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71.
72.
Han-En Tsai Jian-Ching Wu Mei-Lang Kung Li-Feng Liu Lai-Hsin Kuo Hsiao-Mei Kuo San-Cher Chen Elsa C. Chan Chieh-Shan Wu Ming-Hong Tai Guei-Sheung Liu 《PloS one》2013,8(3)
Cutaneous malignant melanoma is the fastest increasing malignancy in humans. Hepatoma-derived growth factor (HDGF) is a novel growth factor identified from human hepatoma cell line. HDGF overexpression is correlated with poor prognosis in various types of cancer including melanoma. However, the underlying mechanism of HDGF overexpression in developing melanoma remains unclear. In this study, human melanoma cell lines (A375, A2058, MEL-RM and MM200) showed higher levels of HDGF gene expression, whereas human epidermal melanocytes (HEMn) expressed less. Exogenous application of HDGF stimulated colony formation and invasion of human melanoma cells. Moreover, HDGF overexpression stimulated the degree of invasion and colony formation of B16–F10 melanoma cells whereas HDGF knockdown exerted opposite effects in vitro. To evaluate the effects of HDGF on tumour growth and metastasis in vivo, syngeneic mouse melanoma and metastatic melanoma models were performed by manipulating the gene expression of HDGF in melanoma cells. It was found that mice injected with HDGF-overexpressing melanoma cells had greater tumour growth and higher metastatic capability. In contrast, mice implanted with HDGF-depleted melanoma cells exhibited reduced tumor burden and lung metastasis. Histological analysis of excised tumors revealed higher degree of cell proliferation and neovascularization in HDGF-overexpressing melanoma. The present study provides evidence that HDGF promotes tumor progression of melanoma and targeting HDGF may constitute a novel strategy for the treatment of melanoma. 相似文献
73.
Rajkumar Dorajoo Ruoying Li Mohammad Kamran Ikram Jianjun Liu Philippe Froguel Jeannette Lee Xueling Sim Rick Twee-Hee Ong Wan Ting Tay Chen Peng Terri L. Young Alexandra I. F. Blakemore Ching Yu Cheng Tin Aung Paul Mitchell Jie Jin Wang Caroline C. Klaver Eric Boerwinkle Ronald Klein David S. Siscovick Richard A. Jensen Vilmundur Gudnason Albert Vernon Smith Yik Ying Teo Tien Yin Wong E-Shyong Tai Chew-Kiat Heng Yechiel Friedlander 《PloS one》2013,8(7)
Introduction
C-reactive protein (CRP) levels are associated with cardiovascular disease and systemic inflammation. We assessed whether CRP-associated loci were associated with serum CRP and retinal markers of microvascular disease, in Asian populations.Methods
Genome-wide association analysis (GWAS) for serum CRP was performed in East-Asian Chinese (N = 2,434) and Malays (N = 2,542) and South-Asian Indians (N = 2,538) from Singapore. Leveraging on GWAS data, we assessed, in silico, association levels among the Singaporean datasets for 22 recently identified CRP-associated loci. At loci where directional inconsistencies were observed, quantification of inter-ethnic linkage disequilibrium (LD) difference was determined. Next, we assessed association for a variant at CRP and retinal vessel traits [central retinal artery equivalent (CRAE) and central retinal vein equivalent (CRVE)] in a total of 24,132 subjects of East-Asian, South-Asian and European ancestry.Results
Serum CRP was associated with SNPs in/near APOE, CRP, HNF1A and LEPR (p-values ≤4.7×10−8) after meta-analysis of Singaporean populations. Using a candidate-SNP approach, we further replicated SNPs at 4 additional loci that had been recently identified to be associated with serum CRP (IL6R, GCKR, IL6 and IL1F10) (p-values ≤0.009), in the Singaporean datasets. SNPs from these 8 loci explained 4.05% of variance in serum CRP. Two SNPs (rs2847281 and rs6901250) were detected to be significant (p-value ≤0.036) but with opposite effect directions in the Singaporean populations as compared to original European studies. At these loci we did not detect significant inter-population LD differences. We further did not observe a significant association between CRP variant and CRVE or CRAE levels after meta-analysis of all Singaporean and European datasets (p-value >0.058).Conclusions
Common variants associated with serum CRP, first detected in primarily European studies, are also associated with CRP levels in East-Asian and South-Asian populations. We did not find a causal link between CRP and retinal measures of microvascular disease. 相似文献74.
