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Find video protocols related to scientific articles indexed in Pubmed.
The putative cellodextrin transporter-like protein CLP1 is involved in cellulase induction in Neurospora crassa.
J. Biol. Chem.
PUBLISHED: 11-16-2014
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Neurospora crassa recently has become a novel system to investigate cellulase induction. Here, we discovered a novel membrane protein, CLP1 (NCU05853), a putative cellodextrin transporter-like protein, that is a critical component of the cellulase induction pathway in N. crassa. Although CLP1 protein cannot transport cellodextrin, the suppression of cellulase induction by this protein was discovered on both cellobiose and Avicel. The co-disruption of the cellodextrin transporters cdt2 and clp1 in strain ?3?G formed strain CPL7. With induction by cellobiose, cellulase production was enhanced 6.9-fold in CPL7 compared with ?3?G. We also showed that the suppression of cellulase expression by CLP1 occurred by repressing the expression of cellodextrin transporters, particularly cdt1 expression. Transcriptome analysis of the hypercellulase-producing strain CPL7 showed that the cellulase expression machinery was dramatically stimulated, as were the cellulase enzyme genes including the inducer transporters and the major transcriptional regulators.
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Single-incision laparoscopic combined cholecystectomy and appendectomy.
JSLS
PUBLISHED: 11-14-2014
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Single-incision laparoscopic surgery is becoming more widely used, but few combined procedures have been reported. Herein we share our experience with single-incision laparoscopic combined cholecystectomy and appendectomy.
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Hepatitis B virus-associated glomerulonephritis in HBsAg serological-negative patients.
Eur J Gastroenterol Hepatol
PUBLISHED: 11-12-2014
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The main objective of this study is to report the clinical and pathological characteristics of hepatitis B virus (HBV)-associated glomerulonephritis (HBV-GN) in serum hepatitis B surface antigen (HBsAg)-negative patients in China. HBV-GN is caused by the HBV's attack on the kidney tissues, but definitive diagnostic criteria are still lacking. The diagnostic criteria used in China require HBsAg positivity in the serum, but research on occult HBV infection has shown that HBV infection is also found in serum HBsAg-negative patients. Clinical and pathological characterization of HBV-GN in serum HBsAg-negative patients is required.
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'How to deal with this, that and the other?' An orthopaedic surgeon's unexpected encounter with a trio of problems in an elderly man.
BMJ Case Rep
PUBLISHED: 11-12-2014
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This is the first clinical report of a psoas abscess encountered during a routine hemiarthroplasty surgery for a femoral neck fracture in a man with a recent urinary tract infection. There were no prior symptoms to suggest a psoas abscess, which was present on the same side as the hip fracture, apart from a history of recurrent urinary tract infection. The surgery had to be altered intraoperatively to that of an excision arthroplasty of the displaced non-viable femoral head along with insertion of an antibiotic-impregnated cement spacer into the hip joint. Relevant microbiological studies confirmed a methicillin-sensitive Staphylococcus aureus psoas abscess with bacteraemia in addition to Staphylococcus bacteriuria, so 6?weeks of intravenous antibiotics were started. A planned second-stage hemiarthroplasty was undertaken and the patient recovered fully without complications. Primary infection of the urinary tract by S. aureus is rare. This case serves to remind clinicians that caution must be exercised in patients with recurrent infections, especially when such infections affect organs or areas close to the intended surgery site. This warrants thorough evaluation for an occult source of infection. A psoas abscess is an unusual cause of hip pain and accurate diagnosis relies on a high index of suspicion. The antibiotic-impregnated articulating cement spacer is a useful surgical adjunct after excision arthroplasty, it not only elutes a high concentration of antibiotics in the infected field, but also facilitates second-stage arthroplasty surgery by preventing muscle and soft tissue contractures from developing.
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Construction and evaluation of rats' tolerogenic dendritic cells (DC) induced by NF-?B Decoy method.
Afr Health Sci
PUBLISHED: 10-30-2014
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To construct and evaluate rats' tolerogenic dendritic cells (DC) through induction by NF-?B Decoy method.
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Solution-Processed Organic Solar Cells Based on Dialkylthiol-Substituted Benzodithiophene Unit with Efficiency near 10%.
J. Am. Chem. Soc.
PUBLISHED: 10-27-2014
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A small molecule named DR3TSBDT with dialkylthiol-substituted benzo[1,2-b:4,5-b']dithiophene (BDT) as the central unit was designed and synthesized for solution-processed bulk-heterojunction solar cells. A notable power conversion efficiency of 9.95% (certified 9.938%) has been achieved under AM 1.5G irradiation (100 mW cm(-2)), with an average PCE of 9.60% based on 50 devices.
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Profiling Global Kinome Signatures of the Radioresistant MCF-7/C6 Breast Cancer Cells Using MRM-based Targeted Proteomics.
J. Proteome Res.
PUBLISHED: 10-24-2014
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Ionizing radiation is widely used in cancer therapy; however, cancer cells often develop radioresistance, which compromises the efficacy of cancer radiation therapy. Quantitative assessment of the alteration of the entire kinome in radioresistant cancer cells relative to their radiosensitive counterparts may provide important knowledge to define the mechanism(s) underlying tumor adaptive radioresistance and uncover novel target(s) for effective prevention and treatment of tumor radioresistance. By employing a scheduled multiple-reaction monitoring analysis in conjunction with isotope-coded ATP affinity probes, we assessed the global kinome of radioresistant MCF-7/C6 cells and their parental MCF-7 human breast cancer cells. We rigorously quantified 120 kinases, of which (1)/3 exhibited significant differences in expression levels or ATP binding affinities. Several kinases involved in cell cycle progression and DNA damage response were found to be overexpressed or hyperactivated, including checkpoint kinase 1 (CHK1), cyclin-dependent kinases 1 and 2 (CDK1 and CDK2), and the catalytic subunit of DNA-dependent protein kinase. The elevated expression of CHK1, CDK1, and CDK2 in MCF-7/C6 cells was further validated by Western blot analysis. Thus, the altered kinome profile of radioresistant MCF-7/C6 cells suggests the involvement of kinases on cell cycle progression and DNA repair in tumor adaptive radioresistance. The unique kinome profiling results also afforded potential effective targets for resensitizing radioresistant cancer cells and counteracting deleterious effects of ionizing radiation exposure.
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Application of adenosine triphosphate affinity probe and scheduled multiple-reaction monitoring analysis for profiling global kinome in human cells in response to arsenite treatment.
Anal. Chem.
PUBLISHED: 10-23-2014
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Phosphorylation of cellular components catalyzed by kinases plays important roles in cell signaling and proliferation. Quantitative assessment of perturbation in global kinome may provide crucial knowledge for elucidating the mechanisms underlying the cytotoxic effects of environmental toxicants. Here, we utilized an adenosine triphosphate (ATP) affinity probe coupled with stable isotope labeling by amino acids in cell culture (SILAC) to assess quantitatively the arsenite-induced alteration of global kinome in human cells. We constructed a SILAC-compatible kinome library for scheduled multiple-reaction monitoring (MRM) analysis and adopted on-the-fly recalibration of retention time shift, which provided better throughput of the analytical method and enabled the simultaneous quantification of the expression of ?300 kinases in two LC-MRM runs. With this improved analytical method, we conducted an in-depth quantitative analysis of the perturbation of kinome of GM00637 human skin fibroblast cells induced by arsenite exposure. Several kinases involved in cell cycle progression, including cyclin-dependent kinases (CDK1 and CDK4) and Aurora kinases A, B, and C, were found to be hyperactivated, and the altered expression of CDK1 was further validated by Western analysis. In addition, treatment with a CDK inhibitor, flavopiridol, partially restored the arsenite-induced growth inhibition of human skin fibroblast cells. Thus, sodium arsenite may confer its cytotoxic effect partly through the aberrant activation of CDKs and the resultant perturbation of cell cycle progression. Together, we developed a high-throughput, SILAC-compatible, and MRM-based kinome profiling method and demonstrated that the method is powerful in deciphering the molecular modes of action of a widespread environmental toxicant. The method should be generally applicable for uncovering the cellular pathways triggered by other extracellular stimuli.
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Nrdp1 inhibits metastasis of colorectal cancer cells by EGFR signaling-dependent MMP7 modulation.
Tumour Biol.
PUBLISHED: 09-27-2014
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The molecular mechanism underlying cancer invasiveness and metastasis of colorectal cancer (CRC) remains elusive. Here we reported a strong correlation of the levels of neuregulin receptor degradation protein-1 (Nrdp1) and matrix metalloproteinase-7 (MMP7) in CRC from the patients. We then used a human CRC line, Caco-2, to study the underlying molecular basis. We found that Nrdp1 inhibited the phosphorylation of ErB3, a key player in epidermal growth factor receptor (EGFR) signaling in Caco-2 cells, which is required for activation of MMP7 to promote cell invasion. Our findings thus reveal Nrdp1, EGFR signaling, and MMP7 as promising therapeutic targets for preventing the metastasis of CRC.
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[Mastoidectomy in the treatment of secretory otitis media].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 09-25-2014
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To investigate mastoidectomy efficacy in treating secretory otitis media.
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Transumbilical single-incision laparoscopic combined cholecystectomy and appendectomy: a retrospective comparative study.
J Laparoendosc Adv Surg Tech A
PUBLISHED: 09-22-2014
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Abstract Background: Single-incision laparoscopic surgery (SILS) developed rapidly in recent years. This report describes our initial experience on SILS combined cholecystectomy and appendectomy (SILSC&A) with a unique method of umbilical reconstruction. In addition, a retrospective comparison with conventional combined laparoscopic cholecystectomy and appendectomy (LC&A) was analyzed.
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Morphology variability of radial pulse wave during exercise.
