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Find video protocols related to scientific articles indexed in Pubmed.
High interfacial storage capability of porous NiMn2O4/C hierarchical tremella-like nanostructures as the lithium ion battery anode.
Nanoscale
PUBLISHED: 11-20-2014
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Porous hierarchical NiMn2O4/C tremella-like nanostructures are obtained through a simple solvothermal and calcination method. As the anode of lithium ion batteries (LIBs), porous NiMn2O4/C nanostructures exhibit a superior specific capacity and an excellent long-term cycling performance even at a high current density. The discharge capacity can stabilize at 2130 mA h g(-1) within 350 cycles at a current density of 1000 mA g(-1). After a long-term cycling of 1500 cycles, the capacity is still as high as 1773 mA h g(-1) at a high current density of 4000 mA g(-1), which is almost five times higher than the theoretical capacity of graphite. The porous NiMn2O4/C hierarchical nanostructure provides sufficient contact with the electrolyte and fast three-dimensional Li(+) diffusion channels, and dramatically improves the capacity of NiMn2O4/C via interfacial storage.
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Carbon Nanoparticles based Ratiometric Fluorescent Sensor for Detecting Mercury Ions in Aqueous Media and Living Cells.
ACS Appl Mater Interfaces
PUBLISHED: 11-14-2014
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A novel nanohybrid ratiometric fluorescence sensor is developed for selective detection of mercuric ions (Hg2+) and the application has been successfully demonstrated in HEPES buffer solution, lake water and living cells. The sensor is comprised of water soluble fluorescent carbon nanoparticles (CNPs) and Rhodamine B (RhB) and exhibits their corresponding dual emissions peaked at 437 and 575 nm, respectively, under a single excitation wavelength (350 nm). The photoluminescence of the CNPs in the nanohybrid system can be completely quenched by Hg2+ through effective electron or energy transfer process due to synergetic strong electrostatic interaction and metal-ligand coordination between the surface functional group of CNPs and Hg2+, while that of the RhB remains constant. This results in an obviously distinguishable fluorescence color variation (from violet to orange) of the nanohybrid solution. This novel sensor can effectively identify Hg2+ from other metal ions with relatively low background interference even in a complex system such as lake water. The detection limit of this method is as low as 42 nM. Furthermore, the sensing technique is applicable to detect Hg2+ in living cells.
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A bipolar transporter as an efficient green fluorescent emitter and host for red phosphors in multi- and single-layer organic light-emitting diodes.
Chemistry
PUBLISHED: 09-03-2014
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Multifunctional donor-acceptor compound 4,4'-bis(dibenzothiophene-S,S-dioxide-2-yl)triphenylamine (DSTPA) was obtained by linking a strongly electron-withdrawing core and a strongly electron-donating core with a biphenyl bridge in linear spatial alignment. DSTPA not only has suitable HOMO and LUMO levels for easily accepting both holes and electrons, it was also demonstrated to have a high fluorescence quantum yield of 0.98 and a high triplet energy level of 2.39?eV. Versatile applications of DSTPA for bipolar transport, green fluorescent emission, and sensitizing a red phosphor were systematically investigated in a series of multi- and single-layer organic light-emitting devices. In traditional multilayer devices, it shows excellent performance both in an undoped fluorescent device (used as a green emitter and achieving maximum current and power efficiencies (CE and PE) of 12.6?cd?A(-1) and 9.4?Lm?W(-1) , respectively) and in a red phosphorescent device (used as a host and achieving maximum CE and PE of 26.4?cd?A(-1) and 26.3?Lm?W(-1) , respectively). Furthermore, DSTPA was also simultaneously used as an emitter, a hole transporter, and an electron transporter in a single-layer device showing CE and PE of 5.1?cd?A(-1) and 4.7?Lm?W(-1) , respectively. A single-layer red phosphorescent device with efficiencies of 11.7?cd?A(-1) and 12.6?Lm?W(-1) was obtained by doping DSTPA with a red phosphor. The performances of all of the devices in this work are comparable to the best of their corresponding classes in the literature.
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Phase conversion from hexagonal CuS(y)Se(1-y) to cubic Cu(2-x)S(y)Se(1-y): composition variation, morphology evolution, optical tuning, and solar cell applications.
ACS Appl Mater Interfaces
PUBLISHED: 09-03-2014
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In this work, we report a simple and low-temperature approach for the controllable synthesis of ternary Cu-S-Se alloys featuring tunable crystal structures, compositions, morphologies, and optical properties. Hexagonal CuS(y)Se(1-y) nanoplates and face centered cubic (fcc) Cu(2-x)S(y)Se(1-y) single-crystal-like stacked nanoplate assemblies are synthesized, and their phase conversion mechanism is well investigated. It is found that both copper content and chalcogen composition (S/Se atomic ratio) of the Cu-S-Se alloys are tunable during the phase conversion process. Formation of the unique single-crystal-like stacked nanoplate assemblies is resulted from oriented stacking coupled with the Ostwald ripening effect. Remarkably, optical tuning for continuous red shifts of both the band-gap absorption and the near-infrared localized surface plasmon resonance are achieved. Furthermore, the novel Cu-S-Se alloys are utilized for the first time as highly efficient counter electrodes (CEs) in quantum dot sensitized solar cells (QDSSCs), showing outstanding electrocatalytic activity for polysulfide electrolyte regeneration and yielding a 135% enhancement in power conversion efficiency (PCE) as compared to the noble metal Pt counter electrode.
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Micro- and Nanotechnologies for Intracellular Delivery.
Small
PUBLISHED: 08-28-2014
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The majority of drugs and biomolecules need to be delivered into cells to be effective. However, the cell membranes, a biological barrier, strictly resist drugs or biomolecules entering cells, resulting in significantly reduced intracellular delivery efficiency. To overcome this barrier, a variety of intracellular delivery approaches including chemical and physical ways have been developed in recent years. In this review, the focus is on summarizing the nanomaterial routes involved in making use of a collection of receptors for the targeted delivery of drugs and biomolecules and the physical ways of applying micro- and nanotechnologies for high-throughput intracellular delivery.
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Comparing HbA1c, fasting and 2-h plasma glucose for screening for abnormal glucose regulation in patients undergoing coronary angiography.
Clin. Chem. Lab. Med.
PUBLISHED: 08-27-2014
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Abstract Background: We aimed to investigate the prevalence of undiagnosed abnormal glucose regulation (AGR, including diabetes and prediabetes) in patients undergoing coronary angiography (CAG) by using both glycated hemoglobin (HbA1c) and oral glucose tolerance test (OGTT) to screen, and to compare the performance of fasting plasma glucose (FPG), 2-h plasma glucose (2hPG), and HbA1c for screening for AGR. Methods: Eligible patients were adults without known diabetes who were admitted for CAG. Patients' glucose regulation status was defined by conducting HbA1c and OGTT 2-4 weeks after hospital discharge. The performance of FPG, 2hPG, and HbA1c for detecting AGR was evaluated using receiver operating characteristic (ROC) analysis. Results: A total of 689 subjects were included. According to OGTT, the prevalence rates of diabetes and prediabetes were 19.9% and 41.7%, respectively. The corresponding values were 28.0% and 60.4%, respectively, when HbA1c was adopted as a diagnostic criterion in addition to OGTT. For detecting diabetes, the area under the ROC curve (AUC) was higher for HbA1c than for FPG (0.87 vs. 0.80, p=0.005), but was not significantly different from that for 2hPG (0.87 vs. 0.88, p=0.58). For detecting AGR, the AUC was higher for HbA1c than for either FPG (0.94 vs. 0.74, p<0.001) or 2hPG (0.94 vs. 0.83, p<0.001). Conclusions: Using HbA1c and OGTT to screen, we reported an extremely high prevalence of previously undiagnosed AGR (28.0% diabetes and 60.4% prediabetes) in patients admitted for CAG. HbA1c may be adopted as an alternative to OGTT for screening for AGR in patients undergoing CAG.
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Insulinoma in a Young Female Patient with Systemic Lupus Erythematosus: A Case Report.
Endocr Pract
PUBLISHED: 08-22-2014
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Objective: Fasting hypoglycemia may occur in subjects with systemic lupus erythematosus (SLE) when accompanied with insulin-binding antibodies or insulin receptor antibodies. However, insulinoma has not been reported in SLE subjects with hypoglycemia.Methods: We present a case report and review the relevant literature.Results: A 26-year-old female with underlying SLE experienced several episodes of neuropsychiatric symptoms in a fasting state. The steroid dosage was titrated up, but in vain. Timely imaging studies showed a pancreatic tumor, and insulinoma was proven by pathology. Hypoglycemia did not recur after surgery.Conclusion: Physicians should distinguish insulinoma from autoimmunity-mediated hypoglycemia in SLE patients with fasting hypoglycemia.
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A graphene quantum dot photodynamic therapy agent with high singlet oxygen generation.
Nat Commun
PUBLISHED: 08-08-2014
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Clinical applications of current photodynamic therapy (PDT) agents are often limited by their low singlet oxygen ((1)O2) quantum yields, as well as by photobleaching and poor biocompatibility. Here we present a new PDT agent based on graphene quantum dots (GQDs) that can produce (1)O2 via a multistate sensitization process, resulting in a quantum yield of ~1.3, the highest reported for PDT agents. The GQDs also exhibit a broad absorption band spanning the UV region and the entire visible region and a strong deep-red emission. Through in vitro and in vivo studies, we demonstrate that GQDs can be used as PDT agents, simultaneously allowing imaging and providing a highly efficient cancer therapy. The present work may lead to a new generation of carbon-based nanomaterial PDT agents with overall performance superior to conventional agents in terms of (1)O2 quantum yield, water dispersibility, photo- and pH-stability, and biocompatibility.
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Core-Shell Si/C Nanospheres Embedded in Bubble Sheet-like Carbon Film with Enhanced Performance as Lithium Ion Battery Anodes.
