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Find video protocols related to scientific articles indexed in Pubmed.
Synthetic-Method-Dependent Magnetic Relaxation in a Cobalt(II) Phosphonate Chain Compound.
Inorg Chem
PUBLISHED: 11-14-2014
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A polar cobalt(II) phosphonate Co(bamdpH2)(H2O) (1) [bamdpH4 = (benzylazanediyl)bis(methylene)diphosphonic acid] is reported. It shows a linear chain structure. The neighboring chains are connected by moderately strong hydrogen bonds forming a supramolecular layer. The interlayer spaces are filled with the organic groups of the phosphonate ligands. Compound 1 displays the coexistence of single-chain magnet behavior and canted antiferromagnetism below 2.8 K. Moreover, the magnetic dynamics is strongly dependent on the synthetic methods, a phenomenon that has not been documented before.
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Fast-track surgery for gastroenteric neoplasms: a meta-analysis.
Tumori
PUBLISHED: 10-25-2014
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Aims and background. Fast-track surgery has been shown to enhance postoperative recovery. The objective of the study was to determine the differences of fast-track surgery and conventional care for patients with gastroenteric neoplasms. Methods and study design. We searched PubMed, EMBASE, and the Cochrane Library for related trials to compare hospital stay and rates of complications and readmission. Results. Thirteen randomized controlled trials, with 1,962 patients, were included. Results showed the length of hospital stay was significantly reduced in the fast-track group. The complications rate was lowered in colorectal surgery. There were no significant differences in rate of readmissions. Conclusions. Current trials show that fast-track surgery may reduce the length of hospital stay and lower the rate of complications of gastroenteric surgery.
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Time-variant clustering model for understanding cell fate decisions.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 10-22-2014
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Both spatial characteristics and temporal features are often the subjects of concern in physical, social, and biological studies. This work tackles the clustering problems for time course data in which the cluster number and clustering structure change with respect to time, dubbed time-variant clustering. We developed a hierarchical model that simultaneously clusters the objects at every time point and describes the relationships of the clusters between time points. The hidden layer of this model is a generalized form of branching processes. A reversible-jump Markov Chain Monte Carlo method was implemented for model inference, and a feature selection procedure was developed. We applied this method to explore an open question in preimplantation embryonic development. Our analyses using single-cell gene expression data suggested that the earliest cell fate decision could start at the 4-cell stage in mice, earlier than the commonly thought 8- to 16-cell stage. These results together with independent experimental data from single-cell RNA-seq provided support against a prevailing hypothesis in mammalian development.
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EpilepsyGene: a genetic resource for genes and mutations related to epilepsy.
Nucleic Acids Res.
PUBLISHED: 10-18-2014
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Epilepsy is one of the most prevalent chronic neurological disorders, afflicting about 3.5-6.5 per 1000 children and 10.8 per 1000 elderly people. With intensive effort made during the last two decades, numerous genes and mutations have been published to be associated with the disease. An organized resource integrating and annotating the ever-increasing genetic data will be imperative to acquire a global view of the cutting-edge in epilepsy research. Herein, we developed EpilepsyGene (http://61.152.91.49/EpilepsyGene). It contains cumulative to date 499 genes and 3931 variants associated with 331 clinical phenotypes collected from 818 publications. Furthermore, in-depth data mining was performed to gain insights into the understanding of the data, including functional annotation, gene prioritization, functional analysis of prioritized genes and overlap analysis focusing on the comorbidity. An intuitive web interface to search and browse the diversified genetic data was also developed to facilitate access to the data of interest. In general, EpilepsyGene is designed to be a central genetic database to provide the research community substantial convenience to uncover the genetic basis of epilepsy.
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Real-time laser differential confocal microscopy without sample reflectivity effects.
Opt Express
PUBLISHED: 10-17-2014
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A new real-time laser differential confocal microscopy (RLDCM) without sample reflectivity difference effects is proposed for imaging height topography of sample surface, which divides the confocal microscopy imaging light path into two confocal microscopy imaging paths before and after focus with the equal axial detector offset oriented in opposite direction. By dividing the difference of the two signals simultaneously detected from these two confocal imaging paths by the higher signal between these two signals, RLDCM separates the signal that comes from reflectivity heterogeneity from the topographic signal in real time for the first time. RLDCM significantly reduces the height topography imaging time by single-layer scanning for the sample surface with reflectivity heterogeneity, and it achieves high axial resolution and lateral resolution similar to CM by optimizing the axial detector offset. Theoretical analysis and experimental results demonstrate that RLDCM realizes the real-time surface imaging for line structures featuring Silicon Dioxide steps on a Silicon base and achieves 2-nm axial depth resolution without reducing lateral resolution.
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Targeting the c-Met/FZD8 signaling axis eliminates patient-derived cancer stem-like cells in head and neck squamous carcinomas.
Cancer Res.
PUBLISHED: 10-17-2014
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Cancer stem-like cells (CSC) thought to contribute to head and neck squamous carcinomas (HNSCC) may offer attractive therapeutic targets if a tractable approach can be developed. In this study, we report that silencing c-Met is sufficient to suppress sphere formation, tumor initiation and metastatic properties of HN-CSC. Pharmacologic inhibition of c-Met with the selective inhibitor PF-2341066 preferentially targeted CSC and synergized with conventional chemotherapy to improve efficacy in a mouse xenograft model of HNSCC, impeding tumor growth and reducing metastasis. Mechanistic investigations showed that CSC elimination was due to downregulation of Wnt/?-catenin signaling in HN-CSC and that the Wnt pathway receptor FZD8 was essential for interactions of c-Met and Wnt/?-catenin signaling in HN-CSC. Notably, ectopic expression of FZD8 rescued the impaired phenotype of HN-CSC where c-Met was inhibited. Furthermore, c-Met upregulated FZD8 through the ERK/c-Fos cascade in HN-CSC. Taken together, our results offer a preclinical proof-of-concept for targeting the c-Met/FZD8 signaling axis as a CSC-directed therapy to improve HNSCC treatment.
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A Near-Infrared Dithieno[2,3-a:3',2'-c]phenazine-Based Organic Co-Sensitizer for Highly Efficient and Stable Quasi-Solid-State Dye-Sensitized Solar Cells.
ACS Appl Mater Interfaces
PUBLISHED: 10-17-2014
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A novel near-infrared (NIR) organic sensitizer FNE53 with a strong electron-withdrawing unit, dithieno[2,3-a:3',2'-c]phenazine, has been designed and synthesized for quasi-solid-state dye-sensitized solar cells (DSSCs). By simply fusing the two thiophene rings on quinoxaline unit in sensitizer FNE48, the intramolecular charge transfer (ICT) band bathochromically shifts from 542 nm for FNE48 to 629 nm for FNE53 in toluene solution. The absorption spectrum of sensitizer FNE53 covers the whole visible region and extends to the NIR region, which exhibits complementary absorption profile to another organic dye FNE46 based on quinoxaline. When FNE46 and FNE53 are used as cosensitizers for metal-free cocktail-type quasi-solid-state DSSCs, sensitizer FNE53 not only extends the photoresponse range but also suppresses the intermolecular interactions among the dye molecules. Therefore, the cocktail-type quasi-solid-state DSSC displays much higher IPCE value compared with that for the DSSC sensitizer based on FNE53 and a broader IPCE response in comparison to that for the DSSC sensitizers based on FNE46, respectively. After the molar ratio between the two cocktail dyes is optimized, the highest energy conversion efficiency of 8.04% is achieved in a metal-free quasi-solid-state DSSC cosensitized with FNE46 and FNE53, which exhibits good long-term stability after continuous light soaking for 1000 h.
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Why do people appear not to extrapolate trajectories during multiple object tracking? A computational investigation.
J Vis
PUBLISHED: 10-15-2014
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Intuitively, extrapolating object trajectories should make visual tracking more accurate. This has proven to be true in many contexts that involve tracking a single item. But surprisingly, when tracking multiple identical items in what is known as "multiple object tracking," observers often appear to ignore direction of motion, relying instead on basic spatial memory. We investigated potential reasons for this behavior through probabilistic models that were endowed with perceptual limitations in the range of typical human observers, including noisy spatial perception. When we compared a model that weights its extrapolations relative to other sources of information about object position, and one that does not extrapolate at all, we found no reliable difference in performance, belying the intuition that extrapolation always benefits tracking. In follow-up experiments we found this to be true for a variety of models that weight observations and predictions in different ways; in some cases we even observed worse performance for models that use extrapolations compared to a model that does not at all. Ultimately, the best performing models either did not extrapolate, or extrapolated very conservatively, relying heavily on observations. These results illustrate the difficulty and attendant hazards of using noisy inputs to extrapolate the trajectories of multiple objects simultaneously in situations with targets and featurally confusable nontargets.
