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Find video protocols related to scientific articles indexed in Pubmed.
Coffee, tea, and melanoma risk among postmenopausal women.
Eur. J. Cancer Prev.
PUBLISHED: 10-18-2014
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Laboratory research suggests that components in coffee and tea may have anticarcinogenic effects. Some epidemiologic studies have reported that women who consume coffee and tea have a lower risk for melanoma. We assessed coffee, tea, and melanoma risk prospectively in the Women's Health Initiative - Observational Study cohort of 66?484 postmenopausal women, followed for an average of 7.7 years. Coffee and tea intakes were measured through self-administered questionnaires at baseline and at year 3 of follow-up. Self-reported incident melanomas were adjudicated using medical records. Cox proportional hazard models were used to estimate risk, adjusting for covariates, with person-time accumulation until melanoma diagnosis (n=398), death, loss to follow-up, or through 2005. Daily coffee [hazard ratio (HR)=0.87, 95% confidence interval (CI) 0.68-1.12] and tea (HR=1.03, 95% CI 0.81-1.31) intakes were not significantly associated with melanoma risk compared with nondaily intake of each beverage. No significant trends were observed between melanoma risk and increasing intakes of coffee (P for trend=0.38) or tea (P for trend=0.22). Women who reported daily coffee intake at both baseline and year 3 had a significantly decreased risk compared with women who reported nondaily intake at both time points (HR=0.68, 95% CI 0.48-0.97). Consistent daily tea intake was not associated with decreased melanoma risk. Overall, there is no strong evidence that increasing coffee or tea consumption can lead to a lower melanoma risk. We observed a decrease in melanoma risk among long-term coffee drinkers, but the lack of consistency in the results by dose and type cautioned against overinterpretation of the results.
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Nanocomposites of Graphene and Cytochrome P450 2D6 Isozyme for Electrochemical-Driven Tramadol Metabolism.
Langmuir
PUBLISHED: 09-26-2014
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Cytochrome P450 enzymes (cyt P450s) with an active center of iron protoheme are involved in most clinical drugs metabolism process. Herein, an electrochemical platform for the investigation of drug metabolism in vitro was constructed by immobilizing cytochrome P450 2D6 (CYP2D6) with cyt P450 reductase (CPR) on graphene modified glass carbon electrode. Direct and reversible electron transfer of the immobilized CYP2D6 with the direct electron transfer constant of 0.47 s(-1) and midpoint potential of -0.483 V was obtained. In the presence of substrate tramadol, the electrochemical-driven CYP2D6 mediated catalytic behavior toward the conversion of tramadol to o-demethyl-tramadol was confirmed. The Michaelis-Menten constant (Km(app)) and heterogeneous reaction rate constant during the metabolism of tramadol were calculated to be 23.85 ?M and 1.96 cm s(-1), respectively. The inhibition effect of quinidine on CYP2D6 catalyze-cycle was also investigated. Furthermore, this system was applied to studying the metabolism of other drugs.
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Enantioselective aza-Morita-Baylis-Hillman reaction between acrylates and N-Boc isatin ketimines: asymmetric construction of chiral 3-substituted-3-aminooxindoles.
Org. Biomol. Chem.
PUBLISHED: 09-04-2014
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The first enantioselective aza-Morita–Baylis–Hillman reaction of acrylates with ketimines derived from isatins has been developed. With 2 mol% of chiral bifunctional phosphine-squaramide 4e, optically active 3-substituted-3-amino-2-oxindoles were obtained in excellent yields with up to 91% ee.
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Highly sensitive impedimetric aptasensor based on covalent binding of gold nanoparticles on reduced graphene oxide with good dispersity and high density.
