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Find video protocols related to scientific articles indexed in Pubmed.
[Exendin-4 promotes paracrine action of adipose-derived stem cells through PI3K/Akt signaling pathways].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 10-28-2014
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To investigate the mechanism by which exendin-4 promotes paracrine secretion of cytokines by adipose-derived stem cells (ADSCs).
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Ultrasound Image Edge Detection Based on a Novel Multiplicative Gradient and Canny Operator.
Ultrason Imaging
PUBLISHED: 10-16-2014
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To achieve the fast and accurate segmentation of ultrasound image, a novel edge detection method for speckle noised ultrasound images was proposed, which was based on the traditional Canny and a novel multiplicative gradient operator. The proposed technique combines a new multiplicative gradient operator of non-Newtonian type with the traditional Canny operator to generate the initial edge map, which is subsequently optimized by the following edge tracing step. To verify the proposed method, we compared it with several other edge detection methods that had good robustness to noise, with experiments on the simulated and in vivo medical ultrasound image. Experimental results showed that the proposed algorithm has higher speed for real-time processing, and the edge detection accuracy could be 75% or more. Thus, the proposed method is very suitable for fast and accurate edge detection of medical ultrasound images.
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[Phenolic constituents from Oplopanax horridus].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 10-07-2014
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The chemical constituents were isolated and purified by various chromatographic techniques indluding silica gel, reverse phase silica gel, sephadex LH-20 and pre-HPLC and identified by their physicochemical properties and spectral data. Sixteen phenolic compounds had been isolated and n-butanol extracts which were fractionated from the ethanol extract of Oplopanax horridus roots bark. Their structures were identified as below, including 7 phenylpropanoid compounds, ferulic acid (1), 3-acetylcaffeic acid (2), caffeic acid (3), homovanillyl alcohol 4-O-beta-D-glucopyranoside (4), 3-hydroxyphenethyl alcohol 4-O-beta-D-glucopyranoside (5), 3, 5-dimethoxycinnamyl alcohol 4-O-beta-D-glucopyranoside (6), and 3-dimethoxycinnamyl alcohol 4-O-beta-D-glucopyranoside (7). Three coumarins, scopoletin (8), esculetin (9) and 3'-angeloyl-4'-acetyl-cis-knellactone (10). And 6 lignan compounds, (+)-isolaricires-inol-9'-O-beta-D-glucopyranoside (11), 3, 3'-dimethoxy-4, 9, 9'-trihydroxy-4', 7-epoxy-5', 8-lignan-4, 9-bis-O-beta-D-glucopyranoside (12), (+)-5, 5'-dimethoxylariciresinol 4'-O-beta-D-glucopyranoside (13), (-)-5,5'-dimethoxylariciresinol 4'-O-beta-D-glucopyranoside (14), (-)-pinoresinol 4'-O-beta-D-glucopyranoside (15), and (+)-5, 5'-dimethoxylariciresinol 9'-O-beta-D-glucopyranoside (16). All compounds were isolated and identified for the first time from this plant All the constituents except compounds 4, 6, 12 and 13 were obtained for the first time from the genus Oplopanax.
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Interferons and Their Receptors in Birds: A Comparison of Gene Structure, Phylogenetic Analysis, and Cross Modulation.
Int J Mol Sci
PUBLISHED: 09-29-2014
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Interferon may be thought of as a key, with the interferon receptor as the signal lock: Crosstalk between them maintains their balance during viral infection. In this review, the protein structure of avian interferon and the interferon receptor are discussed, indicating remarkable similarity between different species. However, the structures of the interferon receptors are more sophisticated than those of the interferons, suggesting that the interferon receptor is a more complicated signal lock system and has considerable diversity in subtypes or structures. Preliminary evolutionary analysis showed that the subunits of the interferon receptor formed a distinct clade, and the orthologs may be derived from the same ancestor. Furthermore, the development of interferons and interferon receptors in birds may be related to an animal's age and the maintenance of a balanced state. In addition, the equilibrium between interferon and its receptor during pathological and physiological states revealed that the virus and the host influence this equilibrium. Birds could represent an important model for studies on interferon's antiviral activities and may provide the basis for new antiviral strategies.
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Effect of CYP2C9-VKORC1 interaction on warfarin stable dosage and its predictive algorithm.
J Clin Pharmacol
PUBLISHED: 09-04-2014
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This study aimed to identify the effect of CYP2C9-VKORC1 interaction on warfarin dosage requirement and its predictive algorithm by investigating four populations. Generalized linear model was used to evaluate the relationship between the interaction and warfarin stable dosage (WSD), whereas multiple linear regression analysis was applied to construct the WSD predictive algorithm. To evaluate the effect of CYP2C9-VKORC1 interaction on the predictive algorithms, we compared the algorithms with and without the interaction. The interaction was significantly associated with WSD in the Chinese and White cohorts (P values?
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New organic donor-acceptor-?-acceptor sensitizers for efficient dye-sensitized solar cells and photocatalytic hydrogen evolution under visible-light irradiation.
ChemSusChem
PUBLISHED: 08-25-2014
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Two organic donor-acceptor-?-acceptor (D-A-?-A) sensitizers (AQ and AP), containing quinoxaline/pyrido[3,4-b]pyrazine as the auxiliary acceptor, have been. Through fine-tuning of the auxiliary acceptor, a higher designed and synthesized photoelectric conversion efficiency of 6.02% for the AQ-based dye-sensitized solar cells under standard global AM1.5 solar conditions was achieved. Also, it was found that AQ-Pt/TiO2 photocatalysts displayed a better rate of H2 evolution under visible-light irradiation (420 nm
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Evaluation of miR-720 prognostic significance in patients with colorectal cancer.
Tumour Biol.
PUBLISHED: 08-24-2014
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Aberrant expression of miR-720 had been reported in several cancers. However, the expression level and prognostic value of miR-720 in colorectal cancer (CRC) had not been addressed. In our study, we detected the expression level of miR-720 in 96 CRC tissues to evaluate its clinicopathological characteristics in colorectal cancer. Kaplan-Meier survival curve was performed to evaluate the prognostic role of miR-720 in patients with CRC. Furthermore, in vitro, we transfected the miR-720 mimics or inhibitors into the corresponding CRC cell lines and evaluated the effects on the abilities of cell growth, colony formation, migration, wound healing, and invasion in CRC cells. Our data showed that miR-720 level was significantly upregulated in CRC tissues than that in corresponding normal-appearing tissues (NATs) (p?
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NF-?B (p65) negatively regulates myocardin-induced cardiomyocyte hypertrophy through multiple mechanisms.
Cell. Signal.
PUBLISHED: 08-23-2014
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Myocardin is well known to play a key role in the development of cardiomyocyte hypertrophy. But the exact molecular mechanism regulating myocardin stability and transactivity to affect cardiomyocyte hypertrophy has not been studied clearly. We now report that NF-?B (p65) can inhibit myocardin-induced cardiomyocyte hypertrophy. Then we explore the molecular mechanism of this response. First, we show that p65 can functionally repress myocardin transcriptional activity and also reduce the protein expression of myocardin. Second, the function of myocardin can be regulated by epigenetic modifications. Myocardin sumoylation is known to transactivate cardiac genes, but whether p65 can inhibit SUMO modification of myocardin is still not clear. Our data show that p65 weakens myocardin transcriptional activity through attenuating SUMO modification of myocardin by SUMO1/PIAS1, thereby impairing myocardin-mediated cardiomyocyte hypertrophy. Furthermore, the expression of myocardin can be regulated by several microRNAs, which play important roles in the development and function of the heart and muscle. We next investigated potential role of miR-1 in cardiac hypotrophy. Our results show that p65 can upregulate the level of miR-1 and miR-1 can decrease protein expression of myocardin in cardiac myocytes. Notably, miR-1 expression is also controlled by myocardin, leading to a feedback loop. These data thus provide important and novel insights into the function that p65 inhibits myocardin-mediated cardiomyocyte hypertrophy by downregulating the expression and SUMO modification of myocardin and enhancing the expression of miR-1.
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Decreased BMP2 signal in GIT1 knockout mice slows bone healing.
Mol. Cell. Biochem.
