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Find video protocols related to scientific articles indexed in Pubmed.
The Effect of Iatrogenic Staphylococcus epidermidis Intercellar Adhesion Operon on the Formation of Bacterial Biofilm on Polyvinyl Chloride Surfaces.
Surg Infect (Larchmt)
PUBLISHED: 11-18-2014
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Abstract Background: The intercellular adhesion gene (ica) of Staphylococcus epidermidis is a key factor for bacterial aggregation. This study explored the effect of ica on the formation of bacterial biofilm on polyvinyl chloride (PVC) surfaces. Methods: Genes related to bacterial biofilm formation, including 16S rRNA, autolysin (atlE), fibrinogen binding protein gene (fbe), and ica were identified and sequenced from 112 clinical isolates of iatrogenic S. epidermidis by polymerase chain reaction (PCR) and gene sequencing. Based on the sequencing result, ica operon-positive (icaADB+/atlE+/fbe+) and ica operon-negative (icaADB-/atlE+/fbe+) strains were separated and co-cultivated with PVC material. After 6, 12, 18, 24, and 30?h of co-culture, the thickness of the bacterial biofilm and quantity of bacterial colony on the PVC surface were measured under the confocal laser scanning microscope and scanning electron microscope. Results: The positive rate of S. epidermidis-specific 16SrRNA in 112 iatrogenic strains was 100% (112/112). The genotype of ica-positive (icaADB+/atlE+/fbe+) strains accounted for 57.1% (64/112), and genotype of ica-negative (icaADB-/atlE+/fbe+) strains accounted for 37.5% (42/112). During 30?h of co-culture, no obvious bacterial biofilm formed on the surface of PVC in the ica-positive group, however, mature bacterial biofilm structure formed after 24?h. For all time points, thickness of bacterial biofilm and quantity of bacterial colony on PVC surfaces in the ica operon-positive group were significantly higher than those in ica operon-negative group (p<0.01). Conclusions: Iatrogenic S. epidermidis can be categorized into ica operon-negative and ica operon-positive strains. The ica operon plays an important role in bacterial biofilm formation and bacterial multiplication on PVC material.
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Physical Deposition Improved SERS Stability of Morphology Controlled Periodic Micro/Nanostructured Arrays Based on Colloidal Templates.
Small
PUBLISHED: 09-01-2014
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An effective and inexpensive method is developed to fabricate periodic arrays by sacrificial colloidal monolayer template route by chemical deposition and further physical deposition. By a colloidal template induced precursor solution dipping strategy, different periodic arrays of semi-hollow sphere array, inverse opal with monolayer pore arrays and hole arrays are obtained under different conditions. After magnetron sputtering deposition, their morphologies are changed to novel micro/nanostructured arrays of honeycomb-shaped arrays, hollow cavity arrays, and regular network arrays due to multiple direction deposition of sputtering deposition and shadow effect. After coating a gold thin layer, these periodic micro/nanostructured arrays are used as SERS active substrates and demonstrate a very stable SERS performance compared with periodic arrays achieved by direct colloidal template-induced chemical deposition. Additionally, a honeycomb-shaped array displays better SERS enhancement than that of a hollow cavity array or a regular network array. After optimization of honeycomb-shaped arrays with different periodicities, an array with periodicity of 350 nm demonstrates much stronger SERS enhancement and possesses a low detection limit of 10(-11) M R6G. Such stable SERS performance is useful for practical application in portable Raman detecting devices to detect organic molecules.
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[Postoperative complications of bilobectomy compared with lobectomy in the right lung of non-small cell lung cancer patients].
Zhongguo Fei Ai Za Zhi
PUBLISHED: 08-19-2014
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The mismatch between pleural space and remnant lung after bilobectomy has been considered as the main reason for the high incidence of postoperative complications in non-small cell lung cancer (NSCLC) patients. The aim of this study is to analyze the differences in postoperative complications between bilobectomy and lobectomy in the right lung of NSCLC patients.
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Analysis of the transcriptome of Marsdenia tenacissima discovers putative polyoxypregnane glycoside biosynthetic genes and genetic markers.
Genomics
PUBLISHED: 08-13-2014
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Marsdenia tenacissima is a well-known anti-cancer medicinal plant used in traditional Chinese medicine due to bioactive constituents of polyoxypregnane glycosides, such as tenacissosides, marsdenosides and tenacigenosides. Genomic information regarding this plant is very limited, and rare information is available about the biosynthesis of polyoxypregnane glycosides. To facilitate the basic understanding about the polyoxypregnane glycoside biosynthetic pathways, de novo assembling was performed to generate a total of 73,336 contigs and 65,796 unigenes, which represent the first transcriptome of this species. These included 27 unigenes that were involved in steroid biosynthesis and could be related to pregnane backbone biosynthesis. The expression patterns of six unigenes involved in polyoxypregnane biosynthesis were analyzed in leaf and stem tissues by quantitative real time PCR (qRT-PCR) to explore their putative function. Furthermore, a total of 15,295 simple sequence repeats (SSRs) were identified from 11,911 unigenes, of which di-nucleotide motifs were the most abundant.
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Pro-apoptotic effects of the novel tangeretin derivate 5-acetyl-6,7,8,4'-tetramethylnortangeretin on MCF-7 breast cancer cells.
Cell Biochem. Biophys.
PUBLISHED: 06-19-2014
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Citrus polymethoxyflavone tangeretin (5,6,7,8,4'-pentamethoxyflavone, TAN) displays multiple biological activities, but previous reports showed that TAN failed to induce MCF-7 human breast cancer cells apoptosis. Herein, we prepared 5-acetyl-6,7,8,4'-tetramethylnortangeretin (5-ATAN), and evaluated its cytotoxicity on MCF-7 cells. 5-ATAN revealed stronger cytotoxicity than that of parent TAN in the growth inhibition of MCF-7 cells. 5-ATAN induced apoptosis via both caspase-independent and -dependent pathways, in which 5-ATAN induced the translocation of apoptosis inducing factor and phosphorylation of H2AX as well as poly (ADP-ribose) polymerase cleavage, caspase-3 activation. However, 5-ATAN did not affect extrinsic markers caspase-8, BID, and FADD. Further, 5-ATAN induced the loss of mitochondrial membrane potential (??m) by regulating the Bax/Bcl-2 ratio. Loss of ??m led to the mitochondrial release of cytochrome c which triggered activation of caspase-9. In conclusion, these data indicate that 5-ATAN plays pro-apoptotic cytotoxic roles in MCF-7 cells through both caspase-dependent intrinsic apoptosis and caspase-independent apoptosis pathways.
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Wet etching-assisted colloidal lithography: a general strategy toward nanodisk and nanohole arrays on arbitrary substrates.
