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321.
Jong Seok Lee Jae Wan Wee Hye Young Lee Hyo Sil An Eock Kee Hong 《Biotechnology and Bioprocess Engineering》2010,15(3):453-459
Hericium erinaceus is a well known edible and medicinal mushroom used in East-Asia. Recently, H. erinaceus has attracted a lot of attention owing to its antitumor, immuno-modulatory, and cytotoxic effect. It has been postulated that the fruiting body of H. erinaceus contains a polysaccharide that is similar to β-D-glucan, which is known to have antitumor activity against Sarcoma 180. However, optimized liquid culture conditions for enhanced polysaccharide productivity have yet to be developed, which is a necessary step for industrial applications. Therefore, the aim of this study was to determine the optimal liquid culture conditions for maximum polysaccharide production. In shake flask cultures, the optimal concentration of ascorbic acid was found to be 2.0 g/L, which prevented the broth from changing color from yellow to black. The optimal culture conditions were determined to be 23°C, 200 rpm, and a 10% inoculum size, at an uncontrolled initial pH. In addition, the modified medium contained 20 g/L glucose, 10 g/L yeast extract, and 2.0 g/L ascorbic acid. The maximum mycelial biomass and exo-polysaccharide (EPS) production in the modified medium containing uracil was 13.43 and 1.26 g/L, respectively. 相似文献
322.
Hui‐Hsu Gavin Tsai Jian‐Bin Lee Sheng‐Shiuan Tseng Xiao‐An Pan Yuan‐Ci Shih 《Proteins》2010,78(8):1909-1925
The mechanisms of interfacial folding and membrane insertion of the Alzheimer's amyloid‐β fragment Aβ(25–35) and its less toxic mutant, N27A‐Aβ(25–35) and more toxic mutant, M35A‐Aβ(25–35), are investigated using replica–exchange molecular dynamics in an implicit water‐membrane environment. This study simulates the processes of interfacial folding and membrane insertion in a spontaneous fashion to identify their general mechanisms. Aβ(25–35) and N27A‐Aβ(25–35) peptides share similar mechanisms: the peptides are first located in the membrane hydrophilic region where their C‐terminal residues form helical structures. The peptides attempt to insert themselves into the membrane hydrophobic region using the C‐terminal or central hydrophobic residues. A small portion of peptides can successfully enter the membrane's hydrophobic core, led by their C‐terminal residues, through the formation of continuous helical structures. No detectable amount of M35A‐Aβ(25–35) peptides appeared to enter the membrane's hydrophobic core. The three studied peptides share a similar helical structure for their C‐terminal five residues, and these residues mainly buried within the membrane's hydrophobic region. In contrast, their N‐terminal properties are markedly different. With respect to the Aβ(25–35), the N27A‐Aβ(25–35) forms a more structured helix and is buried deeper within the membrane, which may result in a lower degree of aggregation and a lower neurotoxicity; in contrast, the less structured and more water‐exposed M35A‐Aβ(25–35) is prone to aggregation and has a higher neurotoxicity. Understanding the mechanisms of Aβ peptide interfacial folding and membrane insertion will provide new insights into the mechanisms of neurodegradation and may give structure‐based clues for rational drug design preventing amyloid associated diseases. Proteins 2010. © 2010 Wiley‐Liss, Inc. 相似文献
323.
Jae J. Song Miroslaw Jerzy Szczepanski So Young Kim Joo-Hang Kim Jee Young An Yong Tae Kwon Marco A. Alcala David L. Bartlett Yong J. Lee 《Cellular signalling》2010,22(3):553-563
We previously reported two modes of development of acquired TRAIL resistance: early phase and late phase [1]. In these studies, we observed that greater Akt activity and the expression of Bcl-xL were related mainly to the late phase of acquired TRAIL resistance.Recently we became aware of a possible mechanism of early phase TRAIL resistance development through internalization and degradation of TRAIL receptors (DR4 and DR5). Our current studies demonstrate that TRAIL receptors rapidly diminish at the membrane as well as the cytoplasm within 4 h after TRAIL exposure, but recover completely after one or two days. Our studies also reveal that Cbl, a ubiquitously expressed cytoplasmic adaptor protein, is responsible for the rapid degradation of TRAIL receptors; Cbl binds to them and induces monoubiquitination of these receptors concurrent with their degeneration soon after TRAIL exposure, creating the early phase of acquired TRAIL resistance. 相似文献
324.
An Vercalsteren Carolin Spirinckx Theo Geerken 《The International Journal of Life Cycle Assessment》2010,15(2):221-230
Background, aim, and scope
At the request of the Public Waste Agency for the Flemish Region, the Flemish Institute for Technological Research performed a life cycle assessment (LCA), according to the International Organization for Standardization (ISO) 14040 procedures (ISO 1997, 1998, 2000, and ISO 2006), followed by an eco-efficiency analysis of four alternative types of drinking cups for use at public events. The results of the LCA study served as input for the eco-efficiency analysis in which the costs related to the four cup systems were studied and combined with the environmental impacts. The objective of this study was to gain insight into the current environmental impacts and costs related to existing systems for drinking cups at public events in Flanders (Belgium) in order to outline a well-founded policy with regard to this subject. Since the results of this comparative study are publicly available, a critical review was performed according to ISO 14040 (review by interested parties, using a review panel) after each stage (goal and scope, data inventory, impact analysis/interpretation, eco-efficiency analysis) during the study. 相似文献325.
