• Journal of Microbiology and Biotechnology
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• 제18권3호
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• pp.523-531
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• 2008

Radiotherapy is currently applied in the treatment of human cancers. We studied whether genistein would enhance the radiosensitivity and explored its precise molecular mechanism in cervical cancer cells. After co-treatment with genistein and irradiation, the viability, cell cycle analysis, and apoptosis signaling cascades were elucidated in CaSki cells. The viability was decreased by co-treatment with genistein and irradiation compared with irradiation treatment alone. Treatment with only ${\gamma}$-irradiation led to cell cycle arrest at the $G_1$ phase. On the other hand, co-treatment with genistein and ${\gamma}$-irradiation caused a decrease in the $G_1$ phase and a concomitant increase up to 56% in the number of $G_2$ phase. In addition, co-treatment increased the expression of p53 and p21, and Cdc2-tyr-15-p, supporting the occurrence of $G_2/M$ arrest. In general, apoptosis signaling cascades were activated by the following events: release of cytochrome c, upregulation of Bax, down regulation of Bcl-2, and activation of caspase-3 and -8 in the treatment of genistein and irradiation. Apparently, co-treatment downregulated the transcripts of E6*I, E6*II, and E7. Genistein also stimulated irradiation-induced intracellular reactive oxygene, species (ROS) production, and co-treatment-induced apoptosis was inhibited by the antioxidant N-acetylcysteine, suggesting that apoptosis has occurred through the increase in ROS by genistein and ${\gamma}$-irradiation in cervical cancer cells. Gamma-irradiation increased cyclooxygenase-1 (COX-2) expression, whereas the combination with genistein and ${\gamma}$-irradiation almost completely prevented irradiation-induced COX-2 expression and $PGE_2$ production. Co-treatment with genistein and ${\gamma}$-irradiation inhibited proliferation through $G_2/M$ arrest and induced apoptosis via ROS modulation in the CaSki cancer cells.

• 생명과학회지
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• 제19권5호
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• pp.671-675
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• 2009

Prostate cancer has been a critical health problem due to an increase of prostate cancer-related deaths worldwide. Also, a frequent treatment option for prostate cancer is androgen ablation, but this treatment has a limited scope, especially for hormone-refractory cancer. There is an urgent need for the identification of alternative therapeutic strategies for prostate cancer. Previously, over one hundred species of dried-plant methanol extracts were tested for inhibitory effects on proliferation. One of them, Piper longum Linn. was selected based on its potent anti-proliferation effect. The dried root of P. longum Linn. was extracted with 100% methanol for 2-3 days and its extract was fractionated using chloroform. The chloroform layer was then subjected to column chromatography on silica gel, reverse phase-18 (RP-18) and Sephadex LH-20, in turn. Finally, the pure compound was obtained and identified as pipernonaline by NMR spectroscopic and physico-chemical analysis. In this study, anti-proliferation and cell cycle arrest effects of pipernonaline on human prostate cancer PC-3 cells were investigated using the MTT and PI staining, respectively. Our findings suggest that pipernonaline represents a dose-dependent growth inhibition pattern on PC-3 cells and, moreover, its growth inhibition is associated with sub-G1 and G0/G1 cell cycle accumulation in PC-3 cells. Also, these results provide an anticancer candidate for human prostate cancer.

• 한국식품과학회지
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• 제34권2호
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• pp.274-282
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• 2002

물레나물 에탄올 추출물과 헥산 분획물은 L. monocytogenes 5균주에 대해 25 ppm에서 72시간까지 완전 균증식 억제 효과가 있었다. 물레나무 헥산 분획물의 항균활성 물질을 분리, 정제하여 얻은 H2-5-2 소획분의 경우 실험 MIC가 10 ppm으로 그 항균력을 생균수로 나타내었을 때 초기 접종 균수보다 0.5 log cycle정도 감소하여 그 살균효과를 알 수 있었다. 물레나물 헥산 분획물의 항균 스펙트럼을 살펴보면 B. cereus나 S. aureus에 대해서는 실험 최저 농도인 25 ppm에서도 72시간까지 완전 증식억제 효과를 나타내었으며, V. parahaemolyticus에 대해서는 50 ppm 첨가시 72시간 동안 균증식이 억제되었다. 물레나물의 항균활성 물질은 불포화도가 높은 sterol로 추정되었다. 쇠고기와 명태육 마쇄물에 물레나물 헥산 분획물을 첨가하여 $32^{\circ}C$ 와 $5^{\circ}C$에서 식품 적용 실험을 실시한 결과 $32^{\circ}C$ 저장온도에서는 쇠고기, 명태육에 첨가한 물레나물 헥산 분획물의 항균효과가 나타나지 않았고, $5^{\circ}C$ 저장온도에서는 명태육에 첨가된 물레나물 헥산 분획물은 항균효과가 있었다. 그러나 물레나물 헥산 분획물의 항균효과는 배양액 상태보다 감소하였다.

