• Journal of Radiation Industry
• /
• v.17 no.3
• /
• pp.257-264
• /
• 2023

This study was conducted to evaluate the applicability of the Comet assay, which is widely used for the identification of irradiated meats, to detect irradiated beef cut, ground beef, and Tteokgalbi during freezing storage. Gamma-irradiation significantly increased the DNA damage in frozen beef cut and ground beef samples. Among those, DNA nuclei of samples irradiated with absorbed doses of 1kGy or more showed typical comet-shaped damage, convincing that the samples were irradiated. Meanwhile, DNA nuclei in non-irradiated beef cut and ground beef samples were also damaged according to storage time. In particular, since the damage of DNA nuclei in the non-irradiated samples frozen for three months was similar to that of samples irradiated with a dose of 0.5 kGy, it was considered difficult to detect whether these samples were irradiated by Comet assay analysis. Likewise, gamma-irradiation of Tteokgalbi increased DNA damage. However, significant damage to DNA nuclei was observed even in the non-irradiated samples. Therefore, the application of the analysis method to determine whether the Tteokgalbi sample was irradiated was not appropriate. In conclusion, these results suggest that Comet assay could be limitedly applied only to fresh meat with a short storage period and minimal processing.

• Biomolecules & Therapeutics
• /
• v.19 no.3
• /
• pp.308-314
• /
• 2011

It has been shown that circadian genes not only play an important role on circadian rhythms, but also participate in other physiological and pathological activities, such as drug dependence, cancer development and radiation injury. The Per2, an indispensable component of the circadian clock, not only modulates circadian oscillations, but also regulates organic function. In the present study, we applied mPER2-upregulated NIH3T3 cells to reveal the relationship of mPer2 and the cells damaged by ultraviolet C (UVC). NIH3T3 cells at the peak of the expression of mPer2 induced by phorbol 12-myristate 13-acetate (PMA) demonstrated little damage by UVC evaluated by MTT assay, cell growth curves and cell colony-forming assay, compared with that at the nadir of the expression of mPer2. Overexpression of mPER2, accompanied p53 upregulated, also demonstrated protective effect on NIH3T3 cells damaged by UVC. These results suggest that mPer2 plays a protective effect on cells damaged by UVC, whose mechanism may be involved in upregulated p53.

• Journal of Photoscience
• /
• v.9 no.2
• /
• pp.454-456
• /
• 2002

It is important to determine the action spectrum of UV-B radiation contained in the sunlight to estimate the risk of skin cancer. We have investigated action spectra for induction of apoptosis and reproductive cell death in L5178Y cells using the Okazaki Large Spectrograph at NIBB. L5178Y cells were exposed to light at different wavelengths in UV-B or UV-A region. Frequencies of apoptosis induction and reproductive cell death were determined by counting cells with chromatin condensation, and by the colony formation assay, respectively. The measured sensitivity spectra for the two end-points were in very good agreement. Sensitivity decreased steeply with increase of wavelength in UV-B region and remains nearly constant in UV-A region. The action spectra were also slightly steeper than that for the minimum erythematic dose (MED), but very similar to the light absorption spectrum of DNA in UV-B region. On the other hand, the spectra for both endpoints were similar to MED spectrum but not DNA spectrum in the UV-A region. Also different time-course and morphological difference of apoptosis were found between UV-B (long time, fragmentation) and UV-A (short time, shrinkage) region. These results suggest that DNA damage induced by UV-B light triggers apoptosis and reproductive cell death, but other damaged targets (membrane, protein and so on) trigger these effects in UV-A region.

• Journal of Sasang Constitutional Medicine
• /
• v.14 no.1
• /
• pp.79-89
• /
• 2002

To evaluate the effect of Yuldahansotang(YHT) water extract on cultured hippocampal cell was inhibited by hydrogen peroxide, MTT assay, NR assay, Neurofilament enzymeimmuno assay and DNA synthesis assay were carried out after the cultured hippocampal cells were preincubated with various concentrations of YHT water extract for 3 hours prior to exposure of hydrogen peroxide. The results obtained were as follows: 1. Hydrogen Peroxide decreased the survival rate of the cultured hippocampal cells on NR assay and MIT assay. 2. YHT water extract have efficacy of increasing a amount of neurofilament decreased by hydrogen peroxide in cultured hippocampal cells. 3. YHT water extract have efficacy of increasing DNA synthesis decreased by hydrogen peroxide in cultured hippocampal cells. From above the results, It is concluded that YHT has marked efficacy in preventing for the damages by hydrogen peroxide.

