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Find video protocols related to scientific articles indexed in Pubmed.
Accurate estimation of haplotype frequency from pooled sequencing data and cost-effective identification of rare haplotype carriers by overlapping pool sequencing.
Bioinformatics
PUBLISHED: 10-09-2014
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A variety of hypotheses have been proposed for finding the missing heritability of complex diseases in genome-wide association studies. Studies have focused on the value of haplotype to improve the power of detecting associations with disease. To facilitate haplotype-based association analysis, it is necessary to accurately estimate haplotype frequencies of pooled samples.
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Duodenal absorption and tissue utilization of dietary heme and nonheme iron differ in rats.
J. Nutr.
PUBLISHED: 09-10-2014
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Dietary heme contributes to iron intake, yet regulation of heme absorption and tissue utilization of absorbed heme remains undefined.
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Sandwichlike magnesium silicate/reduced graphene oxide nanocomposite for enhanced Pb²? and methylene blue adsorption.
ACS Appl Mater Interfaces
PUBLISHED: 08-07-2014
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A sandwichlike magnesium silicate/reduced graphene oxide nanocomposite (MgSi/RGO) with high adsorption efficiency of organic dye and lead ion was synthesized by a hydrothermal approach. MgSi nanopetals were formed in situ on both sides of RGO sheets. The nanocomposite with good dispersion of nanopetals exhibits a high specific surface area of 450 m(2)/g and a good mass transportation property. Compared to MgSi and RGO, the mechanical stability and adsorption capacity of the nanocomposite is significantly improved due to the synergistic effect. The maximum adsorption capacities for methylene blue and lead ion are 433 and 416 mg/g, respectively.
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C60 fullerenol as an active and stable catalyst for the synthesis of cyclic carbonates from CO2 and epoxides.
Chem. Commun. (Camb.)
PUBLISHED: 07-25-2014
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C60 fullerenol was found to be a highly active, selective and stable catalyst for cycloaddition between CO2 and epoxides to produce various cyclic carbonates with excellent yields (89-99%). A solid/liquid interfacial hydrogen-bond assisted mechanism was proposed to account for its high efficiency.
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Placental heme receptor LRP1 correlates with the heme exporter FLVCR1 and neonatal iron status.
Reproduction
PUBLISHED: 06-19-2014
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LDL receptor-related protein 1 (LRP1) is a transmembrane receptor highly expressed in human placenta. It was recently found to be the receptor for heme and its plasma-binding protein hemopexin (Hx) and is integral to systemic heme clearance. Little is known about systemic concentrations of Hx during pregnancy and whether maternal Hx and placental LRP1 contributes to fetal iron (Fe) homeostasis during pregnancy. We hypothesized that placental LRP1 would be upregulated in maternal/neonatal Fe insufficiency and would be related to maternal circulating Hx. Placental LRP1 expression was assessed in 57 pregnant adolescents (14-18 years) in relationship with maternal and cord blood Fe status indicators (hemoglobin (Hb), serum ferritin, transferrin receptor), the Fe regulatory hormone hepcidin and serum Hx. Hx at mid-gestation correlated positively with Hb at mid-gestation (r=0.35, P=0.02) and Hx at delivery correlated positively with cord hepcidin (r=0.37, P=0.005). Placental LRP1 protein expression was significantly higher in women who exhibited greater decreases in serum Hx from mid-gestation to term (r=0.28, P=0.04). Significant associations were also found between placental LRP1 protein with cord hepcidin (r=-0.29, P=0.03) and placental heme exporter feline leukemia virus C receptor 1 (r=0.34, P=0.03). Our data are consistent with a role for placental heme Fe utilization in supporting fetal Fe demands.
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Quantitative group testing-based overlapping pool sequencing to identify rare variant carriers.
BMC Bioinformatics
PUBLISHED: 06-10-2014
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Genome-wide association studies have revealed that rare variants are responsible for a large portion of the heritability of some complex human diseases. This highlights the increasing importance of detecting and screening for rare variants. Although the massively parallel sequencing technologies have greatly reduced the cost of DNA sequencing, the identification of rare variant carriers by large-scale re-sequencing remains prohibitively expensive because of the huge challenge of constructing libraries for thousands of samples. Recently, several studies have reported that techniques from group testing theory and compressed sensing could help identify rare variant carriers in large-scale samples with few pooled sequencing experiments and a dramatically reduced cost.
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Tunable synthesis of hexagram-shaped hematite iron oxide microcrystals with shape-dependent magnetic properties.
J Nanosci Nanotechnol
PUBLISHED: 04-25-2014
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Uniform hexagram-shaped alpha-Fe2O3 microcrystals with tunable morphologies were fabricated by a facile hydrothermal method followed by annealing in air. The highly anisotropic hexagram-shaped alpha-Fe2O3 particles with the higher coercivity forces and remannent magnetizations showed weak ferromagnetic behaviors at room temperature and displayed the typical shape-dependent magnetic behaviors.
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Detection of human bocavirus in children with acute respiratory tract infections in lanzhou and nanjing, china.
Biomed. Environ. Sci.
PUBLISHED: 04-20-2014
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The aim of this study was to explore the prevalent characteristics of HBoV1 and its co-infection.
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Effects on liver hydrogen peroxide metabolism induced by dietary selenium deficiency or excess in chickens.
Biol Trace Elem Res
PUBLISHED: 03-04-2014
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To determine the relationship between dietary selenium (Se) deficiency or excess and liver hydrogen peroxide (H2O2) metabolism in chickens, 1-day-old chickens received insufficient Se (0.028 mg Se per kg of diet) or excess Se (3.0 or 5.0 mg Se per kg of diet) in their diets for 8 weeks. Body and liver weight changes, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, H2O2 content, and activities and mRNA levels of enzymes associated with H2O2 metabolism (catalase (CAT) and superoxide dismutase (SOD) 1-3) were determined in the liver. This study showed that Se deficiency or excess Se intake elicited relative severe changes. Se deficiency decreased growth, while Se excess promoted growth in chickens. Both diets vastly altered the liver function, but no obvious histopathological changes were observed in the liver. Se deficiency significantly lowered SOD and CAT activities, and the H2O2 content in the liver and serum increased. Se excess (3.0 mg/kg) decreased SOD and CAT activities with changes in their mRNA levels, and the H2O2 content increased. The larger Se excess (5.0 mg/kg) showed more serious effects but was not fatal. These results indicated that the H2O2 metabolism played a destructive role in the changes in bird liver function induced by Se deficiency or excess.
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A monoclonal antibody targeting neuropilin-1 inhibits adhesion of MCF7 breast cancer cells to fibronectin by suppressing the FAK/p130cas signaling pathway.
Anticancer Drugs
PUBLISHED: 03-04-2014
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Neuropilin-1 (NRP-1) is a nontyrosine kinase coreceptor for semaphorin 3A and the vascular endothelial growth factor involved in tumor angiogenesis, growth, and metastasis and is regarded as a promising target for cancer therapy. In the present study, we investigated the effects of an anti-NRP-1 monoclonal antibody (mAb) that we generated for MCF7 breast cancer cellular adhesion studies. MTT, colony formation, and adhesion assays showed that our anti-NRP-1 mAb dose-dependently inhibited MCF7 proliferation and fibronectin adhesion, leading to a rounded cellular morphology. Further, rhodamine phalloidin stain revealed that fibronectin-dependent formation of actin stress fibers was inhibited by anti-NRP-1 mAb. Immunoprecipitation and western blot showed that anti-NRP-1 mAb treatment inhibited the formation of NRP-1-?5?1 integrin complexes and suppressed the phosphorylation of focal adhesion kinase and p130cas in MCF7 cells. These findings contribute to further understanding the NRP-1 function in cell adhesion and tumor metastasis. Moreover, our anti-NRP-1 mAb is a prospective drug candidate for tumor treatment.
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Intrinsic correlation of oligonucleotides: a novel genomic signature for metagenome analysis.
