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Find video protocols related to scientific articles indexed in Pubmed.
Fabricating Surfaces with Tunable Wettability and Adhesion by Ionic Liquids in a Wide Range.
Small
PUBLISHED: 10-13-2014
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A series of surfaces that can either be fully wetted or non-wetted by three kinds of ionic liquids (ILs) are successfully designed by rationally controlling surface chemistries and structures. Meanwhile, the adhesion forces between these surfaces and the ILs can also be effectively modulated in a wide range. This fundamental research will greatly promote the development of IL-based materials in practical applications.
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[Analysis and prenatal diagnosis of deafness-related gene mutations in patients with nonsyndromic hearing loss].
Zhonghua Yi Xue Yi Chuan Xue Za Zhi
PUBLISHED: 10-10-2014
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To analyze deaf-related genes in patients with nonsyndromic hearing loss (NSHL) and set up a prenatal diagnosis system for such patients.
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Tunable magnetic and electronic properties of BN nanosheets with triangular defects: a first-principles study.
J Phys Condens Matter
PUBLISHED: 10-09-2014
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Experimentally, vacancy defects are commonly observed in BN nanosheets, expecially nitrogen-terminated triangular defects. Based on first-principles calculations, we systematically investigate the magnetic and electronic properties of BN nanosheets with these triangular vacancies (referred to as Vi(i = 1 - 4) defects with i representing the number of N atoms on each side of the triangle). It is found that the Vi defects bring diverse magnetic states into BN sheets, which are ferrimagnetic for V1, nonmagnetic for V2, ferrimagnetic for V3 and antiferromagnetic for V4 defects. When the isotropic strains are applied, the ferrimagnetic state is sustained for V1 defect, whereas the V2 defect undergoes a nonmagnetic to antiferromagnetic transition and the V3, V4 defects experience an abrupt change in the absolute magnetic moments under small strains, which are originated from the N-N bond breaking at these defects. Different from the BN nanoribbons, the antiparallel coupling is more favorable for the N atoms at the edges of triangular defects. Due to the triangular defects, the band gaps of BN sheets are reduced substantially, which could be further modulated by the strains. When the defective BN sheets serve as a substrate for graphene, the V1, V3 and V4 defects in BN would induce p-type doping in the graphene sheet. Interestingly, when the V2 defect is embedded in BN sheets, the doping behavior of graphene can be well-controlled by the strain, which is charge neutral at the strain-free state and p-type doped under strains. Our studies demonstrate that the rich magnetic and electronic properties of BN sheets with triangular defects enable the system's potential applications in nanodevices.
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Glipizide, an antidiabetic drug, suppresses tumor growth and metastasis by inhibiting angiogenesis.
Oncotarget
PUBLISHED: 10-09-2014
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Angiogenesis is involved in the development, progression and metastasis of various human cancers. Herein, we report the discovery of glipizide, a widely used drug for type 2 diabetes mellitus, as a promising anticancer agent through the inhibition of tumor angiogenesis. By high-throughput screening (HTS) of an FDA approved drug library utilizing our in vivo chick embryo chorioallantoic membrane (CAM) and yolk sac membrane (YSM) models, glipizide has been identified to significantly inhibit blood vessel formation and development. Moreover, glipizide was found to suppress tumor angiogenesis, tumor growth and metastasis using xenograft tumor and MMTV-PyMT transgenic mouse models. We further revealed that the anticancer capability of glipizide is not attributed to its antiproliferative effects, which are not significant against various human cancer cell lines. To investigate whether its anticancer efficacy is associated with the glucose level alteration induced by glipizide application, glimepiride, another medium to long-acting sulfonylurea antidiabetic drug in the same class, was employed for the comparison studies in the same fashion. Interestingly, glimepiride has demonstrated no significant impact on the tumor growth and metastasis, indicating that the anticancer effects of glipizide is not ascribed to its antidiabetic properties. Furthermore, glipizide suppresses endothelial cell migration and the formation of tubular structures, thereby inhibiting angiogenesis by up-regulating the expression of natriuretic peptide receptor A. These findings uncover a novel mechanism of glipizide as a potential cancer therapy, and also for the first time, provide direct evidence to support that treatment with glipizide may reduce the cancer risk for diabetic patients.
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Intense exercise can cause excessive apoptosis and synapse plasticity damage in rat hippocampus through Ca²? overload and endoplasmic reticulum stress-induced apoptosis pathway.
Chin. Med. J.
PUBLISHED: 10-01-2014
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Intense exercise can cause injury and apoptosis, but few studies have reported its effect on the central nervous system (CNS). The initial reason for hippocampus injury is the excitotoxicity of glutamate and calcium overload. Intracellular free Ca(2+) ([Ca(2+)]i) overload may trigger the apoptosis pathway and neuron damage. The aim of this study was to investigate whether intense exercise could cause hippocampus apoptosis and neuron damage and then to determine which pathway was activated by this apoptosis.
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Green synthesis of large-scale highly ordered core@shell nanoporous Au@Ag nanorod arrays as sensitive and reproducible 3D SERS substrates.
ACS Appl Mater Interfaces
PUBLISHED: 09-10-2014
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We present a simple green synthetic approach to large-scale and highly ordered arrays of vertical nanoporous Au nanorods, with an ultrathin Ag-layer in situ electrodeposited on each nanoporous Au nanorod (denoted as core@shell nanoporous Au@Ag nanorod). As both the nanopores within each nanorod and the gaps between the neighboring nanorods create three-dimensional (3D) "hot spots" homogeneously distributed throughout the whole substrate, the core@shell nanoporous Au@Ag nanorod arrays were proved to be sensitive and reproducible surface-enhanced Raman scattering (SERS) substrates. Not only universal probe molecules (rhodamine 6G, R6G) but also nonadsorbing molecules (polychlorinated biphenyls, PCBs) have been detected by using the substrates. After mono-6-thio-?-cyclodextrin (HS-?-CD) was modified to efficiently capture more PCBs molecules, the detection limit of PCBs was further reduced to 5.35 × 10(-7) M. As a trial of practical application, R6G and PCBs with different molar ratios in their mixed solutions were identified, and two congeners of PCBs in their mixture could also be distinguished, showing great potentials in real-time simultaneous detection of multiple pollutants.
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A comparative study of calcium sulfate artificial bone graft versus allograft in the reconstruction of bone defect after tumor curettage.
Chin. Med. J.
PUBLISHED: 09-06-2014
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Cavity reconstruction after benign bone tumor removal is varied and controversial. Allograft is widely used but is associated with complications. New bone substitutes, such as calcium sulfate artificial bone, have been introduced for bone tumor operation. However, the bone healing response of artificial bone has not been compared with allograft bone. We therefore compared calcium sulfate grafts (study group) with bone allografts (control group) for the treatment of benign bone tumors.
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A phase I study of the histone deacetylase (HDAC) inhibitor entinostat, in combination with sorafenib in patients with advanced solid tumors.
Invest New Drugs
PUBLISHED: 08-27-2014
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Based on preclinical data demonstrating cytotoxic synergy between sorafenib and entinostat, a phase I study of this combination was conducted in patients with advanced solid tumors. Enrollment followed the traditional "3?+?3" dose escalation scheme. Entinostat was given orally once every 2 weeks, starting at a dose of 4 mg and escalating to 6 and 10 mg every 2 weeks. Sorafenib was administered as a continuous oral dose, escalating from 200 to 400 mg twice daily. A treatment cycle was 28 days. A total of 31 patients with advanced solid tumors were enrolled on the study. The three dose-limiting toxicities (DLTs) observed were grade 3 hand-foot syndrome, nausea/vomiting, and fatigue. MTD was not reached. The recommended phase II dose was defined as the full dose of the respective drugs administered individually. The most common grade 3-4 toxicities were muscle weakness (13 %), skin rash (10 %), fatigue (6 %), diarrhea (6 %), and hand-foot syndrome (3 %). One NSCLC patient achieved a partial response. Two patients (adenocarcinoma of GE junction and Hurthle cell carcinoma of the thyroid) were on the study for more than 9 months with stable disease. The combination of entinostat and sorafenib was well tolerated. Entinostat 10 mg orally once every 2 weeks in combination with sorafenib 400 mg orally twice daily, representing full single agent doses of each drug was identified as the recommended phase 2 dose (RP2D). These data support future clinical development of the combination of entinostat and sorafenib.
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Gold nanorod-templated synthesis of polymetallic hollow nanostructures with enhanced electrocatalytic performance.
Nanoscale
PUBLISHED: 08-26-2014
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Anisotropic polymetallic hollow nanostructures are highly desired for many applications because of their unique morphology, large specific surface areas and attractive electronic effects. Here, a simple method using gold nanorods as a self-sacrificed template has been developed for the fabrication of hollow dumbbell-like nanorods of Au@PtAg. The formation of the hollow structures involves the growth of another metallic shell first, and then the etching of gold nanorods, which is induced by oxygen and ascorbic acid. The lattice mismatch and cohesive energy of the shell, along with its surface passivation, greatly affect the subsequent etching and the resulting products, as has been demonstrated by a positive control in the case of Rh and a negative control in the case of Pd. Hollow dumbbell-like nanorods of Au@PtAg show great enhancement for the dehydrogenation pathway in the oxidation of formic acid, as compared to solid Au@PtAg nanorods, PtAu nanotubes and commercial Pt/C.
