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Find video protocols related to scientific articles indexed in Pubmed.
Solvent Effects on the Optical Spectra and Excited-State Decay of triphenylamine-thiadiazole with Hybridized Local Excitation and Intramolecular Charge Transfer.
J Phys Chem A
PUBLISHED: 11-18-2014
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Triphenylamine-thiadiazole molecule (TPA-NZP) is a newly popular highly efficient OLED fluorescent emitter with exciton utilization efficiency exceeding the upper limit of spin statistics (25%). In this work, the optical spectra, and the radiative and non-radiative decay rate constants have been investigated theoretically for TPA-NZP in hexane, ethyl ether, tetrahydrofuran, and dimethyl formamide solvents, in comparison with gas phase. We observed the evolutions of the excited-states from hybridized local and charge transfer (HLCT) character to complete intramolecular charge transfer (CT) character with the increase of the solvent polarities. It is found that upon increasing solvent polarity, the amount of redshift in absorption peak is much less than that of emission, resulting in breakdown of the mirror symmetry. This is because that 0-0 transition energy is red-shifted but the vibration relaxation increases with the solvent polarity, leading to subtraction in absorption while addition in emission. The radiative decay rate constant is calculated to be almost independent on polarity. The non-radiative decay rate increases by almost one order of magnitude from in non-polar hexane to the strongly polarized dimethyl formamide, which are attributed to the dual effects of redshift in gap and enhancement of vibration relaxation by solvent polarity.
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Regioselective Decarboxylative Direct C-H Arylation of Boron Dipyrromethenes (BODIPYs) at 2,6-Positions: A Facile Access to a Diversity-Oriented BODIPY Library.
Org. Lett.
PUBLISHED: 11-18-2014
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A palladium-catalyzed regioselective decarboxylative direct C-H arylation of boron dipyrromethenes (BODIPYs) at the 2,6-positions has been developed as a late-stage approach to rapidly assemble a diversity-oriented BODIPY library. With the complement of this protocol, the direct C-H arylation of BODIPYs becomes regiocontrollable at ?- and ?-positions. A new type of indole-fused BODIPY exhibiting bright red/NIR fluorescence with a large molar extinction coefficient (145?500 M(-1) cm(-1)) and a high quantum yield (71%) has been synthesized for the first time.
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Effect of permafrost properties on gas hydrate petroleum system in the Qilian Mountains, Qinghai, Northwest China.
Environ Sci Process Impacts
PUBLISHED: 11-07-2014
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The gas hydrate petroleum system in the permafrost of the Qilian Mountains, which exists as an epigenetic hydrocarbon reservoir above a deep-seated hydrocarbon reservoir, has been dynamic since the end of the Late Pleistocene because of climate change. The permafrost limits the occurrence of gas hydrate reservoirs by changing the pressure-temperature (P-T) conditions, and it affects the migration of the underlying hydrocarbon gas because of its strong sealing ability. In this study, we reconstructed the permafrost structure of the Qilian Mountains using a combination of methods and measured methane permeability in ice-bearing sediment permafrost. A relationship between the ice saturation of permafrost and methane permeability was established, which permitted the quantitative evaluation of the sealing ability of permafrost with regard to methane migration. The test results showed that when ice saturation is >80%, methane gas can be completely sealed within the permafrost. Based on the permafrost properties and genesis of shallow gas, we suggest that a shallow "gas pool" occurred in the gas hydrate petroleum system in the Qilian Mountains. Its formation was related to a metastable gas hydrate reservoir controlled by the P-T conditions, sealing ability of the permafrost, fault system, and climatic warming. From an energy perspective, the increasing volume of the gas pool means that it will likely become a shallow gas resource available for exploitation; however, for the environment, the gas pool is an underground "time bomb" that is a potential source of greenhouse gas.
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The importance of being capped: terminal capping of an amyloidogenic Peptide affects fibrillation propensity and fibril morphology.
Biochemistry
PUBLISHED: 10-31-2014
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The formation of aggregated fibrillar ?-sheet structures has been proposed to be a generic feature of proteins. Aggregation propensity is highly sequence dependent, and often only part of the protein is incorporated into the fibril core. Therefore, shorter peptide fragments corresponding to the fibril core are attractive fibrillation models. The use of peptide models introduces new termini into the fibrils, yet little attention has been paid to the role these termini may play in fibrillation. Here, we report that terminal modifications of a 10-residue peptide fragment of human islet amyloid polypeptide strongly affect fibrillation kinetics and the resulting fibril morphology. Capping of the N-terminus abolishes fibrillation, while C-terminal capping results in fibrils with a twisted morphology. Peptides with either both termini free or both termini capped form flat fibrils. Molecular dynamics simulations reveal that the N-terminal acetyl cap folds up and interacts with the peptide's hydrophobic side chains, while the uncapped N-terminus in the C-terminally capped version results in twisting of the fibrils due to charge repulsion from the free N-termini. Our results highlight the role of terminal interactions in fibrillation of small peptides and provide molecular insight into the consequences of C-terminal modifications frequently found in peptide hormones in vivo.
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Tomato-Pseudomonas syringae interactions under elevated CO2 concentration: the role of stomata.
J. Exp. Bot.
PUBLISHED: 10-23-2014
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Increasing atmospheric CO2 concentrations ([CO2]) in agricultural and natural ecosystems is known to reduce plant stomatal opening, but it is unclear whether these CO2-induced stomatal alterations are associated with foliar pathogen infections. In this study, tomato plants were grown under ambient and elevated [CO2] and inoculated with Pseudomonas syringae pv. tomato strain DC3000, a strain that is virulent on tomato plants. We found that elevated [CO2] enhanced tomato defence against P. syringae. Scanning electron microscopy analysis revealed that stomatal aperture of elevated [CO2] plants was considerably smaller than their ambient counterparts, which affected the behaviour of P. syringae bacteria on the upper surface of epidermal peels. Pharmacological experiments revealed that nitric oxide (NO) played a role in elevated [CO2]-induced stomatal closure. Silencing key genes involved in NO generation and stomatal closing, nitrate reductase (NR) and guard cell slow-type anion channel 1 (SLAC1), blocked elevated [CO2]-induced stomatal closure and resulted in significant increases in P. syringae infection. However, the SLAC1-silenced plants, but not the NR-silenced plants, still had significantly higher defence under elevated [CO2] compared with plants treated with ambient [CO2]. Similar results were obtained when the stomata-limiting factor for P. syringae entry was excluded by syringe infiltration inoculation. These results indicate that elevated [CO2] induces defence against P. syringae in tomato plants, not only by reducing the stomata-mediated entry of P. syringae but also by invoking a stomata-independent pathway to counteract P. syringae. This information is valuable for designing proper strategies against bacterial pathogens under changing agricultural and natural ecosystems.
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The complete mitochondrial genome of a chronic hepatitis associated liver cancer LEC rat strain.
Mitochondrial DNA
PUBLISHED: 10-21-2014
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Abstract We sequenced a complete mitochondrial genome sequencing of a chronic hepatitis-associated liver cancer disease LEC rat strain for the first time. The total length of the mitogenome was 16,316?bp with 13 protein-coding genes, two ribosomal RNA genes and 22 transfer RNA genes. This mitochondrial genome sequence will provide new genetic resource into liver cancer disease.
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Abiraterone Treatment in Castration-Resistant Prostate Cancer Selects for Progesterone Responsive Mutant Androgen Receptors.
Clin. Cancer Res.
PUBLISHED: 10-17-2014
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Purpose:The CYP17A1 inhibitor abiraterone markedly reduces androgen precursors and is thereby effective in castration-resistant prostate cancer (CRPC). However, abiraterone increases progesterone, which can activate certain mutant androgen receptors (ARs) identified previously in flutamide-resistant tumors. Therefore, we sought to determine if CYP17A1 inhibitor treatment selects for progesterone activated mutant ARs. Experimental Design:AR was examined by targeted sequencing in metastatic tumor biopsies from 18 CRPC patients who were progressing on a CYP17A1 inhibitor (17 on abiraterone, 1 on ketoconazole), alone or in combination with dutasteride, and by whole exome sequencing in residual tumor in one patient treated with neoadjuvant leuprolide plus abiraterone. Results:The progesterone-activated T878A mutant AR was present at high allele frequency in 3 of the 18 CRPC cases. It was also present in one focus of resistant tumor in the neoadjuvant treated patient, but not in a second clonally related resistant focus which instead had lost one copy of PTEN and both copies of CHD1. The T878A mutation appeared to be less common in the subset of CRPC patients treated with abiraterone plus dutasteride, and transfection studies showed that dutasteride was a more potent direct antagonist of the T878A versus the wildtype AR. Conclusions:These findings indicate that selection for tumor cells expressing progesterone-activated mutant ARs is a mechanism of resistance to CYP17A1 inhibition.
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Assessing right ventricular function in patients with hypertrophic cardiomyopathy with cardiac MRI: correlation with the New York Heart Function Assessment (NYHA) classification.
PLoS ONE
PUBLISHED: 09-02-2014
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To determine whether 3.0-T magnetic resonance imaging (MRI) could assess right ventricular (RV) function in patients with hypertrophic cardiomyopathy (HCM), and if this assessment is correlated with the New York Heart Function Assessment (NYHA) classification.
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Carnosine Attenuates Early Brain Injury Through Its Antioxidative and Anti-apoptotic Effects in a Rat Experimental Subarachnoid Hemorrhage Model.
Cell. Mol. Neurobiol.