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[Risk factors of benign anastomostic strictures after esophagectomy with cervical reconstruction].
Zhonghua Wei Chang Wai Ke Za Zhi
PUBLISHED: 10-03-2014
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To identify the risk factors of benign cervical anastomotic strictures after esophagectomy.
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[Effect of Gansui Banxia Tang plus-minus Gansui and Gancao anti-drug combination that preferred dose close to clinical application on diuretic effect in malignant ascites rats].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 10-03-2014
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To observe the effect of Gansui Banxia Tang plus-minus Gansui and Gancao anti-drug combination on hepatic and renal functions in malignant ascites rats to explore whether the efficacy or toxicity associated with the anti-drug combination.
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Cardiovascular dysfunction in offspring of ovarian hyperstimulated women and effects of estradiol and progesterone: a retrospective cohort study and proteomics analysis.
J. Clin. Endocrinol. Metab.
PUBLISHED: 10-01-2014
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Context: The cardiovascular dysfunction in children born with assisted reproductive technologies has been widely concerned. However, the association of ovarian hyperstimulation syndrome (OHSS), a complication of assisted reproductive technologies, with worse cardiovascular functions and underlying mechanism remain unknown. Objectives: To assess the cardiovascular functions of children born to mothers with OHSS and investigate the underlying regulator(s). Design and Setting: This was a retrospective cohort recruited in a university hospital. Participants and Methods: We assessed cardiovascular functions by Doppler echography in 42 children born to OHSS women, 34 children of mothers with non- OHSS In Vitro Fertilization (IVF) and 48 spontaneously conceived (SC) children (mean age about 4.5 years). Groups were matched for gestational age at delivery and birth weight. An iTRAQ labeled proteomics analysis was performed with another set of umbilical arteries from OHSS and SC pregnancies (n=3 for both groups). Results: Children of OHSS mothers showed a significantly decreased mitral E/A ratio, reduced systolic and diastolic diameters of common carotid arteries and impaired flow-mediated dilation compared with non-OHSS IVF and SC children. Intima-media thickness and arterial stiffness indices were similar in three groups. In proteomics study, 1640 proteins were identified from OHSS and SC umbilical arteries, and, 40 differentially expressed proteins were selected for further analysis. Estradiol and progesterone were identified as activated upstream regulators. Conclusions: Children born to ovarian hyperstimulated women displayed cardiovascular dysfunctions. The underlying mechanisms may involve the effects of supraphysiological estradiol and progesterone levels.
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A Bayesian framework to identify methylcytosines from high-throughput bisulfite sequencing data.
PLoS Comput. Biol.
PUBLISHED: 09-01-2014
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High-throughput bisulfite sequencing technologies have provided a comprehensive and well-fitted way to investigate DNA methylation at single-base resolution. However, there are substantial bioinformatic challenges to distinguish precisely methylcytosines from unconverted cytosines based on bisulfite sequencing data. The challenges arise, at least in part, from cell heterozygosis caused by multicellular sequencing and the still limited number of statistical methods that are available for methylcytosine calling based on bisulfite sequencing data. Here, we present an algorithm, termed Bycom, a new Bayesian model that can perform methylcytosine calling with high accuracy. Bycom considers cell heterozygosis along with sequencing errors and bisulfite conversion efficiency to improve calling accuracy. Bycom performance was compared with the performance of Lister, the method most widely used to identify methylcytosines from bisulfite sequencing data. The results showed that the performance of Bycom was better than that of Lister for data with high methylation levels. Bycom also showed higher sensitivity and specificity for low methylation level samples (<1%) than Lister. A validation experiment based on reduced representation bisulfite sequencing data suggested that Bycom had a false positive rate of about 4% while maintaining an accuracy of close to 94%. This study demonstrated that Bycom had a low false calling rate at any methylation level and accurate methylcytosine calling at high methylation levels. Bycom will contribute significantly to studies aimed at recalibrating the methylation level of genomic regions based on the presence of methylcytosines.
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Altered protein expression profiles in umbilical veins: insights into vascular dysfunctions of the children born after in vitro fertilization.
Biol. Reprod.
PUBLISHED: 08-06-2014
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Cardiovascular dysfunction and remodeling have been found in some children conceived by in vitro fertilization (IVF). However, the underlying mechanisms remain unclear. In this study, the retrospective investigation showed that the blood pressure of IVF-conceived Chinese children was higher than that of naturally conceived (NC) children at ages 3-13 yr. We analyzed the expression profile of proteins in the umbilical veins of IVF and NC newborns by proteomic techniques. Using iTRAQ (isobaric tags for relative and absolute quantitation), 47 differentially expressed proteins (DEPs) were identified by feature selection in IVF umbilical veins compared with NC. Ingenuity Pathway Analysis, which is used to explore the signaling pathways of DEPs, revealed that these DEPs played important roles in vascular system development and carbon metabolism, implying that these DEPs might be potential candidates for further exploration of the mechanism(s) of vascular dysfunction in IVF children. We found that the serum estradiol (E2) level in the cord blood of IVF newborns was significantly higher than that of NC newborns. High concentrations of E2 induced alteration of lumican and vimentin expression in human umbilical vein endothelial cells, which was consistent with the proteomic results. These findings suggested that abnormal expression of proteins in umbilical veins might be related to the cardiovascular dysfunction and remodeling in IVF offspring. In conclusion, our data for the first time reveal the protein expression profile in blood vessels of IVF offspring and provide information for further mechanism study and evaluation of risks of cardiovascular abnormality in IVF children.
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Cell fate inclination within 2-cell and 4-cell mouse embryos revealed by single-cell RNA sequencing.
Genome Res.
PUBLISHED: 08-05-2014
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It remains an open question when and how the first cell fate decision is made in mammals. Using deep single-cell RNA-seq of matched sister blastomeres, we report highly reproducible inter-blastomere differences among 10 2-cell and five 4-cell mouse embryos. Inter-blastomere gene expression differences dominated between-embryo differences and noise, and were sufficient to cluster sister blastomeres into distinct groups. Dozens of protein-coding genes exhibited reproducible bimodal expression in sister blastomeres, which cannot be explained by random fluctuations. The protein expression of one gene out of four of these bimodal genes tested, Gadd45a, exhibited clear inter-blastomeric contrasts. We traced some of the bimodal mRNA expressions to embryonic genome activation, and others to blastomere-specific RNA depletion. Inter-blastomere differences created coexpression gene networks that were much stronger and larger than those that can possibly be created by random noise. The highly correlated gene pairs at the 4-cell stage overlapped with those showing the same directions of differential expression between inner cell mass (ICM) and trophectoderm (TE). These data substantiate the hypothesis of inter-blastomere differences in 2- and 4-cell mouse embryos, and associate these differences with ICM/TE differences.
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Homochiral Cobalt Phosphonates Containing ?-type Chains with a Tunable Interlayer Distance and a Field-Induced Phase Transition.
Chemistry
PUBLISHED: 07-27-2014
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Two pairs of enantiomeric Co(II) compounds with formulas [Co2 (?3 -OH)(cyamp)(Cn H2n+1 COO)] (cyampH2 =(S)- or (R)-[(1-cyclohexylethyl)amino]methylphosphonic acid; n=1 (1); n=7 (2)) were synthesized. The structures of S-1 and S-2 were determined by single-crystal structural analyses. Both crystallize in a monoclinic chiral space group P21 , and exhibit layered structures in which the ?-type chains of corner-sharing Co3 (?3 -OH) triangles are connected by the phosphonate groups. The interlayer spaces are filled with the organic groups of the phosphonate and carboxylate ligands. Therefore, the distances between the layers can be manipulated by the length of the alkyl chain of the carboxylate ligands, from 14.6?Å in 1 to 20.0?Å in 2. Magnetic studies were carried out for compounds S-1 and S-2. Both show metamagnetism at low temperature. The critical field decreases with increasing interlayer distance from 8.18?kOe for S-1 to 7.01?kOe for S-2 at 1.8?K. The optical properties were also studied.