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Neuroprotection by Acetyl-11-Keto-?-Boswellic Acid, in Ischemic Brain Injury Involves the Nrf2/HO-1 defense Pathway.
Sci Rep
PUBLISHED: 08-13-2014
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Stroke is a complex disease involved oxidative stress-related pathways in its pathogenesis. The nuclear factor erythroid-2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway has been considered a potential target for neuroprotection in stroke. Acetyl-11-Keto-?-Boswellic Acid (AKBA) is an active triterpenoid compound from the extract of Boswellia serrate. The present study was to determine whether AKBA, a novel Nrf2 activator, can protect against cerebral ischemic injury. The stroke model was produced in Sprague-Dawley rats via middle cerebral artery occlusion. To model ischemia-like conditions in vitro, primary cultured cortical neurons were exposed to transient oxygen and glucose deprivation (OGD). Treatment of AKBA significantly reduced infarct volumes and apoptotic cells, and also increased neurologic scores by elevating the Nrf2 and HO-1 expression in brain tissues in middle cerebral artery occlusion (MCAO) rats at 48?hours post reperfusion. In primary cultured neurons, AKBA increased the Nrf2 and HO-1 expression, which provided protection against OGD-induced oxidative insult. Additionally, AKBA treatment increased Nrf2 binding activity to antioxidant-response elements (ARE). The protective effect of AKBA was attenuated by knockdown of Nrf2 or HO-1. In conclusion, these findings provide evidence that AKBA protects neurons against ischemic injury, and this neuroprotective effect involves the Nrf2/HO-1 pathway.
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Determination of multiple pesticides in fruits and vegetables using a modified quick, easy, cheap, effective, rugged and safe method with magnetic nanoparticles and gas chromatography tandem mass spectrometry.
J Chromatogr A
PUBLISHED: 08-13-2014
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Based on a modified quick, easy, cheap, effective, rugged and safe (QuEChERS) sample preparation method with Fe3O4 magnetic nanoparticles (MNPs) as the adsorbing material and gas chromatography-tandem mass spectrometry (GC-MS/MS) determination in multiple reaction monitoring (MRM) mode, we established a new method for the determination of multiple pesticides in vegetables and fruits. It was determined that bare MNPs have excellent function as adsorbent when purified, and it is better to be separated from the extract. The amount of MNPs influenced the clean-up performance and recoveries. To achieve the optimum performance of modified QuEChERS towards the target analytes, several parameters including the amount of the adsorbents and purification time were investigated. Under the optimum conditions, recoveries were evaluated in four representative matrices (tomato, cucumber, orange and apple) with the spiked concentrations of 10 ?g kg(-1), 50 ?g kg(-1)and 200 ?g kg(-1) in all cases. The results showed that the recovery of 101 pesticides ranged between 71.5 and 111.7%, and the relative standard deviation was less than 10.5%. The optimum clean-up system improved the purification efficiency and simultaneously obtained satisfactory recoveries of multiple pesticides, including planar-ring pesticides. In short, the modified QuEChERS method in addition to MNPs used for removing impurities improved the speed of sample pre-treatment and exhibited an enhanced performance and purifying effect.
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Differential modulation of auditory responses to attended and unattended speech in different listening conditions.
Hear. Res.
PUBLISHED: 08-11-2014
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This study investigates how top-down attention modulates neural tracking of the speech envelope in different listening conditions. In the quiet conditions, a single speech stream was presented and the subjects paid attention to the speech stream (active listening) or watched a silent movie instead (passive listening). In the competing speaker (CS) conditions, two speakers of opposite genders were presented diotically. Ongoing electroencephalographic (EEG) responses were measured in each condition and cross-correlated with the speech envelope of each speaker at different time lags. In quiet, active and passive listening resulted in similar neural responses to the speech envelope. In the CS conditions, however, the shape of the cross-correlation function was remarkably different between the attended and unattended speech. The cross-correlation with the attended speech showed stronger N1 and P2 responses but a weaker P1 response compared to the cross-correlation with the unattended speech. Furthermore, the N1 response to the attended speech in the CS condition was enhanced and delayed compared with the active listening condition in quiet, while the P2 response to the unattended speaker in the CS condition was attenuated compared with the passive listening in quiet. Taken together, these results demonstrate that top-down attention differentially modulates envelope-tracking neural activity at different time lags and suggest that top-down attention can both enhance the neural responses to the attended sound stream and suppress the responses to the unattended sound stream.
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Both gene deletion and promoter hyper-methylation contribute to the down-regulation of ZAC/PLAGL1 gene in gastric adenocarcinomas: A case control study.
Clin Res Hepatol Gastroenterol
PUBLISHED: 08-06-2014
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Pleiomorphic adenoma gene-like 1 (PLAGL1, also known as LOT1 and ZAC) is a zinc-finger nuclear transcription factor, which possesses antiproliferative effects and is frequently epigenetically silenced during tumorigenesis. PLAGL1 gene is located on 6q24-25, a chromosomal region that is frequently deleted in various kinds of cancers. Both promoter hyper-methylation and loss of heterozygosity may lead to the down-regulation of PLAGL1 in human somatic cancers. Here we aimed to investigate the abnormalities of PLAGL1 in gastric cancers.
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Chromatographic Fingerprint Analysis of the Floral Parts of Trollius chinensis.
J Chromatogr Sci
PUBLISHED: 07-28-2014
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This study provided a practical procedure, for the first time, to compare the component difference of the floral parts of Trollius chinensis and identify the characteristic peaks of each floral part using the high-performance liquid chromatographic fingerprint technique followed by similarity analysis. The results showed that the constituents of different floral parts exhibited lower similarity than those of the same part. It can be concluded that the procedure established herein is useful for analysis of variability in constituent distribution of herbal drugs, and the components are unevenly distributed in the floral parts of T. chinensis.
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Effect of niacin on lipids and glucose in patients with type 2 diabetes: A meta-analysis of randomized, controlled clinical trials.
Clin Nutr
PUBLISHED: 07-04-2014
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This study aims to conduct a meta-analysis to evaluate the effects of niacin on serum lipids and glucose in patients with type 2 diabetes mellitus (T2DM).
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[Effects of operating parameters on organic toxicity of sludge treating synthetic bisphenol A wastewater].
Huan Jing Ke Xue
PUBLISHED: 06-21-2014
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In order to investigate the influence of hydraulic retention time (HRT) and sludge retention time (SRT) on sludge organic toxicity in sequencing batch reactors (SBR(S)), the sludge toxicity was compared when HRT and SRT were controlled at various levels. The influents COD were controlled at around 300 mg x L(-1), HRT and SRT were changed from 12 h to 8 h and from 20 d to 10 d, respectively. The effluents COD, BPA contents both in liquid and sludge were measured, and sludge toxicity was also analyzed and compared between the blank group (no BPA content) and BPA control groups (40 mg x L(-1)). The results showed that the effluents COD of two SBRs were both below 50 mg x L(-1), and there were no BPA content in liquid and sludge. Furthermore, decrease HRT and SRT is helpful to remove BPA and reduce sludge toxicity. Additional investigation revealed a correlation between the properties of bacterial community and total sludge toxicity by the PCR-DGGE analysis, and different influent compositions and operation parameters were the main reasons for leading the difference of sludge toxicity.
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An enteric virus can replace the beneficial function of commensal bacteria.
Nature
PUBLISHED: 06-05-2014
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Intestinal microbial communities have profound effects on host physiology. Whereas the symbiotic contribution of commensal bacteria is well established, the role of eukaryotic viruses that are present in the gastrointestinal tract under homeostatic conditions is undefined. Here we demonstrate that a common enteric RNA virus can replace the beneficial function of commensal bacteria in the intestine. Murine norovirus (MNV) infection of germ-free or antibiotic-treated mice restored intestinal morphology and lymphocyte function without inducing overt inflammation and disease. The presence of MNV also suppressed an expansion of group 2 innate lymphoid cells observed in the absence of bacteria, and induced transcriptional changes in the intestine associated with immune development and type I interferon (IFN) signalling. Consistent with this observation, the IFN-? receptor was essential for the ability of MNV to compensate for bacterial depletion. Importantly, MNV infection offset the deleterious effect of treatment with antibiotics in models of intestinal injury and pathogenic bacterial infection. These data indicate that eukaryotic viruses have the capacity to support intestinal homeostasis and shape mucosal immunity, similarly to commensal bacteria.
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Simultaneous adsorption and reduction of U(VI) on reduced graphene oxide-supported nanoscale zerovalent iron.