J. Theor. Biol.
PUBLISHED: 02-26-2014
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Because a vast majority (99%) of microbes in a given community is likely to be non-cultivable, metagenomics has gradually entered the mainstream of microbial research methods. With the development of high-throughput sequencing techniques, an increasing number of sequencing read data sets of metagenomes from various microbial communities have become available. For these data sets, metagenomic analysis based on mapping reads to microbial genomes has been hampered by the limited number of microbial genomes that are available. Further, this type of analysis is computationally intensive. Thus alignment-free methods, which characterize the sequencing reads with a genomic signature instead of with genomic alignments, can be applied. However, the main requirement of these alignment-free methods is a stable genomic signature that performs reliably. Here, we propose a novel genomic signature of microbial genomes called the intrinsic correlation of oligonucleotides (ICOs). This signature represents the quantification of an intrinsic relationship between any two oligonucleotides. We analyzed microbial genomes at different taxonomic levels using ICO profiles and confirmed the wide availability of useful ICOs. We used intra-genomic and inter-genomic distances and relational grades to evaluate the performance of ICOs as a genomic signature. The results of these experiments showed that ICOs can characterize microbial genomes well, and ICOs were better at distinguishing species than tetranucleotide composition, not only in terms of whole genomes but also in terms of sequence fragments. In addition, we evaluated the performance of a hybrid feature that combined ICOs and tetranucleotide composition. The experimental results showed that the hybrid feature performed better than ICOs or tetranucleotide composition alone. ICOs can characterize microbial genomes successfully and are capable of distinguishing organisms at different taxonomic levels. ICOs perform better than tetranucleotide composition in characterizing microbial genomes. The hybrid feature that used a combination of the two kinds of sequence features had advantages over a single sequence feature.
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Placental CYP27B1 and CYP24A1 expression in human placental tissue and their association with maternal and neonatal calcitropic hormones.
J. Clin. Endocrinol. Metab.
PUBLISHED: 01-28-2014
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Placental CYP27B1 may contribute to circulating maternal calcitriol concentrations across gestation, but determinants of CYP27B1 and CYP24A1 expression in term human placental tissue are not well established.
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Ischemic preconditioning attenuates brain injury induced by ischemia/reperfusion during moderate hypothermia low-flow procedures.
Int. J. Neurosci.
PUBLISHED: 01-24-2014
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We determined the effects of ischemic preconditioning (IP) on apoptosis in a rat model of brain injury induced by cerebral ischemia/reperfusion following a moderate hypothermic low-flow (MHLF) procedure.
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IL-10 Deficiency Increases Renal Ischemia-Reperfusion Injury.
Nephron Exp. Nephrol.
PUBLISHED: 01-17-2014
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Background: Renal ischemia-reperfusion (IR) injury is a frequent cause of acute kidney injury, which results in high morbidity and mortality. Inflammation is an important factor that is involved in kidney repair after renal IR injury. IL-10 is a potent anti-inflammatory cytokine that inhibits inflammatory pathways, but the role of IL-10 in repairing renal IR injury is not known. Here, we investigated the role of IL-10 in kidney repair after renal IR injury. Methods: We used an IL-10(-/-) mouse model and examined the serologic and histomorphology of kidney after IR injury. We also measured ki67, TNF-?, IL-6, and macrophages with immunohistochemistry or Western blotting. Results: There was a greater increase in serum creatinine in IL-10(-/-) mice than in wild-type (WT) mice. And compared with WT mice, IL-10(-/-) mice had increased histologic renal injury and decreased proliferation. Moreover, the expression of TNF-?, IL-6 and macrophages was clearly increased in IL-10(-/-) mice compared with the WT mice. Conclusion: These data reveal an important role for IL-10 in the improvement of renal IR injury, acting through suppression of inflammatory mediators, and that IL-10 would be a crucial target for the treatment of IR injury. © 2014 S. Karger AG, Basel.
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A core-shell-satellite structured Fe3O4@MS-NH2@Pd nanocomposite: a magnetically recyclable multifunctional catalyst for one-pot multistep cascade reaction sequences.
Nanoscale
PUBLISHED: 11-11-2013
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A hierarchical core-shell-satellite structured composite system Fe3O4@MS-NH2@Pd, which was composed of Pd nanoparticles well-dispersed on an amino group functionalized mesoporous silica (MS-NH2) nanosphere, and superparamagnetic Fe3O4 nanoparticles scattered inside the silica sphere, was prepared by using a facile procedure. The composite combined the catalytic properties of amino groups and Pd nanoparticles with superparamagnetic properties of magnetite into a single platform. This integrated nanosystem acted as an efficient magnetically recyclable noble metal-base multifunctional nanocatalyst and showed excellent catalytic activity, selectivity and stability for the direct synthesis of ?-alkylated nitriles under mild conditions through facile one-pot multistep cascade reaction sequences.
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[Comparison of two gastric cancer screening schemes in a high-risk population].
Zhonghua Zhong Liu Za Zhi
PUBLISHED: 09-24-2013
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To evaluate the effects of two gastric cancer screening schemes for early detection of gastric cancer in a high-risk population.
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A monoclonal antibody produced against Naked2.
Monoclon Antib Immunodiagn Immunother
PUBLISHED: 08-06-2013
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Naked2 (NKD2) is a member of the Naked family and negatively regulates canonical Wnt signaling. NKD2 may play a role in embryo development and tumor formation by affecting Wnt signaling. In the present study, we describe the establishment of a monoclonal antibody against NKD2 (anti-NKD2 MAb) through the hybridoma method. The purified anti-NKD2 MAb measured a titer of 2.56 × 10(5) against NKD2 by indirect ELISA. Western blot analysis, immunoprecipitation, and confocal microscope showed that the anti-NKD2 MAb can specifically combine NKD2 protein in SW480 and LOVO cells. Competitive inhibition assays of Western blot and indirect ELISA showed that the anti-NKD2 MAb can be blocked with NKD2(1-217) protein. The anti-NKD2 MAb would be helpful for further studies on the structure activity relationship, protein detecting, and cell-signaling pathway of NKD2.
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[Comparison study of endobronchial ultrasound-guided transbronchial needle aspiration and transbronchial needle aspiration for the diagnosis of hilar and mediastinal lesions].
Beijing Da Xue Xue Bao
PUBLISHED: 06-19-2013
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To compare the values of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and TBNA for the diagnosis of hilar and mediastinal lesions.
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Coating with mesoporous silica remarkably enhances the stability of the highly active yet fragile flower-like MgO catalyst for dimethyl carbonate synthesis.
Chem. Commun. (Camb.)
PUBLISHED: 06-04-2013
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Flower-like MgO is a highly effective catalyst for the synthesis of dimethyl carbonate through the transesterification method, and coating the catalyst with mesoporous silica significantly enhances the stability of the MgO catalyst.
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Identifying rare variants with optimal depth of coverage and cost-effective overlapping pool sequencing.
Genet. Epidemiol.
PUBLISHED: 04-23-2013
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Genome-wide association studies have identified hundreds of genetic variants associated with complex diseases although most variants identified so far explain only a small proportion of heritability, suggesting that rare variants are responsible for missing heritability. Identification of rare variants through large-scale resequencing becomes increasing important but still prohibitively expensive despite the rapid decline in the sequencing costs. Nevertheless, group testing based overlapping pool sequencing in which pooled rather than individual samples are sequenced will greatly reduces the efforts of sample preparation as well as the costs to screen for rare variants. Here, we proposed an overlapping pool sequencing to screen rare variants with optimal sequencing depth and a corresponding cost model. We formulated a model to compute the optimal depth for sufficient observations of variants in pooled sequencing. Utilizing shifted transversal design algorithm, appropriate parameters for overlapping pool sequencing could be selected to minimize cost and guarantee accuracy. Due to the mixing constraint and high depth for pooled sequencing, results showed that it was more cost-effective to divide a large population into smaller blocks which were tested using optimized strategies independently. Finally, we conducted an experiment to screen variant carriers with frequency equaled 1%. With simulated pools and publicly available human exome sequencing data, the experiment achieved 99.93% accuracy. Utilizing overlapping pool sequencing, the cost for screening variant carriers with frequency equaled 1% in 200 diploid individuals dropped to at least 66% at which target sequencing region was set to 30 Mb.