Small
PUBLISHED: 07-15-2014
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Due to its high theoretical capacity and low lithium insertion voltage plateau, silicon has been considered one of the most promising anodes for high energy and high power density lithium ion batteries (LIBs). However, its rapid capacity degradation, mainly caused by huge volume changes during lithium insertion/extraction processes, remains a significant challenge to its practical application. Engineering Si anodes with abundant free spaces and stabilizing them by incorporating carbon materials has been found to be effective to address the above problems. Using sodium chloride (NaCl) as a template, bubble sheet-like carbon film supported core-shell Si/C composites are prepared for the first time by a facile magnesium thermal reduction/glucose carbonization process. The capacity retention achieves up to 93.6% (about 1018 mAh g(-1) ) after 200 cycles at 1 A g(-1) . The good performance is attributed to synergistic effects of the conductive carbon film and the hollow structure of the core-shell nanospheres, which provide an ideal conductive matrix and buffer spaces for respectively electron transfer and Si expansion during lithiation process. This unique structure decreases the charge transfer resistance and suppresses the cracking/pulverization of Si, leading to the enhanced cycling performance of bubble sheet-like composite.
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Design, synthesis, mechanisms of action, and toxicity of novel 20(s)-sulfonylamidine derivatives of camptothecin as potent antitumor agents.
J. Med. Chem.
PUBLISHED: 07-08-2014
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Twelve novel 20-sulfonylamidine derivatives (9a-9l) of camptothecin (1) were synthesized via a Cu-catalyzed three-component reaction. They showed similar or superior cytotoxicity compared with that of irinotecan (3) against A-549, DU-145, KB, and multidrug-resistant (MDR) KBvin tumor cell lines. Compound 9a demonstrated better cytotoxicity against MDR cells compared with that of 1 and 3. Mechanistically, 9a induced significant DNA damage by selectively inhibiting Topoisomerase (Topo) I and activating the ATM/Chk related DNA damage-response pathway. In xenograft models, 9a demonstrated significant activity without overt adverse effects at 5 and 10 mg/kg, comparable to 3 at 100 mg/kg. Notably, 9a at 300 mg/kg (i.p.) showed no overt toxicity in contrast to 1 (LD50 56.2 mg/kg, i.p.) and 3 (LD50 177.5 mg/kg, i.p.). Intact 9a inhibited Topo I activity in a cell-free assay in a manner similar to that of 1, confirming that 9a is a new class of Topo I inhibitor. 20-Sulfonylamidine 1-derivative 9a merits development as an anticancer clinical trial candidate.
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Physiological and biochemical characteristics of ethyl tiglate production pathway in the yeast Saprochaete suaveolens.
Yeast
PUBLISHED: 07-02-2014
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A yeast identified as Saprochaete suaveolens was investigated for its capacity to produce a large panel of flavouring molecules. With a production of 32 compounds including 28 esters, S. suaveolens seems to be a good producer of fruity flavours and fragrances and especially of unsaturated esters like ethyl tiglate. Physiological and biochemical analysis were performed in this study to provide metabolic route's comprehension of this compound. We show that the accumulation of ethyl tiglate by S. suaveolens is specifically induced by isoleucine. However, and contrary to S. cerevisiae which harbours a classical Ehrlich pathway leading to the production of 2-methylbutanol from isoleucine, our results provide phenotypic and enzymological evidences of ethyl tiglate biosynthesis in S. suaveolens through the catabolism of this amino acid by the ?-oxidation pathway, which generates tiglyl-CoA as probable intermediate. A kinetic analysis of this flavour molecule during growth of S. suaveolens on glucose and isoleucine showed a phase of production of ethyl tiglate that culminated concurrently with isoleucine exhaustion followed by a disappearance of this compound likely due to reassimilation by the yeast. Copyright © 2014 John Wiley & Sons, Ltd.
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Single crystalline wurtzite ZnO/zinc blende ZnS coaxial heterojunctions and hollow zinc blende ZnS nanotubes: synthesis, structural characterization and optical properties.
Nanoscale
PUBLISHED: 06-24-2014
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Synthesis of ZnO/ZnS heterostructures under thermodynamic conditions generally results in the wurtzite (WZ) structure of the ZnS component because its WZ phase is thermodynamically more stable than its zinc blende (ZB) phase. In this report, we demonstrate for the first time the preparation of ZnO/ZnS coaxial nanocables composed of single crystalline ZB structured ZnS epitaxially grown on WZ ZnO via a two-step thermal evaporation method. The deposition temperature is believed to play a crucial role in determining the crystalline phase of ZnS. Through a systematic structural analysis, the ZnO core and the ZnS shell are found to have an orientation relationship of (0002)ZnO(WZ)//(002)ZnS(ZB) and [01-10]ZnO(WZ)//[2-20]ZnS(ZB). Observation of the coaxial nanocables in cross-section reveals the formation of voids between the ZnO core and the ZnS shell during the coating process, which is probably associated with the nanoscale Kirkendall effect known to result in porosity. Furthermore, by immersing the ZnO/ZnS nanocable heterojunctions in an acetic acid solution to etch away the inner ZnO cores, single crystalline ZnS nanotubes orientated along the [001] direction of the ZB structure were also achieved for the first time. Finally, optical properties of the hollow ZnS tubes were investigated and discussed in detail. We believe that our study could provide some insights into the controlled fabrication of one dimensional (1D) semiconductors with desired morphology, structure and composition at the nanoscale, and the synthesized WZ ZnO/ZB ZnS nanocables as well as ZB ZnS nanotubes could be ideal candidates for the study of optoelectronics based on II-VI semiconductors.
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Synthesis of porous ZnS:Ag2S nanosheets by ion exchange for photocatalytic H2 generation.
ACS Appl Mater Interfaces
PUBLISHED: 06-09-2014
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ZnS:Ag2S porous nanostructures are prepared by a simple ion-exchange route using ZnS nanosheets as sacrificial templates. In solutions of different Ag ion concentrations, ZnS nanosheets are partially converted to Ag2S, resulting in porous ZnS:Ag2S nanosheet composites with different pore sizes. With the Ag2S nanocrystals playing the role of hole scavengers, the porous nanosheets exhibit a high photocatalytic H2 generation rate of 104.9 ?mol/h/g without using any noble metal cocatalyst.
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Achieving highly efficient simple-emission layer fluorescence/phosphorescence hybrid white organic light-emitting devices via effective confinement of triplets.
ACS Appl Mater Interfaces
PUBLISHED: 06-05-2014
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Achieving high efficiencies in simple device configurations is a long-standing and meaningful target for organic light-emitting devices (OLEDs). Herein, by utilizing an efficient blue-violet fluorophor (CzS1) that has a high triplet energy of 2.62 eV, the significance of effective confinement of the green triplets in fluorescence/phosphorescence hybrid white devices (F/P-WOLEDs) that have highly simplified emission layers (EMLs) containing only RGB emitters was demonstrated. The non-p-i-n warm-white device exhibited excellent performance with a maximum forward power efficiency high up to 42.1 lm W(-1), and maintaining at 26.3 lm W(1-) at a practical luminance of 1000 cd m(-2).
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Weight loss reduces serum monocyte chemoattractant protein-1 concentrations in association with improvements in renal injury in obese men with metabolic syndrome.
Clin. Chem. Lab. Med.
PUBLISHED: 05-01-2014
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Abstract Background: Monocyte chemoattractant protein-1 (MCP-1) is involved in obesity-related renal injury. The aim of the present study was to examine the effects of weight loss on changes in MCP-1 and markers of renal injury, specifically serum cystatin C (S-CysC) and urinary N-acetyl glucosaminidase (UNAG), in obese people. Methods: In this prospective study, 40 obese men with metabolic syndrome (MetS) participated in a 3-month dietary and exercise intervention. Twenty-eight subjects completed the study with a ?5% weight loss. Circulating MCP-1, S-CysC and UNAG to creatinine ratio (UNCR) were determined before and after the weight loss program. Results: Obesity-associated components of MetS demonstrated significant improvements after the weight loss program. In addition, at baseline, circulating MCP-1 concentrations were positively correlated with UNCR and S-CysC levels. After weight loss, blood MCP-1 and UNCR levels were significantly decreased, but S-CysC was not affected. Using multiple linear regression analysis, there was a significant relationship between changes in UNCR and MCP-1 after adjusting for other potential confounding factors. Conclusions: Weight loss may improve renal tubular injury by ameliorating obesity-related inflammation in obese men with MetS.
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Endoplasmic reticulum stress contributes to arsenic trioxide-induced intrinsic apoptosis in human umbilical and bone marrow mesenchymal stem cells.
Environ. Toxicol.
PUBLISHED: 04-22-2014
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Arsenic trioxide is an old drug and has been used for a long time in traditional Chinese and Western medicines. However, the cancer treatment of arsenic trioxide has heart and vascular toxicity. The cytotoxic effects of arsenic trioxide and its molecular mechanism in human umbilical mesenchymal stem cells (HUMSC) and human bone marrow-derived mesenchymal stem cells (HMSC-bm) were investigated in this study. Our results showed that arsenic trioxide significantly reduced the viability of HUMSC and HMSC-bm in a concentration- and time-dependent manner. Arsenic trioxide is able to induce apoptotic cell death in HUMSC and HMSC-bm, as shown from the results of morphological examination, flow cytometric analyses, DAPI staining and comet assay. The appearance of arsenic trioxide also led to an increase of intracellular free calcium (Ca(2+) ) concentration and the disruption of mitochondrial membrane potential (??m). The caspase-9 and caspase-3 activities were time-dependently increased in arsenic trioxide-treated HUMSC and HMSC-bm. In addition, the proteomic analysis and DNA microarray were carried out to investigate the expression level changes of genes and proteins affected by arsenic trioxide treatment in HUMSC. Our results suggest that arsenic trioxide induces a prompt induction of ER stress and mitochondria-modulated apoptosis in HUMSC and HMSC-bm. A framework was proposed for the effect of arsenic trioxide cytotoxicity by targeting ER stress. © 2014 Wiley Periodicals, Inc. Environ Toxicol, 2014.
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Synthesis of Honeycomb-like Mesoporous Pyrite FeS2 Microspheres as Efficient Counter Electrode in Quantum Dots Sensitized Solar Cells.
