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91.
92.
Melanoma is an aggressive skin malignancy with a high mortality rate; however, successful treatment remains a clinical challenge. Ivermectin, a broad-spectrum antiparasitic drug, has recently been characterized as a potential anticancer agent due to its observed antitumor effects. However, the molecular mechanisms of ivermectin remain poorly understood. In the current study, we tested the involvement of autophagy in the ivermectin mechanism of action in human melanoma cells. We exposed SK-MEL-28 cells to different concentrations of ivermectin (2.5, 5, and 10 μM) for 24 hours. Here, ivermectin-induced apoptosis, as evidenced by the upregulation of cleaved poly (ADP-ribose) polymerase, BAX expression, and caspase-3 activity and downregulation of BCL-2 expression. In line with the apoptosis response, ivermectin triggered autophagy. Pharmacological or genetic inhibition of autophagy further sensitized SK-MEL-28 cells to ivermectin-induced apoptosis. Mechanistically, ivermectin-induced TFE3(Ser321) dephosphorylation, activated TFE3 nuclear translocation and increased TFE3 reporter activity, which contributed to lysosomal biogenesis and the expression of autophagy-related genes, and subsequently, initiated autophagy in SK-MEL-28 cells. Moreover, N-acetyl-cysteine, an reactive oxygen species (ROS) scavenger, abrogated the effects of ivermectin on TFE3-dependent autophagy. Taken together, we demonstrated that ivermectin increases TFE3-dependent autophagy through ROS signaling pathways in human melanoma cells and that inhibiting autophagy enhances ivermectin-induced apoptosis in human melanoma cells. 相似文献
93.
Xie C Kang J Li Z Schauss AG Badger TM Nagarajan S Wu T Wu X 《The Journal of nutritional biochemistry》2012,23(9):1184-1191
Recent studies have shown that some flavonoids are modulators of proinflammatory cytokine production. In this study, velutin, a unique flavone isolated from the pulp of açaí fruit (Euterpe oleracea Mart.), was examined for its effects in reducing lipopolysaccharide-induced proinflammatory cytokine tumor necrosis factor (TNF)-α and interleukin (IL)-6 production in RAW 264.7 peripheral macrophages and mice peritoneal macrophages. Three other structurally similar and well-studied flavones, luteolin, apigenin and chrysoeriol, were included as controls and for comparative purposes. Velutin exhibited the greatest potency among all flavones in reducing TNF-α and IL-6 production. Velutin also showed the strongest inhibitory effect in nuclear factor (NF)-κB activation (as assessed by secreted alkaline phosphatase reporter assay) and exhibited the greatest effects in blocking the degradation of inhibitor of NF-κB as well as in inhibiting mitogen-activated protein kinase p38 and JNK phosphorylation; all of these are important signaling pathways involved in production of TNF-α and IL-6. The present study led to the discovery of a strong anti-inflammatory flavone, velutin. This compound effectively inhibited the expression of proinflammatory cytokines TNF-α and IL-6 in low micromole levels by inhibiting NF-κB activation and p38 and JNK phosphorylation. 相似文献
94.
Among the components that make up a lateral-flow immunochromatographic assay (ICA), antibody is the key. In this paper, salbutamol (SAL) as a model analyte was meticulously designed to prepare immunogen and coating antigen in distinctly different ways. Four hybridoma cell lines were prepared and identified. Among them, C9 had highest affinity, best dose-response behavior, lowest limit of detection, and highest specificity and was chosen to be labeled with colloidal gold as the detector reagent and applied on the conjugate pad. Goat anti-mouse antibody and SAL-BSA conjugate were sprayed on a nitrocellulose membrane as test line and control line, respectively. Under the optimized conditions, the ICA strip was constructed based on a binding inhibition format. Color intensity on the test line was visually distinguishable from that of the negative sample within 5 min, with the visual detection limit of 1 ngml(-1) in phosphate-buffered saline. Cross-reactions with other β-agonists were not found (<1%). The results from ICA were in a good agreement with those obtained by enzyme-linked immunosorbent assay. The developed ICA has potential as a useful on-site screening tool for SAL in swine urine. 相似文献
95.
Human saliva contains a large number of proteins and peptides (salivary proteome) that help maintain homeostasis in the oral cavity. Global analysis of human salivary proteome is important for understanding oral health and disease pathogenesis. In this study, large-scale identification of salivary proteins was demonstrated by using shotgun proteomics and two-dimensinal gel electrophoresis-mass spectrometry (2-DE-MS). For the shotgun approach, whole saliva proteins were prefractionated according to molecular weight. The smallest fraction, presumably containing salivary peptides, was directly separated by capillary liquid chromatography (LC). However, the large protein fractions were digested into peptides for subsequent LC separation. Separated peptides were analyzed by on-line electrospray tandem mass spectrometry (MS/MS) using a quadrupole-time of flight mass spectrometer, and the obtained spectra were automatically processed to search human protein sequence database for protein identification. Additionally, 2-DE was used to map out the proteins in whole saliva. Protein spots 105 in number were excised and in-gel digested; and the resulting peptide fragments were measured by matrix-assisted laser desorption/ionization-mass spectrometry and sequenced by LC-MS/MS for protein identification. In total, we cataloged 309 proteins from human whole saliva by using these two proteomic approaches. 相似文献
96.