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Genome analysis and signature discovery for diving and sensory properties of the endangered Chinese alligator.
Cell Res.
PUBLISHED: 04-15-2013
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Crocodilians are diving reptiles that can hold their breath under water for long periods of time and are crepuscular animals with excellent sensory abilities. They comprise a sister lineage of birds and have no sex chromosome. Here we report the genome sequence of the endangered Chinese alligator (Alligator sinensis) and describe its unique features. The next-generation sequencing generated 314 Gb of raw sequence, yielding a genome size of 2.3 Gb. A total of 22 200 genes were predicted in Alligator sinensis using a de novo, homology- and RNA-based combined model. The genetic basis of long-diving behavior includes duplication of the bicarbonate-binding hemoglobin gene, co-functioning of routine phosphate-binding and special bicarbonate-binding oxygen transport, and positively selected energy metabolism, ammonium bicarbonate excretion and cardiac muscle contraction. Further, we elucidated the robust Alligator sinensis sensory system, including a significantly expanded olfactory receptor repertoire, rapidly evolving nerve-related cellular components and visual perception, and positive selection of the night vision-related opsin and sound detection-associated otopetrin. We also discovered a well-developed immune system with a considerable number of lineage-specific antigen-presentation genes for adaptive immunity as well as expansion of the tripartite motif-containing C-type lectin and butyrophilin genes for innate immunity and expression of antibacterial peptides. Multifluorescence in situ hybridization showed that alligator chromosome 3, which encodes DMRT1, exhibits significant synteny with chicken chromosome Z. Finally, population history analysis indicated population admixture 0.60-1.05 million years ago, when the Qinghai-Tibetan Plateau was uplifted.
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One-pot multistep cascade reactions over multifunctional nanocomposites with Pd nanoparticles supported on amine-modified mesoporous silica.
Chem Asian J
PUBLISHED: 04-15-2013
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Two kinds of multifunctional nanocomposites, SBA-15-NH2/Pd-p and SBA-15-NH2/Pd-f, with platelet-like and fiber-like morphologies, respectively, were fabricated by immobilizing Pd NPs onto amine-functionalized SBA-15. Some of the amino groups acted as anchoring sites for Pd NPs, whilst the remaining groups acted as Brønsted basic sites. As a result, the composites served as excellent multifunctional heterogeneous catalysts for one-pot multistep cascade reaction sequences. Moreover, when diffusion was the rate-determine step, SBA-15-NH2/Pd-p, with small mesopores, was superior to the fiber-like control sample, owing to its short diffusion length, a lower possibility of pore clogging, and better mass transportation for the reaction species during the catalysis.
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?-Fe2 O3 nanodisks: layered structure, growth mechanism, and enhanced photocatalytic property.
Chemistry
PUBLISHED: 04-06-2013
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Layered structure: ?-Fe2 O3 nanodisks with a layered structure assembled from nanoplates were produced by a hydrothermal method. The simple, low-cost method used silicate anions as capping ligands, which selectively adsorbed onto the {0001} facet of ?-Fe2 O3 and terminated the growth along the [0001] direction, leading to platelike building units. The layered structure led to significantly enhanced absorption of visible light, compared with single-layer ?-Fe2 O3 , and excellent photocatalytic abilities.
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Synthesis and chirality control of bulk crystals and nanocrystals: from a right-handed nonpolar chain to a left-handed polar chain.
Inorg Chem
PUBLISHED: 03-18-2013
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Both bulk crystals and nanocrystals of two helical complexes, [Cu(?2-L)(H2O)]n (1) and {[Cu(?2-L)(H2O)]·2H2O}n (2) (H2L = thiazolidine-2,4-dicarboxylic acid), have been synthesized with the chiralities of right-handedness (1) and left-handedness (2), respectively. 4-Cyanopyridine and poly(vinylpyrrolidone) (PVP) have been applied to control the synthesis of complexes with different helicities in bulk-crystal and nanocrystal forms, respectively. 2 can be irreversibly transformed to 1 under heating. Associated with the conformation changing, the symmetry alters between nonpolar and polar space groups.
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Au nanoparticles embedded into the inner wall of TiO2 hollow spheres as a nanoreactor with superb thermal stability.
Chem. Commun. (Camb.)
PUBLISHED: 03-07-2013
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A new nanoreactor-type composite catalyst with Au NPs embedded into the inner wall of the mesoporous TiO2 hollow spheres resulted in an enhanced synergistic effect and superb thermal stability of highly dispersed Au NPs.
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Berberine ameliorates chronic kidney injury caused by atherosclerotic renovascular disease through the suppression of NF?B signaling pathway in rats.
PLoS ONE
PUBLISHED: 02-19-2013
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Impaired renal function in atherosclerotic renovascular disease (ARD) may be the result of crosstalk between atherosclerotic renovascular stenosis and amplified oxidative stress, inflammation and fibrosis. Berberine (BBR) regulates cholesterol metabolism and exerts antioxidant effects. Accordingly, we hypothesized that BBR treatment may ameliorate ARD-induced kidney injury through its cholesterol-lowering effect and also suppression of the pathways involved in oxidative stress, inflammation and NF?B activation.
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A yolk-shell structured Fe2O3@mesoporous SiO2 nanoreactor for enhanced activity as a Fenton catalyst in total oxidation of dyes.
Chem. Commun. (Camb.)
PUBLISHED: 02-14-2013
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Through a simple polymeric carbon assisted method, a yolk-shell structured Fe(2)O(3)@mesoporous SiO(2) nanoreactor was synthesized and showed excellent activity in Fenton-like reactions toward methylene blue total degradation.
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Genome of the Chinese tree shrew.
Nat Commun
PUBLISHED: 02-07-2013
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Chinese tree shrews (Tupaia belangeri chinensis) possess many features valuable in animals used as experimental models in biomedical research. Currently, there are numerous attempts to employ tree shrews as models for a variety of human disorders: depression, myopia, hepatitis B and C virus infections, and hepatocellular carcinoma, to name a few. Here we present a publicly available annotated genome sequence for the Chinese tree shrew. Phylogenomic analysis of the tree shrew and other mammalians highly support its close affinity to primates. By characterizing key factors and signalling pathways in nervous and immune systems, we demonstrate that tree shrews possess both shared common and unique features, and provide a genetic basis for the use of this animal as a potential model for biomedical research.
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Dual modes of antitumor action of an amphiphilic peptide A(9)K.
Biomaterials
PUBLISHED: 01-23-2013
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Following our recent report of attractive antibacterial properties of a designed amphiphilic peptide, A(9)K, we have investigated its antitumor activities by examining the modes of its action against different mammalian cell types. The peptide strongly inhibited the growth of cancerous HeLa cells and human promyelocytic leukemia HL60 cells whilst remaining benign to the host cells, including Cos 7 cells, mouse fibroblast NIH3T3 cells and human red blood cells. Images from SEM and fluorescence microscopy showed that A(9)K penetrated HeLa cell membranes and disrupted membrane structures, a feature broadly similar to that observed from its bactericidal actions. Further interactions of A(9)K with inner cellular membranes caused mitochondrial dysfunction associated with the F-actin reorganization and the decreased transcription of bcl-2 and c-myc genes, resulting in HeLa cell apoptosis in a mitochondria-induced apoptosis pathway. Thus A(9)K has high selectivity against cancerous cells and kills them by dual modes of action: membrane disruption and cell apoptosis. In addition, the peptide does not induce non-specific immunological effects and is not degraded by proteases. These features are crucial for developing their applications in future research.
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Pregnancy and iron homeostasis: an update.
Nutr. Rev.