Osthole, an ingredient of Traditional Chinese Medicine (TCM) from natural product Cnidium monnieri (L.) Cusson, was used as a lead compound for structural modification. A series of osthole derivatives bearing aryl substituents at 3-position of coumarin, has been prepared and evaluated for their growth inhibitory activity against human breast cancer cell lines MCF-7 and MDA-MB-231. Interestingly, some derivatives exhibited good inhibition, among them compound 8e was found to be the most potent compound with IC(50) values of 0.24 μM, 0.31 μM against MCF-7 and MDA-MB-231, respectively, which was improved more than 100-folds compared with its parent compound osthole. 相似文献
326.
Jacob A. Kaizerman Wade Aaron Songzhu An Richard Austin Matt Brown Angela Chong Tom Huang Randall Hungate Ben Jiang Michael G. Johnson Gary Lee Brian S. Lucas Jessica Orf Minqing Rong Maria M. Toteva Dineli Wickramasinghe Guifen Xu Qiuping Ye Wendy Zhong Dustin L. McMinn 《Bioorganic & medicinal chemistry letters》2010,20(15):4607-4610
Pyridopyridazine antagonists of the hedgehog signaling pathway are described. Designed to optimize our previously described phthalazine smoothened antagonists, a representative compound eliminates a PXR liability while retaining potency and in vitro metabolic stability. Moreover, the compound has improved efficacy in a hedgehog/smoothened signaling mouse pharmacodynamic model. 相似文献
327.
Xiang-Yang Ye Stephanie Chen Hao Zhang Kenneth T. Locke Kevin O’Malley Litao Zhang Raijit Srivastava Bowman Miao Daniel Meyers Hossain Monshizadegan Debra Search Denise Grimm Rongan Zhang Jonathan Lippy Celeste Twamley Jodi K. Muckelbauer Chiehying Chang Yongmi An Vinayak Hosagrahara Lisa Zhang Joseph A. Tino 《Bioorganic & medicinal chemistry letters》2010,20(9):2933-2937
The synthesis and follow-up SAR studies of our development candidate 1 by incorporating 2-aryl-4-oxazolylmethoxy and 2-aryl-4-thiazolylmethoxy moieties into the oxybenzylglycine framework of the PPARα/γ dual agonist muraglitazar is described. SAR studies indicate that different substituents on the aryloxazole/thiazole moieties as well as the choice of carbamate substituent on the glycine moiety can significantly modulate the selectivity of PPARα versus PPARγ. Potent, highly selective PPARα activators 2a and 2l, as well as PPARα activators with significant PPARγ activity, such as 2s, were identified. The in vivo pharmacology of these compounds in preclinical animal models as well as their ADME profiles are discussed. 相似文献
328.
Cancer is characterized by disturbed homeostasis of self-renewing cell populations, and their ability to seed and grow in multiple microenvironments. This overarching cellular property of metastatic cancer emerges from the contentious cancer stem cell hypothesis that underpins the more generic hallmarks of cancer (Hanahan and Weinberg, 2000) and its subsequent add-ons. An additional characteristic, metabolic flexibility, is related to concepts developed by Warburg and to subsequent work by mid 20th century biochemists who elucidated the bioenergetic workings of mitochondria. Metabolic flexibility may circumvent limitations inherent in the increasingly popular but erroneous view that aerobic glycolysis is a universal property of cancer cells. Cancer research in the second half of the 20th century was largely the domain of geneticists and molecular biologists using reductionist approaches. Integrated approaches that address cancer cell hierarchy and complexity, and how cancer cells adapt their metabolism according to their changing environment are now beginning to emerge, and these approaches promise to address the poor mortality statistics of metastatic cancer. 相似文献
329.
OsZIP5 is a plasma membrane zinc transporter in rice 总被引:1,自引:0,他引:1
Sichul Lee Hee Joong Jeong Sun A. Kim Joohyun Lee Mary Lou Guerinot Gynheung An 《Plant molecular biology》2010,73(4-5):507-517
Zinc is essential for normal plant growth and development. To understand its transport in rice, we characterized OsZIP5, which is inducible under Zn deficiency. OsZIP5 complemented the growth defect of a yeast Zn-uptake mutant, indicating that OsZIP5 is a Zn transporter. The OsZIP5-GFP fusion protein was localized to the plasma membrane. Transgenic plants overexpressing the gene grew less well. Overexpression of the gene decreased the Zn concentration in shoots, but caused it to rise in the roots. Knockout plants showed no visible phenotypic changes under either normal or deficient conditions. However, they were tolerant to excess Zn and contained less Zn. In contrast, overexpressing transgenics were sensitive to excess Zn. These results indicate that OsZIP5 plays a role in Zn distribution within rice. 相似文献
330.