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Find video protocols related to scientific articles indexed in Pubmed.
Triazole Containing Novobiocin and Biphenyl Amides as Hsp90 C-Terminal Inhibitors.
Medchemcomm
PUBLISHED: 10-21-2014
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Hsp90 C-terminal inhibitors are advantageous for the development of new cancer chemotherapeutics due to their ability to segregate client protein degradation from induction of the prosurvival heat shock response, which is a major detriment associated with Hsp90 N-terminal inhibitors under clinical investigation. Based upon prior SAR trends, a 1,2,3-triazole side chain was placed in lieu of the aryl side chain and attached to both the coumarin and biphenyl scaffold. Antiproliferative studies against SKBr3 and MCF-7 breast cancer cell lines demonstrated these triazole-containing compounds to exhibit improved activity. These compounds were shown to manifest Hsp90 inhibitory activity through Western blot analysis and represent a new scaffold upon which more potent inhibitors can be pursued.
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Regioselective radical aminofluorination of styrenes.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 08-27-2014
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The copper-catalyzed radical aminofluorination of styrenes with N-fluorobenzenesulfonimide (NFSI) is realized with high regioselectivity, thus affording aminofluorination products with regioselectivities opposite that of the palladium-catalyzed and noncatalyzed processes. Preliminary mechanistic studies suggested the reaction went through a radical pathway and was supported by DFT calculations. In these reactions, NFSI is utilized as both a radical nitrogen source and radical fluorine source, thus rendering it an attractive reagent.
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Ethylene transposition: ruthenium hydride catalyzed intramolecular trans-silylvinylation of internal alkynes.
Org. Lett.
PUBLISHED: 08-12-2014
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A highly selective intramolecular trans-silylvinylation of internal alkynes catalyzed by RuHCl(CO)(SIMes)(PPh3) has been accomplished. The use of methyl vinyl ketone as an additive increased the efficiency of this transformation. This process was used to successfully form five-, six-, and seven-membered oxasilacycles by a formal anti-exo-dig cyclization.
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Reuse of drinking water treatment residuals in a continuous stirred tank reactor for phosphate removal from urban wastewater.
Environ Technol
PUBLISHED: 05-27-2014
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This work proposed a new approach of reusing drinking water treatment residuals (WTR) in a continuous stirred tank reactor (CSTR) to remove phosphate (P) from urban wastewater. The results revealed that the P removal efficiency of the WTR was more than 94% for urban wastewater, in the condition of initial P concentration (P0) of 10 mg L(-1), hydraulic retention time (HRT) of 2 h and WTR dosage (M0) of 10 g L(-1). The P mass transfer from the bulk to the solid-liquid interface in the CSTR system increased at lower P0, higher M0 and longer HRT. The P adsorption capacity of WTR from urban wastewater was comparable to that of the 201×4 resin and unaffected by ions competition. Moreover, WTR had a limited effect on the metals' (Fe, Al, Zn, Cu, Mn and Ni) concentrations of the urban wastewater. Based on the principle of waste recycling, the reuse of WTR in CSTR is a promising alternative technology for P removal from urban wastewater.
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A microporous Zn(II)-MOF with open metal sites: structure and selective adsorption properties.
Dalton Trans
PUBLISHED: 04-15-2014
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A three-dimensional microporous framework, Zn(II)-MOF [Zn(HPyImDC)(DMA)]n (1) (H3PyImDC = 2-(pyridine-4-yl)-1H-4,5-imidazoledicarboxylic, DMA = N,N'-dimethylacetamide), with open metal sites and small-sized pores, exhibits excellent selective capture of CO2 over N2 and CH4 at 273 K, as well as alcohols from water. The excellent CO2 adsorption selectivity of 1 allows its potential use in the capture of CO2 from industrial flue gas or the removal of CO2 from natural gas. More interestingly, compound represents the rare case of porous materials separating propanol isomers, which may be caused by the relative flexibility of the linear n-propanol considering that both n-propanol and i-propanol have similar kinetic diameters.