PUBLISHED: 08-20-2014
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Endochondral ossification, an important stage of fracture healing, is regulated by a variety of signaling pathways. Transforming growth factor ? (TGF?) superfamily plays important roles and comprises TGF?s, bone morphogenetic proteins (BMPs), and growth differentiation factors. TGF?s primarily regulate cartilage formation and endochondral ossification. BMP2 shows diverse efficacy, from the formation of skeleton and extraskeletal organs to the osteogenesis and remodeling of bone. G-protein-coupled receptor kinase 2-interacting protein-1 (GIT1), a shuttle protein in osteoblasts, facilitates fracture healing by promoting bone formation and increasing the secretion of vascular endothelial growth factor. Our study examined whether GIT1 regulates fracture healing through the BMP2 signaling pathway and/or through the TGF? signaling pathway. GIT1 knockout (KO) mice exhibited delayed fracture healing, chondrocyte accumulation in the fracture area, and reduced staining intensity of phosphorylated Smad1/5/8 (pSmad1/5/8) and Runx2. Endochondral mineralization diminished while the staining intensity of phosphorylated Smad2/3 (pSmad2/3) showed no significant change. Bone marrow mesenchymal stem cells extracted from GIT1 KO mice showed a decline of pSmad1/5/8 levels and of pSmad1/5/8 translocated into the cell nucleus after BMP2 stimulus. We detected no significant change in the pSmad2/3 level after TGF?1 stimulus. Data obtained from reporter gene analysis of C3H10T1/2 cells cultured in vitro confirmed these findings. GIT1-siRNA inhibited transcription in the cell nucleus via pSmad1/5/8 after BMP2 stimulus but had no significant effect on transcription via pSmad2/3 after TGF?1 stimulus. Our results indicate that GIT1 regulates Smad1/5/8 phosphorylation and mediates BMP2 regulation of Runx2 expression, thus affecting endochondral ossification at the fracture site.
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Anti-fibrosis effect of scutellarin via inhibition of endothelial-mesenchymal transition on isoprenaline-induced myocardial fibrosis in rats.
Molecules
PUBLISHED: 07-22-2014
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Scutellarin (SCU) is the major active component of breviscapine and has been reported to be capable of decreasing myocardial fibrosis. The aim of the present study is to investigate whether SCU treatment attenuates isoprenaline-induced myocardial fibrosis and the mechanisms of its action. Rats were injected subcutaneously with isoprenaline (Iso) to induce myocardial fibrosis and rats in the SCU treatment groups were intraperitoneally infused with SCU (10 mg·kg-1·d-1 or 20 mg·kg-1·d-1, for 14 days). Post-treatment, cardiac functional measurements and the left and right ventricular weight indices (LVWI and RVWI, respectively) were analysed. Pathological alteration, expression of type I and III collagen, Von Willebrand factor, ?-smooth muscle actin, cluster of differentiation-31 (CD31), and the Notch signalling proteins (Notch1, Jagged1 and Hes1) were examined. The administration of SCU resulted in a significant improvement in cardiac function and decrease in the cardiac weight indices; reduced fibrous tissue proliferation; reduced levels of type I and III collagen; increased microvascular density; and decreased expression of ?-smooth muscle actin and increased expression of CD31, Notch1, Jagged1 and Hes1 in isoprenaline-induced myocardial fibrosis in rats. Our results suggest that SCU prevents isoprenaline-induced myocardial fibrosis via inhibition of cardiac endothelial-mesenchymal transition potentially, which may be associated with the Notch pathway.
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IKK? negatively regulates ASC-dependent inflammasome activation.
Nat Commun
PUBLISHED: 07-17-2014
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The inflammasomes are multiprotein complexes that activate caspase-1 in response to infections and stress, resulting in the secretion of pro-inflammatory cytokines. Here we report that I?B kinase ? (IKK?) is a critical negative regulator of apoptosis-associated specklike protein containing a C-terminal caspase-activation-andrecruitment (CARD) domain (ASC)-dependent inflammasomes. IKK? controls the inflammasome at the level of the adaptor ASC, which interacts with IKK? in the nucleus of resting macrophages in an IKK? kinase-dependent manner. Loss of IKK? kinase activity results in inflammasome hyperactivation. Mechanistically, the downstream nuclear effector IKK-related kinase (IKKi) facilitates translocation of ASC from the nucleus to the perinuclear area during inflammasome activation. ASC remains under the control of IKK? in the perinuclear area following translocation of the ASC/IKK? complex. Signal 2 of NLRP3 activation leads to inhibition of IKK? kinase activity through the recruitment of PP2A, allowing ASC to participate in NLRP3 inflammasome assembly. Taken together, these findings reveal a IKKi-IKK?-ASC axis that serves as a common regulatory mechanism for ASC-dependent inflammasomes.
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SAHA inhibits the transcription initiation of HPV18 E6/E7 genes in HeLa cervical cancer cells.
Gene
PUBLISHED: 07-14-2014
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High risk human papillomavirus (HPV) is a well recognized causative agent of cervical cancer. Suberoylanilide hydroxamic acid (SAHA) is a potential anti-cervical cancer drug; however, its effect on the expression of HPV E6 and E7 genes remains unclear. Here, we show that, in SAHA treated HeLa cells, HPV18 E6 and E7 mRNA and protein levels were reduced, HPV18 promoter activity was decreased, and the association of RNP II with HPV18 promoter was diminished, suggesting that SAHA inhibited the transcription initiation of HPV18 E6 and E7 genes. In SAHA-treated HeLa, although the level of lysine 9-acetylated histone H3 in the whole cell extracts increased obviously, its enrichment on HPV18 promoter was significantly reduced which is correlated with the down-regulation of HPV E6 and E7.
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Inhibition of EZH2 expression is associated with the proliferation, apoptosis, and migration of SW620 colorectal cancer cells in vitro.
Exp. Biol. Med. (Maywood)
PUBLISHED: 07-10-2014
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Epigenetic changes have been recently recognized as important in human cancers. Enhancer of zeste homologue 2 gene (EZH2) has been shown the overexpression in various human cancers, consistent with a straightforward role of EZH2 as an oncogene, but its function in carcinogenesis is partly contradictory. The role of EZH2 in development of human colorectal cancer (CRC) has not yet been clarified. In the present study, elevated expression of EZH2 is observed in CRC tissues by immunohistochemical staining, compared with the paired nontumor tissues. The expression of EZH2 in CRC cell lines is consistent with the trend in cancer tissues using reverse transcription polymerase chain reaction (RT-PCR). We show that EZH2 expression levels are significantly correlated with tumor-lymph node-metastasis stage and lymph node metastasis in CRC patients. EZH2 level of transcription and protein is inhibited by small interfering RNA (siRNA). More importantly, EZH2-siRNA inhibits the proliferation and migration of SW620 cells while promoting their apoptosis, and inducing G0/G1 cell cycle arrest of SW620 cells. Collectively, our results suggest that elevated EZH2 level might contribute to the development of CRC. A better understanding of epigenetic mechanisms and the relevance of EZH2 in the progression of CRC will help to identify a novel strategy for potential target in CRC therapy.
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Concept and simulation study of a novel localization method for robotic endoscopic capsules using multiple positron emission markers.
Med Phys
PUBLISHED: 07-04-2014
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Over the last decade, wireless capsule endoscope has been the tool of choice for noninvasive inspection of the gastrointestinal tract, especially in the small intestine. However, the latest clinical products have not been equipped with a sufficiently accurate localization system which makes it difficult to determine the location of intestinal abnormalities, and to apply follow-up interventions such as biopsy or drug delivery. In this paper, the authors present a novel localization method based on tracking three positron emission markers embedded inside an endoscopic capsule.
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Evolution of the BBAA component of bread wheat during its history at the allohexaploid level.
Plant Cell
PUBLISHED: 07-02-2014
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Subgenome integrity in bread wheat (Triticum aestivum; BBAADD) makes possible the extraction of its BBAA component to restitute a novel plant type. The availability of such a ploidy-reversed wheat (extracted tetraploid wheat [ETW]) provides a unique opportunity to address whether and to what extent the BBAA component of bread wheat has been modified in phenotype, karyotype, and gene expression during its evolutionary history at the allohexaploid level. We report here that ETW was anomalous in multiple phenotypic traits but maintained a stable karyotype. Microarray-based transcriptome profiling identified a large number of differentially expressed genes between ETW and natural tetraploid wheat (Triticum turgidum), and the ETW-downregulated genes were enriched for distinct Gene Ontology categories. Quantitative RT-PCR analysis showed that gene expression differences between ETW and a set of diverse durum wheat (T. turgidum subsp durum) cultivars were distinct from those characterizing tetraploid cultivars per se. Pyrosequencing revealed that the expression alterations may occur to either only one or both of the B and A homoeolog transcripts in ETW. A majority of the genes showed additive expression in a resynthesized allohexaploid wheat. Analysis of a synthetic allohexaploid wheat and diverse bread wheat cultivars revealed the rapid occurrence of expression changes to the BBAA subgenomes subsequent to allohexaploidization and their evolutionary persistence.
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[Oleanolic acid synergizes with cyclosporine A to prolong renal allograft survival in rats].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 06-28-2014
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To investigate the synergistic effect of oleanolic acid (OA) and cyclosporine A (CsA) on the survival of renal allografts in rats.
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A new C??-diterpenoid alkaloid from the roots of Aconitum duclouxii.