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Controlling the charge transfer in D-A-D chromophores based on pyrazine derivatives.
J. Org. Chem.
PUBLISHED: 07-01-2014
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A series of symmetrical donor-acceptor-donor (D-A-D) chromophores bearing various electron-withdrawing groups, such as quinoxaline (Qx), benzo[g]quinoxaline (BQ), phenazine (Pz), benzo[b]phenazine (BP), thieno[3,4-b]pyrazine (TP), and thieno[3,4-b]quinoxaline (TQ), has been designed and synthesized. Intramolecular charge transfer (ICT) interactions can be found for all the chromophores due to the electron-withdrawing properties of the two imine nitrogens in the pyrazine ring and the electron-donating properties of the other two amine nitrogens in the two triphenylamines. Upon the fusion of either benzene or thiophene ring on the pyrazine acceptor unit, the ICT interactions are strengthened, which results in the bathochromically shifted ICT band. Moreover, the thiophene ring is superior to the benzene ring in enlarging the ICT interaction and expanding the absorption spectrum. Typically, when a thiophene ring is fused on the Qx unit in DQxD, a near-infrared dye is realized in simple chromophore DTQD, which displays the maximum absorption wavelength at 716 nm with the threshold over 900 nm. This is probably due to the enhanced charge density on the acceptor moiety and better orbital overlap, as revealed by theoretical calculation. These results suggest that extending the conjugation of a pyrazine acceptor in an orthogonal direction to the D-A-D backbone can dramatically improve the ICT interactions.
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Small-conductance, calcium-activated potassium channel 3 (SK3) is a modulator of endometrial remodeling during endometrial growth.
J. Clin. Endocrinol. Metab.
PUBLISHED: 06-30-2014
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Small-conductance, Ca(2+)-activated K(+) channel 3 (SK3) has been shown to be expressed in porcine endometrium. However, the roles of SK3 in human endometrium during the menstrual cycle and early pregnancy are unknown.
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Synthesis of POSS-based ionic conductors with low glass transition temperatures for efficient solid-state dye-sensitized solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 06-23-2014
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Replacing liquid-state electrolytes with solid-state electrolytes has been proven to be an effective way to improve the durability of dye-sensitized solar cells (DSSCs). We report herein the synthesis of amorphous ionic conductors based on polyhedral oligomeric silsesquioxane (POSS) with low glass transition temperatures for solid-state DSSCs. As the ionic conductor is amorphous and in the elastomeric state at the operating temperature of DSSCs, good pore filling in the TiO2 film and good interfacial contact between the solid-state electrolyte and the TiO2 film can be guaranteed. When the POSS-based ionic conductor containing an allyl group is doped with only iodine as the solid-state electrolyte without any other additives, power conversion efficiency of 6.29% has been achieved with good long-term stability under one-sun soaking for 1000 h.
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Gene therapy in pancreatic cancer.
World J. Gastroenterol.
PUBLISHED: 06-12-2014
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Pancreatic cancer (PC) is a highly lethal disease and notoriously difficult to treat. Only a small proportion of PC patients are eligible for surgical resection, whilst conventional chemoradiotherapy only has a modest effect with substantial toxicity. Gene therapy has become a new widely investigated therapeutic approach for PC. This article reviews the basic rationale, gene delivery methods, therapeutic targets and developments of laboratory research and clinical trials in gene therapy of PC by searching the literature published in English using the PubMed database and analyzing clinical trials registered on the Gene Therapy Clinical Trials Worldwide website (http://www. wiley.co.uk/genmed/ clinical). Viral vectors are main gene delivery tools in gene therapy of cancer, and especially, oncolytic virus shows brighter prospect due to its tumor-targeting property. Efficient therapeutic targets for gene therapy include tumor suppressor gene p53, mutant oncogene K-ras, anti-angiogenesis gene VEGFR, suicide gene HSK-TK, cytosine deaminase and cytochrome p450, multiple cytokine genes and so on. Combining different targets or combination strategies with traditional chemoradiotherapy may be a more effective approach to improve the efficacy of cancer gene therapy. Cancer gene therapy is not yet applied in clinical practice, but basic and clinical studies have demonstrated its safety and clinical benefits. Gene therapy will be a new and promising field for the treatment of PC.
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Differential proteomic analysis of umbilical artery tissue from preeclampsia patients, using iTRAQ isobaric tags and 2D nano LC-MS/MS.
J Proteomics
PUBLISHED: 06-10-2014
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Epidemiological studies suggest that the impact of preeclampsia does not only affect the mother but also the children. We know that adverse events in utero may predispose individuals to premature cardiovascular disease in adulthood, but we do not know the mechanisms. To gain insights into the mechanisms of cardiovascular dysfunction in the offspring of preeclampsia, we employed a global stable isotope labeled profiling strategy using iTRAQ reagents, followed by 2D-LC-MS/MS. We identified 1521 non-redundant proteins, and 1496 of these were quantified. Further analysis identified 53 differentially expressed proteins in umbilical artery; 22 proteins were up-regulated and 31 proteins were down-regulated. K-means clustering analysis showed that there was a specific protein expression profile in the umbilical artery which could distinguish between normal and preeclampsia patients. These 53 proteins were analyzed by Ingenuity Pathway Analysis (IPA) and were found to play important roles in the angiogenesis, vasculogenesis, and development of the cardiovascular system. In addition, the differential expression of three cardiovascular relative proteins (aldose reductase, fibronectin-1, fibrillin-1) was independently verified using western blot. These results may supply new insights into the mechanisms of vascular dysfunction in the offspring of preeclampsia patients.
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Production and characterization of polypropylene composites filled with glass fibre recycled from pyrolysed waste printed circuit boards.
Environ Technol
PUBLISHED: 05-27-2014
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Waste printed circuit boards (WPCBs) are composed of nearly 70% non-metals, which are generally recycled as low-value filling materials or even directly dumped in landfills. In this study, polypropylene (PP) composites reinforced by recycled pure glass fibres (RGF) from pyrolysed WPCBs were successfully produced. The manufacturing process, mechanical properties and thermal behaviour of the composites were investigated. The results showed that the appropriate addition of RGF in the composites can significantly improve the mechanical properties and thermal behaviour. When the added content of RGF was 30%, the maximum increment of tensile strength, impact strength, flexural strength and flexural modulus of the glass fibre (GF)/PP composites are 25.93%, 41.38%, 31.16% and 68.42%, respectively, and the vicat softening temperature could rise by 4.6°C. Furthermore, leaching of the GF/PP composites was also investigated. The GF/PP composites exhibited high performance and non-toxicity, offering a promising method to recycle RGF from pyrolysed WPCBs with high-value applications.
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Enhanced proliferation in colorectal epithelium of patients with type 2 diabetes correlates with ?-catenin accumulation.
J. Diabetes Complicat.
PUBLISHED: 05-06-2014
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?-Catenin accumulation promotes proliferation. However, the correlation between proliferation of colorectal epithelium and ?-catenin in type 2 diabetes mellitus (DM) patients remains unclear.
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Ion/water channels for embryo implantation barrier.
Physiology (Bethesda)
PUBLISHED: 05-03-2014
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Successful implantation involves three distinct processes, namely the embryo apposition, attachment, and penetration through the luminal epithelium of the endometrium to establish a vascular link to the mother. After penetration, stromal cells underlying the epithelium differentiate and surround the embryo to form the embryo implantation barrier, which blocks the passage of harmful substances to the embryo. Many ion/water channel proteins were found to be involved in the process of embryo implantation. First, ion/water channel proteins play their classical role in establishing a resting membrane potential, shaping action potentials and other electrical signals by gating the flow of ions across the cell membrane. Second, most of ion/water channel proteins are regulated by steroid hormone (estrogen or progesterone), which may have important implications to the embryo implantation. Last but not least, these proteins do not limit themselves as pure channels but also function as an initiator of a series of consequences once activated by their ligand/stimulator. Herein, we discuss these new insights in recent years about the contribution of ion/water channels to the embryo implantation barrier construction during early pregnancy.
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Association of Serum Levels of CEA, CA199, CA125, CYFRA21-1 and CA72-4 and Disease Characteristics in Colorectal Cancer.
