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Find video protocols related to scientific articles indexed in Pubmed.
Specific Gene Repression by CRISPRi System Transferred through Bacterial Conjugation.
ACS Synth Biol
PUBLISHED: 11-20-2014
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In microbial communities, bacterial populations are commonly controlled using indiscriminate, broad range antibiotics. There are few ways to target specific strains effectively without disrupting the entire microbiome and local environment. Here we use conjugation, a natural DNA horizontal transfer process among bacterial species, to deliver an engineered CRISPR interference (CRISPRi) system for targeting specific genes in recipient Escherichia coli cells. We show that delivery of the CRISPRi system is successful and can specifically repress a reporter gene in recipient cells, thereby establishing a new tool for gene regulation across bacterial cells and potentially for bacterial population control.
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Endovascular embolization for managing anastomotic bleeding after stapled digestive tract anastomosis.
Acta Radiol
PUBLISHED: 11-20-2014
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Anastomotic bleeding is an infrequent but life-threatening complication after stapled digestive tract anastomosis. Endovascular embolization is one of the available treatments, but precise clinical outcomes are yet to be evaluated.
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Human Phosphoglycerate Dehydrogenase Produces the Oncometabolite d-2-Hydroxyglutarate.
ACS Chem. Biol.
PUBLISHED: 11-19-2014
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Human d-3-phosphoglycerate dehydrogenase (PHGDH), the first enzyme in the serine biosynthetic pathway, is genomically amplified in tumors including breast cancer and melanoma. In PHGDH-amplified cancer cells, knockdown of PHGDH is not fully rescued by exogenous serine, suggesting possible additional growth-promoting roles for the enzyme. Here we show that, in addition to catalyzing oxidation of 3-phosphoglycerate, PHGDH catalyzes NADH-dependent reduction of ?-ketoglutarate (AKG) to the oncometabolite d-2-hydroxyglutarate (d-2HG). Knockdown of PHGDH decreased cellular 2HG by approximately 50% in the PHGDH-amplified breast cancer cell lines MDA-MB-468 (normal concentration 93 ?M) and BT-20 (normal concentration 35 ?M) and overexpression of PHGDH increased cellular 2HG by over 2-fold in non-PHGDH-amplified MDA-MB-231 breast cancer cells, which normally display very low PHGDH expression. The reduced 2HG level in PHGDH knockdown cell lines can be rescued by PHGDH re-expression, but not by a catalytically inactive PHGDH mutant. The initial connection between cancer and d-2HG involved production of high levels of d-2HG by mutant isocitrate dehydrogenase. More recently, however, elevated d-2HG has been observed in breast cancer tumors without isocitrate dehydrogenase mutation. Our results suggest that PHGDH is one source of this d-2HG.
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Inhibition of Transient Receptor Potential Channel 5 Reverses 5-Fluorouracil Resistance in Human Colorectal Cancer Cells.
J. Biol. Chem.
PUBLISHED: 11-19-2014
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5-Fluorouracil (5-Fu) is commonly used in the chemotherapy of colorectal cancer (CRC), but resistance to 5-Fu occurs in most cases, allowing cancer progression. Suppressing ABCB1 (ATP-binding cassette, sub-family B, member1), which is a pump overproduced in cancer cells to export cytotoxic drugs, is an attractive strategy to overcome drug resistance. In the present study, transient receptor potential channel TrpC5 was found to be overproduced at the mRNA and protein levels together with ABCB1 in 5-Fu-resistant human CRC HCT-8 (HCT-8/5-Fu) and LoVo (LoVo/5-Fu) cells. More nuclear-stabilized ?-catenin accumulation was found in HCT-8/5-Fu and LoVo/5-Fu cells than in HCT-8 and LoVo cells. Suppressing TrpC5 expression with TrpC5-specific siRNA inhibited the canonical Wnt/?-catenin signal pathway, reduced the induction of ABCB1, weakened the ABCB1 efflux pump, and caused a remarkable reversal of 5-Fu resistance in HCT-8/5-Fu and LoVo/5-Fu cells. On the contrary, enforcing TrpC5 expression resulted in an activated Wnt/?-catenin signal pathway and up-regulation of ABCB1. Taken together, we demonstrated an essential role of TrpC5 in ABCB1 induction and drug resistance in human CRC cells via promoting nuclear ?-catenin accumulation.
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Sulfur, Trace Nitrogen and Iron Co-doped Hierarchically Porous Carbon Foams as Synergistic Catalysts for Oxygen Reduction Reaction.
ACS Appl Mater Interfaces
PUBLISHED: 11-18-2014
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Sulfur, trace nitrogen and iron co-doped carbon foams with the hierarchically porous structures (HPCFs) were fabricated by directly pyrolysis sulfur-enriched conductive polymer, poly(3,4-ethylenedioxythiphene)-polystyrenesulfonic acid (PEDOT-PSS) aerogels at argon atmosphere. This simple pyrolysis treatment results in the molecular rearrangement of heteroatom sulfur, adjacent carbons and trace nitrogen/iron from oxidants to form active catalytic sites of HPCFs. At the same time, the high porosity of HPCFs provides the large surface area for the uniform distribution of active sites and allows rapid oxygen transport and diffusion. As a result, these HPCFs exhibit the enhanced catalytic performances for oxygen reduction reaction (ORR) in an alkaline electrolyte via a favourable four-electron reduction pathway. Besides, they also display a higher stability and better methanol/CO tolerance than the commercial Pt/C catalyst, which makes them promising low cost, non-precious-metal ORR catalysts for practical application in fuel cells and metal-air batteries.
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Application of sub-Doppler DAVLL to laser frequency stabilization in atomic cesium.
Appl Opt
PUBLISHED: 11-18-2014
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We achieve laser frequency stabilization by a simple technique based on sub-Doppler dichroic atomic vapor laser lock (DAVLL) in atomic cesium. The technique that combines saturated-absorption spectroscopy and Zeeman splitting of hyperfine structures allows us to obtain a modulation-free dispersion-like error signal for frequency stabilization. For the error signal, the dependence of peak-to-peak amplitude and the slope at the zero-crossing point on the magnetic field is studied by simulation and experiment. Based on the result, we obtain an available sub-Doppler DAVLL error signal with high sensitivity to the frequency drift by selecting an appropriate strength of the magnetic field. Ultimately, the fluctuation of the locked laser frequency is confined to below 0.5 MHz in a long term, exhibiting efficient suppression of frequency noise.
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A compensation method for the full phase retardance nonuniformity in phase-only liquid crystal on silicon spatial light modulators.
Opt Express
PUBLISHED: 11-18-2014
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A simple and efficient compensation method for the full correction of both the anisotropic and isotropic nonuniformity of the light phase retardance in a liquid crystal (LC) layer is presented. This is achieved by accurate measurement of the spatial variation of the LC layer's thickness with the help of a calibrated liquid crystal wedge, rather than solely relying on the light intensity profile recorded using two crossed polarizers. Local phase retardance as a function of the applied voltage is calculated with its LC thickness and a set of reference data measured from the intensity of the reflected light using two crossed polarizers. Compensation of the corresponding phase nonuniformity is realized by applying adjusted local voltage signals for different grey levels. To demonstrate its effectiveness, the proposed method is applied to improve the performance of a phase-only liquid crystal on silicon (LCOS) spatial light modulator (SLM). The power of the first diffraction order measured with the binary phase gratings compensated by this method is compared with that compensated by the conventional crossed-polarizer method. The results show that the phase compensation method proposed here can increase the dynamic range of the first order diffraction power significantly from 15~21 dB to over 38 dB, while the crossed-polarizer method can only increase it to 23 dB.
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Effect of dielectric cladding on active plasmonic device based on InGaAsP multiple quantum wells.
Opt Express
PUBLISHED: 11-18-2014
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The Surface Plasmon Polariton (SPP) planar waveguide with amorphous silicon (?-Si) cladding is studied, for empowering the device modulation response. The device is fabricated with multiple quantum wells (MQWs) as the gain media electrically pumped for compensating SPP propagation loss on Au film waveguide. The SPP propagation greatly benefits from the modal gain for the long-range hybrid mode, which is optimized by adopting an ?-Si cladding layer accompanied with minimal degradation of mode confinement. The proposed structure presented more sensitive response to electrical manipulation than the one without cladding in experiment.
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Fabrication and bioactivity evaluation of porous anodised TiO2 films in vitro.
