• Asian Pacific Journal of Cancer Prevention
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• v.15 no.11
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• pp.4405-4409
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• 2014

Reactive oxygen species (ROS), highly reactive molecules, are produced by living organisms as a result of normal cellular metabolism and environmental factors, and can damage nucleic acids and proteins, thereby altering their functions. The human body has several mechanisms to counteract oxidative stress by producing antioxidants. A shift in the balance between oxidants and antioxidants in favor of oxidants is termed as "oxidative stress". Paradoxically, there is a large body of research demonstrating the general effect of oxidative stress on signaling pathways, less is known about the initial and direct regulation of signaling molecules by ROS, or what we term the "oxidative interface." This review focuses on the molecular mechanisms through which ROS directly interact with critical signaling molecules to initiate signaling in a broad variety of cellular processes, such as proliferation and survival (MAP kinases and PI3 kinase), ROS homeostasis, and antioxidant gene regulation (Ref-1 and Nrf-2). This review also deals with classification as well as mechanisms of formation of free radicals, examining their beneficial and deleterious effects on cellular activities and focusing on the potential role of antioxidants in preventing and repairing damage caused by oxidative stress. A discussion of the role of phytochemical antioxidants in oxidative stress, disease and the epigenome is included.

• BMB Reports
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• v.53 no.5
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• pp.248-253
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• 2020

Gene expression in HIV-1 is regulated by the promoters in 5' long-terminal repeat (LTR) element, which contain multiple DNA regulatory elements that serve as binding sites for cellular transcription factors. YY1 could repress HIV-1 gene expression and latent infection. Here, however, we observed that virus production can be increased by YY1 over-expression and decreased under YY1 depleted condition by siRNA treatment. To identify functional domain(s) of YY1 activation, we constructed a number of YY1 truncated mutants. Our data show that full-length YY1 enhances the viral transcription both through U3 and U3RU5 promoters. Moreover, the C-terminal region (296-414 residues) of YY1 is responsible for the transcriptional upregulation, which could be enhanced further in the presence of the viral Tat protein. The central domain of YY1 (155-295 residues) does not affect LTR activity but has a negative effect on HIV-1 gene expression. Taken together, our study shows that YY1 could act as a transcriptional activator in HIV-1 replication, at least in the early stages of infection.

• Journal of Microbiology and Biotechnology
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• v.28 no.1
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• pp.22-31
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• 2018

Isoflavone itself is less available in the body without the aid of intestinal bacteria. In this study, we searched for isoflavone-transforming bacteria from human fecal specimens (n = 14) using differential selection media. Isoflavone-transforming activity as the production of dihydrogenistein and dihydrodaidzein was assessed by high-performance liquid chromatography and we found Lactobacillus rhamnosus, named L. rhamnosus vitaP1, through 16S rDNA sequence analysis. Extract from Pueraria lobata (EPL) and soy hypocotyl extract were fermented with L. rhamnosus vitaP1 for 24 and 48 h at $37^{\circ}C$. Fermented EPL (FEPL) showed enhanced anti-tyrosinase activity and antioxidant capacities, important suppressors of the pigmentation process, compared with that of EPL (p < 0.05). At up to $500{\mu}g/ml$ of FEPL, there were no significant cell cytotoxicity and proliferation on B16-F10 melanoma cells. FEPL ($100{\mu}g/ml$) could highly suppress the content of melanin and melanosome formation in B16-F10 cells. In summary, Lactobacillus rhamnosus vitaP1 was found to be able to biotransform isoflavones in EPL. FEPL showed augmented anti-melanogenic potential.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.5
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• pp.2395-2399
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• 2016

