• Title/Summary/Keyword: cell membrane damage

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Increased Apoptotic Efficacy of Decitabine in Combination with an NF-kappaB Inhibitor in Human Gastric Cancer AGS Cells (핵산합성 억제제인 decitabine과 NF-κB 활성 저해제인 PDTC의 병용 처리에 의한 인체 위암세포사멸 효과 증진)

  • Choe, Won Kyung;Choi, Yung Hyun
    • Journal of Life Science
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    • v.28 no.11
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    • pp.1268-1276
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    • 2018
  • The cytidine analog decitabine (DEC) acts as a nucleic acid synthesis inhibitor, whereas ammonium pyrrolidine dithiocarbamate (PDTC) is an inhibitor of nuclear factor-${\kappa}B$. The aim of this study was to investigate the possible synergistic inhibitory effect of these two inhibitors on proliferation of human gastric cancer AGS cells. The inhibitory effect of PDTC on AGS cell proliferation was significantly increased by DEC in a concentration-dependent manner, and this inhibition was associated with cell cycle arrest at the G2/M phase and the induction of apoptosis. This induction of apoptosis by the co-treatment with PDTC and DEC was related to the induction of DNA damage, as assessed by H2AX phosphorylation. Further studies demonstrated that co-treatment with PDTC and DEC induced the disruption of mitochondrial membrane potential, increased the generation of intracellular reactive oxygen species (ROS) and the expression of pro-apoptotic Bax, and down-regulated the expression of anti-apoptotic Bcl-2, ultimately resulting in the release of cytochrome c from the mitochondria into the cytoplasm. Co-treatment with PDTC and DEC also activated caspase-8 and caspase-9, which are representative caspases of the extrinsic and intrinsic apoptosis pathways. Co-treatment also activated caspase-3, which was accompanied by proteolytic degradation of poly (ADP-ribose) polymerase. Taken together, these data clearly indicated that co-treatment with PDTC and DEC suppressed the proliferation of AGS cells by increasing DNA damage and activating the ROS-mediated extrinsic and intrinsic apoptosis pathways.

Studies on the Function of Taurine: Review (사람의 체내에서 타우린의 역할에 관한 연구)

  • Yoon, Jin A;Shin, Kyung-Ok;Choi, Kyung-Soon
    • The Korean Journal of Food And Nutrition
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    • v.28 no.5
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    • pp.880-893
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    • 2015
  • Taurine is an abundant amino acid in many animals, including humans. Relatively large amounts of taurine are found in leukocytes, heart, muscles, retinas, kidneys, bones, and liver. Taurine has antioxidant effects; it reacts with hydrogen peroxide to prevent oxidation of the cell membrane. Taurine enhances the effects of anticancer drugs, while also reducing side effects, and taurolidine, a taurine derivative, has been shown to exhibit anti-cancer effects without notable side effects in several types of cancer. Taurine aids in cholesterol metabolism by increasing the rate of synthesis of bile acids, and, thus, reduces triglyceride levels. In addition, taurine is involved in the growth and differentiation of nerve cells and is associated with some neurological disorders. Taurine aids in bone formation and prevents bone dissolution. Moreover, taurine prevents liver damage from a variety of drugs and, thus, protects the liver. Taurine is involved in the development and function of the retina and lens. It also has anti-atherosclerotic and anti-thrombotic effects that protect against cardiovascular disease. Taurine may have additional physiological functions, and warrants further investigation.

Hesperidin Attenuates Ultraviolet B-Induced Apoptosis by Mitigating Oxidative Stress in Human Keratinocytes

  • Hewage, Susara Ruwan Kumara Madduma;Piao, Mei Jing;Kang, Kyoung Ah;Ryu, Yea Seong;Han, Xia;Oh, Min Chang;Jung, Uhee;Kim, In Gyu;Hyun, Jin Won
    • Biomolecules & Therapeutics
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    • v.24 no.3
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    • pp.312-319
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    • 2016
  • Human skin cells undergo pathophysiological processes via generation of reactive oxygen species (ROS) upon excessive exposure to ultraviolet B (UVB) radiation. This study investigated the ability of hesperidin ($C_{28}H_{34}O_{15}$) to prevent apoptosis due to oxidative stress generated through UVB-induced ROS. Hesperidin significantly scavenged ROS generated by UVB radiation, attenuated the oxidation of cellular macromolecules, established mitochondrial membrane polarization, and prevented the release of cytochrome c into the cytosol. Hesperidin downregulated expression of caspase-9, caspase-3, and Bcl-2-associated X protein, and upregulated expression of B-cell lymphoma 2. Hesperidin absorbed wavelengths of light within the UVB range. In summary, hesperidin shielded human keratinocytes from UVB radiation-induced damage and apoptosis via its antioxidant and UVB absorption properties.