Biosci Trends
PUBLISHED: 11-11-2014
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This study aims to find an optimal method for modifying the neck of dental implants for gingival attachment through in vitro investigations of the biological features of various anodised TiO2 films. The titanium sheets were divided into four groups: a control group and three test groups classified according to the anodisation voltage (Group 150 V, Group 180 V or Group 200 V).The surface microstructure and crystal structure were observed using scanning electron microscopy and X-ray diffraction. The protein adsorption ability, antibacterial activity and cell adhesion ability were tested to examine the biological properties of the materials in vitro. Microscopic grooves were observed in the control group, whereas the test groups contained numerous pores. Group 180 V and Group 200 V showed higher protein adsorption ability (p < 0.05), whereas Group 150 V and Group 180 V exhibited better antibacterial activity (p < 0.05). Higher cell concentrations of L929 were observed in Group 180V and Group 200 V than in the other two groups (p < 0.05), which indicated that the TiO2 films formed at 180 V promote protein adsorption and enhance fibroblast growth while inhibiting bacterial adhesion. These results indicate that anodisation positively affects the formation of a biological seal in the neck region of dental implants.
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Crown ethers attenuate aggregation of amyloid beta of Alzheimer's disease.
Chem. Commun. (Camb.)
PUBLISHED: 11-06-2014
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In this report, we reasoned that non-covalent modification of amyloid beta (A?) by crown ethers could inhibit its aggregation. We demonstrated that PiB-C, a conjugate PiB and crown ether, could significantly reduce the aggregation in vitro. Additionally, two-photon imaging showed that PiB-C could efficiently label A? plaques and CAAs in AD mice.
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A new charging scheme in an emergency department observation unit under Beijing's basic medical insurance.
Chin. Med. J.
PUBLISHED: 10-01-2014
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The new medical insurance policy (JRSYF(2010) No.255) was released by the Beijing Municipal Government and became effective on January 1, 2011. Medical expenses incurred during a stay in an emergency department (ED) observation unit can be reimbursed as a hospital admission. The aim of this study was to evaluate the impact of a new charging scheme during stays in ED observation unit under Beijing's Basic Medical Insurance.
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Balloon dilatation and thrombus extraction for the treatment of cerebral venous sinus thrombosis.
Neurol India
PUBLISHED: 09-20-2014
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This study aimed to investigate the efficacy and safety of balloon dilatation and thrombus extraction for the treatment of cerebral venous sinus thrombosis (CVST).
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1H-NMR metabolite profiles of different strains of Plasmodium falciparum.
Biosci. Rep.
PUBLISHED: 09-02-2014
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Although efforts to understand the basis for inter-strain phenotypic variation in the most virulent malaria species, Plasmodium falciparum, have benefited from advances in genomic technologies, there have to date been few metabolomic studies of this parasite. Using 1H NMR spectroscopy, we have compared the metabolite profiles of red blood cells infected with different P. falciparum strains. These included both chloroquine-sensitive and chloroquine-resistant strains, as well as transfectant lines engineered to express different alleles of the chloroquine-resistance-conferring P. falciparum Chloroquine Resistance Transporter(pfcrt). Our analyses revealed strain-specific differences in a range of metabolites. There was marked variation in the levels of the membrane precursors choline and phosphocholine, with some strains having >30-fold higher choline levels and >5-fold higher phosphocholine levels than others. Chloroquine-resistant strains showed elevated levels of a number of amino acids relative to chloroquine-sensitive strains, including an approximately 2-fold increase in aspartate levels. The elevation in amino acid levels was attributable to mutations in pfcrt. Pfcrt-linked differences in amino acid abundance were confirmed using alternate extraction and detection (HPLC) methods. Mutations acquired to withstand chloroquine exposure therefore give rise to significant biochemical alterations in the parasite.
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Nonpeptidic GLP-1 receptor agonist WB4-24 blocks inflammatory nociception by stimulating ?-endorphin release from spinal microglia.
Br. J. Pharmacol.
PUBLISHED: 09-01-2014
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We recently reported that the glucagon-like peptide-1 receptor (GLP-1R) peptidic agonists exenatide and GLP-1 produced anti-hypersensitive effects in neuropathic, cancer and diabetic pain. In this study, we investigated the anti-allodynic and anti-hyperalgesic effects of the nonpeptidic agonist WB4-24 in inflammatory nociception and possible involvements of microglial ?-endorphin and pro-inflammatory cytokines.
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NK cells kill mycobacteria directly by releasing perforin and granulysin.
J. Leukoc. Biol.
PUBLISHED: 08-19-2014
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Although the mechanisms underlying the cytotoxic effect of NK cells on tumor cells and intracellular bacteria have been studied extensively, it remains unclear how these cells kill extracellular bacterial pathogens. In this study, we examine how human NK cells kill Mycobacterium kansasii and M.tb. The underlying mechanism is contact dependent and requires two cytolytic proteins: perforin and granulysin. Mycobacteria induce enhanced expression of the cytolytic proteins via activation of the NKG2D/NCR cell-surface receptors and intracellular signaling pathways involving ERK, JNK, and p38 MAPKs. These results suggest that NK cells use similar cellular mechanisms to kill both bacterial pathogens and target host cells. This report reveals a novel role for NK cells, perforin, and granulysin in killing mycobacteria and highlights a potential alternative defense mechanism that the immune system can use against mycobacterial infection.
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Macrophage inhibitory cytokine 1 (MIC-1/GDF15) as a novel diagnostic serum biomarker in pancreatic ductal adenocarcinoma.
BMC Cancer
PUBLISHED: 08-08-2014
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Macrophage inhibitory cytokine 1 (MIC-1/GDF15) has been identified as a potential novel biomarker for detection of pancreatic cancer (PCa). However, the diagnostic value of serum MIC-1 for pancreatic ductal adenocarcinoma (PDAC), particularly for those at the early stage, and the value for treatment response monitoring have not yet been investigated.
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Targeting autophagy in skin diseases.
J. Mol. Med.
PUBLISHED: 08-01-2014
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Autophagy is a major intracellular degradative process by which cytoplasmic materials are sequestered in double-membraned vesicles and degraded upon fusion with lysosomes. Under normal circumstances, basal autophagy is necessary to maintain cellular homeostasis by scavenging dysfunctional or damaged organelles or proteins. In addition to its vital homeostatic role, this degradation pathway has been implicated in many different cellular processes such as cell apoptosis, inflammation, pathogen clearance, and antigen presentation and thereby has been linked to a variety of human disorders, including metabolic conditions, neurodegenerative diseases, cancers, and infectious diseases. The skin, the largest organ of the body, serves as the first line of defense against many different environmental insults; however, only a few studies have examined the effect of autophagy on the pathogenesis of skin diseases. This review provides an overview of the mechanisms of autophagy and highlights recent findings relevant to the role of autophagy in skin diseases and strategies for therapeutic modulation.
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Pre-Antiretroviral Therapy Serum Selenium Concentrations Predict WHO Stages 3, 4 or Death but not Virologic Failure Post-Antiretroviral Therapy.
Nutrients
PUBLISHED: 07-28-2014
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A case-cohort study, within a multi-country trial of antiretroviral therapy (ART) efficacy (Prospective Evaluation of Antiretrovirals in Resource Limited Settings (PEARLS)), was conducted to determine if pre-ART serum selenium deficiency is independently associated with human immunodeficiency virus (HIV) disease progression after ART initiation. Cases were HIV-1 infected adults with either clinical failure (incident World Health Organization (WHO) stage 3, 4 or death by 96 weeks) or virologic failure by 24 months. Risk factors for serum selenium deficiency (<85 ?g/L) pre-ART and its association with outcomes were examined. Median serum selenium concentration was 82.04 ?g/L (Interquartile range (IQR): 57.28-99.89) and serum selenium deficiency was 53%, varying widely by country from 0% to 100%. In multivariable models, risk factors for serum selenium deficiency were country, previous tuberculosis, anemia, and elevated C-reactive protein. Serum selenium deficiency was not associated with either clinical failure or virologic failure in multivariable models. However, relative to people in the third quartile (74.86-95.10 ?g/L) of serum selenium, we observed increased hazards (adjusted hazards ratio (HR): 3.50; 95% confidence intervals (CI): 1.30-9.42) of clinical failure but not virologic failure for people in the highest quartile. If future studies confirm this relationship of high serum selenium with increased clinical failure, a cautious approach to selenium supplementation might be needed, especially in HIV-infected populations with sufficient or unknown levels of selenium.
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A least square method based model for identifying protein complexes in protein-protein interaction network.