PUBLISHED: 01-04-2013
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It has been nearly 15 years since the first review on pregnancy and iron deficiency was published in Nutrition Reviews. Many unresolved issues raised in that seminal review have been addressed. New proteins involved in nonheme and heme iron transport have been identified in the enterocyte, and information on the roles of these proteins in the placenta is evolving. The systemic iron regulatory hormone, hepcidin, has since been identified as a key regulator of iron homeostasis. Additional data on the efficacy and consequences of prenatal iron supplementation are available. Emerging data on developmental changes in iron absorption across early infancy have further emphasized the need to ensure that the iron endowment of the neonate at birth is optimal. This is especially important, given growing evidence linking neonatal iron status with subsequent cognitive and neurobehavioral outcomes. Along with the many advances, new questions and gaps in knowledge have been identified. This review summarizes new data on maternal iron utilization across pregnancy as it impacts the pregnant woman and the iron status of the neonate at birth.
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Temperature-directed structural recurrence in low-symmetric Co(II) complexes and nanocrystals.
Chem. Commun. (Camb.)
PUBLISHED: 12-01-2011
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Low-symmetric complexes {[Co(?(2)-L)(H(2)O)(2)]·H(2)O}(n) (1) and {[Co(?(3)-L)(H(2)O)]·0.5H(2)O}(n) (2) and corresponding nanocrystals were obtained, which exhibit structural recurrence behaviour at various temperatures as well as changes of chiral, nonlinear optical and ferroelectric properties.
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Calibrating the end-Permian mass extinction.
Science
PUBLISHED: 11-17-2011
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The end-Permian mass extinction was the most severe biodiversity crisis in Earth history. To better constrain the timing, and ultimately the causes of this event, we collected a suite of geochronologic, isotopic, and biostratigraphic data on several well-preserved sedimentary sections in South China. High-precision U-Pb dating reveals that the extinction peak occurred just before 252.28 ± 0.08 million years ago, after a decline of 2 per mil (‰) in ?(13)C over 90,000 years, and coincided with a ?(13)C excursion of -5‰ that is estimated to have lasted ?20,000 years. The extinction interval was less than 200,000 years and synchronous in marine and terrestrial realms; associated charcoal-rich and soot-bearing layers indicate widespread wildfires on land. A massive release of thermogenic carbon dioxide and/or methane may have caused the catastrophic extinction.
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[Clinical analysis of 8 cases of hepatitis-associated aplastic anemia].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 08-27-2011
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To study the clinical characteristics of hepatitis-associated aplastic anemia (HAAA). A retrospective analysis was conducted among 8 cases of established HAAA in light of the clinical and laboratory findings and the patient outcomes.
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[The research of saffold virus in children with lower respiratory tract infection in Changsha].
Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi
PUBLISHED: 07-28-2011
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To investigate prevalence of Saffold virus (SAFV) in Changsha area of hospitalized children with respiratory tract infection, and to discuss whether this virus is related to respiratory tract infection of children.
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[Detection and clinical characteristics analysis of human bocavirus 1-3 in children for acute respiratory infection in Lanzhou area].
Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi
PUBLISHED: 07-28-2011
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To study the clinical and molecular epidemiology characteristics of human Bocavirus 1-3 (HBoV1-3) in children for acute respiratory infection in Lanzhou area.
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Absence of association between GSTM1 and GSTT1 polymorphisms and melanoma susceptibility: a meta-analysis.
DNA Cell Biol.
PUBLISHED: 05-12-2011
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Glutathione S-transferases (GSTs) are a family of multifunctional enzymes that are involved in the metabolism of many xenobiotics, including a wide range of environmental carcinogens. The null genotypes GSTM1 and GSTT1 have been implicated in the development of carcinogenesis. We conducted a meta-analysis to examine the association of GSTM1 and GSTT1 homozygous deletion polymorphisms with melanoma risk. In total, 8 relevant studies were identified in searches of the PubMed and Embase databases: 8 investigated GSTM1 (1349 cases and 1560 controls) and 5 GSTT1 (977 cases and 1060 controls). Fixed- and random-effects models were used to assess the summary odds ratios (ORs). No significant association of the GSTM1 and GSTT1 polymorphisms or the GSTM1-GSTT1 interaction on the risk of melanoma was observed (for GSTM1: OR=1.09; 95% confidence interval, 0.94-1.27; and for GSTT1: OR=0.95; 95% confidence interval, 0.76-1.19). Similarly, no significant association was found in a subgroup analysis of hair color. These results indicate that the GSTM1 and GSTT1 polymorphisms may not be a risk factor for developing melanoma.
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Superb fluoride and arsenic removal performance of highly ordered mesoporous aluminas.
J. Hazard. Mater.
PUBLISHED: 02-16-2011
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Highly ordered mesoporous aluminas and calcium-doped aluminas were synthesized through a facile and reproducible method. Their fluoride adsorption characteristics, including adsorption isotherms, adsorption kinetics, the effect of pH and co-existing anions were investigated. These materials exhibited strong affinity to fluoride ions and extremely high defluoridation capacities. The highest defluoridation capacity value reached 450 mg/g. These materials also showed superb arsenic removal ability. 1g of mesoporous alumina was able to treat 200 kg of arsenic contaminated water with a pH value of 7, reducing the concentration of arsenate from 100 ppb to 1 ppb.
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Neuropathic Nav1.3-mediated sensitization to P2X activation is regulated by protein kinase C.
Mol Pain
PUBLISHED: 02-11-2011
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Increased neuronal excitability and spontaneous firing are hallmark characteristics of injured sensory neurons. Changes in expression of various voltage-gated Na+ channels (VGSCs) have been observed under neuropathic conditions and there is evidence for the involvement of protein kinase C (PKC) in sensory hyperexcitability. Here we demonstrate the contribution of PKC to P2X-evoked VGSC activation in dorsal root ganglion (DRG) neurons in neuropathic conditions.
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Fabrication of nanostructured metal nitrides with tailored composition and morphology.
Chem. Commun. (Camb.)
PUBLISHED: 02-03-2011
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Unprecedented multi-channel TiN micro/nanotubes as well as various metal nitride nanofibers, including TiN, VN, NbN and ternary metal nitride nanofibers, were fabricated by a template free electrospinning method combined with post-nitridation.
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Biochemical characterization and in vitro activity of AZ513, a noncovalent, reversible, and noncompetitive inhibitor of fatty acid amide hydrolase.
Eur. J. Pharmacol.
PUBLISHED: 01-30-2011
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Fatty acid amide hydrolase (FAAH) hydrolyzes several bioactive lipids including the endocannabinoid anandamide. Synthetic FAAH inhibitors are being generated to help define the biological role(s) of this enzyme, the lipids it degrades in vivo, and the disease states that might benefit from its pharmacological modulation. AZ513 inhibits human FAAH (IC(50)=551 nM), is 20-fold more potent against rat FAAH (IC(50)=27 nM), and is inactive at 10 ?M against the serine hydrolases acetylcholinesterase, thrombin, and trypsin. In contrast to most other potent FAAH inhibitors, AZ513 showed no evidence of covalently modifying the enzyme and displayed reversible inhibition. In an enzyme cross-competition assay, AZ513 did not compete with OL-135, an inhibitor that binds to the catalytic site in FAAH, which indicates that AZ513 does not bind to the catalytic site and is therefore noncompetitive with respect to substrate. AZ513 has good cell penetration as demonstrated by inhibition of anandamide hydrolysis in human FAAH-transfected HEK293 cells (IC(50)=360 nM). AZ513 was tested in a rat spinal cord slice preparation where CB(1) activation reduces excitatory post-synaptic currents (EPSCs). In this native tissue assay of synaptic activity, AZ513 reduced EPSCs, which is consistent with inhibiting endogenous FAAH and augmenting endocannabinoid tone. AZ513 has a unique biochemical profile compared with other published FAAH inhibitors and will be a useful tool compound to further explore the role of FAAH in various biological processes.
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Synthesis of biomimetic poly[2-(methacryloyloxy)ethyl phosphorycholine]-coated magnetite nanoparticles via surface-initiated atom transfer radical polymerization.
