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101.

Ganoderma spp. are medical mushrooms with various pharmacological compounds which are regarded as a nutraceutical for improving health and treating diseases. This review summarizes current progress in the studies of Gamoderma ranging from bioactive metabolites, bioactivities, production techniques to clinical trials. Traditionally, polysaccharides and ganoderic acids have been reported as the major bioactive metabolites of Ganoderma possessing anti-tumor and immunomodulation functions. Moreover, recent studies indicate that Gandoerma also exerts other bioactivities such as skin lighting, gut microbiota regulation, and anti-virus effects. However, since these medical fungi are rare in natural environment, and that the cost of cultivation of fruiting bodies is high, industrial submerged fermentation of Ganoderma mycelia promotes the development of Ganoderma by dint of an increase of biomass and bioactive metabolites used for further application. In addition, various strategies for production of different metabolites are well developed, such as gene regulation, bi-stage pH, and oxygen control. To date, Ganoderma not only has become one of the most popular nutraceuticals worldwide but also has been applied to clinical trials for advanced diseases such as breast and non-small-cell lung cancer.

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Sequence-specific protein-nucleic acid recognition is determined, in part, by hydrogen bonding interactions between amino acid side-chains and nucleotide bases. To examine the repertoire of possible interactions, we have calculated geometrically plausible arrangements in which amino acids hydrogen bond to unpaired bases, such as those found in RNA bulges and loops, or to the 53 possible RNA base-pairs. We find 32 possible interactions that involve two or more hydrogen bonds to the six unpaired bases (including protonated A and C), 17 of which have been observed. We find 186 "spanning" interactions to base-pairs in which the amino acid hydrogen bonds to both bases, in principle allowing particular base-pairs to be selectively targeted, and nine of these have been observed. Four calculated interactions span the Watson-Crick pairs and 15 span the G:U wobble pair, including two interesting arrangements with three hydrogen bonds to the Arg guanidinum group that have not yet been observed. The inherent donor-acceptor arrangements of the bases support many possible interactions to Asn (or Gln) and Ser (or Thr or Tyr), few interactions to Asp (or Glu) even though several already have been observed, and interactions to U (or T) only if the base is in an unpaired context, as also observed in several cases. This study highlights how complementary arrangements of donors and acceptors can contribute to base-specific recognition of RNA, predicts interactions not yet observed, and provides tools to analyze proposed contacts or design novel interactions.  相似文献   
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Cancer-associated fibroblasts (CAFs) have been shown to play a strong role in colorectal cancer metastasis, yet the underlying mechanism remains to be fully elucidated. Using CRC clinical samples together with ex vivo CAFs-CRC co-culture models, we found that CAFs induce expression of Leucine Rich Alpha-2-Glycoprotein 1(LRG1) in CRC, where it shows markedly higher expression in metastatic CRC tissues compared to primary tumors. We further show that CAFs-induced LRG1 promotes CRC migration and invasion that is concomitant with EMT (epithelial-mesenchymal transition) induction. In addition, this signaling axis has also been confirmed in the liver metastatic mouse model which displayed CAFs-induced LRG1 substantially accelerates metastasis. Mechanistically, we demonstrate that CAFs-secreted IL-6 (interleukin-6) is responsible for LRG1 up-regulation in CRC, which occurs through a direct transactivation by STAT3 following JAK2 activation. In clinical CRC tumor samples, LRG1 expression was positively correlated with CAFs-specific marker, α-SMA, and a higher LRG1 expression predicted poor clinical outcomes especially distant metastasis free survival, supporting the role of LRG1 in CRC progression. Collectively, this study provided a novel insight into CAFs-mediated metastasis in CRC and indicated that therapeutic targeting of CAFs-mediated IL-6-STAT3-LRG1 axis might be a potential strategy to mitigate metastasis in CRC.Subject terms: Colon cancer, Cancer microenvironment  相似文献   
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镉离子诱导BA/F3β细胞发生奇特的细胞凋亡   总被引:2,自引:0,他引:2  
细胞凋亡一般都伴随有DNA 片段化, 活性氧含量增加, 并能被过量的Bcl2 所抑制。以BA/F3β细胞为模型, 利用MTT 检测、Hochest 染色以及透射电镜检测等技术却发现, 镉离子虽然可以诱导该细胞凋亡, 但是这种凋亡没有DNA 片段化, 也没有活性氧含量增加。此外, 过量Bcl2 对这种凋亡也没有保护作用。因此, 可以确认镉离子诱导BA/F3β细胞发生了奇特的细胞凋亡。  相似文献   
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Ljubkovic M  Shi Y  Cheng Q  Bosnjak Z  Jiang MT 《FEBS letters》2007,581(22):4255-4259
Previous observations on the activation of the mitochondrial ATP-sensitive potassium channel (mitoK(ATP)) by nitric oxide (NO) in myocardial preconditioning were based on indirect evidence. In this study, we have investigated the direct effect of NO on the rat cardiac mitoK(ATP) after reconstitution of the inner mitochondrial membranes into lipid bilayers. We found that the mitoK(ATP) was activated by exogenous NO donor S-nitroso-N-acetyl penicillamine or PAPA NONOate. This activation was inhibited by mitoK(ATP) blockers 5-hydroxydecanoate or glibenclamide. Our observations confirm that NO can directly activate the cardiac mitoK(ATP), which may underlie its contribution to myocardial preconditioning.  相似文献   
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Three A–π–A or D–π–D perylene diimide ( PDI ) derivatives with varied groups on π-conjugate were synthesized and characterized. The photophysical properties of these compounds were systematically studied by spectral experiments and density functional theory calculations. All compounds displayed intense absorption bands at 300–800 nm wavelengths. However, diverse groups on the π-conjugate influenced the UV–vis absorption. Electron-withdrawing groups on PDI-2 caused a slight red shift at the 350–400 nm wavelength and a blue shift after 400 nm wavelength. At the same time, the electron-donating substituents on PDI-3 caused an obvious red shift of this band. These PDI derivatives exhibited emission in solution at room temperature (λem = 500–850 nm). The quantum yield of PDI-3 decreased, while the electron-donating substituents were introduced to the π-conjugated motifs. However, the quantum yield of PDI-2 increased when electron-withdrawing substituents were introduced to the π-conjugated motifs. In addition, PDI-1 and PDI-2 exhibited broad triplet transient absorption in the visible region. These photophysical properties could help us to understand the relationship between structure and photophysical properties of perylene diimide derivatives and exploit more original perylene diimide-based optical functional materials.  相似文献   
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