Analyst
PUBLISHED: 08-29-2014
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A series of gold nanoparticles (AuNPs) that were covalently bound to 2-aminothiophenol-functionalized reduced graphene oxide (Au-ATP-rGO) composites have been synthesized with well-dispersed and controllable surface coverage of AuNPs. Aptamer immobilization capacity studies demonstrated that the surface density of AuNPs played a key role in increasing the amount of anchoring aptamers to enhance the sensitivity of affinity based detection. With the composites possessing dense surface coverage of AuNPs as a versatile signal amplified platform, a label-free aptasensor for the sensitive and selective detection of small molecules (ochratoxin A in this case) has been developed using electrochemical impedance spectroscopy (EIS). A wide linear range of 0.1-200 ng mL(-1) was obtained with a low detection limit of 0.03 ng mL(-1) (S/N = 3). This work provides a universal strategy for the sensitive detection of a variety of targets in a truly label-free manner by means of changing the corresponding aptamer. The promising platform based on the combination of Au-ATP-rGO composites, EIS technique, and aptamers would have great potential applications in clinical diagnosis, environmental analysis, and food safety monitoring.
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Therapeutic Effects of Fucoidan in 6-Hydroxydopamine-Lesioned Rat Model of Parkinson's disease: Role of NADPH oxidase-1.
CNS Neurosci Ther
PUBLISHED: 08-24-2014
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To explore the effect of fucoidan treatment on oxidative stress-mediated dopaminergic neuronal damage and its potential mechanisms.
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Inclusion of endogenous hormone levels in risk prediction models of postmenopausal breast cancer.
J. Clin. Oncol.
PUBLISHED: 08-18-2014
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Endogenous hormones are risk factors for postmenopausal breast cancer, and their measurement may improve our ability to identify high-risk women. Therefore, we evaluated whether inclusion of plasma estradiol, estrone, estrone sulfate, testosterone, dehydroepiandrosterone sulfate, prolactin, and sex hormone-binding globulin (SHBG) improved risk prediction for postmenopausal invasive breast cancer (n = 437 patient cases and n = 775 controls not using postmenopausal hormones) in the Nurses' Health Study.
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[Nitrogen and phosphate pollution characteristics and eutrophication evaluation for typical urban landscape waters in Hefei City].
Huan Jing Ke Xue
PUBLISHED: 07-25-2014
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To understand the water environment regimes of the city-circling water system in Hefei City, six typical landscape waters were chosen to investigate pollution characteristics of nitrogen and phosphate and evaluate water eutrophication level according to the monitoring data of water physicochemical characteristics and chlorophyll content from September 2012 to July 2013. Study results showed that (1) the six waters mentioned above have been seriously polluted by nitrogen and phosphorus loadings, with the monthly mean values of total nitrogen (TN) and total phosphorus (TP) concentrations far exceeding the universally accepted threshold values of water eutrophication; (2) the nitrogen contents in the waters of Nanfeihe River, Heichiba and Yuhuatang scenic spots exhibited a markedly monthly variation, and both TP and PO(3-)(4)-P in Nanfeihe River showed a fluctuated characteristic with high concentrations while presenting a significant upward trend in Yuhuatang scenic spot; (3) the average values of TN/TP ratios for Yuhuatang and Heichiba scenic spots were 104.7 and 158.3, respectively, and the ratios for Baohe Park, Yinhe Park, Xiaoyaojin Park, and city segment of Nanfeihe River were 16.8, 18.7, 6.4 and 16.8, respectively, indicating that the scenic waters of Yuhuatang and Heichiba were phosphate-limited whereas Xiaoyaojin Park was nitrogen-limited; (4) all the six scenic waters were, in general, subsumed under just two broad categories, namely Hechiba scenic spot and Nanfeihe River, which were seriously polluted, and clustered together, and the others fall into the second class; and (5) water eutrophication appraisal result indicated that the six waters were all in the state of eutrophication, and could be arranged in the order of eutrophication level, Yinhe Park > Heichiba scenic spot > city segment of Nanfeihe River > Xiaoyaojin Park > Yuhuatang scenic spot > Baohe Park.
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Effectiveness of Selected Fitness Exercises on Stress of Femoral Neck using Musculoskeletal Dynamics Simulations and Finite Element Model.