Biomed Res Int
PUBLISHED: 07-22-2014
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Protein complex formed by a group of physical interacting proteins plays a crucial role in cell activities. Great effort has been made to computationally identify protein complexes from protein-protein interaction (PPI) network. However, the accuracy of the prediction is still far from being satisfactory, because the topological structures of protein complexes in the PPI network are too complicated. This paper proposes a novel optimization framework to detect complexes from PPI network, named PLSMC. The method is on the basis of the fact that if two proteins are in a common complex, they are likely to be interacting. PLSMC employs this relation to determine complexes by a penalized least squares method. PLSMC is applied to several public yeast PPI networks, and compared with several state-of-the-art methods. The results indicate that PLSMC outperforms other methods. In particular, complexes predicted by PLSMC can match known complexes with a higher accuracy than other methods. Furthermore, the predicted complexes have high functional homogeneity.
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Laser Hybrid Micro/nano-structuring of Si Surfaces in Air and its Applications for SERS Detection.
Sci Rep
PUBLISHED: 07-21-2014
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Surface enhanced Raman spectroscopy (SERS) has been widely investigated as an effective technique for low-concentration bio-chemical molecules detection. A rapid two-step approach to fabricate SERS substrates with high controllability in ambient air is developed. Dynamic laser ablation directly creates microgroove on the Si substrate. Meanwhile, nanoparticles are synthesized via the nucleation of laser induced plasma species and the air molecules. It configures the Si surface into four different regions decorated with nanoparticles at different sizes. With Ag film coating, these nanoparticles function as hotspots for SERS. Microsquare arrays are fabricated on the Si surface as large-area SERS substrates by the laser ablation in horizontal and vertical directions. In each microsquare, it exhibits quasi-3D structures with randomly arranged and different shaped nanoparticles aggregated in more than one layer. With Ag film deposition, uniform SERS signals are obtained by detecting the 4-methylbenzenethiol molecules. The SERS signal intensity is determined by the size and shape distributions of the nanoparticles, which depend on the laser processing parameters. With the optimal laser fluence, the SERS signals show a uniform enhancement factor up to 5.5 × 10(6). This provides a high-speed and low-cost method to produce SERS substrates over a large area.
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Variability in Estimated Glomerular Filtration Rate by Area under the Curve Predicts Renal Outcomes in Chronic Kidney Disease.
ScientificWorldJournal
PUBLISHED: 07-16-2014
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Greater variability in renal function is associated with mortality in patients with chronic kidney disease (CKD). However, few studies have demonstrated the predictive value of renal function variability in relation to renal outcomes. This study investigates the predictive ability of different methods of determining estimated glomerular filtration rate (eGFR) variability for progression to renal replacement therapy (RRT) in CKD patients. This was a prospective observational study, which enrolled 1,862 CKD patients. The renal end point was defined as commencement of RRT. The variability in eGFR was measured by the area under the eGFR curve (AUC)%. A significant improvement in model prediction was based on the -2 log likelihood ratio statistic. During a median 28.7-month follow-up, there were 564 (30.3%) patients receiving RRT. In an adjusted Cox model, a smaller initial eGFR AUC%_12M (P < 0.001), a smaller peak eGFR AUC%_12M (P < 0.001), and a larger negative eGFR slope_12M (P < 0.001) were associated with a higher risk of renal end point. Two calculated formulas: initial eGFR AUC%_12M and eGFR slope_12M were the best predictors. Our results demonstrate that the greater eGFR variability by AUC% is associated with the higher risk of progression to RRT.
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The Comparative Study on Expression of SIRT1 Signal Transduction by Xuefuzhuyu Capsule.
Evid Based Complement Alternat Med
PUBLISHED: 07-08-2014
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The Xuefuzhuyu capsule (XFZY) is widely used for the treatment of ischemic heart disease (IHD) in China. We previously demonstrated that XFZY could reduce apoptosis in Sprague-Dawley rat cardiomyocytes with the similar effect of resveratrol (Res) Hori et al. (2013), although its molecular mechanism underlying this protective effect is still unclear. Silent information regulator of transcription 1 (SIRT1) had been demonstrated to be responsible for cardioprotection against ischemia-reperfusion injury via long-term transcriptionally regulatory mechanism Braunersreuther and Jaquet (2012). Therefore, in the present study, we aimed to test if XFZY might contribute to the protection of ischemic myocardial cells induced by ischemia through SIRT1-mediated signal transduction pathway by using electron micrograph, RT-PCR assay, and western-blot test. All the result showed that the target genes of SIRT1 pathway including P53, NF-kB, FOXO1, FOXO3, and FOXO4 were significantly downregulated to SIRT1, suggesting that apoptosis pathway might transcriptionally be regulated to SIRT1. In addition, the expression level of SIRT1 was significantly increased by XFZ, it might prove that SIRT1 is the target of XFZY working on ischemia heart disease. Our findings supported that XFZY might function to protect myocardial cells and reduce myocardial injury though SIRT1 signaling pathway and has the same pharmacological effect with Res.
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DNA methylome profiling of maternal peripheral blood and placentas reveal potential fetal DNA markers for non-invasive prenatal testing.
Mol. Hum. Reprod.
PUBLISHED: 07-04-2014
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Utilizing epigenetic (DNA methylation) differences to differentiate between maternal peripheral blood (PBL) and fetal (placental) DNA has been a promising strategy for non-invasive prenatal testing (NIPT). However, the differentially methylated regions (DMRs) have yet to be fully ascertained. In the present study, we performed genome-wide comparative methylome analysis between maternal PBL and placental DNA from pregnancies of first trimester by methylated DNA immunoprecipitation-sequencing (MeDIP-Seq) and Infinium HumanMethylation450 BeadChip assays. A total of 36 931 DMRs and 45 804 differentially methylated sites (DMSs) covering the whole genome, exclusive of the Y chromosome, were identified via MeDIP-Seq and Infinium 450k array, respectively, of which 3759 sites in 2188 regions were confirmed by both methods. Not only did we find the previously reported potential fetal DNA markers in our identified DMRs/DMSs but also we verified fully the identified DMRs/DMSs in the validation round by MassARRAY EpiTYPER. The screened potential fetal DNA markers may be used for NIPT on aneuploidies and other chromosomal diseases, such as cri du chat syndrome and velo-cardio-facial syndrome. In addition, these potential markers may have application in the early diagnosis of placental dysfunction, such as pre-eclampsia.
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Fabrication of well-ordered binary colloidal crystals with extended size ratios for broadband reflectance.
ACS Appl Mater Interfaces
PUBLISHED: 06-30-2014
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Binary colloidal crystals (BCCs) possess great potentials in tuning material properties by controlling the size ratio of small to large colloidal spheres (?S/L). In this paper, we present a method for the fabrication of BCCs with much more extended size ratios than those obtained in conventional convective self-assembly method. It is found that ?S/L can be extended to 0.376 by adding TEOS sol into the colloidal suspension. The resulting polystyrene/silica (PS/SiO2) BCCs show distinctive reflections, indicating their well-ordered structure. The extended size ratios render more flexibility in engineering the photonic bandgap structures of BCCs and hence provide a better platform for developing a range of applications such as photonics, spintronics, sensing and bioseparation.
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Wnt5A regulates ABCB1 expression in multidrug-resistant cancer cells through activation of the non-canonical PKA/?-catenin pathway.
Oncotarget
PUBLISHED: 06-17-2014
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Multidrug resistance in cancer cells arises from altered drug permeability of the cell. We previously reported activation of the Wnt pathway in ABCB1-overexpressed human uterus sarcoma drug-resistant MES-SA/Dx5 cells through active ?-catenin and associated transactivation activities, and upregulation of Wnt-targeting genes. In this study, Wnt5A was found to be significantly upregulated in MES-SA/Dx5 and MCF7/ADR2 cells, suggesting an important role for the Wnt5A signaling pathway in cancer drug resistance. Higher cAMP response elements and Tcf/Lef transcription activities were shown in the drug-resistant cancer cells. However, expression of Wnt target genes and CRE activities was downregulated in Wnt5A shRNA stably-transfected MES-SA/Dx5 cells. Cell viability of the drug-resistant cancer cells was also reduced by doxorubicin treatment and Wnt5A shRNA transfection, or by Wnt5A depletion. The in vitro data were supported by immunohistochemical analysis of 24 paired breast cancer biopsies obtained pre- and post-chemotherapeutic treatment. Wnt5A, VEGF and/or ABCB1 were significantly overexpressed after treatment, consistent with clinical chemoresistance. Taken together, the Wnt5A signaling pathway was shown to contribute to regulating the drug-resistance protein ABCB1 and ?-catenin-related genes in antagonizing the toxic effects of doxorubicin in the MDR cell lines and in clinical breast cancer samples.