PUBLISHED: 09-02-2014
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Carnosine (?-alanyl-L-histidine) has been demonstrated to provide antioxidative and anti-apoptotic roles in the animal of ischemic brain injuries and neurodegenerative diseases. The aim of this study was to examine whether carnosine prevents subarachnoid hemorrhage (SAH)-induced early brain injury (EBI) in rats. We found that intraperitoneal administration of carnosine improved neurobehavioral deficits, attenuated brain edema and blood-brain barrier permeability, and decreased reactive oxygen species level at 48 h following SAH in rat models. Carnosine treatment increased tissue copper/zinc superoxide dismutase (CuZn-SOD) and glutathione peroxidase (GSH-Px) enzymatic activities, and reduced post-SAH elevated lactate dehydrogenase (LDH) activity, the concentration of malondialdehyde (MDA), 3-nitrotyrosine (3-NT), 8-hydroxydeoxyguanosine (8-OHDG), interleukin (IL)-1?, IL-6, and tumor necrosis factor-? (TNF-?) in rats. Furthermore, carnosine treatment attenuated SAH-induced microglia activation and cortical neuron apoptosis. These results indicated that administration of carnosine may provide neuroprotection in EBI following SAH in rat models.
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Valley and band structure engineering of folded MoS2 bilayers.
Nat Nanotechnol
PUBLISHED: 08-31-2014
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Artificial structures made of stacked two-dimensional crystals have recently been the focus of intense research activity. As in twisted or stacked graphene layers, these structures can show unusual behaviours and new phenomena. Among the various layered compounds that can be exfoliated, transition-metal dichalcogenides exhibit interesting properties governed by their structural symmetry and interlayer coupling, which are highly susceptible to stacking. Here, we obtain-by folding exfoliated MoS2 monolayers-MoS2 bilayers with different stacking orders, as monitored by second harmonic generation and photoluminescence. Appropriate folding can break the inversion symmetry and suppress interlayer hopping, evoking strong valley and spin polarizations that are not achieved in natural MoS2 bilayers of Bernal stacking. It can also enlarge the indirect bandgap by more than 100?meV through a decrease in the interlayer coupling. Our work provides an effective and versatile means to engineer transition-metal dichalcogenide materials with desirable electronic and optical properties.
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Evaluation of prompted annotation of activity data recorded from a smart phone.
Sensors (Basel)
PUBLISHED: 08-27-2014
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In this paper we discuss the design and evaluation of a mobile based tool to collect activity data on a large scale. The current approach, based on an existing activity recognition module, recognizes class transitions from a set of specific activities (for example walking and running) to the standing still activity. Once this transition is detected the system prompts the user to provide a label for their previous activity. This label, along with the raw sensor data, is then stored locally prior to being uploaded to cloud storage. The system was evaluated by ten users. Three evaluation protocols were used, including a structured, semi-structured and free living protocol. Results indicate that the mobile application could be used to allow the user to provide accurate ground truth labels for their activity data. Similarities of up to 100% where observed when comparing the user prompted labels and those from an observer during structured lab based experiments. Further work will examine data segmentation and personalization issues in order to refine the system.
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Reduced expression of Connexin26 and its DNA promoter hypermethylation in the inner ear of mimetic aging rats induced by d-galactose.
Biochem. Biophys. Res. Commun.
PUBLISHED: 08-23-2014
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Connexin26 (Cx26), one of the major protein subunits forming gap junctions (GJs), is important in maintaining homeostasis in the inner ear and normal hearing. Cx26 mutation is one of the most common causes for inherited nonsyndromic deafness, but the relationship between Cx26 and presbycusis is unknown. Our study aimed at exploring the expression and the aberrant methylation of the promoter region of Cx26 gene in the cochlea of inner ear mimetic aging rats. We applied a mimetic aging of inner ear rat model with mtDNA common deletion by d-gal injection for 8weeks. Real-time RT-PCR and Western blot of rat inner ear tissue indicated that the Cx26 expression decreased in the d-gal group. Further bisulfite sequencing analysis revealed that the methylation status of the promoter region of Cx26 gene in the d-gal group was higher than that in control group. These results indicated that the decrease of Cx26 expression might contribute to the development of presbycusis and the hypermethylation of promoter region of GJB2 might be associated with the Cx26 downregulation.
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Genetically encoded cleavable protein photo-cross-linker.
J. Am. Chem. Soc.
PUBLISHED: 08-13-2014
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We have developed a genetically encoded, selenium-based cleavable photo-cross-linker that allows for the separation of bait and prey proteins after protein photo-cross-linking. We have further demonstrated the efficient capture of the in situ generated selenenic acid on the cleaved prey proteins. Our strategy involves tagging the selenenic acid with an alkyne-containing dimethoxyaniline molecule and subsequently labeling with an azide-bearing fluorophore or biotin probe. This cleavage-and-capture after protein photo-cross-linking strategy allows for the efficient capture of prey proteins that are readily accessible by two-dimensional gel-based proteomics and mass spectrometry analysis.
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Overexpression of Heme Oxygenase 1 Causes Cognitive Decline and Affects Pathways for Tauopathy in Mice.
J. Alzheimers Dis.
PUBLISHED: 08-11-2014
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The stress protein heme oxygenase-1 (HO-1) is upregulated and co-localizes to pathological features, including tauopathies in the brains of individuals with Alzheimer's disease. However, the relationship between HO-1 and Alzheimer's disease remains unclear. In our previous research, the long-term overexpression of HO-1 was shown to promote tau aggregation by inducing tau phosphorylation in the mouse brain. In this study, we found that the long-term overexpression of HO-1 led to cognitive decline in transgenic mice, as determined by the water maze test, and that HO-1 can affect two pathways for tauopathy. Through one pathway, HO-1 promotes the expression of CDK5 by accumulating reactive oxygen species, which are produced by HO-1 downstream products of iron in neuro2a cell lines and mouse brain. Through the second pathway, HO-1 induces tau truncation at D421 in vivo and in vitro. Clearly, there is a HO-1-dependent mechanism responsible for tau protein phosphorylation and tau truncation in vivo and in vitro. Taken together, our results suggest that HO-1 plays an important role in the disease process of tauopathies in AD.
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The effects of genetic variation in FTO rs9939609 on obesity and dietary preferences in Chinese Han children and adolescents.
PLoS ONE
PUBLISHED: 08-11-2014
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The association of the rs9939609 single nucleotide polymorphism in FTO gene with obesity has been extensively investigated in studies of populations of European, African, and Asian ancestry. However, inconsistent results have been reported in Asian populations, and the relationship of FTO variation and dietary behaviors has only rarely been examined in Chinese children and adolescents. The aim of this study was to assess the association of rs9939609 with obesity and dietary preferences in childhood in a Chinese population. Epidemiological data including dietary preferences were collected in interviews using survey questionnaires, and rs9939609 genotype was determined by real-time PCR. The associations of rs9939609 genotypes with obesity and dietary preferences were analyzed by multivariate logistic regression using both additive and dominant models. The results showed that subjects with a TA or AA genotype had an increased risk of obesity compared with the TT participants; the odds ratios (ORs) were 1.47 (95% CI: 1.25-1.71, P?=?1.73×10-6), and 3.32 (95% CI: 2.01-5.47, P?=?2.68×10-6), respectively. After adjusting for age and gender, body mass index, waist circumference, hip circumference, systolic blood pressure, diastolic blood pressure, fasting blood glucose, triglycerides, and low-density lipoprotein cholesterol were higher, and high-density lipoprotein cholesterol was lower in TA and AA participants than in those with the TT genotype. After additionally controlling for body mass index, the association remained significant only for systolic blood pressure (P?=?0.005). Compared with TT participants, those with the AA genotype were more likely to prefer a meat-based diet (OR?=?2.81, 95% CI: 1.52-5.21). The combined OR for obesity in participants with TA/AA genotypes and preference for a meat-based diet was 4.04 (95% CI: 2.8-5.81) compared with the TT participants who preferred a plant-based diet. These findings indicate the genetic variation of rs9939609 is associated with obesity and dietary preferences in Chinese children and adolescents.
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Association between thrombomodulin polymorphisms and coronary artery disease risk: a meta-analysis.
Med. Sci. Monit.
PUBLISHED: 08-10-2014
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The associations between the thrombomodulin (TM) polymorphisms and coronary artery disease (CAD) risk remain controversial. The aim of this study was to evaluate the association of TM polymorphisms with CAD susceptibility using a meta-analysis approach.
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Quantitative biomolecular imaging by dynamic nanomechanical mapping.
Chem Soc Rev
PUBLISHED: 08-08-2014
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The ability to 'see' down to nanoscale has always been one of the most challenging obstacles for researchers to address fundamental questions. For many years, researchers have been developing scanning probe microscopy techniques to improve imaging capability at nanoscale. Among them, atomic force microscopy (AFM) has received considerable attention, which allows probing topography of biological species at real space under physiological environment. Importantly, force measurements in AFM enable researchers to reveal not only the topography but also the relevant physical-chemical properties. AFM-based dynamic nanomechanical mapping (DNM) provides insights into the functions of biological systems by the interpretation of 'force', which are inaccessible by most of the other analytic techniques. This review is aiming to shed light on these recently developed AFM-based DNM techniques for biomolecular imaging, and discuss the relative applications in biological research from the nanomechanical point of view.
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Self-organizing microstructures orientation control in femtosecond laser patterning on silicon surface.
Opt Express
PUBLISHED: 08-05-2014
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Self-organizing rippled microstructures are induced on silicon surface by linearly polarized femtosecond laser pulses. At a near threshold fluence, it is observed that ripple orientation is co-determined by the laser polarization direction and laser scanning parameters (scanning direction and scanning speed) in surface patterning process. Under fixed laser polarization, the ripple orientation can be controlled to rotate by about 40° through changing laser scanning parameters. In addition, it is also observed that the ripple morphology is sensitive to the laser scanning direction, and it is an optimal choice to obtain ordered ripple structures when the angle between laser scanning and laser polarization is less than 45°.