Nat. Prod. Res.
PUBLISHED: 06-20-2014
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A new C??-diterpenoid alkaloid, ducloudine F (1), was obtained from the roots of Aconitum duclouxii, along with eight known alkaloids (2-9) isolated from this species for the first time. Their structures were established on the basis of extensive spectroscopic analyses. The antimicrobial activities of these compounds were investigated.
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Work stress, work motivation and their effects on job satisfaction in community health workers: a cross-sectional survey in China.
BMJ Open
PUBLISHED: 06-07-2014
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It is well documented that both work stress and work motivation are key determinants of job satisfaction. The aim of this study was to examine levels of work stress and motivation and their contribution to job satisfaction among community health workers in Heilongjiang Province, China.
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Self-assembling choline mimicks with enhanced binding affinities to C-LytA protein.
Sci Rep
PUBLISHED: 06-03-2014
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Streptococcus pneumoniae (pneumococcus) causes multiple illnesses in humans. Exploration of effective inhibitors with multivalent attachment sites for choline-binding modules is of great importance to reduce the pneumococcal virulence. In this work, we successfully developed two self-assembling choline mimicks, Ada-GFFYKKK' and Nap-GFFYKKK', which have the abilities to self-assemble into nanoparticles and nanofibers, respectively, yielding multivalent architectures. Additionally, the best characterized choline-binding module, C-terminal moiety of the pneumococcal cell-wall amidase LytA (C-LytA) was also produced with high purity. The self-assembling Ada-GFFYKKK' and Nap-GFFYKKK' show strong interactions with C-LytA, which possess much higher association constant values to the choline-binding modules as compared to the individual peptide Fmoc-K'. This study thus provides a self-assembly approach to yield inhibitors that are very promising for reducing the pneumococcal virulence.
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Relationships between actual and desired workplace characteristics and job satisfaction for community health workers in China: a cross-sectional study.
BMC Fam Pract
PUBLISHED: 05-27-2014
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BackgroundCommunity health workers are the main providers of community health services in China and have been important in the process of health system reform that has been in place since 2009. Therefore, it is critical that healthcare managers and policy decision makers motivate current staff and improve their job satisfaction. This study examined workplace characteristics and their contribution to job satisfaction in community health workers in Heilongjiang Province, China.MethodsA cross-sectional survey of 448 community health workers, from three cities in Heilongjiang province, was conducted between October 1, 2012 and December 31, 2012. Multistage sampling procedures were used to measure socioeconomic and demographic status, job satisfaction, and both actual and desired workplace characteristics. Factor analysis was conducted to determine the main factors contributing to workplace characteristics, and multiple linear regression analysis was performed to assess the key determinants of job satisfaction.ResultsEight groups of factors were identified as the most important workplace characteristics. These comprised system and policy; fringe benefits; work itself; work relationships; professional development; recognition; work environment; and remuneration. In all cases, all desired workplace characteristics were higher than the associated actual workplace characteristics. The main determinants of job satisfaction were occupation, years worked in health service institution, and five subscales representing the gap between desired and actual workplace characteristics, which were system and policy; fringe benefits; working relationship; professional development; and remuneration.ConclusionsThese findings suggested that managers wishing to enhance job satisfaction should assess workplace characteristics comprehensively and design mechanisms that reduce the gap between actual and desired workplace characteristics.
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New insights into electrocatalysis based on plasmon resonance for the real-time monitoring of catalytic events on single gold nanorods.
Anal. Chem.
PUBLISHED: 05-12-2014
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Gold nanoparticles (GNPs) have been widely applied in industrial catalysis and electrocatalysis. Owing to their wide variety of shapes, sizes, and compositions, a range of different catalytic properties is possible. Thus, it is important to monitor catalytic processes and their mechanisms on single GNP surfaces to avoid averaging effects in bulk systems. Therefore, a novel method based on dark-field scattering spectroscopy was developed to monitor, in real-time, the electrocatalytic oxidation of hydrogen peroxide on a single gold nanoparticle surface. The catalytic mechanism was revealed via the plasmon resonance scattering spectral shift of single gold nanorod with the elimination of bulk effect. Moreover, we found that the presence of chloride ions could block the catalytic activity of nanorods for the oxidation of H2O2. Most importantly, it was discovered that individual nanoparticles have variable properties with different spectra shifts during the catalytic process. The obtained optical signals from individual nanorods not only offer versatile information regarding the reaction but also improve the understanding of electrochemistry and the catalysis mechanism of single nanoparticles.
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A novel toxicity mechanism of CdSe nanoparticles to Saccharomyces cerevisiae: Enhancement of vacuolar membrane permeabilization (VMP).
Chem. Biol. Interact.
PUBLISHED: 05-01-2014
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Cadmium selenide (CdSe) nanoparticles are implemented in a wide range of applications, but their potential risk to the ecosystem, especially to the organisms essential for the maintenance of ecosystem homeostasis, such as fungal populations, plants and bacteria, remains to be elucidated. In this study, we investigated their toxicity to one of the most important fungal model organisms, Saccharomyces cerevisiae. Growth inhibition assays revealed that the synthesized CdSe nanoparticles with the sizes of 20-30nm had strong inhibitory effect on yeast growth (IC50=80ppm). This toxicity was not attributed to mitochondrial dysfunction and autophagy, but was dependent on End3-mediated endocytosis, and was associated with reactive oxygen species (ROS) accumulation and an enhancement of vacuolar membrane permeabilization (VMP). These results reveal a key role of the vacuole during the interaction between CdSe nanoparticles and yeast cells.
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[Health survey of painting and coating workers in an automobile manufacturing enterprise in Guangzhou, China].
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
PUBLISHED: 04-24-2014
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To investigate the health status of painting and coating workers in an automobile manufacturing enterprise in Guangzhou, China and analyze the influential factors for the health status of these workers, and to provide health intervention measures and strategies.
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Rational design of multifunctional hetero-hexameric proteins for hydrogel formation and controlled delivery of bioactive molecules.
Adv Healthc Mater
PUBLISHED: 04-22-2014
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A hetero-hexameric protein system is developed in this study, which not only functions as cross-linkers for hydrogel formation but also offers docking sites for controlled delivery of bioactive molecules. First, a hexameric protein with two, four, and six tax-interacting protein-1 (TIP-1), respectively (named as 2T, 4T, and 6T), is designed and obtained. As the hexapeptide ligand (WRESAI) can specifically bind to TIP-1 with high affinity, the hexameric proteins of 2T, 4T, and 6T can be used to crosslink the self-assembling nanofibers of Nap-GFFYGGGWRESAI, leading to formation of injectable biohybrid hydrogels with tunable mechanical properties. Furthermore, a hetero-hexameric protein containing four TIP-1 and two C-terminal moiety of the pneumococcal cell-wall amidase LytA (C-LytA) proteins is designed and engineered (named as 4T2C). The 4T2C proteins can not only serve as cross-linkers for hydrogel formation but also provide docking sites for loading and controlled release of model drug Rhoda-GGK'. This study opens up new opportunities for further development of multifunctional hetero- recombinant protein-based hydrogels for biological applications.
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MyD88-dependent interplay between myeloid and endothelial cells in the initiation and progression of obesity-associated inflammatory diseases.
J. Exp. Med.
PUBLISHED: 04-21-2014
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Low-grade systemic inflammation is often associated with metabolic syndrome, which plays a critical role in the development of the obesity-associated inflammatory diseases, including insulin resistance and atherosclerosis. Here, we investigate how Toll-like receptor-MyD88 signaling in myeloid and endothelial cells coordinately participates in the initiation and progression of high fat diet-induced systemic inflammation and metabolic inflammatory diseases. MyD88 deficiency in myeloid cells inhibits macrophage recruitment to adipose tissue and their switch to an M1-like phenotype. This is accompanied by substantially reduced diet-induced systemic inflammation, insulin resistance, and atherosclerosis. MyD88 deficiency in endothelial cells results in a moderate reduction in diet-induced adipose macrophage infiltration and M1 polarization, selective insulin sensitivity in adipose tissue, and amelioration of spontaneous atherosclerosis. Both in vivo and ex vivo studies suggest that MyD88-dependent GM-CSF production from the endothelial cells might play a critical role in the initiation of obesity-associated inflammation and development of atherosclerosis by priming the monocytes in the adipose and arterial tissues to differentiate into M1-like inflammatory macrophages. Collectively, these results implicate a critical MyD88-dependent interplay between myeloid and endothelial cells in the initiation and progression of obesity-associated inflammatory diseases.
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The Effects of Lycopene on the Methylation of the GSTP1 Promoter and Global Methylation in Prostatic Cancer Cell Lines PC3 and LNCaP.