• Journal of Korean Medical Science
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• 제33권47호
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• pp.303.1-303.10
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• 2018

Background: Cell division cycle 6 (CDC6) is an essential regulator of DNA replication and plays important roles in the activation and maintenance of the checkpoint mechanisms in the cell cycle. CDC6 has been associated with oncogenic activities in human cancers; however, the clinical significance of CDC6 in prostate cancer (PCa) remains unclear. Therefore, we investigated whether the CDC6 mRNA expression level is a diagnostic and prognostic marker in PCa. Methods: The study subjects included 121 PCa patients and 66 age-matched benign prostatic hyperplasia (BPH) patients. CDC6 expression was evaluated using real-time polymerase chain reaction and immunohistochemical (IH) staining, and then compared according to the clinicopathological characteristics of PCa. Results: CDC6 mRNA expression was significantly higher in PCa tissues than in BPH control tissues (P = 0.005). In addition, CDC6 expression was significantly higher in patients with elevated prostate-specific antigen (PSA) levels (> 20 ng/mL), a high Gleason score, and advanced stage than in those with low PSA levels, a low Gleason score, and earlier stage, respectively. Multivariate logistic regression analysis showed that high expression of CDC6 was significantly associated with advanced stage (${\geq}T3b$) (odds ratio [OR], 3.005; confidence interval [CI], 1.212-7.450; P = 0.018) and metastasis (OR, 4.192; CI, 1.079-16.286; P = 0.038). Intense IH staining for CDC6 was significantly associated with a high Gleason score and advanced tumor stage including lymph node metastasis stage (linear-by-linear association, P = 0.044 and P = 0.003, respectively). Conclusion: CDC6 expression is associated with aggressive clinicopathological characteristics in PCa. CDC6 may be a potential diagnostic and prognostic marker in PCa patients.

• 식물조직배양학회지
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• 제27권6호
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• pp.423-428
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• 2000

In 1997 when cloned sheep Dolly and soon after Polly were born, it had become head-line news because in the former the nucleus that gave rise to the lamb came from cells of six-year-old adult sheep and in the latter case a foreign gene was inserted into the donor nucleus to make the cloned sheep produce human protein, factor IX, in e milk. In the last few years, once the realm of science fiction, cloned mammals especially in livestock have become almost commonplace. What the press accounts often fail to convey, however, is that behind every success lie hundreds of failures. Many of the nuclear-transferred egg cells fail to undergo normal cell divisions. Even when an embryo does successfully implant in the womb, pregnancy often ends in miscarriage. A significant fraction of the animals that are born die shortly after birth and some of those that survived have serious developmental abnormalities. Efficiency remains at less than one % out of some hundred attempts to clone an animal. These facts show that something is fundamentally wrong and enormous hurdles must be overcome before cloning becomes practical. Cloning researchers now tent to put aside their effort to create live animals in order to probe the fundamental questions on cell biology including stem cells, the questions of whether the hereditary material in the nucleus of each cell remains intact throughout development, and how transferred nucleus is reprogrammed exactly like the zygotic nucleus. Stem cells are defined as those cells which can divide to produce a daughter cell like themselves (self-renewal) as well as a daughter cell that will give rise to specific differentiated cells (cell-differentiation). Multicellular organisms are formed from a single totipotent stem cell commonly called fertilized egg or zygote. As this cell and its progeny undergo cell divisions the potency of the stem cells in each tissue and organ become gradually restricted in the order of totipotent, pluripotent, and multipotent. The differentiation potential of multipotent stem cells in each tissue has been thought to be limited to cell lineages present in the organ from which they were derived. Recent studies, however, revealed that multipotent stem cells derived from adult tissues have much wider differentiation potential than was previously thought. These cells can differentiate into developmentally unrelated cell types, such as nerve stem cell into blood cells or muscle stem cell into brain cells. Neural stem cells isolated from the adult forebrain were recently shown to be capable of repopulating the hematopoietic system and produce blood cells in irradiated condition. In plants although the term$\boxDr$ stem cell$\boxUl$is not used, some cells in the second layer of tunica at the apical meristem of shoot, some nucellar cells surrounding the embryo sac, and initial cells of adventive buds are considered to be equivalent to the totipotent stem cells of mammals. The telomere ends of linear eukaryotic chromosomes cannot be replicated because the RNA primer at the end of a completed lagging strand cannot be replaced with DNA, causing 5' end gap. A chromosome would be shortened by the length of RNA primer with every cycle of DNA replication and cell division. Essential genes located near the ends of chromosomes would inevitably be deleted by end-shortening, thereby killing the descendants of the original cells. Telomeric DNA has an unusual sequence consisting of up to 1,000 or more tandem repeat of a simple sequence. For example, chromosome of mammal including human has the repeating telomeric sequence of TTAGGG and that of higher plant is TTTAGGG. This non-genic tandem repeat prevents the death of cell despite the continued shortening of chromosome length. In contrast with the somatic cells germ line cells have the mechanism to fill-up the 5' end gap of telomere, thus maintaining the original length of chromosome. Cem line cells exhibit active enzyme telomerase which functions to maintain the stable length of telomere. Some of the cloned animals are reported prematurely getting old. It has to be ascertained whether the multipotent stem cells in the tissues of adult mammals have the original telomeres or shortened telomeres.