J Nanosci Nanotechnol
PUBLISHED: 01-22-2011
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Modification of magnetite nanoparticles with biomimetic poly[2-(methacryloyloxy)ethyl phosphorycholine] (poly(MPC)) via surface-initiated atom transfer radical polymerization (ATRP) was carried out. Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analyses (TGA) and zeta potential studies indicated that well defined poly (MPC) was successfully grafted on the surface of magnetite nanoparticles. X-ray diffraction results showed the structure of magnetite nanoparticles after surface modification was not changed. The poly (MPC)-coated magnetite nanoparticles had a mean transmission electron microscopy (TEM) diameter of 11 +/- 1.5 nm. The resulting nanomaterials were superparamagnetic at room temperature, exhibited good colloidal stability in aqueous media and good responsibility to magnetic field. Such magnetite nanoparticles with biomimetic surface have potential application in prolonging circulation time in vivo.
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Effect of varying the length of soft-tissue grafts in the tibial tunnel in a canine anterior cruciate ligament reconstruction model.
Arthroscopy
PUBLISHED: 01-11-2011
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To investigate the effect of graft length within the bone tunnel on tendon-bone healing at an early stage after anterior cruciate ligament (ACL) reconstruction using Achilles tendon autograft in a canine model.
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Double fixation of displaced patella fractures using bioabsorbable cannulated lag screws and braided polyester suture tension bands.
Injury
PUBLISHED: 01-05-2011
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To evaluate the effectiveness and safety of a new double fixation technique for displaced patellar fractures using bioabsorbable cannulated lag screws and braided polyester suture tension bands.
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Bidirectional regulation of neurogenesis by neuronal nitric oxide synthase derived from neurons and neural stem cells.
Stem Cells
PUBLISHED: 09-17-2010
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It has been demonstrated that neuronal nitric oxide synthase (nNOS) negatively regulates adult neurogenesis. However, the cellular and molecular mechanisms underlying are poorly understood. Here, we show that nNOS from neural stem cells (NSCs) and from neurons play opposite role in regulating neurogenesis. The NSCs treated with nNOS inhibitor N(5)-(1-imino-3-butenyl)-L- ornithine (L-VNIO) or nNOS gene deletion exhibited significantly decreased proliferation and neuronal differentiation, indicating that NSCs-derived nNOS is essential for neurogenesis. The NSCs cocultured with neurons displayed a significantly decreased proliferation, and deleting nNOS gene in neurons or scavenging extracellular nitric oxide (NO) abolished the effects of coculture, suggesting that neurons-derived nNOS, a source of exogenous NO for NSCs, exerts a negative control on neurogenesis. Indeed, the NSCs exposed to NO donor DETA/NONOate displayed decreased proliferation and neuronal differentiation. The bidirectional regulation of neurogenesis by NSCs- and neurons-derived nNOS is probably related to their distinct subcellular localizations, mainly in nuclei for NSCs and in cytoplasm for neurons. Both L-VNIO and DETA/NONOate inhibited telomerase activity and proliferation in wild-type (WT) but not in nNOS(-/-) NSCs, suggesting a nNOS-telomerase signaling in neurogenesis. The NSCs exposed to DETA/NONOate exhibited reduced cAMP response element binding protein (CREB) phosphorylation, nNOS expression, and proliferation. The effects of DETA/NONOate were reversed by forskolin, an activator of CREB signaling. Moreover, disrupting CREB phosphorylation by H-89 or LV-CREB133-GFP simulated the effects of DETA/NONOate, and inhibited telomerase activity. Thus, we conclude that NSCs-derived nNOS stimulates neurogenesis via activating telomerase, whereas neurons-derived nNOS represses neurogenesis by supplying exogenous NO that hinders CREB activation, in turn, reduces nNOS expression in NSCs.
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Blocking spinal CCR2 with AZ889 reversed hyperalgesia in a model of neuropathic pain.
Mol Pain
PUBLISHED: 04-09-2010
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The CCR2/CCL2 system has been identified as a regulator in the pathogenesis of neuropathy-induced pain. However, CCR2 target validation in analgesia and the mechanism underlying antinociception produced by CCR2 antagonists remains poorly understood. In this study, in vitro and in vivo pharmacological approaches using a novel CCR2 antagonist, AZ889, strengthened the hypothesis of a CCR2 contribution to neuropathic pain and provided confidence over the possibilities to treat neuropathic pain with CCR2 antagonists.
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Adrenomedullin ameliorates the development of atherosclerosis in apoE-/- mice.
Peptides
PUBLISHED: 03-09-2010
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Adrenomedullin (ADM) is a multifunctional peptide regulating cardiovascular homeostasis. We studied the role of ADM in the pathogenesis of atherosclerosis by investigating changes in ADM and its receptors - calcitonin receptor-like receptor (CRLR) and receptor activity-modifying proteins (RAMPs) - in aorta of apoE-/- mice and the effect of exogenous ADM administration. ApoE-/- mice were fed an atherogenic diet for 4 weeks, and apoE-/-+ADM mice were additionally given subcutaneous injections of ADM, 300ng/kg/h, for 4 weeks. ApoE-/- mice fed an atherogenic diet showed hyperlipidemia, a large plaque area and increased vessel wall thickness. The mRNA expression and protein level of ADM/ADM receptors were increased in the aorta, compared with C57BL/6J mice. The elevated mRNA level of CRLR and RAMPs correlated positively with ADM mRNA level. Radioimmunoassay revealed a higher plasma and aorta ADM content, by 61.6% and 285% (both P<0.01), respectively, in apoE-/- mice than that in C57BL/6J mice. Exogenous ADM significantly ameliorated dyslipidemia in apoE-/- mice. ADM-treated mice showed fewer aortic plaques, decreased plaque area, by 76% (P<0.01), and reduced ratio of plaque area to luminal area, by 65% (P<0.01), and ultrasonography revealed significantly reduced intima-media thickness of the ascending branch and abdominal aorta. The results suggest that atherosclerotic apoE-/- mice fed an atherogenic diet showed upregulated endogenous ADM and its receptors, and exogenous ADM treatment ameliorated the dyslipidemia and vascular atherosclerotic lesions. ADM/ADM receptors might be an important protective system against atherosclerosis and could become a new target of prevention and therapy for atherosclerosis.
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The potent adjuvant effects of chicken beta-defensin-1 when genetically fused with infectious bursal disease virus VP2 gene.
Vet. Immunol. Immunopathol.
PUBLISHED: 01-27-2010
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Defensins are fundamental components of innate immune response. Current data favor that defensins play vital roles on both innate and adaptive immune responses. The aim of the present study was to investigate whether the chicken beta-defensin-1 (also named avian beta-defensin-1, AvBD1) has the potent adjuvant effects on DNA vaccine encoding IBDV VP2 gene, when genetically fused with VP2 gene. The recombinant vectors pcDNA3.1(+)-VP2 and pcDNA3.1(+)-AvBD1-VP2 were constructed as the DNA vaccines. Four groups of 14-day-old chickens were intramuscularly injected with PBS buffer, empty vector pcDNA3.1(+), recombinant pcDNA3.1(+)-VP2 and pcDNA3.1(+)-AvBD1-VP2. Results showed that VP2-specific antibody levels significantly increased following two recombinant DNA vaccine administrations (p<0.05), compared with the group of PBS and empty vector. The antibody level of group immunized with pcDNA3.1(+)-AvBD1-VP2 was significantly higher than that of group immunized with pcDNA3.1(+)-VP2 after second vaccination (p<0.05). The percentages of CD3+, CD4+ and CD8+ T-cell subtypes between groups of pcDNA3.1(+)-VP2 and pcDNA3.1(+)-AvBD1-VP2 obtained significantly different (p<0.05), the latter was higher, at 7 days post-booster. The protection from IBD challenged by immunized chickens with DNA vaccines encoding IBDV VP2 gene alone was lower than that by immunized IBDV VP2 gene together with AvBD1 gene. The results indicated that AvBD1 has an adjuvant effects on improvement the IBDV VP2-DNA vaccine effectiveness.