Pathol. Oncol. Res.
PUBLISHED: 04-24-2014
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Identifying predictive biomarkers for colorectal cancer would facilitate diagnosis and treatment of the disease. This study aimed to investigate the association of the serological biomarkers CEA, CA19-9, CA125, CYFRA21-1 and CA72-4 with patient characteristics and disease outcomes in colorectal cancer. Patients (N?=?373) with colorectal cancer were evaluated for the association of CEA, CA19-9, CA125, CYFRA21-1, and CA72-4 pre and post-surgery and at disease recurrence with demographics, disease characteristics including pathological types, degree of differentiation, invasion depth, abdominal lymph node metastasis, TMN stage, Dukes stage, location of cancer and metastasis, and disease outcomes. It was more common for a patient to express these markers prior to surgery and at disease recurrence than following surgery. Overall, the serum levels of CEA, CA19-9, CA125, CYFRA21-1, and CA72-4 were not associated with age, gender, pathological type and location of cancer (all P-values >0.05), but were associated with the poor tumor differentiation, higher tumor invasion, greater degree of abdominal lymph node metastasis, and higher TNM and Duke stage tumors (all P-values?
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Overexpression of Nedd9 is a prognostic marker of human gastric cancer.
Med. Oncol.
PUBLISHED: 04-14-2014
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The present study was designed to evaluate the expression and prognostic significance of neural precursor cell-expressed, developmentally downregulated 9 (Nedd9) in patients with gastric cancer. Overexpression of Nedd9 was detected in a number of human cancers and was associated with progression and poor prognosis of the diseases. The expression of Nedd9 and focal adhesion kinase (FAK) were detected using the tissue microarray technique and immunohistochemical method and compared with clinicopathological parameters of patients with gastric cancer. The expressions of Nedd9 and FAK were upregulated in gastric cancer lesions compared with their expression in adjacent non-malignant tissues. High expression of Nedd9 correlated with age, location of tumor, tumor size, depth of invasion, vessel invasion, lymph node metastasis, and distant metastasis, and also with expression of FAK. Further, multivariate analysis suggested that expression of Nedd9 and FAK were independent prognostic indicators for gastric cancer. Cumulative 5-year survival rates of patients with high expression of both Nedd9 and FAK was significantly lower than those with low expression of both. Nedd9 was implicated in the progression of gastric cancer. Based on the TNM stage, Nedd9 and FAK proteins could be useful prognostic marker to predict tumor progression and prognosis in gastric cancer.
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Ras-induced epigenetic inactivation of the RRAD (Ras-related associated with diabetes) gene promotes glucose uptake in a human ovarian cancer model.
J. Biol. Chem.
PUBLISHED: 03-19-2014
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RRAD (Ras-related associated with diabetes) is a small Ras-related GTPase that is frequently inactivated by DNA methylation of the CpG island in its promoter region in cancer tissues. However, the role of the methylation-induced RRAD inactivation in tumorigenesis remains unclear. In this study, the Ras-regulated transcriptome and epigenome were profiled by comparing T29H (a Ras(V12)-transformed human ovarian epithelial cell line) with T29 (an immortalized but non-transformed cell line) through reduced representation bisulfite sequencing and digital gene expression. We found that Ras(V12)-mediated oncogenic transformation was accompanied by RRAD promoter hypermethylation and a concomitant loss of RRAD expression. In addition, we found that the RRAD promoter was hypermethylated, and its transcription was reduced in ovarian cancer versus normal ovarian tissues. Treatment with the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine resulted in demethylation in the RRAD promoter and restored RRAD expression in T29H cells. Additionally, treatment with farnesyltransferase inhibitor FTI277 resulted in restored RRAD expression and inhibited DNA methytransferase expression and activity in T29H cells. By employing knockdown and overexpression techniques in T29 and T29H, respectively, we found that RRAD inhibited glucose uptake and lactate production by repressing the expression of glucose transporters. Finally, RRAD overexpression in T29H cells inhibited tumor formation in nude mice, suggesting that RRAD is a tumor suppressor gene. Our results indicate that Ras(V12)-mediated oncogenic transformation induces RRAD epigenetic inactivation, which in turn promotes glucose uptake and may contribute to ovarian cancer tumorigenesis.
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MiR-5000-3p, miR-5009-3P and miR-552: potential microRNA biomarkers of side population cells in colon cancer.
Oncol. Rep.
PUBLISHED: 03-17-2014
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Colon cancer is one of the most common cancers in the world. Multidrug resistance is related to poor prognosis of advanced colon cancer. The side population plays an important role in multiple drug resistance (MDR) of colon cancer. MicroRNA biomarkers of the side population of colon cancer is still unknown. In the present study, we aimed to explore miRNA markers of side population (SP) cells of colon cancer. The side population was sorted by flow cytometry. Cell viability was measured using an MTT assay. MicroRNA profiling analysis was performed to compare microRNA expression levels in the SP cells of colon cancer with levels in the non-SP cells of colon cancer. RT-PCR was applied to verify the result obtained from the microRNA profiling analysis. miR-5000-3p, miR-5009-3P and miR-552 were all found to be upregulated in SP cells of the colon cancer cell lines HCT-15, HT-29 and LoVo. RT-PCR confirmed the result from the microRNA profiling analysis. This implied that miR-5000-3p, miR-5009-3P and miR-552 may be potential microRNA biomarkers of the side population in colon cancer, which may provide new specific targets of the side population for the reversal of MDR of colon cancer.
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Separating the redox couple for highly efficient solid-state dye-sensitized solar cells.
Phys Chem Chem Phys
PUBLISHED: 03-14-2014
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To minimize the charge recombination between electrons and the electron acceptor in solid-state dye-sensitized solar cells, we propose a separated electron donor and acceptor of a redox couple in the photoanode and in the cathode, respectively. Owing to the absence of the acceptor in the photoanode initially, the charge recombination rate is retarded remarkably, resulting in an increase of the short-circuit photocurrent by >2-fold, open-circuit photovoltage by 71 mV and power conversion efficiency by >2.5-fold.
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Effect of structural isomerism on magnetic dynamics: from single-molecule magnet to single-chain magnet.
Inorg Chem
PUBLISHED: 03-04-2014
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This Paper reports the first examples of O-P-O bridged Mn2(salen)2 (salen = N,N'-bis(salicylidene)ethylenediamine) chain compounds, namely, [Mn2(salen)2(2-FC6H4PO3H)](ClO4)·1/2CH3OH (1) and [Mn2(salen)2(4-FC6H4PO3H)](ClO4) (2). The phosphonate ligands adopt a syn-anti bidentate bridging mode in 1 and a syn-syn bidentate bridging mode in 2, originated from the isomeric phosphonate ligands. The different bridging modes cause a significant change in the Mn-O···O-Mn torsion angle over the O-P-O bridge, which are 96.6 and 1.9° for 1 and 2, respectively. As a result, the antiferromagnetic (AF) exchange couplings mediated through the O-P-O pathway are extremely weak in 1, and the overall magnetic behaviors are dominated by the Mn2(salen)2 moieties. Single-molecule magnetic behavior is observed in 1. For compound 2, the AF interaction over the O-P-O bridge is much stronger. The coexistence of metamagnetism and single-chain magnetic behavior is observed for 2.
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High maternal serum estradiol environment in the first trimester is associated with the increased risk of small-for-gestational-age birth.
J. Clin. Endocrinol. Metab.
PUBLISHED: 02-28-2014
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There are increasing concerns that a disrupted endocrine environment may disturb the growth of the fetus. Assisted reproductive technology (ART) situates gamete/embryo in a supraphysiological estradiol (E2) environment and, thus, provides an ideal model to investigate this problem.
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From genomes to societies: a holistic view of determinants of human health.
Curr. Opin. Biotechnol.
PUBLISHED: 02-22-2014
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Both biological and social sciences have identified contributing factors to human health. However, health outcomes are unlikely to equal a simple sum of these identified factors. This article makes an attempt to put together the information, methods, and technologies that relate to health outcomes from biological, behavioral, and social disciplines. Much of this information was obtained by controlling for the variations of the factors in 'other' disciplines. For example, genetic factors were controlled for in identifying the behavioral determinants of health. Looking forward, better understandings of health outcomes may require exploiting the interactions of health determinants that were identified from different disciplines. We propose the concept of 'systems health' studies, which take health outcomes as the outputs of a system, where the inputs and their interactions from multiple disciplines are considered.