ACS Appl Mater Interfaces
PUBLISHED: 06-03-2014
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A simple and facile strategy is presented to fabricate the metal nanodisk and nanohole arrays based on a wet etching-assisted polystyrene colloidal lithography. Gold is chosen to demonstrate the validity of such a strategy. The hexagonally arranged Au nanodisk and nanohole arrays are thus fabricated with large area and good uniformity. The structural parameters of the arrays, such as thicknesses, diameters, and spacings of the nanodisks or nanoholes, are facilely tunable and controllable by predeposition conditions, etching conditions and colloidal monolayer structure. More importantly, these arrays can be produced on any supporting substrates, such as conductive or nonconductive and even flexible substrates with flat, rough, or even curved surfaces. In general, the presented strategy is low in cost, simple in operation and arbitrary in substrate, and the as-prepared arrays could find potential devices' applications with nice compatibility in the fields of optics, surface-enhanced Raman spectroscopy, biosensing, and so forth.
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[Accumulation-associated protein gene and TGF-beta 1 affects the formation of lung cancer-related biological material Staphylococcus epidermidis biofilm].
Zhongguo Fei Ai Za Zhi
PUBLISHED: 04-25-2014
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This study was conducted to evaluate the effects of the accumulation-associated protein (Aap) gene and transform growth factor-beta 1 (TGF-?1) on the biofilm formation of lung cancer-related Staphylococcus epidermidis (SE).
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Nonlinear quantitative radiation sensitivity prediction model based on NCI-60 cancer cell lines.
ScientificWorldJournal
PUBLISHED: 04-07-2014
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We proposed a nonlinear model to perform a novel quantitative radiation sensitivity prediction. We used the NCI-60 panel, which consists of nine different cancer types, as the platform to train our model. Important radiation therapy (RT) related genes were selected by significance analysis of microarrays (SAM). Orthogonal latent variables (LVs) were then extracted by the partial least squares (PLS) method as the new compressive input variables. Finally, support vector machine (SVM) regression model was trained with these LVs to predict the SF2 (the surviving fraction of cells after a radiation dose of 2?Gy ?-ray) values of the cell lines. Comparison with the published results showed significant improvement of the new method in various ways: (a) reducing the root mean square error (RMSE) of the radiation sensitivity prediction model from 0.20 to 0.011; and (b) improving prediction accuracy from 62% to 91%. To test the predictive performance of the gene signature, three different types of cancer patient datasets were used. Survival analysis across these different types of cancer patients strongly confirmed the clinical potential utility of the signature genes as a general prognosis platform. The gene regulatory network analysis identified six hub genes that are involved in canonical cancer pathways.
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MnO2 nanorods intercalating graphene oxide/polyaniline ternary composites for robust high-performance supercapacitors.
Sci Rep
PUBLISHED: 03-17-2014
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New ternary composites of MnO2 nanorods, polyaniline (PANI) and graphene oxide (GO) have been prepared by a two-step process. The 100?nm-long MnO2 nanorods with a diameter ~20?nm are conformably coated with PANI layers and fastened between GO layers. The MnO2 nanorods incorporated ternary composites electrode exhibits significantly increased specific capacitance than PANI/GO binary composite in supercapacitors. The ternary composite with 70% MnO2 exhibits a highest specific capacitance reaching 512?F/g and outstanding cycling performance, with ~97% capacitance retained over 5000 cycles. The ternary composite approach offers an effective solution to enhance the device performance of metal-oxide based supercapacitors for long cycling applications.
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Inhibitory effect of Disulfiram/copper complex on non-small cell lung cancer cells.
Biochem. Biophys. Res. Commun.
PUBLISHED: 03-09-2014
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Non-small cell lung cancer (NSCLC) is the most common cause of cancer-related death in both men and women worldwide. Recently, Disulfiram has been reported to be able to inhibit glioblastoma, prostate, or breast cancer cell proliferation. In this study, the synergistic effect of Disulfiram and copper on NSCLC cell growth was investigated. Inhibition of cancer cell proliferation was detected by 1-(4,5-Dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT) assay and cell cycle analysis. Liquid colony formation and tumor spheroid formation assays were used to evaluate their effect on cancer cell clonogenicity. Real-time PCR was performed to test the mRNA level of cancer stem cell related genes. We found that Disulfiram or copper alone did not potently inhibit NSCLC cell proliferation in vitro. However, the presence of copper significantly enhanced inhibitory effect of Disulfiram on NSCLC cell growth, indicating a synergistic effect between Disulfiram and copper. Cell cycle analysis showed that Disulfiram/copper complex caused NSCLC cell cycle arrest in G2/M phase. Furthermore, Disulfiram/copper significantly increased the sensitivity of cisplatin in NSCLC cells tested by MTT assay. Liquid colony formation assay revealed that copper dramatically increased the inhibitory effect of Disulfiram on NSCLC cell colony forming ability. Disulfiram combined with copper significantly attenuated NSCLC cell spheroid formation and recuded the mRNA expression of lung cancer stem cell related genes. Our data suggest that Disulfiram/copper complex alone or combined with other chemotherapy is a potential therapeutic strategy for NSCLC patients.
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CuO-ZnO micro/nanoporous array-film-based chemosensors: new sensing properties to H2S.
Chemistry
PUBLISHED: 02-09-2014
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CuO-ZnO micro/nanoporous array-films are synthesized by transferring a solution-dipped self-organized colloidal template onto a device substrate and sequent heat treatment. Their morphologies and structures are characterized by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectrum analysis. Based on the sensing measurement, it is found that the CuO-ZnO films prepared with the composition of [Cu(2+)]/[Zn(2+)]=0.005, 0.01, and 0.05 all show a nice sensitivity to 10?ppm H2S. Interestingly, three different zones exist in the patterns of gas responses versus H2S concentrations: a platform zone, a rapidly increasing zone, and a slowly increasing zone. Further experiments show that the hybrid CuO-ZnO porous film sensor exhibits shorter recovery time and better selectivity to H2S gas against other interfering gases at a concentration of 10?ppm. These new sensing properties may be due to a depletion layer induced by p-n junction between p-type CuO and n-type ZnO and high chemical activity of CuO to H2S. This work will provide a new construction route of ZnO-based sensing materials, which can be used as H2S sensors with high performances.
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Gold binary-structured arrays based on monolayer colloidal crystals and their optical properties.
Small
PUBLISHED: 01-26-2014
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A simple and flexible route is presented to fabricate a gold binary-structured ordered array by one step based on non-shadow deposition on a plasma etching-induced dualistic monolayer colloidal crystal. Such a Au binary-structure array is built of hexagonally arranged nanoshells and nanorings which stand between two adjacent nanoshells. Six gold nanorings surround each nanoshell. The obtained arrays exhibit both the controllable surface-plasmon-resonance (SPR) properties of Au nanoshells and the strong electromagnetic-field-enhancement effects of Au nanorings, with the high structural stability of ordered arrays, and show promising potential as the substrate of surface-enhanced Raman scattering (SERS)-based devices. The method could also be suitable for fabrication of other material binary-structured arrays. This study is important in designing and fabricating basal materials for the next generation of multifunctional nanostructured devices.
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MicroRNA-195 inhibits non-small cell lung cancer cell proliferation, migration and invasion by targeting MYB.
Cancer Lett.