75.
In vitro pattern classification has been highlighted as an important future application of DNA computing. Previous work has demonstrated the feasibility of linear classifiers using DNA-based molecular computing. However, complex tasks require non-linear classification capability. Here we design a molecular beacon that can interact with multiple targets and experimentally shows that its fluorescent signals form a complex radial-basis function, enabling it to be used as a building block for non-linear molecular classification in vitro. The proposed method was successfully applied to solving artificial and real-world classification problems: XOR and microRNA expression patterns. 相似文献
76.
Yung‐Lin Hsieh Hong‐Yi Kuo Che‐Chang Chang Mandar T Naik Pei‐Hsin Liao Chun‐Chen Ho Tien‐Chi Huang Jen‐Chong Jeng Pang‐Hung Hsu Ming‐Daw Tsai Tai‐Huang Huang Hsiu‐Ming Shih 《The EMBO journal》2013,32(6):791-804
While numerous small ubiquitin‐like modifier (SUMO) conjugated substrates have been identified, very little is known about the cellular signalling mechanisms that differentially regulate substrate sumoylation. Here, we show that acetylation of SUMO E2 conjugase Ubc9 selectively downregulates the sumoylation of substrates with negatively charged amino acid‐dependent sumoylation motif (NDSM) consisting of clustered acidic residues located downstream from the core ψ‐K‐X‐E/D consensus motif, such as CBP and Elk‐1, but not substrates with core ψ‐K‐X‐E/D motif alone or SUMO‐interacting motif. Ubc9 is acetylated at residue K65 and K65 acetylation attenuates Ubc9 binding to NDSM substrates, causing a reduction in NDSM substrate sumoylation. Furthermore, Ubc9 K65 acetylation can be downregulated by hypoxia via SIRT1, and is correlated with hypoxia‐elicited modulation of sumoylation and target gene expression of CBP and Elk‐1 and cell survival. Our data suggest that Ubc9 acetylation/deacetylation serves as a dynamic switch for NDSM substrate sumoylation and we report a previously undescribed SIRT1/Ubc9 regulatory axis in the modulation of protein sumoylation and the hypoxia response. 相似文献
77.
Chitin, after cellulose, is the second most abundant natural polymer. With a 200-year history of scientific research, chitin is beginning to see fruitful application in the fields of stem cell and tissue engineering. To date, however, research in chitin as a biomaterial appears to lag far behind that of its close relative, chitosan, due to the perceived difficulty in processing chitin. This review presents methods to improve the processability of chitin, and goes on further to discuss the unique physicochemical and biological characteristics of chitin that favor it as a biomaterial for regenerative medicine applications. Examples of the latter are presented, with special attention on the qualities of chitin that make it inherently suitable as scaffolds and matrices for tissue engineering, stem cell propagation and differentiation. 相似文献
78.
Fuju Tai Qi Wang Zuli Yuan Zhiheng Yuan Huiyun Li Wei Wang 《Acta Physiologiae Plantarum》2013,35(5):1555-1564
ABA, H2O2 and Ca2+ play critical roles as signals in the adaptive responses of plants to water and other stresses. They accumulate in plant cells under water and other stresses and induce changes in stress-related gene expressions. CIPKs, protein kinases associated with a calcineurin B-like calcium sensor, play a role in the regulation of stress gene expression in plants. However, it is still unclear whether ABA and H2O2 are key inducers that regulate the changes in CIPK expressions under water stress. In this study, five stress-inducible CIPKs in maize were retrieved from Database. They were designated as ZmCIPK1, 3, 8, 17 and 18, based on their homologies with known CIPK sequences. The expressions of the five ZmCIPKs in maize leaves and roots were analyzed and found to be regulated by PEG, CaCl2, ABA and H2O2 to different extents. Moreover, the effect of ABA and H2O2 on the expressions of ZmCIPKs under water stress was in an organ-dependent manner. 相似文献
79.
