• Korean Journal of Plant Tissue Culture
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• v.26 no.3
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• pp.183-187
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• 1999

To establish an efficient screening system for new herbicides using plant cultured cells, responses of tobacco photomixotrophic cultured (PH) cells to various herbicides with different modes of action were surveyed by measuring the cell growth and ion conductivity in medium. The cells were cultured in Murashige and Skoog (MS) medium containing 0.7mg/L 2,4-D, 0.3mg/L kinetin and 30 g/L sucrose at $25^{\circ}C$ in the light (100 rpm). Chemicals were treated to suspension cultures of tobacco PH cells at the time of subculture. The cell growth and ion conductivity in the medium were investigated on 12 days after chemical treatment. The ion conductivity assay gave well correlated results to the cell growth inhibition data. The responses of tobacco PM cells were dependent on the modes of action of chemicals tested. Atrazine, an inhibitor of photosynthetic electron transport (PET), strongly inhibited both the cell membrane and cell growth ($IC_{50}$/, about 1 $\mu$M). Butachlor (an inhibitor of cell division), glufosinate (an inhibitor of amino acid biosynthesis), and fluridone (an inhibitor of carotenoid biosynthesis) showed a dose-dependent inhibition. However, Quinclorac, a herbicide with an auxin activity, did not affect the cell growth and ion leakage. These results suggested that tobacco PM cells is suitable materials for the simple screening of new herbicides such as PET, amino acid biosynthesis, ceil division inhibitors by measuring the cell growth and ion conductivity.

• Biomolecules & Therapeutics
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• v.13 no.4
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• pp.199-206
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• 2005

Cell therapy (CT) is a group of techniques to treat human disorders by transplantation of cells which have been processed and propagated independent of the living body. Blood transfusion and bone marrow transplant have been the primary examples of cell therapy. With introduction of stem cell (SC) technologies, however, CT is perceived as the next generation of biologies to treat human diseases such as cancer, neurological diseases, and heart disease. Despite potential of cell therapy, insufficient guidelines have been implemented concerning safety test and regulation of cell therapy. This review addresses the safety issues to be resolved for the cell therapy, especially SC therapy, to be successfully utilized for clinical practice. Adequate donor cell screening must preceed to ensure safety in cell therapy. In terms of SC culture, controlled, standardized practices and procedures should be established. Further molecular studies should be done on SC development and differentiation to enhance safety level in cell therapy. Finally, animal model must be further installed to evaluate toxicity, new concepts, and proliferative potential of SC including alternative feeder layer of animal cells.

• Archives of Pharmacal Research
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• v.19 no.5
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• pp.342-347
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• 1996

Doxorubicin, one of the clinically most useful anticancer agents, is used alone or in combination with other drugs against a wide variety of tumors, recently. But cancer cells developed resistance to this agent in many ways. This resistance is an important limiting factor of doxorubicin for anticancer drug. We newly established doxorubicin-resistant HCT15/CL02 subline from parental HCT15 human adenocarcinoma colon cancer cells. HCT15/CL02 revealed resistance to doxorubicin about 85-fold of its parental cells, and it also revealed cross-resistance to actinomycin D, etoposide and vinblastine but not to displatin and tamoxifen. And verapamil, a reversal agent of multidrug-resistance (MDR) by P-glycoprotein, elevated the cytotoxicity of doxorubicin against both HCT15 and GCT15/CL02 cells. But the relative resistant rate was not reduced. Verapamil had no effects on the tosicity of cisplatin to the both cell lines. These results indicate that HCT15/CL02 cells have some functionally complex mechanisms for MDR.

• Pediatric Infection and Vaccine
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• v.24 no.3
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• pp.134-140
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• 2017

Purpose: Severe combined immunodeficiency (SCID) is the most serious form of primary immunodeficiency. Infants with SCID are susceptible to life-threatening infections. To establish newborn screening for SCID in Korea, we performed a screening test for T-cell receptor excision circle (TREC) and ${\kappa}$-deleting recombination excision circle (KREC) in neonates and investigated the awareness of SCID among their parents. Methods: Collections of dried blood spots from neonates and parent surveys were performed at the Samsung Medical Center and Cheil General Hospital & Women's Healthcare Center in Korea. The amplification crossing point (Cp) value <37.0 was defined as TREC/KRECpositive based on cutoff values from measuring multiplex real-time polymerase chain reaction. A Cp value >39.0 was defined as negative. Results: For TREC/KREC screening, 141 neonates were enrolled; 63 (44.7%) were male. One hundred forty neonates (99.3%) had positive TREC/KREC results at the time of the initial test; 82.3% and 75.9% were positive and 17.0% and 23.4% were weakly positive for TREC and KREC, respectively. In one neonate (0.7%), the initial TREC/KREC test result was negative. However, repeated tests obtained and confirmed a positive result. For an awareness survey, 168 parents were engaged. Only 2% of parents (3/168) knew that the newborn screening test for SCID had been introduced and performed in other countries. Eighty-four percent of parents (141/168) replied that nationwide newborn SCID screening should be performed in Korean newborns. Conclusions: In this study, newborn SCID screening was performed along with assessment of public awareness of the SCID test in Korea. The study results showed that newborn SCID screening can be readily applied for clinical use at a relatively low cost in Korea.