Int J Endocrinol
PUBLISHED: 03-28-2014
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DNA (cytosine-5-) methylation silencing of GSTP1 function occurs in prostate adenocarcinoma (PCa). Previous studies have shown that there is an inverse relationship between dietary lycopene intake and the risk of PCa. However, it is unknown whether lycopene reactivates the tumor suppressor gene glutathioneS-transferase-? (GSTP1) by demethylation of the hypermethylated CpGs that act to silence the GSTP1 promoter. Here, we demonstrated that lycopene treatment significantly decreased the methylation levels of the GSTP1 promoter and increased the mRNA and protein levels of GSTP1 in an androgen-independent PC-3 cell line. In contrast, lycopene treatment did not demethylate the GSTP1 promoter or increase GSTP1 expression in the androgen-dependent LNCaP cell line. DNA methyltransferase (DNMT) 3A protein levels were downregulated in PC-3 cells following lycopene treatment; however, DNMT1 and DNMT3B levels were unchanged. Furthermore, the long interspersed element (LINE-1) and short interspersed element ALU were not demethylated when treated by lycopene. In LNCaP cells, lycopene treatment did not affect any detected DNMT protein expression, and the methylation levels of LINE-1 and ALU were decreased. These results indicated that the protective effect of lycopene on the prostate is different between androgen-dependent and androgen-independent derived PCa cells. Further, in vivo studies should be conducted to confirm these promising results and to evaluate the potential role of lycopene in the protection of the prostate.
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A strong adsorbent for Cu²?: graphene oxide modified with triethanolamine.
Dalton Trans
PUBLISHED: 03-27-2014
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A strong adsorbent TEA-GO for Cu(2+) is prepared using TEA modified GO nanosheets. FT-IR and XPS results show that epoxy groups on GO are eliminated, and simultaneously hydroxyl groups and C-N dominate the surface groups of TEA-GO. The increased equilibrium capacity of TEA-GO for a high initial concentration of Cu(2+) makes it a promising adsorbent for heavy metal ions.
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Medelamine C, a new omega-hydroxy alkylamine derivative from endophytic Streptomyces sp. YIM 66142.
Nat Prod Commun
PUBLISHED: 03-26-2014
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A new alkylamine derivative and a common fatty acid were isolated from Streptomyces sp. YIM 66142. On the basis of spectral data, including HRMS, NMR and 2D NMR, their structures were determined as medelamine C (1) and isomyristic acid (2). The omega-hydroxyl group in structure 1 is rare in a natural alkylamine. The possible biosynthetic pathway in the genus Streptomyces from isomyristic acid (2) to medelamines is proposed. Compound 1 showed no obvious cytotoxicity against HL-60, SMMC-7721, A-549, MCF-7, SW480 cell lines. The omega-hydroxyl and the acetyl at NH in compound 1 decreased its cytotoxicity in comparison with that of medelamine.
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Magnetic field tunable small-scale mechanical properties of nickel single crystals measured by nanoindentation technique.
Sci Rep
PUBLISHED: 03-19-2014
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Nano- and micromagnetic materials have been extensively employed in micro-functional devices. However, measuring small-scale mechanical and magnetomechanical properties is challenging, which restricts the design of new products and the performance of smart devices. A new magnetomechanical nanoindentation technique is developed and tested on a nickel single crystal in the absence and presence of a saturated magnetic field. Small-scale parameters such as Young's modulus, indentation hardness, and plastic index are dependent on the applied magnetic field, which differ greatly from their macroscale counterparts. Possible mechanisms that induced 31% increase in modulus and 7% reduction in hardness (i.e., the flexomagnetic effect and the interaction between dislocations and magnetic field, respectively) are analyzed and discussed. Results could be useful in the microminiaturization of applications, such as tunable mechanical resonators and magnetic field sensors.
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[Investigation of occupational noise exposure and hearing loss in large automobile manufacturing enterprise during 2006-2010 in Guangzhou, China].
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
PUBLISHED: 03-18-2014
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To analyze the relationship between occupational noise exposure and hearing loss among workers in large automobile manufacturing enterprise during 2006-2010 in Guangzhou, China.
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Synthesis and properties of a lacquer wax-based quarternary ammonium gemini surfactant.
Molecules
PUBLISHED: 03-11-2014
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Lacquer wax is an important fatty resource obtained from the mesocarp of the berries of Toxicodendron vernicifluum. In order to expand the applications of lacquer wax, we hydrolyzed it after establishing the best conditions for the acid-catalyzed hydrolysis using a Box-Behnken design. Then we synthesized a quarternary ammonium gemini surfactant by a three-step reaction. The surface properties of an aqueous solution of the final product were investigated. The optimum conditions were 9% catalyst, 100 °C of reaction temperature and 14 h of reaction time, while the maximum free fatty acids (FFA)% was 99.67%. From the gas chromatography, the main fatty acids of the lacquer wax were palmitic, oleic and octadecanoic acid. The lacquer wax gemini surfactant was synthesized, and its structure was confirmed by IR and NMR. The experiments showed that the critical micelle concentration (CMC) is 5 × 10?? mol·L?¹, the surface tension is 33.6 mN·m?¹. When the content of surfactant was 0.1%, the separation time of 5 mL water was 10 min.
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Seasonal succession of phytoplankton community and its relationship with environmental factors of North Temperate Zone water of the Zhalong Wetland, in China.
Ecotoxicology
PUBLISHED: 03-07-2014
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A data set of phytoplankton community and environmental parameters in a hydrological integrity period, i.e. a poor water term, a medium term and a rich water term of North Temperate Zone climate, was analyzed in order to describe seasonal variation of phytoplankton community and its relationship with environmental variables in the Zhalong Wetland of China. The algal population of the Zhalong Wetland was not abundant, with a mean density of 5.08 × 10(7) cell/L (ranged from 4.54 × 10(7) cell/L in a poor term to 5.56 × 10(7) cell/L a medium term). However, its diversity was essentially limited to Cryptophyta, Bacillariophyta, Chlorophyta, Euglenophyta being the group with highest densities. There were considerable seasonal variations in phytoplankton composition. In general, the dominance of Bacillariophyceae was found in a medium term, which was higher than the other period (p < 0.05). The rich water period also showed Bacillariophyceae and Chlorophyta dominance while the phytoplankton was dominated by Cryptophyta erosa in a poor water term. 10 environmental variables, which were significant (p < 0.05) during the studied periods in one-way analysis of covariance, were selected to explore the relationship between phytoplankton structure and environmental factors by canonical correspondence analysis (CCA). The results of the CCA applied to the environmental factors indicated that water temperature (WT) and ammonia (NH3-N) significantly influenced the phytoplankton community (p < 0.05; Monte Carlo test of first constrained axis). Besides WT and NH3-N, the most discriminate physic-chemical variables were nitrite (NO2-N), suspend solid, nitrate (NO3-N), silicon dioxide (SiO2) and all the 10 physical-chemical parameters had a higher marginal effect and ?A in the series of constrained CCAs though they were not significant.
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IRAK4 dimerization and trans-autophosphorylation are induced by Myddosome assembly.
Mol. Cell
PUBLISHED: 03-03-2014
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Trans-autophosphorylation is among the most prevalent means of protein kinase activation, yet its molecular basis is poorly defined. In Toll-like receptor and interleukin-1 receptor signaling pathways, the kinase IRAK4 is recruited to the membrane-proximal adaptor MyD88 through death domain (DD) interactions, forming the oligomeric Myddosome and mediating NF-?B activation. Here we show that unphosphorylated IRAK4 dimerizes in solution with a KD of 2.5 ?M and that Myddosome assembly greatly enhances IRAK4 kinase domain (KD) autophosphorylation at sub-KD concentrations. The crystal structure of the unphosphorylated IRAK4(KD) dimer captures a conformation that appears to represent the actual trans-autophosphorylation reaction, with the activation loop phosphosite of one IRAK4 monomer precisely positioned for phosphotransfer by its partner. We show that dimerization is crucial for IRAK4 autophosphorylation in vitro and ligand-dependent signaling in cells. These studies identify a mechanism for oligomerization-driven allosteric autoactivation of IRAK4 that may be general to other kinases activated by autophosphorylation.
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Expression of Lgr5, a marker of intestinal stem cells, in colorectal cancer and its clinicopathological significance.
Biomed. Pharmacother.