Li S Xie L Zhang C Zhang Y Gu M Zhang R 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2004,138(3):235-243
The shells of bivalves are mainly composed of calcium carbonate, a product of calcium metabolism. In the process of shell formation, the uptake, transport and recruitment of calcium ion are highly regulated and involved in many factors. Among these regulatory factors, calmodulin (CaM), a pivotal multifunction regulator of calcium metabolism in nearly all organisms, is thought to play an important role in the calcium metabolism involved in shell formation. In this study, a full-length CaM cDNA was isolated from the pearl oyster (Pinctada fucata). The oyster calmodulin encodes a 16.8 kDa protein which shares high similarity with vertebrate calmodulin. The oyster CaM mRNA shows the highest level of expression in the gill, a key organ involved in calcium uptake in oyster calcium metabolism. In situ hybridization results revealed that oyster CaM mRNA is expressed at the folds and the outer epithelial cells of the dorsal region of the mantle, suggesting that CaM is involved in regulation of calcium transport and secretion. Oyster CaM also showed a typical Ca2+ dependent electrophoretic shift characterization and calcium binding activity. Taken together, we have identified and characterized a pivotal calcium metabolism regulator of the oyster that may play an important role in regulation of calcium uptake, transport and secretion in the process of shell formation. 相似文献
97.
A mixed culture of moderately thermophilic microorganisms was enriched from acid mine drainage samples collected from several chalcopyrite mines in China. Such mixed culture can be used to effectively extract copper from chalcopyrite. Furthermore, after being adapted to gradually increased concentration of chalcopyrite concentrate, the tolerance of the mixed culture to chalcopyrite concentrate was brought up to 80 g/L. The effects of several leaching parameters on copper recovery in stirred tank reactor also had been investigated. The results of the investigation show that it was possible to achieve a copper extraction rate of 75% in 44 days at a pulp density of 8%. The leaching rate of chalcopyrite concentrate tended to increase with dissolved total iron concentration. At low pH ranges, more microscopic counts of microorganisms were found in the solution. Furthermore, the analysis of leached residues indicates that the passivation of chalcopyrite concentrate was mainly due to a mass of jarosite and PbSO(4) on the mineral surface, other than the elemental sulphur layer. The bacterial community composition was analyzed by using Amplified Ribosomal DNA Restriction Analysis. Two moderately thermophilic bacteria species were identified as Leptospirillum ferriphilum and Acidithiobacillus caldus with abundance of 67% and 33% in the bio-pulp, respectively. 相似文献
98.
99.
Polysaccharides influence concentration and purity of extracted DNA. Here we present rapid and efficient protocol for DNA extraction from samples rich in polysaccharides. The technique has been developed using cultures of Schizophyllum commune and involves a modification of known Cetyltrimethyl Ammonium Bromide (CTAB) protocol. To remove polysaccharides, Polyethylene Glycol (PEG) 8000 was added during DNA precipitation. Genomic DNA obtained with the CTAB-PEG method had high integrity, with average fragment size >30 kb, the concentration higher than 100 ng/μL, and the yield more than 30 μg/g. Presented technique is suitable for DNA extraction from fungi, bacteria, archaea or even mollusks with high polysaccharide content. 相似文献
100.
Hongxu Wu Shifang Yang Xiaojie Wu Junling Zhao Jianping Zhao Qin Ning Yongjian Xu Jungang Xie 《Biochemical and biophysical research communications》2014
Interleukin-33 is a newly described member of the interleukin-1 family. Recent research suggests that IL-33 is increased in lungs and plays a critical role in chronic airway inflammation in cigarette smoke-induced chronic obstructive pulmonary disease (COPD) mice. To determine the role of IL-33 in systemic inflammation, we induced COPD mice models by passive cigarette smoking and identified the IL-33 expression in bronchial endothelial cells and peripheral blood mononuclear cells (PBMCs) of them. After isolation, PBMCs were cultured and stimulated in vitro. We measured expressions of interleukin-6 and interleukin-8 in PBMCs in different groups. The expression of IL-33 in bronchial endothelial cells and PBMCs of COPD mice were highly expressed. Stimulated by cigarette smoke extract (CSE), the expression of IL-6 and IL-8 were induced and enhanced by IL-33. PBMCs of COPD mice produced more IL-6 and IL-8 stimulated by CSE and IL-33. Expression of IL-6 and IL-8 were decreased when stimulated by IL-33 together with soluble ST2. The mRNA production of ST2 in IL-33 stimulated PBMCs was increased. Being pretreated with several kinds of MAPK inhibitors, the secretions of IL-6 and IL-8 in PBMCs did not decrease except for the p38 MAPK inhibitor. We found that IL-33 could induce and enhance the expression of IL-6 and IL-8 in PBMCs of COPD mice via p38 MAPK pathway, and it is a promoter of the IL-6 and IL-8 production in systemic inflammation in COPD mice. 相似文献