• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.1007-1021
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• 2018

Cancer represents one of the most significant threats to human health on a global scale. Hence, the development of effective cancer prevention strategies, as well as the discovery of novel therapeutic agents against cancer, is urgently required. In light of this challenge, this research aimed to evaluate the effects of several potent bioactive peptides and proteins contained in crocodile white blood cell extract (cWBC) against LU-1, LNCaP, PC-3, MCF-7, and CaCo-2 cancer cell lines. The results demonstrate that 25, 50, 100, and $200{\mu}g/ml$ cWBC exhibits a strong cytotoxic effect against all investigated cell lines ($IC_{50}$ $70.34-101.0{\mu}g/ml$), while showing no signs of cytotoxicity towards noncancerous Vero and HaCaT cells. Specifically, cWBC treatment caused a significant reduction in the cancerous cells' colony forming ability. A remarkable suppression of cancerous cell migration was observed after treatment with cWBC, indicating potent antimetastatic properties. The mechanism involved in the cancer cell cytotoxicity of cWBC may be related to apoptosis induction, as evidenced by typical apoptotic morphology features. Moreover, certain cWBC concentrations induced significant overproduction of ROS and significantly inhibited the $S-G_2/M$ transition in the cancer cell. The molecular mechanisms of cWBC in apoptosis induction were to decrease Bcl-2 and XIAP expression levels and increase the expression levels of caspase-3, caspase-8, and p53. These led to a decrease in the expression level of the cell cycle-associated gene cyclin-B1 and the arrest of cell population growth. Consequently, these findings demonstrate the prospect of the use of cWBC for cancer therapy.

• IMMUNE NETWORK
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• v.2 no.1
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• pp.60-64
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• 2002

Background: Chemotherapy with 5-fluorouracil (5-FU) has been one of the mainstay in breast cancer treatment. The effects of high dose 5-FU on cell cycle regulation were studied in breast caner cells. Methods: A breast cancer cell line MCF-7 was used. Protein expressions of G1/S cyclins, $p21^{Waf1/Cip1}$, cdk2, E2F1 and retinoblastoma were tested by western blot analysis. Immunoprecipitation and immune complex kinase assay were done for the assessment of E2F1/RB interacton and the activity of cdk2 respectively. Results: $p21^{Waf1/Cip1}$ expression was barely detectable in control cells. With addition of 5-FU level of $p21^{Waf1/Cip1}$ were induced and cyclin D3 level was decreased as cell growth decreases. In accordance with increased expression of $p21^{Waf1/Cip1}$, cyclin E-associated cdk2 kinase activity was reduced. Retinoblastoma protein (RB) became dephosphorylated and E2F-1 binding activity with RB was increased. Conclusion: In this situation of high concentration of 5-FU breast cancer cells tend to be G1/S cell cycle arrested. Overexpression of $p21^{Waf1/Cip1}$ and dephosphorylation of RB may mediate the effectss of 5-FU by inhibiting E2F-1 activity, which contributes to G1/S cell cycle arrest. These results could be an indicating landmark for further study of high dose chemotherapy with 5-FU.

• Journal of the korean academy of Pediatric Dentistry
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• v.39 no.2
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• pp.199-205
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• 2012

Although the stainless steel crowns have been recognized as the most effective and durable form of restoration for primary molars, they have been regarded by many dentists as having definite demerits such as invasive nature of procedural complexity and behavioral aspects of children. As an alternative to conventional technique of stainless steel crown restoration, the Hall technique was first introduced in 1988, which is characterized by just pushing the pre-contoured, cement filled crown form onto the abutment molar with no local anesthesia, no caries removal, no tooth preparation. According to several reports, this can slow, arrest, or even reverse the progress of caries. In addition, its atraumatic feature gives less discomfort and stress to children than conventional one, which is thought excellent especially in younger children. Also, It has been reported to be effective and acceptable to dentist, child patients and their parents. In this case study, three children with age of 4 years 5 months, 4 years 10 months, 6 years 4 months were treated with stainless steel crowns using Hall technique on first primary molar respectively. The teeth were free from pulpal, periapical pathology. After follow up of about 3 to 6 months period, the results showed clinically successful outcomes without any marked complication in pulp, tooth or soft tissue till now. But, it should be kept in mind that this technique is not proper to every child, every carious molar, or every dentist. Thorough distinction of indicated cases and continuous follow-up check is highly required. Conclusively, Hall technique might be an effective and realistic minimally invasive alternative for the carious primary molars especially in younger or disabled children, despite potential doubts on its efficacy and some definite limitations.