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Clinical efficacy of metallic biliary stents combined with different anti-cancer treatments in the management of bile duct cancer.
Hepatogastroenterology
PUBLISHED: 06-05-2014
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The appropriate selection of an anti-cancer treatment after biliary stenting for bile duct cancer and the effects of new anti-cancer treatments are unclear. To determine the clinical efficacy of metallic biliary stents combined with different anticancer treatments in the management of bile duct cancer.
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Autophagy is required for glucose homeostasis and lung tumor maintenance.
Cancer Discov
PUBLISHED: 05-29-2014
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Macroautophagy (autophagy hereafter) recycles intracellular components to sustain mitochondrial metabolism that promotes the growth, stress tolerance, and malignancy of lung cancers, suggesting that autophagy inhibition may have antitumor activity. To assess the functional significance of autophagy in both normal and tumor tissue, we conditionally deleted the essential autophagy gene, autophagy related 7 (Atg7), throughout adult mice. Here, we report that systemic ATG7 ablation caused susceptibility to infection and neurodegeneration that limited survival to 2 to 3 months. Moreover, upon fasting, autophagy-deficient mice suffered fatal hypoglycemia. Prior autophagy ablation did not alter the efficiency of non-small cell lung cancer (NSCLC) initiation by activation of oncogenic Kras(G12D) and deletion of the Trp53 tumor suppressor. Acute autophagy ablation in mice with preexisting NSCLC, however, blocked tumor growth, promoted tumor cell death, and generated more benign disease (oncocytomas). This antitumor activity occurred before destruction of normal tissues, suggesting that acute autophagy inhibition may be therapeutically beneficial in cancer.
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Suspended microplastics in the surface water of the Yangtze Estuary System, China: first observations on occurrence, distribution.
Mar. Pollut. Bull.
PUBLISHED: 05-22-2014
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Levels of microplastics (MPs) in China are completely unknown. This study characterizes suspended MPs quantitatively and qualitatively for the Yangtze Estuary and East China Sea. MPs were extracted via a floatation method. MPs were counted and categorized according to shape and size under a stereomicroscope. The MP densities were 4137.3±2461.5 and 0.167±0.138 n/m(3), respectively, in the estuarine and the sea samples. Plastic abundances varied significantly in the estuary. Higher densities in three sea trawls confirmed that rivers were the important sources of MP to the marine environment. Plastic particles (>5mm) were observed with a maximum size of 12.46 mm, but MPs (0.5-5 mm) constituted more than 90% by number of items. The most frequent geometries were fibres, followed by granules and films. Plastic spherules occurred sparsely. Transparent and coloured plastics comprised the majority of the particles. This study provides clues in understanding the fate and potential sources of MPs.
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Metal-free oxidative synthesis of quinazolinones via dual amination of sp3 C-H bonds.
Chem. Commun. (Camb.)
PUBLISHED: 05-09-2014
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A novel metal-free synthesis of quinazolinones via dual amination of sp(3) C-H bonds was developed. The sp(3) carbon in methylarenes or adjacent to a heteroatom in DMSO, DMF or DMA was used as the one carbon synthon.
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The personal genome browser: visualizing functions of genetic variants.
Nucleic Acids Res.
PUBLISHED: 05-05-2014
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Advances in high-throughput sequencing technologies have brought us into the individual genome era. Projects such as the 1000 Genomes Project have led the individual genome sequencing to become more and more popular. How to visualize, analyse and annotate individual genomes with knowledge bases to support genome studies and personalized healthcare is still a big challenge. The Personal Genome Browser (PGB) is developed to provide comprehensive functional annotation and visualization for individual genomes based on the genetic-molecular-phenotypic model. Investigators can easily view individual genetic variants, such as single nucleotide variants (SNVs), INDELs and structural variations (SVs), as well as genomic features and phenotypes associated to the individual genetic variants. The PGB especially highlights potential functional variants using the PGB built-in method or SIFT/PolyPhen2 scores. Moreover, the functional risks of genes could be evaluated by scanning individual genetic variants on the whole genome, a chromosome, or a cytoband based on functional implications of the variants. Investigators can then navigate to high risk genes on the scanned individual genome. The PGB accepts Variant Call Format (VCF) and Genetic Variation Format (GVF) files as the input. The functional annotation of input individual genome variants can be visualized in real time by well-defined symbols and shapes. The PGB is available at http://www.pgbrowser.org/.
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The use of natural language processing of infusion notes to identify outpatient infusions.
Pharmacoepidemiol Drug Saf
PUBLISHED: 05-03-2014
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Outpatient infusions are commonly missing in Veterans Health Affairs (VHA) pharmacy dispensing data sets. Currently, Healthcare Common Procedure Coding System (HCPCS) codes are used to identify outpatient infusions, but concerns exist if they correctly capture all infusions and infusion-related data such as dose and date of administration. We developed natural language processing (NLP) software to extract infusion information from medical text infusion notes. The objective was to compare the sensitivity of three approaches to identify infliximab administration dates and infusion doses against a reference standard established from the Veterans Affairs rheumatoid arthritis (VARA) registry.
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Spherical polystyrene-supported chitosan thin film of fast kinetics and high capacity for copper removal.
J. Hazard. Mater.
PUBLISHED: 04-26-2014
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In order to accelerate the kinetics and improve the utilization of the surface active groups of chitosan (CS) for heavy metal ion removal, sub-micron-sized polystyrene supported chitosan thin-film was synthesized by the electrostatic assembly method. Glutaraldehyde was used as cross-linking agent. Chitosan thin-film was well coated onto the surface of the polystyrene (PS) beads characterized by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX). Their adsorption toward Cu(II) ions was investigated as a function of solution pH, degree of cross-linking, equilibrium Cu(II) ions concentration and contact time. The maximum adsorptive capacity of PS-CS was 99.8 mg/g in the adsorption isotherm study. More attractively, the adsorption equilibrium was achieved in 10 min, which showed superior properties among similar adsorbents. Continuous adsorption-desorption cyclic results demonstrated that Cu(II)-loaded PS-CS can be effectively regenerated by a hydrochloric acid solution (HCl), and the regenerated composite beads could be employed for repeated use without significant capacity loss, indicating the good stability of the adsorbents. The XPS analysis confirmed that the adsorption process was due to surface complexes with atoms of chitosan. Generally, PS beads could be employed as a promising host to fabricate efficient composites that originated from chitosan or other bio-sorbents for environmental remediation.
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Copper-catalyzed oxoazidation and alkoxyazidation of indoles.
Org. Lett.
PUBLISHED: 04-15-2014
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Copper-catalyzed oxoazidation and alkoxyazidation of indoles has been developed. The dearomatization reaction which leads to versatile 3-azido indolenine and oxindole derivatives in moderate to good yields could be used in a further transformation.
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Essential role for TrpC5-containing extracellular vesicles in breast cancer with chemotherapeutic resistance.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 04-14-2014
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A critical challenge for chemotherapy is the development of chemoresistance in breast cancer. However, the underlying mechanisms and validated predictors remain unclear. Extracellular vesicles (EVs) have gained attention as potential means for cancer cells to share intracellular contents. In adriamycin-resistant human breast cancer cells (MCF-7/ADM), we analyzed the role of transient receptor potential channel 5 (TrpC5) in EV formation and transfer as well as the diagnostic implications. Up-regulated TrpC5, accumulated in EVs, is responsible for EV formation and trapping of adriamycin (ADM) in EVs. EV-mediated intercellular transfer of TrpC5 allowed recipient cells to acquire TrpC5, consequently stimulating multidrug efflux transporter P-glycoprotein production through a Ca(2+)- and activated T-cells isoform c3-mediated mechanism and thus, conferring chemoresistance on nonresistant cells. TrpC5-containing circulating EVs were detected in nude mice bearing MCF-7/ADM tumor xenografts, and the level was lower after TrpC5-siRNA treatment. In breast cancer patients who underwent chemotherapy, TrpC5 expression in the tumor was significantly higher in patients with progressive or stable disease than in patients with a partial or complete response. TrpC5-containing circulating EVs were found in peripheral blood from patients who underwent chemotherapy but not patients without chemotherapy. Taken together, we found that TrpC5-containing circulating EVs may transfer chemoresistance property to nonchemoresistant recipient cells. It may be worthwhile to further explore the potential of using TrpC5-containing EVs as a diagnostic biomarker for chemoresistant breast cancer.