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Functional characterization of a chalcone synthase from the liverwort Plagiochasma appendiculatum.
Plant Cell Rep.
PUBLISHED: 08-04-2014
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A chalcone synthase gene ( PaCHS ) was isolated and functionally characterized from liverwort. The ectopic expression of PaCHS in Marchantia paleacea callus raised the flavonoids content. Chalcone synthase (CHS; EC 2.3.1.74) is pivotal for the biosynthesis of flavonoid and anthocyanin pigments in plants. It produces naringenin chalcone by condensing one p-coumaroyl- and three malonyl-coenzyme A thioesters through a polyketide intermediate that is cyclized by intramolecular Claisen condensation. Although CHSs of higher plants have been extensively studied, enzyme properties of the CHSs in liverworts have been scarcely characterized. In this study, we report the cloning and characterization of CHS (designated as PaCHS) from the liverwort Plagiochasma appendiculatum. The gene product was 60-70 % identical with chalcone synthases from other species, and contained the characteristic conserved Cys-His-Asn catalytic triad. The recombinant PaCHS was able to catalyze p-coumaroyl-CoA and malonyl-CoA to generate naringenin in vitro. Heterologously expressed PaCHS protein showed similar kinetic properties to those of higher plant CHS. The ectopic expression of PaCHS in Marchantia paleacea callus raised the content of the total flavonoids. These results suggested that PaCHS played a key role in the flavonoids biosynthesis in liverworts. Furthermore, when the thallus of P. appendiculatum was treated with abiotic stress inducers methyl jasmonate, salicylic acid and abscisic acid, PaCHS expression was enhanced. This is the first time that a CHS in liverworts has been functionally characterized.
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The Combination of Tet1 with Oct4 Generates High-Quality Mouse Induced Pluripotent Stem Cells (iPSCs).
Stem Cells
PUBLISHED: 08-04-2014
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The DNA dioxygenase Tet1 has recently been proposed to play an important role in the reprogramming of somatic cells to pluripotency. Its oxidization product 5-hydroxymethylcytosine (5hmC), formerly considered an intermediate in the demethylation of 5-methylcytosine (5mC), has recently been implicated as being important in epigenetic reprogramming. Here, we provide evidence that Tet1 (T) can replace multiple transcription factors during somatic cell reprogramming and can generate high-quality mouse induced pluripotent stem cells (iPSCs) with Oct4 (O). The OT-iPSCs can efficiently produce viable mice derived entirely from iPSCs through tetraploid complementation; all 47 adult OT-iPSC mice grew healthily, without tumorigenesis, and had a normal life span. Furthermore, a new secondary reprogramming system was established using the OT all-iPSC mice-derived somatic cells. Our results provide the first evidence that the DNA dioxygenase Tet1 can replace multiple pluripotency transcription factors and can generate high-quality iPSCs with Oct4. Stem Cells 2014.
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Evidence of Stranski-Krastanov growth at the initial stage of atmospheric water condensation.
Nat Commun
PUBLISHED: 07-29-2014
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The precipitation products (rain, snow and so on) of atmospheric water vapour are widely prevalent, and yet the map of its initial stage at a surface is still unclear. Here we investigate the condensation of water vapour occurring in both the hydrophobic-hydrophilic interface (graphene/mica) and the hydrophilic-hydrophilic interface (MoS2/mica) by in situ thermally controlled atomic force microscopy. By monitoring the dynamic dewetting/rewetting transitions process, the ice-like water adlayers, at the hydrophobic-hydrophilic interface and not at the hydrophilic-hydrophilic interface, stacked on top of each other up to three ice-Ih layers (each of height 3.7 ± 0.2 Å), and the transition from layers to droplets was directly visualized experimentally. Compared with molecular dynamics simulation, the Stranski-Krastanov growth model is better suited to describe the whole water condensation process at the hydrophobic-hydrophilic interface. The initial stage of the hydrometeor is rationalized, which potentially can be utilized for understanding the boundary condition for water transport and the aqueous interfacial chemistry.
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Electron-phonon couplings and carrier mobility in graphynes sheet calculated using the Wannier-interpolation approach.
J Chem Phys
PUBLISHED: 07-24-2014
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Electron-phonon couplings and charge transport properties of ?- and ?-graphyne nanosheets were investigated from first-principles calculations by using the density-functional perturbation theory and the Boltzmann transport equation. Wannier function-based interpolation techniques were applied to obtain the ultra-dense electron-phonon coupling matrix elements. Due to the localization feature in Wannier space, the interpolation based on truncated space is found to be accurate. We demonstrated that the intrinsic electron-phonon scatterings in these two-dimensional carbon materials are dominated by low-energy longitudinal-acoustic phonon scatterings over a wide range of temperatures. In contrast, the high-frequency optical phonons play appreciable roles only at high temperature regimes. The electron mobilities of ?- and ?-graphynes are predicted to be ?10(4) cm(2)?V(-1)?s(-1) at room temperature.
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Susceptibility of the rice stem borer, Chilo suppressalis (Lepidoptera: Crambidae), to flubendiamide in China.
J. Econ. Entomol.
PUBLISHED: 07-17-2014
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The rice stem borer, Chilo suppressalis (Walker), is an important rice pest in China, and has evolved resistance to several classes of insecticides. Flubendiamide is a phthalic diamide insecticide that shows selective insecticidal activity against lepidopterous insects. The susceptibility of 40 field populations of C. suppressalis, collected in 2011 and 2012 in seven provinces of south-eastern China, to flubendiamide was determined through rice seedling dipping bioassay method. Of these 40 populations, seven populations that were seldom exposed to flubendiamide were used to set up the baseline sensitivity, and the LC50 value was 0.092 mg/L. Variation in susceptibility among the 40 field populations was high (34-fold). The range of mean lethal concentration (LC50) values in response to this chemical was between 0.032 mg/L (FS11) and 1.090 mg/L (JH12) across the populations. Substantial variations of the susceptibility to flubendiamide were detected among different geographic populations. There was no significant difference observed between years for most populations, except for populations from Jinhua and Lujiang. Resistance ratios to the chemical ranged from 0.8 to 11.8, indicating that most colonies remained susceptible or showed certain decrease in susceptibility. It was found that 16 of the 40 populations had some level of resistance. However, moderate level of resistance was discovered in only one population from JH12 from Zhejiang province (11.8-fold). Other 15 populations showed low level of resistance (5.1-9.3-fold) to flubendiamide. These data are useful in future monitoring programs for detecting any changes in susceptibility as a result of using flubendiamide.
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Fabrication of elliptic microfibers with CO2 laser for high-sensitivity refractive index sensing.
Opt Lett
PUBLISHED: 07-01-2014
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We propose a convenient method for achieving highly birefringent (HiBi) elliptic microfibers by use of the CO2-laser machining and the flame-brushing techniques. With optimization of fabrication process, a high birefringence of up to 2.10×10(-2) is experimentally obtained. Especially, within a polarization Sagnac interferometer acting as a refractive index (RI) sensor, both positive and abnormal negative sensitivity is measured, dependent on the geometrical variables of the HiBi microfiber. The maximum RI sensitivity is ?195,348??nm/RI-unit around RI=1.35887, which is the highest among the microfiber devices as reported, to our knowledge.
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A novel strategy for preparing glycopeptide molecular probe using fluorous technology.
Protein Pept. Lett.
PUBLISHED: 07-01-2014
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A novel and convenient strategy for iodine labeled glycopeptide molecular probe and purification was developed. The fluorine rich bi-functional coupling agent, 4-tris(2-perfluorohexylethyl)stannylbenzoate succinimidyl ester, was successfully synthesized via 5 steps starting from the fluorous Grignard reagent. It was purified by a simple and fast isolation using perfluorinated hexanes (FC-72). The "cold" iodine labeled yield for the coupling agent was as high as 92% within 15 min. The iodine-labeled product was only in organic fractions as we expected. It was shown that there was only one major peak in organic fractions according to HPLC. Finally, the iodine-labeled coupling agent was applied to label glycopeptide and afforded a high yield of 87% within 30 min.
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Complete mitochondrial genome of the giant African snail, Achatina fulica (Mollusca: Achatinidae): a novel location of putative control regions (CR) in the mitogenome within Pulmonate species.
Mitochondrial DNA
PUBLISHED: 07-01-2014
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Abstract The whole sequence (15,057?bp) of the mitochondrial DNA (mtDNA) of the terrestrial snail Achatina fulica (order Stylommatophora) was determined. The mitogenome, as the typical metazoan mtDNA, contains 13 protein-coding genes (PCG), 2 ribosomal RNA genes (rRNA) and 22 transfer RNA genes (tRNA). The tRNA genes include two trnS without standard secondary structure. Interestingly, among the known mitogenomes of Pulmonata species, we firstly characterized an unassigned lengthy sequence (551?bp) between the cox1 and the trnV which may be the CR for the sake of its AT bases usage bias (65.70%) and potential hairpin structure.
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Hydrated human corneal stroma revealed by quantitative dynamic atomic force microscopy at nanoscale.
ACS Nano
PUBLISHED: 06-30-2014
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The structures and mechanical properties of human tissues are significantly influenced by water. The functionality of the human cornea can be linked to the hydrated collagen fibers. By applying quantitative dynamic atomic force microscopy to investigate morphological and mechanical property variations of corneal stroma under different hydration levels, we found that the collagen fibers in the stromal tissue show the specific periodicities and the stiffness of giga-Pa magnitude at 40% humidity. However, under increasing hydration, the collagen fibers clearly show nanoparticle structures along the fibers with the stiffness in mega-Pa magnitude. By increasing the hydration time, the stroma regains the fiber structure but with larger diameter. The age-dependency in stiffness was further investigated. The interplay of structures and nanomechanical mapping may be applied for the future diagnosis and assessment or even pathologic analysis.