• Animal cells and systems
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• v.14 no.4
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• pp.261-266
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• 2010

PC12 cells were differentiated into the cells of chromaffin phenotype by butyrate treatment. Cells were aggregated and formed tight cell adhesion. To investigate the molecular change in this differentiation, we examined expression levels of cell adhesion proteins and extracellular proteins during butyrate induced-differentiation of PC12 cells. Integrin ${\beta}1$, integrin ${\alpha}7$, E cadherin, VCAM, collagen-I, fibronectin, desmoglein and connexin were increased during differentiation. The levels of clusterin and secreted clusterin were also increased. These increased levels of cell adhesion proteins and extracellular proteins appear to induce cell aggregation and tight cell adhesion. The levels of p21, p27 and p16 were increased probably because of differentiation-related growth arrest during differentiation. Prolonged incubation of butyrate up to 1 day was required for differentiation. Signal transduction pathways for this differentiatiom could not be identified since various inhibitors had no effect. The results showed that butyrateinduced differentiation of PC12 cells to chromaffin cells involves tight cell adhesion and induction of extracellular proteins and cell adhesion proteins.

• The Journal of the Convergence on Culture Technology
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• v.4 no.1
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• pp.193-200
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• 2018

This study is an experiential case study of cybercrime fraud that combines pharming and voice phishing in April 2017. Research on victims who have actually suffered in the study of crime or disaster is a very useful field in establishing crime prevention measures. This study is significant in that Korea is relatively poor in this kind of research. I got cyber fraud as a consequence of my loss of reasonable judgment due to mental confusion when a companion dog who was raised for 8 years was in a very dangerous situation with cystitis. Fortunately, I received all the damages in a quick report, but the period was eight months. It took too much time to get back all the damages, so I had to suffer another pain. Based on my experience, I suggest damage prevention measures. First, when a certain condition and a certain amount are transferred, the transaction is automatically stopped or a more strict confirmation procedure is added. Secondly, trafficking means to arrest the perpetrator without any harm to the victim is sought. Third, the victims of crime should be promptly reimbursed for damages or a system for lending their living funds to zero or lower interest rate.

• Korean journal of communication and information
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• v.25
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• pp.103-133
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• 2004

Korean citizens enjoy not only the freedom of communication but also the secrecy of electronic communication. Article 18 of the Constitution of the Republic of Korea prescribes that the secrecy of correspondence should not be infringed. Namely, all citizens enjoy guaranteed privacy of correspondence. But many people have been experiencing the infringement of those rights. The purpose of this paper is to evaluate whether Paragraph 2, Article 13 of the Act on Protection of the Secrecy of Correspondence infringes on the constitutional rights of privacy of electronic communication. The results of this study indicate that the law violates the Constitution. Paragraph 3, Article 12 (Personal Liberty, Personal Integrity) of the constitution stipulates that "Warrants issued by a judge through due process (upon the request of a prosecutor) have to be presented in case of arrest, detention, seizure, or search." However, prosecutors, the police, and National Intelligence Service have made numerous inquiries calling for the journalists' telephone records without warrants issued by a judge. So, this study suggests that the paragraph should be amended to be compatible with the Constitution. Meanwhile, journalists should make a more concerted effort to protect their news sources in exercising constitutionally protected freedom of the press.