Small
PUBLISHED: 04-21-2014
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Honeycomb-like mesoporous pyrite FeS2 microspheres, with diameters of 500-800 nm and pore sizes of 25-30 nm, are synthesized by a simple solvothermal approach. The mesoporous FeS2 microspheres are demonstrated to be an outstanding counter electrode (CE) material in quantum dot sensitized solar cells (QDSSCs) for electrocatalyzing polysulfide electrolyte regeneration. The cell using mesoporous FeS2 microspheres as CE shows 86.6% enhancement in power conversion efficiency (PCE) than the cell using traditional noble Pt CE. Furthermore, it also shows 11.4% enhancement in PCE than the cell using solid FeS2 microspheres as CE, due to the mesoporous structure facilitating better contact with polysulfide electrolyte and fast diffusion of redox couple species in electrolyte.
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Porous CuCo2O4 nanocubes wrapped by reduced graphene oxide as high-performance lithium-ion battery anodes.
Nanoscale
PUBLISHED: 04-17-2014
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A composite of porous CuCo2O4 nanocubes well wrapped by reduced graphene oxide (rGO) sheets has been synthesized by a facile microwave-assisted solvothermal reaction and applied as anode in lithium ion batteries (LIBs). The porous structure of the CuCo2O4 nanocubes not only provides a high surface area for contact with the electrolyte, but also assists by accommodating volume change upon charging-discharging. Impedance measurements and transmission electron microscopy show that incorporation of rGO further decreases the charge transfer resistance and improves the structural stability of the composite. As an anode material for a LIB, the composite exhibits a high stable capacity of ? 570 mA h g(-1) at a current density of 1000 mA g(-1) after 350 cycles. With a high specific surface area and a low charge transfer resistance, the composite anode shows impressive performance especially at high current density. The LIB shows a high capacity of ? 450 mA h g(-1) even at a high current density of 5000 mA g(-1), demonstrating the composite's potential for applications in LIBs with long cycling life and high power density.
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Quinazoline analog HMJ-30 inhibits angiogenesis: involvement of endothelial cell apoptosis through ROS-JNK-mediated death receptor 5 signaling.
Oncol. Rep.
PUBLISHED: 03-26-2014
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The aim of the present study was to explore the effect of 6-fluoro-2-(3-fluorophenyl)-4-(cyanoanilino) quinazoline (HMJ-30) on the anti-angiogenic properties and apoptosis-related mechanism of human umbilical vein endothelial cells (HUVECs). In this study, HMJ-30 dose- and time-dependently inhibited the viability of HUVECs. We also found that HMJ-30 enhanced disruption of tube-like structures and suppressed cell migration in HUVECs after vascular endothelial growth factor (VEGF) induction. HMJ-30 was also observed to inhibit vessel branching and sprouting in chicken chorioallantoic membrane (CAM). Microsprouting induced by VEGF in the rat aortic ring and blood vessel formation in a mouse Matrigel plug were individually suppressed by HMJ-30. In an in vitro study, HMJ-30 induced the apoptotic death of HUVECs as indicated by DNA fragmentation and promoted reactive oxygen species (ROS) production as determined by flow cytometric assay. In addition, extrinsic caspase signaling (caspase-8 and -3) was activated in the HMJ-30-treated HUVECs and their inhibitors were applied to assess the signal transduction. We investigated the upstream of the death receptor pathway and further observed that the levels of death receptor 5 (DR5) and phosphorylated c-Jun N-terminal kinase (JNK) signals were upregulated in HUVECs following HMJ-30 challenge, which was confirmed by a JNK-specific inhibitor (SP600125). Hence, HMJ-30-induced endothelial cell apoptosis involved the ROS/JNK-regulated DR5 pathway. In summary, HMJ-30 may provide a potential therapeutic effect for the anti-vascular targeting of angiogenesis during cancer treatment.
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Si nanowire directly grown on a liquid metal substrate--towards wafer scale transferable nanowire arrays with improved visible-light sterilization.
Nanotechnology
PUBLISHED: 03-12-2014
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Integrating vertically aligned nanowires (NWs) on a functional substrate is important for the application of NWs in wafer scale assemblies and functional devices. However, vertically aligned NWs via the current epitaxial growth route can only be prepared on crystalline wafers. A convenient method is thus presented to overcome NW substrate limitations. Liquid metal is proposed to serve as a substrate for the initial growth of vertically aligned NWs. NWs could then be harvested from the growth substrate and integrated with functional substrates. Fabricated vertically aligned silicon NWs (SiNWs) were grown on molten Sn and then integrated into a flexible transparent poly(dimethylsiloxane) film to obtain a SiNW/functional substrate device. The device showed enhanced visible-light absorption ability and refreshable visible-light bactericidal activities with a bacterial reduction rate of close to 100%, indicating that growth with molten metal as a substrate could be a promising approach for extending the function and application of NWs.
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Ethanol extract of Hedyotis diffusa willd upregulates G0/G1 phase arrest and induces apoptosis in human leukemia cells by modulating caspase cascade signaling and altering associated genes expression was assayed by cDNA microarray.
Environ. Toxicol.
PUBLISHED: 03-11-2014
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The authors' previous study has shown that water extract of Hedyotis diffusa Willd (HDW) promoted immune response and exhibited anti-leukemic activity in BALB/c leukemic mice in vivo. In this study, the anti-proliferation effects of ethanol extract of H. diffusa Willd (EEHDW) on lung cancer cell lines (A549, H1355, and LLC), leukemia cell lines (HL-60, WEHI-3), and a mouse melanoma cell line (B16F10) in vitro were investigated. The results demonstrated that EEHDW suppressed the cell proliferation of A549, H1355, HL-60, WEHI-3, and B16F10 cells as well as reduced cell viability in a concentration-dependent manner. We found that EEHDW inhibited the cell proliferation of HL-60 cells in concentration-dependent manner. In addition, EEHDW triggered an arrest of HL-60 cells at G0/G1 phase and sub-G1 population (apoptotic cells). EEHDW provoked DNA condensation and DNA damage in HL-60 cells. The activities of caspase-3, caspase-8, and caspase-9 were elevated in EEHDW-treated HL-60 cells. DNA microarray to investigate and display the gene levels related to cell growth, signal transduction, apoptosis, cell adhesion, cell cycle, DNA damage and repair, transcription and translation was also used. These findings suggest that EEHDW may be a potential herbal medicine and therapeutic agent for the treatment of leukemia. © 2014 Wiley Periodicals, Inc. Environ Toxicol, 2014.
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The novel pterostilbene derivative ANK-199 induces autophagic cell death through regulating PI3 kinase class III/beclin 1/Atg?related proteins in cisplatin?resistant CAR human oral cancer cells.
Int. J. Oncol.
PUBLISHED: 03-06-2014
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Pterostilbene is an effective chemopreventive agent against multiple types of cancer cells. A novel pterostilbene derivative, ANK-199, was designed and synthesized by our group. Its antitumor activity and mechanism in cisplatin-resistant CAR human oral cancer cells were investigated in this study. Our results show that ANK-199 has an extremely low toxicity in normal oral cell lines. The formation of autophagic vacuoles and acidic vesicular organelles (AVOs) was observed in the ANK-199-treated CAR cells by monodansylcadaverine (MDC) and acridine orange (AO) staining, suggesting that ANK-199 is able to induce autophagic cell death in CAR cells. Neither DNA fragmentation nor DNA condensation was observed, which means that ANK-199-induced cell death is not triggered by apoptosis. In accordance with morphological observation, 3-MA, a specific inhibitor of PI3K kinase class III, can inhibit the autophagic vesicle formation induced by ANK-199. In addition, ANK-199 is also able to enhance the protein levels of autophagic proteins, Atg complex, beclin 1, PI3K class III and LC3-II, and mRNA expression of autophagic genes Atg7, Atg12, beclin 1 and LC3-II in the ANK-199-treated CAR cells. A molecular signaling pathway induced by ANK-199 was therefore summarized. Results presented in this study show that ANK-199 may become a novel therapeutic reagent for the treatment of oral cancer in the near future (patent pending).
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Charge-transfer complexes and their role in exciplex emission and near-infrared photovoltaics.
Adv. Mater. Weinheim
PUBLISHED: 02-05-2014
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Charge transfer and interactions at organic heterojunctions (OHJs) are known to have critical influences on various properties of organic electronic devices. In this Research News article, a short review is given from the electronic viewpoint on how the local molecular interactions and interfacial energetics at P/N OHJs contribute to the recombination/dissociation of electron-hole pairs. Very often, the P-type materials donate electrons to the N-type materials, giving rise to charge-transfer complexes (CTCs) with a P(?+) -N(?-) configuration. A recently observed opposite charge-transfer direction in OHJs is also discussed (i.e., N-type material donates electrons to P-type material to form P(?-) -N(?+) ). Recent studies on the electronic structures of CTC-forming material pairs are also summarized. The formation of P(?-) -N(?+) -type CTCs and their correlations with exciplex emission are examined. Furthermore, the potential applications of CTCs in NIR photovoltaic devices are reviewed.
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Energy-band engineering for tunable memory characteristics through controlled doping of reduced graphene oxide.
ACS Nano
PUBLISHED: 01-30-2014
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Tunable memory characteristics are used in multioperational mode circuits where memory cells with various functionalities are needed in one combined device. It is always a challenge to obtain control over threshold voltage for multimode operation. On this regard, we use a strategy of shifting the work function of reduced graphene oxide (rGO) in a controlled manner through doping gold chloride (AuCl3) and obtained a gradient increase of rGO work function. By inserting doped rGO as floating gate, a controlled threshold voltage (Vth) shift has been achieved in both p- and n-type low voltage flexible memory devices with large memory window (up to 4 times for p-type and 8 times for n-type memory devices) in comparison with pristine rGO floating gate memory devices. By proper energy band engineering, we demonstrated a flexible floating gate memory device with larger memory window and controlled threshold voltage shifts.
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Highly efficient orange and warm white phosphorescent OLEDs based on a host material with a carbazole-fluorenyl hybrid.
