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International Microbiology - Gallbladder and biliary tract infections are diseases with high mortality rates if they are not treated properly. Microbiological evaluation of perioperatively...  相似文献   
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Novel enamine derivatives were synthesized from the reaction of lactone and chalcones and their antiproliferative and cytotoxic activities against six cancer cell lines (e. g., HeLa, HT29, A549, MCF7, PC3 and Hep3B) and one normal cell lines (e. g., FL) were investigated along with their mode of interactions with CT‐DNA. Most of the enamine derivatives with IC50 values of 86–168 μM demonstrated much stronger antiproliferative activity than the starting molecules against the cancer cells. While, among the enamine derivatives, four compounds displayed higher cytotoxic potency than the control drugs (5‐fluorouracil and cisplatin) against the Hep3B cell lines, these compounds did not exhibit any significant toxicity against normal cells, FL. The UV/VIS spectral data suggest that eight compounds cause hypochromism with a slight bathochromic shift (~6 nm), indicating that they bind to the DNA by way of an intercalative or minor groove binding mode. The binding constants of the compounds are in the range of 0.1×103 M?1–2.3×104 M?1. The antiproliferative activity of studied enamine derivatives could possibly be due to their DNA binding as well as their cytotoxic properties. In addition to these assays, the chalcones and enamine derivatives were investigated by molecular docking to calculate the synergistic effect of antiproliferative activities against six human cancer cell lines.  相似文献   
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Hematopoietic stem cells (HSCs) are known to reside in a bone marrow (BM) niche, which is associated with relatively higher calcium content. HSCs sense and respond to calcium changes. However, how calcium-sensing components modulate HSC function and expansion is largely unknown. We investigated temporal modulation of calcium sensing and Ca2+ homeostasis during ex vivo HSC culture and in vivo. Murine BM-HSCs, human BM, and umbilical cord blood (UCB) mononuclear cells (MNCs) were treated with store-operated calcium entry (SOCE) inhibitors SKF 96365 hydrochloride (abbreviated as SKF) and 2-aminoethoxydiphenyl borate (2-APB). Besides, K+ channel inhibitor TEA chloride (abbreviated as TEA) was used to compare the relationship between calcium-activated potassium channel activities. Seven days of SKF treatment induced mouse and human ex vivo BM-HSC expansion as well as UCB-derived primitive HSC expansion. SKF treatment induced the surface expression of CaSR, CXCR4, and adhesion molecules on human hematopoietic stem and progenitor cells. HSCs expanded with SKF successfully differentiated into blood lineages in recipient animals and demonstrated a higher repopulation capability. Furthermore, modulation of SOCE in the BM-induced HSC content and differentially altered niche-related gene expression profile in vivo. Intriguingly, treatments with SOCE inhibitors SKF and 2-APB boosted the mouse BM mesenchymal stem cell (MSC) and human adipose-derived MSCs proliferation, whereas they did not affect the endothelial cell proliferation. These findings suggest that temporal modulation of calcium sensing is crucial in expansion and maintenance of murine HSCs, human HSCs, and mouse BM-MSCs function.  相似文献   
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This study was aimed at investigating and comparing the effects of exogenous glycinebetaine (GB) and trehalose (TR) on lead (Pb) accumulation in Lemna gibba. Two-way ANOVA showed that both GB and TR had significant effects on Pb accumulation. However, TR seemed to be more effective than GB. It was determined that 5 mM GB application decreased Pb accumulation whereas 0.5 mM TR increased and 2 and 5 mM decreased Pb accumulation. The results obtained from this study will be useful for examining the phytoremediation of polluted water using aquatic plants.  相似文献   
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Panomycocin, a novel exo-beta 1,3 glucanase, was tested as an antifungal agent against green and blue mold diseases, the most important causes of post harvest decay in citrus fruits. All tested isolates of Penicillium digitatum and Penicillium italicum were susceptible to panomycocin in vitro. Effective panomycocin concentrations for 50% growth inhibition (MIC-2) for P. digitatum and P. italicum were 2 and 1 μg ml−1, respectively. Complete (MIC-0) growth inhibition of all isolates observed at a panomycocin concentration of 16 μg ml−1. Treatment of spores with panomycocin at values lower than the MIC-0 led to slower germ tube elongation and mycelium growth. In tests on fruit, panomycocin at concentrations equal to in vitro MIC-0 value protected lemon fruit from decay.  相似文献   
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