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Aggregation effects on the optical emission of 1,1,2,3,4,5-hexaphenylsilole (HPS): a QM/MM study.
J Phys Chem A
PUBLISHED: 06-23-2014
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We investigate the photophysical property for 1,1,2,3,4,5-hexaphenylsilole (HPS) through combined quantum mechanical and molecular mechanical (QM/MM) simulations. Under the displaced harmonic oscillator approximation with consideration of the Duschinsky rotation effect (DRE), the radiative and nonradiative rates of the excited-state decay processes for HPS are calculated by using the analytical vibration correlation function approach coupled with first-principles calculations. The intermolecular packing effect is incorporated through electrostatic interaction modeled by a force field. We find that from the gas phase to the solid state (i) the side phenyl ring at the 5-position becomes coplanar with the central silacycle, which increases the degree of conjugation, thus accelerating the radiative decay process, and (ii) the rotation of the side phenyl ring at the 2-position is restricted, which blocks the excited-state nonradiative decay channels. Such a synergetic effect largely enhances the solid-state luminescence quantum efficiency through reducing the nonradiative decay rate by about 4 orders of magnitude, leading to the radiative decay overwhelming the nonradiatvie decay. In addition, the calculated solid-phase absorption and emission optical spectra of HPS are found to be in agreement with the experiment.
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Causes of death among persons who survive an acute ischemic stroke.
Curr Neurol Neurosci Rep
PUBLISHED: 06-22-2014
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Stroke and especially its complications are a leading cause of death. Despite reduced morbidity in some developed countries, mortality in stroke patients is still high worldwide. In the past decades, treatment of acute stroke has focused on early intervention, such as revascularization and cerebral edema prevention. However, long-term clinical observations indicate that poststroke pneumonia, cardiovascular complications, and vascular embolism are the major reasons for the increased death rate after stroke. Few evidence-based data are available currently to guide the management of these complications. Thus, systematic studies of these adverse events are essential and urgent to improve survival after stroke.
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Complete mitochondrial genome of the pelagic stingray Pteroplatytrygon violacea (Myliobatiformes: Dasyatidae).
Mitochondrial DNA
PUBLISHED: 06-19-2014
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Abstract The pelagic stingray Pteroplatytrygon violacea is the only pelagic species of the Dasyatidae (Chondrichthyes: Elasmobranchii), which is widely distributed in all tropical, subtropical and temperate oceans. In this study, the complete mitochondrial genome of Pteroplatytrygon violacea was determined. It is 17,665?bp in length and contains 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and 1 control region, with the typical gene order and direction of transcription of vertebrates. The overall nucleotide compositions of the whole mitogenome are 30.8% A, 26.9% C, 28.6% T and 13.7% G. The ND2 and CO1 sequences are highly similar to the corresponding sequences of this species available in NCBI collected from the Atlantic sea.
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Galeterone prevents androgen receptor binding to chromatin and enhances degradation of mutant androgen receptor.
Clin. Cancer Res.
PUBLISHED: 05-29-2014
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Galeterone inhibits the enzyme CYP17A1 and is currently in phase II clinical trials for castration-resistant prostate cancer (CRPC). Galeterone is also a direct androgen receptor (AR) antagonist and may enhance AR degradation. This study was undertaken to determine the molecular basis for AR effects and their therapeutic potential.
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Complete mitochondrial genome of Aphis gossypii Glover (Hemiptera: Aphididae).
Mitochondrial DNA
PUBLISHED: 05-29-2014
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Abstract The complete mitochondrial genome of the cotton-melon aphid, Aphis gossypii Glover, was sequenced using a combination of high-throughput sequencing, traditional PCR amplification, and Sanger sequencing. The genome is 15,869?bp in length, and contains 37 typical coding genes, one non-coding AT-rich region, and a repeat region found exclusively in aphids. The base composition of the genome is A (45.4%), T (38.3%), C (10.4%), and G (5.9%). All protein coding genes start with a typical ATN initiation codon; all genes use the standard termination codon (TAA) except ND4 that ends with a single TA.
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Maize growing duration was prolonged across China in the past three decades under the combined effects of temperature, agronomic management, and cultivar shift.
Glob Chang Biol
PUBLISHED: 05-28-2014
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Maize phenology observations at 112 national agro-meteorological experiment stations across China spanning the years 1981-2009 were used to investigate the spatiotemporal changes of maize phenology, as well as the relations to temperature change and cultivar shift. The greater scope of the dataset allows us to estimate the effects of temperature change and cultivar shift on maize phenology more precisely. We found that maize sowing date advanced significantly at 26.0% of stations mainly for spring maize in northwestern, southwestern and northeastern China, although delayed significantly at 8.0% of stations mainly in northeastern China and the North China Plain (NCP). Maize maturity date delayed significantly at 36.6% of stations mainly in the northeastern China and the NCP. As a result, duration of maize whole growing period (GPw) was prolonged significantly at 41.1% of stations, although mean temperature (Tmean) during GPw increased at 72.3% of stations, significantly at 19.6% of stations, and Tmean was negatively correlated with the duration of GPw at 92.9% of stations and significantly at 42.9% of stations. Once disentangling the effects of temperature change and cultivar shift with an approach based on accumulated thermal development unit, we found that increase in temperature advanced heading date and maturity date and reduced the duration of GPw at 81.3%, 82.1% and 83.9% of stations on average by 3.2, 6.0 and 3.5 days/decade, respectively. By contrast, cultivar shift delayed heading date and maturity date and prolonged the duration of GPw at 75.0%, 94.6% and 92.9% of stations on average by 1.5, 6.5 and 6.5 days/decade, respectively. Our results suggest that maize production is adapting to ongoing climate change by shift of sowing date and adoption of cultivars with longer growing period. The spatiotemporal changes of maize phenology presented here can further guide the development of adaptation options for maize production in near future.
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Xist repression shows time-dependent effects on the reprogramming of female somatic cells to induced pluripotent stem cells.
Stem Cells
PUBLISHED: 05-17-2014
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Although the reactivation of silenced X chromosomes has been observed as part of the process of reprogramming female somatic cells into induced pluripotent stem cells (iPSCs), it remains unknown whether repression of the X-inactive specific transcript (Xist) can greatly enhance female iPSC induction similar to that observed in somatic cell nuclear transfer studies. In this study, we discovered that the repression of Xist plays opposite roles in the early and late phases of female iPSCs induction. Our results demonstrate that the downregulation of Xist by an isopropyl ?-d-1-thiogalactopyranoside (IPTG)-inducible short hairpin RNA (shRNA) system can greatly impair the mesenchymal-to-epithelial transition (MET) in the early phase of iPSC induction but can significantly promote the transition of pre-iPSCs to iPSCs in the late phase. Furthermore, we demonstrate that although the knockdown of Xist did not affect the H3K27me3 modification on the X chromosome, macroH2A was released from the inactivated X chromosome (Xi). This enables the X chromosome silencing to be a reversible event. Moreover, we demonstrate that the supplementation of vitamin C (Vc) can augment and stabilize the reversible X chromosome by preventing the relocalization of macroH2A to the Xi. Therefore, our study reveals an opposite role of Xist repression in the early and late stages of reprogramming female somatic cells to pluripotency and demonstrates that the release of macroH2A by Xist repression enables the transition from pre-iPSCs to iPSCs.
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[Phenology of forest vegetation in northeast of China in ten years using remote sensing].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 05-15-2014
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Plant phenology is the best indicator of terrestrial ecosystem response to climate change and it becomes a hot issue in the study of global change. The forest in northeast of China plays an important part in global forest ecosystem. In this paper, yearly integrated Normalized Difference Vegetation Index (NDVI) of forest vegetation in northeast China was calculated based on Spot Vegetation datasets from 2001-2010, which has been filtered using Savtiky-Galoy method. And then, the yearly integrated NDVI profile was fitted using a logistic model. Two key parameters of forest phenology (start of season, SOS; end of season, EOS) were extracted according to the greatest rate of curvature of fitted cumulative NDVI and the length of forest phenology (length of season, LOS) was also analyzed. The main conclusions of this paper are (1) SOS mainly occurs in the 110th-140th day and EOS in 260th and 290th day. SOS displays a marked delayed from south to north while EOS gradually advances. However, the changes of SOS and EOS in ten years are not obvious. (2) Corresponding to the SOS and EOS, LOS of forest in study area mainly occurs in the 120th-160th day; however, it is spatially heterogeneous. LOS of forest in Greater Khingan Mountains is shorter (about 120-140 day) than forests in Xiao Hinggan Ling and Changbai Mountains (about 160 day). The results in this paper are concordant with records of phenology in situ measurements and previous researches in the same area. It indicates that forest phenophases using method in this paper from Spot Vegetation dataset is feasible.
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Primary dedifferentiated liposarcoma of the femur presenting with malignant fibrous histiocytoma: A case report and review of the literature.
Oncol Lett
PUBLISHED: 04-16-2014
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In the current report a case of a 26-year-old male with a primary dedifferentiated liposarcoma of the femur accompanied by malignant fibrous histiocytoma is presented. The patient complained of a dull intermittent pain, for three months, along the anterolateral aspect of the right knee and was referred to Southwest Hospital (Chongqing, China) in May 2013. All of the radiographic findings, including radiography, magnetic resonance image and emission computed tomography (CT) supported the diagnosis of a primary malignant bone tumor. CT-guided biopsy results demonstrated blood clots and a small quantity of heterogeneous cells. Thus, a limb-salvage procedure, involving a wide resection and total knee endoprosthesis replacement, was performed in May 2012. The final pathological diagnosis was of a primary dedifferentiated liposarcoma of the femur and the dedifferentiated tissue was identified as malignant fibrous histiocytoma. On review of the literature, it was identified that primary intraosseous liposarcoma are a rare and malignant tumor of the skeletal system, with only a small number of cases reported in the English literature since 1980. To the best of our knowledge, a case of dedifferentiated liposarcoma has not previously been reported.