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Development of radamide analogs as Grp94 inhibitors.
Bioorg. Med. Chem.
PUBLISHED: 04-10-2014
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Hsp90 isoform-selective inhibition is highly desired as it can potentially avoid the toxic side-effects of pan-inhibition. The current study developed selective inhibitors of one such isoform, Grp94, predicated on the chimeric and pan-Hsp90 inhibitor, radamide (RDA). Replacement of the quinone moiety of RDA with a phenyl ring (2) was found to be better suited for Grp94 inhibition as it can fully interact with a unique hydrophobic pocket present in Grp94. An extensive SAR for this scaffold showed that substitutions at the 2- and 4-positions (8 and 27, respectively) manifested excellent Grp94 affinity and selectivity. Introduction of heteroatoms into the ring also proved beneficial, with a 2-pyridine derivative (38) exhibiting the highest Grp94 affinity (K(d)=820 nM). Subsequent cell-based assays showed that these Grp94 inhibitors inhibit migration of the metastatic breast cancer cell line, MDA-MB-231, as well as exhibit an anti-proliferative affect against the multiple myeloma cell line, RPMI 8226.
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A highly stable multifunctional three-dimensional microporous framework: excellent selective sorption and visible photoluminescence.
Dalton Trans
PUBLISHED: 03-21-2014
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A Cd(II)-MOF [Cd(L)(DMF)] (1) (H2L = 5-(4-pyridyl)-isophthalic acid) featuring high thermal and chemical stability has been solvothermally synthesized and characterized. Complex 1 is a robust multifunctional three-dimensional (3D) microporous framework possessing an unusual (4,5)-connected topological net. Activated 1 shows high-efficiency for the selective capture of CO2 over N2 and CH4 under ambient conditions, which ranks it among MOFs with the highest selectivity. In addition, desolvated 1 exhibits good separation ratios of H2 over N2 at lower temperature, as well as alcohols from water. In particular, desolvated 1 demonstrates significantly higher adsorption enthalpies for CO2 and CH4 gas molecules, which are in the range of the highest Q(st) values reported to date. Furthermore, complex 1 displays visible photoluminescence in the solid state under UV irradiation.
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EphB4 regulates the growth and migration of pancreatic cancer cells.
Tumour Biol.
PUBLISHED: 02-11-2014
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Pancreatic cancer is a serious threat to human life. Moreover, its treatment is complicated and its prognosis is very poor. Therefore, a new method for the diagnosis and treatment of pancreatic cancer is very essential. In this study, a eukaryotic expression plasmid targeting EphB4 was constructed and transfected into PANC-1 pancreatic cancer cells to investigate the inhibition of cell growth and the progression of iRNA against EphB4. This study provides the basis for the gene therapy of pancreatic cancer. The recombinant eukaryotic EphB4 expression plasmid, pSIREN-RetroQ-ZsGreen-EphB4 and a negative control plasmid, pSIREN-RetroQ-ZsGreen-N, were constructed. At 48 h after transfection, the relative messenger RNA (mRNA) and protein levels of EphB4 were measured by RT-PCR and western blot. The proliferation of the transfected cells was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, while cell migration ability was analyzed using the scratch migration assay. At 48 h after transient transfection, EphB4 mRNA expression was significantly decreased in transfected PANC-1 cells as compared to the control group (P < 0.01). In vitro, inhibition of EphB4 expression weakened the proliferation and cell migration ability of PANC-1 cells compared to the control group. The small interfering RNA (siRNA) eukaryotic expression plasmid vector targeting EphB4 was successfully constructed and effectively transfected into PANC-1 cells. The recombinant plasmid can inhibit the expression of EphB4 mRNA and protein in PANC-1 cells, as well as cell growth and migration.
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XB130 Deficiency Affects Tracheal Epithelial Differentiation during Airway Repair.
