• Title/Summary/Keyword: Cell life span

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Research on the Power Drop of Photovoltaic Module’s Aging Through the Thermal Shock Test

  • Kang, MinSoo;Jeon, YuJae;Kim, DoSeok;Shin, YoungEui
    • Transactions on Electrical and Electronic Materials
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    • v.16 no.5
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    • pp.268-273
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    • 2015
  • While analyzing the specimens before and after the thermal shock test, we found that the power drop rate of the bare cell was 5.08%, while the power drop rate of the ribboned cell was 16.49%. In comparative terms, the efficiency was lower at the ribboned cell than at the bare cell. While analyzing through EL (Electroluminescence) shots and cross sections, we tried to decipher the exact cause of the power drop. Although mere color change of the cell was observed at the surface of the bare cell, no abnormality could be found inside the cell. On the surface of the ribboned cell, the short circuit of gridfinger extended from the front part of the front electrode of the ribboned cells. Therefore, cracks occurred on the surface of the cell. Cracks also appeared inside the cell. While analyzing the I-V curve, we determined an increase in the leakage current and an increase of resistances in series in the bare cell. In the ribboned cell, the resistances in parallel reduced remarkably. An increase of resistances in series could also be verified. Conclusively, we deduced that the power drop rate in the bare cell is a life span of the cell itself; aging is the cause of power drop rate in cells. In case of ribboned cell, the power drop rate was directly influenced by internal cracks and an intermetallic compound layer joining the ribbon at the front electrode.

Stress Responses through Heat Shock Transcription Factor in S. cerevisiae

  • Hahn, Ji-Sook;Hu, Zhanzhi;Thiele, Dennis J.;Lyer, Vishwanath R.
    • Proceedings of the Microbiological Society of Korea Conference
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    • 2005.05a
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    • pp.105-109
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    • 2005
  • Heat Shock Transcription Factor (HSF), and the promoter heat Shock Element (HSE), are among the most highly conserved transcriptional regulatory elements in nature. HSF mediates the transcriptional response of eukaryotic cells to heat, infection and inflammation, pharmacological agents, and other stresses. While HSF is essential for cell viability in yeast, oogenesis and early development in Drosophila, extended life-span in C. elegans, and extra-embryonic development and stress resistance in mammals, little is known about its full range of biological target genes. We used whole genome analyses to identify virtually all of the direct transcriptional targets of yeast HSF, representing nearly three percent of the genomic loci. The majority of the identified loci are heat-inducibly bound by yeast HSF, and the target genes encode proteins that have a broad range of biological functions including protein folding and degradation, energy generation, protein secretion, maintenance of cell integrity, small molecule transport, cell signaling, and transcription. Approximately 30% of the HSF direct target genes are also induced by the diauxic shift, in which glucose levels begin to be depleted. We demonstrate that phosphorylation of HSF by Snf1 kinase is responsible for expression of a subset of HSF targets upon glucose starvation.

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A Study on the Strategy of Smart Charging System to Charge the PHEV in the House Which has a 1 kW Fuel Cell Cogeneration System (1 kW 급 가정용 연료전지 코제너레이션 시스템이 설치된 주택 내 플러그인 하이브리드 자동차의 스마트 충전전략 연구)

  • Roh, Chul-Woo;Kim, Min-Soo
    • Proceedings of the SAREK Conference
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    • 2008.06a
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    • pp.838-843
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    • 2008
  • Cause of struggling to escape from dependency of fossil fuels, the fuel cell and the Plug-in Hybrid Electric Vehicle (PHEV) draw attention in the all of the world. Especially, the Polymer Electrolyte Membrane Fuel Cell (PEMFC) systems have been anticipated for next generation's energy supplying system, and we can predict the PHEV will enlarge the market share in the next few years to reduce not only the air pollution in the metropolis but the fuel-expenses of commuters. This paper presents simulation results about the strategy of smart charging system for PHEV in the residential house which has 1 kW PEMFC cogeneration system. The smart charging system has a function of recommending the best time to charge the battery of PHEV by the lowest energy cost. The simulated energy cost for charging the battery based on the electricity demand data pattern in the house. The house which floor area is $132\;m^2$ (40 pyeong.). In these conditions, the annual gasoline, electricity, and total energy cost to fuel the PHEV versus Conventional Vehicle (CV) have been simulated in terms of cars' average life span in Korea.