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Optical and application study of gas-liquid discharge excited by bipolar nanosecond pulse in atmospheric air.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 04-12-2014
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In this study, a bipolar nanosecond pulse with 20ns rising time is employed to generate air gas-liquid diffuse discharge plasma with room gas temperature in quartz tube at atmospheric pressure. The image of the discharge and optical emission spectra of active species in the plasma are recorded. The plasma gas temperature is determined to be approximately 390K by compared the experimental spectra with the simulated spectra, which is slightly higher than the room temperature. The result indicated that the gas temperature rises gradually with pulse peak voltage increasing, while decreases slightly with the electrode gap distance increasing. As an important application, bipolar nanosecond pulse discharge is used to sterilize the common microorganisms (Actinomycetes, Candida albicans and Escherichia coli) existing in drinking water, which performs high sterilization efficiency.
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Melanoma differentiation-associated gene-7/interleukin-24 as a potential prognostic biomarker and second primary malignancy indicator in head and neck squamous cell carcinoma patients.
Tumour Biol.
PUBLISHED: 04-10-2014
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The significance of melanoma differentiation-associated gene-7/interleukin-24 (MDA-7/IL-24) expression in head and neck squamous cell carcinoma (HNSCC) remains unclear. This study was designed to investigate and evaluate the clinical significance of MDA-7/IL-24 expression in HNSCC by detecting expression by immunostaining in 131 HNSCC specimens. The function of MDA-7/IL-24 was investigated by real-time polymerase chain reaction (PCR) and Western blot in Ad5.mda-7-infected HNSCC cell lines. Our results showed that MDA-7/IL-24 was mainly expressed in the cytoplasm of HNSCC cells. MDA-7/IL-24 high patients presented with a favorable postoperative prognosis compared with MDA-7/IL-24 low patients, and high expression of MDA-7/IL-24 was significantly correlated with a lower incidence of second primary malignancies (SPMs) in the head and neck regions. In vitro assays showed that high expression of MDA-7/IL-24 could upregulate the expression of the epithelial terminal differentiation markers cytokeratin (KRT) 1, KRT4, KRT13, phosphorylated endoplasmic reticulum stress protein (p)-EIF2a, and the apoptosis-related protein cleaved caspase-3. It also downregulated the epithelial proliferative markers KRT5, KRT14, Integrin ?4, and anti-apoptosis protein Bcl-2, which might be partially involved in the underlying mechanisms of Ad.mda-7-mediated HNSCC differentiation and apoptosis. Our results indicate that MDA-7/IL-24 can be a prognostic biomarker and an indicator of second primary malignancies (SPM) in HNSCC.
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Intercalation of dodecylamine into kaolinite and its layering structure investigated by molecular dynamics simulation.
J Colloid Interface Sci
PUBLISHED: 04-08-2014
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Dodecylamine was successfully intercalated into the layer space of kaolinite by utilizing the methanol treated kaolinite-dimethyl sulfoxide (DMSO) intercalation complex as an intermediate. The basal spacing of kaolinite, measured by X-ray diffraction (XRD), increased from 0.72 nm to 4.29 nm after the intercalation of dodecylamine. Also, the significant variation observed in the Fourier Transform Infrared Spectroscopy (FTIR) spectra of kaolinite when intercalated with dodecylamine verified the feasibility of intercalation of dodecylamine into kaolinite. Isothermal-isobaric (NPT) molecular dynamics simulation with the use of Dreiding force field was performed to probe into the layering behavior and structure of nanoconfined dodecylamine in the kaolinite gallery. The concentration profiles of the nitrogen atom, methyl group and methylene group of intercalated dodecylamine molecules in the direction perpendicular to the kaolinite basal surface indicated that the alkyl chains within the interlayer space of kaolinite exhibited an obvious layering structure. However, the unified bilayer, pseudo-trilayer, or paraffin-type arrangements of alkyl chains deduced based on their chain length combined with the measured basal spacing of organoclays were not found in this study. The alkyl chains aggregated to a mixture of ordered paraffin-type-like structure and disordered gauche conformation in the middle interlayer space of kaolinite, and some alkyl chains arranged in two bilayer structures, in which one was close to the silica tetrahedron surface, and the other was close to the alumina octahedron surface with their alkyl chains parallel to the kaolinite basal surface.
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Computational evaluation of optoelectronic properties for organic/carbon materials.
Acc. Chem. Res.
PUBLISHED: 04-04-2014
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Conspectus Organic optoelectronic materials are used in a variety of devices, including light-emitting diodes, field-effect transistors, photovoltaics, thermoelectrics, spintronics, and chemico- and biosensors. The processes that determine the intrinsic optoelectronic properties occur either in the photoexcited states or within the electron-pumped charged species, and computations that predict these optical and electrical properties would help researchers design new materials. In this Account, we describe recent advances in related density functional theory (DFT) methods and present case studies that examine the efficiency of light emission, carrier mobility, and thermoelectric figures of merit by calculation of the electron-vibration couplings. First we present a unified vibrational correlation function formalism to evaluate the excited-state radiative decay rate constant kr, the nonradiative decay rate constant knr, the intersystem crossing rate constant kISC, and the optical spectra. The molecular parameters that appear in the formalism, such as the electronic excited-state energy, vibrational modes, and vibronic couplings, require extensive DFT calculations. We used experiments for anthracene at both low and ambient temperatures to benchmark the calculated photophysical parameters. In the framework of Fermi's golden rule, we incorporated the non-adiabatic coupling and the spin-orbit coupling to evaluate the phosphorescence efficiency and emission spectrum. Both of these are in good agreement with experimental results for anthracene and iridium compounds. Band electron scattering and relaxation processes within Boltzmann theory can describe charge transport in two-dimensional carbon materials and closely packed organic solids. For simplicity, we considered only the acoustic phonon scattering as modeled by the deformation potential approximation coupled with extensive DFT calculations for band structures. We then related the carrier mobility to the band-edge shift associated with the lattice dilation of longitudinal waves. The calculated relaxation time was in good agreement with experimental data for the graphene sheet, which supports the methodology. We then found that the intrinsic electron mobility for a 6,6,12-graphyne sheet can be even larger than that of graphene. We extended this approach to investigate the thermoelectric transport of electrons in metal phthalocyanines, which showed reasonable Seebeck coefficients when compared with experiments. For the thermal lattice transport, we employed nonequilibrium molecular dynamics simulations. Combining both electron transport and lattice thermal conductivity, we can evaluate the thermoelectric figure of merit.
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Mitochondria autophagy is induced after hypoxic/ischemic stress in a Drp1 dependent manner: the role of inhibition of Drp1 in ischemic brain damage.
Neuropharmacology
PUBLISHED: 03-31-2014
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Mitochondria dysfunction is implicated in diverse conditions, including metabolic and neurodegenerative disorders. Mitochondrial dynamics has attracted increasing attention as to its relationship with mitochondria autophagy, also known as mitophagy, which is critical for degradation of dysfunctional mitochondria maintaining mitochondrial homeostasis. Mitochondrial ?ssion and its role in clearance of injured mitochondria in acute ischemic injury, however, have not been elucidated yet. Here we showed that hypoxic/ischemic conditions led to fragmentation of mitochondria and induction of mitophagy in permanent middle cerebral artery occlusion (pMCAO) rats and oxygen-glucose deprivation (OGD) PC12 cells. Inhibition of Drp1 by pharmacologic inhibitor or siRNA resulted in accumulation of damaged mitochondria mainly through selectively blocking mitophagy without affecting mitochondrial biogenesis and non-selective autophagy. Drp1 inhibitors increased the infarct volume and aggravated the neurological de?cits in a rat model of pMCAO. We demonstrated that the devastating role of disturbed mitochondrial fission by inhibiting Drp1 contributed to the damaged mitochondria-mediated injury such as ROS generation, cyt-c release and activation of caspase-3. Taken together, we proved that under hypoxic/ischemic stress a Drp1-dependent mitophagy was triggered which was involved in the removal of damaged mitochondria and cellular survival at the early stage of hypoxic/ischemic injury. Thus, Drp1 related pathway involved in selective removal of dysfunctional mitochondria is proposed as an efficient target for treatment of cerebral ischemia.
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Methylated cysteine dioxygenase-1 gene promoter in the serum is a potential biomarker for hepatitis B virus-related hepatocellular carcinoma.
Tohoku J. Exp. Med.
PUBLISHED: 03-21-2014
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Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related mortality worldwide. Epigenetic analysis has attracted increasing attention in the molecular diagnosis of HCC. Cysteine dioxygenase 1 (CDO1) is a key enzyme in the taurine biosynthetic pathway and converts cysteine to cysteine sulfinate. The CDO1 gene is a tumor suppressor gene and is usually silenced by the methylation of its promoter in carcinogenesis. In this study, we evaluated whether the methylation status of CDO1 gene promoter is of diagnostic value for hepatitis B virus (HBV)-related HCC. The CDO1 promoter methylation status was determined in serum samples using methylation-specific polymerase chain reaction (MSP) in a cohort of 123 patients with HBV-related HCC, 28 with liver cirrhosis (LC), 29 with chronic hepatitis B (CHB) and 20 healthy controls. The frequency of the CDO1 promoter methylation in HBV-related HCC (42.3%) was significantly higher than that in LC (14.3%), CHB (6.9%) and healthy controls (0%) (P = 0.006; P < 0.0001; P < 0.0001; respectively). Furthermore, in HCC patients, the frequency of CDO1 promoter methylation was higher in advanced stages (III-IV) (53%) than the early stages (I-II) (20%) (P = 0.001). Evaluation of the CDO1 promoter methylation status in serum, in combination with AFP (> 20 ng/ml), significantly improved the diagnostic value, with sensitivity and specificity of 82.9% and 75.4%, respectively in distinguishing HCC from LC and CHB. In conclusion, methylation status of serum CDO1 gene promoter may be helpful in the diagnosis of HCC and the estimation of the HCC stages.