J. Hazard. Mater.
PUBLISHED: 05-30-2014
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The reduced graphene oxide-supported nanoscale zero-valent iron (nZVI/rGO) composites were synthesized by chemical deposition method and were characterized by SEM, high resolution TEM, Raman and potentiometric acid-base titrations. The characteristic results showed that the nZVI nanoparticles can be uniformly dispersed on the surface of rGO. The removal of U(VI) on nZVI/rGO composites as a function of contact time, pH and U(VI) initial concentration was investigated by batch technique. The removal kinetics of U(VI) on nZVI and nZVI/rGO were well simulated by a pseudo-first-order kinetic model and pseudo-second-order kinetic model, respectively. The presence of rGO on nZVI nanoparticles increased the reaction rate and removal capacity of U(VI) significantly, which was attributed to the chemisorbed OH(-) groups of rGO and the massive enrichment of Fe(2+) on rGO surface by XPS analysis. The XRD analysis revealed that the presence of rGO retarded the transformation of iron corrosion products from magnetite/maghemite to lepidocrocite. According to the fitting of EXAFS spectra, the UC (at ?2.9?) and UFe (at ?3.2?) shells were observed, indicating the formation of inner-sphere surface complexes on nZVI/rGO composites. Therefore, the nZVI/rGO composites can be suitable as efficient materials for the in-situ remediation of uranium-contaminated groundwater in the environmental pollution management.
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Fluorescence enhancement of cadmium selenide quantum dots assembled on silver nanoparticles and its application to glucose detection.
Langmuir
PUBLISHED: 05-30-2014
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In this work, a new assembled glucose sensor based on the Ag nanoparticle (AgNP)-enhanced fluorescence of CdSe quantum dots (QDs) was developed. The mercaptoglycerol-modified AgNPs and aminophenylboronic acid-functionalized CdSe QDs are assembled into AgNP-CdSe QD complexes through the formation of a boronate ester bond. As compared to that of bare CdSe QDs, up to a 9-fold fluorescence enhancement and a clear blue shift of the emission peak for AgNP-CdSe QD complexes were observed, which is attributed to the surface plasmon resonance of AgNPs. In addition, the as-formed complexes are gradually disassembled in the presence of glucose molecules because they can replace the AgNPs by competitive binding with boronic acid groups, resulting in the weakening of fluorescence enhancement. The decrease in fluorescence intensity presents a linear relationship with glucose concentration in the range from 2 to 52 mM with a detection limit of 1.86 mM. Such a metal-enhanced QDs fluorescence system may have promising applications in chemical and biological sensors.
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Controlled doping of silicon nanocrystals investigated by solution-processed field effect transistors.
ACS Nano
PUBLISHED: 05-27-2014
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The doping of semiconductor nanocrystals (NCs), which is vital for the optimization of NC-based devices, remains a significant challenge. While gas-phase plasma approaches have been successful in incorporating dopant atoms into NCs, little is known about their electronic activation. Here, we investigate the electronic properties of doped silicon NC thin films cast from solution by field effect transistor analysis. We find that, analogous to bulk silicon, boron and phosphorus electronically dope Si NC thin films; however, the dopant activation efficiency is only ?10(-2)-10(-4). We also show that surface doping of Si NCs is an effective way to alter the carrier concentrations in Si NC films.
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Effect of spray aeration on organics and nitrogen removal in vertical subsurface flow constructed wetland.
Chemosphere
PUBLISHED: 05-07-2014
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The objective of present study was to assess the simultaneous removal of organics and nitrogen by four lab-scale vertical subsurface flow constructed wetlands (V-SFCWs). The emergent plants employed were Canna indica. Five-month experiments showed that the planted and aerated system largely reduced the COD by 95%, NH4 by 88% and total inorganic nitrogen (TIN) by 83%. It outperformed the unplanted or simple aerated system and was much better than non-aerated system. The study provided a strong evidence to support widespread research and application of spray aeration as a low-cost and energy-efficient aeration technology in V-SFCWs.
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Tenosynovial giant cell tumors lacking giant cells: report of diagnostic pitfalls.
Ann. Clin. Lab. Sci.
PUBLISHED: 05-06-2014
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Tenosynovial giant cell tumors are a group of neoplastic disorders that involve synovium-lined tendon sheaths, synovial joints, and adjacent soft tissue. They are divided into localized and diffuse subtypes. TSGCTs have well-established clinical and histological diagnostic criteria; however, the subtypes and nomenclature can be confusing. They also pose diagnostic challenges when they occur in atypical locations or without multinucleated giant cells. With the possibility for systemic targeted therapy in relapsing pigmented villonodular tenosynovitis and diffuse-type giant cell tumor, accurate diagnosis and subtyping of TSGCTs is increasingly important. We report two cases of TSGCTs in order to elucidate the diagnostic nomenclature, clinicopathological features, differential diagnosis, and diagnostic pitfalls. Recent advancements in the pathogenesis and targeted therapy of TSGCTs are also discussed.
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Polymerizable disulfide paclitaxel prodrug for controlled drug delivery.
Mater Sci Eng C Mater Biol Appl
PUBLISHED: 04-26-2014
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A polymerizable disulfide paclitaxel (PTX) prodrug was synthesized by the consequential esterification reactions of 3,3'-dithiodipropionic acid (DTPA), a disulfide compound containing two active carboxyl groups, with 2-hydroxyethyl methacrylate (HEMA) and PTX. The structure of the prodrug was confirmed by (1)H NMR characterization. Then, the polymerizable prodrug was copolymerized with poly(ethylene glycol) methyl ether methacrylate (PEGMEA) to obtain a copolymer with hydrophilic PEG side chains and PTX covalently linked onto the backbone via disulfide bonds. The loading content of PTX was 23%. In aqueous solution, this copolymer prodrug could self-assemble into micelles, with hydrophobic PTX as the cores and hydrophilic PEG-segment as the shells. In vitro cell assay demonstrated that this copolymer prodrug showed more apparent cytotoxicity to cancer cells than to human normal cells. After incubation for 48h, the cell viability of HEK-293 cells (human embryo kidney cells) at 0.1?g/mL PTX still remained more than 90%, however, that of HeLa cells (human cervical cancer cells) decreased to 52%.
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Occurrence, sources, and ecological risks of PBDEs, PCBs, OCPs, and PAHs in surface sediments of the Yangtze River Delta city cluster, China.
Environ Monit Assess
PUBLISHED: 04-17-2014
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Polybrominated diphenyl ethers (PBDEs), organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) in 25 surface sediments in three cities (Nantong, Wuxi, and Suzhou) in the Yangtze River Delta, eastern China were measured. The mean concentrations were 378, 45.8, 1.98, 4,002 ng/g for PBDEs, OCPs, PCBs, and PAHs, respectively. Their levels in the sediments in the three cities were generally consistent with the city industrialization. PBDEs and OCPs were markedly dominated by deca-BDE (>90 %) and DDTs (>70 %). A principle component analysis of the analytes identified three major factors suggesting different sources of the contaminants in the sediments. PBDEs and the organic carbon in the sediments have common sources from industrial activities; whereas OCPs and PCBs, correlated with the second factor, were mainly from historical sources. The third factor with loadings of PAHs is indicative of various combustion sources. Ecological risk assessment indicated that the potential highest risk is from DDTs, for which 22 sites exceed the effects range low (ERL) values and three sites exceed the effects range median (ERM) value.
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Characterization of organic membrane foulants in a forward osmosis membrane bioreactor treating anaerobic membrane bioreactor effluent.
Bioresour. Technol.
PUBLISHED: 04-11-2014
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In this study, two aerobic forward osmosis (FO) membrane bioreactors (MBR) were utilized to treat the effluent of mesophilic (35°C) and atmospheric (25°C) anaerobic MBRs, respectively. The results showed that the FO membrane process could significantly improve the removal efficiencies of N and P. Meanwhile, the flux decline of the FOMBR treating effluent of mesophilic AnMBR (M-FOMBR) was higher than that treating effluent of atmospheric AnMBR (P-FOMBR). The organic membrane foulants in the two FOMBRs were analyzed to understand the membrane fouling behavior in FO processes. It was found that the slightly increased accumulation of protein-like substances into external foulants did not cause faster flux decline in P-FOMBR than that in M-FOMBR. However, the quantity of organic matter tended to deposit or adsorb into FO membrane pores in P-FOMBR was less than that in M-FOMBR, which was accordance with the tendency of membrane fouling indicated by flux decline.
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Molecular evolution and functional characterisation of an ancient phenylalanine ammonia-lyase gene (NnPAL1) from Nelumbo nucifera: novel insight into the evolution of the PAL family in angiosperms.
BMC Evol. Biol.
PUBLISHED: 03-24-2014
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Phenylalanine ammonia-lyase (PAL; E.C.4.3.1.5) is a key enzyme of the phenylpropanoid pathway in plant development, and it catalyses the deamination of phenylalanine to trans-cinnamic acid, leading to the production of secondary metabolites. This enzyme has been identified in many organisms, ranging from prokaryotes to higher plants. Because Nelumbo nucifera is a basal dicot rich in many secondary metabolites, it is a suitable candidate for research on the phenylpropanoid pathway.
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Dietary ellagic acid improves oxidant-induced endothelial dysfunction and atherosclerosis: role of Nrf2 activation.
Int. J. Cardiol.
PUBLISHED: 03-17-2014
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Oxidative stress-induced vascular endothelial cell injury is a major factor in the pathogenesis of atherosclerosis. Several evidences indicate that ellagic acid (EA), a phenolic compound, contributes to cardiovascular health. This study was to investigate the effects of EA on endothelial dysfunction and atherosclerosis via antioxidant-related mechanisms.
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A precise chloroplast genome of Nelumbo nucifera (Nelumbonaceae) evaluated with Sanger, Illumina MiSeq, and PacBio RS II sequencing platforms: insight into the plastid evolution of basal eudicots.