• 생물환경조절학회지
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• 제26권3호
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• pp.167-174
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• 2017

본 연구는 우리나라의 대표적인 조림수종인 소나무를 대상으로 조림지 식재 후 활착률을 높이기 위해 상대적으로 생육이 좋은 용기묘로 생산하고자 할 때, 관수처리 수준에 따른 생장 반응 특성을 조사하고 이를 통하여 적정 관수 수준을 구명하고자 실시되었다. 104구 용기에서 생육된 소나무 용기묘는 대조구(무관수)를 포함하여 파종 후 15주부터 8주 동안 각각 1, 2, 3, 5, 7, 10, 15일 간격으로 관수되었다. 관수처리에 따른 소나무 용기묘의 간장과 근원경 생장, 건물생산량을 조사한 결과 가장 좋은 생장 반응은 관수처리 1일 간격에서 가장 높게 나타났다. 관수주기가 짧아질수록 소나무 용기묘의 생장이 좋아졌지만, 전체뿌리길이는 2일이나 1일 관수주기보다 3일에서 더 높게 나타났다. 묘목품질지수의 경우 1일 간격에서 가장 높고 관수주기가 길어질수록 낮아지는 경향을 보였다. 본 연구결과를 종합하면 1~2일 간격의 관수가 소나무 용기묘의 생육에 있어 적합한 것으로 판단된다.

• Parasites, Hosts and Diseases
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• 제51권6호
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• pp.711-717
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• 2013

Opisthorchis viverrini (O. viverrini) is a well-known causative agent of cholangiocarcinoma (CCA) in humans. CCA is very resistant to chemotherapy and is frequently fatal. To understand the pathogenesis of CCA in humans, a rodent model was developed. However, the development of CCA in rodents is time-consuming and the xenograft-transplantation model of human CCA in immunodeficient mice is costly. Therefore, the establishment of an in vivo screening model for O. viverrini-associated CCA treatment was of interest. We developed a hamster CCA cell line, Ham-1, derived from the CCA tissue of O. viverrini-infected and N-nitrosodimethylamine-treated Syrian golden hamsters. Ham-1 has been maintained in Dulbecco's Modified Essential Medium supplemented with 10% fetal bovine serum for more than 30 subcultures. These cells are mostly diploid (2n=44) with some being polyploid. Tumorigenic properties of Ham-1 were demonstrated by allograft transplantation in hamsters. The transplanted tissues were highly proliferative and exhibited a glandular-like structure retaining a bile duct marker, cytokeratin 19. The usefulness of this for in vivo model was demonstrated by berberine treatment, a traditional medicine that is active against various cancers. Growth inhibitory effects of berberine, mainly by an induction of G1 cell cycle arrest, were observed in vitro and in vivo. In summary, we developed the allo-transplantable hamster CCA cell line, which can be used for chemotherapeutic drug testing in vitro and in vivo.

• 생명과학회지
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• 제29권5호
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• pp.514-523
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• 2019

인삼(Panax ginseng C. A. Meyer)의 사포닌 진세노사이드 Rb1이 처리된 인간 피부각질세포 HaCaT에서 microarray 분석 및 발현이 증가된 세포사멸 반응에 대한 작용기전을 연구하였다. HaCaT 세포에 진세노사이드 Rb1의 처리로 세포사멸, 유사분열 세포주기의 G2/M 전이, 세포분열, 핵분열, 그리고 단백질 수송 등의 작용기전에 관여하는 유전자들이 2 배 이상 발현이 증가된 것으로 나타났으며, DNA 수선, 감수 핵분열, 그리고 세포외기질 체계 등의 작용기전에 관여하는 유전자들은 2 배 이상 발현이 감소된 것으로 나타났다. 특히 세포사멸 신호전달은 FAS와 PLA2G4A를 경유하는 것으로 나타났으며, 이들 유전자의 상위 조절자로 STAT3가 예측되었다. 세포사멸 반응 경유 유전자 FAS와 PLA2G4A의 활성을 qPCR로 확인한 결과, FAS 유전자는 $10{\mu}g/ml$의 진세노사이드 Rb1를 24시간 동안 처리하였을 경우 약 2 배의 발현 증가와, PLA2G4A 유전자는 6시간 처리부터 약 2 배로 증가되어 24시간 동안 처리시 2 배 이상의 유전자 발현이 증가되었다. 한편 STAT3-siRNA를 이용한 knock-down 실험에서 FAS의 발현 감소와 PLA2G4A의 발현 증가로 상위 조절자 STAT3로부터 FAS 만을 경유하는 것을 알 수 있었다. 이상의 결과 진세노사이드 Rb1의 처리에 의해 상위 조절자인 STAT3는 FAS를 경유하여 세포사멸을 유도하는 것임을 알 수 있다.