PLoS ONE
PUBLISHED: 01-01-2014
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The repair and regeneration of airway epithelium is important for maintaining homeostasis of the respiratory system. XB130 is an adaptor protein involved in the regulation of cell proliferation, survival and migration. In the human trachea, XB130 is expressed on the apical site of ciliated epithelial cells. We hypothesize that XB130 may play a role in epithelial repair and regeneration after injury. Xb130 knockout (KO) mice were generated, and a mouse isogenic tracheal transplantation model was used. Adult Xb130 KO mice did not show any significant anatomical and physiological phenotypes in comparison with their wild type (WT) littermates. The tracheal epithelium in Xb130 KO mice, however, was significantly thicker than that in WT mice. Severe ischemic epithelial injury was observed immediately after the tracheal transplantation, which was followed by epithelial cell flattening, proliferation and differentiation. No significant differences were observed in terms of initial airway injury and apoptosis. However, at Day 10 after transplantation, the epithelial layer was significantly thicker in Xb130 KO mice, and associated with greater proliferative (Ki67+) and basal (CK5+) cells, as well as thickening of the connective tissue and fibroblast layer between the epithelium and tracheal cartilages. These results suggest that XB130 is involved in the regulation of airway epithelial differentiation, especially during airway repair after injury.
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Effects of environmental factors on sulfamethoxazole photodegradation under simulated sunlight irradiation: kinetics and mechanism.
J Environ Sci (China)
PUBLISHED: 11-07-2013
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To advance the knowledge of the environmental fate of sulfamethoxazole (SMX), we systematically investigated the effects of natural water constituents and synthetic substances (i.e., TiO2 nanoparticles (nTiO2) and Ti-doped beta-Bi2O3 (NTB)) on the photodegradation kinetics of SMX under xenon lamp irradiation. The photolysis of SMX in aqueous solution followed first-order kinetics. Our results showed that higher concentrations of SMX, fulvic acid, suspended sediments, NTB and higher pH value decreased the photodegradation rates of SMX, whereas H2O2 improved the SMX photodegradation. TiO2 nanoparticles had a dual effect on photodegradation due to their photocatalytic activity and photoabsorption of photons. No intermediates more toxic toward Vibrio fischeri than SMX were produced after direct photolysis and photocatalytic degradation for 3 hr. The photolysis of SMX involved three pathways: hydroxylation, cleavage of the sulfonamide bond, and fragmentation of the isoxazole ring. This study lays the groundwork for a better understanding of the environmental fate of SMX.
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?1-Antitrypsin inhibits ischemia reperfusion-induced lung injury by reducing inflammatory response and cell death.
J. Heart Lung Transplant.
PUBLISHED: 05-31-2013
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Pulmonary ischemia-reperfusion (IR)-induced lung injury is a severe complication that increases the likelihood of primary graft dysfunction and early death after lung transplantation. Inflammatory cytokine release and cell death play a critical role in the development of IR-induced lung injury. ?1-Antitrypsin (A1AT) is a protease inhibitor clinically used for the treatment of A1AT-deficiency emphysema. On the basis of a literature review, we hypothesize that A1AT may have the potential to reduce IR-induced lung injury through its anti-inflammatory and anti-apoptotic effects.
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Visible-light-mediated Sr-Bi2O3 photocatalysis of tetracycline: kinetics, mechanisms and toxicity assessment.