Background: Hepatitis B virus (HBV) is a major risk factor for hepatocellular carcinoma (HCC). Cytokines play an important role in the regulation of immune responses and defense against viral infections. Human interleukin 6 (IL6) is a multifunctional cytokine that participates in these processes. Objective: The aim of this study was to assess the IL6-174 gene polymorphism in patients with chronic hepatitis B virus (HBV) infection as compared with healthy controls in an Iranian population. Materials and Methods: Totals of 297 HBV patients and 368 control individuals were evaluated. Genomic DNA was extracted from peripheral blood and the SSP-PCR (sequence specific primer-polymerase chain reaction) method was applied for genotyping. Results: The frequencies of genotypes C/C, G/G and C/G in HBV cases were 4.7%, 34.3%, 60.9% and in controls were 12.8%, 39.7% and 47.6%, respectively. The frequencies of G and C allele in patients and controls were 78.1%, 21.9% and 67.4%, 32.6 % respectively. There was a significant difference in the frequencies of G/G genotype (CI=1.8-7.1, OR=3.47, P=0.00001) and G allele (CI=1.34-2.23, OR=1.72, P=0.0001) between HBV patients and the control group. Conclusions: These findings suggest that the IL6-174 C/G genotype and the G allele are strongly associated with susceptibility to HBV infection. Demographic information showed that most of the subjects were male (74.4%). According to high frequency of G/G genotype in male participants (63.1%) men probably are more susceptible to hepatitis than women.

• Journal of Dairy Science and Biotechnology
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• v.33 no.3
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• pp.197-202
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• 2015

While various foodborne pathogenic bacteria can be detected more rapidly via polymerase chain reaction than via conventional plating methods, it is impossible to distinguish between viable and dead cells in DNA-based assays. Hence, propidium monoazide (PMA) treatment has been introduced to detect living cells. The purpose of this study is to evaluate the applicability of the PMA treatment and real-time qPCR method for the detection of Cronobacter sakazakii and to compare it to that of plate counting. Based on our positive results, we suggest the use of PMA treatment and real-time qPCR for the detection of viable Cronobacter sakazakii in various food sources and an update of the Korean Food Code.

• Journal of Life Science
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• v.8 no.3
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• pp.249-256
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• 1998

The purpose of this study was to understand the evolutionary relationships between fish and other vertebrates which had DNA with the genetic defects in homoglobin expression, with comparison to the nucleotide homologies of the ${\beta}$-globin genes. The predicted amino acid sequence from carp ${\beta}$-globin gene was compared with those of other vertebrates from the published data. The nucleotide homologies of the predicted amino acid sequence from the carp ${\beta}$-globin gene with those of goldfish and mirror carp were high, and the rates were 97.3% and 93.9%, respectively. On the other hand, with the previously reported ${\beta}$-globins of goat, frog, human, rat, goose, chicken, and duck, it showed low homology ranging from 45.9 to 58.1%. The carp ${\beta}$-globin has one inserted amino acid residue, which was also found in other fish ${\beta}$globin, but not in other vertebrate ${\beta}$-globins.

• Journal of Plant Biotechnology
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• v.35 no.4
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• pp.329-335
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• 2008

Tocopherols are essential lipophilic antioxidant in human cells, while little is known about its function in plant tissues. To study the impact of composition and content of tocopherols on stress tolerance, tobacco (Nicotiana tabacum) was transformed with a construct containing a cDNA insert encoding $\gamma$-tocopherol methyltransferase ($\gamma$-TMT/VTE4) from perilla under the control of the cauliflower mosaic virus (CaMV) 35S promoter. The transgenic tobacco was confirmed by PCR and RT-PCR. The total content and composition of tocopherols in the transgenic lines were similar with wild type controls. However, chlorophyll-a and carotenoid content in the transgenic lines were increased by up to 45% (P<0.01) and 39% (P<0.02), respectively. Also, the over-expression of $\gamma$-TMT increased the salt stress tolerance in tobacco plants. These results demonstrate that over-expression of $\gamma$-TMT gene in tocopherol bio-synthetic pathway can increase salt stress tolerance and contents of chlorophyll-a and carotenoid in transgenic tobacco plants.