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Waist-to-Height Ratio: a simple, effective and practical screening tool for childhood obesity and metabolic syndrome.
Prev Med
PUBLISHED: 03-18-2014
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This study aimed to evaluate the diagnostic value of Waist-to-Height Ratio in early detection of obesity and metabolic syndrome in Chinese children and adolescents.
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A bionic camera-based polarization navigation sensor.
Sensors (Basel)
PUBLISHED: 03-10-2014
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Navigation and positioning technology is closely related to our routine life activities, from travel to aerospace. Recently it has been found that Cataglyphis (a kind of desert ant) is able to detect the polarization direction of skylight and navigate according to this information. This paper presents a real-time bionic camera-based polarization navigation sensor. This sensor has two work modes: one is a single-point measurement mode and the other is a multi-point measurement mode. An indoor calibration experiment of the sensor has been done under a beam of standard polarized light. The experiment results show that after noise reduction the accuracy of the sensor can reach up to 0.3256°. It is also compared with GPS and INS (Inertial Navigation System) in the single-point measurement mode through an outdoor experiment. Through time compensation and location compensation, the sensor can be a useful alternative to GPS and INS. In addition, the sensor also can measure the polarization distribution pattern when it works in multi-point measurement mode.
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A combination of extended fuzzy AHP and fuzzy GRA for government E-tendering in hybrid fuzzy environment.
ScientificWorldJournal
PUBLISHED: 03-07-2014
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The recent government tendering process being conducted in an electronic way is becoming an inevitable affair for numerous governmental agencies to further exploit the superiorities of conventional tendering. Thus, developing an effective web-based bid evaluation methodology so as to realize an efficient and effective government E-tendering (GeT) system is imperative. This paper firstly investigates the potentiality of employing fuzzy analytic hierarchy process (AHP) along with fuzzy gray relational analysis (GRA) for optimal selection of candidate tenderers in GeT process with consideration of a hybrid fuzzy environment with incomplete weight information. We proposed a novel hybrid fuzzy AHP-GRA (HFAHP-GRA) method that combines an extended fuzzy AHP with a modified fuzzy GRA. The extended fuzzy AHP which combines typical AHP with interval AHP is proposed to obtain the exact weight information, and the modified fuzzy GRA is applied to aggregate different types of evaluation information so as to identify the optimal candidate tenderers. Finally, a prototype system is built and validated with an illustrative example for GeT to confirm the feasibility of our approach.
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Mucosal and systemic immunization with a novel attenuated pneumococcal vaccine candidate confer serotype independent protection against Streptococcus pneumoniae in mice.
Vaccine
PUBLISHED: 03-06-2014
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Despite the availability of effective vaccines, Streptococcus pneumoniae is still one of the major infectious diseases causing substantial morbidity and mortality in children under 5 years old. In this study, we demonstrate the protective efficacy of S. pneumoniae SPY1, a novel live attenuated vaccine strain against pneumococcal infection in murine models. This strain was characterized by defects in three important pneumococcal virulence factors including capsule, teichoic acids and pneumolysin. The lactate dehydrogenase assays and in vivo animal experiments demonstrated a significantly attenuated virulence and a reduced nasopharyngeal colonization for the SPY1 strain. We also show that mucosal and systemic immunization with the live SPY1 strain induced protective immune responses against pneumococci. Mucosal immunization with SPY1 offered better protection against colonization challenge with strains TIGR4 and serotype 19F than systemic SPY1 immunization. In invasive infection models, mucosal vaccination with the SPY1 strain conferred complete protection against D39 and clinical serotype 6B and 3 strains. Notably, intranasal vaccination with the SPY1 strain conferred superior protection against pneumococcal invasive disease compared with the commercial available vaccines. SPY1 strain was shown to elicit high levels of serotype-independent antibodies and a mixed cellular immune response. Besides, the SPY1 serum was able to passively protect mice against invasive challenge with D39 strain, indicating the protective effect of the antibody-mediated responses. Together, the SPY1 strain may be a promising live vaccine strain to protect pneumococcal infection.
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Functional characterization of a Plagiochasma appendiculatum flavone synthase I showing flavanone 2-hydroxylase activity.
FEBS Lett.
PUBLISHED: 03-05-2014
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FNS I is a 2-oxoglutarate dependent dioxygenase (2-ODD) found mainly in species of the Apiaceae family. Here, an FNS I cDNA sequence was isolated from the liverwort Plagiochasma appendiculatum (Aytoniaceae) and characterized. The recombinant protein exhibited high FNS I activity catalyzing the conversion of naringenin to apigenin and 2-hydroxynaringenin. The critical residue for flavanone-2-hydroxylation activity was Tyr240, as identified from homology modeling and site-directed mutagenesis. The recombinant protein also showed some flavonol synthase activity, as it can convert dihydrokaempferol to kaempferol. When the Leu311 residue was mutated to Phe, the enzyme's capacity to convert dihydrokaempferol to kaempferol was substantially increased. PaFNS I represents a 2-ODD in which a hydrophobic ?-stacking interaction between the key residue and the naringenin A-ring determines 2-hydroxyflavanone formation.
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Gold-catalyzed C(sp3)-H/C(sp)H coupling/cyclization/oxidative alkynylation sequence: a powerful strategy for the synthesis of 3-alkynyl polysubstituted furans.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 02-15-2014
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In sharp contrast to the gold-catalyzed reactions of alkynes/allenes with nucleophiles, gold-catalyzed oxidative cross-couplings and especially C-H/C-H cross-coupling have been under represented. By taking advantage of the unique redox property and carbophilic ??acidity of gold, this work realizes the first gold-catalyzed direct C(sp(3))-H alkynylation of 1,3-dicarbonyl compounds with terminal alkynes under mild reaction conditions, with subsequent cyclization and in situ oxidative alkynylation. A variety of terminal alkynes including aryl, heteroaryl, alkenyl, alkynyl, alkyl, and cyclopropyl alkynes all successfully participate in the domino reaction. The protocol offers a simple and region-defined approach to 3-alkynyl polysubstituted furans.
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Prognoses of patients with acute-on-chronic hepatitis B liver failure are closely associated with altered SOCS1 mRNA expression and cytokine production following glucocorticoid treatment.
Cell. Mol. Immunol.
PUBLISHED: 02-13-2014
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Suppressor of cytokine signaling (SOCS) 1 plays a crucial role in the immune response and might contribute to the prognoses of liver failure treated with glucocorticoid. We recruited 47 acute-on-chronic hepatitis B liver failure (ACHBLF) patients receiving glucocorticoid treatment and 30 healthy controls to determine the potential effects of glucocorticoid on the transcriptional level of SOCS1 in peripheral blood mononuclear cells. On the third and twenty-eighth days of glucocorticoid treatment, SOCS1 expression was negatively correlated with model for end-stage liver disease (MELD) score. Interleukin-6 (IL-6) and tumor-necrosis factor-? (TNF-?) levels were statistically lower, while the SOCS1 transcription level was higher in survivors than non-survivors both in pre- and post-treatment ACHBLF patients. The methylation rate of the SOCS1 promoter in ACHBLF patients was higher than in healthy control patients as determined by methylation-specific polymerase chain reaction. The mRNA level of SOCS1 in methylated promoters was significantly lower than from patients with unmethylated SOCS1 promoters. interferon (IFN)-?-responsive and STAT1-dependent gene expression was higher in survivors and was dramatically decreased with rising expression of SOCS1 after glucocorticoid treatment. Mortality rates were significantly higher in methylated patients than for those without methylation at the end of a 90-day follow-up. Furthermore, we found that five in six surviving patients displayed demethylated SOCS1 on the twenty-eighth day after treatment, while that number was 3 in 10 in the non-survivors. These findings suggested that ACHBLF patients without SOCS1 methylation may have a favorable response to corticosteroid treatment.
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MiR-145 regulates cancer stem-like properties and epithelial-to-mesenchymal transition in lung adenocarcinoma-initiating cells.
Tumour Biol.
PUBLISHED: 02-07-2014
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MicroRNA-145 (MiR-145) is an important regulator of tumorigenesis. Our previous work indicated that miR-145 reduced the proliferation and invasion as well as the tumorosphere growth capacity in lung adenocarcinoma cells. However, the underlying molecular mechanisms remain elusive. Here, we reported that the expression level of miR-145 was downregulated in lung adenocarcinoma tissues and negatively correlated with the expression level of Oct4. MiR-145 inhibited the proliferation of lung cancer-initiating cells (LCICs), partially by regulating Oct4 expression. Furthermore, we found that miR-145 exerted repressive effect on cancer stem cell properties and inhibited epithelial-mesenchymal transition (EMT) in vitro, also partially by regulating Oct4. Finally, we confirmed the repressive effect of miR-145 on cancer stem cell properties and EMT in vivo. Taken together, these evidences suggest that miR-145 serves as a tumor suppressor which downregulates LCICs' cancer stem cell properties and EMT process by targeting Oct4, leading to the inhibition of tumor growth and metastasis.
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Aggregation induced blue-shifted emission--the molecular picture from a QM/MM study.