PUBLISHED: 01-20-2014
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MicroRNA-195 (miR-195) has been implicated in several other cancers; however, its role in non-small cell lung cancer (NSCLC) remains unclear. In this study, we demonstrated that miR-195 was significantly down-regulated in NSCLC samples and cell lines compared with corresponding normal counterparts. In vitro and in vivo functional assays demonstrated that modulation of miR-195 expression affected NSCLC cell proliferation, migration and invasion. Using miRNA target prediction algorithms and reporter assays, we demonstrated that miR-195 suppressed the expression of MYB both at the mRNA and protein level, and was directly bound to the 3'untranslated region of MYB mRNA. Overexpression of MYB in NSCLC cells using an ectopic expression vector restored the decreased cell proliferation, migration and invasion effects induced by miR-195. Finally, we observed an inverse correlation between MYB and miR-195 in NSCLC. Taken together, our findings indicated that miR-195 functions as tumour suppressor in NSCLC, and the miR-195/MYB axis might represent a potential therapeutic target for NSCLC intervention.
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Stability of miR-126 in Urine and Its Potential as a Biomarker for Renal Endothelial Injury with Diabetic Nephropathy.
Int J Endocrinol
PUBLISHED: 01-10-2014
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Background. The purpose of the present study was to assess the feasibility of using miR-126 in the urine as a biomarker for diabetic nephropathy. Methods. miRNAs were extracted from the urine samples of T2DM patients with diabetic nephropathy (DN; n = 92), T2DM without DN (n = 86), and 85 healthy volunteers using quantitative reverse transcriptase polymerase chain reaction (real-time polymerase chain reaction) analysis. Stability of urinary miR-126 and factors that affected the stability were assessed. A subgroup analysis was also carried out to compare the urinary miR-126 level in T2DM patients well controlled by the treatment versus those who were not well controlled. Results. Urinary miR-126 was stable when the urine samples were kept at room temperature for extended period of time, 4°C, -20°C, and -80°C for up to 12 hours or subjected to 10 freeze-and-thaw cycle. Urinary miR-126 was significantly higher in T2DM patients with DN (5.76 ± 0.33 versus 3.25 ± 0.45 in T2DM patients without DN). Successful treatment significantly reduced urinary miR-126 in T2DM patients with DN to 3.89 ± 0.52 (P < 0.05). Conclusion. miR-126 in the urine is stable and it could be used as a biomarker of DN and to monitor the treatment response.
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The role of circulating microRNA-126 (miR-126): a novel biomarker for screening prediabetes and newly diagnosed type 2 diabetes mellitus.
Int J Mol Sci
PUBLISHED: 01-02-2014
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Recent studies suggested an association of endothelial microRNA-126 (miR-126) with type 2 diabetes mellitus (T2DM). In the current study, we examined whether circulating miR-126 is associated with T2DM and pre-diabetic syndrome. The study included 82 subjects with impaired glucose tolerance (IGT), 75 subjects with impaired fasting glucose (IFG), 160 patients with newly diagnosed T2DM, and 138 healthy individuals. Quantitative polymerase chain reaction (qPCR) was used to examine serum miR-126. Serum miR-126 was significantly lower in IGT/IFG subjects and T2DM patients than in healthy controls (p<0.05). After six months of treatment (diet control and exercise in IGT/IFG subjects, insulin plus diet control and exercise in T2DM patients), serum miR-126 increased significantly (p<0.05). An analysis based on serum miR-126 in the sample revealed a significantly higher odds ratio (OR) for the subjects with the lowest 1/3 of serum miR-126 for T2DM (OR: 3.500, 95% confidence interval: 1.901-6.445, p<0.05) than subjects within the highest 1/3 of serum miR-126. Such an association was still apparent after adjusting for other major risk factors. The area under the curve (AUC) for the receiver-operating characteristic (ROC) analysis was 0.792 (95% confidence interval: 0.707-0.877, p<0.001). These results encourage the use of serum miR-126 as a biomarker for pre-diabetes and diabetes mellitus, as well as therapeutic response.
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Fabrication of Gold Nanoparticles by Laser Ablation in Liquid and Their Application for Simultaneous Electrochemical Detection of Cd(2+), Pb(2+), Cu(2+), Hg(2+)
ACS Appl Mater Interfaces
PUBLISHED: 12-16-2013
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In this paper, we demonstrated the fabrication of high active and high sensitive Au nanoparticles by laser ablation in liquid (LAL) method, and their application in electrochemical detection of heavy metal ions. First, LAL method are used to fabricate Au nanoparticles in water in a clean way. Second, the Au nanoparticles were assembled onto the surface of the glassy carbon (GC) electrode by an electrophoretic deposition method to form an AuNPs/GC electrode for electrochemical characterization and detection. Through differential pulse anodic stripping voltammetry method, it shows that the AuNPs/GC electrode could be used for the simultaneous and selective electrochemical detection of Cd(2+), Pb(2+), Cu(2+), and Hg(2+). By studying the influence of test conditions to optimize the electrochemical detection, we can detect Cd(2+), Pb(2+), Cu(2+), and Hg(2+) simultaneously with a low concentration of 3 × 10(-7) M in the experiments.
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Fabrication of porous Ag hollow sphere arrays based on coated template-plasma bombardment.
Nanotechnology
PUBLISHED: 10-22-2013
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A facile and flexible strategy is presented to produce porous Ag hollow sphere arrays, with a micro/nanostructure and contaminant-free surface, based on a combination of the bottom-up and top-down fabrication strategies, or by plasma bombardment of Ag-coated monolayer polystyrene sphere templates. The arrays consist of periodically arranged micro-sized hollow spheres with nanoscaled pores (mostly within 100 nm) in the shell layer. These arrays are structurally tunable in spherical size (in the sub-10 ?m range), spacing (from a few nanometers to several microns), shell thickness (over tens of nanometers) and porous configuration by the template and bombarding conditions. The strategy is universal for the fabrication of other porous metal hollow sphere arrays. Such nanoscaled rough and porous Ag hollow sphere arrays have potential applications in catalysis, antibacterial and photonic devices. The arrays show significant surface-enhanced Raman scattering (SERS) activity (the minimum detectable concentration of the standard molecule rhodamine 6G can be down to 10(-14) M) with good stability and reproduction, and are a good candidate for the substrate of SERS effect based devices.
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The multiparty coherent channel and its implementation with linear optics.
Opt Express
PUBLISHED: 10-10-2013
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The continuous-variable coherent (conat) channel is a useful resource for coherent communication, supporting coherent teleportation and coherent superdense coding. We extend the conat channel to multiparty conditions by proposing definitions on multiparty position-quadrature and momentum-quadrature conat channel. We additionally provide two methods to implement this channel using linear optics. One method is the multiparty version of coherent communication assisted by entanglement and classical communication (CCAECC). The other is multiparty coherent superdense coding.
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The Effect of Brominated Furanones on The Formation of Staphylococcus aureus Biofilm on PVC.
Cell Biochem. Biophys.