Biomed Mater Eng
PUBLISHED: 09-18-2014
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Pulse wave contains much information on a cardiovascular system. Pulse wave variability during exercise is of great significance as it reflects more information combining with pulse wave under stationary state. This paper studied the morphology variability of radial pulse wave during exercise. Radial pulse waves were collected from 30 subjects with two pressure pulse sensors worn at the wrists of the right and left hands, respectively. Electrocardiography (ECG) was also detected synchronously. After data preprocessing and feature point extraction, the variability of several parameters of pulse wave and ECG were analyzed. It is notable that pulse rate (PR) and heart rate (HR) change synchronously. During the exercise period, both systolic phase and diastolic phase of a radial pulse shorten but the latter is more obvious. The amplitude of the dicrotic notch decreases and even turns negative. Aligning the radial pulse waveforms together, the radial pulse waveforms prior to, during and after exercise coincide with each other except for some details like the tidal wave which fades away during exercise.
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The synthesis of 5-alkyl[3,4-c]thienopyrrole-4,6-dione-based polymers using a Pd-catalyzed oxidative C-H/C-H homopolymerization reaction.
Chem. Commun. (Camb.)
PUBLISHED: 09-06-2014
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A new, simple, mild, atom economical homopolymerization method through Pd-catalyzed oxidative C-H/C-H coupling was developed for the preparation of a series of 5-alkyl[3,4-c]thienopyrrole-4,6-dione-based conjugated polymers.
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Direct chemical synthesis of L1(0)-FePtAu nanoparticles with high coercivity.
Nanoscale
PUBLISHED: 09-06-2014
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We report a facile synthesis of hard magnetic L10-FePtAu nanoparticles by coreduction of Fe(acac)3, Pt(acac)2 (acac = acetylacetonate) and gold acetate in oleylamine. In the current reaction condition, NP sizes are controlled to be 5.5 to 11.0 nm by changing the amount of Au doping. When the Au composition in the NPs is higher than 14%, the hard magnetic NPs are directly obtained without any annealing. The highest coercivity of 12.15 kOe at room temperature could be achieved for the NPs with 32% Au doping, which is much higher than the coercivities reported by the previous studies on solution-synthesized FePt nanoparticles. The reported one-pot synthesis of L10-FePtAu NPs may help to build superstrong magnets for magnetic or data-storage applications.
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Low-temperature synthesis of Mn-based mixed metal oxides with novel fluffy structures as efficient catalysts for selective reduction of nitrogen oxides by ammonia.
Chem. Commun. (Camb.)
PUBLISHED: 09-05-2014
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A series of Mn-based mixed metal oxide catalysts (Co-Mn-O, Fe-Mn-O, Ni-Mn-O) with high surface areas were prepared via low temperature crystal splitting and exhibited extremely high catalytic activity for the low-temperature selective catalytic reduction of nitrogen oxides with ammonia.
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Ethanol and isopropanol trigger rapid egress of intracellular Eimeria tenella sporozoites.
Parasitol. Res.
PUBLISHED: 08-14-2014
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Egress from host cells is a vital step of the intracellular life cycle of apicomplexan parasites such as Toxoplasma gondii. This phenomenon has attracted attentions from many research groups. Previous studies have shown that ethanol could stimulate the release of microneme proteins by elevating intracellular Ca(2+) concentration of T. gondii, resulting in the parasite egress from host cells. However, little information about egress is known on Eimeria species, the causative agent of coccidiosis in poultry and livestock. In this report, we studied the effect of ethanol and isopropanol on the egress of eimerian parasites. Eimeria tenella sporozoites cultured in primary chicken kidney cells were treated with ethanol and isopropanol, then the egressed parasites were analyzed. Ethanol and isopropanol could induce the rapid egress of E. tenella sporozoites from host cells. No substantial damage was found in parasite-egressed host cells. Compared to the freshly isolated sporozoites, the re-invading ability and reproductivity of the egressed parasites significantly decreased by 43.4 and 44.1 % individually. We also found that fewer sporozoites egressed from host cells when the parasites developed for a longer time before the alcohol treatment. These results demonstrate an in vitro egress mode different from that of T. gondii, facilitating the deciphering of the mechanisms of egress of eimerian parasites.
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Efficient enrichment of glycopeptides using metal-organic frameworks by hydrophilic interaction chromatography.
Analyst
PUBLISHED: 08-12-2014
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Selective enrichment of glycopeptides from complicated biological samples is critical for glycoproteomics to obtain the structure and glycosylation information of glycoproteins using mass spectrometry (MS), which still remains a great challenge. Hydrophilic interaction chromatography (HILIC)-based strategies have been proposed for selective isolation of glycopeptides via the interactions between the glycan of glycopeptides and the matrices. However, the application of these methods is limited by the medium selectivity of HILIC matrices. In this study, hydrophilic metal-organic frameworks (MOFs) were fabricated and used as a HILIC matrix. The cross-linked CD-MOFs (LCD-MOFs) were facilely prepared with ?-cyclodextrin as ligand and possessed nano-sized cubic structure, superior hydrophilicity, and bio-compatibility. The LCD-MOFs performance for the selective enrichment of glycopeptides from the complex biological samples were investigated with a digested mixture of human immunoglobulin G (IgG) that was used as standard samples. In the selectivity assessment, the non-glycopeptides causing ion suppression to the glycopeptides were effectively removed, the signal of glycopeptides were enhanced significantly by LCD-MOFs, and twenty glycopeptides were identified with 67 fmol of IgG digest. In addition, the resulting LCD-MOFs demonstrated the lower detection limit (3.3 fmol) with a satisfactory recovery yield (84-103%) for glycopeptide enrichment from a digest of IgG. Furthermore, a promising protocol was developed for the selective enrichment of glycopeptides from mouse liver, and 344 unique N-glycosylation sites that mapped to 290 different glycoproteins were identified in a single MS run. The results clearly demonstrated that when used in a HILIC matrix, LCD-MOFs have great potential for identifying and enriching low-abundant glycopeptides in complex biological samples.
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Removal of total cyanide in coking wastewater during a coagulation process: significance of organic polymers.
J Environ Sci (China)
PUBLISHED: 08-01-2014
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Whether a cationic organic polymer can remove more total cyanide (TCN) than a non-ionic organic polymer during the same flocculation system has not been reported previously. In this study, the effects of organic polymers with different charge density on the removal mechanisms of TCN in coking wastewater are investigated by polyferric sulfate (PFS) with a cationic organic polymer (PFS-C) or a non-ionic polymer (PFS-N). The coagulation experiments results show that residual concentrations of TCN (Fe(CN)6(3-)) after PFS-C flocculation (TCN < 0.2 mg/L) are much lower than that after PFS-N precipitation. This can be attributed to the different TCN removal mechanisms of the individual organic polymers. To investigate the roles of organic polymers, physical and structural characteristics of the flocs are analyzed by FT-IR, XPS, TEM and XRD. Owing to the presence of N+ in PFS-C, Fe(CN)6(3-) and negative flocs (Fe(CN)6(3-) adsorbed on ferric hydroxides) can be removed via charge neutralization and electrostatic patch flocculation by the cationic organic polymer. However, non-ionic N in PFS-N barely reacts with cyanides through sweeping or bridging, which indicates that the non-ionic polymer has little influence on TCN removal.
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Effect of chromosomal polymorphisms of different genders on fertilization rate of fresh IVF-ICSI embryo transfer cycles.
Reprod. Biomed. Online
PUBLISHED: 07-10-2014
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To explore whether chromosomal polymorphisms of different genders affect outcomes of fresh IVF and intracytoplasmic sperm injection (ICSI) embryo transfer cycles differently, 37 couples with chromosomal polymorphisms were identified out of 614 infertile couples undergoing IVF-ICSI treatments. Group 1 included 20 couples in which only the male carried chromosomal polymorphisms; group 2 included 17 couples with female carriers only; group 3 included 19 infertile couples with normal karyotypes randomly selected as controls. A significantly lower fertilization rate was found in group 1 compared with groups 2 and 3 (56.68% in Group 1, 78.02% in group 2 and 71.74% in group 3; group 1 versus group 2, P < 0.001; group 1 versus group 3, P = 0.001; respectively). When stratified according to fertilization method, the fertilization rate in IVF cycles of group 1 was significantly lower than group 3 (50.00% in Group 1, 73.89% in Group 3, P < 0.001). Fertilization rates in ICSI cycles between groups 1 and 3 were not significantly different. This study suggests that male chromosomal polymorphisms adversely influence fertilization rates of IVF cycles. The use of ICSI may improve the success of infertility treatment by increasing the fertilization rate for men with chromosomal polymorphisms.
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Ultrahigh-density sub-10 nm nanowire array formation via surface-controlled phase separation.
Nano Lett.
PUBLISHED: 06-30-2014
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We present simple, self-assembled, and robust fabrication of ultrahigh density cobalt nanowire arrays. The binary Co-Al and Co-Si systems phase-separate during physical vapor deposition, resulting in Co nanowire arrays with average diameter as small as 4.9 nm and nanowire density on the order of 10(16)/m(2). The nanowire diameters were controlled by moderating the surface diffusivity, which affected the lateral diffusion lengths. High resolution transmission electron microscopy reveals that the Co nanowires formed in the face-centered cubic structure. Elemental mapping showed that in both systems the nanowires consisted of Co with undetectable Al or Si and that the matrix consisted of Al with no distinguishable Co in the Co-Al system and a mixture of Si and Co in the Co-Si system. Magnetic measurements clearly indicate anisotropic behavior consistent with shape anisotropy. The dynamics of nanowire growth, simulated using an Ising model, is consistent with the experimental phase and geometry of the nanowires.
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Facile fabrication of a near-infrared responsive nanocarrier for spatiotemporally controlled chemo-photothermal synergistic cancer therapy.