Chem Asian J
PUBLISHED: 01-28-2014
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A new carbazole-fluorenyl hybrid compound, 3,3'(2,7-di(naphthaline-2-yl)-9H-fluorene-9,9-diyl)bis(9-phenyl-9H-carbazole) (NFBC) was synthesized and characterized. The compound exhibits blue-violet emission both in solution and in film, with peaks centered at 404 and 420?nm. In addition to the application as a blue emitter, NFBC is demonstrated to be a good host for phosphorescent dopants. By doping Ir(2-phq)3 in NFBC, a highly efficient orange organic light-emitting diode (OLED) with a maximum efficiency of 32?cd?A(-1) (26.5?Lm?W(-1)) was obtained. Unlike most phosphorescent OLEDs, the device prepared in our study shows little efficiency roll-off at high brightness and maintains current efficiencies of 31.9 and 26.8?cd?A(-1) at a luminance of 1000 and 10,000?cd?m(-2), respectively. By using NFBC simultaneously as a blue fluorescence emitter and as a host for a phosphorescent dopant, a warm white OLED with a maximum efficiency of 22.9?Lm?W(-1) (21.9?cd?A(-1)) was also obtained.
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Cell death caused by quinazolinone HMJ-38 challenge in oral carcinoma CAL 27 cells: dissections of endoplasmic reticulum stress, mitochondrial dysfunction and tumor xenografts.
Biochim. Biophys. Acta
PUBLISHED: 01-26-2014
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This investigation clearly clarified the synthesized and antimitotic compound, 2-(3'-methoxyphenyl)-6-pyrrolidinyl-4-quinazolinone (HMJ-38), addressing its target and precise mechanism of action. We hypothesized that HMJ-38 might sensitize apoptotic death of human oral carcinoma CAL 27 cells in vitro and inhibit xenograft tumor growth in vivo.
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Surface engineering of ZnO nanostructures for semiconductor-sensitized solar cells.
Adv. Mater. Weinheim
PUBLISHED: 01-25-2014
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Semiconductor-sensitized solar cells (SSCs) are emerging as promising devices for achieving efficient and low-cost solar-energy conversion. The recent progress in the development of ZnO-nanostructure-based SSCs is reviewed here, and the key issues for their efficiency improvement, such as enhancing light harvesting and increasing carrier generation, separation, and collection, are highlighted from aspects of surface-engineering techniques. The impact of other factors such as electrolyte and counter electrodes on the photovoltaic performance is also addressed. The current challenges and perspectives for the further advance of ZnO-based SSCs are discussed.
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A multifunctional phosphine oxide-diphenylamine hybrid compound as a high performance deep-blue fluorescent emitter and green phosphorescent host.
Chem. Commun. (Camb.)
PUBLISHED: 01-14-2014
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A novel phosphine oxide-diphenylamine hybrid compound POA was designed and synthesized with the aim of developing new multifunctional blue fluorophores. POA is the first kind of compound that can be used as a high-efficiency deep-blue emitter (5.4% EQE) and a host to fabricate high-performance green phosphorescent OLEDs (18.1% EQE).
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Diallyl trisulfide inhibits migration, invasion and angiogenesis of human colon cancer HT-29 cells and umbilical vein endothelial cells, and suppresses murine xenograft tumour growth.
J. Cell. Mol. Med.
PUBLISHED: 01-07-2014
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Angiogenesis inhibitors are beneficial for the prevention and treatment of angiogenesis-dependent diseases including cancer. We examined the cytotoxic, anti-metastatic, anti-cancer and anti-angiogenic effects of diallyl trisulfide (DATS). In HT29 cells, DATS inhibited migration and invasion through the inhibition of focal adhesion kinase (FAK), extracellular signal-regulated kinase, c-Jun N-terminal kinase and p38 which was associated with inhibition of matrix metalloproteinases-2, -7 and -9 and VEGF. In human umbilical vein endothelial cells (HUVEC), DATS inhibited the migration and angiogenesis through FAK, Src and Ras. DATS also inhibited the secretion of VEGF. The capillary-like tube structure formation and migration by HUVEC was inhibited by DATS. The chicken egg chorioallantoic membrane (CAM) assay indicated that DATS treatment inhibited ex-vivo angiogenesis. We investigated the anti-tumour effects of DATS against human colon cancer xenografts in BALB/c(nu/nu) mice and its anti-angiogenic activity in vivo. In this in-vivo study, DATS also inhibited the tumour growth, tumour weight and angiogenesis (decreased the levels of haemoglobin) in HT29 cells. In conclusion, the present results suggest that the inhibition of angiogenesis may be an important mechanism in colon cancer chemotherapy by DATS.
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Correlation between reduction of superior interventricular groove epicardial fat thickness and improvement of insulin resistance after weight loss in obese men.
Diabetol Metab Syndr
PUBLISHED: 01-01-2014
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It has been recognized that reduction of abdominal visceral fat and subcutaneous fat are associated with improvement in insulin-resistance (IR) after weight loss. However, few studies have investigated the correlation of reduction in epicardial adipose tissue (EAT) with improvement of IR index after weight loss in obese non-diabetic men with metabolic syndrome (MetS).
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Post-meal ?-cell function predicts the efficacy of glycemic control in patients with type 2 diabetes inadequately controlled by metformin monotherapy after addition of glibenclamide or acarbose.
Diabetol Metab Syndr
PUBLISHED: 01-01-2014
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This study aimed to explore parameters which will predict good control of HbA1c after adding a second anti-diabetic drug in patients with type 2 diabetes mellitus (T2DM) inadequately controlled with metformin monotherapy.
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Near-infrared fluorescence imaging using organic dye nanoparticles.
Biomaterials
PUBLISHED: 01-01-2014
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Near-infrared (NIR) fluorescence imaging in the 700-1000 nm wavelength range has been very attractive for early detection of cancers. Conventional NIR dyes often suffer from limitation of low brightness due to self-quenching, insufficient photo- and bioenvironmental stability, and small Stokes shift. Herein, we present a strategy of using small-molecule organic dye nanoparticles (ONPs) to encapsulate NIR dyes to enable efficient fluorescence resonance energy transfer to obtain NIR probes with remarkably enhanced performance for in vitro and in vivo imaging. In our design, host ONPs are used as not only carriers to trap and stabilize NIR dyes, but also light-harvesting agent to transfer energy to NIR dyes to enhance their brightness. In comparison with pure NIR dyes, our organic dye nanoparticles possess almost 50-fold increased brightness, large Stokes shifts (?250 nm) and dramatically enhanced photostability. With surface modification, these NIR-emissive organic nanoparticles have water-dispersity and size- and fluorescence- stability over pH values from 2 to 10 for almost 60 days. With these superior advantages, these NIR-emissive organic nanoparticles can be used for highly efficient folic-acid aided specific targeting in vivo and ex vivo cellular imaging. Finally, during in vivo imaging, the nanoparticles show negligible toxicity. Overall, the results clearly display a potential application of using the NIR-emissive organic nanoparticles for in vitro and in vivo imaging.
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Allyl isothiocyanate inhibits cell metastasis through suppression of the MAPK pathways in epidermal growth factor?stimulated HT29 human colorectal adenocarcinoma cells.
Oncol. Rep.
PUBLISHED: 09-14-2013
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Allyl isothiocyanate (AITC) has been found to present sources from consumed cruciferous vegetables. AITC is known to possess pharmacological and anticancer activities. The present study was designed to test the hypothesis that AITC suppressed the invasion and migration of epidermal growth factor (EGF)-stimulated HT29 cells and to elucidate the mechanisms for the antimetastatic abilities in vitro. The invasion and migration of EGF-stimulated HT29 cells were determined individually by Transwell cell invasion and wound-healing assays. Our results showed that AITC effectively inhibited both the invasive and migratory ability of HT29 cells. Furthermore, AITC downregulated the protein levels of matrix metalloproteinase-2 (MMP-2), MMP-9 and mitogen-activated protein kinases (MAPKs) (p-JNK, p-ERK and p-p38) by western blot analysis in HT29 cells following EGF induction. Thus, the metastatic responses in AITC-treated HT29 cells after EGF stimulation were mediated by the MMP-2/-9 and MAPK signaling pathways. We also used gene expression microarrays to investigate the gene levels related to cell growth, G-protein coupled receptor, angiogenesis, cell adhesion, cell cycle and mitosis, cell migration, cytoskeleton organization, DNA damage and repair, transcription and translation, EGFR and PKB/mTOR signals. In summary, it is possible that AITC suppresses the invasion and migration of EGF-induced HT29 cells, resulting from MMP-2/-9 and MAPKs. Hence, AITC may be beneficial in the treatment of human colorectal adenocarcinoma in the future.
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Oral administration of benzyl-isothiocyanate inhibits in vivo growth of subcutaneous xenograft tumors of human malignant melanoma A375.S2 cells.
In Vivo
PUBLISHED: 08-31-2013
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A number of experiments have demonstrated that benzyl-isothiocyanate (BITC) induces cytotoxic cell death through the induction of apoptosis in various human cancer cell lines. In the present study, we investigated the effects of BITC on the growth of A375.S2 cell xenograft tumors in nude BALB/c mice in vivo. The A375.S2 cancer cells were inoculated subcutaneously into the lower flanks of each nude mouse. After cancer cell inoculation, all animals were maintained in the animal room for seven days and all mice produced one palpable tumor. Animals were randomly divided into two groups, each mouse was individually given intraperitoneal injections of BITC (20 mg/kg) or not (control). Results from the in vivo experiments indicated that BITC did not significantly affect the body weight of nude BALB/c mice bearing xenograft A375.S2 cell tumors but did significantly decrease the tumor weight.
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Curcumin-loaded nanoparticles enhance apoptotic cell death of U2OS human osteosarcoma cells through the Akt-Bad signaling pathway.
Int. J. Oncol.
PUBLISHED: 08-23-2013
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Curcumin has potential anticancer activity and has been shown to be involved in several signaling pathways including differentiation and apoptosis. Our previous study showed that water-soluble PLGA curcumin nanoparticles (Cur-NPs) triggered apoptotic cell death through regulation of the function of MDR1 and the production of reactive oxygen species (ROS) in cisplatin-resistant human oral cancer CAR cells. In this study, we investigated the anti-proliferative effects of Cur-NPs on human osteosarcoma U2OS cells. The morphology of Cur-NPs showed spherical shape by TEM analysis. The encapsulation efficiency of curcumin in Cur-NPs prepared by single emulsion was 90.5±3.0%. Our results demonstrated that the curcumin fragments on the mass spectrum of Cur-NPs and the peaks of curcumin standard could be found on the Cur-NPs spectrum by 1H-NMR spectra analysis. Cur-NPs induced anti-proliferative effects and apoptosis in U2OS cells. Compared to the untreated U2OS cells, more detectable amount of Cur-NPs was found inside the treated U2OS cells. Cur-NPs induced DNA fragmentation and apoptotic bodies in U2OS cells. Both the activity and the expression levels of caspases-3/-7 and caspase-9 were elevated in the treated U2OS cells. Cur-NPs upregulated the protein expression levels of cleaved caspase-3/caspase-9, cytochrome c, Apaf-1 and Bad and downregulated the protein expression level of p-Akt in U2OS cells. These results suggest Cur-NPs are effective in enhancing apoptosis in human osteosarcoma cells and thus could provide potential for cancer therapeutics.