PUBLISHED: 08-28-2013
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To study the influence of brominated furanones on the formation of Staphylococcus aureus (SA) biofilm on PVC thus providing new avenues of research on the surface modification of materials and clinical treatment of biomaterial-centered infection. Three brominated furanones (furanone-1, furanone-2, and furanone-3) were coated on the surface of PVC material. Both the modified PVC materials and SA were co-cultivated together. To assess the thickness of bacterial biofilm and bacterium colony unit area on PVC materials, confocal laser scanning microscopy and scanning electron microscopy (SEM) were used to observe the surface structure of SA biofilm formation. All treatments were compared with the control group which was not coated with furanones. PVC materials coated with furanone-1 had an increase in bacterial biofilm as well as SA colony area when compared with control. However, there was no significant difference between treating with furanone-1 and furanone-3 (P > 0.05). The impact of different brominated furanones on SA biofilm formation on the surface of PVC materials is different, furanone-1 can promote the SA biofilm formation on the surface of PVC material.
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Synthesis and biological evaluation of 2,6-dichloropurine bicyclonucleosides containing a triazolyl-carbohydrate moiety.
Carbohydr. Res.
PUBLISHED: 08-14-2013
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A series of bicyclic nucleosides containing a triazolyl-carbohydrate moiety were synthesized and their antitumor activity in vitro for human cancer cell lines was also tested. Compound 11 was synthesized efficiently with 3,6-anhydro sugar 7 as raw material, while compound 7 was prepared from 1,2;5,6-di-O-isopropylidene-?-d-glucose. Compounds 12a-e were synthesized by treating compound 11 with alkynes, catalyzed by copper(I). After removal of the acetyl protecting groups, the target compounds 5a-e showed significant inhibitory activity against EC109, PC-3, MGC-803, and HGC-7 cell lines.
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The Roles of Moonlighting Proteins in Bacteria.
Curr Issues Mol Biol
PUBLISHED: 07-23-2013
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Moonlighting proteins, characterized by their multiple autonomous functions, have been detected in bacteria. Surprisingly, many of these proteins are conserved and involved in metabolic pathway or the cell stress response. They localise to the bacterial surface to take on additional activities, which have been hypothesised to contribute to bacterial virulence or bacterial benefit. In this review, we compare the functions of moonlighting proteins in bacteria, describe the structural basis of moonlighting functions, and summarise the regulation of secretion and localisation of moonlighting proteins.
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UV light assisted synthesis of ternary reduced graphene oxide hybrid materials and their photocatalytic performance.
Dalton Trans
PUBLISHED: 07-12-2013
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Freely-assembled ternary hybrids consisting of Pt, reduced graphene oxide (RGO) and P25 were synthesized by a direct solution process with the assistance of UV light. The Pt-RGO/P25 hybrids were characterized by Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet visible (UV-vis) diffuse reflectance spectroscopy (DRS) and photoluminescence spectra (PL). Importantly, when Pt-RGO/P25 hybrids were used as photocatalysts, they could show a superior photocatalytic performance when compared to commercial P25 and RGO/P25 hybrids under UV, solar light and ? > 600 nm visible light irradiation, which could be explained on the basis of the plasmonic response and the formation of Pt Schottky barrier at the interface between TiO2 and graphene. This work could provide new insight for enhancing graphene/TiO2 photocatalytic performance and facilitate their application in environmental protection.
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Limited relationships between two-year changes in sulcal morphology and other common neuroimaging indices in the elderly.
Neuroimage
PUBLISHED: 05-16-2013
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Measuring the geometry or morphology of sulcal folds has recently become an important approach to investigating neuroanatomy. However, relationships between cortical sulci and other brain structures are poorly understood. The present study investigates how age-related changes in sulcal width are associated with age-related changes in traditional indices of brain structure such as cortical thickness, and cortical gray matter (GM), white matter (WM), subcortical, and white matter hyperintensity (WMH) volumes. These indices and sulcal width were measured at baseline and at two-year follow up in 185 community-dwelling individuals (91 men) aged 70-89 years. There were significant increases in sulcal width and WMH volume, and significant decreases in all other indices between baseline and follow-up. Sulcal widening was associated with decreases in cortical GM, subcortical and WM volumes. A further association between sulcal width and cortical thickness became non-significant when cortical GM volume was controlled for. Our findings give insights into the mechanisms responsible for cortical sulcal morphology. The relationships between sulcal morphology and other common measures suggest that it could be a more comprehensive measure for clinical classifications than traditional neuroimaging metrics, such as cortical thickness.
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Establishment of a novel one-step reverse transcription loop-mediated isothermal amplification assay for rapid identification of RNA from the severe fever with thrombocytopenia syndrome virus.
J. Virol. Methods
PUBLISHED: 04-18-2013
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As an emerging infectious disease, severe fever with thrombocytopenia syndrome virus (SFTSV) infection has been found in many areas of China. Suitable laboratory diagnostic method is urgently needed in clinical detections and epidemiological investigations. In this study, a modified, low-cost and rapid visualized one-step reverse transcription loop-mediated isothermal amplification (RT-LAMP) method for the detection of RNA from the SFTSV has been established. In order to avoid the risk of aerosol contamination and facilitate the naked eye to observe, a microcrystalline wax-dye capsule wrapping the highly sensitive DNA fluorescence dye SYBR Green I was added to the RT-LAMP reaction tube before the initiation of the assay. The detection limit of the established RT-LAMP assay was 10 fg template RNA per reaction mixture. The RT-LAMP assay was confirmed to be high specific to SFTSV, and no cross-reaction was found with the detection of the Chikungunya fever virus, Hemorrhagic Fever with Renal Syndrome virus (HFRSV), and Dengue fever virus. The assay was then applied for the detection of SFTSV RNA in 32 clinical serum samples and showed 94.4% consistence with the detection results of the real-time RT-PCR. The whole process, from sample preparation to result reporting, can be completed within 2h. This adapted, cost efficient and quick visualized RT-LAMP method is feasible for SFTSV field diagnosis in resource-limited field settings.
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Effect of Brominated Furanones on the Formation of Biofilm by Escherichia coli on Polyvinyl Chloride Materials.
Cell Biochem. Biophys.
PUBLISHED: 04-04-2013
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To study the influence of brominated furanones on the biofilm (BF) formation by Escherichia coli (E. coli) on polyvinyl chloride (PVC) material, and to provide new ways of surface modification of materials to clinically prevent biomaterial centered infection. Three brominated furanones, dissolved in ethanol, furanone-1(3,4-dibromo-5-hydroxyl-furanone), furanone-2(4-bromo-5-(4-methoxypheny)-3-(methylamino)-furanone), and furanone-3(3,4-dibromo-5,5-dimethoxypheny-2(5H)-furanone) with representative chemical structure, were coated on the surfaces of separate PVC materials (1 × 1 cm), respectively. The surface-modified PVC materials were incubated with E. coli and for controls, 75 % ethanol-treated PVC materials were used. This treatment played as control group. The cultivation incubations were for 6, 12, 18, and 24 h. The thickness of bacterial BF and bacterial community quantity unit area on the PVC materials was determined by confocal laser scanning microscopy (CLSM), and the surface structure of bacterial BF formation was examined by scanning electron microscopy (SEM). The results of CLSM indicated the thickness of bacterial BF and bacterial community quantity unit area on PVC materials treated with furanone-3 were significantly lower than that of control at all time points (P < 0.05), whereas, the differences between furanone-1 and furanone-2 groups and control group were not significantly different (P > 0.05). The results of SEM indicated that after 6 h incubation, the quantity of bacterial attachment to the surface of PVC material treated with furanone-3 was lower than the control group. By 18 h incubation there was completely formed BF structure on the surface of control PVC material. However, there was no significant BF formation on the surface of PVC material treated with furanone-3. The impact of different brominated furanones on SA biofilm formation on the surface of PVC materials are different, furanone-3 can inhibit E. coli biofilm formation on the surface of PVC material.