Nanoscale
PUBLISHED: 06-24-2014
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Remote-controlled nanocarriers for drug delivery are of great promise to provide timely, sensitive and spatiotemporally selective treatments for cancer therapy. Due to convenient and precise manipulation, deep penetration through tissues and excellent biocompatibility, near-infrared (NIR) irradiation is a preferred external stimulus for triggering the release of loaded drugs. In this work, for spatiotemporally controlled chemo-photothermal synergistic cancer therapy, a NIR responsive nanocarrier was fabricated using reduced graphene oxide nanosheets (rNGO) decorated with mesoporous silica shell and the subsequent functionalization of the thermoresponsive polymer brushes (pNIPAM-co-pAAm) at the outlet of the silica pore channels. rNGO, which combined with the mesoporous silica shell provide a high loading capacity for anticancer drugs (doxorubicin, DOX), was assigned to sense NIR irradiation for the manipulation of pNIPAM-co-pAAm valve to control the diffusion of loaded DOX. Under NIR irradiation, rNGO would generate heat, which could not only elevate the surrounding temperature over the low critical solution temperature (LCST) of pNIPAM-co-pAAm to open the thermoresponsive polymer valve and promote the diffusion of DOX, but also kill the cancer cells through the hypothermia effect. By manipulating NIR irradiation, the nanocarrier exhibited efficiently controlled release of loaded DOX both in the buffer and in living HeLa cells (the model cancer cells), providing powerful and site-targeted treatments, which can be attributed to synergistic effects of chemo-photothermal therapy. To sum up, this novel nanocarrier is an excellent drug delivery platform in remote-controlled chemo-photothermal synergistic cancer therapy via NIR irradiation.
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Global discovery of protein kinases and other nucleotide-binding proteins by mass spectrometry.
Mass Spectrom Rev
PUBLISHED: 06-15-2014
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Nucleotide-binding proteins, such as protein kinases, ATPases and GTP-binding proteins, are among the most important families of proteins that are involved in a number of pivotal cellular processes. However, global study of the structure, function, and expression level of nucleotide-binding proteins as well as protein-nucleotide interactions can hardly be achieved with the use of conventional approaches owing to enormous diversity of the nucleotide-binding protein family. Recent advances in mass spectrometry (MS) instrumentation, coupled with a variety of nucleotide-binding protein enrichment methods, rendered MS-based proteomics a powerful tool for the comprehensive characterizations of the nucleotide-binding proteome, especially the kinome. Here, we review the recent developments in the use of mass spectrometry, together with general and widely used affinity enrichment approaches, for the proteome-wide capture, identification and quantification of nucleotide-binding proteins, including protein kinases, ATPases, GTPases, and other nucleotide-binding proteins. The working principles, advantages, and limitations of each enrichment platform in identifying nucleotide-binding proteins as well as profiling protein-nucleotide interactions are summarized. The perspectives in developing novel MS-based nucleotide-binding protein detection platform are also discussed. © 2014 Wiley Periodicals, Inc. Mass Spec Rev.
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Multivariate lesion-symptom mapping using support vector regression.
Hum Brain Mapp
PUBLISHED: 06-06-2014
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Lesion analysis is a classic approach to study brain functions. Because brain function is a result of coherent activations of a collection of functionally related voxels, lesion-symptom relations are generally contributed by multiple voxels simultaneously. Although voxel-based lesion-symptom mapping (VLSM) has made substantial contributions to the understanding of brain-behavior relationships, a better understanding of the brain-behavior relationship contributed by multiple brain regions needs a multivariate lesion-symptom mapping (MLSM). The purpose of this artilce was to develop an MLSM using a machine learning-based multivariate regression algorithm: support vector regression (SVR). In the proposed SVR-LSM, the symptom relation to the entire lesion map as opposed to each isolated voxel is modeled using a nonlinear function, so the intervoxel correlations are intrinsically considered, resulting in a potentially more sensitive way to examine lesion-symptom relationships. To explore the relative merits of VLSM and SVR-LSM we used both approaches in the analysis of a synthetic dataset. SVR-LSM showed much higher sensitivity and specificity for detecting the synthetic lesion-behavior relations than VLSM. When applied to lesion data and language measures from patients with brain damages, SVR-LSM reproduced the essential pattern of previous findings identified by VLSM and showed higher sensitivity than VLSM for identifying the lesion-behavior relations. Our data also showed the possibility of using lesion data to predict continuous behavior scores. Hum Brain Mapp 35:5861-5876, 2014. © 2014 Wiley Periodicals, Inc.
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Crucial enzymes in the hydroxylated triacylglycerol-ricinoleate biosynthesis pathway of castor bean.
Curr. Protein Pept. Sci.
PUBLISHED: 05-26-2014
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Castor bean (Ricinus communis L.) is an important oilseed crop for the rich hydroxylated triacylglycerol (TAG)-ricinoleate which is a raw material with wide applications in industry. Hydroxylated TAG synthesis occurs through complicated pathways among multiple subcellular organelles. Some crucial enzymes have been identified in previous studies. After analyzing the available castor tissue-specific transcriptome sequencing data and comparing the classic pathways in other plants, a possible de novo biosynthesis pathway for the hydroxylated TAG has been revealed. In this study, some other crucial enzymes were ascertained and their expression levels were characterized and pinpointed into the pathways in castor. Several key enzymes were analyzed in terms of structure, biofunction prediction and similarity of expression pattern mechanisms, aiming to give an insight on the better understandings of the molecular knowledge for this oil-rich plant and the crucial enzyme performances in the hydroxylated triacylglycerol-ricinoleate biosynthesis pathways.
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Combined detection of Gab1 and Gab2 expression predicts clinical outcome of patients with glioma.
Med. Oncol.
PUBLISHED: 05-25-2014
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Grb2-associated binder 1 (Gab1) and Gab2 play important roles in cancer cell signaling. In particular, it has been demonstrated that the upregulation of Gab2 may be correlated with the World Health Organization (WHO) grade of gliomas and that patients with high Gab2 expression levels exhibited shorter survival time. However, the prognostic value of combined expression of Gab1 and Gab2 has not been explored. Gab1 and Gab2 expression in human gliomas and non-neoplastic brain tissues was measured by immunohistochemistry. Both the expression levels of Gab1 and Gab2 proteins in glioma tissues were significantly higher than those in non-neoplastic brain tissues (both P < 0.001). In addition, the overexpression of Gab1 and Gab2 proteins were both significantly associated with advanced WHO grades (both P < 0.001) and low KPS (both P = 0.01). Moreover, the overall survival of patients with high Gab1 protein expression or high Gab2 protein expression was obviously lower than those with low expressions (both P < 0.001). Notably, glioma patients with combined overexpression of Gab1 and Gab2 proteins (Gab1-high/Gab2-high) had shortest overall survival (P < 0.001). Furthermore, multivariate analysis showed that Gab1 expression (P = 0.01), Gab2 expression (P = 0.02), and combined expression of Gab1 and Gab2 (Gab1/Gab2, P = 0.006) were all independent prognostic factors for overall survival in glioma patients. Gab1 and Gab2 proteins are differentially expressed in glioma patients and closely correlated with the biological behavior of this malignancy. Combination of Gab1 and Gab2 expression may represent a promising biomarker for prognostication of human gliomas.
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Synthesis of novel perphenylcarbamated ?-cyclodextrin based chiral stationary phases via thiol-ene click chemistry.
Electrophoresis
PUBLISHED: 05-17-2014
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Novel cyclodextrin (CD) chiral stationary phases (CD-CSPs) with well-defined structure have been successfully synthesized by immobilization of mono/di(10-undecenoyl)-perphenylaminocarbonyl ?-CD on the 3-mercaptopropyl functionalized silica gel via thiol-ene click chemistry. The phenyl carbamate groups on the rims of CD extended the cavity of CD-CSPs, which facilitated the formation of inclusion complex with various types of racemic compounds under RP mode, and also improved the ?-? stacking interaction, dipole-dipole interaction, and hydrogen bonding interaction with racemic compounds under normal phase mode. Fifteen racemic compounds were successfully separated on this CD-CSP with HPLC, and the chromatographic results also demonstrated that thiol-ene click chemistry affords a facile approach for preparation of CSPs.
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Effects of pulsed electromagnetic fields on the expression of NFATc1 and CAII in mouse osteoclast-like cells.
Aging Clin Exp Res
PUBLISHED: 05-06-2014
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Pulsed electromagnetic fields (PEMF) have proven to be an effective noninvasive method in the prevention and treatment of osteoporosis. This study evaluated the effects of PEMF on the expression of the NFATc1, CAII and RANK genes in mouse osteoclast-like cells.
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Ultrasensitive flow sensing of a single cell using graphene-based optical sensors.
Nano Lett.
PUBLISHED: 05-06-2014
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On the basis of the polarization-dependent absorption of graphene under total internal reflection, we designed a graphene-based optical refractive index sensor with high resolution of 1.7 × 10(-8) and sensitivity of 4.3 × 10(7) mV/RIU, as well as an extensive dynamic range. This highly sensitive graphene optical sensor enables label-free, live-cell, and highly accurate detection of a small quantity of cancer cells among normal cells at the single-cell level and the simultaneous detection and distinction of two cell lines without separation. It provides an accurate statistical distribution of normal and cancer cells with fewer cells. This facile and highly sensitive sensing refractive index may expand the practical applications of the biosensor.
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High p-Smad2 expression in stromal fibroblasts predicts poor survival in patients with clinical stage I to IIIA non-small cell lung cancer.
World J Surg Oncol
PUBLISHED: 04-28-2014
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Increasing evidence indicates that the TGF?/Smad signaling pathway plays a prominent role in tumor initiation, progression, and metastasis. Therefore, we investigate the expression of p-Smad2 in surgical resection specimens from non-small cell lung cancer, and evaluate the prognostic significance of p-Smad2 expression in stromal fibroblasts and cancer cells for patients with clinical stage I to IIIA non-small cell lung cancer.
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Sequential enrichment with titania-coated magnetic mesoporous hollow silica microspheres and zirconium arsenate-modified magnetic nanoparticles for the study of phosphoproteome of HL60 cells.