BMC Plant Biol.
PUBLISHED: 03-11-2014
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BackgroundThe chloroplast genome is important for plant development and plant evolution. Nelumbo nucifera is one member of relict plants surviving from the late Cretaceous. Recently, a new sequencing platform PacBio RS II, known as `SMRT (Single Molecule, Real-Time) sequencing¿, has been developed. Using the SMRT sequencing to investigate the chloroplast genome of N. nucifera will help to elucidate the plastid evolution of basal eudicots.ResultsThe sizes of the de novo assembled complete chloroplast genome of N. nucifera were 163,307 bp, 163,747 bp and 163,600 bp with average depths of coverage of 7×, 712× and 105× sequenced by Sanger, Illumina MiSeq and PacBio RS II, respectively. The precise chloroplast genome of N. nucifera was obtained from PacBio RS II data proofread by Illumina MiSeq reads, with a quadripartite structure containing a large single copy region (91,846 bp) and a small single copy region (19,626 bp) separated by two inverted repeat regions (26,064 bp). The genome contains 113 different genes, including four distinct rRNAs, 30 distinct tRNAs and 79 distinct peptide-coding genes. A phylogenetic analysis of 133 taxa from 56 orders indicated that Nelumbo with an age of 177 million years is a sister clade to Platanus, which belongs to the basal eudicots. Basal eudicots began to emerge during the early Jurassic with estimated divergence times at 197 million years using MCMCTree. IR expansions/contractions within the basal eudicots seem to have occurred independently.ConclusionsBecause of long reads and lack of bias in coverage of AT-rich regions, PacBio RS II showed a great promise for highly accurate `finished¿ genomes, especially for a de novo assembly of genomes. N. nucifera is one member of basal eudicots, however, evolutionary analyses of IR structural variations of N. nucifera and other basal eudicots suggested that IR expansions/contractions occurred independently in these basal eudicots or were caused by independent insertions and deletions. The precise chloroplast genome of N. nucifera will present new information for structural variation of chloroplast genomes and provide new insight into the evolution of basal eudicots at the primary sequence and structural level.
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Biosorption of uranium on Bacillus sp. dwc-2: preliminary investigation on mechanism.
J Environ Radioact
PUBLISHED: 03-04-2014
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In this paper, the biosorption mechanisms of uranium on an aerobic Bacillus sp. dwc-2, isolated from a potential disposal site for (ultra-) low uraniferous radioactive waste in Southwest China, was explored by transmission electron microscopy (TEM), energy dispersive X-ray (EDX) analysis, FT-IR spectroscopy, proton induced X-ray emission (PIXE) and enhanced proton backscattering spectrometry (EPBS). The biosorption experiments for uranium were carried out at a low pH (pH 3.0), where the uranium solution speciation is dominated by highly mobile uranyl ions. The bioaccumulation was found to be the potential mechanism involved in uranium biosorption by Bacillus sp. dwc-2, and the bioaccumulated uranium was deposited in the cell interior as needle shaped particles at pH 3.0, as revealed by TEM analysis as well as EDX spectra. FTIR analysis further suggested that the absorbed uranium was bound to amino, phosphate and carboxyl groups of bacterial cells. Additionally, PIXE and EPBS results confirmed that ion-exchange also contributed to the adsorption process of uranium. All the results implied that the biosorption mechanism of uranium on Bacillus sp. is complicated and at least involves bioaccumulation, ion exchange and complexation process.
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The efficacy and safety of thalidomide-based therapy in patients with advanced non-small cell lung cancer: a meta-analysis.
Contemp Oncol (Pozn)
PUBLISHED: 02-28-2014
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Several randomized controlled clinical trials have compared therapy with or without thalidomide in the treatment of advanced non-small cell lung cancer (NSCLC). However, these studies did not produce consistent results. We carried out a meta-analysis to determine the efficacy and safety of thalidomide-based therapy in patients with advanced NSCLC. For this meta-analysis, we selected randomized clinical trials that compared thalidomide in combination with other therapy or other therapy alone in patients with advanced NSCLC. The outcomes included median overall survival (OS), one- and two-year survival, tumor response, and toxicities. Hazard ratios (HRs) or risk ratios (RRs) were reported with 95% confidence intervals (CIs). A total of 5 eligible trials were included for the meta-analysis, with 729 patients in the thalidomide group and 711 patients in the control group. Compared with non-thalidomide-based therapy, patients receiving thalidomide plus other therapy did not differ significantly in terms of one- and two-year survival or tumor response (RR = 1.32, 95% CI: 0.66-2.63, p = 0.43; RR = 1.22, 95% CI: 0.48-3.11, p = 0.68; RR = 1.05, 95% CI: 0.92-1.19, p = 0.51, respectively). However, thalidomide-based therapy induced more grade 3-4 dizziness and constipation (RR = 2.05, 95% CI: 1.10-3.81, p = 0.02; RR = 4.78, 95% CI: 1.84-12.38, p = 0.001, respectively). The addition of thalidomide to other therapy did not improve survival and tumor response in patients with advanced NSCLC, and thalidomide-based therapy was associated with more grade 3/4 dizziness and constipation.
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Roles of the co-culture of human umbilical cord Wharton's jelly-derived mesenchymal stem cells with rat pancreatic cells in the treatment of rats with diabetes mellitus.
Exp Ther Med
PUBLISHED: 02-26-2014
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The aim of the present study was to investigate the roles of the co-culture of human umbilical cord Wharton's jelly-derived mesenchymal stem cells (hUC-MSCs) with rat pancreatic cells in the treatment of rats with diabetes mellitus. hUC-MSCs were isolated and passaged, followed by Transwell co-culture with rat pancreatic cells. The induced islet-like cell clusters were transplanted into the renal capsule in rats with streptozotocin (STZ)-induced diabetes mellitus. The effects of co-culture on blood glucose levels in rats were observed. The isolated hUC-MSCs expressed the specific surface markers, including cluster of differentiation 44 (CD44) (91.4%), CD29 (91.3%) and CD105 (99.2%). Following co-culture with hUC-MSCs for 7 and 10 days, the rat pancreatic cells were strongly stained by pancreatic and duodenal homeobox-1 and human insulin. The insulin and C-peptide concentrations were increased significantly compared to the pure culture group. One week following the transplantation of induced islet-like cells into the renal capsule, the blood glucose level of rats in the STZ experimental group was significantly lower than that of the STZ control group. There were notable 5-bromo-2'-deoxyuridine-positive nuclei and insulin-positive cytoplasm in the renal capsule following cell transplantation. Therefore, co-culture of hUC-MSCs with rat pancreatic cells can lower the blood glucose levels in rats with diabetes mellitus.
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Comparative expression profiling of miRNAs between the cytoplasmic male sterile line MeixiangA and its maintainer line MeixiangB during rice anther development.
Planta
PUBLISHED: 02-26-2014
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miRNAs are involved in the pollen development during the CMS occurrence in rice. miRNAs are 20-24 nt endogenously expressed small RNAs that play key roles in the regulation of many growth and developmental processes in plants. The knowledge on cytoplasmic male sterility (CMS) regulation by miRNAs in rice is rather limited. In this study, Illumina sequencing was employed to examine the expression profiles of rice anther miRNAs from the CMS line MeixiangA (MxA) and its maintainer line MeixiangB (MxB). A total of 518 known miRNAs and 144 novel miRNAs were identified during rice anther development. Based on the number of sequencing reads, a total of 24 miRNAs were discovered to be differentially expressed between MxA and MxB, and the results were partially validated by qRT-PCR. Among these, 16 miRNAs were decreased and 8 miRNAs were increased in MxA compared with MxB. Target prediction showed that they target genes encoding EF-hand family proteins, F-box domain-containing proteins, MYB transcription factors, PPR-containing proteins and transposons. The expression patterns for targets of osa-miR528, osa-miR5793, osa-miR1432, osa-miR159, osa-miR812d, osa-miR2118c, osa-miR172d and osa-miR5498 were selectively examined, and the results showed that there was a negative correlation on the expression patterns between miRNAs and their targets. These targets have previously been reported to be related with pollen development and male sterility, suggesting that miRNAs might act as regulators of CMS occurrence in rice anthers. Furthermore, miRNA editing events were observed. The U ? C and U ? A editing phenomenon was validated by molecular cloning and sequencing. These findings contribute to our understanding of the roles of miRNAs during anther development and CMS occurrence in rice.
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Structure of the Na,K-ATPase regulatory protein FXYD2b in micelles: Implications for membrane-water interfacial arginines.
Biochim. Biophys. Acta
PUBLISHED: 02-26-2014
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FXYD2 is a membrane protein responsible for regulating the function of the Na,K-ATPase in mammalian kidney epithelial cells. Here we report the structure of FXYD2b, one of two splice variants of the protein, determined by NMR spectroscopy in detergent micelles. Solid-state NMR characterization of the protein embedded in phospholipid bilayers indicates that several arginine side chains may be involved in hydrogen bond interactions with the phospholipid polar head groups. The structure and the NMR data suggest that FXYD2b could regulate the Na,K-ATPase by modulating the effective membrane surface electrostatics near the ion binding sites of the pump. This article is part of a Special Issue entitled: NMR Spectroscopy for Atomistic Views of Biomembranes and Cell Surfaces.