PUBLISHED: 02-27-2014
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Cancer stem cells (CSCs) have been the focus of intense investigations in cancer research although the cellular origin of CSCs has not been clearly determined. Lgr5 is a regulated target of Wnt/?-catenin signaling, which was first identified as a marker of intestinal stem cells. However, the expression of Lgr5 in human colorectal cancer (CRC) and its clinical clinicopathological significance in CRC patients as well as its correlation with Wnt/?-catenin pathway are not fully explored. Localization and expression of Lgr5 in CRC tissues was performed by immunohistochemical staining. The correlation between its expression levels and clinicopathological features as well as clinical outcomes of patients was analysed. The quantitative expression levels of Lgr5 in various CRC cell lines were determined using real-time RT-PCR. The relationship between Lgr5 expression and Wnt/?-catenin pathway in CRC was also investigated. Obviously elevated expression of Lgr5 was observed in CRC tissues, compared to the paired nontumor tissues. mRNA expression levels of Lgr5 was positively correlated with the expression of ?-catenin in CRC tissues. The expression of Lgr5 was various in different CRC cell lines. Low and high expression levels of Lgr5 were significantly correlated with clinicopathological features such as TNM stage, lymph node metastasis and vascular invasion of CRC patients. More importantly, Lgr5 expression in CRC tissues was also associated with tumor angiogenesis as well as clinical outcomes. Taken together, these results suggest that elevated Lgr5 expression might contribute to the development and progression of CRC, and it could also be used a potential unfavorable prognostic biomarker for CRC. A better understanding of molecule mechanisms and the relevance of potential value for Lgr5 in the progression of CRC will help to identify a novel therapeutic strategy for CRC patients.
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On the mechanisms of the recurvature of super typhoon Megi.
Sci Rep
PUBLISHED: 02-19-2014
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Tropical cyclones (TC) are one of the most threatening natural hazards to human beings. Although significant improvements have been made in the track prediction of TCs during the past several decades, considerable uncertainties still exist, especially for recurving tracks. In this study, we explore the physical mechanisms that drove the large recurvature of super typhoon Megi through numerical sensitivity experiments using a regional atmospheric model. The results indicate that the cold air intrusion from the northwest to the southeast of China is the main cause of the sharp turning of Megi. This finding suggests that a cold air intrusion could be taken as an indicator for predicting the recurvature of a tropical cyclone in the future.
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Re-expression and epigenetic modification of maspin induced apoptosis in MCF-7 cells mediated by myocardin.
Cell. Signal.
PUBLISHED: 02-16-2014
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Breast cancer is the leading cause of cancer death in women worldwide. It is well known that oncogene activation and anti-oncogene inactivation affect the development and progression of breast cancer, but the role of oncogene activation and anti-oncogene inactivation in breast cancer is still not fully understood. We now report that maspin acts as a tumor suppressor gene to induce MCF-7 cell apoptosis. In addition, maspin promoter hypermethylation and histone hypoacetylation lead to silencing of maspin gene expression in MCF-7 cells. Moreover, DNA methyltransferase (DNMT) inhibitor 5-aza-2'-deoxycytidine (5-aza-dc) and/or the histone deacetylase (HDAC) inhibitor Trichostatin A (TSA) strongly up-regulated the expression of maspin in MCF-7 cells. Notably, myocardin can promote the re-expression of maspin in MCF-7 cells. Luciferase assay shows that myocardin activates the transcription of maspin promoter by CArG box. More importantly, 5-aza-dc/TSA and myocardin synergetically enhance re-expression of maspin and augment maspin-mediated apoptosis in MCF-7 cells. Thus, these data reveal the new insight that myocardin meditates apoptosis in breast cancer through affecting maspin re-expression and epigenetic modification to regulate the development of breast cancer, thereby raising the possibility of its use in breast cancer therapy.
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Experimental investigation into biomechanical and biotribological properties of a real intestine and their significance for design of a spiral-type robotic capsule.
Proc Inst Mech Eng H
PUBLISHED: 02-11-2014
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This article reports on the results and implications of our experimental investigation into the biomechanical and biotribological properties of a real intestine for the optimal design of a spiral-type robotic capsule. Dynamic shear experiments were conducted to evaluate how the storage and loss moduli and damping factor of the small intestine change with the speed or the angular frequency. The sliding friction between differently shaped test pieces, with a topology similar to that of the spirals, and the intestine sample was experimentally determined. Our findings demonstrate that the intestine's biomechanical and biotribological properties are coupled, suggesting that the sliding friction is strongly related to the internal friction of the intestinal tissue. The significant implication of this finding is that one can predict the reaction force between the capsule with a spiral-type traction topology and the intestine directly from the intestine's biomechanical measurements rather than employing complicated three-dimensional finite element analysis or an inaccurate analytical model. Sliding friction experiments were also conducted with bar-shaped solid samples to determine the sliding friction between the samples and the small intestine. This sliding friction data will be useful in determining spiral material for an optimally designed robotic capsule.
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Single-molecule force spectroscopy reveals force-enhanced binding of calcium ions by gelsolin.
Nat Commun
PUBLISHED: 02-10-2014
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Force is increasingly recognized as an important element in controlling biological processes. Forces can deform native protein conformations leading to protein-specific effects. Protein-protein binding affinities may be decreased, or novel protein-protein interaction sites may be revealed, on mechanically stressing one or more components. Here we demonstrate that the calcium-binding affinity of the sixth domain of the actin-binding protein gelsolin (G6) can be enhanced by mechanical force. Our kinetic model suggests that the calcium-binding affinity of G6 increases exponentially with force, up to the point of G6 unfolding. This implies that gelsolin may be activated at lower calcium ion levels when subjected to tensile forces. The demonstration that cation-protein binding affinities can be force-dependent provides a new understanding of the complex behaviour of cation-regulated proteins in stressful cellular environments, such as those found in the cytoskeleton-rich leading edge and at cell adhesions.
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Diagnostic accuracy of non-invasive fetal RhD genotyping using cell-free fetal DNA: a meta analysis.
J. Matern. Fetal. Neonatal. Med.
PUBLISHED: 02-10-2014
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Abstract Objective: To determine the diagnostic accuracy, validity, current limitations of, and possible solutions to, fetal RhD genotyping from maternal blood based on existing studies written in English.
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Three new diterpenoid alkaloids from the roots of Aconitum duclouxii.
J Asian Nat Prod Res
PUBLISHED: 02-05-2014
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Three new C??-diterpenoid alkaloids, ducloudines C (1), D (2), and E (3), were isolated from the roots of Aconitum duclouxii. Their structures were established on the basis of extensive spectroscopic analyses. Ducloudine C (1) is the first aconitine-type C??-diterpenoid alkaloid with a C=O group at C-3 and a C=C bond between C-1 and C-2. All compounds were tested for their biological activities against one pathogenic fungi and two pathogenic bacteria.
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Purification, crystallization and preliminary X-ray data collection of the N-terminal domain of the 26S proteasome regulatory subunit p27 and its complex with the ATPase domain of Rpt5 from Mus musculus.
Acta Crystallogr F Struct Biol Commun
PUBLISHED: 01-21-2014
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The protein 26S proteasome regulatory subunit p27 is one of the four chaperones that help in the assembly of the 19S regulatory particle (RP) of the 26S proteasome. In the present work, the N-terminus of p27 (residues 1-128) from Mus musculus was cloned, expressed, purified and crystallized alone and in complex with the C-terminal ATPase domain of Rpt5 (residues 173-442). The crystals of p27((1-128)) diffracted to 1.7 Å resolution and belonged to space group P212121, with unit-cell parameters a = 26.79, b = 30.39, c = 145.06 Å. Resolution-dependent Matthews coefficient probability analysis suggested the presence of only one molecule per asymmetric unit, with 40.5% solvent content and a VM value of 2.02 Å(3) Da(-1). The crystal of the p27((1-128))-Rpt5((173-442)) complex diffracted to 4 Å resolution and belonged to space group P222, with unit-cell parameters a = 75.93, b = 76.08, c = 336.85 Å. The presence of four heterodimers in the asymmetric unit with 53.2% solvent content and a VM value of 2.63 Å(3) Da(-1) or five heterodimers in the asymmetric unit with 41.5% solvent content and a VM value of 2.10 Å(3) Da(-1) is assumed.
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Phenolic extracts from Rhus verniciflua Stokes bark by decompressing inner ebullition and their antioxidant activities.
Nat. Prod. Res.
PUBLISHED: 01-17-2014
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Decompressing inner ebullition (DIE) can reduce the extraction liquid boiling point and polyphenols oxidation in the extraction process. The aim of this study is to optimise the phenolic extraction process by DIE and to examine the antioxidant activities. The extraction process parameters were observed by central composite design. The antioxidant activity was measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing power assays. The results showed that the optimal extraction condition is extract time of 90 min, temperature of 45°C, solid-liquid ratio of 1:20 g/mL, vacuum degree of - 0.08 MPa, ethanol concentration of 60%, while the phenolic content was 5.4%. The phenolic extracts from Rhus verniciflua Stokes bark had better antioxidant activities; the antioxidant activity (IC50) of the DIE was 20 ?g/mL by the DPPH method. The reducing power of the phenolic extracts was significantly related to their total phenolic content (R = 0.9903). The results presented show that the DIE method is an effective method for polyphenols extraction.