J Chromatogr A
PUBLISHED: 04-25-2014
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As one of the most important types of post-translational modifications, reversible phosphorylation of proteins plays crucial roles in a large number of biological processes. However, owing to the relatively low abundance and dynamic nature of phosphorylation and the presence of the unphosphorylated peptides in large excess, phosphopeptide enrichment is indispensable in large-scale phosphoproteomic analysis. Metal oxides including titanium dioxide have become prominent affinity materials to enrich phosphopeptides prior to their analysis using liquid chromatography-mass spectrometry (LC-MS). In the current study, we established a novel strategy, which encompassed strong cation exchange chromatography, sequential enrichment of phosphopeptides using titania-coated magnetic mesoporous hollow silica microspheres (TiO2/MHMSS) and zirconium arsenate-modified magnetic nanoparticles (ZrAs-Fe3O4@SiO2), and LC-MS/MS analysis, for the proteome-wide identification of phosphosites of proteins in HL60 cells. In total, we were able to identify 11,579 unique phosphorylation sites in 3432 unique proteins. Additionally, our results suggested that TiO2/MHMSS and ZrAs-Fe3O4@SiO2 are complementary in phosphopeptide enrichment, where the two types of materials displayed preferential binding of peptides carrying multiple and single phosphorylation sites, respectively.
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Sulfur-infiltrated graphene-based layered porous carbon cathodes for high-performance lithium-sulfur batteries.
ACS Nano
PUBLISHED: 04-23-2014
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Because of advantages such as excellent electronic conductivity, high theoretical specific surface area, and good mechanical flexibility, graphene is receiving increasing attention as an additive to improve the conductivity of sulfur cathodes in lithium-sulfur (Li-S) batteries. However, graphene is not an effective substrate material to confine the polysulfides in cathodes and stable the cycling. Here, we designed and synthesized a graphene-based layered porous carbon material for the impregnation of sulfur as cathode for Li-S battery. In this composite, a thin layer of porous carbon uniformly covers both surfaces of the graphene and sulfur is highly dispersed in its pores. The high specific surface area and pore volume of the porous carbon layers not only can achieve a high sulfur loading in highly dispersed amorphous state, but also can act as polysulfide reservoirs to alleviate the shuttle effect. When used as the cathode material in Li-S batteries, with the help of the thin porous carbon layers, the as-prepared materials demonstrate a better electrochemical performance and cycle stability compared with those of graphene/sulfur composites.
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Nitrogen-doped graphene materials for supercapacitor applications.
J Nanosci Nanotechnol
PUBLISHED: 04-23-2014
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Development of advanced functional materials for energy conversion and storage technologies play a key role in solving the problems of the rapid depletion of fossil fuels and increasingly worsened environmental pollution caused by vast fossil-fuel consumption. Supercapacitors (SCs), also known as ultracapacitors, which store energy based on either ion adsorption or fast/reversible faradaic reactions, are supposed to be a promising candidate for alternative energy storage devices due to their high rate capability, pulse power supply, long cycle life, simple principles, high dynamics of charge propagation, and low maintenance cost. The performance of supercapacitors highly depends on the properties of electrode materials. Nitrogen-doped graphene (NG)-based materials exhibit great potential for application in supercapacitors because of their unique structure and excellent intrinsic physical properties, such as large surface area with appropriate pore structure, controllable two- or three-dimensional morphology, and extraordinarily electrical conductivity. In this review, we provide a brief summary of recent research progress on NG-based electrode materials for SCs, including the various synthesis methods and the mechanisms of electrochemical performance enhancement.
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[The fusion protein of cytoplasmic transduction peptide (CTP)-HBcAg18-27-Tapasin enhances specific immune response to hepatitis B virus and inhibits viral replication in transgenic mice].
Zhonghua Gan Zang Bing Za Zhi
PUBLISHED: 04-12-2014
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To investigate the effect of protein transduction domain-hepatitis B virus core antigen (CTP-HBcAg18-27)-Tapasin fusion protein-induced specific cytotoxic T lymphocyte (CTL) response on hepatitis B virus (HBV) replication in HBV transgenic mice.
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Comprehensive characterization of (S)GTP-binding proteins by orthogonal quantitative (S)GTP-affinity profiling and (S)GTP/GTP competition assays.
Anal. Chem.
PUBLISHED: 04-11-2014
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Thiopurine drugs are widely used as antileukemic drugs and immunosuppressive agents, and 6-thioguanosine triphosphate ((S)GTP) is a major metabolite for these drugs. Recent studies have suggested that thiopurine drugs may exert their cytotoxic effects partly through binding of (S)GTP to a GTP-binding protein, Rac1. However, it remains unclear whether (S)GTP can also bind to other cellular proteins. Here, we introduced an orthogonal approach, encompassing nucleotide-affinity profiling and nucleotide-binding competition assays, to characterize comprehensively (S)GTP-binding proteins along with the specific binding sites from the entire human proteome. With the simultaneous use of (S)GTP and GTP affinity probes, we identified 165 (S)GTP-binding proteins that are involved in several different biological processes. We also examined the binding selectivities of these proteins toward (S)GTP and GTP, which allowed for the revelation of the relative binding affinities of the two nucleotides toward the nucleotide-binding motif sequence of proteins. Our results suggest that (S)GTP mainly targets GTPases, with strong binding affinities observed for multiple heterotrimeric G proteins. We also demonstrated that (S)GTP binds to several cyclin-dependent kinases (CDKs), which may perturb the CDK-mediated phosphorylation and cell cycle progression. Together, this represents the first comprehensive characterization of (S)GTP-binding property for the entire human proteome. We reason that a similar strategy can be generally employed for the future characterization of the interaction of other modified nucleotides with the global proteome.
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Monodisperse MPt (M = Fe, Co, Ni, Cu, Zn) nanoparticles prepared from a facile oleylamine reduction of metal salts.
Nano Lett.
PUBLISHED: 04-03-2014
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We report a simple, yet general, approach to monodisperse MPt (M = Fe, Co, Ni, Cu, Zn) nanoparticles (NPs) by coreduction of M(acac)2 and Pt(acac)2 (acac = acetylacetonate) with oleylamine at 300 °C. In the current reaction condition, oleylamine serves as the reducing agent, surfactant, and solvent. As an example, we describe in details the synthesis of 9.5 nm CoPt NPs with their compositions controlled from Co37Pt63 to Co69Pt31. These NPs show composition-dependent structural and magnetic properties. The unique oleylamine reduction process makes it possible to prepare MPt NPs with their physical properties and surface chemistry better rationalized for magnetic or catalytic applications.
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Atomic force microscopy study of the interaction of DNA and nanoparticles.
Adv. Exp. Med. Biol.
PUBLISHED: 04-01-2014
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The interaction between nanoparticles (NPs) and DNA plays an important role in the genotoxicity of NPs, and it is imperative to characterize the nano/DNA interactions and explore the underlying chemical mechanisms. In this chapter, we demonstrated systematic experimental approaches based on atomic force microscope (AFM), coupled with modeling computation to probe the binding activity of NPs with DNA and the putative genotoxicity. Using quantum dots (QDs) as a model NP, we examined the binding kinetics, binding isotherm, binding specificity, and binding mechanisms of NPs to DNA with the application of AFM. We further assessed the binding affinity between NPs and DNA by calculating their interaction energy on the basis of Derjaguin-Landau-Verwey-Overbeek (DLVO) models. The modeling results of binding affinity were validated by the NPs/DNA binding images experimentally derived by AFM. The investigation of the relationship between the binding affinity of five NPs ((QDs (+), QDs (-), silver NPs, hematite NPs, and gold NPs) for DNA with their inhibition effects on DNA replication indicated that NPs with a high binding affinity for DNA molecules exhibited higher inhibition on DNA replication. The methodology employed in this study can be extended to study the interaction of other NPs with DNA, which is anticipated to benefit the future design of safe NPs, as well as the toxicological investigations of NPs.
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Inter-laboratory validation of the in-vivo flow cytometric micronucleus analysis method (MicroFlow(®)) in China.
Mutat Res Genet Toxicol Environ Mutagen
PUBLISHED: 03-19-2014
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Although inter-laboratory validation efforts of the in-vivo micronucleus (MN) assay based on flow cytometry (FCM) have taken place in the EU and US, none have been organized in China. Therefore, an inter-laboratory study that included eight laboratories in China and one experienced reference laboratory in the US was coordinated to validate the in-vivo FCM MicroFlow(®) method to determine the frequency of micro-nucleated reticulocytes (MN-RETs) in rat blood. Assay reliability and reproducibility were evaluated with four known genotoxicants, and the results obtained with the FCM method were compared with the outcome of the traditional evaluation of bone-marrow micronuclei by use of microscopy. Each of the four chemicals was tested at three sites (two in China and the one US reference laboratory). After three consecutive daily exposures to a genotoxicant, blood and bone-marrow samples were obtained from rats 24h after the third dose. MN-RET frequencies were measured in 20,000 RET in blood by FCM, and micro-nucleated polychromatic erythrocyte (MN-PCE) frequencies were measured in 2,000 PCEs in bone marrow by microscopy. For both methods, each genotoxicant was shown to induce a statistically significant increase in the frequency of MN after treatment with at least one dose. Where more doses than one caused an increase, responses occurred in a dose-dependent manner. Spearman's correlation coefficient (rs) for FCM-based MN-RET vs microscopy-based MN-PCE measurements (eight experiments, 200 paired measurements) was 0.723, indicating a high degree of correspondence between methods and compartments. The rs value for replicate FCM MN-RET measurements performed at the eight collaborative laboratories was 0.940 (n=200), and between the eight FCM laboratories with the reference laboratory was 0.933 (n=200), suggesting that the automated method is very well transferable between laboratories. The FCM micronucleus analysis method is currently used in many countries worldwide, and these data support its use for evaluating the in-vivo genotoxic potential of test chemicals in China.
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Methodology to develop crash modification functions for road safety treatments with fully specified and hierarchical models.