Chemosphere
PUBLISHED: 01-03-2013
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Photodegradation of tetracycline (TC) was investigated in aqueous solution by visible-light-driven photocatalyst Sr-doped ?-Bi2O3 (Sr-Bi2O3) prepared via solvothermal synthesis. The decomposition of TC by Sr-Bi2O3 under visible light (?>420nm) irradiation followed pseudo-first-order kinetics, and the removal ratio reached 91.2% after 120min of irradiation. Sr-Bi2O3 photocatalysis is able to break the naphthol ring of TC which decomposes to m-cresol via dislodging hydroxyl group step by step by photogenerated electron. This mechanism was verified by electron spin resonance measurement, the addition of radical scavengers and the intermediate product analysis, indicating that the photogenerated electron acts as a reductant and can be the key to the degradation process. In contrast, in TiO2 photocatalysis the naphthol ring is broken via oxidation by hydroxyl radical, while in direct photolysis the ring remains intact. In addition, the toxicity of photodegradation products was analyzed by bioluminescence inhibition. After 120min of irradiation by Sr-Bi2O3, the toxicity decreases by 90.6%, which is more substantial than direct photolysis (70%) and TiO2 photocatalysis (80%), indicating that the Sr-Bi2O3 photocatalysis is more eco-friendly than the other two methods.
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Six new metal-organic frameworks with multi-carboxylic acids and imidazole-based spacers: syntheses, structures and properties.
Dalton Trans
PUBLISHED: 10-05-2011
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Six new metal-organic frameworks [Cu(obba)(bimb)·(obbaH(2))](n) (1), [Cu(obba)(bimb)](n) (2), [Zn(2)(obba)(2)(bimb)(2)(DMF)(2)(H(2)O)(3.5)](n) (3), [Ni(3)(2,2,4,4-bptcH)(2)(bimb)(2)(H(2)O)(2)·(H(2)O)(2)](n) (4), [Ni(2)(bimb)(3)(H(2)O)(6)·(aobtc)·(DMF)(2)·(H(2)O)(2)](n) (5) and [Cd(3,3,4,4-bptcH(2))(H(2)O)·(bimb)](n) (6), were obtained by reactions of 4,4-bis(1-imidazolyl)biphenyl (bimb) and multi-carboxylic acids of 4,4-oxybis(benzoic acid) (obbaH(2)), 2,2,4,4-biphenyltetracarboxylate acid (2,2,4,4-bptcH(4)), azoxybenzene-3,3,5,5-tetracarboxylic acid (aobtcH(4)), and 3,3,4,4-biphenyltetracarboxylate acid (3,3,4,4-bptcH(4)) with corresponding metal salts under hydro/solvothermal conditions, respectively. Complexes 1-3 have entangled structures with different topologies: 1 is a 3-fold interpenetrating NbO three-dimensional (3D) network; 2 is a 3-fold interpenetrating dmp 3D net; 3 is a 6-fold interpenetrating dia 3D chiral net containing rare 1D helical chains with the same handedness. Complex 4 is an uninodal 6-connected network with a Schäfli symbol of (4(8)6(4)8(3)) based on the trinuclear Ni(II) subunits, while complexes 5 and 6 are 1D chains. Interestingly, compound 6 represents the rare example of MOFs that exhibit high photocatalytic activity for dye degradation under visible light and shows good stability towards photocatalysis. Complexes 3 and 6 exhibit intense blue emissions in the solid state at room temperature whereas 3 appears to be a good candidate of novel hybrid inorganic-organic NLO material.
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Asterosaponin 1 induces endoplasmic reticulum stress-associated apoptosis in A549 human lung cancer cells.
Oncol. Rep.
PUBLISHED: 05-09-2011
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Asterosaponin 1, a new cytostatic agent from starfish, possesses several bioactivities including an antitumor effect. The aim of this study was to investigate the potential anti-proliferative and pro-apoptotic activity of asterosaponin 1 in A549 human lung cancer cells, as well as the potential mechanisms. The results showed that asterosaponin 1 inhibited the proliferation of A549 cells in a dose-dependent manner, and the cytostatic activity resulted from the induction of apoptotic cell death. Asterosaponin 1 increased ER dilation and cytosolic Ca2+ concentration, and enhanced the expression of the ER molecular chaperones GRP78 and GRP94 in a dose- and time-dependent manner. In addition, asterosaponin 1 treated A549 cells exerted increased expression and activity of CHOP, caspase-4 and JNK, three essential ER-associated apoptotic molecules. In summary, these results demonstrated that asterosaponin 1 inhibits the proliferation of A549 cells through induction of ER stress-associated apoptosis, making asterosaponin 1 a candidate new anticancer drug for lung cancer therapy.