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The Effect of Doenjang (Korean Soy Paste) on the Liver Enzyme Activities of the Sarcoma-180 Cell Transplanted Mice

  • Kim, Moon-Kyung;Moon, Suk-Hee;Park, Jong-Won;Park, Kun-Young
    • Preventive Nutrition and Food Science
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    • v.4 no.4
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    • pp.260-264
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    • 1999
  • Korean traditional fermented soy paste (doenjang) prolonged the life span of Balb/c mice injected with the sarcoma-180 cells. The activities of liver enzymes, such as xanthine oxidase, aminopyrine N-demethylase, aniline hydroxylase, ${\gamma}$-glutamylcysteine synthetase, glutathione reductase and glutathione S-transferase (GST), and the contents of lipid peroxide and glutathione were determined from the sarcoma-180 cell injected mice that were treated with methanol extracts from doenjang, miso and soybean. The content of lipid peroxide and the activity of xanthine oxidase in the liver of Balb/c mice which were increased by the transplantation of the sarcoma-180 cells were decreased by treatment with the methanol extract from doenjang. But the activities of aminopyrine N-dementhylase and aniline hydroxylase were not affected by the treatment of methanol extracts from doenjang to the mice injected with the sarcoma-180 cells. The content of glutathione, the activities of glutamylcysteine synthetase, glutathione reductase and glutathione S-transferase decreased by the injection of the sarcoma-180 were recovered considerably by the treatment of the methanol extract from doenjang.

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Study on the Renal Anemia - Experimental Study in Acute Renal Anemia - (신성빈혈(腎性貧血)에 관(關)한 연구(硏究) - 급성신성빈혈(急性腎性貧血)의 실험적(實驗的) 고찰(考察) -)

  • Yoon, Zo-Eun
    • The Korean Journal of Nuclear Medicine
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    • v.3 no.2
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    • pp.1-16
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    • 1969
  • The double tracer study on erythrokinetics was carried out experimentally with radioactive iron ($^{59}Fe$) and chromium ($^{51}Cr$) in rabbits. The 0.1% canthalidin solution and 1% pot. perchlomate solution was given subcutaneously to 20 rabbits respectively. 3 and 6 days after injection, the blood chemistry, urine examination, ferrokinetics and apparent half survival time of RBC were ($^{51}Cr\;T\frac{1}{2}$)determined. Following were the results: 1) Red blood cell hematocrit and hemoglobin values were moderately reduced and B.U.N. and serum creatinine values were slight]y inercased in the canthalidin group, while B.U.N. and serum creatinine values were within normal limits in the pot. perchlomate group. Reticulocyte values were slight]y increased in the canthalidin group, while was normal range in the pot. perchlomate group. 2) Blood chemistry finding was not significant statistically in both experimental groups, but serum iron value was moderately reduced in both group. 3) Plasma volume was unchanged in both group, but red cell volume and whole blood volume were slightly reduced in both groups. 4) Results of ferrokinetics were as follows: i) The plasma iron disappearance rate was delayed in both groups. Plasma iron turnover rate, red cell iron utilization and red cell iron turnover rate were decreased in both groups, and then red cell iron turnover rate was more decreased than plasma iron turnover rate in both groups. Circulating red cell iron was slight]y increased in canthalidin group and red cell iron concentration was within normal range in both groups. ii) P.I.T.R.-R.C.I.T. value was moderately increased in the canthalidin group and slightly increased in the pot. perchlomate group. Reticulocyte index, red cell iron turnover index, plasma iron turnover index and effective erythropoiesis index were whole]y reduced in both groups. iii) The red cell life span was slightly shortened in the canthalidin group while was within normal range in pot. perchlomate group. The pathologic finding of renal biopsy of the canthalidin group shows a selective damage in glomerulus, while shows almost normal range or slight damage in tubules. And that of the pot. perchlomate group shows a selective damage in tubules with slight damage of glomerulus.