• Biomedical Science Letters
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• v.15 no.2
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• pp.105-112
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• 2009

The screening of the anti-cancer activity of the chemical library provided 2-thio-4-aminopyrimidine as the initial hit. The confirmation of structure and biological effect of hit was performed by synthesis and biological evaluation. The optimization of hit was performed by derivatization of substituents while keeping the core structure. The evaluation of growth inhibitory activity was carried out using SRB assay against 6 human cancer cell lines and human fibroblast. The growth inhibitory activity of compounds showed substituent dependency and more than 5 compounds showed complete growth inhibition of cancer cell lines at 10 ${\mu}M$ concentration. Chemical library screening followed by synthetic modification provided possibility that 2-thio-4-aminopyrimidine can be used as a new scaffold for the development of anti-cancer agent.

• The KIPS Transactions:PartC
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• v.8C no.4
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• pp.389-396
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• 2001

기존의 라우터 기반의 패킷 스크리닝 방식은 ATM 네트워크 상에서는 패킷 수준의 스크리닝 기능의 적용을 위하여 SAR(Segmentation And Reassembly) 과정을 필요로 하기 때문에 고속의 셀 처리를 수행하는 ATM Switch의 셀 처리 속도를 저하시킨다는 문제점을 안고 있다. 본 논문에서는 셀 스크리닝 방식에 기반한 병렬 처리 구조의 ATM Firewall Switch를 제안한다. 제안된 Enhanced ATM Firewall Switch는 셀 단위로 분할된 패킷의 1, 2번 셀들에 대한 검사만을 통하여 스크리닝 기능을 수행하기 때문에 셀 단위의 스크리닝 수행이 가능하며, 정책 캐쉬의 도입을 통해 셀 스크리닝 수행속도를 향상하였다. 또한 독립적인 User Cells Filter 기능 블록의 설계를 통하여 병렬 처리 구조의 셀 스크리닝 수행이 가능하도록 구성하여 셀 지연 시간을 최소화하였다.

• Korean Journal of Plant Resources
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• v.5 no.1
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• pp.11-23
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• 1992

The experiments tvere carried out to different temperature which affected growth, yield, proximate and antitumor activity in the Codonopsis lanceolata. Growth of aerial part and subterranean partwere best at 2$0^{\circ}C$ and lower 3$0^{\circ}C$. Components of fat, protein and fiber were best at 3$0^{\circ}C$. Wild C.fonceoforo had higher contents of fat, protein, fiber and ash as compared with cultur'ed C.lanceolataArginin was predominant amino acid in both wild and cultivated C.laceolata No significant differ-ence in the mineral contents was found between the wild root and the cultivated at 30'c inbiotronroom. No minerals difference in the contents was found between the cultivated temperature.The content of elements of inorganic metal differs according to the part. C. lanceolata were subjectedto preliminary antitumer screening test with Sarcoma 180 ascites and screening on V-79 cell. Thisexperiments were conducted in accordance with the total packed cell volume method and cytotoxicity method.

• The Journal of the Korean life insurance medical association
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• v.31 no.1
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• pp.34-36
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• 2012

Lung cancer such as small cell lung cancer(SCLC) and non small cell lung cancer(NSCLC) have high mortality rate, so, we insurance doctors have little interest in their risk. But nowadays there's a lot of development in targeted therapy of NSCLC. Screening by CT scanning and early resection strategy also shows better prognosis. It is helpful for underwriters and insurance doctors to review the current development of targeted therapy of NSCLC and estimation of extra-risk of early lung cancer. The preferred treatment option for patients whose tumors contain EGFR-activating mutations are one of the EGFR-directed tyrosine kinase inhibitors, such as gefitinib or erlotinib. In patients with NSCLC whose tumors harboured an ALK rearrangement, there was 61% objective response rate to crizotinib in the phase 1 study. The median survival progression-free survival was 10 months. Mortality analysis of early lung cancer who were detected by CT screening, MR of 105% and EDR of 1‰ were calculated.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.183-183
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• 1998

Telomerase synthesizes telomeric DNA repeats onto chromosome ends de novo. Telomerase activation and telomere shortening in human somatic cells have been implicated in cell tumorigenesis and immortalization. In order to find the potential inhibitors against telomerase activitiy which can be used as potential anticancer agents, we screened about 100 kinds of natural products after partition into n-hexane, ethyl acetate and aqueous layers from methanol extracts. The inhibitory effects of these materials against telomerase enzyme activity were tested in 293T cell culture using telomeric repeat amplification protocol(TRAP). The incorporation of $\^$32/P-dGTP into amplified DNA was measured by adsorption to Whatman DE81 paper instead of using TRAP assay for screening the extracts of natural products. Strong effective compounds were not found in this study but DE81 filter spotting method may be a useful model for the screening. Some of the compounds which showed somewhat inhibitory effects had cytotoxic effects also.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.154.2-154.2
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• 2003

Mammalian cell cycles are tightly regulated by cyclins, cyclin dependent kinase (CDK), Retinoblatoma (Rb) protein, and cellular CDK inhibitors (CDKI). Cyelin dependent kinases (CDK) are key enzymes regulating eukaryotic cell cycle. And also it is recognized that the abnormal increase of CDK activities is one of the common events in human cancer and CDK inhibitors have therapeutic values in cancer treatment. Until now it is known that over 10 different CKDs participate in cell cycle regulation. (omitted)