Accid Anal Prev
PUBLISHED: 03-15-2014
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Crash modification factors (CMFs) for road safety treatments are developed as multiplicative factors that are used to reflect the expected changes in safety performance associated with changes in highway design and/or the traffic control features. However, current CMFs have methodological drawbacks. For example, variability with application circumstance is not well understood, and, as important, correlation is not addressed when several CMFs are applied multiplicatively. These issues can be addressed by developing safety performance functions (SPFs) with components of crash modification functions (CM-Functions), an approach that includes all CMF related variables, along with others, while capturing quantitative and other effects of factors and accounting for cross-factor correlations. CM-Functions can capture the safety impact of factors through a continuous and quantitative approach, avoiding the problematic categorical analysis that is often used to capture CMF variability. There are two formulations to develop such SPFs with CM-Function components - fully specified models and hierarchical models. Based on sample datasets from two Canadian cities, both approaches are investigated in this paper. While both model formulations yielded promising results and reasonable CM-Functions, the hierarchical model was found to be more suitable in retaining homogeneity of first-level SPFs, while addressing CM-Functions in sub-level modeling. In addition, hierarchical models better capture the correlations between different impact factors.
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Impact of the electron-transport layer on the performance of solution-processed small-molecule organic solar cells.
ChemSusChem
PUBLISHED: 03-13-2014
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Although the performance of polymer solar cells has been improved significantly recently through careful optimization with different interlayers for the same materials, more improvement is needed in this respect for small-molecule-based solar cells, particularly for the electron-transport layers (ETLs). In this work, three different solution-processed ETLs, PFN, ZnO nanoparticles, and LiF, were investigated and compared in the performance of small-molecule-based devices, and power conversion efficiencies (PCEs) of 8.32, 7.30, and 7.38% were achieved, respectively. The mechanism for the ETL-induced enhancement has been studied, and different ETLs have a significantly different impact on the device performance. The clearly improved performance of PFN is attributed to the combination of reduced bimolecular recombination and increased effective photon absorption in the active layer.
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A general strategy for site-directed enzyme immobilization by using NiO nanoparticle decorated mesoporous silica.
Chemistry
PUBLISHED: 03-13-2014
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Mesoporous materials have recently gained much attention owing to their large surface area, narrow pore size distribution, and superior pore structure. These materials have been demonstrated as excellent solid supports for immobilization of a variety of proteins and enzymes for their potential applications as biocatalysts in the chemical and pharmaceutical industries. However, the lack of efficient and reproducible methods for immobilization has limited the activity and recyclability of these biocatalysts. Furthermore, the biocatalysts are usually not robust owing to their rapid denaturation in bulk solvents. To solve these problems, we designed a novel hybrid material system, mesoporous silica immobilized with NiO nanoparticles (SBA-NiO), wherein enzyme immobilization is directed to specific sites on the pore surface of the material. This yielded the biocatalytic species with higher activity than free enzyme in solution. These biocatalytic species are recyclable with minimal loss of activity after several cycles, demonstrating an advantage over free enzymes.
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Tapasin modification on the intracellular epitope HBcAg18-27 enhances HBV-specific CTL immune response and inhibits hepatitis B virus replication in vivo.
Lab. Invest.
PUBLISHED: 03-10-2014
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HBV-specific cytotoxic T-lymphocyte (CTL) activity has a very important role in hepatitis B virus clearance. Present studies suggest that Tapasin, a endoplasmic reticulum (ER) chaperone, stabilizes the peptide-receptive MHC I conformation, allowing peptide exchange and increasing more peptides to be translocated into the ER. We have previously testified that cytoplasmic transduction peptide (CTP)-HBcAg(18-27)-Tapasin fusion protein could enter cytoplasm of dendritic cells, and enhance T cells' response to generate specific CTLs efficiently in vitro. In the present study, we evaluated specific immune responses of CTP-HBcAg(18-27)-Tapasin fusion protein in HLA-A2 transgenic mice (H-2K(b)) and anti-viral ability in HBV transgenic mice, and explored the mechanisms probably involved in. The studies showed that CTP-HBcAg(18-27)-Tapasin not only increased production of cytokine IFN-? and interleukin-2 (IL-2), compared with CTP-HBcAg(18-27), HBcAg(18-27)-Tapasin, and PBS, but also significantly induced the higher percentages of IFN-?+CD8(+) T cells and specific CTL responses in HLA-A2 transgenic mice. Moreover, enhancement of specific CTL activity induced by the fusion protein reduced HBV DNA and hepatitis B surface antigen (HBsAg) levels and decreased the expression of HBsAg and hepatitis B core antigen (HBcAg) in liver tissue of HBV transgenic mice. In addition, CTP-HBcAg(18-27)-Tapasin could upregulate the expression of JAK2, Tyk2, STAT1, and STAT4 in T lymphocytes in HLA-A2 transgenic mice splenocytes. However, there was no significant difference on the expressions of JAK1, JAK3, and STAT6 between each group. In conclusion, CTP-HBcAg(18-27)-Tapasin fusion protein could enhance not only the percentages of CTLs but also induce robust specific CTL activity and inhibits hepatitis B virus replication in vivo, which was associated with activation of the JAK/STAT signaling pathway.
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Critical evaluation and modeling of algal harvesting using dissolved air flotation.
Biotechnol. Bioeng.
PUBLISHED: 02-28-2014
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In this study, Chlorella zofingiensis harvesting by dissolved air flotation (DAF) was critically evaluated with regard to algal concentration, culture conditions, type and dosage of coagulants, and recycle ratio. Harvesting efficiency increased with coagulant dosage and leveled off at 81%, 86%, 91%, and 87% when chitosan, Al(3+) , Fe(3+) , and cetyl trimethylammonium bromide (CTAB) were used at dosages of 70, 180, 250, and 500?mg?g(-1) , respectively. The DAF efficiency-coagulant dosage relationship changed with algal culture conditions. Evaluation of the influence of the initial algal concentration and recycle ratio revealed that, under conditions typical for algal harvesting, it is possible that the number of bubbles is insufficient. A DAF algal harvesting model was developed to explain this observation by introducing mass-based floc size distributions and a bubble limitation into the white water blanket model. The model revealed the importance of coagulation to increase floc-bubble collision and attachment, and the preferential interaction of bubbles with larger flocs, which limited the availability of bubbles to the smaller sized flocs. The harvesting efficiencies predicted by the model agree reasonably with experimental data obtained at different Al(3+) dosages, algal concentrations, and recycle ratios. Based on this modeling, critical parameters for efficient algal harvesting were identified. Biotechnol. Bioeng. 2014;111: 2477-2485. © 2014 Wiley Periodicals, Inc.
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A flexible and high-voltage internal tandem supercapacitor based on graphene-based porous materials with ultrahigh energy density.
Small
PUBLISHED: 02-27-2014
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Pursuing higher working voltage and packaged energy density, an internal tandem supercapacitor has been successfully designed and fabricated based on graphene-based porous carbon hybrid material. Compared with the packaged energy density of 27.2 Wh kgcell (-1) and working voltage of 3.5 V using EMIMBF4 electrolyte for the conventional single-cell supercapacitor, the internal tandem device with the same material achieves a much higher working voltage of 7 V as well as a significantly improved energy density of 36.3 Wh kgcell (-1) (increased by 33%), which is also about 7 times of that of the state-of-art commercial supercapacitors. A flexible internal tandem device is also designed and fabricated and demonstrated similar excellent performance.
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Monomethylarsonous acid inhibited endogenous cholesterol biosynthesis in human skin fibroblasts.
Toxicol. Appl. Pharmacol.
PUBLISHED: 02-23-2014
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Human exposure to arsenic in drinking water is a widespread public health concern, and such exposure is known to be associated with many human diseases. The detailed molecular mechanisms about how arsenic species contribute to the adverse human health effects, however, remain incompletely understood. Monomethylarsonous acid [MMA(III)] is a highly toxic and stable metabolite of inorganic arsenic. To exploit the mechanisms through which MMA(III) exerts its cytotoxic effect, we adopted a quantitative proteomic approach, by coupling stable isotope labeling by amino acids in cell culture (SILAC) with LC-MS/MS analysis, to examine the variation in the entire proteome of GM00637 human skin fibroblasts following acute MMA(III) exposure. Among the ~6500 unique proteins quantified, ~300 displayed significant changes in expression after exposure with 2 ?M MMA(III) for 24 h. Subsequent analysis revealed the perturbation of de novo cholesterol biosynthesis, selenoprotein synthesis and Nrf2 pathways evoked by MMA(III) exposure. Particularly, MMA(III) treatment resulted in considerable down-regulation of several enzymes involved in cholesterol biosynthesis. In addition, real-time PCR analysis showed reduced mRNA levels of select genes in this pathway. Furthermore, MMA(III) exposure contributed to a distinct decline in cellular cholesterol content and significant growth inhibition of multiple cell lines, both of which could be restored by supplementation of cholesterol to the culture media. Collectively, the present study demonstrated that the cytotoxicity of MMA(III) may arise, at least in part, from the down-regulation of cholesterol biosynthesis enzymes and the resultant decrease of cellular cholesterol content.
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Extensive genetic diversity and low linkage disequilibrium within the COMT locus in maize exotic populations.
Plant Sci.
PUBLISHED: 02-16-2014
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The caffeic acid 3-O-methytransferase (COMT) gene is a prime candidate for cell wall digestibility improvement based on the characterization of brown midrib-3 mutants. We compared the genetic diversity and linkage disequilibrium at this locus between exotic populations sampled within the Germplasm Enhancement of Maize (GEM) project and 70 inbred lines. In total, we investigated 55 exotic COMT alleles and discovered more than 400 polymorphisms in a 2.2 kb region with pairwise nucleotide diversity (?) up to 0.017, much higher than reported ? values of various genes in inbred lines. The ratio of non-synonymous to synonymous SNPs was 3:1 in exotic populations, and significantly higher than the 1:1 ratio for inbred lines. Selection tests detected selection signature in this gene in both pools, but with different evolution patterns. The linkage disequilibrium decay in exotic populations was at least four times more rapid than for inbred lines with r²>0.1 persisting only up to 100 bp. In conclusion, the alleles sampled in the GEM Project offer a valuable genetic resource to broaden genetic variation for the COMT gene, and likely other genes, in inbred background. Moreover, the low linkage disequilibrium makes this material suitable for high resolution association analyses.