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Overexpression of Tiam1 is associated with malignant phenotypes of nasopharyngeal carcinoma.
Oncol. Rep.
PUBLISHED: 02-21-2014
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The aim of the present study was to analyze the roles of T lymphoma invasion and metastasis 1 (Tiam1) in nasopharyngeal carcinoma (NPC) progression and its correlation with clinicopathological features, including the survival of patients with NPC. Tiam1 protein expression in NPC tissues was examined using immunohistochemistry. Reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescence staining were performed to detect the expression of Tiam1 in 6 NPC cell lines. Stable Tiam1-overexpressing NPC cells using a transfection technique and Tiam1-silencing NPC cells using short hairpin RNA were constructed. Subsequently, MTT assay, plate and soft agar colony formation assays, cell adhesion, migration, invasion assays and experimental animal models were carried out to detect the biological functions of Tiam1 in vitro and in vivo. Immunohistochemical analysis revealed that Tiam1 had high expression in 96 of 140 (68.6%) paraffin-embedded archival NPC biopsies. Tiam1 overexpression was significantly associated with N classification (P=0.004), distant metastasis (P=0.042) and clinical stage (P=0.042). Patients with higher levels of Tiam1 expression had poorer overall survival (P=0.002). Multivariate analysis revealed that Tiam1 expression is an independent prognostic indicator for the overall survival of NPC patients. Using the approaches of exogenous overexpression and the knockdown of Tiam1 expression, respectively, it was confirmed that Tiam1 promoted cell proliferation, adhesion, invasion and migration in vitro and in vivo. These data support the notion that Tiam1 plays an important role in the progression of NPC, and the overexpression of Tiam1 is associated with malignant phenotypes of NPC.
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Serum brain-derived neurotrophic factor and nerve growth factor decreased in chronic ketamine abusers.
Drug Alcohol Depend
PUBLISHED: 02-17-2014
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This study investigated the serum levels of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in a group of chronic ketamine abusers in comparison to healthy controls. The correlations between the serum BDNF, NGF level with the subjects' demographic, pattern of ketamine use were also examined.
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Biosorption behavior and mechanism of cesium-137 on Rhodosporidium fluviale strain UA2 isolated from cesium solution.
J Environ Radioact
PUBLISHED: 02-12-2014
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In order to identify a more efficient biosorbent for (137)Cs, we have investigated the biosorption behavior and mechanism of (137)Cs on Rhodosporidium fluviale (R. fluviale) strain UA2, one of the dominant species of a fungal group isolated from a stable cesium solution. We observed that the biosorption of (137)Cs on R. fluviale strain UA2 was a fast and pH-dependent process in the solution composed of R. fluviale strain UA2 (5 g/L) and cesium (1 mg/L). While a Langmuir isotherm equation indicated that the biosorption of (137)Cs was a monolayer adsorption, the biosorption behavior implied that R. fluviale strain UA2 adsorbed cesium ions by electrostatic attraction. The TEM analysis revealed that cesium ions were absorbed into the cytoplasm of R. fluviale strain UA2 across the cell membrane, not merely fixed on the cell surface, which implied that a mechanism of metal uptake contributed largely to the cesium biosorption process. Moreover, PIXE and EPBS analyses showed that ion-exchange was another biosorption mechanism for the cell biosorption of (137)Cs, in which the decreased potassium ions were replaced by cesium ions. All the above results implied that the biosorption of (137)Cs on R. fluviale strain UA2 involved a two-step process. The first step is passive biosorption that cesium ions are adsorbed to cells surface by electrostatic attraction; after that, the second step is active biosorption that cesium ions penetrate the cell membrane and accumulate in the cytoplasm.
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NEDD4L regulates convergent extension movements in Xenopus embryos via Disheveled-mediated non-canonical Wnt signaling.
Dev. Biol.
PUBLISHED: 02-09-2014
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During the early vertebrate body plan formation, convergent extension (CE) of dorsal mesoderm and neurectoderm is coordinated by the evolutionarily conserved non-canonical Wnt/PCP signaling. Disheveled (Dvl), a key mediator of Wnt/PCP signaling, is essential for the medial-lateral polarity formation in the cells undergoing convergent extension movements. NEDD4L, a highly conserved HECT type E3 ligase, has been reported to regulate the stability of multiple substrates including Dvl2. Here we demonstrate that NEDD4L is required for the cellular polarity formation and convergent extension in the early Xenopus embryos. Depletion of NEDD4L in early Xenopus embryos results in the loss of mediolateral polarity of the convergent-extending mesoderm cells and the shortened body axis, resembling those defects caused by the disruption of non-canonical Wnt signaling. Depletion of xNEDD4L also blocks the elongation of the animal explants in response to endogenous mesoderm inducing signals and partially compromises the expression of Brachyury. Importantly, reducing Dvl2 expression can largely rescue the cellular polarity and convergent extension defects in NEDD4L-depleted embryos and explants. Together with the data that NEDD4L reduces Dvl2 protein expression in the frog embryos, our findings suggest that regulation of Dvl protein levels by NEDD4L is essential for convergent extension during early Xenopus embryogenesis.
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Biological correlates of prostate cancer perineural invasion diameter.
Hum. Pathol.
PUBLISHED: 02-06-2014
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Perineural invasion is a symbiotic relationship between cancer cells and nerves and is most frequently seen in "neurotropic" cancers such as prostate cancer. It results in increased perineural space cancer cell growth and decreased apoptosis and induces nerve growth. Tissue microarrays were constructed from 640 radical prostatectomy specimens with prostate cancer. The perineural diameter was measured as previously described. Multiple biomarkers have been previously performed on this tissue microarray cohort, and all data were kept in the same database. The biomarker results database was queried for correlations between perineural invasion diameter and tissue biomarkers. Increased perineural invasion diameter correlated with increased proliferation of prostate cancer cells and with apoptosis. It also correlated with proteins involved in survival pathways such as nuclear factor ?B, c-Myc, phosphorylated AKT, and its downstream effector FHKR, but not with GSK. Unlike nerve density, it did not correlate with decreased PTEN expression. Increased perineural invasion diameter was associated with higher levels of hormonal receptors such as androgen receptor, but not estrogen receptor. Also associated with perineural invasion diameter were coregulators and corepressors including SRC1 and TIF2. Perineural invasion diameter had the strongest correlation with tumor volume (? = 0.579, P = .000), not identified with nerve density. These data demonstrate that perineural invasion has the same biologic correlations as neural density. However, we found a distinct and very strong correlation with increased tumor volume. These data confirm that perineural invasion is the ultimate and most successful interaction between cancer cells and nerve fibers, resulting in increased tumor growth.
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Biologic correlates and significance of axonogenesis in prostate cancer.
Hum. Pathol.
PUBLISHED: 02-06-2014
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Cancer-related axonogenesis and neurogenesis are recently described biologic phenomena. Our previously published data showed that nerve density and the number of neurons in the parasympathetic ganglia are increased in prostate cancer (PCa) and associated with aggressive disease. Tissue microarrays were constructed from 640 radical prostatectomy specimens with PCa. Anti-protein gene product 9.5 (PGP 9.5) antibodies were used to identify and quantify nerve density. Protein expression was objectively analyzed using deconvolution imaging, image segmentation, and image analysis. Data were correlated with clinicopathological variables and tissue biomarkers available in our database. Nerve density, as measured by PGP 9.5 expression, had a weak but significant positive correlation with the lymph node status (? = 0.106; P = .0275). By Cox univariate analysis, PGP 9.5 was a predictor of time to biochemical recurrence, but not on multivariate analysis. Increased nerve density correlated with increased proliferation of PCa cells. It also correlated with expression of proteins involved in survival pathways (Phosphorylated alpha serine/threonine-protein kinase, NF?B, GSK-2, PIM-2, c-Myc, SKP-2, SRF, P27n, PTEN), with increased levels of hormonal regulation elements (androgen receptor, estrogen receptor ?), and coregulators and repressors (SRC-1, SRC-2, AIB-1, DAX). Axonogenesis is a recently described phenomenon of paramount importance in the biology of PCa. Although the degree of axonogenesis is predictive of aggressive behavior in PCa, it does not add to the information present in current models on multivariate analysis. We present data that corroborate that axonogenesis is involved in biologic processes such as proliferation of PCa, through activation of survival pathways and interaction with hormonal regulation.
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Pollen developmental defects in ZD-CMS rice line explored by cytological, molecular and proteomic approaches.
J Proteomics
PUBLISHED: 01-29-2014
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Cytoplasmic male sterility (CMS) is a widely observed phenomenon, which is especially useful in hybrid seed production. Meixiang A (MxA) is a new rice CMS line derived from a pollen-free sterile line named Yunnan ZidaoA (ZD-CMS). In this study, a homologous WA352 gene with variation in two nucleotides was identified in MxA. Cytological analysis revealed that MxA was aborted in the early uninucleate stage. The protein expression profiles of MxA and its maintainer line MeixiangB (MxB) were systematically compared using iTRAQ-based quantitative proteomics technology using young florets at the early uninucleate stage. A total of 688 proteins were quantified in both rice lines, and 45 of these proteins were found to be differentially expressed. Bioinformatics analysis indicated a large number of the proteins involved in carbohydrate metabolism or the stress response were downregulated in MxA, suggesting that these metabolic processes had been hindered during pollen development in MxA. The ROS (reactive oxygen species) level was increased in the mitochondrion of MxA, and further ultrastructural analysis showed the mitochondria with disrupted cristae in the rice CMS line MxA. These findings substantially contribute to our knowledge of pollen developmental defects in ZD-CMS rice line.