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Identification of GIRK2-4 subunits in human esophageal smooth muscle cells.
Mol Med Rep
PUBLISHED: 02-18-2011
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Acetylcholine (ACh) secreted from the vagus nerve contributes to the physiological and pathological regulation of the contraction and relaxation of human esophageal smooth muscle. Expression of acetylcholine-sensitive G protein?activated inwardly rectifying potassium channels (GIRKs) occurs widely in the heart, nervous system and gastrointestine, but the role of GIRKs in the esophagus remains unclear. In the present study, expression of the GIRK1-4 subunits in mRNA and total protein was examined in human esophageal smooth muscle cells (SMCs) by reverse transcription polymerase chain reaction (RT-PCR) and Western blotting. mRNA and protein expression of the GIRK2-4 subunits was detected in human esophageal longitudinal muscle (LM) and circular muscle (CM) cells. However, GIRK1 mRNA and protein were not observed in either the esophageal LM or CM. This study is the first to identify the expression of GIRK2-4 subunits in human esophageal SMCs.
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n-3 polyunsaturated fatty acids prevents atrial fibrillation by inhibiting inflammation in a canine sterile pericarditis model.
Int. J. Cardiol.
PUBLISHED: 02-11-2010
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It has been recently reported that atrial fibrillation (AF) is associated with inflammation and inflammatory cytokines, and n-3 polyunsaturated fatty acids (PUFAs) might be of anti-inflammatory effects. This study was to evaluate the anti-inflammatory effect of PUFAs on AF in a canine sterile pericarditis model.
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Intraoperative recurrent laryngeal nerve monitoring during surgery for left lung cancer.
J. Thorac. Cardiovasc. Surg.
PUBLISHED: 01-01-2010
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This study evaluated the safety and efficacy of intraoperative recurrent laryngeal nerve monitoring during surgery for left lung cancer.
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Experimental and theoretical study of tunable 1,3-lithium shift of propargylic/allenylic species, transmetallation, and Pd-catalyzed cross-coupling reactions.
Chemistry
PUBLISHED: 09-18-2009
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The highly selective tuning of the isomerization from 1-arylalka-1,2-dien-1-yllithium to 1-arylalka-1,2-dien-3-yllithium has been realized in the deprotonation of 1-arylalk-1-yne (conditions A and B) and carbolithiation of 1-arylbut-3-en-1-yne with alkyllithium (conditions C and D). Subsequent transmetallation and Pd-catalyzed Negishi coupling reactions afforded 1,1-diaryl or 1,3-diaryl allenes with high selectivity. Deuterium-labeling cross experiments indicated that an intermolecular lithiation process occurred in both 1,3-lithium shift conditions (conditions B and D). 1-Arylalka-1,2-diene was confirmed experimentally to be the intermediate. A computational study at the B3LYP level for the isomerization indicated that the acidity of H at the 3-position is higher than that of the H at the 1-position of 1-phenyl-1,2-butadiene. Under conditions B, iPr(2)NH acts as a proton carrier to finish the 1,3-lithium shift. The overall activation barrier for the rate-determining step in the solvated models is approximately 21.0 kcal mol(-1), indicating that the isomerization is reasonable at room temperature. For the isomerization under conditions D, DFT calculations indicated that the addition of TMEDA (tetramethylethylenediamine) and HMPA (hexamethylphosphoramide) changes the global minimum of the system; among the possible mechanisms (P1-P5) considered, the mechanism catalyzed by dilithiated species (P5) is the most probable one. The overall activation barriers for isomerization in THF and TMEDA solvated models are 22.6 and 19.7 kcal mol(-1), respectively, proving that the isomerization may proceed at RT in THF or at -78 degrees C with TMEDA, due to the fact that the solvation of the additives may increase the concentration of 1-phenyl-1,2-butadienyllithium monomer by a deaggregation effect.