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MiR-125b promotes cell migration and invasion by targeting PPP1CA-Rb signal pathways in gastric cancer, resulting in a poor prognosis.
Gastric Cancer
PUBLISHED: 02-20-2014
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MiR-125b functions as an oncogene in many cancers; however, its clinical significance and molecular mechanism in gastric cancers have never been sufficiently investigated. Here, we elucidated the functions and molecular regulated pathways of MiR-125b in gastric cancer.
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A simple method for construction of artificial microRNA vector in plant.
Biotechnol. Lett.
PUBLISHED: 02-20-2014
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Artificial microRNA (amiRNA) is a powerful tool for silencing genes in many plant species. Here we provide an easy method to construct amiRNA vectors that reinvents the Golden Gate cloning approach and features a novel system called top speed amiRNA construction (TAC). This speedy approach accomplishes one restriction-ligation step in only 5 min, allowing easy and high-throughput vector construction. Three primers were annealed to be a specific adaptor, then digested and ligated on our novel vector pTAC. Importantly, this method allows the recombined amiRNA constructs to maintain the precursor of osa-miR528 with exception of the desired amiRNA/amiRNA* sequences. Using this method, our results showed the expected decrease of targeted genes in Nicotiana benthamiana and Oryza sativa.
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Rosiglitazone causes cardiotoxicity via peroxisome proliferator-activated receptor ?-independent mitochondrial oxidative stress in mouse hearts.
Toxicol. Sci.
PUBLISHED: 01-21-2014
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This study aims to test the hypothesis that thiazolidinedione rosiglitazone (RSG), a selective peroxisome proliferator-activated receptor ? (PPAR?) agonist, causes cardiotoxicity independently of PPAR?. Energy metabolism and mitochondrial function were measured in perfused hearts isolated from C57BL/6, cardiomyocyte-specific PPAR?-deficient mice, and their littermates. Cardiac function and mitochondrial oxidative stress were measured in both in vitro and in vivo settings. Treatment of isolated hearts with RSG at the supratherapeutic concentrations of 10 and 30 ?M caused myocardial energy deficiency as evidenced by the decreases in [PCr], [ATP], ATP/ADP ratio, energy charge with a concomitant cardiac dysfunction as indicated by the decreases in left ventricular systolic pressure, rates of tension development and relaxation, and by an increase in end-diastolic pressure. When incubated with tissue homogenate or isolated mitochondria at these same concentrations, RSG caused mitochondrial dysfunction as evidenced by the decreases in respiration rate, substrate oxidation rates, and activities of complexes I and IV. RSG also increased complexes I- and III-dependent O?? production, decreased glutathione content, inhibited superoxide dismutase, and increased the levels of malondialdehyde, protein carbonyl, and 8-hydroxy-2-deoxyguanosine in mitochondria, consistent with oxidative stress. N-acetyl-L-cysteine (NAC) 20 mM prevented RSG-induced above toxicity at those in vitro settings. Cardiomyocyte-specific PPAR? deletion and PPAR? antagonist GW9662 did not prevent the observed cardiotoxicity. Intravenous injection of 10 mg/kg RSG also caused cardiac dysfunction and oxidative stress, 600 mg/kg NAC antagonized these adverse effects. In conclusion, this study demonstrates that RSG at supratherapeutic concentrations causes cardiotoxicity via a PPAR?-independent mechanism involving oxidative stress-induced mitochondrial dysfunction in mouse hearts.
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Erlotinib in a patient with vaginal carcinoma and pulmonary metastasis: A case report.
Oncol Lett
PUBLISHED: 01-15-2014
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Erlotinib is an epidermal growth factor receptor tyrosine kinase inhibitor. It is widely used in the treatment of advanced non-small cell lung cancer and pancreatic cancer. However, there are currently no reports of the efficacy of erlotinib in patients with metastatic vaginal carcinoma. A 48-year-old female with vaginal carcinoma was diagnosed with lung metastasis four years following surgery. The patient received three cycles of chemotherapy but could not tolerate further treatment due to the side effects. Next, erlotinib was administered, prompting a partial response and disease stabilization for 9 months prior to disease progression. While the main treatments for vaginal carcinoma with distant metastasis are chemotherapy and radiotherapy, this case supplies preliminary evidence that erlotinib may have activity in these patients. Further studies are required to determine the potential of this therapy.
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Intermittent pneumatic compression pump for breast cancer-related lymphedema: a systematic review and meta-analysis of randomized controlled trials.
Oncol Res Treat
PUBLISHED: 01-07-2014
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Breast cancer-related lymphedema (BCRL) is a common complication after the treatment of breast cancer. The objective of this study was to determine whether the use of an intermittent pneumatic pump (IPC) could manage lymphedema effectively.
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POSS with eight imidazolium iodide arms for efficient solid-state dye-sensitized solar cells.
Chem. Commun. (Camb.)
PUBLISHED: 01-06-2014
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Polyhedral oligomeric silsesquioxane functionalized with eight imidazolium iodide arms has been designed and synthesized for use as solid-state electrolytes in solid-state dye-sensitized solar cells, which exhibits a power conversion efficiency of 7.11% under one sun illumination and good long-term stability under one sun soaking.
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Comparative epigenomics: defining and utilizing epigenomic variations across species, time-course, and individuals.
Wiley Interdiscip Rev Syst Biol Med
PUBLISHED: 01-05-2014
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Epigenomic profiling, by revealing genome-wide distributions of epigenetic modifications, generated a large amount of structural information about the chromosomes. Epigenomic analysis has quickly become a big data science, posing tremendous challenges on its translation into knowledge. To meet this challenge, comparative analysis of epigenomes, dubbed comparative epigenomics, has emerged as an active research area. Here, we summarize the recent developments in comparative epigenomic analyses into three major directions, namely the comparisons across species, the time-course of a biological process, and individuals. We review the main ideas, methods, and findings in each direction, and discuss the implications to understanding the regulatory functions of the genomes.
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Myeloid mineralocorticoid receptor deficiency inhibits aortic constriction-induced cardiac hypertrophy in mice.
PLoS ONE
PUBLISHED: 01-01-2014
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Mineralocorticoid receptor (MR) blockade has been shown to suppress cardiac hypertrophy and remodeling in animal models of pressure overload (POL). This study aims to determine whether MR deficiency in myeloid cells modulates aortic constriction-induced cardiovascular injuries. Myeloid MR knockout (MMRKO) mice and littermate control mice were subjected to abdominal aortic constriction (AAC) or sham operation. We found that AAC-induced cardiac hypertrophy and fibrosis were significantly attenuated in MMRKO mice. Expression of genes important in generating reactive oxygen species was decreased in MMRKO mice, while that of manganese superoxide dismutase increased. Furthermore, expression of genes important in cardiac metabolism was increased in MMRKO hearts. Macrophage infiltration in the heart was inhibited and expression of inflammatory genes was decreased in MMRKO mice. In addition, aortic fibrosis and inflammation were attenuated in MMRKO mice. Taken together, our data indicated that MR deficiency in myeloid cells effectively attenuated aortic constriction-induced cardiac hypertrophy and fibrosis, as well as aortic fibrosis and inflammation.
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Self-organization of mesoscopic silver wires by electrochemical deposition.
Beilstein J Nanotechnol
PUBLISHED: 01-01-2014
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Long, straight mesoscale silver wires have been fabricated from AgNO3 electrolyte via electrodeposition without the help of templates, additives, and surfactants. Although the wire growth speed is very fast due to growth under non-equilibrium conditions, the wire morphology is regular and uniform in diameter. Structural studies reveal that the wires are single-crystalline, with the [112] direction as the growth direction. A possible growth mechanism is suggested. Auger depth profile measurements show that the wires are stable against oxidation under ambient conditions. This unique system provides a convenient way for the study of self-organization in electrochemical environments as well as for the fabrication of highly-ordered, single-crystalline metal nanowires.
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A genetically-encoded YFP sensor with enhanced chloride sensitivity, photostability and reduced ph interference demonstrates augmented transmembrane chloride movement by gerbil prestin (SLC26a5).