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Enhanced resistance to blast fungus in rice (Oryza sativa L.) by expressing the ribosome-inactivating protein ?-momorcharin.
Plant Sci.
PUBLISHED: 01-29-2014
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Rice blast caused by Magnaporthe grisea is one of the three major diseases that seriously affect the rice production. Alpha-momorcharin (?-MC), a ribosome-inactivating protein (RIP) isolated from Momordica charantia seeds, has antifungal effects in vitro. In this study, the ?-MC gene was constitutively expressed under the control of the 2×35S promoter in transgenic rice (Oryza sativa L.) using an Agrobacterium tumefaciens-mediated method. The nine transgenic plants were obtained and confirmed by PCR and RT-PCR, and the four (B2, B4, B7 and B9) of them whose copy numbers were 1, 2, 3 and 3, respectively, were shown to express the ?-MC protein by Western blot. The molecular weight of ?-MC in transgenic plants was approximately 38 kDa larger than the purified ?-MC protein (28 kDa) in vitro. When the confirmed T1 generations were inoculated with a suspension of M. grisea spores for ten days, the lesions on leaves of transgenic plants were much lesser than those found on wild type (WT). According to the criteria of International Rice Research Institute standard, the mean values for morbidity and disease index numbers were 29.8% and 14.9%, respectively, which were lower than for WT. It is unclear whether RIPs could impact plant fitness and however our results suggest that the ?-MC protein is an effective antifungal protein preventing rice blast in transgenic rice.
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Determination of chemical affinity of graphene oxide nanosheets with radionuclides investigated by macroscopic, spectroscopic and modeling techniques.
Dalton Trans
PUBLISHED: 01-22-2014
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The chemical affinity of graphene oxide (GO) nanosheets with radionuclides (Eu(III) and U(VI)) was determined by macroscopic, spectroscopic and modeling techniques. The macroscopic results showed that the adsorption of Eu(III) and U(VI) on GO nanosheets was independent of ionic strength, indicating that inner-sphere surface complexation predominated their adsorption. The maximum adsorption capacities calculated from a Langmuir model at pH 4.0 and T = 303 K were 208.33 mg U(VI) and 28.70 mg Eu(III) per gram of GO nanosheets, respectively. No hysteresis was observed for both Eu(III) and U(VI) on GO nanosheets when desorption was initiated by lowering solution pH. While desorption was induced by replacing the radionuclide supernatant liquid with radionuclide-free electrolyte solution, the adsorption-desorption hysteresis was observed for U(VI) but not for Eu(III), indicating that the chemical affinity of GO nanosheets with U(vi) was stronger than that of GO nanosheets with Eu(III). The adsorption behaviors of Eu(III) and U(VI) on GO nanosheets can be fitted by a double diffuse layer surface complexation model with the mononuclear monodentate >SOM((n-1)+) and >SOMOH((n-2)+) complexes, and larger log K values of U(vi) was observed as compared to those of Eu(iii). According to the spectroscopic analysis, the irreversible adsorption of U(vi) on GO nanosheets at variable radionuclide concentrations was attributed to the oxygen-containing functional groups.
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Association of miR-146a gene polymorphism with risk of nasopharyngeal carcinoma in the central-southern Chinese population.
J. Hum. Genet.
PUBLISHED: 01-16-2014
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This case-control study focused on estimating the association between miR-146a polymorphism and risk of nasopharyngeal carcinoma (NPC) in central-south China. In total, 160 patients with NPC and 200 healthy controls in central-south China were genotyped using polymerase chain reaction-restriction fragment length polymorphism assay. Chi-square test was used to assess the different distribution of miR-146a polymorphism between NPC patients and controls; and logistic regression analysis was applied to analyze the associations between miR-146a polymorphism with cancer risk in different contrast models. Significant differences between NPC patients and controls were found in genotype (P=0.033 for GG versus CG versus CC; and odds ratio (OR)=0.568, 95% confidence interval (CI)=0.354-0.912, P=0.019 for CG versus CC; and OR=0.503, 95% CI=0.261-0.971, P=0.041 for CG versus CC; and OR=0.564, 95% CI=0.360-0.884, P=0.012 for GG+CG versus CC, respectively) and allelic analysis (P=0.025 for G versus C). Our findings suggested that polymorphism of mir-146a was associated with NPC in the central-southern Chinese population.
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How Noise and Language Proficiency Influence Speech Recognition by Individual Non-Native Listeners.
PLoS ONE
PUBLISHED: 01-01-2014
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This study investigated how speech recognition in noise is affected by language proficiency for individual non-native speakers. The recognition of English and Chinese sentences was measured as a function of the signal-to-noise ratio (SNR) in sixty native Chinese speakers who never lived in an English-speaking environment. The recognition score for speech in quiet (which varied from 15%-92%) was found to be uncorrelated with speech recognition threshold (SRTQ/2), i.e. the SNR at which the recognition score drops to 50% of the recognition score in quiet. This result demonstrates separable contributions of language proficiency and auditory processing to speech recognition in noise.
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Cyclin D1 G870A Polymorphism and Risk of Nasopharyngeal Carcinoma: A Case-Control Study and Meta-Analysis.
PLoS ONE
PUBLISHED: 01-01-2014
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Cyclin D1 (CCND1) plays a key role in cell cycle regulation. It is a well-established human oncogene which is frequently amplified or overexpressed in cancers. The association between CCND1 G870A polymorphism and cancer risk has been widely assessed. However, a definitive conclusion between CCND1 G870A polymorphism and risk of nasopharyngeal carcinoma (NPC) remains elusive.
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Transportation of Berberine into HepG2, HeLa and SY5Y Cells: A Correlation to Its Anti-Cancer Effect.
PLoS ONE
PUBLISHED: 01-01-2014
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The anti-cancer activities of berberine (BBR) have been reported extensively in various cancer cell lines. However, the minimal inhibitory concentrations of BBR varied greatly among different cell lines and very few studies have been devoted to elucidate this aspect. In this study, we employed three cancer cell lines, HepG2, HeLa and SY5Y, to compare the transportation and distribution of BBR. HPLC results demonstrated that BBR was capable of penetrating all the cell lines whereas the cumulative concentrations were significantly different. HepG2 cells accumulated higher level of BBR for longer duration than the other two cell lines. Molecular docking studies revealed the BBR binding site on P-glycoprotein 1 (P-gp). In addition, we elucidated that BBR regulated P-gp at both mRNA and protein levels. BBR induced the transcription and translation of P-gp in HeLa and SY5Y cells, whereas BBR inhibited P-gp expression in HepG2 cells. Further study showed that BBR regulates P-gp expression depending on different mechanisms (or affected by different factors) in different cell lines. To summarize, our study has revealed several mechanistic aspects of BBR regulation on P-gp in different cancer cell lines and might shed some useful insights into the use of BBR in the anti-cancer drug development.
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Genome-wide mapping of DNase I hypersensitive sites and association analysis with gene expression in MSB1 cells.
Front Genet
PUBLISHED: 01-01-2014
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DNase I hypersensitive sites (DHSs) mark diverse classes of cis-regulatory regions, such as promoters and enhancers. MSB-1 derived from chicken Marek's disease (MD) lymphomas is an MDV-transformed CD4+ T-cell line for MD study. Previously, DNase I HS sites were studied mainly in human cell types for mammalian. To capture the regulatory elements specific to MSB1 cells and explore the molecular mechanisms of T-cell transformation caused by MDV in MD, we generated high-quality of DHSs map and gene expression profile for functional analysis in MSB1 cell line. The total of 21,724 significant peaks of DHSs was identified from around 40 million short reads. DHSs distribution varied between chromosomes and they preferred to enrich in the gene-rich chromosomes. More interesting, DHSs enrichments appeared to be scarce on regions abundant in CpG islands. Besides, we integrated DHSs into the gene expression data and found that DHSs tended to enrich on high expressed genes throughout whole gene regions while DHSs did not show significant changes for low and silent expressed genes. Furthermore, the correlation of DHSs with lincRNAs expression was also calculated and it implied that enhancer-associated lincRNAs probably originated from enhancer-like regions of DHSs. Together, our results indicated that DNase I HS sites highly correlate with active genes expression in MSB1 cells, suggesting DHSs can be considered as markers to identify the cis-regulatory elements associated with chicken Marek's disease.
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Transport and metabolism behavior of brazilein during its entrance into neural cells.
PLoS ONE
PUBLISHED: 01-01-2014
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Brazilein, a natural small molecule, shows a variety of pharmacological activities, especially on nervous system and immune system. As a potential multifunctional drug, we studied the distribution and the transport behavior and metabolic behavior of brazilein in vivo and in vitro. Brazilein was found to be able to distribute in the mouse brain and transport into neural cells. A metabolite was found in the brain and in the cells. Positive and negative mode-MS/MS and Q-TOF were used to identify the metabolite. MS/MS fragmentation mechanisms showed the methylation occurred at the 10-hydroxyl of brazilein (10-O-methylbrazilein). Further, catechol-O- methyltransferase (COMT) was confirmed as a crucial enzyme correlated with the methylated metabolite generation by molecular docking and pharmacological experiment.