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Sustained local application of epidermal growth factor to accelerate reepithelialization of tracheal grafts.
J. Thorac. Cardiovasc. Surg.
PUBLISHED: 08-15-2009
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Epidermal growth factor-loaded gelatin microspheres were tested for potential to accelerate tracheal allograft reepithelialization.
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Single immunoglobulin IL-1 receptor-related protein attenuates the lipopolysaccharide-induced inflammatory response in A549 cells.
Chem. Biol. Interact.
PUBLISHED: 07-22-2009
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The lipopolysaccharide (LPS)-Toll-like receptor 4 (TLR4) signaling pathway in alveolar epithelial cells plays an important role in many pathologic processes such as acute lung injury (ALI). The single immunoglobulin IL-1 receptor-related protein (SIGIRR) is an inhibitor of LPS-TLR4 signaling, but its expression and function in alveolar epithelial cells are still unknown. In this study, we examined the expression of SIGIRR in normal human lung tissue using immunohistochemistry, reverse transcription-PCR (RT-PCR) and Western blot and found that SIGIRR was expressed in alveolar epithelial cells. Treatment of an alveolar epithelial cell line, A549, with LPS and we observed a downregulation of SIGIRR mRNA, which returned to normal levels 24h after LPS exposure. A549 cells were then transfected with a SIGIRR eukaryotic expression vector to over-express SIGIRR or, as a control, with an empty vector. Following LPS exposure, the transcriptional activity of NF-kappaB was measured using a dual-luciferase reporter assay system, and the concentration of IL-1beta, TNF-alpha and IL-6 was determined by ELISA, and cell proliferation was measured by MTT. In A549 cells that over-expressed SIGIRR, LPS treatment resulted in a significant decrease in the transcriptional activity of NF-kappaB and cell growth inhibition ratio, as well as lower levels of secreted IL-1beta, TNF-alpha and IL-6. In conclusion, SIGIRR in A549 cells inhibits the transcriptional activity of NF-kappaB and reduces the amount cytokines produced, protecting these cells from acute LPS-induced damage.
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Upregulated fascin1 in non-small cell lung cancer promotes the migration and invasiveness, but not proliferation.
Cancer Lett.
PUBLISHED: 07-08-2009
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Fascin1, an actin-binding protein, is overexpressed in many kinds of tumors. However, its exact role in non-small cell lung cancer (NSCLC) is still unclear. We observed that expression of fascin1 was associated with lymph nodes metastasis and TNM staging but not proliferation in NSCLC by using immunohistochemistry. By generating A549 lung cancer clones stably overexpressing different fascin1 protein, we further confirmed that fascin1 could promote A549 cell migration and invasiveness in vitro and in vivo. Using cell proliferation assay, cell cycle analysis in vitro and tumorigenicity assay in vivo, we showed that fascin1 had little influence on proliferation in A549 cells. These results suggest that fascin1 plays a significant role in NSCLC metastasis and may be a target of intervening to prevent the metastasis of NSCLC.
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[Expression and its Clinical Significance of NOK, EGFR in NSCLC.].
Zhongguo Fei Ai Za Zhi
PUBLISHED: 05-27-2009
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NOK (Novel Oncogene with Kinase-domain) is a newly identified receptor protein-tyrosine kinases (RPTKs) subfamily, which possesses strong oncogenic potential including enhancing cell transformation, tumorigenesis, invasion and metastasis. However, NOK protein lacks extracellular domain, and how the NOK is activated by the membrane receptor and the expression of NOK in non small cell lung cancer (NSCLC) are not clear. Our aim of this study was to investigate the expressions of NOK, EGFR proteins in NSCLC.