PLoS ONE
PUBLISHED: 01-01-2014
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Chloride is the major anion in cells, with many diseases arising from disordered Cl- regulation. For the non-invasive investigation of Cl- flux, YFP-H148Q and its derivatives chameleon and Cl-Sensor previously were introduced as genetically encoded chloride indicators. Neither the Cl- sensitivity nor the pH-susceptibility of these modifications to YFP is optimal for precise measurements of Cl- under physiological conditions. Furthermore, the relatively poor photostability of YFP derivatives hinders their application for dynamic and quantitative Cl- measurements. Dynamic and accurate measurement of physiological concentrations of chloride would significantly affect our ability to study effects of chloride on cellular events.
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Understanding variation in transcription factor binding by modeling transcription factor genome-epigenome interactions.
PLoS Comput. Biol.
PUBLISHED: 12-01-2013
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Despite explosive growth in genomic datasets, the methods for studying epigenomic mechanisms of gene regulation remain primitive. Here we present a model-based approach to systematically analyze the epigenomic functions in modulating transcription factor-DNA binding. Based on the first principles of statistical mechanics, this model considers the interactions between epigenomic modifications and a cis-regulatory module, which contains multiple binding sites arranged in any configurations. We compiled a comprehensive epigenomic dataset in mouse embryonic stem (mES) cells, including DNA methylation (MeDIP-seq and MRE-seq), DNA hydroxymethylation (5-hmC-seq), and histone modifications (ChIP-seq). We discovered correlations of transcription factors (TFs) for specific combinations of epigenomic modifications, which we term epigenomic motifs. Epigenomic motifs explained why some TFs appeared to have different DNA binding motifs derived from in vivo (ChIP-seq) and in vitro experiments. Theoretical analyses suggested that the epigenome can modulate transcriptional noise and boost the cooperativity of weak TF binding sites. ChIP-seq data suggested that epigenomic boost of binding affinities in weak TF binding sites can function in mES cells. We showed in theory that the epigenome should suppress the TF binding differences on SNP-containing binding sites in two people. Using personal data, we identified strong associations between H3K4me2/H3K9ac and the degree of personal differences in NF?B binding in SNP-containing binding sites, which may explain why some SNPs introduce much smaller personal variations on TF binding than other SNPs. In summary, this model presents a powerful approach to analyze the functions of epigenomic modifications. This model was implemented into an open source program APEG (Affinity Prediction by Epigenome and Genome, http://systemsbio.ucsd.edu/apeg).
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Discovery of the surface polarity gradient on iridescent Morpho butterfly scales reveals a mechanism of their selective vapor response.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 09-09-2013
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For almost a century, the iridescence of tropical Morpho butterfly scales has been known to originate from 3D vertical ridge structures of stacked periodic layers of cuticle separated by air gaps. Here we describe a biological pattern of surface functionality that we have found in these photonic structures. This pattern is a gradient of surface polarity of the ridge structures that runs from their polar tops to their less-polar bottoms. This finding shows a biological pattern design that could stimulate numerous technological applications ranging from photonic security tags to self-cleaning surfaces, gas separators, protective clothing, sensors, and many others. As an important first step, this biomaterial property and our knowledge of its basis has allowed us to unveil a general mechanism of selective vapor response observed in the photonic Morpho nanostructures. This mechanism of selective vapor response brings a multivariable perspective for sensing, where selectivity is achieved within a single chemically graded nanostructured sensing unit, rather than from an array of separate sensors.
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Facile and selective synthesis of oligothiophene-based sensitizer isomers: an approach toward efficient dye-sensitized solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 09-09-2013
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Two sets of isomeric organic dyes with n-hexyl (DH and AH) or 2-ethylhexyl (DEH and AEH) groups substituted at the spacer part have been designed and straightforwardly synthesized via a facile and selective synthetic route. The structure difference between the isomers stands at the position of the incorporated alkyl chains which are introduced into the terthiophene spacer close to the donor (D) or anchor (A) side. The relationship between the isomeric structures and the optoelectronic properties are systematically investigated. It is found that, in the D series dyes, the alkyl group is much closer to the aromatic donor moiety, which brings about strong steric hindrance and therefore causes a remarkable twist in the molecular skeleton. In contrast, a more planar chemical structure and more effective ?-conjugation are realized in the A series dye isomers. Consequently, the A series isomeric dyes demonstrate bathochromically shifted absorption bands, resulting in the improved light-harvesting capability and enhanced photo-generated current. However, the D series isomeric dyes with more twisted molecular skeleton have suppressed the intermolecular interactions and retarded the charge recombination more efficiently, which induces higher open-circuit photovoltage. Combining the two effects on the performance of the fabricated dye-sensitized solar cells (DSSC), the influence from the short-circuit photocurrent plays a more significant role on the power conversion efficiency (?). As a result, isomer AEH-based DSSC with quasi-solid-state electrolyte displays the highest ? of 7.10% which remained at 98% of the initial value after continuous light soaking for 1000 h. Promisingly, a ? of 8.66% has been achieved for AEH-based DSSC with liquid electrolyte containing Co(II)/(III) redox couple. This work presents the crucial issue of molecular engineering and paves a way to design organic sensitizers for highly efficient and stable DSSCs.
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Hydroxyethyl and ester co-functionalized imidazolium iodide for highly efficient solid-state dye-sensitized solar cells.
Chem. Commun. (Camb.)
PUBLISHED: 09-07-2013
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Hydroxyethyl and ester co-functionalized imidazolium iodide has been designed and synthesized as an efficient solid state electrolyte for dye-sensitized solar cells. Single crystal X-ray analyses confirm the presence of ordered three dimensional ionic channels for iodide, which exhibits high conductivity when mixed with iodine and LiI and achieves a power conversion efficiency of 7.45%.
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Ionic conductor with high conductivity as single-component electrolyte for efficient solid-state dye-sensitized solar cells.
J. Am. Chem. Soc.
PUBLISHED: 08-19-2013
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Imidazolium iodide is an often used component in iodine-based dye-sensitized solar cells (DSSCs), but it cannot operate an efficient DSSC in the absence of iodine due to its low conductivity. For this study, lamellar solid iodide salts of imidazolium or piperidinium with an N-substituted propargyl group have been prepared and applied in solid-state DSSCs. Owing to the high conductivity arising from the lamellar structure, these solid-state ionic conductors can be used as single-component solid electrolytes to operate solid-state DSSCs efficiently without any additives in the electrolyte and post-treatments on the dye-loaded TiO2 films. With a propargyl group attached to the imidazolium ring, the conductivity is enhanced by about 4 × 10(4)-fold as compared to the alkyl-substituted imidazolium iodide. Solid-state DSSC with the 1-propargyl-3-methylimidazolium iodide as the single-component solid-state electrolyte has achieved a light-to-electricity power conversion efficiency of 6.3% under illumination of simulated AM1.5G solar light (100 mW cm(-2)), which also exhibits good long-term stability under continuous 1 sun soaking for 1500 h. This finding paves the way for development of high-conductivity single-component solid electrolytes for use in efficient solid-state DSSCs.
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Reduced graphene oxide-TaON composite as a high-performance counter electrode for Co(bpy)3(3+/2+)-mediated dye-sensitized solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 07-24-2013
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We report herein the investigation of TaON nanoparticles incorporating a reduced graphene oxide (RGO) nanocomposite as a counter electrode for application in Co(bpy)3(3+/2+) (bpy = 2,2-bipyridine)-mediated dye-sensitized solar cells (DSSCs). The RGO-TaON nanocomposite has been prepared by mixing graphene oxide (GO) and presynthesized TaON nanoparticles in ethanol/water followed by the facile hydrazine hydrate reduction of GO to RGO. Compared with RGO or TaON alone, the RGO-TaON nanocomposite shows a much higher electrocatalytic activity for the reduction of Co(bpy)3(3+) species owing to synergistic effects, resulting in significantly improved solar-cell performance when it is applied as the counter electrode in DSSCs. An efficiency of 7.65% for the DSSC with the RGO-TaON counter electrode is obtained, competing with the efficiency produced by the Pt counter electrode; additionally, the former exhibits a much better electrochemical stability than the latter in a Co(bpy)3(3+/2+) acetonitrile solution.
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Embedding an electron donor or acceptor into naphtho[2,1-b:3,4-b]dithiophene based organic sensitizers for dye-sensitized solar cells.