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Silicon nanowire based single-molecule SERS sensor.
Nanoscale
PUBLISHED: 07-30-2013
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One-dimensional nanowire (NW) optical sensors have attracted great attention as promising nanoscale tools for applications such as probing inside living cells. However, achieving single molecule detection on NW sensors remains an interesting and unsolved problem. In the present paper, we investigate single-molecule detection (SMD) on a single SiNW based surface-enhanced Raman scattering (SERS) sensor, fabricated by controllably depositing silver nanoparticles on a SiNW (AgNP-SiNW). Both Raman spectral blinking and bi-analyte approaches are performed in aqueous solution to investigate SMD on individual SiNW SERS sensors. The results extend the functions of the SiNW sensor to SMD and provide insight into the molecule level illustration on the sensing mechanism of the nanowire sensor.
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Water-Dispersible, pH-Stable and Highly-Luminescent Organic Dye Nanoparticles with Amplified Emissions for In Vitro and In Vivo Bioimaging.
Small
PUBLISHED: 07-22-2013
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A new strategy is presented for using doped small-molecule organic nanoparticles (NPs) to achieve high-performance fluorescent probes with strong brightness, large Stokes shifts and tunable emissions for in vitro and in vivo imaging. The host organic NPs are used not only as carriers to encapsulate different doped dyes, but also as fluorescence resonance energy transfer donors to couple with the doped dyes (as acceptors) to achieve multicolor luminescence with amplified emissions (AE). The resulting optimum green emitting NPs show high brightness with quantum yield (QY) of up to 45% and AE of 12 times; and the red emitting NPs show QY of 14% and AE of 10 times. These highly-luminescent doped NPs can be further surface modified with poly(maleic anhydride-alt-1-octadecene)-polyethylene glycol (C18PMH-PEG), endowing them with excellent water dispersibility and robust stability in various bio-environments covering wide pH values from 2 to 10. In this study, cytotoxicity studies and folic acid targeted cellular imaging of these multicolor probes are carried out to demonstrate their potential for in vitro imaging. On this basis, applications of the NP probes in in vivo and ex vivo imaging are also investigated. Intense fluorescent signals of the doped NPs are distinctly, selectively and spatially resolved in tumor sites with high sensitivity, due to the preferential accumulation of the NPs in tumor sites through the passive enhanced permeability and retention effect. The results clearly indicate that these doped NPs are promising fluorescent probes for biomedical applications.
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Low-cost solar cell based on a composite of silicon nanowires and a highly conductive nonphotoactive polymer.
Chemistry
PUBLISHED: 07-12-2013
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Hybrid bulk heterojunction solar cells based on inorganic-nanowire (NW)/conjugated-polymer composites have been shown to achieve a power conversion efficiency (PCE) of 1-3?%, which is much lower than theoretically expected. This work addresses the short exciton diffusion lengths in common photoactive polymers with a new solar-cell design that has a PCE of 4.68?% (see scheme; ITO=indium tin oxide, G-PEDOT:PSS=glycerol-doped poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate); E=electropolymerized; a=amorphous).
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The novel synthetic compound 6-acetyl-9-(3,4,5-trimetho-xybenzyl)-9H-pyrido[2,3-b]indole induces mitotic arrest and apoptosis in human COLO 205 cells.
Int. J. Oncol.
PUBLISHED: 07-05-2013
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A novel synthetic compound 6-acetyl-9-(3,4,5-trimetho-xybenzyl)-9H-pyrido[2,3-b]indole (HAC-Y6) demonstrated selective anticancer activity. In the present study, COLO 205 cells were treated with HAC-Y6 to investigate the molecular mechanisms underlying its effects. HAC-Y6 induced growth inhibition, G2/M arrest and apoptosis in COLO 205 cells with an IC50 of 0.52±0.035 µM. Annexin V/PI double staining demonstrated the presence of apoptotic cells. JC-1 staining analysis showed that HAC-Y6 decreased mitochondrial membrane potential in support of apoptosis. An immunostaining assay revealed that HAC-Y6 depolymerized microtubules. Treatment of COLO 205 cells with HAC-Y6 resulted in increased expression of BubR1 and cyclin B1 and decreased expression of aurora A, phospho-aurora A, aurora B, phospho-aurora B and phospho-H3. HAC-Y6 treatment increased protein levels of active caspase-3, caspase-9, Endo G, AIF, Apaf-1, cytochrome c and Bax, but treatment with the compound caused reduced levels of procaspase-3, procaspase-9, Bcl-xL and Bcl-2. Overall, our results suggest that HAC-Y6 exerts anticancer effects by disrupting microtubule assembly and inducing G2/M arrest, polyploidy and apoptosis via mitochondrial pathways in COLO 205 cells.
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Dynamic and dual effects of glycated hemoglobin on estimated glomerular filtration rate in type 2 diabetic outpatients.
Am. J. Nephrol.
PUBLISHED: 06-25-2013
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Diabetic nephropathy is the leading cause of incident end-stage renal disease in Taiwan. Previous studies on the consistent benefits of glycemic control in diabetic nephropathy focused primarily on delaying microalbuminuria. However, this effect on glomerular filtration rate (GFR) remains controversial. This study aims to establish a model that explains the controversial effects of glycated hemoglobin (HbA1C) on GFR.
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Synthesis of In2O3-In2S3 core-shell nanorods with inverted type-I structure for photocatalytic H2 generation.
Phys Chem Chem Phys
PUBLISHED: 06-25-2013
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In2O3-In2S3 core-shell nanostructures were prepared via a simple hydrothermal process at low temperatures. Ultraviolet photoelectron spectroscopy (UPS) shows that the In2O3-In2S3 nanorod is an inverted type I nanostructure. The energy potential in this structure would drive both the photo-generated holes and electrons towards the shell to facilitate photocatalytic H2 generation. Such inverted type-I nanostructure is firstly used for hydrogen generation. Comparing with reported indium-based photocatalysts upon UV-Vis illumination, the core-shell In2O3-In2S3 nanostructure obtained here exhibits a good H2 evolution rate of 61.4 ?mol h(-1) g(-1).
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Acarbose plus metformin fixed-dose combination outperforms acarbose monotherapy for type 2 diabetes.
Diabetes Res. Clin. Pract.
PUBLISHED: 06-10-2013
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To compare the efficacy and safety of acarbose plus metformin fixed-dose combination (FDC) versus acarbose monotherapy for type 2 diabetes (T2D).
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Self-assembly and hierarchical patterning of aligned organic nanowire arrays by solvent evaporation on substrates with patterned wettability.
ACS Appl Mater Interfaces
PUBLISHED: 06-06-2013
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The controlled growth and alignment of one-dimensional organic nanostructures at well-defined locations considerably hinders the integration of nanostructures for electronic and optoelectronic applications. Here, we demonstrate a simple process to achieve the growth, alignment, and hierarchical patterning of organic nanowires on substrates with controlled patterns of surface wettability. The first-level pattern is confined by the substrate patterns of wettability. Organic nanostructures are preferentially grown on solvent wettable regions. The second-level pattern is the patterning of aligned organic nanowires deposited by controlling the shape and movement of the solution contact lines during evaporation on the wettable regions. This process is controlled by the cover-hat-controlled method or vertical evaportation method. Therefore, various new patterns of organic nanostructures can be obtained by combing these two levels of patterns. This simple method proves to be a general approach that can be applied to other organic nanostructure systems. Using the as-prepared patterned nanowire arrays, an optoelectronic device (photodetector) is easily fabricated. Hence, the proposed simple, large-scale, low-cost method of preparing patterns of highly ordered organic nanostructures has high potential applications in various electronic and optoelectronic devices.
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Curcumin-loaded nanoparticles induce apoptotic cell death through regulation of the function of MDR1 and reactive oxygen species in cisplatin-resistant CAR human oral cancer cells.
Int. J. Oncol.
PUBLISHED: 06-03-2013
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Curcumin is a polyphenolic compound which possesses anticancer potential. It has been shown to induce cell death in a variety of cancer cells, however, its effect on CAL27?cisplatin-resistant human oral cancer cells (CAR cells) has not been elucidated to date. The low water solubility of curcumin which leads to poor bioavailability, however, has been highlighted as a major limiting factor. In this study, we utilized water-soluble PLGA curcumin nanoparticles (Cur-NPs), and investigated the effects of Cur-NPs on CAR cells. The results showed Cur-NPs induced apoptosis in CAR cells but exhibited low cytotoxicity to normal human gingival fibroblasts (HGFs) and normal human oral keratinocytes (OKs). Cur-NPs triggered DNA concentration, fragmentation and subsequent apoptosis. Compared to untreated CAR cells, a more detectable amount of Calcein-AM accumulation was found inside the treated CAR cells. Cur-NPs suppressed the protein and mRNA expression levels of MDR1. Both the activity and the expression levels of caspase-3 and caspase-9 were elevated in the treated CAR cells. The Cur-NP-triggered apoptosis was blocked by specific inhibitors of pan-caspase (z-VAD-fmk), caspase-3 (z-DEVD-fmk), caspase-9 (z-LEHD-fmk) and antioxidant agent (N-acetylcysteine; NAC). Cur-NPs increased reactive oxygen species (ROS) production, upregulated the protein expression levels of cleaved caspase-3/caspase-9, cytochrome c, Apaf-1, AIF, Bax and downregulated the protein levels of Bcl-2. Our results suggest that Cur-NPs triggered the intrinsic apoptotic pathway through regulating the function of multiple drug resistance protein 1 (MDR1) and the production of reactive oxygen species (ROS) in CAR cells. Cur-NPs could be potentially efficacious in the treatment of cisplatin-resistant human oral cancer.