• Journal of Environmental Science International
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• v.16 no.2
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• pp.219-225
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• 2007

Endocrine disrupting compounds (EDC's) are chemicals that either mimic endogenous hormones interfering with pharmacokinetics or act by other mechanisms. Some endocrine disrupters were reported to be chemical substances that cause apoptosis in cells. A number of reports have indicated that 1,3-DCP, one of the EDC's may act as an endocrine disrupter and also has possible carcinogenic effects. 1,3-DCP, present in commercial protein hydrolysates used for human nutrition, are genotoxic and 1,3-dichloro-2-propanol induced tumors in rats. In the present study, it was investigated whether 1,3-DCP induces ROS generation and apotosis in A549 adenocarcinoma cells. Here we show that 1,3-DCP inhibits the growth of lung cancer cell lines and generates reactive oxygen species (ROS), a major cause of DNA damage and genetic instability, It was investigated that 1,3-DCP increases G1 phase cells after 12 hours, thereafter abruptly draws A549 cells to G0 state after 24 hours by flow cytometric analysis. 1,3-DCP induces p53 and $p21^{Cip1/WAF1}$ activation time- and dose-dependently by 24 hours, while the level $p21^{Cip1/WAF1}$ was decreased after 48 hours. These results suggest that 1,3-DCP, an EDC's generates ROS and regulates genes involved with cell cycle and apoptosis.

• International Journal of Oral Biology
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• v.36 no.1
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• pp.13-21
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• 2011

Chios gum mastic (CGM) is produced from Pistiacia lentiscus L var chia, which grows only on Chios Island in Greece. CGM is a kind of resin extracted from the stem and leaves, has been used for many centuries in many Mediterranean countries as a dietary supplement and folk medicine for stomach and duodenal ulcers. CGM is known to induce cell cycle arrest and apoptosis in some cancer cells. This study was undertaken to investigate the alteration of the cell cycle and induction of apoptosis following CGM treatment of HL-60 cells. The viability of the HL-60 cells was assessed using the MTT assay. Hoechst staining and DNA electrophoresis were employed to detect HL-60 cells undergoing apoptosis. Western blotting, immunocytochemistry, confocal microscopy, FACScan flow cytometry, MMP activity and proteasome activity analyses were also employed. CGM treatment of HL-60 cells was found to result in a dose- and time-dependent decrease in cell viability and apoptotic cell death. Tested HL-60 cells showed a variety of apoptotic manifestations and induced the downregulation of G1 cell cycle-related proteins. Taken collectively, our present findings demonstrate that CGM strongly induces G1 cell cycle arrest via the modulation of cell cycle-related proteins, and also apoptosis via proteasome, mitochondrial and caspase cascades in HL-60 cells. Hence, we provide evidence that a natural product, CGM could be considered as a novel therapeutic for human leukemia.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.4
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• pp.296-303
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• 2005

A strain named as HJ35 was isolated from the skin of sixty-five men and fourteen women for acne therapy, in order to find an effective antimicrobial agent against Propionibacterium acnes. Isolate HJ35 was identified as Enterococcus faecium based on 16 rDNA sequence and produced enterocin HJ35 having antimicrobial activities against most lactic acid bacteria, En­terococcus spp., Staphylococcus aureus, S. epidermidis, Clostridium perfringens, some bacilli, Mi­crococcus flavus, Listeria monocytogenes, L. ivanovii, Escherichia coli, Pseudomonas fluorescens and Propionibacterium acnes, in the modified well diffusion method. Especially, enterocin HJ35 showed a bactericidal activity against Propionibacterium acnes P1. The antimicrobial activity of enterocin HJ35 was disappeared completely with the use of protease XIV. But enterocin HJ35 activity is very stable at high temperature (up to $100^{\circ}C$ for 30 min), in wide range of pH (3.0${\~}$9.0), and by treatment with organic solvents. The apparent molecular mass of enterocin HJ35 was estimated to be approximately 4${\~}$4.5 kDa on detection of its bactericidal activity after SDS-PAGE. In batch fermentation of E. faecium HJ35, enterocin HJ35 was produced at the mid­log growth phase, and its maximum production was obtained up to 2,300 AU/mL at the late stationary phase. By employing fed-batch fermentation, the enhanced production of enterocin HJ35 was achieved up to 12,800 AU/mL by feeding with 10 g/L glucose or 6 g/L lactate.