• 한국응용과학기술학회지
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• 제34권2호
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• pp.280-288
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• 2017

에너지 저장 매체는 소형화, 고효율화 및 그린에너지 정책에 부합하면서 연구개발이 진행되고 있으며 유연성과 신축성을 갖는 디스플레이나 웨어러블 전자기기의 발전에 상응하는 에너지 저장 매체의 개발이 시급한 상황으로 이를 실현 할 수 있는 물질가운데, 탄소나노 재료중의 하나인 그래핀과 그래핀 하이브리드와 같은 뛰어난 전기화학적 특성을 지니고 있는 나노 재료가 각광을 받고 있다. 또한 슈퍼커패시터와 배터리 및 연료전지 등과 같은 에너지 저장 소자에 응용하기 위한 연구가 활발하게 진행 중에 있으며, 여러 가지 에너지 저장 매체 중 단시간에 고출력을 구현하고 장시간 신뢰성을 갖추며, 빠른 충 방전 순환특성을 가지는 슈퍼커패시터는 차세대 에너지원으로 많은 관심을 받고 있다. 본 연구에서는 플렉시블한 특성을 갖는 그래핀과 전도성 고분자 하이브리드 전극을 기반으로 하는 슈퍼커패시터를 개발하고자 하였으며 환원된 그래핀 옥사이드/폴리피롤 복합재료를 이용하여, 전기화학적 특성을 최대화 하였다. 그 결과 굽힘 시험 전 전극의 초기 용량값은 $198.5F\;g^{-1}$ 이었으며, 500번의 굽힘 시험 후 $128.3F\;g^{-1}$로 감소하는 것을 확인하였으나, 전극의 초기 전기 용량 값의 65 %의 성능을 유지하였다.

• Laboratory Medicine Online
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• 제6권1호
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• pp.25-30
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• 2016

배경: Thymidine kinase 1 (TK1)은 세포 주기의 중요한 조절 효소로 암세포의 증식 시에 증가하는 것으로 알려져 있으며, 현재까지 혈액종양과 다양한 고형암에서 진단 또는 치료 후 모니터링과 예후 예측에 중요한 표지자로 보고되고 있다. 본 연구에서는 한국인에서 혈청 TK1 정량분석을 통하여 건강인의 혈청 TK1 참고치를 설정하고자 하였으며 B세포림프종 환자를 대상으로 임상적 악성도 표지자로서 혈청 TK1 검사의 유용성을 평가하고자 하였다. 방법: 72명의 B세포림프종 환자와 143명의 건강대조군의 혈청검체에서 화학발광면역측정법으로 혈청 TK1 농도를 측정하였다. 건강대조군에서 혈청 TK1의 참고치를 설정하였고, 환자군과 건강대조군에서 측정된 혈청 TK1 결과를 이용해 ROC 분석을 통한 기준치를 구하여 상대적으로 높은 혈청 TK1 정량값과 B세포림프종의 임상 지표들과의 상관성을 비교하였다. 결과: 전체 건강대조군의 혈청 TK1의 95 percentile에 따른 참고범위는 5.4-21.8 U/L였다. B세포림프종 환자군과 건강대조군의 혈청 TK1 수치 비교에서 평균${\pm}$표준편차는 각각 $40.6{\pm}68.5U/L$와 $11.8{\pm}4.4U/L$로 나타났으며 두 그룹 간에 유의한 차이를 보였다(P<0.001). ROC 분석 후, 혈청 TK1 수치 15.2 U/L를 이용하였을 때 민감도 59.7%, 특이도 83.2%, AUC 0.73을 보여 B세포림프종 환자를 선별할 수 있는 기준치로 설정하였다. 상대적으로 높은 혈청 TK1 수치(${\geq}15.2U/L$)는 병기, 골수침범, IPI 점수, LD 수치, 낮은 Hb (<12 g/dL), 림프구 수와 상관성이 있는 것으로 나타났다. 결론: B세포림프종 환자에서 측정되는 혈청 TK1 수치는 B세포림프종의 임상적 악성도 표지자로서 유용하게 사용될 수 있을 것이다.