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Propofol induces DNA damage in mouse leukemic monocyte macrophage RAW264.7 cells.
Oncol. Rep.
PUBLISHED: 05-28-2013
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Propofol is one of the most widely clinically used intravenous anesthetic, and it induces apoptosis in human and murine leukemia cell lines. Yet, whether propofol causes DNA damage and affects the mRNA expression of repair-associated genes in cancer cells remains undetermined. In the present study, we investigated the effects of propofol on DNA damage and associated mRNA gene expression in RAW264.7 cells. Comet assay and DNA gel electrophoresis were used to evaluate DNA damage in RAW264.7 cells and propofol-inhibited cell growth in vitro. The results revealed a longer DNA tail and DNA fragmentation. Real-time PCR assay was used to examine mRNA gene expression of DNA damage and DNA repair-associated genes. Following exposure to propofol for 48 h, a decrease in the mRNA expression of DNA-PK, BRCA1, MGMT and p53 was noted in the RAW264.7 cells. Results from the western blotting indicated that p53, MGMT, 14-3-3-?, BRCA1 and MDC1 proteins were decreased while p-p53 and p-H2A.X(S140) were increased in the RAW264.7 cells following exposure to propofol. In conclusion, exposure to propofol caused DNA damage and inhibited mRNA expression and protein levels of repair-associated genes in RAW264.7 cells.
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Design, synthesis, and mechanism of action of 2-(3-hydroxy-5-methoxyphenyl)-6-pyrrolidinylquinolin-4-one as a potent anticancer lead.
Bioorg. Med. Chem. Lett.
PUBLISHED: 05-03-2013
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New 6- (or 6,7-) substituted 2-(hydroxyl substituted phenyl)quinolin-4-one derivatives were synthesized and screened for antiproliferative effects against cancer cell lines. Structure-activity relationship correlations were established and the most promising compound 2-(3-hydroxy-5-methoxyphenyl)-6-pyrrolidin-1-ylquinolin-4-one (6h) exhibited strong inhibitory activity against various human cancer cell lines, particularly non-small cell lung cancer NCI-H522. Additional studies suggested a mechanism of action resembling that of the antimitotic drug vincristine. The presence of a C-ring OH group in 6h will allow this compound to be converted readily to a water soluble and physicochemically stable hydrophilic prodrug. Compound 6h is proposed as a new anticancer lead compound.
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The effects of oxygen on controlling the number of carbon layers in the chemical vapor deposition of graphene on a nickel substrate.
Nanotechnology
PUBLISHED: 04-11-2013
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While oxygen is typically considered undesirable during the chemical vapor deposition (CVD) of graphene on metal substrates, we demonstrate that suitable amounts of oxygen in the CVD system can in fact improve the uniformity and thickness control of the graphene film. The role of oxygen on the CVD of graphene on a nickel substrate using a propylene precursor was investigated with various surface analytical techniques. It was found that the number of carbon layers in the deposited graphene sample decreases as the concentration of oxygen increases. In particular, single-layer graphene can be easily obtained with an oxygen/propylene ratio of 1/9. In the presence of oxygen, a thin layer of nickel oxide will form on the substrate. The oxide layer decreases the concentration of carbon atoms dissolved in the nickel substrate and results in graphene samples with a decreasing number of carbon layers.
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Phenethyl isothiocyanate suppresses EGF-stimulated SAS human oral squamous carcinoma cell invasion by targeting EGF receptor signaling.
Int. J. Oncol.
PUBLISHED: 03-03-2013
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Phenethyl isothiocyanate (PEITC) is a natural compound that is involved in chemoprevention as well as inhibition of cell growth and induction of apoptosis in several types of cancer cells. Previous studies have revealed that PEITC suppresses the invasion of AGS gastric and HT-29 colorectal cancer cells. However, the effects of PEITC on the metastasis of SAS oral cancer cells remain to be determined. Our results showed that PEITC treatment inhibited the invasion of EGF-stimulated SAS cells in a concentration-dependent manner, but appeared not to affect the cell viability. The expression and enzymatic activities of matrix metalloprotease-2 (MMP-2) and matrix metalloprotease-9 (MMP-9) were suppressed by PEITC. Concomitantly, we observed an increase in the protein expression of both tissue inhibitor of metalloproteinase-1 (TIMP-1) and -2 (TIMP-2) in treated cells. Furthermore, PEITC treatments decreased the protein phosphorylation of epidermal growth factor receptor (EGFR) and downstream signaling proteins including PDK1, PI3K (p85), AKT, phosphorylated IKK and I?B to inactivate NF-?B for the suppression of MMP-2 and MMP-9 expression. In addition, PEITC can trigger the MAPK signaling pathway through the increase in phosphorylated p38, JNK and ERK in treated cells. Our data indicate that PEITC is able to inhibit the invasion of EGF-stimulated SAS oral cancer cells by targeting EGFR and its downstream signaling molecules and finally lead to the reduced expression and enzymatic activities of both MMP-2 and MMP-9. These results suggest that PEITC is promising for the therapy of oral cancer metastasis.
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Trans-ethnic fine mapping identifies a novel independent locus at the 3 end of CDKAL1 and novel variants of several susceptibility loci for type 2 diabetes in a Han Chinese population.
Diabetologia
PUBLISHED: 02-27-2013
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Candidate gene and genome-wide association studies have identified ?60 susceptibility loci for type 2 diabetes. A majority of these loci have been discovered and tested only in European populations. The aim of this study was to assess the presence and extent of trans-ethnic effects of these loci in an East Asian population.
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Kaempferol suppresses cell metastasis via inhibition of the ERK-p38-JNK and AP-1 signaling pathways in U-2 OS human osteosarcoma cells.
Oncol. Rep.
PUBLISHED: 02-26-2013
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Kaempferol is a natural flavonoid that possesses anti-proliferative and apoptosis-inducing activities in several cancer cell lines. In the present study, we investigated the anti-metastatic activity of kaempferol and its molecular mechanism(s) of action in human osteosarcoma cells. Kaempferol displayed inhibitory effects on the invasion and adhesion of U-2 osteosarcoma (OS) cells in a concentration-dependent manner by Matrigel Transwell assay and cell adhesion assay. Kaempferol also inhibited the migration of U-2 OS cells in a concentration-dependent manner at different treatment time points by wound-healing assay. Additional experiments showed that kaempferol treatment reduced the enzymatic activities and protein levels of matrix metalloproteinase (MMP)-2, MMP-9 and urokinase plasminogen activator (uPA) by gelatin and casein-plasminogen zymography assays and western blot analyses. Kaempferol also downregulated the mRNA levels of MMP-2 and MMP-9 by quantitative PCR analyses. Furthermore, kaempferol was able to reduce the protein phosphorylation of ERK, p38 and JNK by western blotting. By electrophoretic mobility-shift assay (EMSA), we demonstrated that kaempferol decreased the DNA binding activity of AP-1, an action likely to result in the reduced expression of MMP-2, MMP-9 and uPA. Collectively, our data showed that kaempferol attenuated the MAPK signaling pathways including ERK, JNK and p38 and resulted in the decreased DNA binding ability of AP-1, and hence, the downregulation in the expression and enzymatic activities of MMP-2, MMP-9 and uPA, contributing to the inhibition of metastasis of U-2 OS cells. Our results suggest a potential role of kaempferol in the therapy of tumor metastasis of OS.
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Novel efficient blue fluorophors with small singlet-triplet splitting: hosts for highly efficient fluorescence and phosphorescence hybrid WOLEDs with simplified structure.
Adv. Mater. Weinheim
PUBLISHED: 02-18-2013
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The exact hosts for F-P hybrid WOLEDs have been first demonstrated following a new design strategy for blue fluorophors with small singlet-triplet splitting. Two novel compounds DPMC and DAPSF exhibit efficient blue fluorescence, high triplet energies and good conductivities. These merits allow us to use new simplified device designs to achieve high efficiency, slow efficiency roll-off and stable emission color.
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A versatile triphenylamine/fluoranthene-based derivative as a nondoped green-emitting, hole-transporting interlayer for electroluminescent devices.
Chem Asian J
PUBLISHED: 01-02-2013
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A new triphenylamine-bridged fluoranthene derivative, 4-(7,10-diphenylfluoranthen-8-yl)-N-[4-(7,10-diphenylfluoranthen-8-yl)phenyl]-N-phenylaniline (BDPFPA), with a high glass transition temperature of 220?°C has been synthesized and characterized. BDPFPA is a highly fluorescent and versatile material that can be used as a nondoped green emitter and as a hole transporter. BDPFPA was used in a standard trilayer device as the emitting layer, which showed a low turn-on voltage (<3?V) and a high efficiency of 11.6?cd?A(-1). The device also shows little efficiency roll-off at high brightness. For example, the efficiency can still be maintained at 11.4?cd? A(-1) (5.4?lm? W(-1)) at a brightness of 10,000?cd? m(-2). These results are among the best reported for nondoped fluorescent green organic light-emitting diodes. A simple bilayer device, in which BDPFPA serves as a hole-transporting layer, has a maximum power efficiency of 3.3?lm? W(-1) and the performance is nearly 40?% higher than that of an N,N-bis(1-naphthyl)-N,N- diphenyl-1,1-biphenyl-4,4-diamine (NPB)-based standard device.
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Bee venom induces apoptosis through intracellular Ca2+ -modulated intrinsic death pathway in human bladder cancer cells.
Int. J. Urol.
PUBLISHED: 12-11-2011
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To focus on bee venom-induced apoptosis in human bladder cancer TSGH-8301 cells and to investigate its signaling pathway to ascertain whether intracellular calcium iron (Ca(2+)) is involved in this effect.
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Mono-disperse silver quantum dots modified formvar film.
J Nanosci Nanotechnol
PUBLISHED: 11-22-2011
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Formvar films were treated with different doses of silver ions implantation. The implanted silver ions were found to form silver quantum dots (AgQDs) uniformly distributed in the formvar films. While density of the AgQDs increases as the implantation dose increases, their sizes are not sensitive to the dose. It was found that the formvar films implanted with AgQDs have excellent bacteria killing capability. The same implantation approach can also be extended for application in other matrices. As an example, ZnS nanoribbon was implanted with the same approach to obtain uniformly distributed AgQDs with monodispersed size.