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A targeted quantitative proteomics strategy for global kinome profiling of cancer cells and tissues.
Mol. Cell Proteomics
PUBLISHED: 02-11-2014
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Kinases are among the most intensively pursued enzyme superfamilies as targets for anti-cancer drugs. Large data sets on inhibitor potency and selectivity for more than 400 human kinases became available recently, offering the opportunity to design rationally novel kinase-based anti-cancer therapies. However, the expression levels and activities of kinases are highly heterogeneous among different types of cancer and even among different stages of the same cancer. The lack of effective strategy for profiling the global kinome hampers the development of kinase-targeted cancer chemotherapy. Here, we introduced a novel global kinome profiling method, based on our recently developed isotope-coded ATP-affinity probe and a targeted proteomic method using multiple-reaction monitoring (MRM), for assessing simultaneously the expression of more than 300 kinases in human cells and tissues. This MRM-based assay displayed much better sensitivity, reproducibility, and accuracy than the discovery-based shotgun proteomic method. Approximately 250 kinases could be routinely detected in the lysate of a single cell line. Additionally, the incorporation of iRT into MRM kinome library rendered our MRM kinome assay easily transferrable across different instrument platforms and laboratories. We further employed this approach for profiling kinase expression in two melanoma cell lines, which revealed substantial kinome reprogramming during cancer progression and demonstrated an excellent correlation between the anti-proliferative effects of kinase inhibitors and the expression levels of their target kinases. Therefore, this facile and accurate kinome profiling assay, together with the kinome-inhibitor interaction map, could provide invaluable knowledge to predict the effectiveness of kinase inhibitor drugs and offer the opportunity for individualized cancer chemotherapy.
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Fusion protein of tapasin and hepatitis B core antigen 18?27 enhances T helper cell type 1/2 cytokine ratio and antiviral immunity by inhibiting suppressors of cytokine signaling family members 1/3 in hepatitis B virus transgenic mice.
Mol Med Rep
PUBLISHED: 01-31-2014
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Persistent hepatitis B virus (HBV) infection is characterized by a weak adaptive immune response, which is considered to be due to an imbalance of T helper cell types 1 and 2 (Th1/Th2). Suppressors of cytokine signaling (SOCS) family members, particularly SOCS1 and SOCS3, have been demonstrated to be important in the regulation of T cell differentiation. Previous studies by our group showed that the expressed and purified fusion protein of cytoplasmic transduction peptide (CTP) and HBV core antigen 18?27 (HBcAg18?27)?tapasin was able to enter the cytoplasm of bone marrow?derived dendritic cells (BMDCs), promoting the maturation of BMDCs and efficiently enhancing T cell immune responses in vitro. In the present study, HBcAg?specific immune responses induced by CTP?HBcAg18?27?tapasin in HBV were assessed in transgenic mice, and SOCS1 and SOCS3 were identified as negative regulators of this response. The Th1/Th2 cytokine ratio was analyzed by ELISA. The expression of T cell?specific T?box transcription factor (T?bet) and GATA?binding protein 3 (GATA?3), SOCS1 and SOCS3 were detected by real?time quantitative polymerase chain reaction and western blot analysis. The results demonstrated that CTP?HBcAg18?27?tapasin significantly increased the Th1/Th2 cytokine ratio in HBV transgenic mice. CTP?HBcAg18?27?tapasin immunization more efficiently suppressed the expression of serum hepatitis B surface antigen (HBsAg), HBV DNA as well as liver HBsAg and HBcAg in HBV transgenic mice. Furthermore, CTP?HBcAg18?27?tapasin promotes T?bet but reduces GATA?3 expression. In addition, the expression of SOCS1 and SOCS3 was significantly downregulated in the CTP?HBcAg18?27?tapasin group compared with the control groups. In conclusion, the present study demonstrated that CTP?HBcAg18?27?tapasin enhanced the Th1/Th2 cytokine ratio and antiviral immunity by suppressing SOCS1/3 in HBV transgenic mice.
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Facile preparation of core-shell magnetic metal-organic framework nanospheres for the selective enrichment of endogenous peptides.
Chemistry
PUBLISHED: 01-30-2014
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Facile preparation of core-shell magnetic metal-organic framework nanospheres by a layer-by-layer approach is presented. The nanospheres have high surface area (285.89?cm(2) ?g(-1)), large pore volume (0.18?cm(3) ?g(-1)), two kinds of mesopores (2.50 and 4.72?nm), excellent magnetic responsivity (55.65?emu?g(-1)), structural stability, and good dispersibility. The combination of porosity, hydrophobicity, and uniform magnetism was exploited for effective enrichment of peptides with simultaneous exclusion of high molecular weight proteins. The nanospheres were successfully applied in the selective enrichment of endogenous peptides in human serum.
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Silver nanowire percolation network soldered with graphene oxide at room temperature and its application for fully stretchable polymer light-emitting diodes.
ACS Nano
PUBLISHED: 01-29-2014
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Transparent conductive electrodes with high surface conductivity, high transmittance in the visible wavelength range, and mechanical compliance are one of the major challenges in the fabrication of stretchable optoelectronic devices. We report the preparation of a transparent conductive electrode (TCE) based on a silver nanowire (AgNW) percolation network modified with graphene oxide (GO). The monatomic thickness, mechanical flexibility, and strong bonding with AgNWs enable the GO sheets to wrap around and solder the AgNW junctions and thus dramatically reduce the inter-nanowire contact resistance without heat treatment or high force pressing. The GO-soldered AgNW network has a figure-of-merit sheet resistance of 14 ohm/sq with 88% transmittance at 550 nm. Its storage stability is improved compared to a conventional high-temperature annealed AgNW network. The GO-soldered AgNW network on polyethylene terephthalate films was processed from solutions using a drawdown machine at room temperature. When bent to 4 mm radius, its sheet resistance was increased by only 2-3% after 12,000 bending cycles. GO solder can also improve the stretchability of the AgNW network. Composite TCE fabricated by inlaying a GO-soldered AgNW network in the surface layer of polyurethane acrylate films is stretchable, by greater than 100% linear strain without losing electrical conductivity. Fully stretchable white polymer light-emitting diodes (PLEDs) were fabricated for the first time, employing the stretchable TCE as both the anode and cathode. The PLED can survive after 100 stretching cycles between 0 and 40% strain and can be stretched up to 130% linear strain at room temperature.
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Alpha-Fe(2)O(3) elicits diameter-dependent effects during exposure to an in vitro model of the human placenta.
Cell Biol. Toxicol.
PUBLISHED: 01-25-2014
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Iron oxide nanoparticles offer unique possibilities due to the change in their physico-chemical parameters when synthesized on the nanoscale (10(-9) m) compared to their bulk forms. While novel uses exist for these materials when synthesized as nanoparticles, their unintended effects on the human body and specifically during pregnancy remain ill defined. In this study, an iron oxide nanoparticle, ?-Fe2O3, was employed and the potential toxicity due to exposure was assessed in the widely used model human placental cell line BeWo b30. These cells were grown as epithelia, and subsequently assessed for their epithelial integrity, reactive oxygen species production and cellular viability, ultrastructural and morphological disruption, and genotoxicity as a result of exposure to ?-Fe2O3 nanoparticles. Transepithelial electrical resistance indicated that exposure to the large (50 and 78 nm), but not small (15 nm) diameter particles of ?-Fe2O3 nanomaterial resulted in leakiness of the epithelium. Exposure to the large diameters of 50 and 78 nm resulted in increases in cell death and reactive oxygen species. Disruption of junctional integrity as monitored by immunolocalization of the tight junction protein ZO-1 was found to occur as a consequence of exposure to large diameter NPs. It was found that there was reduction in the number of microvilli responsible for increased surface area for nutrient absorption after exposing the epithelia to large diameter NPs. Finally, genotoxicity as assessed by DNA microarray and confirmed by QPCR indicated that the large diameter particles (78 nm) induce apoptosis in these cells. These data indicate that large (50 and 78 nm), but not small (15 nm) ?-Fe2O3 nanoparticles disrupt the barrier function of this epithelium as assessed by in vitro analysis.
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Bioaccumulation of decabromodiphenyl ether (BDE209) in earthworms in the presence of lead (Pb).
Chemosphere
PUBLISHED: 01-22-2014
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BDE209 (decabromodiphenyl ether) and lead (Pb) are the main contaminants at e-waste recycling sites, and their potential toxicological effects on terrestrial organisms have received extensive attention. However, the impact on earthworms of exposure to the two chemicals remains almost unknown. Therefore, indoor incubation tests were performed on control and contaminated soil samples to determine the uptake and transformation of BDE209 in the presence of Pb for the first time. The results have demonstrated that Pb addition can affect BDE209 bioaccumulation efficiency compared with exposure to BDE209 alone. For a low BDE209 concentration (1mgkg(-1)), Pb addition barely affected the uptake of BDE209, whereas for a high BDE209 concentration (100mgkg(-1)), Pb addition elicited a complex response. Scanning electron microscope (SEM) observation indicated that a higher level of Pb (250 and 500mgkg(-1)) facilitated the uptake of BDE209 through the skin. Gas chromatography/mass spectrometry (GC/MS) analysis showed that the peak of BDE209 accumulation usually appeared in the joint exposure groups involving 10 or 100mgkg(-1) BDE209 and 250mgkg(-1) Pb, and the average bioaccumulation factor (BAF) was 0.53, which is more than 1.2 times that of single exposure to BDE209 (average=0.44). Also, the earthworms eliminated more BDE209 after 21d, and the biodegradation products were mainly BDE206 and BDE208. Furthermore, Pb addition can affect the transformation efficiency of BDE209 in earthworms, and several lower bromodiphenyl ethers can be detected. The results of these observations have provided a basic understanding of the potential ecotoxicological effects of joint PBDE and heavy metal exposure on terrestrial invertebrates.