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Pre-Natal Epigenetic Influences on Acute and Chronic Diseases Later in Life, such as Cancer: Global Health Crises Resulting from a Collision of Biological and Cultural Evolution

  • Trosko, James E.
    • Preventive Nutrition and Food Science
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    • v.16 no.4
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    • pp.394-407
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    • 2011
  • Better understanding of the complex factors leading to human diseases will be necessary for both long term prevention and for managing short and long-term health problems. The underlying causes, leading to a global health crisis in both acute and chronic diseases, include finite global health care resources for sustained healthy human survival, the population explosion, increased environmental pollution, decreased clean air, water, food distribution, diminishing opportunities for human self-esteem, increased median life span, and the interconnection of infectious and chronic diseases. The transition of our pre-human nutritional requirements for survival to our current culturally-shaped diet has created a biologically-mismatched human dietary experience. While individual genetic, gender, and developmental stage factors contribute to human diseases, various environmental and culturally-determined factors are now contributing to both acute and chronic diseases. The transition from the hunter-gatherer to an agricultural-dependent human being has brought about a global crisis in human health. Initially, early humans ate seasonally-dependent and calorically-restricted foods, during the day, in a "feast or famine" manner. Today, modern humans eat diets of caloric abundance, at all times of the day, with foods of all seasons and from all parts of the world, that have been processed and which have been contaminated by all kinds of factors. No longer can one view, as distinct, infectious agent-related human acute diseases from chronic diseases. Moreover, while dietary and environmental chemicals could, in principle, cause disease pathogenesis by mutagenic and cytotoxic mechanisms, the primary cause is via "epigenetic", or altered gene expression, modifications in the three types of cells (e.g., adult stem; progenitor and terminally-differentiated cells of each organ) during all stages of human development. Even more significantly, alteration in the quantity of adult stem cells during early development by epigenetic chemicals could either increase or decrease the risk to various stem cell-based diseases, such as cancer, later in life. A new concept, the Barker hypothesis, has emerged that indicates pre-natal maternal dietary exposures can now affect diseases later in life. Examples from the studies of the atomic bomb survivors should illustrate this insight.

Expression of Fas and TNFR1 in the Luteal Cell Types Isolated from the Ovarian Corpus Luteum

  • Kim, Minseong;Lee, Sang-Hee;Lee, Seunghyung;Kim, Gur-Yoo
    • Biomedical Science Letters
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    • v.25 no.1
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    • pp.107-112
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    • 2019
  • The corpus luteum (CL) is composed to various cells, such as luteal steroidogenic cells (LSCs), luteal thecal steroidogenic cells (LTCs), luteal endothelial cells (LECs), fibroblast, immune cells and blood cells. The life span of CL is controlled by proliferation and apoptosis of luteal cells. Therefore, this study investigated apoptotic factors in luteal cells derived from bovine CL. The CL tissues were collected from bovine ovaries and luteal cells were isolated from middle phase CL. Then, LTCs and LECs were separated according to cellular morphology from LSCs. The expression of Bax, Bcl-2, Fas and tumor necrosis factor 1 receptor (TNF1R) mRNA and protein were analyzed using quantitative RT-PCR and western blot. Results show that, Bax and TNFR1 mRNA expression were significantly increased at late group than early and middle groups, otherwise Bcl-2 were significantly decreased at late group than early group (P<0.05). Fas mRNA expression were significantly decreased in middle group compared to early and late groups (P<0.05). In addition, Bax and Bcl-2 mRNA in LTCs was lower than LSCs, Fas mRNA was higher than LSCs. The Bcl-2 protein expression was lower at LTCs than LSCs, especially Fas protein in LTCs was significantly lower than LSCs and LECs (P<0.05). Otherwise, TNFR1 protein of LTCs were similar with LSCs but higher compared with LECs. In conclusion, we suggest that the results may help understanding of apoptosis ability in luteal cells according to cell type during CL regression of estrous cycle.

Antitumor and antioxidant activities of Bryonia laciniosa against Ehrlich's Ascites Carcinoma bearing Swiss albino mice

  • Sivakumar, T;Kumar, R Sambath;Perumal, P;Vamsi, MLM;Sivakumar, P;Kanagasabai, R;Baskaran, MV;Karki, Subhas S;Mazumder, UK;Gupta, M
    • Advances in Traditional Medicine
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    • v.5 no.4
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    • pp.322-330
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    • 2005
  • The plant Bryonia laciniosa (Family: Cucurbitaceae) has been indicated for the treatment of various diseases one among which is cancer. The purpose of this study was investigating experimentally the possible anti-tumor effect and antioxidant role of Bryonia laciniosa leaves in animal model. The methanol extract of Bryonia laciniosa (MEBL) administered at the doses of 62.5, 125 and 250 mg/kg in mice for 14 days after 24 h of tumor inoculation. The effect of MEBL on the growth of transplantable murine tumor, life span of EAC bearing mice, hematological profile and liver biochemical parameters (lipid peroxidation, antioxidant enzymes) were estimated. Treatment with MEBL decreased the tumor volume and viable cell count thereby increasing the life span of EAC bearing mice and brought back the hematological parameter more or less normal level. The effect of MEBL also decreases the levels of lipid peroxidation and increased the levels of glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT). The present work indicates that the methanol extract of Bryonia laciniosa exhibited significant antitumor and antioxidant activity in vivo.