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Effects of acarbose versus glibenclamide on glycemic excursion and oxidative stress in type 2 diabetic patients inadequately controlled by metformin: a 24-week, randomized, open-label, parallel-group comparison.
Clin Ther
PUBLISHED: 10-17-2011
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Glycemic excursion is significantly associated with oxidative stress, which plays a role in the development of chronic complications in type 2 diabetes mellitus (T2DM). Acarbose has been reported to reduce cardiovascular risk in patients with impaired glucose tolerance and T2DM. We hypothesize that treatment with acarbose could attenuate glycemic excursions and reduce oxidative stress in patients with T2DM.
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Butylated hydroxyanisole affects immunomodulation and promotes macrophage phagocytosis in normal BALB/c mice.
Mol Med Rep
PUBLISHED: 09-14-2011
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Butylated hydroxyanisole (BHA), a synthetic antioxidant, has been used in fat and fatty foods to prevent oxidative deterioration. However, the functions of BHA on immune responses in normal mice remain elusive. The aim of the present study was to investigate the effects of oral treatment of BHA on immune responses in normal mice in vivo. BALB/c mice received various treatments. Blood samples were collected and analyzed. Flow cytometry was used to determine the levels of the cell markers. Results showed that BHA did not significantly affect the weight of the animal body and spleen in normal mice. BHA promoted macrophage phagocytosis from peripheral blood mononuclear cells, but did not alter this process in the peritoneal cavity. Furthermore, BHA did not influence natural-killer cell cytotoxicity in normal mice. Notably, BHA promoted the levels of CD3 (T cells) and decreased the level of CD19 (B cells), but did not significantly affect the levels of CD11b (monocytes) and macrophages (Mac-3) in normal mice. Based on these observations it can be concluded that BHA promotes immune responses by increasing T cells and activating phagocytosis by macrophages in normal mice. However, the molecular mechanisms require further investigation.
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Arrays of ZnO/Zn(x)Cd(1-x)Se nanocables: band gap engineering and photovoltaic applications.
Nano Lett.
PUBLISHED: 09-02-2011
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Arrays of ZnO/Zn(x)Cd(1-x)Se (0 ? x ? 1) core/shell nanocables with shells of tunable compositions have been synthesized on fluorine-doped tin oxide glass substrates via a simple ion-exchange approach. Through the effects of stoichiometry and type II heterojunction, optical absorptions of the nanocable arrays can be controllably tuned to cover almost the entire visible spectrum. Lattice parameters and band gaps of the ternary Zn(x)Cd(1-x)Se shells were found to have respectively linear and quadratic relationships with the Zn content (x). These ZnO/Zn(x)Cd(1-x)Se nanocable arrays are further demonstrated to be promising photoelectrodes for photoelectrochemical solar cells, giving a maximum power conversion efficiency up to 4.74%.
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Gallic acid induces G?/G? phase arrest and apoptosis in human leukemia HL-60 cells through inhibiting cyclin D and E, and activating mitochondria-dependent pathway.
Anticancer Res.
PUBLISHED: 08-27-2011
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Gallic acid (GA) induces apoptosis in different types of cancer cell lines. In this study, we investigate the apoptotic effects induced by GA in human promyelocytic leukemia HL-60 cells, and clarify the underlying mechanism. Our results showed that GA reduced the viability of HL-60 cells in a dose- and time-dependent manner. GA led to G(0)/G(1) phase arrest in HL-60 cells through promoting p21 and p27 and inhibiting the levels of cyclin D and cyclin E. GA caused DNA damage and fragmentation in HL-60 cells as assayed using DAPI staining and Comet assay. Flow cytometric analysis revealed that GA increased Ca(2+) levels and reduced the mitochondrial membrane potential (??(m)) in HL-60 cells. Apoptotic protein expressions were determined by Western blotting. The results indicated that GA-mediated apoptosis of HL-60 cells mainly depended on mitochondrial pathway, by promoting the release of cytochrome c, apoptosis-inducing factor (AIF) and endonuclease G (Endo G) and by up-regulating the protein expression of Bcl-2-associated X protein (BAX), caspase-4, caspase-9 and caspase-3. In addition, GA also activated the death receptor-dependent pathway by enhancing the protein expressions of fatty acid synthase (FAS), FAS ligand (FASL), caspase-8 and BCL-2 interacting domain (BID). We determined the mRNA expression of the gene levels of these proteins by real-time PCR. The results showed that GA-mediated apoptosis of HL-60 cells mainly depended on up-regulation of the mRNA of caspase-8, caspase-9, caspase-3, AIF and Endo G. In conclusion, GA-induced apoptosis occurs through the death receptor and mitochondria-mediated pathways. The evaluation of GA as a potential therapeutic agent for treatment of leukemia seems warranted.
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A novel synthetic 2-(3-methoxyphenyl)-6,7-methylenedioxoquinolin-4-one arrests the G2/M phase arrest via Cdc25c and induces apoptosis through caspase- and mitochondria-dependent pathways in TSGH8301 human bladder cancer cells.
Int. J. Oncol.
PUBLISHED: 08-20-2011
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2-(3-methoxyphenyl)-6,7-methylenedioxoquinolin-4-one (MMEQ) is a novel synthesized compound, and this study investigated the effects of MMEQ on molecular signal pathways of the induction of apoptosis in TSGH8301 human bladder cancer cells. The studies included examining the effects of morphological changes by contrast-phase microscope, the percentage of viable cells, cell cycle distribution mitochondria membrane potential (??m), ROS and caspase activities were examined by flow cytometry, apoptotic cells were examined by DAPI staining and the changes of associated apoptosis proteins levels were examined by Western blotting. Release of apoptotic factors from mitochondria was examined by confocal laser microscope. Our results showed that MMEQ caused morphological changes and inhibited the cell growth of TSGH8301 cells in a time- and dose-dependent manner. MMEQ induced G2/M arrest through the promotion of chk1, chk2 and cdc25c in TSGH8301 cells. MMEQ caused a marked increase in the percentage of DNA damage and apoptosis as characterized by DAPI and DNA fragmentation. The specific inhibitors of caspase-8, -9, and -3 blocked MMEQ-induced growth inhibition action. A remarkable loss of ??m and increase in ROS production were observed after a 24-h treatment. MMEQ promoted the levels of caspase-3, caspase-8, caspase-9, Bax, Bcl-xs, decreased the levels of Bcl-2 and Bid and then led to dysfunction of ??m, following the releases of cytochrome c, AIF and Endo G from mitochondria to cytosol and nuclei, and finally caused cell apoptosis. In conclusions, these molecular mechanisms provide insight into MMEQ-caused growth inhibition, G2/M arrest and apoptotic cell death in TSGH8301 cells.
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Butein inhibits the migration and invasion of SK-HEP-1 human hepatocarcinoma cells through suppressing the ERK, JNK, p38, and uPA signaling multiple pathways.
J. Agric. Food Chem.
PUBLISHED: 08-03-2011
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Liver cancer is one of the most commonly diagnosed cancers and the leading cause of death in human populations. Butein, a tetrahydroxychalcone, has been shown to induce apoptosis in many human cancer cells, but the effects of butein on the migration and invasion of human liver cancer cells are not reported. Herein, we found that butein is effective in the suppression of migration and invasion in SK-HEP-1 human hepatocarcinoma cells by using the Matrigel cell migration assay and invasion system. The gelatin zymography assay indicated that butein inhibited the activity of matrix metalloproteinases 2 (MMP-2) and MMP-9. Western blotting analysis indicated that butein decreased the levels of MMP-2, -7, and -9, uPA, Ras, Rho A, ROCK1, ERK1/2, JNK1/2, p-p38, and p-c-Jun in SK-HEP-1 cells. Furthermore, butein inhibited the NF-?B binding activity in SK-HEP-1 cells by electrophoretic mobility shift assay. We also found that butein decreased the ERK, JNK, and p38 in SK-HEP-1 cells by in vitro kinase assay. In conclusion, this is the first study to demonstrate that butein might be a novel anticancer agent for the treatment of hepatocarcinoma through inhibiting migration and invasion.
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Large-scale controllable patterning growth of aligned organic nanowires through evaporation-induced self-assembly.
Chemistry
PUBLISHED: 08-02-2011
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Organic one-dimensional nanostructures are attractive building blocks for electronic, optoelectronic, and photonic applications. Achieving aligned organic nanowire arrays that can be patterned on a surface with well-controlled spatial arrangement is highly desirable in the fabrication of high-performance organic devices. We demonstrate a facile one-step method for large-scale controllable patterning growth of ordered single-crystal C(60) nanowires through evaporation-induced self-assembly. The patterning geometry of the nanowire arrays can be tuned by the shape of the covering hats of the confined curve-on-flat geometry. The formation of the pattern arrays is driven by a simple solvent evaporation process, which is controlled by the surface tension of the substrate (glass or Si) and geometry of the evaporation surface. By sandwiching a solvent pool between the substrate and a covering hat, the evaporation surface is confined to along the edge of the solvent pool. The geometry of the formed nanowire pattern is well defined by a surface-tension model of the evaporation channel. This simple method is further established as a general approach that is applicable to two other organic nanostructure systems. The I-V characteristics of such a parallel, organic, nanowire-array device was measured. The results demonstrate that the proposed method for direct growth of nanomaterials on a substrate is a feasible approach to device fabrication, especially to the fabrication of the parallel arrays of devices.
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Etomidate induces cytotoxic effects and gene expression in a murine leukemia macrophage cell line (RAW264.7).
Anticancer Res.