• Korean Journal of Agricultural Science
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• v.23 no.2
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• pp.212-218
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• 1996

This study was conducted to investigate the effects of coculture for the development rate to morula/blastocyst stages of early porcine embryos, derived from oocytes matured and fertilized In vitro, with porcine cumulus cell monolayers(PCM) in the two different media, respectively. The rates of embryos developed to 2-, 4-, 8~16-cell and morula/blastocyst stage were 48.7, 40.5, 34.8 and 17.0% in Ham's F-10 with PCM, and 48.3, 35.6, 22.1, and 13.4% in TCM-HEPES with PCM, respectively. The above development rates to morula/blastocyst stages were significantly higher than those of the embryos cultured in the Ham's F-10 and TCM-HEPES without PCM(P<0.05). The in vitro development rates to the morula/blastocyst stage of I-cell embryos cultured in Ham's F-10 and TCM-HEPES without PCM were 0.0~1.0%. Especially, most of embryos were observed to arrest the development beyond 4-cell stages. As shown in the above results, the coculture of in vitro fertilized porcine embryos with PCM in the two different media enhanced the development of fertilized eggs to morula/blastocyst stages in vitro. However, we didn't find out any difference for the in vitro development to morula/blastocyst stages between Ham's F-10 and TCM-HEPES media.

• Clinical and Experimental Reproductive Medicine
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• v.31 no.3
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• pp.155-168
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• 2004

Objective: Melatonin, which is secreted by pineal gland play an important role in the regulation of ovarian function via seasonal rhythm and sleep in most mammals. It also has a role in the protection of cells by removing toxic oxygen free radicals brought about by metabolism. In the present study, effects of melatonin on the mouse oocyte maturation were examined using two different culture conditions provided with 5% or 21% oxygen concentration. Material and Method: Immature mouse oocytes were obtained from the ovarian follicles of $3{\sim}4$ weeks old ICR strain mice intraperitoneally injected with 5 I.U. PMSG 44 hour before. Under stereomicroscope, morphologically healthy oocytes with distinct germinal vesicle (GV) were liberated from the graafian follicles and collected using mouth-controlled micropipette. They were then cultured for 17 hour at $37^{circ}C$, 5% $CO_2$ and 21% $O_2$ (95% air) or 5% $CO_2$, 5% $O_2$ and 90% $N_2$. New modified Hank's balanced salt solution (New MHBS) was used as a culture medium throughout the experiments. Effects of melatonin were examined at a concentration of $0.0001{\mu}M$, $0.01{\mu}M$ or $1.0{\mu}M$. For the prevention of spontaneous maturation of immature oocytes during culture, dibutyryl cyclic AMP (dbcAMP) and/or hypoxanthine were included in the medium. Results: Under 21% oxygen condition, oocytes cultured in the presence of $0.01{\mu}M$ melatonin showed a significantly higher maturation rates, in terms of germinal vesicle breakdown (95.0% vs 89.0%) and polar body formation (88.1% vs 75.4%), compared to those cultured with $0.0001{\mu}M$ or $1.0{\mu}M$ melatonin. However, no difference was observed in oocytes cultured under 5% oxygen whether they were treated with melatonin or not. In the presence of $0.01{\mu}M$ melatonin, oocytes either cultured under 21% or 5% oxygen exhibited no difference in the polar body formation (85.6% vs 86.7%). However, in the absence of melatonin, oocytes cultured under 21% oxygen exhibited lower polar body formation (74.7%). When oocytes were cultured in the presence of dbcAMP alone or with varying concentrations of melatonin, those treated with both compounds always showed better maturation, i.e., germinal vesicle breakdown and polar body formation, compared to those cultured with dbcAMP alone. At the same concentration of melatonin, however, oocytes exposed to 21% oxygen showed poor maturation than those to 5% oxygen. Similar results were obtained from the experiments using hypoxanthine instead of dbcAMP. Conclusion: Based upon these results, it is suggested that melatonin could enhance the meiotic maturation of mouse oocytes under 21% oxygen concentration, and release oocytes from the meiotic arrest by dbcAMP or hypoxanthine regardless of the concentration of oxygen, probably via the removal of oxygen free radicals.