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A peripherally restricted cannabinoid receptor agonist produces robust anti-nociceptive effects in rodent models of inflammatory and neuropathic pain.
Pain
PUBLISHED: 01-25-2010
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Cannabinoids are analgesic in man, but their use is limited by their psychoactive properties. One way to avoid cannabinoid receptor subtype 1 (CB1R)-mediated central side-effects is to develop CB1R agonists with limited CNS penetration. Activation of peripheral CB1Rs has been proposed to be analgesic, but the relative contribution of peripheral CB1Rs to the analgesic effects of systemic cannabinoids remains unclear. Here we addressed this by exploring the analgesic properties and site of action of AZ11713908, a peripherally restricted CB1R agonist, in rodent pain models. Systemic administration of AZ11713908 produced robust efficacy in rat pain models, comparable to that produced by WIN 55, 212-2, a CNS-penetrant, mixed CB1R and CB2R agonist, but AZ11713908 generated fewer CNS side-effects than WIN 55, 212-in a rat Irwin test. Since AZ11713908 is also a CB2R inverse agonist in rat and a partial CB2R agonist in mouse, we tested the specificity of the effects in CB1R and CB2R knock-out (KO) mice. Analgesic effects produced by AZ11713908 in wild-type mice with Freunds complete adjuvant-induced inflammation of the tail were completely absent in CB1R KO mice, but fully preserved in CB2R KO mice. An in vivo electrophysiological assay showed that the major site of action of AZ11713908 was peripheral. Similarly, intraplantar AZ11713908 was also sufficient to induce robust analgesia. These results demonstrate that systemic administration of AZ11713908, produced robust analgesia in rodent pain models via peripheral CB1R. Peripherally restricted CB1R agonists provide an interesting novel approach to analgesic therapy for chronic pain.
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Rapid detection of infectious laryngotracheitis virus isolates by loop-mediated isothermal amplification.
J. Virol. Methods
PUBLISHED: 01-18-2010
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The objective of this study was to develop and evaluate a loop-mediated isothermal amplification (LAMP) method to detect infectious laryngotracheitis virus (ILTV) from commercial broiler and layer flocks in southern China. A set of six specific primers was designed to recognize six distinct genomic sequences of thymidine kinase (TK) from ILTV. The entire assay duration was recorded at 40 min under isothermal condition at 63.5 degrees C. The amplified products were analyzed by electrophoresis and visual judgment by the SYBR Green I dyeing. LAMP assay was 10-fold more sensitive than the routine PCR assay, with a detection limit of 46 copies per reaction. In detecting ILTV, the LAMP assay detected all 5 strains previously isolated, did not cross-react with other avian pathogens, and obtained a 100% sensitivity in 43 positive clinical samples with reference to virus isolation. Therefore, the LAMP assay may be a good alternative method for specific diagnosis of ILTV infection in primary care facilities, and in less well-equipped laboratories.
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Apple sucrose transporter SUT1 and sorbitol transporter SOT6 interact with cytochrome b5 to regulate their affinity for substrate sugars.
Plant Physiol.
PUBLISHED: 06-05-2009
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Sugar transporters are central machineries to mediate cross-membrane transport of sugars into the cells, and sugar availability may serve as a signal to regulate the sugar transporters. However, the mechanisms of sugar transport regulation by signal sugar availability remain unclear in plant and animal cells. Here, we report that a sucrose transporter, MdSUT1, and a sorbitol transporter, MdSOT6, both localized to plasma membrane, were identified from apple (Malus domestica) fruit. Using a combination of the split-ubiquitin yeast two-hybrid, immunocoprecipitation, and bimolecular fluorescence complementation assays, the two distinct sugar transporters were shown to interact physically with an apple endoplasmic reticulum-anchored cytochrome b5 MdCYB5 in vitro and in vivo. In the yeast systems, the two different interaction complexes function to up-regulate the affinity of the sugar transporters, allowing cells to adapt to sugar starvation. An Arabidopsis (Arabidopsis thaliana) homolog of MdCYB5, AtCYB5-A, also interacts with the two sugar transporters and functions similarly. The point mutations leucine-73 --> proline in MdSUT1 and leucine-117 --> proline in MdSOT6, disrupting the bimolecular interactions but without significantly affecting the transporter activities, abolish the stimulating effects of the sugar transporter-cytochrome b5 complex on the affinity of the sugar transporters. However, the yeast (Saccharomyces cerevisiae) cytochrome b5 ScCYB5, an additional interacting partner of the two plant sugar transporters, has no function in the regulation of the sugar transporters, indicating that the observed biological functions in the yeast systems are specific to plant cytochrome b5s. These findings suggest a novel mechanism by which the plant cells tailor sugar uptake to the surrounding sugar availability.
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Subtype-specific regulation of P2X3 and P2X2/3 receptors by phosphoinositides in peripheral nociceptors.
Mol Pain
PUBLISHED: 05-21-2009
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P2X3 and P2X2/3 purinergic receptor-channels, expressed in primary sensory neurons that mediate nociception, have been implicated in neuropathic and inflammatory pain responses. The phospholipids phosphatidylinositol 4,5-bisphosphate (PIP2) and phosphatidylinositol 3,4,5-trisphosphate (PIP3) are involved in functional modulation of several types of ion channels. We report here evidence that these phospholipids are able to modulate the function of homomeric P2X3 and heteromeric P2X2/3 purinoceptors expressed in dorsal root ganglion (DRG) nociceptors and in heterologous expression systems.
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Discovery and pharmacological characterization of a small-molecule antagonist at neuromedin U receptor NMUR2.
J. Pharmacol. Exp. Ther.
PUBLISHED: 04-15-2009
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Neuromedin U (NMU), through its cognate receptor NMUR2 in the central nervous system, regulates several important physiological functions, including energy balance, stress response, and nociception. By random screening of our corporate compound collection with a ligand binding assay, we discovered (R)-5-(phenylaminocarbonylamino)spiro[1-azabicyclo[2.2.2]octane-3,2(3H)-furo[2,3-b]pyridine] (R-PSOP), a highly potent and selective NMUR2 antagonist. R-PSOP is a nonpeptidic small-molecule with the chemical composition C(20)N(4)O(2)H(22). In competition binding experiments, this compound was found to bind to NMUR2 with high affinity; the K(i) values were determined to be 52 and 32 nM for the human and rat NMUR2, respectively. Moreover, in functional assays measuring phosphoinositide turnover or intracellular calcium mobilization, R-PSOP strongly inhibited the responses stimulated by peptide agonists NMU-25, NMU-23, and NMU-8 in human embryonic kidney 293 cells expressing NMUR2. From Schild analyses, the functional K(b) values for R-PSOP were determined to be 92 and 155 nM at human and rat NMUR2, respectively. Highly selective for NMUR2, R-PSOP exhibited low affinity to the other subtype of NMU receptor, NMUR1, with a K(i) value >10 microM. R-PSOP in vivo attenuated NMU-23-evoked nociceptive responses in a rat spinal reflex preparation. To our knowledge, this is the first antagonist ever reported for NMU receptors. This compound could serve as a valuable tool for further understanding the physiological and pathophysiological roles of NMU system, while providing a chemical starting point that may lead to development of new therapeutics for treatment of eating disorders, obesity, pain, and stress-related disorders.
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Rapid detection of porcine reproductive and respiratory syndrome virus by reverse transcription loop-mediated isothermal amplification assay.
J. Virol. Methods
PUBLISHED: 03-18-2009
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A rapid detection assay based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) has been developed for detecting porcine reproductive and respiratory syndrome virus (PRRSV). The RT-LAMP assay utilized a set of six primers to amplify the open reading frame 6 (ORF6) of the PRRSV. The amplified products were analyzed by agarose gel electrophoresis or visualized by colorimetric method. The results demonstrated that the RT-LAMP assay detected all 22 different PRRSV isolates, had no cross-reaction with four other swine viruses (i.e., PCV2, SIV, CSFV, and PEDV), and obtained a 91.3% sensitivity in 23 positive clinical samples in reference to the permissive cells-based virus isolation procedure. Therefore, the RT-LAMP assay provides a specific and sensitive means for detecting PRRSV in a simple, fast, and cost-effective manner. Furthermore, the RT-LAMP assay can be performed in less well-equipped laboratories as well as fields.