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Novel method for esophagojejunal anastomosis after laparoscopic total gastrectomy: Semi-end-to-end anastomosis.
World J. Gastroenterol.
PUBLISHED: 04-09-2014
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To test a new safe and simple technique for circular-stapled esophagojejunostomy in laparoscopic total gastrectomy (LATG).
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Direct approaches to nitriles via highly efficient nitrogenation strategy through C-H or C-C bond cleavage.
Acc. Chem. Res.
PUBLISHED: 03-31-2014
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Because of the importance of nitrogen-containing compounds in chemistry and biology, organic chemists have long focused on the development of novel methodologies for their synthesis. For example, nitrogen-containing compounds show up within functional materials, as top-selling drugs, and as bioactive molecules. To synthesize these compounds in a green and sustainable way, researchers have focused on the direct functionalization of hydrocarbons via C-H or C-C bond cleavage. Although researchers have made significant progress in the direct functionalization of simple hydrocarbons, direct C-N bond formation via C-H or C-C bond cleavage remains challenging, in part because of the unstable character of some N-nucleophiles under oxidative conditions. The nitriles are versatile building blocks and precursors in organic synthesis. Recently, chemists have achieved the direct C-H cyanation with toxic cyanide salts in the presence of stoichiometric metal oxidants. In this Account, we describe recent progress made by our group in nitrile synthesis. C-H or C-C bond cleavage is a key process in our strategy, and azides or DMF serve as the nitrogen source. In these reactions, we successfully realized direct nitrile synthesis using a variety of hydrocarbon groups as nitrile precursors, including methyl, alkenyl, and alkynyl groups. We could carry out C(sp(3))-H functionalization on benzylic, allylic, and propargylic C-H bonds to produce diverse valuable synthetic nitriles. Mild oxidation of C?C double-bonds and C?C triple-bonds also produced nitriles. The incorporation of nitrogen within the carbon skeleton typically involved the participation of azide reagents. Although some mechanistic details remain unclear, studies of these nitrogenation reactions implicate the involvement of a cation or radical intermediate, and an oxidative rearrangement of azide intermediate produced the nitrile. We also explored environmentally friendly oxidants, such as molecular oxygen, to make our synthetic strategy more attractive. Our direct nitrile synthesis methodologies have potential applications in the synthesis of biologically active molecules and drug candidates.
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Hymenobacter kanuolensis sp. nov., a novel radiation-resistant bacterium.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 03-28-2014
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A Gram-reaction-negative, rod-shaped, non-motile, red-pigmented, radiation-resistant, aerobic bacterium designated T-3(T) was isolated from a soil sample from the Qinghai-Tibet Plateau in Tibet, China, after exposure to 10 kGy gamma radiation. Phylogenetic analysis based on 16S rRNA sequences indicated that this isolate represented a novel member of the genus Hymenobacter. Sequence identities of the 16S rRNA gene of strain T-3(T) with the type strains of species of the genus Hymenobacter with validly published names range from 89% to 97%, and the most closely related species is Hymenobacter psychrotolerans Tibet-IIU11(T) (97%). The DNA-DNA relatedness between strain T-3(T) and H. psychrotolerans is 59.10%. The major fatty acids of strain T-3(T) were iso-C(15?:?0) (27.66%), summed feature 4 (iso-C(17?:?1)I and/or anteiso-C(17?:?1)B, 15.84%), anteiso-C(15?:?0) (14.08%) and summed feature 3 (C(16?:?1)?7c and/or C(16?:?1)?6c, 12.38%). The major menaquinone of strain T-3(T) was MK-7. Phosphatidylethanolamine (PE) was predominant in the polar lipid profile. The G+C content of the DNA of strain T-3(T) was 69.17 mol%. On the basis of the results of the polyphasic characterization presented in this study, it is concluded that strain T-3(T) represents a novel species of the genus Hymenobacter, for which the name Hymenobacter kanuolensis is proposed. The type strain is T-3(T) (?=?ACCC 05760(T)?=?KCTC 32407(T)).
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Response surface optimized extraction of 1-deoxynojirimycin from mulberry leaves (Morus alba L.) and preparative separation with resins.
Molecules
PUBLISHED: 03-26-2014
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In the present study, the extraction technology and preparative separation of 1-deoxynojirimycin from mulberry leaves were systematically investigated. Four extraction parameters (ethanol concentration, extraction temperature, extraction time and ratio of solvent to sample) were explored by response surface methodology (RSM). The results indicated that the maximal yield of 1-deoxynojirimycin was achieved with an ethanol concentration of 55%, extraction temperature of 80 °C, extraction time of 1.2 h and ratio of solvent to sample of 12:1. The extraction yield under these optimum conditions was found to be 256 mg/100 g dry mulberry leaves. A column packed with a selected resin was used to perform dynamic adsorption and desorption tests to optimize the separation process. The results show that the preparative separation of 1-deoxynojirimycin from mulberry leaves can be easily and effectively done by adopting 732 resin. In conclusion, 732 resin is the most appropriate for the separation of 1-deoxynojirimycin from other components in mulberry leaves extracts, and its adsorption behavior can be described with Langmuir isotherms and a two-step adsorption kinetics model. The recovery and purity of 1-deoxynojirimycin in the final product were 90.51% and 15.3%, respectively.
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Curcumin-induced melanoma cell death is associated with mitochondrial permeability transition pore (mPTP) opening.
Biochem. Biophys. Res. Commun.
PUBLISHED: 03-25-2014
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Here we studied the role of mitochondrial permeability transition pore (mPTP) opening in curcumin's cytotoxicity in melanoma cells. In cultured WM-115 melanoma cells, curcumin induced mitochondrial membrane potential (MPP) decrease, cyclophilin-D (CyPD)-adenine nucleotide translocator 1 (ANT-1) (two mPTP components) mitochondrial association and cytochrome C release, indicating mPTP opening. The mPTP blocker sanglifehrin A (SfA) and ANT-1 siRNA-depletion dramatically inhibited curcumin-induced cytochrome C release and WM-115 cell death. CyPD is required for curcumin-induced melanoma cell death. The CyPD inhibitor cyclosporin A (CsA) or CyPD siRNA-depletion inhibited curcumin-induced WM-115 cell death and apoptosis, while WM-115 cells with CyPD over-expression were hyper-sensitive to curcumin. Finally, we found that C6 ceramide enhanced curcumin-induced cytotoxicity probably through facilitating mPTP opening, while CsA and SfA as well as CyPD and ANT-1 siRNAs alleviated C6 ceramide's effect on curcumin in WM-115 cells. Together, these results suggest that curcumin-induced melanoma cell death is associated with mPTP opening.
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Documentation of delirium in the VA electronic health record.
BMC Res Notes
PUBLISHED: 03-25-2014
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Delirium is a life-threatening, clinical syndrome common among the elderly and hospitalized patients. Delirium is under-recognized and misdiagnosed, complicating efforts to study the epidemiology and construct appropriate decision support to improve patient care. This study was primarily conducted to realize how providers documented confirmed cases of delirium in electronic health records as a preliminary step for using computerized methods to identify patients with delirium from electronic health records.
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Mapping of hepatic expression quantitative trait loci (eQTLs) in a Han Chinese population.
J. Med. Genet.
PUBLISHED: 03-24-2014
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Elucidating the genetic basis underlying hepatic gene expression variability is of importance to understand the aetiology of the disease and variation in drug metabolism. To date, no genome-wide expression quantitative trait loci (eQTLs) analysis has been conducted in the Han Chinese population, the largest ethnic group in the world.
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Preparation of uniform magnetic recoverable catalyst microspheres with hierarchically mesoporous structure by using porous polymer microsphere template.
Nanoscale Res Lett
PUBLISHED: 03-21-2014
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Merging nanoparticles with different functions into a single microsphere can exhibit profound impact on various applications. However, retaining the unique properties of each component after integration has proven to be a significant challenge. Our previous research demonstrated a facile method to incorporate magnetic nanoparticles into porous silica microspheres. Here, we report the fabrication of porous silica microspheres embedded with magnetic and gold nanoparticles as magnetic recoverable catalysts. The as-prepared multifunctional composite microspheres exhibit excellent magnetic and catalytic properties and a well-defined structure such as uniform size, high surface area, and large pore volume. As a result, the very little composite microspheres show high performance in catalytic reduction of 4-nitrophenol, special convenient magnetic separability, long life, and good reusability. The unique nanostructure makes the microspheres a novel stable and highly efficient catalyst system for various catalytic industry processes.