Phys Chem Chem Phys
PUBLISHED: 02-07-2014
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In general, optical emission in the solid-state is red-shifted with respect to the solution phase. A series of recently synthesized compounds exhibits aggregation induced blue-shifted emission (AIBSE) phenomena. By employing a polarizable continuum model (PCM) and a hybrid quantum mechanics/molecular mechanics (QM/MM) approach, we investigate the excited-state electronic structures of some typical AIE-active molecules both in solvents and in aggregates at the time-dependent density functional theory (TD-DFT) level. It is found that the AIBSE phenomena originate from the smaller reorganization energy in aggregates than in the solution phase, as evidenced through the restricted structural relaxation, planarization in the excited state, and freezing of low-frequency out-of-plane twists in the transition state.
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Modulating a?33-42 peptide assembly by graphene oxide.
Chemistry
PUBLISHED: 02-03-2014
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Graphene oxide (GO) is utilized as the modulator to tune the formation and development of amyloid fibrils (A?33-42 ). Atomic force microscopy temporal evolution measurements reveal that the initial binding between the peptide monomer and the large available surface of the GO sheets can redirect the assembly pathway of amyloid beta. The results support the possibility to develop graphene-based materials to inhibit amyloidosis.
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MT1M and MT1G promoter methylation as biomarkers for hepatocellular carcinoma.
World J. Gastroenterol.
PUBLISHED: 01-10-2014
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To investigate the potential of promoter methylation of two tumor suppressor genes (TSGs) as biomarkers for hepatocellular carcinoma (HCC).
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From charge transport parameters to charge mobility in organic semiconductors through multiscale simulation.
Chem Soc Rev
PUBLISHED: 01-06-2014
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This review introduces the development and application of a multiscale approach to assess the charge mobility for organic semiconductors, which combines quantum chemistry, Kinetic Monte Carlo (KMC), and molecular dynamics (MD) simulations. This approach is especially applicable in describing a large class of organic semiconductors with intermolecular electronic coupling (V) much less than intramolecular charge reorganization energy (?), a situation where the band description fails obviously. The charge transport is modeled as successive charge hopping from one molecule to another. We highlight the quantum nuclear tunneling effect in the charge transfer, beyond the semiclassical Marcus theory. Such an effect is essential for interpreting the "paradoxical" experimental finding that optical measurement indicated "local charge" while electrical measurement indicated "bandlike". Coupled MD and KMC simulations demonstrated that the dynamic disorder caused by intermolecular vibration has negligible effect on the carrier mobility. We further apply the approach for molecular design of n-type materials and for rationalization of experimental results. The charge reorganization energy is analyzed through decomposition into internal coordinates relaxation, so that chemical structure contributions to the intramolecular electron-phonon interaction are revealed and give helpful indication to reduce the charge reorganization energy.
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Charge-transfer complex crystal based on extended-?-conjugated acceptor and sulfur-bridged annulene: charge-transfer interaction and remarkable high ambipolar transport characteristics.
Adv. Mater. Weinheim
PUBLISHED: 01-05-2014
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A single crystal of a novel mixed-stack donor-acceptor complex formed by a tetracyanoquinodimethane derivative with an extended ?-conjugated system and a sulfur-bridged annulene displays the highest ambipolar transport behavior among donor-acceptor complexes reported with electron and hole mobilities reaching up to 0.24 and 0.77 cm(2) V(-1) s(-1) , respectively.
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High-throughput sequencing reveals the disruption of methylation of imprinted gene in induced pluripotent stem cells.
Cell Res.
PUBLISHED: 01-02-2014
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It remains controversial whether the abnormal epigenetic modifications accumulated in the induced pluripotent stem cells (iPSCs) can ultimately affect iPSC pluripotency. To probe this question, iPSC lines with the same genetic background and proviral integration sites were established, and the pluripotency state of each iPSC line was characterized using tetraploid (4N) complementation assay. Subsequently, gene expression and global epigenetic modifications of "4N-ON" and the corresponding "4N-OFF" iPSC lines were compared through deep sequencing analyses of mRNA expression, small RNA profile, histone modifications (H3K27me3, H3K4me3, and H3K4me2), and DNA methylation. We found that methylation of an imprinted gene, Zrsr1, was consistently disrupted in the iPSC lines with reduced pluripotency. Furthermore, the disrupted methylation could not be rescued by improving culture conditions or subcloning of iPSCs. Moreover, the relationship between hypomethylation of Zrsr1 and pluripotency state of iPSCs was further validated in independent iPSC lines derived from other reprogramming systems.
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Rs7206790 and rs11644943 in FTO gene are associated with risk of obesity in Chinese school-age population.
PLoS ONE
PUBLISHED: 01-01-2014
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To evaluate the associations between candidate FTO single nucleotide polymorphisms (SNPs) and obesity, a case-control study was conducted among Chinese school-age children, which included 500 obese cases and 500 matched controls (age, gender and location). We selected 24 candidate FTO tag-SNPs via bio-informatics analysis and performed genotyping using SNPScan technology. Results indicated that rs7206790 and rs11644943 were significantly associated with obesity among school-age children in both additive and recessive models (P<0.05) after adjusting confounders. Comparing rs7206790 CC and CG genotype of carriers, those carrying the GG genotype had an increased risk of obesity (adjusted odds ratio [OR], 3.76; 95% Confidence interval [CI], 1.24-11.43). Carriers of the AA allele of rs11644943 had a lower risk of obesity (adjusted OR, 0.16; 95% CI, 0.04-0.72) compared with those of the T allele (TT and TA). These two SNPs (rs7206790 and rs11644943) were not Linkage Disequilibrium (LD) with previous reported obesity-associated SNPs. Under the recessive model adjusted for age and gender and location, rs7206790 GG allele carriers had significantly increased BMIs (P?=?0.012), weight (P?=?0.012), waist circumferences (WC) (P?=?0.045) and hip circumferences (HC) (P?=?0.033). Conversely, rs11644943 AA allele carriers had significantly decreased BMIs (P?=?0.006), WC (P?=?0.037) and Waist-to-height ratios (WHtR) (P?=?0.012). A dose-response relationship was found between the number of risk alleles in rs7206790, rs11644943 and rs9939609 and the risk of obesity. The Genetic Risk Score (GRS) of the reference group was 3; in comparison, those of 2, 4, and ?5 had ORs for obesity of 0.24 (95%CI, 0.05-1.13), 1.49 (95%CI, 1.10-2.01), and 5.20 (95%CI, 1.75-15.44), respectively. This study confirmed the role of FTO variation on genetic susceptibility to obesity. We reported two new obesity-related FTO SNPs (rs7206790 and rs11644943) among Chinese school-age children.
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Interface electronic structures of reversible double-docking self-assembled monolayers on an Au(111) surface.
Philos Trans A Math Phys Eng Sci
PUBLISHED: 01-01-2014
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Double-docking self-assembled monolayers (DDSAMs), namely self-assembled monolayers (SAMs) formed by molecules possessing two docking groups, provide great flexibility to tune the work function of metal electrodes and the tunnelling barrier between metal electrodes and the SAMs, and thus offer promising applications in both organic and molecular electronics. Based on the dispersion-corrected density functional theory (DFT) in comparison with conventional DFT, we carry out a systematic investigation on the dual configurations of a series of DDSAMs on an Au(111) surface. Through analysing the interface electronic structures, we obtain the relationship between single molecular properties and the SAM-induced work-function modification as well as the level alignment between the metal Fermi level and molecular frontier states. The two possible conformations of one type of DDSAM on a metal surface reveal a strong difference in the work-function modification and the electron/hole tunnelling barriers. Fermi-level pinning is found to be a key factor to understand the interface electronic properties.
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Aberrant DNA methylation of G-protein-coupled bile acid receptor Gpbar1 (TGR5) is a potential biomarker for hepatitis B Virus associated hepatocellular carcinoma.
Int J Med Sci
PUBLISHED: 01-01-2014
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G-protein-coupled bile acid receptor Gpbar1 (TGR5) is a newly identified liver tumor suppressor in carcinogenesis. This present study was therefore to determine the potential value of serum TGR5 promoter methylation in identifying hepatocellular carcinoma (HCC) from chronic hepatitis B (CHB) patients.
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Comparative pharmacokinetics of baicalin, wogonoside, baicalein and wogonin in plasma after oral administration of pure baicalin, radix scutellariae and scutellariae-paeoniae couple extracts in normal and ulcerative colitis rats.
Iran J Pharm Res
PUBLISHED: 11-20-2013
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The aim of this study was to investigate the pharmacokinetic profiles of baicalin, wogonoside, baicalein and wogonin after oral administration of pure baicalin, Radix scutellariae and Scutellariae-Paeoniae couple extracts were administered and the pharmacokinetics profiles were compared between normal and ulcerative colitis rats. The plasma concentrations of the four flavonoids were determined by using a simple and rapid high-performance liquid chromatography method. All the rats were divided randomly into two groups (ulcerative colitis and normal groups). Each group contained three subgroups: pure baicalin, Radix scutellariae and Scutellariae-Paeoniae couple extracts subgroup. Each group received oral administration of pure baicalin, Radix Scutellariae and Scutellariae-Paeoniae couple extracts at the same dose of 200 mg/kg baicalin. The results showed that wogonoside, possibily as a methylated product of baicalin, was found in plasma after oral administration of pure baicalin or formulas to rats. Baicalin and wogonoside demonstrated bimodal phenomenon. Baicalin and wogonoside in Scutellariae-Paeoniae couple extract had shown better absorption than which in pure baicalin and Radix Scutellariae extract. Whether oral administration of pure baicalin, Radix Scutellariae or Scutellariae-Paeoniae couple extracts, ulcerative colitis rats showed better absorption than normal rats. For example AUC (0-t) of baicalin were: (41.46 ± 0.62), (59.12 ± 6.42) and (104.87 ± 0.86) (?g/mL)·h in UC groups vs (17.77 ± 0.66), (28.04 ± 4.06) and (49.01 ± 4.61) (?g/mL)·h in normal groups, respectively. The pharmacokinetics properties of the four flavonoids differed between ulcerative colitis and normal rats, including AUC ( 0-t ) and Cmax (p < 0.05).
