• 한국동물생명공학회지
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• 제34권2호
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• pp.93-99
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• 2019

Telomeres are known as a specialized region in the end of chromosomes to protect DNA destruction, but their lengths are shortened by repetition of cell division. This telomere shortening can be preserved or be elongated by telomerase and TERT expression. Although a certain condition in the cells may affect to the cellular and molecular characteristics, the effect of differentiation induction to telomere length and telomerase activity in mesenchymal stem cells (MSCs) has been less studied. Therefore, the present study aimed to uncover periodical alterations of telomere length, telomerase activity and TERT expression in the dental pulp-derived MSCs (DP-MSCs) under condition of differentiation inductions into adipocytes and osteoblasts on a weekly basis up to 3 weeks. Shortening of telomere was significantly (p < 0.05) identified from early-middle stages of both differentiations in comparison with undifferentiated DP-MSCs by non-radioactive chemiluminescent assay and qRT-PCR method. Telomere length in undifferentiated DP-MSCs was 10.5 kb, but the late stage of differentiated DP-MSCs which can be regarded as the adult somatic cell exhibited 8.1-8.6 kb. Furthermore, the relative-quantitative telomerase repeat amplification protocol or western blotting presented significant (p < 0.05) decrease of telomerase activity since early stages of differentiations or TERT expression from middle stages of differentiations than undifferentiated state, respectively. Based on these results, it is supposed that shortened telomere length in differentiated DP-MSCs was remained along with prolonged differentiation durations, possibly due to weakened telomerase activity and TERT expression. We expect that the present study contributes on understanding differentiation mechanism of MSCs, and provides standardizing therapeutic strategies in clinical application of MSCs in the animal biotechnology.

• KSBB Journal
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• 제20권5호
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• pp.371-375
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• 2005

암세포가 특정 항암제에 의해 내성을 획득하면 구조가 상이한 타 항암제에도 교차내성을 나타내는 이른바 암세포의 다약제내성(MDR)이 암 화학요법에 있어서 가장 심각한 문제가 되고 있다. 본 연구에서는 점액세균의 대사산물로부터 다약제내성 암세포에 대한 생장억제물질을 탐색하는 과정에서 cellulose 용해성 점액세균인 Sorangium cellulosum Jw1045의 대사산물에서 우수한 활성을 발견하고 그 활성본체로서 polyene-macrolide계 화합물인 chivosazole F를 분리하였다. Chivosazole F는 시험한 인체기원의 암세포에 대해 모두 강한 생장억제작용을 나타내었으며 $(IC_{50}=0.1\~10ng/ml)$, 다약제내성 암세포주인 CL02와 CP70에 대해서도 감수성세포주와 동일한 활성을 나타내었다. 이러한 사실은 chivosazole F가 암세포에 대해 다제내성을 유도하지 않는 우수한 활성물질임을 나타탬과 동시에 다제내성을 극복하는 신규 항암제 선도화합물로서의 유용성을 시사하는 것으로 그 의미가 크다.

• 대한한의학방제학회지
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• 제28권2호
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• pp.137-145
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• 2020

Objectives : Tetragonia tetragonioides is one of the traditional herbal medicines that can be used to protect the stomach and treat cancer. However, its mechanism of overcoming gastrointestinal disorders is unclear. In this study, we investigated antioxidant and anti-inflammatory effects of Tetragonia tetragonioides Water Extract (TTWE) on RAW264.7 cells. Methods : The cell viability by TTWE was measured by using MTT assay. The free radical scavenging ability and cytokine production were analyzed by using ELISA Kit. SPSS version 25 was used for statistical analysis. Results : According to the results of this study, the cell viability measurement of TTWE significantly affected the cell viability. The radical scavenging ability of TTWE showed the highest effect compared to the positive control group when the concentration was 3.1-12.5 ㎍/ml, and significantly inhibited NO production induced by LPS. In addition, the inhibitory effect of TTWE on the production of IL-6 and TNF-α induced by LPS was significant at both TTWE concentrations of 12.5 ㎍/ml [p <0.01 (IL-6), p <0.05 (TNF-α)]. Conclusion : In conclusion, it is suggested that the antioxidant function of Tetragonia tetragonioides Water Extract could be used to prevent and treat inflammatory diseases.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.222.1-222.1
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• 2003

The signal transduction pathway leading to the activation of the p70s6k plays an important role in the progression of cells from G0/G1 to S phase of the cell cycle but remains incompletely characterized. We investigated the role of the Rho family G protein Rac1 in H2O2-mediated p70s6k activation. Transient expression of a dominant negative mutants of the small GTP-binding proteins Rac1 (Rac1N17) and Cdc42(Cdc42N17) showed reduced levels of slower migration on Western blots of one-dimensional SDS-PAGE in p70s6k and ERK1/2 by PDFG stimulation. (omitted)

• 한국광물학회지
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• 제4권1호
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• pp.22-31
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• 1991