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Absence of the superior mesenteric artery in an adult and a new classification method for superior-inferior mesenteric arterial variations.
Surg Radiol Anat
PUBLISHED: 03-27-2013
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This paper aims to report the complete absence of the superior mesenteric artery (SMA) in an adult and to propose a new classification method for the superior-inferior mesenteric arterial variations (SIMAV).
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[Subcellular distribution and genotoxicity of silica nanoparticles in human bronchial epithelial cells].
Zhongguo Fei Ai Za Zhi
PUBLISHED: 03-22-2013
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Silicon nanoparticles are widely used in daily life. Therefore, they attract increased attention because of their potential biotoxicity to the lungs when inhaled. The aims of this study are to explore the organism distribution and genotoxicity of silica nanoparticles in human bronchial epithelial cells (BEAS-2B).
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Resistin protection against endogenous A? neuronal cytotoxicity from mitochondrial pathway.
Brain Res.
PUBLISHED: 03-14-2013
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Neurotoxicity of amyloid ? (A?) plays an important role in Alzheimers disease (AD) pathogenesis. In this study, we researched the potential protective effects of resistin against A? neurotoxicity in mouse Neuro2a (N2a) cells transfected with the Swedish amyloid precursor protein (Sw-APP) mutant and Presenilin exon 9 deletion mutant (N2a/D9), which overproduced A? with abnormal intracellular A? accumulation. The results show increased levels of ROS, NO, protein carbonyls, and 4HNE in N2a/D9 cells, which were attenuated by resistin treatment in a dose dependent manner. We also found that resistin could improve mitochondrial function in N2a/D9 cells through increasing the level of ATP and mitochondrial membrane potential. MTT and LDH assay indicated that N2a/D9 cells show increased vulnerability to H2O2-induced insult, which could be ameliorated by resistin. Mechanically, we found that resistin prevented apoptosis signals through reducing the ratio of Bax/Bcl2, the level of cleaved caspase-3, and attenuating cytochrome C release. Finally, the results demonstrated that resistin did not change the production of A?1-40 and A?1-42 in N2a/D9 cells, which suggests that the protective effects of resistin are independent of APP metabolism. This raises the possibility of novel AD therapies using resistin.
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An invisible template method toward gold regular arrays of nanoflowers by electrodeposition.
Langmuir
PUBLISHED: 03-06-2013
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A new approach, an invisible template method that is realized through controlling the interface electroconductivity of an electrode surface, is presented to synthesize gold regular arrays of nanoflowers with variable separations through further electrochemical deposition. Using polystyrene monolayer colloidal crystals as the first template, a hexagonally packed 1-hexadecanethiol pattern was self-assembled and used as an invisible template to control the interface electroconductivity. Further electrochemical deposition under appropriate conditions can easily lead to gold regular arrays of nanoflowers. This new approach demonstrates a simple route to the fabrication of novel gold micro/nanostructured arrays that may find applications as SERS active substrates, superhydrophobic materials, and so forth.
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How are the non-classically secreted bacterial proteins released into the extracellular milieu?
Curr. Microbiol.
PUBLISHED: 02-25-2013
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Most bacterial proteins that are destined to leave the cytoplasm are exported across the cell membrane to their sites of function. These proteins are generally exported via the classical secretion pathway, in which the signal peptide plays a central role. However, some bacterial proteins have been found in the extracellular milieu without any apparent signal peptide. As none of the classical secretion systems is involved in their secretion, this occurrence is termed non-classical protein secretion. The mechanism or mechanisms responsible for non-classical secretion are contentious. This review compiles evidence from the debate over whether the release of the non-classically secreted proteins is the result of cell lysis and discusses how these proteins are exported to the exterior of the cell.
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Layer-controlled synthesis of WO? ordered nanoporous films for optimum electrochromic application.
Nanoscale
PUBLISHED: 02-15-2013
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We report on a layer-controlled fabrication of two-dimensional (2D) WO3 ordered nanoporous films via a step-by-step template-assisted strategy. For this purpose, a polystyrene sphere monolayer colloidal crystal (MCC), capable of intact transfer, is adopted as the fabrication template. WO3 nanoporous films with a monolayer (L1), bilayer (L2) and trilayer (L3) were typically constructed and technical analysis illustrates that each layer is composed of fully crystalline monoclinic WO3 nanoparticles and aggregated skeletons possessing hexagonally ordered arrangements at long range. Electrochromic characterization reveals that the ITO-based WO3 nanoporous films have long cycling stability over time and improved cation insertion/extraction capacities with increasing film layer. The inserted/extracted cations of the L2 film are nearly twice that of L1, while slightly inferior to that of L3. For the L3 film, the excessive layer thickness results in longer cation diffusion path lengths, leading to relatively poor charge reversibility. Therefore, the WO3 nanoporous bilayer films prepared in our work show optimum electrochromic properties after comprehensive characterization. Additionally, the uniform nanoporous film prepared by the proposed strategy can be successfully constructed onto a curved ceramic substrate with rough surfaces, which is still a challenge for traditional spin- or dip-coating methods. This substrate-compatible feature will facilitate construction of specific functional devices and layer-controlled fabrication by a low-cost strategy could find promising applications in chemical sensors, electrochromic windows, and so on.
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Physical processes-aided periodic micro/nanostructured arrays by colloidal template technique: fabrication and applications.
Chem Soc Rev
PUBLISHED: 02-12-2013
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It has been proven that the use of colloidal templates is a facile, flexible strategy to create the periodic micro/nanostructured arrays in comparison with photolithography, electron beam lithography etc. Utilizing colloidal monolayers as templates or masks, different periodic micro/nanostructured arrays including nanoparticle arrays, pore arrays, nanoring arrays and nanorod/nanotube arrays can be fabricated by chemical and physical processes. Chemical routes, including direct solution/sol dipping strategy, wet chemical etching, electrodeposition, electrophoretic deposition etc. have advantages of simple operation and low costs. However, they have some disadvantages of impurities on surface of arrays due to incomplete decomposition of precursors, residue of surfactants in self-assembling or electrochemical deposition. More importantly, it is quite difficult to achieve very uniform morphology of micro/nanostructure arrays on a large-area by the above routes. Whereas another method, a physical route (for instance: reactive ion etching, pulsed laser deposition, thermal evaporation deposition, atomic layer deposition, sputtering deposition), combining with colloidal monolayer template can well resolve these problems. In this review, we focus on introducing the recent progress in creating micro/nanostructured arrays based on colloidal templates with physical routes. The parameters of the microstructure or nanostructure can be tuned by colloidal templates with different periodicity and experimental conditions of the physical processes. The applications of micro/nanostructured arrays with controllable morphology and arrangement parameters in self-cleaning surfaces, enhanced catalytic properties, field emitters etc. are also presented in the following sections.