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Can there be a place for intraoperative salvaged blood in spine tumor surgery?
Ann. Surg. Oncol.
PUBLISHED: 01-06-2014
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Intraoperative cell salvage (IOCS) has been used in musculoskeletal surgery extensively. However, it has never found its place in musculoskeletal oncologic surgery. We have conducted the first-ever study to evaluate the feasibility of IOCS in combination with a leucocyte-depletion filter (LDF) in metastatic spine tumor surgery. This was to pave the path for use of IOCS-LDF in musculoskeletal oncologic surgery.
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Preparation and characterization of an amphipathic magnetic nanosphere.
J Anal Methods Chem
PUBLISHED: 01-04-2014
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The amphipathic magnetic nanospheres were synthesized using C8 and polyethylene glycol as ligands. Their morphology, structure, and composition were characterized by transmission electron microscope, Fourier transform infrared, and elementary analysis. The prepared materials presented uniform sphere with size distribution about 200?nm. The magnetic characteristics of magnetic nanomaterials were measured by vibrating sample magnetometer. The target products had a saturation magnetization value of 50?emu?g(-1) and superparamagnetism. The adsorption capability was also studied by static tests, and the material was applied to enrich benzenesulfonamide from calf serum. The results exhibited that the C8-PEG phase owned better adsorption capability, biocompatible property, and dispersivity in aqueous samples.
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Use of intraoperative cell-salvage for autologous blood transfusions in metastatic spine tumour surgery: a systematic review.
Lancet Oncol.
PUBLISHED: 01-04-2014
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Metastatic spine tumour surgery (MSTS) and metastatic musculoskeletal tumour surgery (MMTS) are associated with substantial blood loss. Allogeneic blood transfusion is the present method used to replenish this blood. Intraoperative cell salvage (IOCS) is a viable alternative, but is contraindicated in tumour surgery because of the risk of tumour dissemination. Use of IOCS-leucocyte depletion filter (LDF) allows removal of tumour cells from blood salvaged during oncological surgery. However, no reports exist on use of IOCS in MSTS or MMTS. We systematically reviewed studies on IOCS in oncological surgery to investigate whether sufficient evidence exists to support its use in MSTS or MMTS.
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Phytochemical profiles and antioxidant activities in six species of ramie leaves.
PLoS ONE
PUBLISHED: 01-01-2014
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Increased consumption of vegetables or plant food has been associated with decreased risk of developing major chronic diseases, such as cancers, diabetes, cardiovascular diseases, and age-related functional decline. Ramie leaves are rich in phenolics and flavonoids, which have been suggested for human health benefits. Phenolic contents, flavonoid contents, phenolic compounds, and anti-cancer properties in six species of ramie leaves were analyzed by Folin-reagent method, sodium borohydride/chloranil-based assay (SBC), HPLC method and antiproliferation, cytoxicity, respectively. Antioxidant activities were measured through peroxyl radical scavenging capacity (PSC) method, oxygen radical absorbance capacity (ORAC) method, and cellular antioxidant activity (CAA). Research indicated that Boehmeria penduliflora contained the highest total phenolic content (2313.7±27.28 mg GAE/100 g FW), and flavonoid content (1682.4±27.70 mg CAE/100 g FW). Boehmeria tricuspis showed the highest PSC value (9574.8±117.63 µM vit. C equiv./100 g FW), while Boehmeria penduliflora indicated the highest ORAC value (330.44±16.88 µmol Trolox equiv./g FW). The antioxidant activities were correlated with phenolic contents and flavonoid contents. Boehmeria tricuspis had the highest antiproliferative capacity with the lowest EC?? (4.11±0.19 mg/mL). The results for the analyzed ramie for CAA were significantly different from each other (p<0.05), Boehmeria tricuspis had the highest CAA value (133.63±7.10 µmol QE/100 g). Benzoic acid, 4-coumaric acid, caffeic acid, and ferulic acid were the dominant phenolic ingredients in the ramie leaves according to HPLC analysis. Our research is the first report to study the phytochemical profiles and antioxidant activities in different species of ramie leaves for their health benefit.
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Short Peptide Tag for Covalent Protein Labeling Based on Coiled Coils.
Bioconjug. Chem.
PUBLISHED: 12-23-2013
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To label proteins covalently, one faces a trade-off between labeling a protein specifically and using a small tag. Often one must compromise one parameter for the other or use additional components, such as an enzyme, to satisfy both requirements. Here, we report a new reaction that covalently labels proteins by using engineered coiled-coil peptides. Harnessing the concept of "proximity-induced reactivity", the 21-amino-acid three-heptad peptides CCE/CCK were modified with a nucleophilic cysteine and an ?-chloroacetyl group at selected positions. When pairs of coiled coils associated, an irreversible covalent bond spontaneously formed between the peptides. The specificity of the cross-linking reaction was characterized, the probes were improved by making them bivalent, and the system was used to label a protein in vitro and receptors on the surface of mammalian cells.
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Nanoparticles Inhibit DNA Replication by Binding to DNA: Modeling and Experimental Validation.
ACS Nano
PUBLISHED: 10-09-2013
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Predictive models are beneficial tools for researchers to use in prioritizing nanoparticles (NPs) for toxicological tests, but experimental evaluation can be time-consuming and expensive, and thus, priority should be given to tests that identify the NPs most likely to be harmful. For characterization of NPs, the physical binding of NPs to DNA molecules is important to measure, as interference with DNA function may be one cause of toxicity. Here, we determined the interaction energy between 12 types of NPs and DNA based on the Derjaguin-Landau-Verwey-Overbeek (DLVO) model and then predicted the affinity of the NPs for DNA. Using the single-molecule imaging technique known as atomic force microscopy (AFM), we experimentally determined the binding affinity of those NPs for DNA. Theoretical predictions and experimental observations of the binding affinity agreed well. Furthermore, the effect of NPs on DNA replication in vitro was investigated with the polymerase chain reaction (PCR) technique. The results showed that NPs with a high affinity for DNA strongly inhibited DNA replication, whereas NPs with low affinity had no or minimal effects on DNA replication. The methodology here is expected to benefit the genotoxicological testing of NPs as well as the design of safe NPs.
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Graphene quantum dots as the hole transport layer material for high-performance organic solar cells.
Phys Chem Chem Phys
PUBLISHED: 10-08-2013
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We present an investigation of organic photovoltaic (OPV) cells with solution-processable graphene quantum dots (GQDs) as hole transport layers (HTLs). GQDs, with uniform sizes and good conductivity, are demonstrated to be excellent HTLs in both polymer solar cells (PSCs) and small-molecule solar cells (SMSCs) with the blend of poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PC61BM) and small molecule DR3TBDT:[6,6]-phenyl-C71-butyric acid methyl ester (DR3TBDT:PC71M) as the active layer, respectively. The PSCs and SMSCs based on GQDs yield power conversion efficiencies of 3.51% and 6.82%, respectively, both comparable to those of solar cells with PEDOT:PSS as the HTLs. In addition, the cells with GQDs as HTLs exhibit much more reproducible performance and longer lifetime. In light of the high stability, low cost and easy processing, these results indicate that GQDs can be potentially used to replace PEDOT:PSS for producing high-performance and stable organic photovoltaic cells.
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Influence of hydrophilic amino acids and GC-content on expression of recombinant proteins used in vaccines against foot-and-mouth disease virus in Escherichia coli.
Biotechnol. Lett.
PUBLISHED: 10-01-2013
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Epitope-based protein expression in Escherichia coli can be improved by adjusting its amino acid composition and encoding genes. To that end, we analyzed 24 recombinant epitope proteins (rEPs) that carry multiple epitopes derived from VP1 protein of foot-and-mouth disease virus. High level expression of the rEPs was attributed to a high content of Arg, Asn, Asp and Thr, a low content of Gln, Pro and Lys, a high content of hydrophilic amino acids and a higher isoelectric point value resulting from abundant Arg. It is also attributed to the appropriate guanine and cytosine content in the encoding genes. The data provide a reference for adjusting the amino acid composition in designing epitope-based proteins used in vaccines and for adjusting the synonymous codons to improve their expressions in E. coli.
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One-pot synthesis of urchin-like FePd-Fe3O4 and their conversion into exchange-coupled L1(0)-FePd-Fe nanocomposite magnets.
Nano Lett.
PUBLISHED: 09-19-2013
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We report a one-pot synthesis of urchin-like FePd-Fe3O4 nanocomposites, spherical clusters of FePd nanoparticles (NPs) with spikes of Fe3O4 nanorods (NRs), via controlled thermal decomposition of Fe(CO)5 and reduction of Pd(acac)2. The FePd NPs with sizes between 6 and 9 nm self-aggregate into 60 nm superparticles (SPs), and Fe3O4 NRs grow on the surface of these SPs. Reductive annealing at 500 °C converts the FePd-Fe3O4 into exchange-coupled nanocomposites L1(0)-FePd-Fe with their Hc tunable from 0.8 to 2.6 kOe and Ms controlled from 90 to 190 emu/g. The work provides a general approach to L1(0)-FePd-Fe nanocomposite magnets for understanding exchange coupling at the nanoscale. The concept may be extended to other magnetic nanocomposite systems and may help to build superstrong magnets for magnetic applications.
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Surface-coating-dependent dissolution, aggregation, and reactive oxygen species (ROS) generation of silver nanoparticles under different irradiation conditions.
Environ. Sci. Technol.