세 개의 탈수한 $Ag^+$이온과 $Ca^{2+}$ 이온으로 치환한 제올라이트 $A(Ag_4Ca_4-A,\;Ag_^Ca_3-A,\;Ag_8Ca_2-A)$를 0.1 Torr의 Rb 증기로 처리한 결정구조를 공간군 Pm3m을 써서 단결정 X-선 회절법으로 결정하였다. (단위세포상수 a는 각각 $12.271(1){\AA},\;12.255(1){\AA}$ 및 $12.339(1){\AA}$이다). 이들 구조의 최종 오차인수 R(무게)는 $I>3{\rho}(I)$가 되는 130 회절반사로 0.072, 110 회절반사로 0.050 및 86 회절반사로 0.082이었다. 각각의 구조에서 Rb 종은 세개의 다른 결정학적 위치에 위치하고 있다. 즉 단위세포당 3개의 $Rb^+$이온은 8-링 중심에 위치하고 약 2.5개 내지 3.0개의 $Rb^+$이온은 소다라이트 동공내 3회 회전축상에 위치한다. 또 Ag 종이 두 개의 다른 결정학적 위치에 위치하고 약 0.7∼2.1개의 $Ag^+$이온은 4-링과 마주보는 위치에, 약 2.2∼4.8개의 Ag 원자는 큰 동공 중심 가까이에 위치한다. 이들 구조에서 단위 세포당 Ag 원자이 수는 각각 2.2, 2.4 및 4.8개이었고 이들은 큰 동공 중심에 헥사실버 클라스터를 만든다. $Rb^+$이온은 8-링을 막고 있어서 Ag가 골조 밖으로 이동하는 것을 막고 있고 각각의 헥사실버 클라스터는 13개의 $Rb^+$ 이온과 배위하여 안정화된다. 단위 세포당 약 0.8개의 Rb원자가 과잉으로 존재하여 삼각 대칭형의 $(Rb_3)^{2+}$클라스터가 소다라이트 동공내의 존재한다. 적어도 하나의 큰 동공의 6-링 $Rb^+$ 이온은 소다라이트 동공의 $(Rb_3)^{2+}$클라스터에 접근하므로 이들 클라스터는 $(Rb)_4^{3+}$, $(Rb)_5^{4+}$ 혹은 $(Rb)_6^{5+}$가 형성될 수도 있다.

• Reproductive and Developmental Biology
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• 제30권2호
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• pp.119-124
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• 2006

The present study compared the developmental potential of cloned porcine embryos with mesenchymal stem cells (MSCs), fetal fibroblasts (FFs) and cumulus cells (CCs) by assessing the cleavage and blastocyst rate, total cell number, inner cell mass (ICM) ratio and apoptosis. MSCs were isolated by ficoll gradients from femur of -6 month old female pig, and maintained for primary cultures. FFs from a female fetus at ${\sim}30$ day of gestation were established, and CCs were obtained from cumulus oocyte complexes (COCs) aspirated from $3{\sim}6$ mm follicles in diameter. Donor cells at $3{\sim}4$ passage were employed for nuclear transfer (NT). COCs were matured and fertilized in vitro(IVF) as control. Cleavage rate was significantly (P<0.05) higher in IVF than in NT embryos with MSCs, FFs and CCs ($82.7{\pm}8.9%\;vs\;70.6{\pm}5.4,\;68.7{\pm}5.1\;and\;63.4{\pm}5.6%$, respectively). However, blastocyst rates in IVF and NT embryos derived from MSCs ($24.5{\pm}2.8\;and\;20.4{\pm}8.3%$) did not differ, but were significantly (P<0.05) higher than NT derived from FFs and CCs ($10.6{\pm}2.7\;and\;9.8{\pm}2.1%$). Total cell number and the ratio of ICM to total cells among blastocysts cloned from MSCs ($35.4{\pm}5.2\;and\;0.40{\pm}0.09%$, respectively) were significantly (P<0.05) higher than those from FFs and CCs ($24.9{\pm}6.2%\;vs\;0.19{\pm}0.16,\;23.6{\pm}5.5\;and\;0.17{\pm}0.16%$, respectively). Proportions of TUNEL positive cells in NT embryos from FFs and CCs ($6.9{\pm}1.5\;and\;7.4{\pm}1.7%$, respectively) were significantly (P<0.05) higher than in MSCs ($4.8{\pm}1.4%$) and IVF ($2.3{\pm}0.9%$). The results demonstrate that MSCs have a greater potential as donor cells than FFs and CCs in achieving enhanced production of cloned porcine embryos.