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n-Bu?NI-catalyzed selective dual amination of sp³ C-H bonds: oxidative domino synthesis of imidazo[1,5-c]quinazolines on a gram-scale.
Chem. Commun. (Camb.)
PUBLISHED: 03-19-2014
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An n-Bu4NI catalyzed domino reaction that involves selective dual amination of sp(3) C-H bonds has been developed. The protocol affords a facile and efficient approach to the synthesis of imidazo[1,5-c]quinazolines under mild conditions.
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Manipulating DC currents with bilayer bulk natural materials.
Adv. Mater. Weinheim
PUBLISHED: 03-18-2014
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A novel and general method for spatially manipulating DC currents has been proposed and experimentally verified by only using bilayer bulk natural conductive materials. Our approach shows distinctive advantages with respect to homogeneity, isotropy, and independence of complicated microfabrication techniques. Our design scheme can be readily extended to robust manipulations of magnetic fields, thermal heat, elastic mechanics, and matter waves.
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Tetramethylpyrazine promotes the proliferation and migration of brain endothelial cells.
Mol Med Rep
PUBLISHED: 03-17-2014
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The aim of the present study was to investigate the role of tetramethylpyrazine (TMP), one of the alkaloids isolated from the Chinese herb Chuanxiong, on the proliferation and migration of brain endothelial cells. A different dosage of TMP was employed to stimulate the mouse microvascular cell line bEnd.3 in vitro. TMP at lower concentrations (0.25 ng/ml), however not at high concentrations (100 ng/ml) could promote the proliferation and migration of endothelial cells, which was further enhanced if combined with soluble Fas ligand (sFasL). TMP alone, or combined with sFasL, increased the autocrine signaling of vascular endothelial growth factor (VEGF) by endothelial cells and TMP improved the expression of Fas on endothelial cells, which may explain the effect of the sFasL. These results provide insight into the underlying mechanisms of the effects of TMP on stroke and other vascular diseases.
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Computational prediction of protein function based on weighted mapping of domains and GO terms.
Biomed Res Int
PUBLISHED: 03-12-2014
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In this paper, we propose a novel method, SeekFun, to predict protein function based on weighted mapping of domains and GO terms. Firstly, a weighted mapping of domains and GO terms is constructed according to GO annotations and domain composition of the proteins. The association strength between domain and GO term is weighted by symmetrical conditional probability. Secondly, the mapping is extended along the true paths of the terms based on GO hierarchy. Finally, the terms associated with resident domains are transferred to host protein and real annotations of the host protein are determined by association strengths. Our careful comparisons demonstrate that SeekFun outperforms the concerned methods on most occasions. SeekFun provides a flexible and effective way for protein function prediction. It benefits from the well-constructed mapping of domains and GO terms, as well as the reasonable strategy for inferring annotations of protein from those of its domains.
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Toxoplasma gondii induce apoptosis of neural stem cells via endoplasmic reticulum stress pathway.
Parasitology
PUBLISHED: 03-10-2014
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Toxoplasma gondii is a major cause of congenital brain disease; however, the underlying mechanism of neuropathogenesis in brain toxoplasmosis remains elusive. To explore the role of T. gondii in the development of neural stem cells (NSCs), NSCs were isolated from GD14 embryos of ICR mice and were co-cultured with tachyzoites of T. gondii RH strain. We found that apoptosis levels of the NSCs co-cultured with 1×106 RH tachyzoites for 24 and 48 h significantly increased in a dose-dependent manner, as compared with the control. Western blotting analysis displayed that the protein level of C/EBP homologous protein (CHOP) was up-regulated, and caspase-12 and c-Jun N-terminal kinase (JNK) were activated in the NSCs co-cultured with the parasites. Pretreatment with endoplasmic reticulum stress (ERS) inhibitor (TUDCA) and caspase-12 inhibitor (Z-ATAD-FMK) inhibited the expression or activation of the key molecules involved in the ERS-mediated apoptotic pathway, and subsequently decreased the apoptosis levels of the NSCs induced by the T. gondii. The findings here highlight that T. gondii induced apoptosis of the NSCs through the ERS signal pathway via activation of CHOP, caspase-12 and JNK, which may constitute a potential molecular mechanism responsible for the cognitive disturbance in neurological disorders of T. gondii.
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Antidepressant-like effects and mechanism of action of SYG in depression model in rats.
Neuro Endocrinol. Lett.
PUBLISHED: 03-09-2014
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The present study aimed to evaluate whether SYG, a Chinese herbal formula, could produce antidepressant-like effects in learned helplessness (LH) model and chronic mild stress (CMS) model in rats. The mechanism underlying the antidepressant-like action was investigated by exploring BDNF signaling way in the hippocampus.
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The medicinal fungus Antrodia cinnamomea suppresses inflammation by inhibiting the NLRP3 inflammasome.
J Ethnopharmacol
PUBLISHED: 03-09-2014
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Antrodia cinnamomea--a medicinal fungus that is indigenous to Taiwan--has been used as a health tonic by aboriginal tribes and the Asian population. Recent studies indicate that Antrodia cinnamomea extracts exhibit hepato-protective, anti-hypertensive, anti-oxidative, anti-inflammatory, immuno-modulatory, and anti-cancer effects on cultured cells and laboratory animals. This study aims to explore the anti-inflammatory activity of an Antrodia cinnamomea ethanol extract (ACEE) and elucidate its underlying mechanisms of action using lipopolysaccharide (LPS)-primed, ATP-stimulated human THP-1 macrophages.
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Resveratrol triggers protective autophagy through the ceramide/Akt/mTOR pathway in melanoma B16 cells.
Nutr Cancer
PUBLISHED: 02-28-2014
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Resveratrol (3,5,4'-trihydroxy-trans-stilbene, RSV), a natural polyphenolic compound, is known as a promising anti-cancer agent. In this study, we showed that RSV could inhibit the growth of B16 cells via induction of apoptosis. Moreover, our results showed for the first time that RSV induced autophagy in B16 cells, which might occur through ceramide accumulation and Akt/mTOR pathway inhibition. Inhibition of autophagy by an autophagic inhibitor 3-methyladenine (3-MA) or si-Beclin 1 enhanced RSV-induced cytotoxicity and apoptosis. Thus, autophagy inhibition represents a promising approach to improve the efficacy of RSV in the treatment of patients with melanoma.
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Ki-67 is a valuable prognostic predictor of lymphoma but its utility varies in lymphoma subtypes: evidence from a systematic meta-analysis.
BMC Cancer
PUBLISHED: 02-24-2014
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Ki-67 is a nuclear protein involved in cell proliferation regulation, and its expression has been widely used as an index to evaluate the proliferative activity of lymphoma. However, its prognostic value for lymphoma is still contradictory and inconclusive.
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Dose response and clonal variability of lentiviral tetracycline-regulated vectors in murine hematopoietic cells.
Exp. Hematol.
PUBLISHED: 02-23-2014
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Tetracycline-regulated integrating vectors allow pharmacologically controlled genetic modification of murine and human hematopoietic stem cells and provide the opportunity for time- and dose-controlled reversible transgene expression in hematopoietic stem cells in vitro and in vivo. However, the background activity of tetracycline-regulated promoters (tetPs) in the absence of induction or vector integration in the vicinity of proto-oncogenes can diminish the advantages of the system. Here we investigated the effect of lentiviral transduction rate on tetP background activity, vector copy number (VCN), and clonal variability as a consequence of vector integration. We found an exponential relationship between VCN and gene transfer/expression level, accompanied by a linear relationship between VCN and tetP background activity. Long-term murine transplantation studies demonstrated stable and reversible transgene expression in serial recipients. Although analysis of associated clonal composition revealed development of clonal dominance in the presence and absence of induction, no indications of disease presented during the observation period. The majority of tetracycline-regulated vector integration sites were identified in intron/exons of metabolic/housekeeping and signaling genes or in noncoding/repeat regions of the genome. Furthermore, we demonstrated that the nature of the selected transgene might affect tetP background activity and inducibility in vivo. Limiting tetP-regulated gene transfer may avoid generation of clones with high VCN and enhanced tetP background activity. Our data help to establish physiologic and pathophysiologic systems to study dose-dependent mechanisms triggered by different levels of transgene expression in the context of basic HSC biology and cellular transformation models.