Hui-Chuan Yu Chen-Si Lin Wei-Tien Tai Chun-Yu Liu Chung-Wai Shiau Kuen-Feng Chen 《The Journal of biological chemistry》2013,288(25):18249-18259
Hepatocellular carcinoma (HCC) is the most common liver cancer and the third-leading cause of cancer death worldwide. Nilotinib is an orally available receptor tyrosine kinase inhibitor approved for chronic myelogenous leukemia. This study investigated the effect of nilotinib on HCC. Nilotinib did not induce cellular apoptosis. Instead, staining with acridine orange and microtubule-associated protein 1 light chain 3 revealed that nilotinib induced autophagy in a dose- and time-dependent manner in HCC cell lines, including PLC5, Huh-7, and Hep3B. Moreover, nilotinib up-regulated the phosphryaltion of AMP-activated kinase (AMPK) and protein phosphatase PP2A inactivation were detected after nilotinib treatment. Up-regulating PP2A activity suppressed nilotinib-induced AMPK phosphorylation and autophagy, suggesting that PP2A mediates the effect of nilotinib on AMPK phosphorylation and autophagy. Our data indicate that nilotinib-induced AMPK activation is mediated by PP2A, and AMPK activation and subsequent autophagy might be a major mechanism of action of nilotinib. Growth of PLC5 tumor xenografts in BALB/c nude mice was inhibited by daily oral treatment with nilotinib. Western blot analysis showed both increased phospho-AMPK expression and decreased PP2A activity in vivo. Together, our results reveal that nilotinib induces autophagy, but not apoptosis in HCC, and that the autophagy-inducing activity is associated with PP2A-regulated AMPK phosphorylation. 相似文献
80.
Jürgen Lange Motofumi Tai 《Der Zoologische Garten (in deutscher Sprache / in German)》2013,82(3-4):137-166
In the year 2013, the authors, who had already visited some Japanese aquariums and zoos in 2012 (Lange & Tai, 2012), revisited several Japanese aquariums and zoos. They were accompanied by two colleagues from Basle Zoo and the Monterey Bay Aquarium, who joined the tour.Their goals of the tour were focused on new innovative husbandry methods, on new aquarium buildings and new zoo enclosures as well as on rare Japanese endemic animals, which are never or seldom seen outside of Japan.The perfect new aquariums in Kyoto and Kitami City (Hokkaido), but also the very specialized aquariums like the Kamo Aquarium (for jellyfish) in Yamagata, the Chitose Salmon Aquarium (for salmons), the Otaru Aquarium (for sea mammals) and the Umi Kirara Kujukushima Aquarium (for the fauna of the Kujukushima island National Park) have been destinations for this trip. Besides the aquariums also the Asahiyama Zoo (new enclosures for endemic animals of Hokkaido), Kobe Oji Zoo, Kushiro Zoo (many endemic Hokkaido species), Nagasaki Bio Park, Sapporo Maruyama Zoo (new area for South East Asian animals) and the Sasebo Zoological & Botanical Garden were visited.During this tour it was obvious that neither the colleagues in Japan nor the staff in the zoos outside of Japan know sufficient enough about the conception and the husbandry methods in the different institutions in this part of the world. Therefore it is recommendable to organize such tours often for more people, thus both sides can benefit and learn from each other. This again will influence to help to keep the animals better, to attract more visitors in order to inspire them for the conservation of nature and environment. 相似文献