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Distinct breast cancer subtypes in women with early-onset disease across races.
Am J Cancer Res
PUBLISHED: 01-01-2014
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Racial disparities among breast cancer (BCa) patients are known but not well studied in early-onset BCa. We analyzed molecular subtypes in early-onset BCa across five major races.
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CP-673451, a platelet-derived growth-factor receptor inhibitor, suppresses lung cancer cell proliferation and migration.
Onco Targets Ther
PUBLISHED: 01-01-2014
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Lung cancer is the leading cause of cancer mortality in the world. Although some advances in lung cancer therapy have been made, patient survival is still poor. The platelet-derived growth factor receptors (PDGFRs) and their ligands play critical roles in the regulation of many cancer cell processes, including cell survival and cell motility. Herein, we investigate the anticancer activities of CP-673451, a potent selective inhibitor of PDGFR kinase, in non-small-cell lung cancer (NSCLC) therapy. We found that CP-673451 is effective at suppressing cell viability, inducing cell apoptosis, and inhibiting cell migration and invasion by suppressing the PDGFR downstream signaling pathway in NSCLC cells. Furthermore, CP-673451 is effective at suppressing NSCLC tumor growth in vivo. In summary, our studies suggest that CP-673451 might be a promising therapeutic compound for NSCLC.
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Therapeutic effect of TSG-6 engineered iPSC-derived MSCs on experimental periodontitis in rats: a pilot study.
PLoS ONE
PUBLISHED: 01-01-2014
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We derived mesenchymal stem cells (MSCs) from rat induced pluripotent stem cells (iPSCs) and transduced them with tumor necrosis factor alpha-stimulated gene-6 (TSG-6), to test whether TSG-6 overexpression would boost the therapeutic effects of iPSC-derived MSCs in experimental periodontitis.
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Cortical entrainment to continuous speech: functional roles and interpretations.
Front Hum Neurosci
PUBLISHED: 01-01-2014
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Auditory cortical activity is entrained to the temporal envelope of speech, which corresponds to the syllabic rhythm of speech. Such entrained cortical activity can be measured from subjects naturally listening to sentences or spoken passages, providing a reliable neural marker of online speech processing. A central question still remains to be answered about whether cortical entrained activity is more closely related to speech perception or non-speech-specific auditory encoding. Here, we review a few hypotheses about the functional roles of cortical entrainment to speech, e.g., encoding acoustic features, parsing syllabic boundaries, and selecting sensory information in complex listening environments. It is likely that speech entrainment is not a homogeneous response and these hypotheses apply separately for speech entrainment generated from different neural sources. The relationship between entrained activity and speech intelligibility is also discussed. A tentative conclusion is that theta-band entrainment (4-8 Hz) encodes speech features critical for intelligibility while delta-band entrainment (1-4 Hz) is related to the perceived, non-speech-specific acoustic rhythm. To further understand the functional properties of speech entrainment, a splitter's approach will be needed to investigate (1) not just the temporal envelope but what specific acoustic features are encoded and (2) not just speech intelligibility but what specific psycholinguistic processes are encoded by entrained cortical activity. Similarly, the anatomical and spectro-temporal details of entrained activity need to be taken into account when investigating its functional properties.
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Andrographolide suppress tumor growth by inhibiting TLR4/NF-?B signaling activation in insulinoma.
Int. J. Biol. Sci.
PUBLISHED: 01-01-2014
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Insulinomas are rare tumors, and approximately 10% of insulinomas are malignant. Accumulating evidence has implicated that we still lack effective therapy to treat the patients who are diagnosed with rare malignant insulinoma. Previous studies have reported that Andrographolide (Andro) could inhibit cell cycle progression, reduce cell invasion and induce cell apoptosis in many common cancer cells. However, the effects of andro are cell type-dependent. So we emplored the ?-TC-6 cells and the RIP1-Tag2 transgenic mouse model of endogenously growing insulinoma model to elucidate the possible anti-cancer effect of Andro on insulinoma, an uncommon type of malignant cancers in this study. Our experiments revealed that Andro significantly inhibited tumor growth at both the early-stage and the advanced-stage of insulinoma through targeting the TLR4/NF-?B signaling pathway. This work initially provides the evidence that the TLR4/NF-?B signaling pathway might be vital as a potential therapeutic target, and also indispensable in Andro-mediated anti-cancer effect in insulinoma.
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MiR-124 Radiosensitizes human colorectal cancer cells by targeting PRRX1.
PLoS ONE
PUBLISHED: 01-01-2014
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One of the challenges in the treatment of colorectal cancer patients is that these tumors show resistance to radiation. MicroRNAs (miRNAs) are involved in essential biological activities, including chemoresistance and radioresistance. Several research studies have indicated that miRNA played an important role in sensitizing cellular response to ionizing radiation (IR). In this study, we found that miR-124 was significantly down-regulated both in CRC-derived cell lines and clinical CRC samples compared with adjacent non-tumor colorectal tissues, MiR-124 could sensitize human colorectal cancer cells to IR in vitro and in vivo. We identified PRRX1, a new EMT inducer and stemness regulator as a novel direct target of miR-124 by using target prediction algorithms and luciferase assay. PRRX1 knockdown could sensitize CRC cells to IR similar to the effects caused by miR-124. Overexpression of PRRX1 in stably overexpressed-miR-124 cell lines could rescue the effects of radiosensitivity enhancement brought by miR-124. Taking these observations into consideration, we illustrated that miR-124 could increase the radiosensitivity of CRC cells by blocking the expression of PRRX1, which indicated miR-124 could act as a great therapeutic target for CRC patients.
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[Diagnosis and treatment of giant cell tumor of bone in skeletal immature patients].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 12-17-2013
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To demonstrate the common characteristics of giant cell tumor of bone in immature skeletons.
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Optimizing Topographical Templates for Directed Self-Assembly of Block Copolymers via Inverse Design Simulations.
Nano Lett.
PUBLISHED: 12-16-2013
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An inverse design algorithm has been developed that predicts the necessary topographical template needed to direct the self-assembly of a diblock copolymer to produce a given complex target structure. The approach is optimized by varying the number of topographical posts, post size, and block copolymer volume fraction to yield a template solution that generates the target structure in a reproducible manner. The inverse algorithm is implemented computationally to predict post arrangements that will template two different target structures and the predicted templates are tested experimentally with a polydimethylsiloxane-b-polystyrene block copolymer. Simulated and experimental results show overall very good agreement despite the complexity of the patterns. The templates determined from the model can be used in developing simpler design rules for block copolymer directed self-assembly.
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[Grading forecast research for pathogenesis of allergic rhinitis directed by meteorological elements].
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 12-10-2013
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To analyze the correlation between meteorological factors and onset of allergic rhinitis (AR), and to establish the prediction of AR epideminlogical trend.
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[Effect of baicalin on pattern recognition receptor TLR2/4-NOD2 and its significance of druggability].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 11-16-2013
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Activation pattern recognition receptors can cause the startup of downstream signaling pathways, the expression of inflammatory factors, and finally immunological inflammatory reaction. Either exogenous pathogenic microorganisms or endogenous tissue components can activate these pattern recognition receptors as ligands at varying degrees, and then cause the immunological inflammatory reaction. Therefore, it is of great significance to inhibit relevant receptors, as well as the immunological inflammatory reaction, in order to avoid tissue injury during the course of disease. Baicalin is able to specifically inhibit the expression of TLR2/4-NOD2, inhibit the expression of inflammatory factors IL-1beta, IL-6 and TNF-alpha, and thereby reducing the injury of the tissue cells during the course of disease. This effect is non-specific with tissues, which is of great theoretical and practical significance in druggability. In addition, the drug metabolism and toxicity of baicalin are also discussed for its druggability in this article.
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Occurrence and removal efficiency of six polycyclic aromatic hydrocarbons in different wastewater treatment plants.
Water Sci. Technol.
PUBLISHED: 11-05-2013
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Occurrence and removal efficiency of six polycyclic aromatic hydrocarbons (PAHs) (fluoranthene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[ghi]perylene and indeno[1,2,3-cd]pyrene) in wastewater were monitored at different treatment processes in three wastewater treatment plants (WWTPs) by using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Chromatographic separation was performed on a Waters Acquity UPLC BEHC18 column (1.7 ?m, 2.1 mm × 50 mm). A 0.2 ?m precolumn filter was used to protect the analytical column. The result indicated that (1) the total concentrations of six PAHs were 427, 318, and 220 ng L(-1) in the influent of three wastewater treatment plants, respectively. Among six PAHs, the content of fluoranthene was the highest, accounting for 62-66% of total PAHs. (2) Throughout the wastewater treatment process, different treatment units exhibited different removal efficiencies for six PAHs. Biological treatment stage and aerated grit chamber appeared to be necessary for effective removal of six PAHs. The removal efficiencies of six PAHs were 73-83% at biological treatment units, and 24-56% at the aerated grit stage, respectively. The final sedimentation and disinfection for PAH removal was minor.
