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81.
82.
Bit Na Seo Jung Min Ryu Seung Pil Yun Ji Hoon Jeon Su Shin Park Keon Bong Oh Jin-Ki Park Ho Jae Han 《Apoptosis : an international journal on programmed cell death》2013,18(7):811-824
Delphinidin, gallic acid, betulinic acid, and ursolic acid, which are bio-active ingredients in a variety of fruits, vegetables, and herbs, have potent antioxidant activity and various biological activities. However, it is not clear whether these bio-active ingredients can significantly contribute to the protection of embryonic stem (ES) cells from hypoxia-induced apoptosis. In the present study, hypoxia-induced ES cells apoptosis with time, which were abrogated by pretreatment with all ingredients. Hypoxia-induced ROS generation was blocked by pretreatment with all ingredients in a dose-dependent manner, with the maximum ROS scavenging effect observed for delphinidin. Hypoxia increased phosphorylation of JNK and NF-κB were blocked by pretreatment of delphinidin as well as NAC. Hypoxia decreased phosphorylation of Aktthr308 and ser473; these decreases were reversed by pretreatment with delphinidin or NAC. However, Akt inhibition did not affect NF-κB phosphorylation. Delphinidin attenuated the hypoxia-induced increase in Bax, cleaved caspase-9, cleaved caspase-3, and decrease in Bcl-2, which were diminished by pretreatment of Akt inhibitor. Hypoxia induced Bax translocation from the cytosol to mitochondria. Furthermore, hypoxia induced mitochondria membrane potential loss and cytochrome c release in cytosol, which were blocked by delphinidin pretreatment. Hypoxia induced cleavage of procaspase-9 and procaspase-3 which were blocked by delphinidin or SP600125, but Akt inhibitor abolished the protection effect of delphinidin. Moreover, inhibition of JNK and NF-κB abolished hypoxia-induced ES cell apoptosis and inhibition of Akt attenuated delphinidin-induced blockage of apoptosis. The results indicate that delphinidin can prevent hypoxia-induced apoptosis of ES cells through the inhibition of JNK and NF-κB phosphorylation, and restoration of Akt phosphorylation. 相似文献
83.
Yoon Sang Kim Junho Ko Dong-Kwang Shin Chul-Hwan Kim Chul-Won Park 《Cluster computing》2013,16(2):209-217
There have been recent research activities on GPS-based FNET to prevent wide-area blackouts by monitoring frequency deviation. This paper introduces a system for monitoring regional frequencies in power grid developed as an advanced research project for intelligent wide-area protective relaying in South Korea. The system is implemented by modeling an actual 345 kV transmission system of South Korea using EMTP-RV and by measuring voltages and currents at five regions. The frequencies are estimated using our previous proposed method, a frequency estimation algorithm with gain compensation. The monitoring system implemented is used to examine frequency propagation effects and various fault conditions. Simulation results showed that the proposed system could achieve good performance regarding the frequency monitoring under both steady states and dynamic fault conditions. 相似文献
84.
Jung-Hoon Kim Eun-Hye Shin Hak-Yong Lee Bong-Gun Lee Sang-Hoon Park Dae-In Moon Gyo-Chang Goo Dae-Young Kwon Hye-Jeong Yang Ok-Jin Kim Hong-Geun Oh 《Experimental Animals》2013,62(3):247-253
As malfunction/absence of immune cells causes a variety of immunosuppressive disorders
and chemical synthetic drugs for curing these diseases have many adverse effects, vigorous
studies are being conducted. The Acanthopanax family has been used as
traditional medicines for gastric ulcer, diabetes, etc. and culinary materials in
East-South Asia. In this study, the immunostimulating properties of A.
sessiliflorus were evaluated. A. sessiliflorus increased not
only the splenocyte number but also immune-related cytokines such as TNF-α. However, it
could not upregulate the expressions of IFN-γ and IL-2. A. sessiliflorus
increased the swimming time, and comparison of organ weights relative to body weights for
immune-related organs such as the spleen and thymus after a forced swim test showed that
it could recover the spleen and thymus weights. It also increased the expression of TNF-α
and slightly increased the concentration of IFN-γ but not IL-2. From the results, we
concluded that as A. sessiliflorus has not only a host defense effect but
also a stress-ameliorating property, further study it will be a promising material of
immunostimulating material. 相似文献
85.
Seung Mi Lee Jeong Woo Park Byoung Jae Kim Chan-Wook Park Joong Shin Park Jong Kwan Jun Bo Hyun Yoon 《PloS one》2013,8(12)
Background
The objective of this study was to determine whether acute histologic chorioamnionitis is associated with adverse neonatal outcomes in late preterm infants who were born after preterm PROM.Methodology/Principal Findings
The relationship between the presence of acute histologic chorioamnionitis and adverse neonatal outcome was examined in patients with preterm PROM who delivered singleton preterm newborns between 34 weeks and 36 6/7 weeks of gestation. Nonparametric statistics were used for data analysis. The frequency of acute histologic chorioamnionitis was 24% in patients with preterm PROM who delivered preterm newborns between 34 weeks and 36 6/7 weeks of gestation. Newborns born to mothers with histologic chorioamnionitis had significantly higher rates of adverse neonatal outcome (74% vs 51%; p<0.005) than those without histologic chorioamnionitis. This relationship remained significant after adjustment for gestational age at preterm PROM, gestational age at delivery, and exposure to antenatal corticosteroids.Conclusions/Significance
The presence of acute histologic chorioamnionitis is associated with adverse neonatal outcome in late preterm infants born to mothers with preterm PROM. 相似文献86.