Chem. Commun. (Camb.)
PUBLISHED: 07-18-2013
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An electron donor and acceptor, respectively, is embedded into naphtho[2,1-b:3,4-b]dithiophene based organic sensitizers to tune their optoelectronic properties. The DSSC based on FNE52 containing an auxiliary electron acceptor displays a maximum power conversion efficiency of 8.2% and good long-term stability.
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Alterations in the frequency of trinucleotide repeat dynamic mutations in offspring conceived through assisted reproductive technology.
Hum. Reprod.
PUBLISHED: 07-16-2013
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How does the frequency of trinucleotide repeat dynamic mutations in offspring conceived through assisted reproductive technology (ART) compare with the frequency of these mutations in control offspring conceived from spontaneous pregnancies?
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Identification of a mutation in GDF9 as a novel cause of diminished ovarian reserve in young women.
Hum. Reprod.
PUBLISHED: 07-12-2013
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Do any mutations in growth differentiation factor 9 (GDF9) have a role in diminished ovarian reserve (DOR) in young women?
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Water reflection recognition based on motion blur invariant moments in curvelet space.
IEEE Trans Image Process
PUBLISHED: 07-04-2013
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Water reflection, a typical imperfect reflection symmetry problem, plays an important role in image content analysis. Existing techniques of symmetry recognition, however, cannot recognize water reflection images correctly because of the complex and various distortions caused by the water wave. Hence, we propose a novel water reflection recognition technique to solve the problem. First, we construct a novel feature space composed of motion blur invariant moments in low-frequency curvelet space and of curvelet coefficients in high-frequency curvelet space. Second, we propose an efficient algorithm including two sub-algorithms: low-frequency reflection cost minimization and high-frequency curvelet coefficients discrimination to classify water reflection images and to determine the reflection axis. Through experimenting on authentic images in a series of tasks, the proposed techniques prove effective and reliable in classifying water reflection images and detecting the reflection axis, as well as in retrieving images with water reflection.
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Mononuclear lanthanide complexes incorporating an anthracene group: structural modification, slow magnetic relaxation and multicomponent fluorescence emissions in Dy compounds.
Dalton Trans
PUBLISHED: 07-03-2013
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Four mononuclear lanthanide complexes, [Ln(hfac)3(depma)(H2O)] [Ln(III) = Dy (1), Gd (2)], [Dy(hfac)3(depma)2]2·H2O (3) and [Gd(hfac)3(depma)2]·2H2O (4), have been obtained (hfac = hexafluoroacetylacetonate, depma = 9-diethylphosphonomethyl anthracene) by using one (for 1 and 2) or two (for 3 and 4) depma molecules to substitute coordination water molecules of Ln(hfac)3(H2O)2. It was found that the number of introduced depma ligands can modify the coordination geometry of Ln(iii) ions, showing a distorted biscapped triangular prism geometry in isostructural 1 and 2 and a distorted square-antiprismatic geometry in 3 and 4. Magnetic studies reveal that both 1 and 3 show field-induced slow magnetic relaxation under the applied dc field of 1000 Oe. The solid-state fluorescence measurements indicate the presence of multicomponent emissions in 1 and 3, including ligand-centered (LC) emissions from hfac and depma, and yellow emission from Dy(III) ions and only ligand-centered (LC) emissions in 2 and 4.
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RRBS-analyser: a comprehensive web server for reduced representation bisulfite sequencing data analysis.
Hum. Mutat.
PUBLISHED: 06-28-2013
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In reduced representation bisulfite sequencing (RRBS), genomic DNA is digested with the restriction enzyme and then subjected to next-generation sequencing, which enables detection and quantification of DNA methylation at whole-genome scale with low cost. However, the data processing, interpretation, and analysis of the huge amounts of data generated pose a bioinformatics challenge. We developed RRBS-Analyser, a comprehensive genome-scale DNA methylation analysis server based on RRBS data. RRBS-Analyser can assess sequencing quality, generate detailed statistical information, align the bisulfite-treated short reads to reference genome, identify and annotate the methylcytosines (5mCs) and associate them with different genomic features in CG, CHG, and CHH content. RRBS-Analyser supports detection, annotation, and visualization of differentially methylated regions (DMRs) for multiple samples from nine reference organisms. Moreover, RRBS-Analyser provides researchers with detailed annotation of DMR-containing genes, which will greatly aid subsequent studies. The input of RRBS-Analyser can be raw FASTQ reads, generic SAM format, or self-defined format containing individual 5mC sites. RRBS-Analyser can be widely used by researchers wanting to unravel the complexities of DNA methylome in the epigenetic community. RRBS-Analyser is freely available at http://122.228.158.106/RRBSAnalyser/.
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Abnormal expression of miR-301a in gastric cancer associated with progression and poor prognosis.
J Surg Oncol
PUBLISHED: 06-12-2013
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miR-301a is significantly overexpressed in many cancers. However, its expression and biological role in gastric cancer remain poorly understood. We investigated microRNA-301a (miR-301a) expression in gastric cancer and determined its effects on cancer cell behavior and its clinical significance in the development and progression of gastric cancer.
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Potential correlation between statins and pulp chamber calcification.
J Endod
PUBLISHED: 05-24-2013
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3-Hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins) are the first-line pharmaceuticals for the prevention and treatment of dyslipidemia. A recent investigation has shown that statins induced odontoblastic differentiation of dental pulp stem cells. Statins enhance the differentiation of human dental pulp cells by up-regulating mineralization nodules and odontogenic markers. This study tested the hypothesis that the systemic administration of statins results in increased dental pulp calcification.
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Prognostic value and clinical pathology of MACC-1 and c-MET expression in gastric carcinoma.
Pathol. Oncol. Res.
PUBLISHED: 05-02-2013
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This study was to assess the expression of MACC-1 and c-MET in gastric cancer, and to correlate this expression with clinicohistological parameters and patient prognosis. Total RNA was extracted from cancer tissue and adjacent normal mucosa from frozen biopsy specimens of 30 patients with gastric cancer, and MACC-1 expression was assessed by RT-PCR. MACC-1 and c-MET protein expression were also assessed in paraffin-embedded tissues obtained from 436 tumor mucosa and 92 normal mucosa specimens by immunohistochemistry. The correlation between MACC-1 and c-MET expression and clinicopathological factors (age, sex, histology, tumor depth, lymph node status and vessel invasion) were also evaluated. RT-PCR analysis revealed that MACC-1 expression was significantly higher in cancerous mucosa compared with normal tissue. Immunohistochemical analysis indicated that MACC-1 and c-MET were moderately or strongly expressed in gastric cancer tissue, whereas expression was weak or absent in non-cancer tissue. Expression of MACC-1 or c-MET was significantly associated with larger tumor size, deeper tumor invasion, presence of lymph node metastasis, lymphatic involvement, venous invasion, distant metastasis and advanced clinical stage. However, only MACC-1 exhibited significantly greater expression in carcinomas from the higher age group. The intensity of MACC-1 and c-MET expression was also positively correlated. Survival analysis of the 436 gastric cancer patients revealed that patients in clinical stages I, II and III exhibiting lower MACC-1 and c-MET expression had a higher 5-year survival rate compared with patients expressing high levels of these proteins. Multivariate analysis revealed that MACC-1 and c-MET may be independent prognostic indexes of gastric carcinoma (P < 0.01). Our findings confirm that MACC-1 and c-MET expression is strongly related to gastric cancer stage and degree of malignancy, and is inversely correlated to patient prognosis. Thus, MACC-1 and c-MET may interact to promote tumorigenesis and their expression may be used as independent prognostic markers in gastric cancer.
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[Detection and clinicopathologic significance of microsatellite alteration and p53 mutation of neuroendocrine cells in colorectal adenocarcinoma].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 04-25-2013
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To study the possible clonal origin of neuroendocrine cells in colorectal adenocarcinoma.
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Expression of aquaporins in human embryos and potential role of AQP3 and AQP7 in preimplantation mouse embryo development.
Cell. Physiol. Biochem.
PUBLISHED: 04-15-2013
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Water channels, also named aquaporins (AQPs), play crucial roles in cellular water homeostasis.
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Co(II) and Ni(II) complexes based on anthraquinone-1,4,5,8-tetracarboxylic acid (H4AQTC): canted antiferromagnetism and slow magnetization relaxation in {[Co2(AQTC)(H2O)6]·6H2O}.
