstetrics and Gynecology
• /
• v.21 no.1
• /
• pp.257-266
• /
• 2008

Purpose: These experiments were undertaken to evaluate the effect of Onpoeum on ovarian functions and differential gene expressions related with cell viabilities caspase-3, MAPK and MPG in female mice. Methods: We administered the Onpoeum to 6-week-old female ICR mice for 4, 8, or 12 days. With different concentration of Onpoeum, the female mice were injected PMSG and hCG for ovarian hyperstimulation. The mice divided into 3 different groups for each experiment. We chose the Caspase-3 for cell apoptosis, MAPK and MPG genes for cell viability and DNA repair. Results: In case of 4, 8, 12 day of Onpoeum, we were examined the mean number of total ovulated oocytes and the number of morphologically normal oocytes. We were also examined the embryonic developmental competence in vitro. In addition we were examined the differential expression of cell apoptosis, viability and DNA repair related genes, Caspase-3, MAPK and MPG according to concentration and duration of Onpoeum. From these results showed that the administration of Onpoeum played a role of prevention of cell apoptosis and DNA damages and also increased cell proliferation resulted in ovarian functions. Conclusions: It is suggested that the medication of Onpoeum may have beneficial effect on reproductive functions of female mice via prevention of cell apoptosis and DNA damaging and promotion of cell proliferation.

• The Journal of Korean Obstetrics and Gynecology
• /
• v.20 no.3
• /
• pp.91-110
• /
• 2007

Purpose : These experiments were undertaken to evaluate the effect of administration of Palmultang on ovarian functions and differential gene expressions related cell viabilities caspase-3, MAPK and MPG in female mice. Materials and Methods : We administered the Palmultang to 6-week-old female ICR mice for 4, 8, or 12 days. The female mice were injected PMSG and hCG for ovarian hyperstimulation. And then recovered ovaries were minced and extracted mRNA and analyzed cell viability related gene expression. We chose the caspase-3 for cell apoptosis, MAPK and MPG genes for cell viability and DNA repair. To compare the differences, we set a control group treated with plain water at the same volume by the same way. Results : In case of administration of Palmultang, the mean number of total ovulated oocytes and the number of morphologically normal oocytes increased significantly compared to a control group. We were also examined the embryonic developmental competence in vitro. The administration of Palmultang in a concentration with 10 and 100 mg/ml were beneficial effect of embryonic development in preimplantation period. The administration of Palmultang play a role of prevention of cell apoptosis and DNA damages and also increased cell proliferation resulted in ovarian functions. Conclusion : From our results suggested that the medication of Palmultang has beneficial effect on reproductive functions of female mice via prevention of cell apoptosis and DNA damaging and promotion of cell proliferation.

• The Journal of Korean Obstetrics and Gynecology
• /
• v.22 no.2
• /
• pp.60-78
• /
• 2009

Purpose: These experiments were undertaken to evaluate the effect of administration of Evodiae Fructus on ovarian functions and differential gene expressions related caspase-3, MAPK and MPG in female mice. Methods: We administered the Evodiae Fructus to 6-week-old female ICR mice for 4, 8, or 12 days. With different concentration of Evodiae Fructus, the female mice were injected PMSG and hCG for ovarian hyperstimulation. The mice divided into 3 groups for each experiment. We chose the caspase-3 for cell apoptosis, MAPK and MPG genes for cell viability and DNA repair. Results: In case of 4, 8, 12 day of Evodiae Fructus, we were examined the mean number of total ovulated oocytes and the number of morphologically normal oocytes. We were also examined the embryonic developmental competence in vitro. In addition we were also examined the differential expression of cell viability related genes, caspase-3, MAPK and MPG according to concentration and duration of Evodiae Fructus administration. MPG gene expressions for cell viability and DNA repaie were increased in dose dependent manner than that of control group in 4-day administration group. Conclusion: It is suggested that the medication of Evodiae Fructus has beneficial effect on reproductive functions of female mice via promotion of cell proliferation.