• 대한수의학회지
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• 제35권3호
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• pp.635-641
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• 1995

The purpose of this study was to investigate the effects of developmental stage and equilibration time on survival of rabbit embryos following freezing by vitrification. Adult New Zealand White female rabbits were superovulated with PMSG and hCG. The 8-cell stage embryos were collected from 40 to 45 hours after hCG injection by flushing oviducts with Dulbecco's phosphated buffered saline and in vitro cultured in TCM-199 containing 10% fetal calf serum(FCS). Each embryos developed in vitro to 16-cell, compact morula and blastocyst was cryopreserved and cultured following thawing to examine their developmental potential to expanded blastocyst stage in vitro. The frozen-thawed-cultured embryos were stained with Hoechst 33342, and their nuclei were counted using a fluorescence microscope. On the toxicity test of EFS solution as cryopreservation, the survival rates of 8-cell stage embryos was decreased in reverse to increasing of exposure time over 5 minutes. The post-thaw survival rates of embryos on equilibration times was significantly(P<0.05) higher for 2 min. than for 5 or 10 minutes. From morula to blastocyst of rabbit embryos was more suitable than 8-cell stage for cryopreservation by vitrification. The higher post-thaw survival rate of embryos can be achieved by keeping the cryoprotectant at $4^{\circ}C$ than at $20^{\circ}C$. The mean number of nuclei per embryo following freezing by vitrification and in vitro culture to expanded blastocyst at compacted morula and blastcyst was not significantly differ from fresh blastocyst.

• 동의생리병리학회지
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• 제18권4호
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• pp.1021-1027
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• 2004

Panax ginseng has been used as a typical tonic medicine in Asian countries, such as Korea, China, and Japan. It has been reported that ginsenoside Rg1 in Panax ginseng increases the proportion of T helper cells in the whole T cells and promotes IL-2 gene expression in murine splenocytes. These studies imply that ginsenoside Rg1 increases the immune activity of CD4+ T cell, however the exact mechanism of ginsenoside Rg1 on helper T cell remains to be verified. The present study tried to elucidate the direct effect of Rg1 on helper T cell s activities and its Th1/Th2 lineage development. The results demonstrated that ginsenoside Rg1 had not mitogenic effects on the unstimulated CD4+ T cell, but augmented CD4+ T cell proliferation upon activating with anti-CD3/anti-CD28 antibodies in a dose dependent manner. Rg1 also enhanced the expression of cell surface protein CD69 on CD4+ T cell. In Th0 condition, ginsenoside Rg1 increases the expression of IL-2 mRNA, and enhances the expression of IL-4 mRNA on CD4+ T cells, suggesting Rg1 prefer to induce Th2 lineage development. In addition, ginsenoside Rg1 increases IL-4 secreting CD4+ T cell under Th2 skewed condition, while decreases IFN-γ secreting cell in Th1 polarizing condition. Thus, Rg1 enhances Th2 lineage development from naive CD4+ T cell both by increasing Th2 specific cytokine secretion and by repressing Th1 specific cytokine production. Therefore, these results suggest that ginsenoside Rg1 might be desirable agent for enhancing CD4+ T cell's activity, as well as the correction of Th1 dominant pathological disorders.

• Journal of Microbiology and Biotechnology
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• 제18권11호
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• pp.1785-1788
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• 2008

Phenylpyropenes A, B, and C, isolated from Penicillium griseofulvum F1959, inhibited DGAT in rat liver microsomes with $IC_{50}$ values of $78.7{\pm}1.6$, $21.7{\pm}0.2$, and $11.04{\pm}0.2{\mu}M$, respectively. In addition, a kinetic analysis using a Lineweaver-Burk plot revealed that phenylpyropene C was a noncompetitive inhibitor of DGAT. The apparent Michaelis constant ($K_m$) value and inhibition constant ($K_i$) value were calculated to be $8{\mu}M$ and $10.48{\mu}M$, respectively. Moreover, phenylpyropene C inhibited triglyceride formation in HepG2 cells.

• 한국양식학회지
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• 제10권1호
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• pp.25-32
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• 1997

코끼리조개의 인공종묘생산 기술개발의 일환으로 성숙된 모패를 절개법에 의하여 인공수정시켜 난 발생 및 유생의 발달과정을 관찰한 결과를 요약하면 다음과 같다. 코끼리조개의 난은 분리침성란으로 나타났으며, 방란직후 알의 모양은 타원형이나 수정이 되면 직경 $70\mu$m의 구형으로 된다. 수정난의 발생은$ 11^{citc}C$에서 4시간 후 4세포기로 되고, 2일이 지나면 담륜자 유생(trochophore larvae), 수정 후 3일째에는 D상 유생, 23일째에는 각정기, 36일째에는 성숙유생으로 되었다. 수온(w)에 따른 각 단계별 소요시간(t)의 관계를 보면, 8세포 : 1/t=0.0209 w-0.1167 (r=0.9967) 포배기 : 1/t=0.0055 w-0.0192 (r=0.9825) 담륜자기 : 1/t=0.0034 w-0.0155 (r=0.9907) D상 유생기 : 1/t=0.0014 w-0.0023 (r=0.9843) 상기 식에서 산출된 코끼리조개의 생물학적 기초수온은 3.82$^{\circ}C$였다.