Dalton Trans
PUBLISHED: 04-12-2013
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Three coordination polymers {[Co2(AQTC)(H2O)6]·6H2O}n (1), {[M2(AQTC)(bpym)(H2O)6]·6H2O}n (M = Co(2), Ni(3)) have been synthesized and structurally characterized, where H4AQTC is anthraquinone-1,4,5,8-tetracarboxylic acid and bpym is 2,2-bipyrimidine. Complex 1 features a 3-D structure, where layers of Co2(AQTC) are cross-linked by Co-H2O chains. Complexes 2 and 3 are isostructural and display 1-D chain structures. The chains are connected through hydrogen-bonding interactions to form 3-D supramolecular structures. Magnetic properties of these complexes are investigated. Compound 1 shows canted antiferromagnetism and slow relaxation below 4.0 K. For complexes 2 and 3, dominant antiferromagnetic interactions are observed. The luminescent properties of the three complexes are investigated as well.
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Charge transfer in cross conjugated 4,8-dithienylbenzo[1,2-b:4,5-b]dithiophene based organic sensitizers.
Chem. Commun. (Camb.)
PUBLISHED: 04-04-2013
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Two novel cross-conjugated isomers based on 4,8-dithienylbenzo[1,2-b:4,5-b]dithiophene have been designed and successfully synthesized. It was found that the charge transfer interaction was much stronger in the benzodithiophene direction as compared with the other perpendicular direction.
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Performance enhancement of dye-sensitized solar cells using an ester-functionalized imidazolium iodide as the solid state electrolyte.
ACS Appl Mater Interfaces
PUBLISHED: 04-02-2013
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Linking an ester group to the imidazolium ring has been demonstrated to improve solar cell performance in terms of short-circuit photocurrent (Jsc), open-circuit photovoltage (Voc), and fill factor (FF) in particular, when the imidazolium iodide mixed with iodine and LiI is used as a solid state electrolyte of dye-sensitized solar cells. Herein, the effect of ester group on solar cell performance has been investigated by means of intensity modulated photocurrent/photovoltage and electrochemical impedance spectroscopy. From the alkyl- to ester-functionalized imidazolium iodide, the increase in Jsc is attributed to the increased charge collection efficiency due to the enhanced conductivity, the increase in Voc is caused by the upward shift of conduction band edge of TiO2, which compensates for the voltage loss arising from the higher charge recombination rate, and the remarkable increase in FF is attributed to the decreased series resistance along with the increased Voc and decreased diode quality factor.
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Enabling interspecies epigenomic comparison with CEpBrowser.
Bioinformatics
PUBLISHED: 03-29-2013
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We developed the Comparative Epigenome Browser (CEpBrowser) to allow the public to perform multi-species epigenomic analysis. The web-based CEpBrowser integrates, manages and visualizes sequencing-based epigenomic datasets. Five key features were developed to maximize the efficiency of interspecies epigenomic comparisons.
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MicroRNAs: new insights into the pathogenesis of endodontic periapical disease.
J Endod
PUBLISHED: 03-27-2013
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Apical periodontitis is an inflammatory disease of the periradicular tissues caused by the hosts immune response to infection of the root canal system. MicroRNAs (miRNAs) have been shown to play an important role in the regulation of inflammation and the immune response; however, their role in the pathogenesis of endodontic periapical disease has not been explored. The purpose of this study was to examine the differential expression of miRNAs in diseased periapical tissues as compared with healthy controls.
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Clonality analysis of neuroendocrine cells in gastric adenocarcinoma.
World J. Gastroenterol.
PUBLISHED: 03-24-2013
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To achieve a better understanding of the origination of neuroendocrine (NE) cells in gastric adenocarcinoma.
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Clinical utility of measuring expression levels of KAP1, TIMP1 and STC2 in peripheral blood of patients with gastric cancer.
World J Surg Oncol
PUBLISHED: 03-09-2013
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We examined preoperative kinesin II-associated protein (KAP1), TIMP metallopeptidase inhibitor 1 (TIMP1) and stanniocalcin 2 (STC2) expression levels in patients with gastric cancers to assess their clinical application for diagnosing and monitoring diseases.
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Aquaporin-1 plays a crucial role in estrogen-induced tubulogenesis of vascular endothelial cells.
J. Clin. Endocrinol. Metab.
PUBLISHED: 02-28-2013
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Aquaporin-1 (AQP1) has been proposed as a mediator of estrogen-induced angiogenesis in human breast cancer and endometrial cancer. Elucidation of the molecular mechanisms governing AQP1-mediated, estrogen-induced angiogenesis may contribute to an improved understanding of tumor development.
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Novel thiazolo[5,4-d]thiazole-based organic dyes for quasi-solid-state dye-sensitized solar cells.
Chem Asian J
PUBLISHED: 02-18-2013
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A series of novel metal-free organic dyes containing the thiazolo[5,4-d]thiazole moiety were designed and synthesized for quasi-solid-state dye-sensitized solar cells (DSSCs). Different alkoxy chains were introduced into the electron donor part of the dye molecules for comparison. The optical, electrochemical, and photovoltaic properties for all sensitizers were systematically investigated. It was found that the sensitizers with the different alkoxy groups have similar photophysical and electrochemical properties, such as absorbance and energy levels, owing to their close chemical structures. However, the quasi-solid-state DSSCs based on the resulting sensitizers exhibit different performance parameters. The quasi-solid-state DSSC based on sensitizer FNE74 with two octyloxy chains possessed the highest solar energy conversion efficiency of 5.10 % under standard AM 1.5G sunlight illumination without the use of coadsorbant agents.
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Comparative RNA-seq analysis reveals potential mechanisms mediating the conversion to androgen independence in an LNCaP progression cell model.
Cancer Lett.
PUBLISHED: 02-13-2013
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The androgen-independent phenotype is an important symptom of refractory prostate cancer. However, the molecular mechanisms underlying this phenotypic conversion remain unclear. Using RNA-seq analysis of androgen-dependent prostate cancer cells (LNCaP) vs. androgen-independent cancer cells (LNCaP-AI-F), we identified 788 differentially expressed genes, 315 alternative splicing events, and eight novel LNCaP-AI-F-specific fusion genes. The fusion genes EIF2AK1-ATR and GLYR1-SLC9A8 were predicted to be damaging and oncogenic. We also observed dramatic changes in androgen receptor (AR)-mediated pathway molecules, including prostate-specific antigen (PSA, a major biomarker of prostate cancer) and AR variants, as well as neuroendocrine-like (NE-like) and tumor stem cell-like characteristics, during androgen-independent phenotype progression. Our findings provide new insights into the regulatory complexities of refractory prostate cancers.
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Membrane-bound RLCKs LIP1 and LIP2 are essential male factors controlling male-female attraction in Arabidopsis.
Curr. Biol.
PUBLISHED: 02-04-2013
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Successful sexual reproduction in animals and plants requires communication between male and female gametes. In flowering plants, unlike in animals, eggs and sperm cells are enclosed in multicellular embryo sacs and pollen grains, respectively; guided growth of the pollen tube into the ovule is necessary for fertilization. Pollen tube guidance requires accurate perception of ovule-emitted guidance cues by the receptors in pollen tubes. Although several ovule-secreted peptides controlling pollen tube guidance have recently been identified, i.e., maize EGG APPARATUS1 (EA1), Torenia LURE1/LURE2, and Arabidopsis CRP810_1/AtLURE1, little is known about the receptors. Here, we identified two receptor-like kinase (RLK) genes preferentially expressed in Arabidopsis pollen tubes, Lost In Pollen tube guidance 1 (LIP1) and 2 (LIP2), which are involved in guidance control of pollen tubes. LIP1 and LIP2 were anchored to the membrane in the pollen tube tip region via palmitoylation, which was essential for their guidance control. Simultaneous inactivation of LIP1 and LIP2 led to impaired pollen tube guidance into micropyle and significantly reduced attraction of pollen tubes toward AtLURE1. Our results suggest that LIP1 and LIP2 represent essential components of the pollen tube receptor complex to perceive the female signal AtLURE1 for micropylar pollen tube guidance.
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What is Visualize?

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

How does it work?

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

Video X seems to be unrelated to Abstract Y...

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.