Early Detection of Peripheral Intravenous Infiltration Using Segmental Bioelectrical Impedance: Preliminary Study

  • Kim, Jaehyung;Jeong, Ihnsook;Baik, Seungwan;Jeon, Gyerok
    • Journal of Korea Multimedia Society
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    • v.20 no.3
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    • pp.482-490
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    • 2017
  • Early detection of infiltration is one of the most important tasks of nurses to minimize skin damage due to infiltration. For subjects receiving invasive intravenous treatment, the bioelectrical impedance (impedance) were measured in the frequency range of 5 to 500 kHz using bioelectrical impedance spectroscopy (BIS). After attaching electrodes at both ends of a transparent dressing mounted on the skin in which IV solution was infused into the vein, the change in impedance was measured as a function of time and frequency before and after infiltration. The experimental results are described as follows. When IV solution was properly infused into the vein, the impedance was nearly constant over time and decreased with increasing frequency. However, when infiltration occurred, the impedance decreased significantly and thereafter gradually decreased with time. In addition, impedance decreased with time for all applied frequencies. In this study, when IV solution penetrated into the surrounding skin and subcutaneous tissue by infiltration, impedance was quantitatively analyzed for as a function of time and frequency. This suggests a method for early detection of infiltration using BIS.

A Detection of Airborne Particles Carrying Viable Bacteria in an Urban Atmosphere of Japan

  • Hara, Kazutaka;Zhang, Daizhou;Yamada, Maromu;Matsusaki, Hiromi;Arizono, Koji
    • Asian Journal of Atmospheric Environment
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    • v.5 no.3
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    • pp.152-156
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    • 2011
  • Viable bacteria on water-insoluble airborne particles were detected in the urban atmosphere of Kumamoto ($134^{\circ}45'E$, $32^{\circ}28'N$), Japan, in autumn 2008. Airborne particles were collected onto film-covered Cu meshes under clear weather conditions. The samples were stained by fluorescent stains, and then viewed and photographed with an epifluorescent microscope. Non-biological and bacterial parts in particles larger than 0.8 ${\mu}m$ were distinguished by their morphologies, fluorescent colors and fluorescent intensities. Bacterial viable statuses were discriminated according to cell membrane damage. In total, 2681 particles were investigated and it was found that 78 airborne particles were associated with bacteria. Viable bacteria were identified on 48 particles. A few particles carried multiple viable bacteria. These results provide the evidence that airborne particles act as carriers of viable bacteria in the atmosphere.

A Conclusive Review on Amyloid Beta Peptide Induced Cerebrovascular Degeneration and the Mechanism in Mitochondria

  • Merlin, Jayalal L.P.
    • Journal of Integrative Natural Science
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    • v.6 no.3
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    • pp.125-137
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    • 2013
  • Promising evidence suggests that amyloid beta peptide ($A{\beta}$), a key mediator in age-dependent neuronal and cerebrovascular degeneration, activates death signalling processes leading to neuronal as well as non-neuronal cell death in the central nervous system. A major cellular event in $A{\beta}$-induced apoptosis of non-neuronal cells, including cerebral endothelial cells, astrocytes and oligodendrocytes, is mitochondrial dysfunction. The apoptosis signalling cascade upstream of mitochondria entails $A{\beta}$ activation of neutral sphingomyelinase, resulting in the release of ceramide from membrane sphingomyelin. Ceramide then activates protein phosphatase 2A (PP2A), a member in the ceramide-activated protein phosphatase (CAPP) family. PP2A dephosphorylation of Akt and FKHRL1 plays a pivotal role in $A{\beta}$-induced Bad translocation to mitochondria and transactivation of Bim. Bad and Bim are pro-apoptotic proteins that cause mitochondrial dysfunction characterized by excessive ROS formation, mitochondrial DNA (mtDNA) damage, and release of mitochondrial apoptotic proteins including cytochrome c, apoptosis inducing factor (AIF), endonuclease G and Smac. The cellular events activated by $A{\beta}$ to induce death of non-neuronal cells are complex. Understanding these apoptosis signalling processes will aid in the development of more effective strategies to slow down age-dependent cerebrovascular degeneration caused by progressive cerebrovascular $A{\beta}$ deposition.