• Journal of Animal Reproduction and Biotechnology
• /
• v.36 no.4
• /
• pp.253-260
• /
• 2021

Organ transplantation is currently the most fundamental treatment for organ failure, but there is a shortage of organ supply compared to those in need. Regenerative medicine has recently developed a decellularization technique that overcomes the limitations of conventional organ transplantation and attempts to reconstruct damaged tissues or organs to their normal state. Several decellularization methods have been suggested. In this experiment, the decellularization methods were used to find effective decellularization methods for humanlike porcine placenta. The optimal conditions for decellular support are low DNA content and high glycos amino glycans (GAGs) and collagen content. In order to satisfy this condition, SDS and Triton X-100 and SDS + Triton X-100 were used as the detergent used for decellularization in this experiment. The contents were compared according to the decellularization time (0, 12, 24, 48 and 72 hours), and the concentrations of SDS (0.2, 0.5, 0.7 and 1.0%) were mixed in 1.0% Triton X-100 to analyze the contents. When decellularized using SDS and Triton X-100, respectively, it was confirmed that the contents of DNA and GAGs were opposite to each other. And decellularization treatment for 24 hours at 0.5% SDS was able to obtain an effective decellular support. If decellularization studies of various detergents can be obtained an effective decellular support, and furthermore, cell culture experiments can confirm the effect on the cells.

• BMB Reports
• /
• v.56 no.5
• /
• pp.302-307
• /
• 2023

Lyn, a tyrosine kinase that is activated by double-stranded DNA-damaging agents, is involved in various signaling pathways, such as proliferation, apoptosis, and DNA repair. Ribosomal protein S3 (RpS3) is involved in protein biosynthesis as a component of the ribosome complex and possesses endonuclease activity to repair damaged DNA. Herein, we demonstrated that rpS3 and Lyn interact with each other, and the phosphorylation of rpS3 by Lyn, causing ribosome heterogeneity, upregulates the translation of p-glycoprotein, which is a gene product of multidrug resistance gene 1. In addition, we found that two different regions of the rpS3 protein are associated with the SH1 and SH3 domains of Lyn. An in vitro immunocomplex kinase assay indicated that the rpS3 protein acts as a substrate for Lyn, which phosphorylates the Y167 residue of rpS3. Furthermore, by adding various kinase inhibitors, we confirmed that the phosphorylation status of rpS3 was regulated by both Lyn and doxorubicin, and the phosphorylation of rpS3 by Lyn increased drug resistance in cells by upregulating p-glycoprotein translation.

• Korean Journal of Plant Resources
• /
• v.22 no.5
• /
• pp.461-466
• /
• 2009

This study was carried out to evaluate the effects of yam (Dioscorea batatas Dence) extracts on the cell viability, growth and nucleus-DNA damage of tobacco cells which were exposed to $\gamma$-radiation stress. The viability and growth of tobacco cells exposed to 20 Gy of radiation stress were effectively recovered by pretreatment of 10 mg/L ethylacetate (EtOAc) yam extract. Pretreatment of EtOAc extract showed 20% higher cell viability and fresh weight growth than that of cells without pretreatment in 20 Gy radiation treated tobacco cells. Nucleus-DNA damage was measured as the ratio of tail length (T) to head length (H) in individual comet image isolated from tobacco cells. The T/H ratio of control-cells and treated-cells at 20 Gy were 1.05 and 1.68, and % head DNA of those cell were 86.7 and 71.3%, respectively, suggesting that nuclei of tobacco cells were severely damaged in the integrity of DNA by the treatment of $\gamma$-radiation. However, pretreatment of MeOH, EtOAc and n-BuOH extracts decreased radiation induced DNA-damage in the tobacco cells, showing T/H ratio of 1.37, 1.01 and 1.10 and % head DNA of 81.5, 87.6 and 88.7%, respectively.