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Criteria-specific long-term survival prediction model for hepatocellular carcinoma patients after liver transplantation.
World J. Gastroenterol.
PUBLISHED: 02-15-2014
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To establish a model to predict long-term survival of hepatocellular carcinoma (HCC) patients after liver transplantation (MHCAT).
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Surgical strategy for isolated caudate lobectomy: experience with 16 cases.
HPB Surg
PUBLISHED: 02-15-2014
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Introduction. Surgical resection is the most effective treatment for neoplasm in the caudate lobe. Isolated caudate lobectomy is still a challenge for hepatobiliary surgeons. No widely accepted surgical strategy for the procedure has been developed yet. Objective. To get a better understanding of isolated caudate lobectomy and to optimize the procedure. Materials and Methods. 16 cases of isolated caudate lobectomy were reviewed to summarize the surgical experience. Results. All the 16 cases of isolated caudate lobectomy were carried out successfully, among which left side approach was adopted in two cases (12.5%), right side approach in three cases (18.75%), and both sides approach in 11 cases (68.75%). No severe complications occurred. Conclusion. The majority of neoplasms confined to the caudate lobe can be resected safely by left and right side approach with proper anatomic surgical procedure, usually in the sequence of mobilization, outflow control, inflow control, and division of the hepatic parenchyma. Fully mobilizing the caudate lobe from the inferior vena cava (IVC) is of great importance. Division of the retrohepatic ligament and the venous ligament facilitated the procedure.
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MiR-489 regulates chemoresistance in breast cancer via epithelial mesenchymal transition pathway.
FEBS Lett.
PUBLISHED: 02-13-2014
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To investigate the role of microRNAs in the development of chemoresistance and related epithelial-mesenchymal transition (EMT), we examined the effect of miR-489 in adriamycin (ADM)-resistant human breast cancer cells (MCF-7/ADM). MiR-489 was significantly suppressed in MCF-7/ADM cells compared with chemosensitive parental control MCF-7/WT cells. Forced-expression of miR-489 reversed chemoresistance. Furthermore, Smad3 was identified as the target of miR-489 and is highly expressed in MCF-7/ADM cells. Forced expression of miR-489 both inhibited Smad3 expression and Smad3 related EMT properties. Finally, the interactions between Smad3, miR-489 and EMT were confirmed in chemoresistant tumor xenografts and clinical samples, indicating their potential implication for treatment of chemoresistance.
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Nonreciprocal optical diffraction by a single layer of gyromagnetic cylinders.
Opt Express
PUBLISHED: 02-12-2014
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We study the diffraction of optical waves by a single layer of gyromagnetic cylinders. We show that a nonvanishing rotating dipole momentum is excited in a single gyromagnetic cylinder because of the classic analog of the Zeeman effect on photonic angular momentum states (PAMSs). Consequently, different collective dipole modes are excited in a gyromagnetic cylinder array at opposite incident angles. Nonreciprocal optical diffraction effects can be observed, where the transmission and reflection coefficients depend on the sign of the incident angle. A novel phenomenon of nonreciprocal negative directional transmission is demonstrated and numerically analyzed. This work highlights the potential of PAMSs in manipulating the propagation of optical waves for various applications.
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Morphology modulation of SrTiO3/TiO2 heterostructures for enhanced photoelectrochemical performance.
J Colloid Interface Sci
PUBLISHED: 02-05-2014
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Design and fabrication of nanoscale semiconductors with regulatable morphology or structure has attracted tremendous interest due to the dependency relationship between properties and architectures. Two types of SrTiO3/TiO2 nanocomposites with different morphologies and structures have been fabricated by controlling the kinetics of hydrothermal reactions. One is TiO2 nanotube arrays densely wrapped by SrTiO3 film and the other is SrTiO3 nanospheres distributed on the top region of TiO2 nanotube arrays, which has been firstly fabricated. It has been found that the photoelectrochemical performances of these heterostructures are crucially dominated by their architectures. Heterostructured SrTiO3/TiO2 nanotube arrays were fabricated by traditional method in the absence of NaOH and they exhibited higher photoelectrochemical performance than pure TiO2 nanotube arrays. However, the compact SrTiO3 coating film on the sidewalls of TiO2 nanotube arrays could inevitably destroy the tubular structures of TiO2 and thus go against the vectorial transport of electrons. Interestingly, when excess NaOH was added into the growth solution, SrTiO3 nanospheres would be rationally grafted on the top of TiO2 nanotube arrays, which could preserve the tubular structures of TiO2, and thus further improve the photoelectrochemical performance.
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Creation of vectorial bottle-hollow beam using radially or azimuthally polarized light.
Opt Lett
PUBLISHED: 02-04-2014
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We propose a single-beam generation scheme to obtain a bottle-hollow (BH) beam using a binary phase mask and a focusing lens. The resulting BH beam is shown to possess an open bottle-shaped null intensity region, which has two hollow tube-shaped null intensity regions located on two opposite sides of this bottle. It is found that this scheme works identically under incident illumination with radial or azimuthal polarization. Another advantage of this scheme is that the same binary mask can be employed as a focusing lens with different choices of numerical aperture (NA). Furthermore, we observe that the length of the BH beam is inversely proportional to NA2 while the diameters of both the bottle and hollow regions are inversely proportional to NA; thereby leading to an adjustable BH beam. This BH beam may find attractive applications in noninvasive manipulation of microscopic particles over large distances.
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Fabrication of monodisperse porous zirconia microspheres and their phosphorylation for Friedel-Crafts alkylation of indoles.
ACS Appl Mater Interfaces
PUBLISHED: 02-04-2014
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Monodisperse porous zirconia (ZrO2) microspheres with nanocrystallized framework were fabricated by impregnation of porous polymer microspheres as a novel hard template with zirconia precursors followed by calcination to remove the template. Porous phosphorylated zirconia (PhZr) microspheres were prepared by further treating porous zirconia microspheres with phosphoric acid. The morphology, structure, and properties of these microspheres were studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption/desorption measurement, FT-IR, and X-ray powder diffraction. The as-prepared zirconia and phosphorylated zirconia microspheres showed uniform particle size and well-defined morphology. The phosphorylated zirconia microspheres served as highly active solid acid catalysts for Friedel-Crafts alkylation of indoles with chalcones and could be reused for 22 cycles with negligible loss of activity. In situ pyridine-adsorbed FT-IR analysis of the best performing PhZr microspheres suggested the presence of both Lewis and Brønsted acid sites, and the total acidity as measured by temperature-programmed desorption of ammonia (NH3-TPD) was 328 ?mol·g(-1).
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Expression of stromal cell-derived factor 1 and CXCR7 ligand receptor system in pancreatic adenocarcinoma.
World J Surg Oncol
PUBLISHED: 02-01-2014
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Stromal cell-derived factor 1 (SDF-1) is a chemokine that is expressed in some cancer cells and is involved in tumor cell migration and metastasis. CXCR7, a novel receptor for SDF-1, has been identified recently. Research has demonstrated that SDF-1/CXCR7 interaction could play an important role in cancer progression. In this study, we aimed to investigate the expression of the SDF-1/CXCR7 ligand receptor system and the relationship between this expressions and clinicopathological characteristics in pancreatic adenocarcinoma.
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Rutin improves spatial memory in Alzheimer's disease transgenic mice by reducing A? oligomer level and attenuating oxidative stress and neuroinflammation.
Behav. Brain Res.
PUBLISHED: 01-30-2014
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Alzheimer's disease (AD) is a progressive, neurodegenerative disease characterized by extracellular ?-amyloid (A?) plaques and intracellular neurofibrillary tangles in the brain. A? aggregation is closely associated with neurotoxicity, oxidative stress, and neuronal inflammation. The soluble A? oligomers are believed to be the most neurotoxic form among all forms of A? aggregates. We have previously reported a polyphenol compound rutin that could inhibit A? aggregation and cytotoxicity, attenuate oxidative stress, and decrease the production of nitric oxide and proinflammatory cytokines in vitro. In the current study, we investigated the effect of rutin on APPswe/PS1dE9 transgenic mice. Results demonstrated that orally administered rutin significantly attenuated memory deficits in AD transgenic mice, decreased oligomeric A? level, increased super oxide dismutase (SOD) activity and glutathione (GSH)/glutathione disulfide (GSSG) ratio, reduced GSSG and malondialdehyde (MDA) levels, downregulated microgliosis and astrocytosis, and decreased interleukin (IL)-1? and IL-6 levels in the brain. These results indicated that rutin is a promising agent for AD treatment because of its antioxidant, anti-inflammatory, and reducing A? oligomer activities.