Effects of Korean ginseng berry on skin antipigmentation and antiaging via FoxO3a activation

  • Kim, Juewon;Cho, Si Young;Kim, Su Hwan;Cho, Donghyun;Kim, Sunmi;Park, Chan-Woong;Shimizu, Takahiko;Cho, Jae Youl;Seo, Dae Bang;Shin, Song Seok
    • Journal of Ginseng Research
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    • v.41 no.3
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    • pp.277-283
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    • 2017
  • Background: The ginseng berry has various bioactivities, including antidiabetic, anticancer, antiinflammatory, and antioxidative properties. Moreover, we have revealed that the active antiaging component of the ginseng berry, syringaresinol, has the ability to stimulate longevity via gene activation. Despite the many known beneficial effects of ginseng, its effects on skin aging are poorly understood. In this study, we investigated the effects of ginseng and the ginseng berry on one of the skin aging processes, melanogenesis, and age-related pigment lipofuscin accumulation, to elucidate the mechanism of action with respect to antiaging. Methods: The human melanoma MNT1 cell line was treated with ginseng root extract, ginseng berry extract, or syringaresinol. Then, the cells were analyzed using a melanin assay, and the tyrosinase activity was estimated. The Caenorhabditis elegans wild type N2 strain was used for the life span assay to analyze the antiaging effects of the samples. A lipofuscin fluorescence assay was performed during 10 passages with the syringaresinol treatment. Results: A 7-d treatment with ginseng berry extract reduced melanin accumulation and tyrosinase activity more than ginseng root extract. These results may be due to the active compound of the ginseng berry, syringaresinol. The antimelanogenic activity was strongly coordinated with the activation of the longevity gene foxo3a. Moreover, the ginseng berry extract had more potent antiaging effects, caused a life span extension, and reduced lipofuscin accumulation. Conclusion: Taken together, our results suggest that these antimelanogenic effects and antiaging effects of ginseng berry mediate the activation of antioxidation-FoxO3a signaling.

Anticancer Effects of Egg White Combined-Chalcanthite on NCI-H460 Tumor Regression Model (NCI-H460 폐암 유발 누드마우스 모형을 이용한 난담반의 항암 효과 연구)

  • Choi, Eun-A;Kim, Jung-Keun;Kim, Kyung-Soon;Choi, Jung-Eun;Cho, Chong-Kwan;Lee, Yeon-Weol;Yoo, Hwa-Seung
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.24 no.2
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    • pp.272-277
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    • 2010
  • This experimental study was performed to investigate the antitumor effect of Egg white combined-Chalcanthite (InSan 4, IS4) in xenografted nude mice with NCI-H460 human lung cancer cell. We cultured NCI-H460 cell lines and xenografted them on nude mice. These mice were divided into 3 groups; group with dose of 45 mg/kg IS4 orally, group with dose of 90 mg/kg IS4 orally, and the control group. They had been raised and treated for 28 days. We checked their body weight, tumor weight and volume twice a week, and their absolute organ weight, microhistological observation and biochemical blood analysis at the final day by sacrificing them. We also calculated their tumor inhibition rate (IR), mean survival time and percent increase in life span (% ILS). In this study, we observed that all of the IS4 treated mice have tumor regression, dosage-dependently, compared to the control group. Tumor weight and volume of high dose treated mice were smallest. IR increased in IS4 in a dose-dependent manner. Mean survival time and percent increase in life span (% ILS) in high-dose IS4 treatment group were the highest of the three groups. There was no significant difference in biochemical blood analysis, alanine phopsphatase (ALP), Calcium, creatinine (CRE), alanine transferase (ALT), and aspartate transaminase (AST) levels. The urea nitrogen (UN) level results significantly decreased by IS4 45 and 90 mg/kg (IS4 45 mg/kg, IS4 90 mg/kg, p<0.01). IS4 may have potential anti-tumor effect in a solid tumor induced by NCI-H460 without remarkable side effects.