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Ubiquitous distribution and different subcellular localization of sorbitol dehydrogenase in fruit and leaf of apple.
J. Exp. Bot.
PUBLISHED: 01-27-2009
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NAD(+)-dependent sorbitol dehydrogenase (NAD-SDH, EC 1.1.1.14), a key enzyme in sorbitol metabolism, plays an important role in regulating sink strength and determining the quality of apple fruit. Understanding the tissue and subcellular localization of NAD-SDH is helpful for understanding sorbitol metabolism in the apple. In this study, two NAD-SDH cDNA sequences were isolated from apple fruits (Malus domestica Borkh cv. Starkrimson) and named MdSDH5 and MdSDH6. Immunohistochemical analysis revealed that NAD-SDH is distributed in both the flesh and the vascular tissue of the fruit, and the vascular tissue and mesophyll tissue in the young and old leaves, indicating that it is a ubiquitous protein expressed in both sink and source organs. Immunogold electron microscopy analysis demonstrated that NAD-SDH is localized mainly in the cytoplasm and chloroplast of the fruit and leaves. The chloroplast localization of NAD-SDH was confirmed by the transient expression of MdSDH5-GFP and MdSDH6-GFP in the mesophyll protoplast of Arabidopsis. NAD-SDH was also found in electron opaque deposits of vacuoles in young and mature leaves. These data show that NAD-SDH has different subcellular localizations in fruit and leaves, indicating that it might play a different role in sorbitol metabolism in different tissues of apple.
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Biphenyl-3,3,4,4-tetra-carboxylic acid dihydrate.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 01-08-2009
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The asymmetric unit of the title compound, C(16)H(10)O(8)·2H(2)O, contains one-half of the centrosymmetric organic mol-ecule and one water mol-ecule. The dihedral angles between the carboxyl-ate groups and the adjacent phenyl ring are 71.31?(3) and 16.67?(3)°, while the carboxyl-ate groups are oriented at a dihedral angle of 72.01?(3)°. In the crystal structure, inter-molecular O-H?O and bifurcated O-H?(O,O) hydrogen bonds link the mol-ecules to form a three-dimensional supra-molecular network.
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Rapid diagnosis of duck plagues virus infection by loop-mediated isothermal amplification.
Res. Vet. Sci.
PUBLISHED: 01-02-2009
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Duck virus enteritis is a serious disease among farmed and free-living ducks (Anatidae) and a constant threat to the commercial duck industry in China. In this study, a loop-mediated isothermal amplification (LAMP) assay was developed to rapidly detect and diagnose duck plague virus (DPV) in both farmed and wild waterfowl, and compared with polymerase chain reaction (PCR) method and real-time PCR method in accuracy, sensitivity and specificity. A set of four specific primers was successfully designed to recognize six distinct genomic sequences of UL6 protein from DPV, including one forward inner primer, one back inner primer and two outer primers. The optimum reaction temperature and time were verified to be 61.5 degrees C and 60 min, respectively. Comparative experiments showed that LAMP assay was a simple, rapid, accurate, sensitive and specific method for detecting DPV, and was superior to PCR assay in sensitivity and specificity for DNA amplification. In addition, challenge tests indicated the newly developed LAMP method was more sensitive for the diagnosis of DPV infection than virus isolation and PCR. LAMP assay would be a good alternative method for on-farm disease diagnosis.
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Dynamic distribution and tissue tropism of infectious laryngotracheitis virus in experimentally infected chickens.
Arch. Virol.
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Infectious laryngotracheitis (ILT), caused by infectious laryngotracheitis virus (ILTV), is an Office International des Epizooties (OIE) notifiable disease. However, we have not clearly understood the dynamic distribution, tissue tropism, pathogenesis, and replication of ILTV in chickens. In this report, we investigated the dynamic distribution and tissue tropism of the virus in internal organs of experimentally infected chickens using quantitative real-time polymerase chain reaction (qPCR) and a histopathological test. The study showed that ILTV could be clearly detected in eight internal organs (throat, trachea, lung, cecum, kidney, pancreas, thymus and esophagus) of infected chickens, whereas the virus was difficult to detect in heart, spleen, proventriculus, liver, brain and bursa. Meanwhile, the thymidine kinase (TK) gene levels in eight internal organs increased from 3 days to 5 days postinfection, and then decreased from 6 days to 8 days postinfection. The log copy number of ILTV progressively increased over 3 days, which corresponds to the clinical score and the result of the histopathological test. The results provide a foundation for further clarification of the pathogenic mechanism of ILTV in internal organs and indicate that throat, lung, trachea, cecum, kidney, pancreas and esophagus may be preferred sites of acute infection, suggesting that the tissue tropism and distribution of ILTV is very broad.
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Control of P2X3 channel function by metabotropic P2Y2 utp receptors in primary sensory neurons.
Mol. Pharmacol.
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Purinergic signaling contributes significantly to pain mechanisms, and the nociceptor-specific P2X3 ATP receptor channel is considered a target in pain therapeutics. Recent findings suggesting the coexpression of metabotropic P2Y receptors with P2X3 implies that ATP release triggers the activation of both ionotropic and metabotropic purinoceptors, with strong potential for functional interaction. Modulation of native P2X3 function by P2Y receptor activation was investigated in rat dorsal root ganglia (DRG) neurons using whole cell patch-clamp recordings. Application of the selective P2Y receptor agonist UTP decreased peak amplitudes of ?,?-meATP-evoked homomeric P2X3-mediated currents, but had no effect on heteromeric P2X2/3-mediated currents. Treatment with phospholipase C inhibitor U73122 significantly reversed P2X3 current inhibition induced by UTP-sensitive P2Y receptor activation. We previously reported the modulation of P2X receptors by phospholipids in DRG neurons and injection of exogenous phosphatidylinositol-4,5-bisphosphate (PIP(2)) fully reverses UTP-mediated regulation of P2X3 channel activity. Pharmacological as well as functional screening of P2Y receptor subtypes indicates the predominant involvement of P2Y2 receptor in P2X3 inhibition, and immunolocalization confirms a significant cellular coexpression of P2X3 and P2Y2 in rat DRG neurons. In summary, the function of P2X3 ATP receptor can be inhibited by P2Y2-mediated depletion of PIP(2). We propose that expression of P2Y2 purinoceptor in nociceptive sensory neurons provides an homeostatic mechanism to prevent excessive ATP signaling through P2X3 receptor channels.
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Functional genomics of the rat neuromedin U receptor 1 reveals a naturally occurring deleterious allele.
Physiol. Genomics
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Neuromedin U (NMU) plays an important role in a number of physiological processes, but the relative contribution of its two known receptors, NMUR1 and NMUR2, is still poorly understood. Here we report the existence of a SNP T(1022)?A (Val(341)?Glu) in the third exon of the rat Nmur1 gene that leads to an inactive receptor. This SNP is present within the coding region of the highly conserved NPXXY motif found within all class A type G protein-coupled receptors and translates to an NMUR1 receptor that is not expressed on the cell surface. Genetic analysis of the Nmur1 gene in a population of Sprague-Dawley rats revealed that this strain is highly heterogeneous for the inactivating polymorphism. The loss of functional NMUR1 receptors in Sprague-Dawley rats homozygous for the inactive allele was confirmed by radioligand binding studies on native tissue expressing NMUR1. The physiological relevance of this functional genomics finding was examined in two nociceptive response models. The pronociceptive effects of NMU were abolished in rats lacking functional NMUR1 receptors. The existence of naturally occurring NMUR1-deficient rats provides a novel and powerful tool to investigate the physiological role of NMU and its receptors. Furthermore, it highlights the importance of verifying the NMUR1 single nucleotide polymorphism status for rats used in physiological, pharmacological or toxicological studies conducted with NMUR1 modulators.