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Production of indirubin from tryptophan by recombinant Escherichia coli containing naphthalene dioxygenase genes from Comamonas sp. MQ.
Appl. Biochem. Biotechnol.
PUBLISHED: 01-16-2014
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Indirubin, a red isomer of indigo, can be used for the treatment of various chronic diseases. However, the microbial production of indirubin did not receive much attention probably due to its low yield compared with indigo. In this study, the recombinant Escherichia coli containing the naphthalene dioxygenase (NDO) genes from Comamonas sp. MQ was used to produce indirubin from tryptophan. To enhance the production of indirubin, the induction conditions for NDO expression were optimized. The optimal induction conditions were carried out with 0.5 mM isopropyl-?-D-thiogalactopyranoside at 30 °C when cells were grown to OD600 ? 1.20. Subsequently, the effects of medium composition on indirubin production were investigated by response surface methodology, and 9.37 ± 1.01 mg/l indirubin was produced from 3.28 g/l tryptophan. Meanwhile, the indirubin production was further improved by adding 2-oxindole and isatin to the tryptophan medium after induction. About 57.98 ± 2.62 mg/l indirubin was obtained by the addition of 500 mg/l 2-oxindole after 1-h induction, which was approximately 6.2-fold to that without additional 2-oxindole. The present study provided a possible way to improve the production of indirubin and should lay the foundation for the application of microbial indirubin production.
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Effect of CLN3 silencing by RNA interference on the proliferation and apoptosis of human colorectal cancer cells.
Biomed. Pharmacother.
PUBLISHED: 01-15-2014
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Apoptosis constitutes a system for the removal of aged, or damaged cells, which is regulated by the interplay of pro-apoptotic and antiapoptotic proteins. Previous study has shown that Juvenile Batten disease protein, CLN3, is antiapoptotic gene in NT2 neuronal precursor cells and a few types of cancers. However, in colorectal cancer, whether CLN3 also play its antiapoptotic role and the effect of targeted controlling CLN3 on the biological behavior of human colorectal cancer cell is unknown. We employed the sequence-specific siRNA silencing the CLN3 gene and investigated its effects on growth and apoptosis of colorectal cancer HCT116 cells, which has highest elevation of CLN3 expression among four colorectal cancer cell lines. After CLN3 specific siRNA transfection, mRNA and protein expression levels of CLN3 in HCT116 cells were noticeably decreased. Moreover, CLN3-siRNA inhibited the proliferation of colorectal cancer cells, promoted their apoptosis and induced G0/G1 cell cycle arrest. Our current study demonstrated that CLN3 was expressed in colorectal cancer cells at a high frequency. Moreover, CLN3 down-regulation with RNA interference can inhibit proliferation, apoptosis, and cell cycle progression of colorectal cancer cells. Our study represented a potential new approach to understanding the role of CLN3 in cancer and provides a potential novel strategy colorectal cancer therapy.
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Characterization of mesenchymal stem cells under the stimulation of Toll-like receptor agonists.
Dev. Growth Differ.
PUBLISHED: 01-13-2014
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Infective factors cause the perpetuation of inflammation as a result of the permanent exposure of the immune system to exogenous or endogenous products of virus or bacteria. Mesenchymal stem cells (MSCs) can be exposed to this infective environment, which may change the characteristics and therapeutic potency of these MSCs. MSCs have the ability to repair damaged and inflamed tissues and regulate immune responses. In this study, we demonstrated that MSCs express functional Toll-like receptors (TLR) 3 and 4, the Toll-like receptor families that recognize the signals of viral and bacterial mimics, respectively. The specific stimulations did not affect the self-renewal and apoptosis capabilities of MSCs but instead promoted their differentiation into the adipocytes and osteoblasts with the TLR3 ligand. The reverse of these results were obtained with the TLR4 ligand. The migration of the MSCs to stimulate either of the two specific ligands was inhibited at different times, whereas the immunogenicity and immunosuppressive properties of the MSCs were not weakened unlike in the MSCs group. These results suggest that TLR3 and TLR4 stimulation affect the characterization of MSCs.
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Catalytic performance and molecular dynamic simulation of immobilized CC bond hydrolase based on carbon nanotube matrix.
Colloids Surf B Biointerfaces
PUBLISHED: 01-13-2014
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Carbon nanotube (CNT) has been proved to be a kind of novel support for enzyme immobilization. In this study, we tried to find the relationship between conformation and catalytic performance of immobilized enzyme. Two CC bond hydrolases BphD and MfphA were immobilized on CNTs (SWCNT and MWCNT) via physical adsorption and covalent attachment. Among the conjugates, the immobilized BphD on chemically functionalized SWCNT (BphD-CSWCNT) retained the highest catalytic efficiency (kcat/Km value) compared to free BphD (92.9%). On the other hand, when MfphA bound to pristine SWCNT (MfphA-SWCNT), it was completely inactive. Time-resolved fluorescence spectrum indicated the formation of static ground complexes during the immobilization processes. Circular dichroism (CD) showed that the secondary structures of immobilized enzymes changed in varying degrees. In order to investigate the inhibition mechanism of MfphA by SWCNT, molecular dynamics simulation was employed to analyze the adsorption process, binding sites and time evolution of substrate tunnels. The results showed that the preferred binding sites (Trp201 and Met81) of MfphA for SWCNT blocked the main substrate access tunnel, thus making the enzyme inactive. The "tunnel-block" should be a novel possible inhibition mechanism for enzyme-nanotube conjugate.
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Plasmakinetic Enucleation of the Prostate Compared with Open Prostatectomy for Prostates Larger Than 100 Grams: A Randomized Noninferiority Controlled Trial with Long-term Results at 6 Years.
Eur. Urol.
PUBLISHED: 01-13-2014
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Studies have demonstrated that plasmakinetic enucleation of the prostate (PKEP) and open prostatectomy (OP) have equivalent short-term efficacy for large prostates, but no comparison concerning their long-term results was reported.
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PGC-1? integrates glucose metabolism and angiogenesis in multiple myeloma cells by regulating VEGF and GLUT-4.
Oncol. Rep.
PUBLISHED: 01-09-2014
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Human peroxisome proliferator-activated receptor-? coactivator 1? (PGC-1?) is a key coactivator in the regulation of gene transcriptional activity in normal tissues. However, it is not clear whether it is involved in the angiogenesis and metabolism of multiple myeloma (MM). The aim of the present study was to investigate the role of PGC-1? in MM. Small interfering RNA (siRNA) was used to inhibit PGC-1? expression in RPMI-8226 cells. An endothelial cell migration assay was performed using transwell chambers and the expression of PGC-1?, estrogen-related receptor-? (ERR-?), vascular endothelial growth factor (VEGF) and glucose transporter-4 (GLUT-4) was tested by reverse transcription-polymerase chain reaction (RT-PCR). The protein expression of PGC-1?, ERR-? and GLUT-4 was assayed by western blot analysis. Lastly, RPMI-8226 cell proliferation was evaluated using CCK-8 assay. VEGF and GLUT-4 mRNA levels were decreased in cells treated with siRNA targeting PGC-1?, as was the level of GLUT-4 protein. Endothelial cell migration was significantly reduced when these cells were cultured with culture medium from RPMI-8226 cells treated with siPGC-1?. The proliferation rates at 24 and 48 h were suppressed by PGC-1? inhibition. Our results showed that inhibition of PGC-1? suppresses cell proliferation probably by downregulation of VEGF and GLUT-4. The present study suggests that PGC-1? integrates angiogenesis and glucose metabolism in myeloma through regulation of VEGF and GLUT-4.
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A mechanism regulating G protein-coupled receptor signaling that requires cycles of protein palmitoylation and depalmitoylation.
J. Biol. Chem.
PUBLISHED: 01-02-2014
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Reversible attachment and removal of palmitate or other long-chain fatty acids on proteins has been hypothesized, like phosphorylation, to control diverse biological processes. Indeed, palmitate turnover regulates Ras trafficking and signaling. Beyond this example, however, the functions of palmitate turnover on specific proteins remain poorly understood. Here, we show that a mechanism regulating G protein-coupled receptor signaling in neuronal cells requires palmitate turnover. We used hexadecyl fluorophosphonate or palmostatin B to inhibit enzymes in the serine hydrolase family that depalmitoylate proteins, and we studied R7 regulator of G protein signaling (RGS)-binding protein (R7BP), a palmitoylated allosteric modulator of R7 RGS proteins that accelerate deactivation of Gi/o class G proteins. Depalmitoylation inhibition caused R7BP to redistribute from the plasma membrane to endomembrane compartments, dissociated R7BP-bound R7 RGS complexes from Gi/o-gated G protein-regulated inwardly rectifying K(+) (GIRK) channels and delayed GIRK channel closure. In contrast, targeting R7BP to the plasma membrane with a polybasic domain and an irreversibly attached lipid instead of palmitate rendered GIRK channel closure insensitive to depalmitoylation inhibitors. Palmitate turnover therefore is required for localizing R7BP to the plasma membrane and facilitating Gi/o deactivation by R7 RGS proteins on GIRK channels. Our findings broaden the scope of biological processes regulated by palmitate turnover on specific target proteins. Inhibiting R7BP depalmitoylation may provide a means of enhancing GIRK activity in neurological disorders.