• Journal of Radiation Protection and Research
• /
• v.45 no.4
• /
• pp.163-170
• /
• 2020

Background: Gut microflora contributes to the nutritional metabolism of the host and to strengthen its immune system. However, if the intestinal barrier function of the living body is destroyed by radiation exposure, the intestinal bacteria harm the health of the host and cause sepsis. Therefore, this study aims to trace short-term radiation-induced changes in the mouse gut microflora-dominant bacterial genus, and analyze the degree of intestinal epithelial damage. Materials and Methods: Mice were irradiated with 0, 2, 4, 8 Gy X-rays, and the gut microflora and intestinal epithelial changes were analyzed 72 hours later. Five representative genera of Actinobacteria, Firmicutes, and Bacteroidetes were analyzed in fecal samples, and the intestine was pathologically analyzed by Hematoxylin-Eosin and Alcian blue staining. In addition, DNA fragmentation was evaluated by the TdT-mediated dUTP nick-end labeling (TUNEL) assay. Results and Discussion: The small intestine showed shortened villi and reduced number of goblet cells upon 8 Gy irradiation. The large intestine epithelium showed no significant morphological changes, but the number of goblet cells were reduced in a radiation dose-dependent manner. Moreover, the small intestinal epithelium of 8 Gy-irradiated mice showed significant DNA damaged, whereas the large intestine epithelium was damaged in a dose-dependent manner. Overall, the large intestine epithelium showed less recovery potential upon radiation exposure than the small intestinal epithelium. Analysis of the intestinal flora revealed fluctuations in lactic acid bacteria excretion after irradiation regardless of the morphological changes of intestinal epithelium. Altogether, it became clear that radiation exposure could cause an immediate change of their excretion. Conclusion: This study revealed changes in the intestinal epithelium and intestinal microbiota that may pave the way for the identification of novel biomarkers of radiation-induced gastrointestinal disorders and develop new therapeutic strategies to treat patients with acute radiation syndrome.

• Journal of Food Hygiene and Safety
• /
• v.18 no.1
• /
• pp.6-13
• /
• 2003

Various kinds of genetically modified organisms (GMO) and processed foods have been developed during recent years. Genetically modified organisms can be classified into several groups as their development methods. Generally, GMO has three foreign DNA regions such as gene expression adjustment region(Promoter), termination region (terminator) and structure gene. Detection of these regions can be done particularly by polymerase chain reaction (PCR). PCR-based detection can virtually be performed for any GMO within short of time. The most important prerequisite for the application of PCR-based detection is to decide abstraction method of efficient nucleic acids. Specially, in the case of processed food, because nucleic acids of foodstuffs are damaged by heat treatment (sterilization), pressure and fermentation, DNA must be extracted ken the samples prior to PCR analysis. Although many DNA extraction protocols are available, they have rarely been compared in a comprehensive method. In this study low widely used commercial and non-commercial DNA extraction methods-DNeasy$^{TM}$, Wizard$^{TM}$, CTAB, phenol/chloroform system-were compared with respect to the quality and yield of nucleic acids and insertion genes.nes.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.10
• /
• pp.4993-4998
• /
• 2012

Vanillic acid, a vegetable phenolic compound, is a strong antioxidant. The aim of the present study was to determine its effects on mitomycin C-induced DNA damage in human blood lymphocyte cultures in vitro, both alone and in combination with mitomycin C (MMC). The cytokinesis block micronucleus test and alkaline comet assay were used to determine genotoxic damage and anti-genotoxic effects of vanillic acid at the DNA and chromosome levels. MMC induced genotoxicity at a dose of $0.25{\mu}g/ml$. Vanillic acid ($1{\mu}g/ml$) significantly reduced both the rates of DNA damaged cells and the frequency of micronucleated cells. A high dose of vanillic acid ($2{\mu}g/ml$) itself had genotoxic effects on DNA. In addition, both test systems showed similar results when tested with the negative control, consisting of dimethyl sulfoxide (DMSO) in combination with vanillic acid ($1{\mu}g/ml$)+MMC. In conclusion, vanillic acid could prevent oxidative damage to DNA and chromosomes when used at an appropriately low dose.