• Journal of Ginseng Research
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• v.44 no.2
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• pp.341-349
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• 2020

Background: The replicative senescence of human dermal fibroblasts (HDFs) is accompanied by growth arrest. In our previous study, the treatment of senescent HDFs with Rg3(S) lowered the intrinsic reactive oxygen species (ROS) levels and reversed cellular senescence by inducing peroxiredoxin-3, an antioxidant enzyme. However, the signaling pathways involved in Rg3(S)-induced senescence reversal in HDFs and the relatedness of the stereoisomer Rg3(R) in corresponding signaling pathways are not known yet. Methods: We performed senescence-associated β-galactosidase and cell cycle assays in Rg3(S)-treated senescent HDFs. The levels of ROS, adenosine triphosphate (ATP), and cyclic adenosine monophosphate (cAMP) as well as the mitochondrial DNA copy number, nicotinamide adenine dinucleotide (NAD)⁺/1,4-dihydronicotinamide adenine dinucleotide (NADH) ratio, and NAD-dependent sirtuins expression were measured and compared among young, old, and Rg3(S)-pretreated old HDFs. Major signaling pathways of phosphatidylinositol 3-kinase/Akt, 5' adenosine monophosphate-activated protein kinase (AMPK), and sirtuin 1/3, including cell cycle regulatory proteins, were examined by immunoblot analysis. Results: Ginsenoside Rg3(S) reversed the replicative senescence of HDFs by restoring the ATP level and NAD⁺/NADH ratio in downregulated senescent HDFs. Rg3(S) recovered directly the cellular levels of ROS and the NAD⁺/NADH ratio in young HDFs inactivated by rotenone. Rg3(S) mainly downregulated phosphatidylinositol 3-kinase/Akt through the inhibition of mTOR by cell cycle regulators like p53/p21 in senescent HDFs, whereas Rg3(R) did not alter the corresponding signaling pathways. Rg3(S)-activated sirtuin 3/PGC1α to stimulate mitochondrial biogenesis. Conclusion: Cellular molecular analysis suggests that Rg3(S) specifically reverses the replicative senescence of HDFs by modulating Akt-mTOR-sirtuin signaling to promote the biogenesis of mitochondria.

• Food Science and Preservation
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• v.16 no.5
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• pp.754-758
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• 2009

To develop soybean cake as a functional food material, the anti-oxidative and cytotoxic activities against human colon cancer cells of crude saponins isolated from 70% (v/v) ethanol extracts of cake were investigated. The Diaion HP-20 adsorption method was used for isolation of crude saponins, which were then eluted with 100% ethanol. The non-saponin fraction was removed by elution with $H_2O$ and 20% (v/v) ethanol. The results of thin layer chromatography (TLC) analysis confirmed that crude saponins were present in the 100% ethanol extract of soybean cake. The hydrogen-donating properties of saponins were more than 60% at a concentration of $1,000\;{\mu}g/mL$. malondialdehyde(MDA) production was $1,200\;{\mu}mol\;MDA/g$ in mouse liver homogenate treated with crude saponins at the concentration of $1,000\;{\mu}g/mL$. This value was lower than that of the control, which was $3,700\;{\mu}mol\;MDA/g$. Saponins inhibited the growth of colon cancer cells in a dose- and time-dependent manner. Saponins also resulted in a decrease in the proportion of cells in the G1 phase of the cell cycle, whereas the cell proportion in G2/M phase was increased with $1,000\;{\mu}g/mL$ saponins. Thus, we conclude that saponins may induce G2/M cell cycle arrest.