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Protective effects of let-7a and let-7b on oxidized low-density lipoprotein induced endothelial cell injuries.
PLoS ONE
PUBLISHED: 01-01-2014
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Lectin-like low-density lipoprotein receptor 1 (LOX-1) is a receptor for oxidized low density lipoprotein (oxLDL) in endothelial cells. The activation of LOX-1 by oxLDL stimulates the apoptosis and dysfunction of endothelial cells, and contributes to atherogenesis. However, the regulatory factors for LOX-1 are still unclear. MicroRNAs are small, endogenous, non-coding RNAs that regulate gene expressions at a post-transcriptional level. The let-7 family is the second microRNA been discovered, which plays important roles in cardiovascular diseases. Let-7a and let-7b were predicted to target LOX-1 3'-UTR and be highly expressed in endothelial cells. The present study demonstrated that LOX-1 was a target of let-7a and let-7b. They inhibited the expression of LOX-1 by targeting the positions of 310-316 in LOX-1 3'-UTR. Over-expression of let-7a and let-7b inhibited the oxLDL-induced endothelial cell apoptosis, NO deficiency, ROS over-production, LOX-1 upregulation and endothelial nitric oxide synthase (eNOS) downregulation. Moreover, we found that oxLDL treatment induced p38MAPK phosphorylation, NF-?B nuclear translocation, I?B degradation and PKB dephosphorylation. Let-7a or let-7b over-expression attenuated these alterations significantly. The present study may provide a new insight into the protective properties of let-7a and let-7b in preventing the endothelial dysfunction associated with cardiovascular disease, such as atherosclerosis.
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A genetically modified protein-based hydrogel for 3D culture of AD293 cells.
PLoS ONE
PUBLISHED: 01-01-2014
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Hydrogels have strong application prospects for drug delivery, tissue engineering and cell therapy because of their excellent biocompatibility and abundant availability as scaffolds for drugs and cells. In this study, we created hybrid hydrogels based on a genetically modified tax interactive protein-1 (TIP1) by introducing two or four cysteine residues in the primary structure of TIP1. The introduced cysteine residues were crosslinked with a four-armed poly (ethylene glycol) having their arm ends capped with maleimide residues (4-armed-PEG-Mal) to form hydrogels. In one form of the genetically modification, we incorporated a peptide sequence 'GRGDSP' to introduce bioactivity to the protein, and the resultant hydrogel could provide an excellent environment for a three dimensional cell culture of AD293 cells. The AD293 cells continued to divide and displayed a polyhedron or spindle-shape during the 3-day culture period. Besides, AD293 cells could be easily separated from the cell-gel constructs for future large-scale culture after being cultured for 3 days and treating hydrogel with trypsinase. This work significantly expands the toolbox of recombinant proteins for hydrogel formation, and we believe that our hydrogel will be of considerable interest to those working in cell therapy and controlled drug delivery.
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Upregulation of regulator of G-protein signaling 2 in the sclera of a form deprivation myopic animal model.
Mol. Vis.
PUBLISHED: 01-01-2014
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Scleral remodeling is an important mechanism underlying the development of myopia. Atropine, an antagonist of G protein-coupled muscarinic receptors, is currently used as an off-label treatment for myopia. Regulator of G-protein signaling 2 (RGS2) functions as an intracellular selective inhibitor of muscarinic receptors. In this study we measured scleral RGS2 expression and scleral remodeling in an animal model of myopia in the presence or absence of atropine treatment.
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Neural network assisted inverse dynamic guidance for terminally constrained entry flight.
ScientificWorldJournal
PUBLISHED: 01-01-2014
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This paper presents a neural network assisted entry guidance law that is designed by applying Bézier approximation. It is shown that a fully constrained approximation of a reference trajectory can be made by using the Bézier curve. Applying this approximation, an inverse dynamic system for an entry flight is solved to generate guidance command. The guidance solution thus gotten ensures terminal constraints for position, flight path, and azimuth angle. In order to ensure terminal velocity constraint, a prediction of the terminal velocity is required, based on which, the approximated Bézier curve is adjusted. An artificial neural network is used for this prediction of the terminal velocity. The method enables faster implementation in achieving fully constrained entry flight. Results from simulations indicate improved performance of the neural network assisted method. The scheme is expected to have prospect for further research on automated onboard control of terminal velocity for both reentry and terminal guidance laws.
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Alkaloids from an endophytic streptomyces sp. YIM66017.
Nat Prod Commun
PUBLISHED: 12-21-2013
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Three alkaloids, flavensomycinoic acid (1), a linear polyketide, alpiniamide (2), and cyclo (L-Trp-L-Ala) (3), were isolated from the culture filtrate of endophytic Streptomyces sp. YIM66017 from Alpinia oxyphylla. Their structures were elucidated by spectroscopic analysis and the structure of 1 was confirmed by X-ray crystallographic analysis. Compound 1 was isolated from a natural source for the first time, and compound 2 is a new compound. Compound 1 showed cytotoxicity to MCF-7 with an IC50 value of 17.0 microM.
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Molecular Epidemiological Characteristics of Streptococcus pyogenes Strains Involved in an Outbreak of Scarlet Fever in China, 2011.
Biomed. Environ. Sci.
PUBLISHED: 12-17-2013
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To investigate molecular characterization of streptococcus pyogenes isolates involved in an outbreak of scarlet fever in China in 2011.
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VMP1 related autophagy and apoptosis in colorectal cancer cells: Vmp1 regulates cell death.
Biochem. Biophys. Res. Commun.
PUBLISHED: 12-16-2013
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Vacuole membrane protein 1 (VMP1) is an autophagy-related protein and identified as a key regulator of autophagy in recent years. In pancreatic cell lines, VMP1-dependent autophagy has been linked to positive regulation of apoptosis. However, there are no published reports on the role of VMP1 in autophagy and apoptosis in colorectal cancers. Therefore, to address this gap of knowledge, we decided to interrogate regulation of autophagy and apoptosis by VMP1. We have studied the induction of autophagy by starvation and rapamycin treatment in colorectal cell lines using electron microscopy, immunofluorescence, and immunoblotting. We found that starvation-induced autophagy correlated with an increase in VMP1 expression, that VMP1 interacted with BECLIN1, and that siRNA mediated down-regulation of VMP1-reduced autophagy. Next, we examined the relationship between VMP1-dependent autophagy and apoptosis and found that VMP1 down-regulation sensitizes cells to apoptosis and that agents that induce apoptosis down-regulate VMP1. In conclusion, similar to its reported role in other cell types, VMP1 is an important regulator of autophagy in colorectal cell lines. However, in contrast to its role in pancreatic cell lines, in colorectal cancer cells, VMP1-dependent autophagy appears to be pro-survival rather than pro-cell death.
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A new cyclic tetrapeptide from an endophytic Streptomyces sp. YIM67005.
Nat. Prod. Res.
PUBLISHED: 12-04-2013
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One new cyclic tetrapeptide, cyclo(l-Tyr-l-Pro-l-Phe-trans-4-hydroxy-l-Pro) (1), together with two known cyclodipeptides, cyclo(l-Phe-trans-4-hydroxy-l-Pro) (2) and cyclo(l-Val-l-Tyr) (3), were isolated from the fermentation broth of Streptomyces sp. YIM67005 associated with Inula cappa DC. The planar structure of compound 1 was determined on the basis of spectroscopic techniques, while the absolute configurations of the amino acid residues were determined by the application of the advanced Marfey method. The cytotoxicity and antimicrobial activity of compound 1 were investigated.
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Genome Sequence of Dyella ginsengisoli Strain LA-4, an Efficient Degrader of Aromatic Compounds.
Genome Announc
PUBLISHED: 11-23-2013
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Dyella ginsengisoli strain LA-4 can efficiently degrade environmental pollutants such as biphenyl and azo dyes. Here, we present a 4.55-Mb draft genome sequence of strain LA-4, which may provide further insights into the molecular mechanism in environmental pollution remediation.
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[Partial rectus muscle transposition for strabismus with lateral rectus muscles paralysis].
Zhonghua Yan Ke Za Zhi
PUBLISHED: 11-22-2013
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To investigate surgical approach for paralytic strabismus with lateral rectus muscles paralysis and evaluate its clinical effects.