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Compound Formula Rehmannia alleviates levodopa-induced dyskinesia in Parkinson's disease.
Neural Regen Res
PUBLISHED: 01-18-2014
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Compound Formula Rehmannia has been shown to be clinically effective in treating Parkinson's disease and levodopa-induced dyskinesia; however, the mechanisms remain unclear. In this study, we established a model of Parkinson's disease dyskinesia in rats, and treated these animals with Compound Formula Rehmannia. Compound Formula Rehmannia inhibited the increase in mRNA expression of N-methyl-D-aspartate receptor subunits 1 and 2 and excitatory amino acid neurotransmitter genes, and it inhibited the reduction in expression of ?-aminobutyric acid receptor B1, an inhibitory amino acid neurotransmitter gene, in the corpus striatum. In addition, Compound Formula Rehmannia alleviated dyskinesia symptoms in the Parkinson's disease rats. These experimental findings indicate that Compound Formula Rehmannia alleviates levodopa-induced dyskinesia in Parkinson's disease by modulating neurotransmitter signaling in the corpus striatum.
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One step preparation of a high performance Ge-C nanocomposite anode for lithium ion batteries by tandem plasma reactions.
Chem. Commun. (Camb.)
PUBLISHED: 01-15-2014
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We employ a tandem plasma reaction method to prepare ultrafine Ge nanoparticles embedded in a carbon matrix in one step. The obtained Ge-C composite exhibits very high lithium storage capacity (980 mA h g(-1)) and excellent cycling performance (less than 2% capacity loss in 100 cycles).
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Maternal pneumococcal capsular IgG antibodies and transplacental transfer are low in South Asian HIV-infected mother-infant pairs.
Vaccine
PUBLISHED: 01-14-2014
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Our understanding of the mother-to-child transfer of serotype-specific pneumococcal antibodies is limited in non-immunized, HIV-positive women.
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The synthesis, characterization and optical properties of novel 5-(3-aryl-1H-pyrazol-5-yl)-2-(3-butyl-1-chloroimidazo[1,5-a]pyridin-7-yl)-1,3,4-oxadiazole.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 01-14-2014
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A series of novel 5-(3-aryl-1H-pyrazol-5-yl)-2-(3-butyl-1-chloroimidazo[1,5-a]- pyridin-7-yl)-1,3,4-oxadiazole derivatives has been synthesized from 3-butyl-1-chloroimidazo[1,5-a]pyridine-7-carboxylic acid and ethyl 3-aryl-1H-pyrazole-5-carboxylate. The compounds were characterized using IR, (1)H NMR, HRMS and UV-vis absorption. The fluorescence spectral characteristics of the compounds in dichloromethane were investigated. The results showed that absorption ?max and emission ?max was less correlated with substituent groups on N-1 position of pyrazole moiety and para position of benzene moiety. The calculated molecular orbital correlates well with their absorption.
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Gender-related barriers and delays in accessing tuberculosis diagnostic and treatment services: a systematic review of qualitative studies.
Tuberc Res Treat
PUBLISHED: 01-12-2014
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Background. Tuberculosis (TB) remains a significant global public health problem with known gender-related (male versus female) disparities. We reviewed the qualitative evidence (written/spoken narrative) for gender-related differences limiting TB service access from symptom onset to treatment initiation. Methods. Following a systematic process, we searched 12 electronic databases, included qualitative studies that assessed gender differences in accessing TB diagnostic and treatment services, abstracted data, and assessed study validity. Using a modified "inductive coding" system, we synthesized emergent themes within defined barriers and delays limiting access at the individual and provider/system levels and examined gender-related differences. Results. Among 13,448 studies, 28 studies were included. All were conducted in developing countries and assessed individual-level barriers; 11 (39%) assessed provider/system-level barriers, 18 (64%) surveyed persons with suspected or diagnosed TB, and 7 (25%) exclusively surveyed randomly sampled community members or health care workers. Each barrier affected both genders but had gender-variable nature and impact reflecting sociodemographic themes. Women experienced financial and physical dependence, lower general literacy, and household stigma, whereas men faced work-related financial and physical barriers and community-based stigma. Conclusions. In developing countries, barriers limiting access to TB care have context-specific gender-related differences that can inform integrated interventions to optimize TB services.
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Barriers and delays in tuberculosis diagnosis and treatment services: does gender matter?
Tuberc Res Treat
PUBLISHED: 01-12-2014
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Background. Tuberculosis (TB) remains a global public health problem with known gender-related disparities. We reviewed the quantitative evidence for gender-related differences in accessing TB services from symptom onset to treatment initiation. Methods. Following a systematic review process, we: searched 12 electronic databases; included quantitative studies assessing gender differences in accessing TB diagnostic and treatment services; abstracted data; and assessed study validity. We defined barriers and delays at the individual and provider/system levels using a conceptual framework of the TB care continuum and examined gender-related differences. Results. Among 13,448 articles, 137 were included: many assessed individual-level barriers (52%) and delays (42%), 76% surveyed persons presenting for care with diagnosed or suspected TB, 24% surveyed community members, and two-thirds were from African and Asian regions. Many studies reported no gender differences. Among studies reporting disparities, women faced greater barriers (financial: 64% versus 36%; physical: 100% versus 0%; stigma: 85% versus 15%; health literacy: 67% versus 33%; and provider-/system-level: 100% versus 0%) and longer delays (presentation to diagnosis: 45% versus 0%) than men. Conclusions. Many studies found no quantitative gender-related differences in barriers and delays limiting access to TB services. When differences were identified, women experienced greater barriers and longer delays than men.
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Ultrasound-Enhanced Protective Effect of Tetramethylpyrazine against Cerebral Ischemia/Reperfusion Injury.
PLoS ONE
PUBLISHED: 01-01-2014
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In traditional Chinese medicine, Ligusticum wallichii (Chuan Xiong) and its bioactive ingredient, tetramethylpyrazine (TMP), have been used to treat cardiovascular diseases and to relieve various neurological symptoms, such as those associated with ischemic injury. In the present study, we investigated whether ultrasound (US) exposure could enhance the protective effect of TMP against cerebral ischemia/reperfusion (I/R) injury. Glutamate-induced toxicity to pheochromocytoma (PC12) cells was used to model I/R injury. TMP was paired with US to examine whether this combination could alleviate glutamate-induced cytotoxicity. The administration of TMP effectively protected cells against glutamate-induced apoptosis, which could be further enhanced by US-mediated sonoporation. The anti-apoptotic effect of TMP was associated with the inhibition of oxidative stress and a change in the levels of apoptosis-related proteins, Bcl-2 and Bax. Furthermore, TMP reduced the expression of proinflammatory cytokines such as TNF-? and IL-8, which likely also contributes to its cytoprotective effects. Taken together, our findings suggest that ultrasound-enhanced TMP treatment might be a promising therapeutic strategy for ischemic stroke. Further study is required to optimize ultrasound treatment parameters.
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Genetic reporter analysis reveals an expandable reservoir of OCT4+ cells in adult skin.
Cell Regen (Lond)
PUBLISHED: 01-01-2014
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The transcription factor Oct4 (Pou5f1) is a critical regulator of pluripotency in embryonic and induced pluripotent stem cells. Therefore, Oct4 expression might identify somatic stem cell populations with inherent multipotent potential or a propensity for facilitated reprogramming. However, analysis of Oct4 expression is confounded by Oct4 pseudogenes or non-pluripotency-related isoforms. Systematic analysis of a transgenic Oct4-EGFP reporter mouse identified testis and skin as two principle sources of Oct4 (+) cells in postnatal mice. While the prevalence of GFP(+) cells in testis rapidly declined with age, the skin-resident GFP(+) population expanded in a cyclical fashion. These cells were identified as epidermal stem cells dwelling in the stem cell niche of the hair follicle, which endogenously expressed all principle reprogramming factors at low levels. Interestingly, skin wounding or non-traumatic hair removal robustly expanded the GFP(+) epidermal cell pool not only locally, but also in uninjured skin areas, demonstrating the existence of a systemic response. Thus, the epithelial stem cell niche of the hair follicle harbors an expandable pool of Oct4+ stem cells, which might be useful for therapeutic cell transfer or facilitated reprogramming.
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What is Visualize?

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

How does it work?

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

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

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