PUBLISHED: 09-04-2013
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Dissolution, aggregation, and reactive oxygen species (ROS) generation are three major processes that silver nanoparticles (AgNPs) undergo in aqueous environments. In this study, the effects of AgNP surface coatings on these three processes were systematically evaluated under three irradiation conditions (UV-365, UV-254, and xenon lamp) to advance knowledge on the environmental fate and photochemical kinetics of AgNPs. The AgNPs used were (a) bare-AgNPs, (b) electrostatically stabilized citrate-AgNPs, and (c) sterically stabilized polyvinylpyrrolidone-AgNPs (PVP-AgNPs), and the light exposures greatly promoted the three processes. Both the 5-h released Ag(+) concentrations and the 2.5-h aggregation rate followed the order UV-365 > xenon lamp > UV-254 for all three types of AgNPs. For all irradiation conditions, the 5-h released Ag(+) concentration was highest for bare-AgNPs, followed by PVP-AgNPs and citrate-AgNPs; the 2.5-h aggregation rate was highest for bare-AgNPs, followed by citrate-AgNPs and PVP-AgNPs, which indicated that surface coating significantly determines the process kinetics of AgNPs. Under UV-365 irradiation, the bare-AgNPs generated superoxide and hydroxyl radicals, but the citrate-AgNPs yielded only superoxide radical, and the PVP-AgNPs did not generate any ROS. This study highlights the different fates and kinetic behaviors of AgNPs during photochemical interactions, providing important insight into the environmental implications of AgNP release.
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The selective transfer of patterned graphene.
Sci Rep
PUBLISHED: 09-03-2013
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We demonstrate a selective microcleaving graphene (MG) transfer technique for the transfer of graphene patterns and graphene devices onto chosen targets using a bilayer-polymer structure and femtosecond laser microfabrication. In the bilayer-polymer structure, the first layer is used to separate the target graphene from the other flakes, and the second layer transfers the patterned graphene to the chosen targets. This selective transfer technique, which exactly transfers the patterned graphene onto a chosen target, leaving the other flakes on the original substrate, provides an efficient route for the fabrication of MG for microdevices and flexible electronics and the optimization of graphenes performance. This method will facilitate the preparation of van der Waals heterostructures and enable the optimization of the performance of graphene hybrid devices.
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Immunosuppressive effect of renal cell carcinoma on phenotype and function of dendritic cells.
Int Urol Nephrol
PUBLISHED: 08-28-2013
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Dendritic cells (DCs) play an important role in anti-renal cell carcinoma (RCC) immunity. The aim of the study was to investigate effect of mimic RCC microenvironment on phenotype and function of DCs. We isolated conditioned media (CM) from supernatants of culturing RCC cells and adjacent non-RCC cells in patients. CD14+ monocytes were obtained from healthy donors. The monocytes derived DCs were treated by RCC CM and non-RCC CM. Maturation markers CD80, CD83, CD86, and HLA-DR on DCs were analyzed using flow cytometry, while the levels of IL-10, TGF-?, and IL12p70 in supernatants were examined by ELISA. The DCs migration treated with RCC CM and non-RCC CM was investigated using transwell assay. The DCs treated and allogenic T cells were co-cultured for detecting T-cell proliferation and change of phenotype on the T cells. Our results indicated that RCC CM inhibited the up-regulation of CD80,CD83, CD86, and HLA-DR in response to LPS in treated DCs and increased IL-10 and TGF-? secretion but reduced IL12p70 production. Moreover, the migration ability of DCs treated with RCC CM was also inhibited, compared to DCs treated with adjacent non-RCC CM. In addition, T-cell proliferation was suppressed in co-culture assay with DCs treated with RCC CM; proportion CD25+Foxp3+ regulatory T cells were induced to increase. This study suggests that RCC CM can inhibit maturation of DCs and impair its function; moreover, DCs treated with RCC CM induce regulatory T cells increase, thus could contribute RCC escape from antitumor immunity.
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Navigated total knee arthroplasty: is it error-free?
Knee Surg Sports Traumatol Arthrosc
PUBLISHED: 08-21-2013
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The aim of this study was to determine whether errors do occur in navigated total knee arthroplasty (TKAs) and to study whether errors in bone resection or implantation contribute to these errors.
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High performance photovoltaic applications using solution-processed small molecules.
Acc. Chem. Res.
PUBLISHED: 07-31-2013
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Energy remains a critical issue for the survival and prosperity of humancivilization. Many experts believe that the eventual solution for sustainable energy is the use of direct solar energy as the main energy source. Among the options for renewable energy, photovoltaic technologies that harness solar energy offer a way to harness an unlimited resource and minimum environment impact in contrast with other alternatives such as water, nuclear, and wind energy. Currently, almost all commercial photovoltaic technologies use Si-based technology, which has a number of disadvantages including high cost, lack of flexibility, and the serious environmental impact of the Si industry. Other technologies, such as organic photovoltaic (OPV) cells, can overcome some of these issues. Today, polymer-based OPV (P-OPV) devices have achieved power conversion efficiencies (PCEs) that exceed 9%. Compared with P-OPV, small molecules based OPV (SM-OPV) offers further advantages, including a defined structure for more reproducible performance, higher mobility and open circuit voltage, and easier synthetic control that leads to more diversified structures. Therefore, while largely undeveloped, SM-OPV is an important emerging technology with performance comparable to P-OPV. In this Account, we summarize our recent results on solution-processed SM-OPV. We believe that solution processing is essential for taking full advantage of OPV technologies. Our work started with the synthesis of oligothiophene derivatives with an acceptor-donor-acceptor (A-D-A) structure. Both the backbone conjugation length and electron withdrawing terminal groups play an important role in the light absorption, energy levels and performance of the devices. Among those molecules, devices using a 7-thiophene-unit backbone and a 3-ethylrhodanine (RD) terminal unit produced a 6.1% PCE. With the optimized conjugation length and terminal unit, we borrowed from the results with P-OPV devices to optimize the backbone. Thus we selected BDT (benzo[1,2-b:4,5-b]dithiophene) and DTS (dithienosilole) to replace the central thiophene unit, leading to a PCE of 8.12%. In addition to our molecules, Bazan and co-workers have developed another excellent system using DTS as the core unit that has also achieved a PCE greater than 8%.
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Isotope-coded ATP probe for quantitative affinity profiling of ATP-binding proteins.
Anal. Chem.
PUBLISHED: 07-22-2013
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ATP-binding proteins play significant roles in numerous cellular processes. Here, we introduced a novel isotope-coded ATP-affinity probe (ICAP) as an acylating agent to simultaneously enrich and incorporate isotope label to ATP-binding proteins. By taking advantage of the quantitative capability of this isotope-coded probe, we devised an affinity profiling strategy to comprehensively characterize ATP-protein interactions at the entire proteome scale. False-positive identification of ATP-binding sites derived from nonspecific labeling was effectively minimized through the comparison of the labeling behaviors of lysine residues with the use of low and high concentrations of the ICAP reagents. A total of 258 previously known ATP-binding proteins from lysates of HeLa-S3 and Jurkat-T cells were validated with this affinity profiling assay. Additionally, we demonstrated that this novel quantitative ATP-affinity profiling strategy is particularly useful for unveiling previously unrecognized nucleotide-binding sites in ATP-binding proteins. For example, our profiling results revealed K356 as a new ATP-binding site in HSP90. Furthermore, 293 proteins without documented ATP-binding GO were predicted to be ATP-binding proteins on the basis of our quantitative affinity profiling results. We also uncovered, for the first time, the ATP-binding capability of human proliferating cell nuclear antigen (PCNA), identified the lysine residue involved in ATP binding, and validated the proteins capacity in ATP binding with an independent assay. The ICAP approach described in the present paper should be generally applicable for the quantitative assessment of ATP-binding proteins in proteomic samples from cells and tissues.
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Carbon nanotube - reduced graphene oxide composites for thermal energy harvesting applications.
Adv. Mater. Weinheim
PUBLISHED: 07-17-2013
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By controlling the SWNT-rGO electrode composition and thickness to attain the appropriate porosity and tortuosity, the electroactive surface area is maximized while rapid diffusion of the electrolyte through the electrode is maintained. This leads to an increase in exchange current density between the electrode and electrolyte which results in enhanced thermocell performance.
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Inhibition of hepatocellular carcinoma growth using immunoliposomes for co-delivery of adriamycin and ribonucleotide reductase M2 siRNA.
Biomaterials
PUBLISHED: 06-28-2013
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The chemotherapy combined with gene therapy has received great attention. We developed targeted LPD (liposome-polycation-DNA complex) conjugated with anti-EGFR (epidermal growth factor receptor) Fab co-delivering adriamycin (ADR) and ribonucleotide reductase M2 (RRM2) siRNA (ADR-RRM2-TLPD), to achieve combined therapeutic effects in human hepatocellular carcinoma (HCC) overexpressing EGFR. The antitumor activity and mechanisms of ADR-RRM2-TLPD were investigated. The results showed that RRM2 expression was higher in HCC than in non-HCC tissue, and RRM2 siRNA inhibited HCC cell proliferation, suggesting that RRM2 is a candidate target for HCC therapy. ADR-RRM2-TLPD delivered ADR and RRM2 siRNA to EGFR overexpressing HCC cells specifically and efficiently both in vitro and in vivo, resulting in enhanced therapeutic effects (cytotoxicity, apoptosis and senescence-inducing activity) compared with single-drug loaded or non-targeted controls, including ADR-NC-TLPD (targeted LPD co-delivering ADR and negative control siRNA), RRM2-TLPD (targeted LPD delivering RRM2 siRNA) and ADR-RRM2-NTLPD (non-targeted LPD co-delivering ADR and RRM2 siRNA). Mechanism studies showed that p21 is involved in the combined therapeutic effect of ADR-RRM2-TLPD. The average weight of the orthotopic HCC in mice treated with ADR-RRM2-TLPD was significantly lighter than that of mice treated with other controls. Thus, ADR-RRM2-TLPD represents a potential strategy for combined therapy of HCC overexpressing EGFR.
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A rapid and efficient self-healing thermo-reversible elastomer crosslinked with graphene oxide.
Adv. Mater. Weinheim
PUBLISHED: 06-28-2013
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A self-healing thermo-reversible elastomer is synthesized by cross-linking a hydrogen bonding polymer network with chemically-modified graphene oxide. This nanocomposite allows for both rapid and efficient self-healing (in only several minutes) at room temperature, without the need for any external stimuli (e.g., heating or light exposure), healing agents, plasticizers or solvents.
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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.