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Qualified kidney biomarkers and their potential significance in drug safety evaluation and prediction.
Pharmacol. Ther.
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The kidney is one of the major organs drug toxicity may target. Some renal safety biomarkers have been proposed to measure kidney injury and function accordingly. Despite the widespread use for diagnosis and monitoring of renal injury and function for decades, serum creatinine and blood urea nitrogen are nonspecific biomarkers with insensitive and delayed response in the clinical setting. There is an urgent need to identify and qualify novel kidney safety biomarkers that would be used to detect and predict drug-induced nephrotoxicity in preclinical toxicological studies, clinical trials and patient care in sequence. To do that, eight novel renal safety biomarkers have been well characterized and qualified for preclinical drug safety screening, and their clinical bridging validation is underway as well. Of them, some are used to detect or predict proximal tubular injury, and others are used to diagnose and monitor glomerular damage. Thus, measurement of a panel of kidney safety biomarkers in parallel would help maximally capture all potential safety signals for a more informative decision to be made in drug research and development as well as for optimal selection of the drug and its dose in clinical practice.
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Synthesis, self-assembly, and high performance in gas sensing of X-shaped iron oxide crystals.
ACS Appl Mater Interfaces
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X-shaped goethite iron oxide crystals were synthesized by a surfactant-free mild hydrothermal synthesis method with the aid of fluorine ions. The X-shaped goethite crystals could readily self-assemble into microscopic hollow spheres through an oil-water interface induced self-assembly method. X-shaped hematite crystals were obtained by phase topotactic transformation of the goethite precursors. The gas sensor properties of X-shaped hematite iron oxide were investigated, and the mechanism for excellent sensor properties was discussed.
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[Molecular epidemiological and clinical feature of human metapneumovirus in children with acute lower respiratory tract infection in Changsha area from 2007 to 2011].
Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi
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To understand the epidemiological characteristics of human metapneumovirus (hMPV) infection in children with acute lower respiratory tract infection (ALRTI) in Changsha area, China.
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Core-shell structured mesoporous silica as acid-base bifunctional catalyst with designated diffusion path for cascade reaction sequences.
Chem. Commun. (Camb.)
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A core-shell structured mesoporous silica nanosphere with antagonistic acid and basic sites spatially isolated and designated diffusion path was fabricated and served as an efficient acid-base bifunctional catalyst for one-pot cascade reaction sequences with excellent activity and selectivity.
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[Ecosystem service interactions and their affecting factors in Jinghe watershed at county level].
Ying Yong Sheng Tai Xue Bao
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Taking the multiple ecosystem services (grain supply, meat supply, fuel-wood supply, water resource conservation and soil retention) as test objects, this paper analyzed the interactions among these services, the interaction modes and the possible affecting factors in 31 counties of Jinghe watershed. At the county level, there existed great differences in the interactions among different pairs of the ecosystem services. The grain supply showed significant positive correlation with meat supply but negative correlation with soil retention, whereas the water resource conservation showed significant positive correlations with fuel-wood supply and soil retention. As for the interaction modes of the ecosystem services, 24 counties were primarily of regulation services, 3 counties were of supply and regulation services in balance, and 4 counties were primarily of grain supply. The total ecosystem service index of the interaction modes in each county varied greatly, with 5.1 times of difference between the maximum (Jingyuan County) and the minimum value (Yanchi County). The total ecosystem service index was significantly positively correlated with precipitation and soil total nitrogen, and negatively correlated with solar hours. The increase of farmland had negative effects, while that of shrub land and grassland had great positive effects on the total ecosystem service index, but the increase of forestland had less effects.
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Fe3+ and amino functioned mesoporous silica: preparation, structural analysis and arsenic adsorption.
J. Hazard. Mater.
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Two novel adsorbents to remove excess arsenate and arsenite in the drinking water were prepared for the first time by grafting monoamine and diamine, respectively, and then coordinating Fe(3+) on silica gel that was obtained using sol-gel method with two-step acid-base catalysis. It was found that both adsorbents had mesoporous structure, large specific surface, and high amino and iron content according to N(2) adsorption isotherms, FTIR, XPS, and NMR analysis. The removal ability and adsorption rate of the adsorbents were very high for both As(V) and As(III). Langmuir and Freundlich models were used to fit the adsorption isotherm and investigate the adsorption mechanism. The effects of chloride and sulfate anion on the removal of arsenate and arsenite for the two adsorbents were also studied.
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Differential expression and pharmacology of native P2X receptors in rat and primate sensory neurons.
J. Neurosci.
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Evidence suggesting the involvement of P2X2 and P2X3 in chronic pain has been obtained mostly from rodent models. Here we show that rodents may be poor predictors of P2X3 pharmacology in human. We demonstrate that monkey and human dorsal root ganglion (DRG) neurons do not express appreciable levels of P2X2 subunit, contrary to rat sensory neurons. Additionally, we report functional P2X3 activity in monkey DRG neurons and confirm the absence of functional P2X2/3 receptors. Interestingly, native P2X3 receptors in rat and monkey DRGs show similar agonist potency, but different antagonist potencies for TNP-ATP [2-O-(2,4,6-trinitrophenyl)-ATP] and RO51. This unexpected difference in antagonist potency was confirmed by comparing rat and human P2X3 receptors in HEK293 cells. Mutagenesis studies reveal that two extracellular residues, A197 and T202, are synergistically responsible for the potency drop in primate P2X3 receptors. These results uncover species-specific P2X3 pharmacology and identify key mechanisms impacting the translatability of potential analgesics targeting P2X3 receptors.
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Temperature-responsive smart nanoreactors: poly(N-isopropylacrylamide)-coated Au@mesoporous-SiO2 hollow nanospheres.
Langmuir
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A nanoreactor with temperature-responsive poly(N-isopopylacrylamide) (PNIPAM) coated on the external pore mouth of mesoporous silica hollow spheres and Au nanoparticles at the internal pore mouth were fabricated. Such spatial separation allows both Au nanoparticles and PNIPAM to function without interfering with each other. Transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectra, and temperature-dependent optical transmittance curves demonstrate successful grafting of PNIPAM. This nanoreactor shows repeated on/off catalytic activity switched by temperature control. It shows excellent catalytic activity toward 4-nitrophenol (4-NP) reduction at 30 °C [below lower critical solution temperature (LCST) of PNIPAM] with a turnover frequency (TOF) of 14.8 h(-1). However, when the temperature was 50 °C (above LCST), the TOF dropped to 2.4 h(-1). Kinetic studies indicated that diffusion into the mesopores of the catalyst was the key factor, and the temperature-responsive behavior of PNIPAM was able to control this diffusion.
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[Study on anti-proliferation activity and the mechanisms of alkaloid monomers from Gelsemium elegans on HepG2 cell in vitro].
Zhong Yao Cai
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To investigate the effects of alkaloid monomers from Gelsemium elegans on proliferation of HepG2 cell in vitro and the possible mechanism.
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Superb adsorption capacity and mechanism of flowerlike magnesium oxide nanostructures for lead and cadmium ions.
ACS Appl Mater Interfaces
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A facile method based on microwave-assisted solvothermal process has been developed to synthesize flowerlike MgO precursors, which were then transformed to MgO by simple calcinations. All the chemicals used (magnesium nitrate, urea, and ethanol) were low cost and environmentally benign. The products were characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution TEM, and N(2) adsorption-desorption methods. These flowerlike MgO nanostructures had high surface area and showed superb adsorption properties for Pb(II) and Cd(II), with maximum capacities of 1980 mg/g and 1500 mg/g, respectively. All these values are significantly higher than those reported on other nanomaterials. A new adsorption mechanism involving solid-liquid interfacial cation exchange between magnesium and lead or cadmium cations was proposed and confirmed.
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What is Visualize?

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

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

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.