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The secretion of an intrinsically disordered protein with different secretion signals in Bacillus subtilis.
Curr. Microbiol.
PUBLISHED: 01-12-2013
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In this study, a naturally unsecretory intrinsically disordered domain of nucleoskeletal-like protein (Nsp) was attempted to be secreted with different types of secretion signals in Bacillus subtilis. The results showed that Nsp can be secreted efficiently by all selected Sec-type signal peptides. Nsp was successfully exported when fused to Tat-type signal peptides but less efficient than Sec-type. The fusion protein with the non-classical extracellular proteins can be detected in the cell and extracellular milieu. This study further demonstrated that the mature protein plays an important role in protein secretion. Moreover, these results indicated that Nsp could be a useful tool to understand the individual roles of mature proteins and signal peptide in protein secretion, to evaluate the effect of conformation of mature proteins on their export pathway when coupled with Tat-type signal peptide, and to seek the signal of non-classical secretory proteins.
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Trace detection of cyanide based on SERS effect of Ag nanoplate-built hollow microsphere arrays.
J. Hazard. Mater.
PUBLISHED: 01-10-2013
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Trace detection of cyanide is studied based on the Ag nanoplate-built hollow microsphere array and its surface enhanced Raman scattering (SERS) effect. This array was fabricated based on electro-deposition and template method under a low current density. Due to the special structure, such array is a good SERS substrate with high activity and structural stability, and good reproducibility. Such substrate was used for detection of trace amount of kalium cyanide (KCN) in water based on its SERS effect. It has been shown that the detection limit can be down to the level of 0.1 ppb. There exists a good linear double-logarithm relation between the Raman signal and the KCN concentration in water in the range from 0.1 ppb to 1 ppm. In addition, it has been found that the suitable laser power for Raman excitation is crucial to trace detection of KCN molecules. This work is of importance in the practical application in device-design based on the SERS effect of noble metal micro/nano-structured arrays.
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Histone deacetylase inhibitors: an attractive strategy for cancer therapy.
Curr. Med. Chem.
PUBLISHED: 01-02-2013
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Histone deacetylases are able to catalyze the hydrolysis of N-acetyl lysine residues of histones which package chromosomal DNA. Therefore they play an important role in mediating gene expression and cell proliferation. HDAC inhibitors have not only shown promise as antiparasitic, antineurodegenerative, antirheumatologic agents and immunosuppressant, but as potent anticancer agents by inducing cell cycle arrest, differentiation and apoptosis. This review highlights recent development in design, synthesis and biological evaluation of HDAC inhibitors for cancer therapy.
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Tunable surface plasmon resonance and strong SERS performances of Au opening-nanoshell ordered arrays.
ACS Appl Mater Interfaces
PUBLISHED: 12-21-2011
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Au opening-nanoshell ordered arrays with tunable local surface plasmon resonance (SPR) property have been fabricated based on sputtering deposition onto monolayer colloidal crystal. The changes in local SPR peak for the arrays can be well tuned from visible to near-infrared region with decreasing of the spacing between two neighbor opening-nanoshells. It has been revealed that the changes of SPR peak originate from the electromagnetic coupling between two adjacent Au opening-nanoshells. This study is important to design and fabricate surface-enhanced Raman scattering substrates with high activity and practical application.
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Statistical potential for modeling and ranking of protein-ligand interactions.
J Chem Inf Model
PUBLISHED: 11-21-2011
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Applications in structural biology and medicinal chemistry require protein-ligand scoring functions for two distinct tasks: (i) ranking different poses of a small molecule in a protein binding site and (ii) ranking different small molecules by their complementarity to a protein site. Using probability theory, we developed two atomic distance-dependent statistical scoring functions: PoseScore was optimized for recognizing native binding geometries of ligands from other poses and RankScore was optimized for distinguishing ligands from nonbinding molecules. Both scores are based on a set of 8,885 crystallographic structures of protein-ligand complexes but differ in the values of three key parameters. Factors influencing the accuracy of scoring were investigated, including the maximal atomic distance and non-native ligand geometries used for scoring, as well as the use of protein models instead of crystallographic structures for training and testing the scoring function. For the test set of 19 targets, RankScore improved the ligand enrichment (logAUC) and early enrichment (EF(1)) scores computed by DOCK 3.6 for 13 and 14 targets, respectively. In addition, RankScore performed better at rescoring than each of seven other scoring functions tested. Accepting both the crystal structure and decoy geometries with all-atom root-mean-square errors of up to 2 Å from the crystal structure as correct binding poses, PoseScore gave the best score to a correct binding pose among 100 decoys for 88% of all cases in a benchmark set containing 100 protein-ligand complexes. PoseScore accuracy is comparable to that of DrugScore(CSD) and ITScore/SE and superior to 12 other tested scoring functions. Therefore, RankScore can facilitate ligand discovery, by ranking complexes of the target with different small molecules; PoseScore can be used for protein-ligand complex structure prediction, by ranking different conformations of a given protein-ligand pair. The statistical potentials are available through the Integrative Modeling Platform (IMP) software package (http://salilab.org/imp) and the LigScore Web server (http://salilab.org/ligscore/).
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Effect of white matter anisotropy in modeling electroconvulsive therapy.
Conf Proc IEEE Eng Med Biol Soc
PUBLISHED: 08-29-2011
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White matter in the brain exhibits strong anisotropic conductivity. Modeling studies on electroencephalography have found that such anisotropic conductivity greatly influences the estimated dipole source. In this study, we made a detailed comparison of the effects of conductivity anisotropy using a computational model of electroconvulsive therapy (ECT). The human head model was a high resolution finite element model generated from MRI scans, implemented with tissue heterogeneity and an excitable neural model incorporated in the brain. Results showed that anisotropy in conductivity had minimal effects on the location of the brain region that was maximally activated, but it had relatively large effects on deep brain structures.
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Cross-linguistic comparison of frequency-following responses to voice pitch in American and Chinese neonates and adults.
Ear Hear
PUBLISHED: 05-06-2011
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Cross-language studies, as reflected by the scalp-recorded frequency-following response (FFR) to voice pitch, have shown the influence of dominant linguistic environments on the encoding of voice pitch at the brainstem level in normal-hearing adults. Research questions that remained unanswered included the characteristics of the FFR to voice pitch in neonates during their immediate postnatal period and the relative contributions of the biological capacities present at birth versus the influence of the listeners postnatal linguistic experience. The purpose of this study was to investigate the characteristics of FFR to voice pitch in neonates during their first few days of life and to examine the relative contributions of the "biological capacity" versus "linguistic experience" influences on pitch processing in the human brainstem.
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Regulation of REG? cellular distribution and function by SUMO modification.
Cell Res.