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A bis-boronic acid modified electrode for the sensitive and selective determination of glucose concentrations.
Analyst
PUBLISHED: 10-22-2013
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A bis-boronic acid modified electrode for the sensitive and selective determination of glucose concentrations has been developed. The electrochemical characteristics of the sensor with added saccharides were investigated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The bis-boronic acid modified electrode was both sensitive and selective for glucose.
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Cloning and analysis of bile salt hydrolase genes from Lactobacillus plantarum CGMCC No. 8198.
Biotechnol. Lett.
PUBLISHED: 10-16-2013
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Genes coding for bile salt hydrolase of Lactobacillus plantarum CGMCC 8198, a novel probiotic strain isolated from silage, were identified, analyzed and cloned. L. plantarum strongly resisted the inhibitory effects of bile salts and also decreased serum cholesterol levels by 20 % in mice with hypercholesterolemia. Using RT-PCR analysis, bsh2, bsh3 and bsh4 were upregulated by bile salts in a dose-dependent manner. All three bsh genes had high similarity with those of other Lactobacillus strains. All three recombinant BSHs had high activities for the hydrolysis of glycodeoxycholic acids and taurodeoxycholic acids.
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Fiber-based tunable microcavity fluidic dye laser.
Opt Lett
PUBLISHED: 10-10-2013
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We investigate a tunable fluidic dye laser formed by a microcavity filled with a dye solution. We achieve a wide 18 nm tunability of the laser wavelength by controlling the cavity length for the first time. The microcavity is made of a silica capillary and two aligned fibers with end faces Au-coated. The Rhodamine 6G dye solution flowing through the microcavity is pumped by 532 nm wavelength laser pulses. Laser emission around 570 nm in the form of TE mode with a threshold of about 58???J/pulse is obtained. This work suggests a fiber-based convenient approach to achieve wavelength tunability and integration with lab-on-a-chip systems.
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Histone acetyltransferase p300 promotes MKL1-mediated transactivation of catechol-O-methyltransferase gene.
Acta Biochim. Biophys. Sin. (Shanghai)
PUBLISHED: 10-03-2013
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Previous studies have revealed that histone acetyltransferase p300 is recruited to the promoters of certain cardiac and smooth muscle specific genes to enhance the transactivation activity of myocardin, which is a master regulator in cardiovascular differentiation and development. Here, we found that the gene encoding catechol-O-methyltransferase (COMT), an important metabolic enzyme catalyzing the conversion of estrogen, is also a target gene of myocardin-related transcription factors (MRTFs). Megakaryoblastic leukemia 1 (MKL1, also named MRTF-A) and p300 could synergistically augment the expression of COMT gene, increase the metabolic rate of estrogen, and thus reduce the proliferation of MCF-7 breast cancer cells stimulated by estrogen.
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Myocardin-related transcription factor A is up-regulated by 17?-estradiol and promotes migration of MCF-7 breast cancer cells via transactivation of MYL9 and CYR61.
Acta Biochim. Biophys. Sin. (Shanghai)
PUBLISHED: 10-01-2013
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Many lines of evidence have suggested that estrogen plays important roles not only in the initiation and proliferation of breast cancer, but also in cancer metastasis. However, the mechanistic basis of the latter events is poorly understood. In addition, recent studies have suggested that myocardin-related transcription factor A (MRTF-A) might be related to cancer metastasis. However, as reports are contradictory, certain of its roles still remain confusing. In the present study, we showed that excessive 17?-estradiol could promote the migration of MCF-7 breast cancer cells and up-regulate the expression of MRTF-A, myosin regulatory light chain 9 (MYL9), and cysteine-rich angiogenic inducer 61 (CYR61). Overexpression of MRTF-A significantly promoted the migration of MCF-7 cells through its transactivation effects on MYL9 and CYR61 genes, while RNA interference-mediated knockdown of MRTF-A strongly inhibited transcription and expression of the target genes and reduced the migration ability of MCF-7 cells. These results provided novel evidence supporting the metastasis-promoting functions of MRTF-A, and implied that MRTF-A might be a switch for the estrogen pathway to change its proliferation-promoting roles into migration-stimulating roles in breast cancer.
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Academic Achievement and Loneliness of Migrant Children in China: School Segregation and Segmented Assimilation.
Comp Educ Rev
PUBLISHED: 10-01-2013
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Chinas rural-urban migration presents a significant educational challenge. This study uses theories of segmented assimilation and school segregation to measure the assimilation and well-being of migrant children who attend either Beijings public schools or its informal migrant schools. Controling for other factors, we find poorer achievement and greater loneliness among migrant children who are isolated in migrant schools than similar migrant students enrolled in regular urban public schools. We show there is little difference in learning outcome or loneliness between urban native children and migrant children who attend public schools. We further discuss similarities and differences between the experiences of migrant children in China and immigrant children in the United States.
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[Self-adaptive beamforming method based on plane wave ultrasound imaging].
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi
PUBLISHED: 09-25-2013
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In order to improve the resolution, contrast and frame rate of ultrasound imaging, it is necessary to design an adaptive beamforming method for plane wave ultrasound imaging. An optimized minimum variance algorithm that suits plane wave ultrasound imaging was proposed, based on the traditional minimum variance algorithm that combines with the subband beamforming as well as the forward-backward spatial smoothing method in the frequency domain. To verify the effectiveness of the improved algorithm, the matlab software was used. Simulation results showed that full width at half maximum and peak side-lobe level of Optimized MV, Conventional MV, DAS boxcar, and Linear scan methods were 0.08, 0.36, 0.92, 1.42 dB, and -41.1, - 37.3, -16.9, - 34.1 dB, respectively. The improved algorithm can significantly improve the image resolution and contrast, particularly applicable to plane wave ultrasound imaging, compared with the conventional minimum variance algorithm and traditional delay-and-sum method.
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Structural insights into Paf1 complex assembly and histone binding.
Nucleic Acids Res.
PUBLISHED: 09-14-2013
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The highly conserved Paf1 complex (PAF1C) plays critical roles in RNA polymerase II transcription elongation and in the regulation of histone modifications. It has also been implicated in other diverse cellular activities, including posttranscriptional events, embryonic development and cell survival and maintenance of embryonic stem cell identity. Here, we report the structure of the human Paf1/Leo1 subcomplex within PAF1C. The overall structure reveals that the Paf1 and Leo1 subunits form a tightly associated heterodimer through antiparallel beta-sheet interactions. Detailed biochemical experiments indicate that Leo1 binds to PAF1C through Paf1 and that the Ctr9 subunit is the key scaffold protein in assembling PAF1C. Furthermore, we show that the Paf1/Leo1 heterodimer is necessary for its binding to histone H3, the histone octamer, and nucleosome in vitro. Our results shed light on the PAF1C assembly process and substrate recognition during various PAF1C-coordinated histone modifications.
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Evaluation on the efficacy and safety of domestic bivalirudin during percutaneous coronary intervention.
Chin. Med. J.
PUBLISHED: 08-29-2013
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Bivalirudin was widely used as an anticoagulant during coronary interventional procedure in western countries. However, it was not available in China before this clinical trial was designed. This randomized, single-blind and multicenter clinical trial aimed to evaluate the efficacy and the safety of domestic bivalirudin during percutaneous coronary intervention (PCI).
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Structural analysis of Mycobacterium tuberculosis ATP-binding cassette transporter subunit UgpB reveals specificity for glycerophosphocholine.
FEBS J.
PUBLISHED: 08-28-2013
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Tuberculosis (TB), caused by Mycobacterium tuberculosis, is one of the most devastating human diseases, and is responsible for ~ 2 million deaths worldwide each year. The nutritional requirements for the growth of mycobacteria have been extensively studied since the discovery of M. tuberculosis, but the essential nutrients for M. tuberculosis inside the human host and the identity of the corresponding transporters remain unknown. The UgpABCE transporter of M. tuberculosis is one of five putative permeases for carbohydrate uptake, and is genetically predicted to be an sn-glycerol 3-phosphate importer. We have determined the 1.5-Å crystal structure of M. tuberculosis UgpB, which has been reported to be a promising vaccine candidate against TB. M. tuberculosis UgpB showed no detectable binding activity for sn-glycerol 3-phosphate by isothermal titration calorimetry, but instead showed a preference for glycerophosphocholine (GPC). M. tuberculosis UgpB largely resembles its Escherichia coli homolog, but with the critical Trp169 in the substrate-binding site of E. coli UgpB replaced by Leu205. Mutation of Leu205 abolishes GPC binding, suggesting that Leu205 is a determinant of GPC binding. The work reported here not only contributes to our understanding of the carbon and phosphate sources utilized by M. tuberculosis inside the human host, but will also promote improvements in TB chemotherapy.
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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.