PUBLISHED: 07-09-2011
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Etomidate is an important tool in the arsenal of the emergency physician, and it has been used in a variety of scenarios for both intubation and procedural sedation. In the present study, we investigated the cytotoxicity of etomidate including induction of apoptosis, and levels of protein and gene expressions associated with apoptotic cell death in murine leukemia RAW264.7 cells in vitro. Cytotoxic and apoptotic responses to etomidate of RAW264.7 cells, including cell morphological changes and cell viability were examined and measured by phase-contrast microscopy and flow cytometric assay, respectively. Results indicated that etomidate increased apoptotic cell morphological changes and reduced cell viability in RAW264.7 cells. 4,6-Diamidino-2-phenylindole (DAPI) staining also showed that etomidate induced the formation of apoptotic bodies, a characteristic of apoptosis. Results from Western blotting indicated that etomidate enhanced the levels of cytochrome c, apoptosis-inducing factor (AIF), endonuclease G (Endo G), caspase-9, caspase-3 active form and Bax proteins, but it inhibited the expression of Bcl-xl, leading to apoptosis. DNA microarray assay indicated that etomidate increased the expression of 17 genes (LOC676175; Gm14636; 2810021G02Rik; Iltifb; Olfr1167; Ttc30b; Olfr766; Gas5; Rgs1; LOC280487; V1rd4; Hist1h2bc; V1rj3; Gm10366; Olfr192; Gm10002 and Cspp1) and reduced the expression of 15 genes: (Gm10152; Gm5334; Olfr216; Lcn9; Gm10683; Gm5100; Tdgf1; Cypt2; Gm5595; 1700018F24Rik; Gm10417; Maml2; Olfr591; Trdn and Apol7c). In conclusion, etomidate induced cytotoxic and apoptotic effects the in murine leukemia RAW264.7 cells in vitro.
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Gallic acid inhibits the migration and invasion of A375.S2 human melanoma cells through the inhibition of matrix metalloproteinase-2 and Ras.
Melanoma Res.
PUBLISHED: 07-08-2011
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Melanoma is one of the most common cancers worldwide and its incidence has been increasing over the past few decades. Gallic acid (GA) can inhibit the growth of human cancer cells in vitro and in vivo. However, there is no available information to address the effects of GA on migration and invasion of human skin cancer cells. Matrix metalloproteinases (MMPs), zinc-dependent proteolytic enzymes, play an important role in the invasion, metastasis, and angiogenesis of cancer cells. Therefore, MMPs are one of the targets for agents to suppress and that could inhibit the migration and invasion of cancer cells. GA affected the viable A375.S2 cells by propidium iodide exclusion and flow cytometric analysis. Cell migration and invasion were investigated by Boyden chamber assay and we also determined the levels of protein and mRNA expression cell migration and invasion by gelatin zymography, western blotting, and real-time PCR assays. In this study, we examined the influence of GA on the protein levels and gene expression of MMP-2 and MMP-9 and in-vitro migration and invasiveness of human melanoma cells. GA decreases the MMPs and associated signal pathway protein and MMPs mRNA levels in A375.S2 human melanoma cells. Our findings suggest that GA has antimetastatic potential by decreasing invasiveness of cancer cells. Moreover, this action of GA was involved in the Ras, p-ERK signaling pathways resulting in inhibition of MMP-2 in A375.S2 human melanoma cells. These data, therefore, provide evidence for the role of GA as a potential cancer chemotherapeutic agent, which can markedly inhibit the invasive capacity of melanoma cells.
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Extract of Hedyotis diffusa Willd influences murine leukemia WEHI-3 cells in vivo as well as promoting T- and B-cell proliferation in leukemic mice.
In Vivo
PUBLISHED: 06-29-2011
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Medicinal plants and herbs are widely used in the treatment of various types of cancer in Taiwan, China and many other countries. Hedyotis diffusa Willd (HDW) has been known as a traditional Chinese medicine for a long time, and possesses various bioactivities and anticancer activity. There is no available information on the effects of HDW extracts in leukemic mice and on immune responses in vivo. In this study, we established murine WEHI-3 leukemia in BALB/c mice and hypothesized that an aqueous HDW extract might have antileukemia effects on leukemic animals in vivo. The major characteristic of leukemic mice was an enlarged spleen after intraperitoneal injection with WEHI-3 cells. HDW extract reduced the weights of spleen and liver, but had no significant effect on body weight in WEHI-3 leukemic mice. HDW extract increased the percentage of CD11b cell surface marker (monocytes), but it reduced the percentage of CD3 (T-cell) and CD19 (B-cell) markers. However, HDW extract did not affect the level of Mac-3 and there was no influence on phagocytosis by macrophages from peripheral blood mononuclear cells and the peritoneal cavity in leukemic mice. The isolated splenocytes from HDW extract-treated leukemic mice demonstrated an increase of T- and B-cell proliferation in vivo. Based on these results, HDW extract would appear to have antileukemia activity in WEHI-3 cell-induced leukemia in vivo.
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Gypenosides suppress growth of human oral cancer SAS cells in vitro and in a murine xenograft model: the role of apoptosis mediated by caspase-dependent and caspase-independent pathways.
Integr Cancer Ther
PUBLISHED: 06-10-2011
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Gypenosides (Gyp) are the major components of Gynostemma pentaphyllum Makino. The authors investigated the effects of Gyp on cell morphology, viability, cell cycle distribution, and induction of apoptosis in human oral cancer SAS cells and the determination of murine SAS xenograft model in vivo.
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Synthesis of hollow silica spheres with hierarchical shell structure by the dual action of liquid indium microbeads in vapor-liquid-solid growth.
Langmuir
PUBLISHED: 06-10-2011
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Geometry-based adhesion arising from hierarchical surface structure enables microspheres to adhere to cells strongly, which is essential for inorganic microcapsules that function as drug delivery or diagnostic imaging agents. However, constructing a hierarchical structure on the outer shell of the products via the current microcapsule synthesis method is difficult. This work presents a novel approach to fabricating hollow microspheres with a hierarchical shell structure through the vapor-liquid-solid (VLS) process in which liquid indium droplets act as both templates for the formation of silica capsules and catalysts for the growth of hierarchical shell structure. This hierarchical shell structure offers the hollow microsphere an enhanced geometry-based adhesion. The results provide a facile method for fabricating hollow spheres and enriching their function through tailoring the geometry of their outer shells.
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Phenethyl isothiocyanate (PEITC) promotes G2/M phase arrest via p53 expression and induces apoptosis through caspase- and mitochondria-dependent signaling pathways in human prostate cancer DU 145 cells.
Anticancer Res.
PUBLISHED: 05-28-2011
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Phenethyl isothiocyanate (PEITC), one of many compounds found in cruciferous vegetables, has been reported as a potential anticancer agent. In earlier studies, PEITC was shown to inhibit cell growth and induction of apoptosis in many cancer cell lines. However, no report has shown whether PEITC can induce apoptosis in human prostate cancer cells. Herein, we aimed to determine whether PEITC has anticancer activity in DU 145 human prostate cancer cells. As a result, we found that PEITC induced a dose-dependent decrease in cell viability through induction of cell apoptosis and cell cycle arrest in the G(2)/M phase of DU 145 cells. PEITC induced morphological changes and DNA damage in DU 145 cells. The induction of G(2)/M phase arrest was mediated by the increase of p53 and WEE1 and it reduced the level of CDC25C protein. The induction of apoptosis was mediated by the activation of caspase-8-, caspase-9- and caspase-3-depedent pathways. Results also showed that PEITC caused mitochondrial dysfunction, increasing the release of cytochrome c and Endo G from mitochondria, and led cell apoptosis through a mitochondria-dependent signaling pathway. This study showed that PEITC might exhibit anticancer activity and become a potent agent for human prostate cancer cells in the future.
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Zanthoxylum ailanthoides Sieb and Zucc. extract inhibits growth and induces cell death through G2/M-phase arrest and activation of apoptotic signals in colo 205 human colon adenocarcinoma cells.
Anticancer Res.
PUBLISHED: 05-28-2011
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The effects of 50% ethanolic stem extracts of Zanthoxylum ailanthoides Sieb and Zucc. (ZASZ) on the cell viability, cell cycle and apoptosis were investigated in a human colon adenocarcinoma cell line (colo 205). The results demonstrated that ZASZ induced morphological changes and decreased the cell viability. ZASZ promoted Wee1, checkpoint kinase 2 (CHK2), p21 and p53 levels, decreased cyclin B and cdc25c associated with that led to G(2)/M phase arrest. ZASZ-triggered apoptosis was confirmed by 4 -6-diamidino-2-phenylindole (DAPI) staining and DNA gel electrophoresis. ZASZ increased the levels of glucose-regulated protein 78 (GRP78) and growth arrest and DNA damage inducible gene 153 (GADD153), and promoted an increase of reactive oxygen species (ROS) and Ca(2+) release, and loss of mitochondrial membrane potential (??(m)) accompanied by cytochrome c release that was due to the decrease of Bcl-2 and increase of Bax levels in the colo 205 cells. ZASZ also induced the protein levels of apoptosis-inducing factor (AIF) and endonuclease G (Endo G), increased the levels of caspase-3, -7 and -9, and stimulated the levels of fatty acid synthase (Fas) and Fas ligand in the colo 205 cells. ZASZ contains phenolic compounds, including flavone, chlorogenic acid and isofraxidin, among which, flavone was found to be the most effective in reducing cell viability and proliferative responses in the colo 205 cells. ZASZ induces cytotoxicity and apoptosis in colo 205 cells which provides the rationale for studies in animal models on the utilization of ZASZ as a potential cancer therapeutic compound.
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Danthron inhibits murine WEHI-3 cells in vivo, and enhances macrophage phagocytosis and natural killer cell cytotoxic activity in leukemic mice.
In Vivo
PUBLISHED: 05-18-2011
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Danthron has been shown to induce apoptotic cell death, and inhibit migration and invasion of human gastric or brain cancer cells in vitro. However, there is no report addressing whether danthron affects murine leukemia cells or immune responses in vivo. Herein, this study focused on the in-vivo effects of danthron on WEHI-3 leukemia in mice and immune responses in vivo. The results indicated that danthron reduced spleen weight and increased the percentage of cells with CD3 and CD19 markers, indicating that differentiation of the precursors of T- and B-cells was promoted in the leukemic mice. The results also showed that danthron promoted the activity of phagocytosis by macrophages isolated from the peritoneal cavity but had no effect on peripheral blood mononuclear cells. Danthron also promoted natural killer cell cytocytic activity at an effector and target cell ratio of 100:1 in comparison with leukemic animals in vivo. Taken together, these results demonstrated that application of danthron might affect WEHI-3 leukemia in mice and modulate immune responses in vivo.
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