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Susceptibility baseline and chlorantraniliprole resistance monitoring in Chilo suppressalis (Lepidoptera: Pyralidae).
J. Econ. Entomol.
PUBLISHED: 11-15-2013
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Chlorantraniliprole, a new anthranilic diamide insecticide, has been commercialized in China since 2008 for controlling of several lepidopterans, including rice stem borer, Chilo suppressalis Walker. Chemical control of this pest has become difficult because of its resistance development to many conventional insecticides. To facilitate chlorantraniliprole-resistance monitoring, seedling dip bioassays were conducted in 2011 and 2012 to assess the susceptibility of 30 populations of C. suppressalis from seven provinces in China. The assays established a larval susceptibility baseline with LC50 at 1.393 mg a.i/liter. The toxicity (LC50) of chlorantraniliprole against second-instar larvae of field populations ranged from 0.568 (SL12) to 13.547 (RA12) mg a.i/liter. Substantial variations of the susceptibility to chlorantraniliprole were detected among different geographic populations, but no significant difference was observed between years for most populations except for populations from Dongan, Cangnan, and Lujiang. Resistance ratios to the chemical ranged from 1.0 to 9.7, indicating that most colonies remained susceptible or showed certain decrease in susceptibility. Approximately, 13.3% of the populations exhibited low levels of resistance to chlorantraniliprole. These data are useful in future monitoring program for detecting any changes in susceptibility as a result of use of the insecticide.
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Stretching single polymer chains of donor-acceptor foldamers: toward the quantitative study on the extent of folding.
Langmuir
PUBLISHED: 11-14-2013
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Single-molecule force spectroscopy has proven to be an efficient tool for the quantitative characterization of flexible foldamers on the single-molecule level in this study. The extent of folding has been estimated quantitatively for the first time to the best of our knowledge, which is crucial for a better understanding of the "folding-process" on single-molecule level. Therefore, this study may provide a guidance to regulate folding for realizing rational control over the functions of bulk materials.
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Bending effect on modal interference in a fiber taper and sensitivity enhancement for refractive index measurement.
Opt Express
PUBLISHED: 11-13-2013
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We demonstrate the bending effect of microfiber on interference fringes in a compact taper-based modal interferometer and sensitivity for refractive index (RI) measurement. For the bend curvature ranging from 0 to 0.283 mm(-1), the measured RI sensitivity distinctively increases from 342.5 nm/RIU (refractive-index unit) to 1192.7 nm/RIU around RI = 1.333 and from 3847.1 nm/RIU to 11006.0 nm/RIU around RI = 1.430, respectively. Theoretical analysis reveals that such enhancement is determined by the dispersion property of the intermodal index rather than other parameters, such as the variation of the straightforward evanescent field. The magnitude of sensitivity varies as a function of the microfiber bend curvature. Approaching a critical curvature (the intermodal-index dispersion factor approaches zero), the sensitivity is significantly enhanced, exhibiting great potential in RI sensing areas.
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TRV-GFP: a modified Tobacco rattle virus vector for efficient and visualizable analysis of gene function.
J. Exp. Bot.
PUBLISHED: 11-11-2013
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Virus-induced gene silencing (VIGS) is a useful tool for functional characterization of genes in plants. Unfortunately, the efficiency of infection by Tobacco rattle virus (TRV) is relatively low for some non-Solanaceae plants, which are economically important, such as rose (Rosa sp.). Here, to generate an easy traceable TRV vector, a green fluorescent protein (GFP) gene was tagged to the 3 terminus of the coat protein gene in the original TRV2 vector, and the silencing efficiency of the modified TRV-GFP vector was tested in several plants, including Nicotiana benthamiana, Arabidopsis thaliana, rose, strawberry (Fragaria ananassa), and chrysanthemum (Dendranthema grandiflorum). The results showed that the efficiency of infection by TRV-GFP was equal to that of the original TRV vector in each tested plant. Spread of the modified TRV virus was easy to monitor by using fluorescent microscopy and a hand-held UV lamp. When TRV-GFP was used to silence the endogenous phytoene desaturase (PDS) gene in rose cuttings and seedlings, the typical photobleached phenotype was observed in 75-80% plants which were identified as GFP positive by UV lamp. In addition, the abundance of GFP protein, which represented the concentration of TRV virus, was proved to correlate negatively with the level of the PDS gene, suggesting that GFP could be used as an indicator of the degree of silencing of a target gene. Taken together, this work provides a visualizable and efficient tool to predict positive gene silencing plants, which is valuable for research into gene function in plants, especially for non-Solanaceae plants.
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Deterministic growth of AgTCNQ and CuTCNQ nanowires on large-area reduced graphene oxide films for flexible optoelectronics.
Nanotechnology
PUBLISHED: 10-24-2013
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We describe a synchronous reduction and assembly procedure to directly produce large-area reduced graphene oxide (rGO) films sandwiched by a high density of metal nanoparticles (silver and copper). Further, by using the sandwiched metal NPs as sources, networks consisting of AgTCNQ and CuTCNQ nanowires were deterministically grown from the rGO films, forming structurally and functionally integrated rGO/metal-TCNQ hybrid films with outstanding flexibility, bending endurance, and electrical stability. Interestingly, due to the p-type nature of the rGO film and the n-type nature of the metal-TCNQ NWs, the hybrid films are essentially thin-film p-n junctions which are useful in ubiquitous electronics and optoelectronics. Measurements of the optoelectronic properties demonstrate that the rGO/metal-TCNQ hybrid films exhibit substantial photoconductivity and highly reproducible photoswitching behaviours. The present approach may open the door to the versatile and deterministic integration of functional nanostructures into flexible conducting substrates and provide an important step towards producing low-cost and high-performance soft electronic and optoelectronic devices.
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[Analysis of clinical features among severe or critical pregnant women in different trimesters with 2009 pandemic H1N1 infection].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 10-16-2013
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To explore the disease course and outcomes of severe or critical pregnant women with 2009 pandemic H1N1 (pH1N1) infection in China.
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A large-area diffuse air discharge plasma excited by nanosecond pulse under a double hexagon needle-array electrode.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 10-06-2013
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A large-area diffuse air discharge plasma excited by bipolar nanosecond pulse is generated under a double hexagon needle-array electrode at atmospheric pressure. The images of the diffuse discharge, electric characteristics, and the optical emission spectra emitted from the diffuse air discharge plasma are obtained. Based on the waveforms of pulse voltage and current, the power consumption, and the power density of the diffuse air discharge plasma are investigated under different pulse peak voltages. The electron density and the electron temperature of the diffuse plasma are estimated to be approximately 1.42×10(11)cm(-3) and 4.4eV, respectively. The optical emission spectra are arranged to determine the rotational and vibrational temperatures by comparing experimental with simulated spectra. Meanwhile, the rotational and vibrational temperatures of the diffuse discharge plasma are also discussed under different pulse peak voltages and pulse repetition rates, respectively. In addition, the diffuse air discharge plasma can form an area of about 70×50mm(2) on the surface of dielectric layer and can be scaled up to the required size.
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Curcumin inhibits human non-small cell lung cancer A549 cell proliferation through regulation of Bcl-2/Bax and cytochrome C.
Asian Pac. J. Cancer Prev.
PUBLISHED: 10-03-2013
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We intended to study the mechanism of the inhibitory action of curcumin on human non-small cell lung cancer A549 cell. The cell growth was determined by CCK-8 assay, and the results indicated that curcumin inhibited the cell proliferation in a concentration dependent manner. And to further confirm the relative anti-cancer mechanism of curcumin, RT-PCR was carried out to analysis the expression of relative apoptotic proteins Bax, Bcl-2. We found that curcumin could up-regulate the expression of Bax but down-regulate the expression of Bcl-2 in A549 cells. In addition, curcumin affect the mitochondrial apoptosis pathway. These results suggested that curcumin inhibited cancer cell growth through the regulation of Bcl-2/Bax and affect the mitochondrial apoptosis pathway.
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[Assessment of left ventricular systolic function with magnetic resonance imaging: comparison with that of echocardiography].
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi
PUBLISHED: 09-25-2013
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This study is designed to test the agreement in measuring left ventricular systolic function between transthoracic two-dimensional echocardiography (2DTTE) and "gold standard" of non-invasive cardiac imaging, magnetic resonance imaging (CMRI) and their impacts on the classification of patients according to the left ventricular ejection fraction (EF). 32 patients who were suspected with heart disease were evaluated by CMRI and 2DTTE examinations. End diastolic volume (EDV), end systolic volume (ESV), EF and left ventricular function category were then calculated and compared. There was no significant difference (P=0.504) for EDV, while ESV of CMRI was significantly higher than that of 2DTTE (P=0.049), and EF of CMRI was significantly lower than that of 2DTTE (P= 0.018). There was no significant difference (P=0.077) in left ventricular functional category. Bland-Altman analysis of LV volumetric data and EF measurements showed a good agreement between two methods. The 2DTTE over-estimated I (n=5) or II (n=1) degrees of functional classification when compared with the CMRI. Both CMRI and 2DTTE are of great clinical value in evaluating left ventricular systolic function, while CMR may be more beneficial to patients with abnormal LV functions.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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