PUBLISHED: 03-29-2011
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Discovery of emerging REG?-regulated proteins has accentuated the REG?-proteasome as an important pathway in multiple biological processes, including cell growth, cell cycle regulation, and apoptosis. However, little is known about the regulation of the REG?-proteasome pathway. Here we demonstrate that REG? can be SUMOylated in vitro and in vivo by SUMO-1, SUMO-2, and SUMO-3. The SUMO-E3 protein inhibitor of activated STAT (PIAS)1 physically associates with REG? and promotes SUMOylation of REG?. SUMOylation of REG? was found to occur at multiple sites, including K6, K14, and K12. Mutation analysis indicated that these SUMO sites simultaneously contributed to the SUMOylation status of REG? in cells. Posttranslational modification of REG? by SUMO conjugation was revealed to mediate cytosolic translocation of REG? and to cause increased stability of this proteasome activator. SUMOylation-deficient REG? displayed attenuated ability to degrade p21(Waf//Cip1) due to reduced affinity of the REG? SUMOylation-defective mutant for p21. Taken together, we report a previously unrecognized mechanism regulating the activity of the proteasome activator REG?. This regulatory mechanism may enable REG? to function as a more potent factor in protein degradation with a broader substrate spectrum.
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Ag nanosheet-assembled micro-hemispheres as effective SERS substrates.
Chem. Commun. (Camb.)
PUBLISHED: 12-23-2010
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Large-scale Ag nanosheet-assembled micro-hemispheres, with sufficient hot spots on their surfaces, have been achieved on an indium tin oxide substrate via electrodeposition. Surface-enhanced Raman scattering (SERS) measurements demonstrate that the Ag nanosheet-assembled micro-hemispheres can serve as sensitive and reproducible SERS substrates.
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[Effect of brominated furanones on biofilm formation of Escherichia coli on polyvinyl chloride material].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 08-11-2010
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To study the influence of brominated furanones on the biofilm formation of Escherichia coli on the polyvinyl chloride (PVC) material, and to provide new ideas for the research of surface modification of materials and clinical treatment of biomaterial centered infection.
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[Expression of PAH-DNA adducts in lung tissues of Xuanwei female lung cancer patients].
Zhongguo Fei Ai Za Zhi
PUBLISHED: 08-04-2010
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The coal-fired pollution in Xuanwei area has been considered to be local main reason for high incidence of female lung cancer. The aim of this study is to explore the expression of PAH-DNA adducts in lung tissues of Xuanwei female lung cancer patients and to explore the relationship between the large number of coal-fired pollution PAHs materials and the high incidence of Xuanwei female lung cancer.
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[Research on fast track surgery application in lung cancer surgery].
Zhongguo Fei Ai Za Zhi
PUBLISHED: 08-03-2010
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Fast track surgery (FTS) is a systematical method to accelerate the recovery of surgical patients by reducing the physical and mental trauma stress of them. The research is to investigate the feasibility of FTS application in lung cancer surgery.
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Comparative analysis of REG{gamma} expression in mouse and human tissues.
J Mol Cell Biol
PUBLISHED: 05-21-2010
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The REGgamma proteasome has been reported as a shortcut to destruction of proteins. However, the physiological functions of REGgamma are largely unknown. To understand the potential biological roles of REGgamma associated with different tissues or cell types, we performed systematic analysis of REGgamma gene expression in 20 different tissues from mice, followed by validation of protein expression in mouse tissues and bioinformatic analysis of REGgamma gene expression profiles in selected human tissues. Comparative analysis of REGgamma distribution in different tissues from wild-type and REGgamma knockout mice indicates that REGgamma is present in many tissues and is specifically expressed in some cell types. The highest expression of REGgamma is in the testis and unique expression features of REGgamma are revealed in a subset of neurons, including retinal ganglion cells and Purkinje cells. It is also expressed in reproductive and gastro-intestinal organs. These expressed patterns suggest potentially important functions for REGgamma in the nervous system, reproductive system and in cells with proliferative capacity. Consistent with the importance of its expression in reproductive tissue, REGgamma deficiency results in dose-dependent reduction in litter size.
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The synthesis of beta-SiC nanoparticles by high-energy mechanical ball milling and their photoluminescence properties.
J Nanosci Nanotechnol
PUBLISHED: 04-02-2010
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We succeeded in the synthesis of single-phase beta-SiC nanoparticles via simple and low-cost high-energy mechanical ball milling of a silicon and graphite mixture at ambient temperature. The synthesis products were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM) and selected area electron diffraction (SAED). The results show that starting graphite and silicon mixture reacted completely into beta-SiC nanoparticles with an average grain size of approximately 8 nm after being milled for 20 h, and the grain size gradually decreased as milling time increased from 20 to 60 h but remained basically unchanged above 60 h. The agglomeration problem of the beta-SiC nanoparticles synthesized by ball milling was resolved to a great extent by the introduction of 2 wt% NH4Cl to the initial Si-C mixture. Under 325 nm excitation, a stable and intensive broad emission peak at 387 nm was observed in the photoluminescence (PL) spectrum of the synthetic nanoparticles, and this emission shows an obvious blueshift of bandgap.
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General synthesis of 2D ordered hollow sphere arrays based on nonshadow deposition dominated colloidal lithography.
Langmuir
PUBLISHED: 02-06-2010
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A general strategy, nonshadow deposition dominated colloidal lithography (NSCL), was proposed for the synthesis of two-dimensional (2D) ordered hollow sphere arrays of conductive materials. Gold, polypyrrole, CdS, and ZnO were taken as model materials to demonstrate the NSCL strategy, and built as 2D hollow sphere arrays successfully. In this strategy, a thin gold coating is first introduced on a polystyrene sphere (PS) colloidal monolayer via ion-sputtering deposition, and a hollow sphere array can thus be obtained by further electrochemical deposition on such a monolayer and by subsequent removal of PSs. The proposed strategy is flexible and facile to control the microstructure and size of the hollow sphere array, and the features are as follows: (i) controllable shell of the hollow sphere from single-layer to multilayer with single or multiple compositions, (ii) tunable morphology from simple structure to hierarchical micro/nanostructure, and (iii) changeable arrangement of hollow spheres from close-packing to non-close-packing. Besides these, the hollow sphere size and the shell thickness can also be controlled by changing the colloidal sphere and deposition time, respectively. Further investigation indicates that the success of NSCL should be owed to a key step, that is, an ion-sputtering induced nonshadow deposition surrounding the whole surfaces of colloidal spheres. This allows an equipotential face and thus homogeneous deposition surrounding the surfaces of PSs in an electrochemical deposition process, and final formation of hollow sphere structure. The 2D ordered hollow sphere arrays with controllable microstructure and size could exhibit importance both in fundamental research and in practical applications.
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Design challenges of implantable pressure monitoring system.
Front Neurosci
PUBLISHED: 01-12-2010
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Pressure in various organs and body parts, such as blood vessels, heart, brain, eyes, bladder and GI tracts, is an important indication of health. Long term, continuous pressure monitoring is critically needed for a number of applications. When combined with existing neuro-prosthetics devices, they may provide better solutions to many neural disorders. First efforts toward a long-term implantable pressure monitoring system were initiated more than 40 years ago. However, a reliable, safe and implantable pressure sensor for long-term applications is not yet commercially available. This paper attempts to reveal the design challenges associated with the development of a long-term implantable pressure sensor.