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[Expression and Clinical Significance of ABCC10 in the Patients with Non-small Cell Lung Cancer.].
Zhongguo Fei Ai Za Zhi
PUBLISHED: 05-27-2009
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Multidrug resistance (MDR) is the main reason of the failure of chemotherapy in lung cancer. The MDR mechanism in lung cancer is complex, which relates to sorts of drug resistant genes. ABCC10 is a recently identified member of a subset of the C family of ATP-binding cassette (ABC) transporters. The drug resistance capability of ABCC10 has been partly determined. The aim of the study is to investigate the expression of ABCC10 in non small cell lung cancer (NSCLC) and normal tissues, and analyze the relationship between ABCC10 expression level and clinical features, such as TNM stages, histological types and pathological grades.
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CuX2-mediated halolactonization reaction of monoesters of 1,2-allenyl phosphonic acids and their Suzuki cross-coupling reaction.
J. Org. Chem.
PUBLISHED: 01-07-2009
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CuX(2)-mediated (X = Cl, Br) halolactonization of monoesters of 1,2-allenyl phosphonic acids is presented. The reaction proceeded smoothly under the mild condition for differently substituted allenic substrates giving the 4-halo-2,5-dihydro[1,2]oxaphosphole 2-oxides in good yields. The Suzuki cross-coupling reaction of these bromides and even chlorides with organic boronic acids under the catalysis of PdCl(2)(Sphos)(2) afforded 4-substituted-2,5-dihydro[1,2]oxaphosphole 2-oxides in moderate to good yields.
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New multifunctional porous materials based on inorganic-organic hybrid single-walled carbon nanotubes: gas storage and high-sensitive detection of pesticides.
Chemistry
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Single-walled carbon nanotubes (SWNTs) that are covalently functionalized with benzoic acid (SWNT-PhCOOH) can be integrated with transition-metal ions to form 3D porous inorganic-organic hybrid frameworks (SWNT-Zn). In particular, N(2)-adsorption analysis shows that the BET surface area increases notably from 645.3 to 1209.9?m(2) ?g(-1) for SWNTs and SWNT-Zn, respectively. This remarkable enhancement in the surface area of SWNT-Zn is presumably due to the microporous motifs from benzoates coordinated to intercalated zinc ions between the functionalized SWNTs; this assignment was also corroborated by NLDFT pore-size distributions. In addition, the excess-H(2)-uptake maximum of SWNT-Zn reaches about 3.1?wt.?% (12?bar, 77?K), which is almost three times that of the original SWNTs (1.2?wt.?% at 12?bar, 77?K). Owing to its inherent conductivity and pore structure, as well as good dispersibility, SWNT-Zn is an effective candidate as a sensitive electrochemical stripping voltammetric sensor for organophosphate pesticides (OPs): By using solid-phase extraction (SPE) with SWNT-Zn-modified glassy carbon electrode, the detection limit of methyl parathion (MP) is 2.3?ng?mL(-1).
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Regiodivergent synthesis of functionalized indene derivatives via Pt-catalyzed Rautenstrauch reaction of propargyl carbonates.
Org. Lett.
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A regiodivergent synthesis of functionalized indene derivatives from a Pt-catalyzed Rautenstrauch reaction of propargyl carbonate is described. A one-pot Rautenstrauch/Tsuji-Trost reaction delivering 2-indanones was realized efficiently using this methodology.
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Synthesis of imidazo[4,5-b]pyridines and imidazo[4,5-b]pyrazines by palladium catalyzed amidation of 2-chloro-3-amino-heterocycles.
Org. Lett.
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A facile synthesis of imidazo[4,5-b]pyridines and -pyrazines is described using a Pd-catalyzed amide coupling reaction. This reaction provides quick access to products with substitution at N1 and C2. A model system relevant to the natural product pentosidine has been demonstrated, as well as the total synthesis of the mutagen 1-Me-5-PhIP.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.