87.
Pengcheng Bu Kai-Yuan Chen Joyce Huan Chen Lihua Wang Jewell Walters Yong Jun Shin Julian P. Goerger Jian Sun Mavee Witherspoon Nikolai Rakhilin Jiahe Li Herman Yang Jeff Milsom Sang Lee Warren Zipfel Moonsoo M. Jin Zeynep H. Gümüş Steven M. Lipkin Xiling Shen 《Cell Stem Cell》2013,12(5):602-615
Highlights? miR-34a regulates colon cancer stem cell asymmetric division ? miR-34a generates a sharp threshold response ? miR-34a converts Notch signaling into a toggle switch ? Binary Notch levels specify self-renewal versus differentiation 相似文献
88.
Byung-Im So Yi-Sun Song Cheng-Hu Fang Jun-Young Park Yonggu Lee Jeong Hun Shin Hyuck Kim Kyung-Soo Kim 《PloS one》2013,8(10)
Background
The protective effects of granulocyte colony-stimulating factor (G-CSF) have been demonstrated in a variety of renal disease models. However, the influence of G-CSF on diabetic nephropathy (DN) remains to be examined. In this study, we investigated the effect of G-CSF on DN and its possible mechanisms in a rat model.Methods
Otsuka Long-Evans Tokushima Fatty (OLETF) rats with early DN were administered G-CSF or saline intraperitoneally. Urine albumin creatinine ratio (UACR), creatinine clearance, mesangial matrix expansion, glomerular basement membrane (GBM) thickness, and podocyte foot process width (FPW) were measured. The levels of interleukin (IL)-1β, transforming growth factor (TGF)-β1, and type IV collagen genes expression in kidney tissue were also evaluated. To elucidate the mechanisms underlying G-CSF effects, we also assessed the expression of G-CSF receptor (G-CSFR) in glomeruli as well as mobilization of bone marrow (BM) cells to glomeruli using sex-mismatched BM transplantation.Results
After four weeks of treatment, UACR was lower in the G-CSF treatment group than in the saline group (p<0.05), as were mesangial matrix expansion, GBM thickness, and FPW (p<0.05). In addition, the expression of TGF-β1 and type IV collagen and IL-1β levels was lower in the G-CSF treatment group (p<0.05). G-CSFR was not present in glomerular cells, and G-CSF treatment increased the number of BM-derived cells in glomeruli (p<0.05).Conclusions
G-CSF can prevent the progression of DN in OLETF rats and its effects may be due to mobilization of BM cells rather than being a direct effect. 相似文献89.
Eunjung Lee Ki-Woong Jeong Areum Shin Bonghwan Jin Hum Nath Jnawali Bong-Hyun Jun Jee-Young Lee Yong-Seok Heo Yangmee Kim 《BMB reports》2013,46(12):594-599
The anti-inflammatory activity of eriodictyol and its mode of action were investigated. Eriodictyol suppressed tumor necrosis factor (mTNF)-α, inducible nitric oxide synthase (miNOS), interleukin (mIL)-6, macrophage inflammatory protein (mMIP)-1, and mMIP-2 cytokine release in LPS-stimulated macrophages. We found that the anti-inflammatory cascade of eriodictyol is mediated through the Toll-like Receptor (TLR)4/CD14, p38 mitogen-activated protein kinases (MAPK), extracellular-signalregulated kinase (ERK), Jun-N terminal kinase (JNK), and cyclooxygenase (COX)-2 pathway. Fluorescence quenching and saturation-transfer difference (STD) NMR experiments showed that eriodictyol exhibits good binding affinity to JNK, 8.79 × 105 M-1. Based on a docking study, we propose a model of eriodictyol and JNK binding, in which eriodictyol forms 3 hydrogen bonds with the side chains of Lys55, Met111, and Asp169 in JNK, and in which the hydroxyl groups of the B ring play key roles in binding interactions with JNK. Therefore, eriodictyol may be a potent anti-inflammatory inhibitor of JNK. [BMB Reports 2013; 46(12): 594-599] 相似文献
90.
Dong Hoon Shin Gyeong Im Yu Jae Seok Hwang Eun Soo Kim Jong Won Yun 《Proteomics》2013,13(15):2361-2374
In the present study, we screened proteomic and cytokine biomarkers between patients with adenomatous polyps and colorectal cancer (CRC) in order to improve our understanding of the molecular mechanisms behind turmorigenesis and tumor progression in CRC. To this end, we performed comparative proteomic analysis of plasma proteins using a combination of 2DE and MS as well as profiled differentially regulated cytokines and chemokines by multiplex bead analysis. Proteomic analysis identified 11 upregulated and 13 downregulated plasma proteins showing significantly different regulation patterns with diagnostic potential for predicting progression from adenoma to carcinoma. Some of these proteins have not previously been implicated in CRC, including upregulated leucine‐rich α‐2‐glycoprotein, hemoglobin subunit β, Ig α‐2 chain C region, and complement factor B as well as downregulated afamin, zinc‐α‐2‐glycoprotein, vitronectin, and α‐1‐antichymotrypsin. In addition, plasma levels of three cytokines/chemokines, including interleukin‐8, interferon gamma‐induced protein 10, and tumor necrosis factor α, were remarkably elevated in patients with CRC compared to those with adenomatous polyps. Although further clinical validation is required, these proteins and cytokines can be established as novel biomarkers for CRC and/or its progression from colon adenoma. 相似文献