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The current global status of Chinese materia medica.
Phytother Res
PUBLISHED: 09-30-2009
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The Chinese government has recently established a national project to improve the standards of Chinese Materia Medica (CMM) products, particularly regarding their quality control and safety evaluation, in order to promote modernization and increase international trade. In 2006, the global sales value of Chinese medicinal products increased to 20 billion US$, and the export value of CMM was up to more than 1 billion US$. However, the standard of these products still needs to be improved to meet the more stringent requirements of the international markets. Over the past decade we have witnessed the increasing growth in popularity of health foods and herbal medicinal products, especially Chinese Materia Medica products (CMM).
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2,4-Diaryl-4,6,7,8-tetrahydroquinazolin-5(1H)-one derivatives as anti-HBV agents targeting at capsid assembly.
Bioorg. Med. Chem. Lett.
PUBLISHED: 07-11-2009
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A series of novel 2,4-diaryl-4,6,7,8-tetrahydroquinazolin-5(1H)-one derivatives were designed and synthesized as potent inhibitors of HBV capsid assembly. These compounds arose from efforts to rigidify an earlier series of heteroaryldihydropyrimidines (HAPs), and compounds 12, 13, 20, 24, 30 and 32 showed potent inhibition of HBV capsid assembly, especially 24 with IC(50) value at sub-micromolar range.
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[Therapeutic efficacy of Traditional Vein Chemotherapy and Bronchial Arterial Infusion Combining with CIKs on III Stage Non-small Cell Lung Cancer.].
Zhongguo Fei Ai Za Zhi
PUBLISHED: 05-27-2009
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The therapeutic efficacy of late lung-cancer was very poor, and cytokine-induced killer cells (CIK) were paid more attention to treat non-small cell lung cancer (NSCLC). The aim of this study is to get insight into the role of bronchial arterial infusion bronchial arterial infusion (BAI) plus CIK about NSCLC by comparing therapeutic efficacy among BAI, traditional vein chemotherapy and BAI plus CIK, for late NSCLC.
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Biomechanisms for modelling cerebral cortical folding.
Med Image Anal
PUBLISHED: 01-03-2009
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Understanding the biomechanical mechanisms by which the cerebral cortex folds is a fundamental problem in neuroscience. Current mathematical models of cortical folding do not include three dimensional geometry or measurement of cortical growth in developing brains extracted from experimental data. We present two biomechanical models of cortical folding which integrate 3D geometry and information taken from MRI scans of fetal sheep brains at a number of key developmental stages. The first model utilises diffusion tensor imaging (DTI) measurements of white matter fibre orientation in the fetal sheep brains as a cue to the tension forces that may regulate folding. In the second model, tangential cortical growth is modelled by osmotic expansion of the tissue and regulated by inhomogeneous white matter rigidity as a biomechanism of cortical folding. This is based on quantitative analysis of cortical growth and inhomogeneous white matter anisotropy measured from the MRI data. We demonstrate that structural and diffusion tensor MRI can be combined with finite element modelling and an explicit growth mechanism of the cortex to create biologically meaningful models of the cortical folding process common to higher order mammals.
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Serum spleen tyrosine kinase and vascular endothelial growth factor-C levels predict lymph node metastasis of oesophageal squamous cell carcinoma.
Eur J Cardiothorac Surg
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Lymph node involvement is a key feature and an independent prognostic factor of oesophageal squamous cell carcinoma. However, an accurate and robust assay to predict the lymphatic spread of oesophageal squamous cell carcinoma is unavailable. The purpose of this study was to determine whether serum vascular endothelial growth factor-C (VEGF-C) and spleen tyrosine kinase levels are potential markers of lymph node metastasis in patients with oesophageal squamous cell carcinoma.
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On-demand nanodevice with electrical and neuromorphic multifunction realized by local ion migration.
ACS Nano
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A potential route to extend Moores law beyond the physical limits of existing materials and device architectures is to achieve nanotechnology breakthroughs in materials and device concepts. Here, we discuss an on-demand WO(3-x)-based nanoionic device where electrical and neuromorphic multifunctions are realized through externally induced local migration of oxygen ions. The device is found to possess a wide range of time scales of memorization, resistance switching, and rectification varying from volatile to permanent in a single device, and these can furthermore be realizable in both two- or three-terminal systems. The gradually changing volatile and nonvolatile resistance states are experimentally demonstrated to mimic the human brains forgetting process for short-term memory and long-term memory.We propose this nanoionic device with its on-demand electrical and neuromorphic multifunction has a unique paradigm shifting potential for the fabrication of configurable circuits, analog memories, digital-neural fused networks, and more in one device architecture.
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[In vitro toxicity of naturally occurring silica nanoparticles in C1 coal in bronchial epithelial cells].
Zhongguo Fei Ai Za Zhi
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Chinas Xuan Wei County in Yunnan Province have the worlds highest incidence of lung cancer in nonsmoking women-20 times higher than the rest of China. Previous studies showed, this high lung cancer incidence may be associated with the silica particles embedded in the production combustion from the C1 coal. The aim of this study is to separate the silica particles from production combustion from the C1 bituminous coal in Xuan Wei County of Yunnan Province, and study in vitro toxicity of naturally occurring silica particles on BEAS-2B.
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Combining MR elastography and diffusion tensor imaging for the assessment of anisotropic mechanical properties: a phantom study.
J Magn Reson Imaging
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To investigate the anisotropic elasticity of soft tissues using MR elastography (MRE) combined with diffusion tensor imaging (DTI).
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Expression, Purification, and Characterization of Ras Protein (BmRas1) from Bombyx mori.
Comp. Funct. Genomics
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The Ras subfamily is the member of small G proteins superfamily involved in cellular signal transduction. Activation of Ras signaling causes cell growth, differentiation, and survival. Bombyx mori Ras-like protein (BmRas1) may belong to the Ras subfamily. It contained an H-N-K-Ras-like domain. The BmRas1 mRNA consisted of 1459?bp. The open reading frame contained 579?bp, encoding 192 amino acids. The protein had such secondary structures as ?-helices, extended strand, and random coil. BmRas1 was expressed successfully in E. coli BL21. The recombinant protein was purified with metal-chelating affinity chromatography. The GTPase activity of purified protein was determined by FeSO(4)-(NH(4))(2)MoO(4) assay. The results showed that purified recombinant protein had intrinsic activity of GTPase. High titer polyclonal antibodies were generated by New Zealand rabbit immunized with purified protein. The gene expression features of BmRas1 at different stages and in different organs of the fifth instar larvae were analyzed by Western blot. The results showed that BmRas1 was expressed highly in three development stages including egg, pupae, and adult, but low expression in larva. BmRas1 was expressed in these tissues including head, malpighian tubule, genital gland, and silk gland. The purified recombinant protein would be utilized to further function studies of BmRas1.
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REG? is associated with multiple oncogenic pathways in human cancers.
BMC Cancer
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Recent studies suggest a role of the proteasome activator, REG?, in cancer progression. Since there are limited numbers of known REG? targets, it is not known which cancers and pathways are associated with REG?.
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What is Visualize?

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

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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