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Testing Accommodation or Modification? The Effects of Integrated Object Representation on Enhancing Geometry Performance in Children With and Without Geometry Difficulties.
J Learn Disabil
PUBLISHED: 10-28-2013
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According to the National Council of Teachers of Mathematics, geometry and spatial sense are fundamental components of mathematics learning. However, learning disabilities (LD) research has shown that many K-12 students encounter particular geometry difficulties (GD). This study examined the effect of an integrated object representation (IOR) accommodation on the test performance of students with GD compared to students without GD. Participants were 118 elementary students who took a researcher-developed geometry problem solving test under both a standard testing condition and an IOR accommodation condition. A total of 36 students who were classified with GD scored below 40% correct in the geometry problem solving test in the standard testing condition, and 82 students who were classified without GD scored equal to or above 40% correct in the same test and condition. All students were tested in both standard testing condition and IOR accommodation condition. The results from both ANOVA and regression discontinuity (RD) analyses suggested that students with GD benefited more than students without GD from the IOR accommodation. Implications of the study are discussed in terms of providing accommodations for students with mathematics learning difficulties and recommending RD design in LD research.
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Semaphorin 4F as a critical regulator of neuroepithelial interactions and a biomarker of aggressive prostate cancer.
Clin. Cancer Res.
PUBLISHED: 10-04-2013
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Background: Semaphorin 4F (S4F) has roles in embryologic axon guidance and is expressed in adults. S4F is involved in cancer-induced neurogenesis. Methods: Prostate cells were transfected with S4F retrovirus. Cells and controls were used for a bromodeoxyuridine (BrdUrd) incorporation assay (proliferation) and in vitro scratch and Matrigel Transwell chamber invasion assay (migration). Monoclonal antibodies were developed using baculovirus-expressed recombinant GST-S4F and used to immunostain tissue microarrays. Slides were imaged using deconvolution and analyzed using tissue segmentation. Data were correlated with clinicopathologic parameters, other biomarkers and survival analysis conducted. Heterogeneity of S4F expression was analyzed with unsupervised clustering algorithms.
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Rapid detection of AML1 associated fusion genes in patients with adult acute myeloid leukemia and its clinical significance.
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 09-04-2013
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This study was aimed to detect the expression of AML1 fusion genes in the patients with adult acute myeloid leukemia (AML) and further to investigate their association with the progression and prognosis of AML. Bone marrow samples were collected from 168 patients with de novo adult AML, and the expression of AML1 ETO, AML1-EVI1, AML1-MDS1, AML1-MTG16, AML1-PRDM16, AML1-LRP16, AML1-CLCA2 and AML1-PRDX4 was analyzed by a novel multiplex nested RT-PCR. Positive samples and minimal residual disease were further examined by real-time fluorescent quantitative PCR. The results showed that the AML1 fusion genes were found in 10.7% (18/168) patients. Among them, AML1-ETO in 12 (7.1%) cases were detected, AML1-EVI1 in 2 cases (1.2%), and AML1-MDS1, AML1-MTG16, AML1-PRDM16, and AML1-CLCA2 in 1 case (0.6%) each were detected. Among the patients with AML1-ETO, 10 patients (10/12, 83.33%) achieved complete remission (CR) after one cycle of chemotherapy, while 2 patients achieved CR after 2 cycles of chemotherapy. The 2 patients with AML1-EVI1 failed to achieve CR after one cycle of chemotherapy. Patients with AML1-MDS1, AML1-MTG16, AML1-PRDM16, or AML1-CACL2 did not achieve CR after one cycle of chemotherapy. It is concluded that AML1 fusion genes are more frequent and can provide the molecular markers for diagnostics and prognosis evaluation of AML and for monitoring MRD.
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Purgative components in rhubarbs: adrenergic receptor inhibitors linked with glucose carriers.
Fitoterapia
PUBLISHED: 09-01-2013
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Rhubarbs and their extractives have been used as cathartic for many years. There have been numerous breakthroughs in the pharmacological research of the drug. However, as the key point of the mechanism, the targets of the effective components still remain unclear. In this paper, with an in vitro system of isolated intestine, we found that both the rhubarb extractives and the anthraquinone derivatives can antagonize the adrenaline effectively. Furthermore, computer based docking provided the binding model of the anthraquinone derivatives and adrenergic receptor. Then, based on the results of the small intestinal promotion and purgative effect experiments in vivo, we built an "inhibitor-carrier" hypothesis to elucidate the mechanism of rhubarb. This work provided key massages for the pharmacological research of rhubarb, such a common and active medicinal plant, and might be of help for the development of new purgative drugs.
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Microwave photonic phase shifter based on birefringence effects in a semiconductor optical amplifier.
Opt Lett
PUBLISHED: 08-31-2013
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A continuously tunable microwave photonic (MWP) phase shifter based on birefringence effects in a semiconductor optical amplifier (SOA) is presented and the theoretical fundamentals of the design are explained. This proposed device provides a high efficiency phase-shift tuning range beyond 2? rad by controlling the SOA launch power. A prototype of the MWP phase shifter with a frequency of 10 GHz and 2? rad tuning range is experimentally demonstrated.
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Subchondral bone grafting reduces degenerative change of knee joint in patients of giant cell tumor of bone.
Chin. Med. J.
PUBLISHED: 08-29-2013
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Giant cell tumors (GCTs) most commonly occur around the knee. The most beneficial procedure for this disease has been extensive curettage with reconstruction. However, since many GCTs may compromise the subchondral bone, surgery can further jeopardize the articular cartilage and result in secondary osteoarthritis. In this study, we aimed to determine the factors associated with the development of degenerative arthritis and the effect of bone grafting on the prevention of secondary osteoarthritis.
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Membrane protein structure determination: back to the membrane.
Methods Mol. Biol.
PUBLISHED: 08-27-2013
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NMR spectroscopy enables the structures of membrane proteins to be determined in the native-like environment of the phospholipid bilayer membrane. This chapter outlines the methods for membrane protein structural studies using solid-state NMR spectroscopy with samples of membrane proteins incorporated in proteoliposomes or planar lipid bilayers. The methods for protein expression and purification, sample preparation, and NMR experiments are described and illustrated with examples from OmpX and Ail, two bacterial outer membrane proteins that function in bacterial virulence.
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Nanoporous gold as an active low temperature catalyst toward CO oxidation in hydrogen-rich stream.
Sci Rep
PUBLISHED: 08-20-2013
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Preferential CO oxidation (PROX) was investigated by using dealloyed nanoporous gold (NPG) catalyst under ambient conditions. Systematic investigations were carried out to characterize its catalytic performance by varying reaction parameters such as temperature and co-existence of CO2 and H2O, which revealed that NPG was a highly active and selective catalyst for PROX, especially at low temperature. At 20°C, the exit CO concentration could be reduced to less than 2 ppm with a turnover frequency of 4.1 × 10(-2) s(-1) at a space velocity of 120,000 mL h(-1) g(-1)cat. and its high activity could retain for more than 24 hours. The presence of residual Ag species in the structure did not seem to improve the intrinsic activity of NPG for PROX; however, they contributed to the stabilization of the NPG structure and apparent catalytic activity. These results indicated that NPG might be readily applicable for hydrogen purification in fuel cell applications.
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The effect of lansoprazole, an OCT inhibitor, on metformin pharmacokinetics in healthy subjects.
Eur. J. Clin. Pharmacol.
PUBLISHED: 08-19-2013
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Gastro-esophageal reflux disease is common in patients with type 2 diabetes. A common treatment is the co-administration of proton-pump inhibitors (PPIs) and metformin. To date, however, the effects of co-administration of PPIs, which inhibit organic cation transporter (OCT) activity, on the action of metformin (a well-known substrate of OCTs) have not been clearly demonstrated.
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Development and validation of a novel leaky surface acoustic wave immunosensor array for label-free and high-sensitive detection of cyclosporin A in whole-blood samples.
Biosens Bioelectron
PUBLISHED: 08-05-2013
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This manuscript described a novel 2×3 model of leaky surface acoustic wave (LSAW) immunosensor array for label-free and high-sensitive detection of Cyclosporin A (CsA) in whole-blood samples. In this technique, every resonator crystal unit of the LSAW immunosensor array had an individual oscillator circuit to work without mutual interference. The LSAW immunosensor was first immobilized with protein A from Staphylococcus aureus and monoclonal anti-CsA antibody on the gold electrode surface of 100MHz LiTaO3 piezoelectric crystals, which then captured the CsA. The CsA increased the mass loading of LSAW immunosensor and leaded to phase shifts of LSAW. Consequently, under optimal conditions, the designed LSAW immunosensor exhibited a detection limit of 0.89ng/mL, quantification limit of 2.96ng/mL, and wide dynamic linear range from 1ng/mL to 1000ng/mL for CsA detection. Application of the LSAW immunosensor array to clinical sample revealed that consistency and comparability between LSAW immunosensor and the enzyme multiplied immunoassay method were good. Moreover, the immunosensor could be regenerated for ten times without appreciable loss of activity. Therefore, the self-designed LSAW immunosensor array provided a rapid, accurate, label-free, easy handling, and dynamic real-time method for the detection of immunosuppressive drugs in clinical laboratory.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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