A Ferroxidase, Cfo1, Regulates Diverse Environmental Stress Responses of Cryptococcus neoformans through the HOG Pathway

  • Lee, Kyung-Tae;Lee, Jang-Won;Lee, Dohyun;Jung, Won-Hee;Bahn, Yong-Sun
    • Mycobiology
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    • v.42 no.2
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    • pp.152-157
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    • 2014
  • The iron uptake and utilization pathways play a critical role in allowing human pathogens, including Cryptococcus neoformans, the causative agent of fatal meningoencephalitis, to survive within the mammalian body by competing with the host for iron. Here we show that the iron regulon is also required for diverse environmental stress responses and that in C. neoformans, it is regulated by the high-osmolarity glycerol response (HOG) pathway. Between CFO1 and CFO2, two ferroxidase genes in the iron regulon, CFO1 but not CFO2 was induced during oxidative and osmotic stress. Interestingly, we found that the HOG pathway repressed basal expression of both CFO1 and CFO2. Furthermore, when the HOG pathway was blocked, CFO2 also responded to oxidative and osmotic stress and the response of CFO1 was increased. We also established that CFO1 plays a major role in responding and adapting to diverse environmental stresses, including oxidative and genotoxic damage, osmotic fluctuations, heavy metal stress, and stress induced by cell membrane destabilizers. Therefore, our findings indicate that in C. neoformans, the iron uptake and utilization pathways are not only required for iron acquisition and survival, but also play a significant role in the environmental stress response through crosstalk with the HOG pathway.

Garlic-induced Hematologic Effects in Small dogs (소형견에서 마늘투여가 혈액상에 미치는 영향)

  • ;;;;;;;Osamu Yamato;Yoshimitsu Maede
    • Journal of Veterinary Clinics
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    • v.16 no.2
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    • pp.276-280
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    • 1999
  • It is well-known that onion and garlic of Allium family have been cultivated for major food since ancient times. Especially garlic is known for containing protective materials against cardiovascular disease, neoplasm and cancer, and decreasing cholesterol value. Hemolytic anemia was first reported by Goldsmith in onion-fed cattle in 1909. Subsequently, similar effects have been reported in cattle, horses, sheep, dogs and cats. This toxic effect has been attributed to npropyl disulfide which causes oxidant damage to erythrocyte cell membrane. There are few reports on overconsumption of garlic. Kim et al. reported in 1999 that 45% of Jindo dogs in korea have erythrocytes characterized by high Na-K-ATPase activity with high K and low Na concentrations (HK) which easily results in hemolytic anemia. The purpose of present report is to determine whether garlic-induced hemolytic anemia occurs in normal erythrocytes characterized by complete lack of Na-K-ATPase activity with low K and high Na concentrations (LK) when LK dogs are fed large amounts of garlics. We found in this experiment that Erythrocyte count, PCV and Hemoglobin concentration decreased significantly, and GSH and Met-hemoglobin concentrations increased. Consequently, we determined that overconsumption of garlic induces hemolytic anemia in LK dogs.

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Evaluate of Electrochemical Characteristics in Electrolyzed Reduced Water

  • Park, Sung-Ho;Yun, Su-Jin;Kim, Jeong-Sik;Shin, Hyun-Su;Park, Soo-Gil
    • Journal of Electrochemical Science and Technology
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    • v.2 no.2
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    • pp.85-90
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    • 2011
  • Active oxygen species or free radicals are considered to cause extensive oxidative damage to biological macromolecules, which brings about a variety of diseases as well as aging. Electrolyzed reduced water(ERW) has been regarded as a ideal antioxidative agent in recent years. ERW is produced by passing a diluted salt solution through an electrolytic cell, within which the anode and cathode are separated by membrane. It can be produced reactive materials in ERW near the cathode during the electrolysis of water. ERW have the following advantages over other traditional cleaning agents: effective antioxidative agent, easy preparation, inexpensive, and environmentally friendly. The main advantage of ERW is its safety and antioxidative effect. ERW with strong reducing potential can be used to remove dirt and grease from items such as cutting boards and other kitchen utensils. The primary aim of this study is the activation mechanism of oxidation reduction potentials, ion conductivity, pH, and electrochemical properties with reactive materials in ERW.

Disinfection by Ozone Microbubbles Can Cause Morphological Change of Fusarium oxysporum f. sp. melonis Spores

  • Tamaki, Masahiko;Kobayashi, Fumiyuki;Ikeura, Hiromi;Sato, Michio
    • The Plant Pathology Journal
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    • v.34 no.4
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    • pp.335-340
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    • 2018
  • To investigate the difference in the disinfectant efficiency of ozone microbubbles ($O_3MB$) and ozone millibubbles ($O_3MMB$), the morphological change of the treated Fusarium oxysporum f. sp. melonis spores was observed with scanning and transmission electron microscopies (SEM and TEM). The disinfectant efficiency of $O_3MB$ on F. oxysporum f. sp. melonis spores was greater than that of $O_3MMB$. On observation with SEM, it was revealed that morphological change of F. oxysporum f. sp. melonis spores was caused by $O_3MB$ and $O_3MMB$, and damage to the spore surfaces by $O_3MB$ occurred sooner than that by $O_3MMB$. On observation with TEM, it was furthermore confirmed that F. oxysporum f. sp. melonis spores treated with $O_3MB$ induced wavy deformation of cell membrane and the intracellular change different from that with $O_3MMB$. Therefore, the greater disinfection efficiency of $O_3MB$ was suggested to be caused due to the function of the MB in addition to the oxidative power of $O_3$.