J Hum Kinet
PUBLISHED: 07-08-2014
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The purpose of the study was to establish a dynamics model and a three-dimensional (3D) finite element model to analyze loading characteristics of femoral neck during walking, squat, single-leg standing, and forward and lateral lunges. One male volunteer performed three trials of the five movements. The 3D kinematic data were captured and imported into the LifeMOD to establish a musculoskeletal dynamics model to obtain joint reaction and muscle forces of iliacus, gluteus medius, gluteus maximus, psoas major and adductor magnus. The loading data LfeMOD were imported and transformed into a hip finite-element model. The results of the finite element femur model showed that stress was localized along the compression arc and the tension arc. In addition, the trabecular bone and tension lines of the Ward's triangle also demonstrated high stress. The compact bone received the greatest peak stress in the forward lunge and the least stress in the squat. However, the spongy bone in the femoral neck region had the greatest stress during the walk and the least stress in the squat. The results from this study indicate that the forward lunge may be an effective method to prevent femoral neck fractures. Walking is another effective and simple method that may improve bone mass of the Ward's triangle and prevent osteoporosis and femoral neck fracture.
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Validation of a Brief Opioid Compliance Checklist for Patients With Chronic Pain.
J Pain
PUBLISHED: 05-19-2014
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There has been a need for a brief assessment tool to determine compliance with use of prescribed opioids for pain. The purpose of this study was to develop and begin the validation of a brief and simple compliance checklist (Opioid Compliance Checklist [OCC]) for chronic pain patients prescribed long-term opioid therapy. A review of the literature of opioid therapy agreements led to a 12-item OCC that was repeatedly administered to 157 patients who were taking opioids for chronic pain and followed for 6 months. Validation of the OCC was conducted by identifying those patients exhibiting aberrant drug-related behavior as determined by any of the following: positive urine toxicology screen, a positive score on the Prescription Drug Use Questionnaire interview or Current Opioid Misuse Measure, and/or ratings by staff on the Addiction Behavior Checklist. Of the original 12 items, 5 OCC items appeared to best predict subsequent aberrant behaviors based on multivariate logistic regression analyses (cross-validated area under the receiver operating characteristic curve = .67). Although further testing is needed, these results suggest that the OCC is an easy-to-use, promising measure in monitoring opioid adherence among persons with chronic pain.
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Cytochrome P450 enzyme functionalized-quantum dots as photocatalysts for drug metabolism.
Chem. Commun. (Camb.)
PUBLISHED: 05-14-2014
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On the basis of the photo-induced electron transfer (PET) from CdTe quantum dots (QDs) to cytochrome P450 2C9 (CYP2C9), a light-controlled drug metabolism system was successfully designed by using CYP2C9 functionalized-CdTe QDs as photocatalysts.
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Graphene quantum dots enhanced electrochemiluminescence of cadmium sulfide nanocrystals for ultrasensitive determination of pentachlorophenol.
Analyst
PUBLISHED: 04-18-2014
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An ultrasensitive electrochemiluminescence (ECL) sensor based on the ECL amplifying behavior of the graphene quantum dots-CdS nanocrystals (GQDs-CdS NCs) was constructed for the detection of pentachlorophenol (PCP). Because of the presence of doped GQDs, the resulting GQDs-CdS NCs exhibited 5-fold enhanced ECL intensity than pure CdS NCs with the ECL onset potential positively shifted by 80 mV. Furthermore, based on the effective inhibition of the ECL response of GQDs-CdS NCs film by PCP, a simple method for ultrasensitive determination of PCP was devised, which showed a wide linear range of 0.01-500 ng mL(-1) and a low detection limit of 3 pg mL(-1) (S/N = 3) with good stability, reproducibility and applicability for PCP detection in real water samples. Thus, it can be expected that GQDs-based composites with excellent performance may play a more important role in pesticide determination.
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Assumptions regarding right censoring in the presence of left truncation.
Stat Probab Lett
PUBLISHED: 04-01-2014
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Clinical studies using complex sampling often involve both truncation and censoring, where there are options for the assumptions of independence of censoring and event and for the relationship between censoring and truncation. In this paper, we clarify these choices, show certain equivalences, and provide examples.
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Samarium and yttrium codoped BaCeO? proton conductor with improved sinterability and higher electrical conductivity.
ACS Appl Mater Interfaces
PUBLISHED: 03-28-2014
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Acceptor-doped barium cerate is considered as one of the state-of-the-art high temperature proton conductors (HTPCs), and the proton conductivity of such HTPCs is heavily dependent on the dopant. In this work, a codoping strategy is employed to improve the electrical conductivity and sinterability of BaCeO3-based HTPC. BaCe0.8Sm(x)Y(0.2-x)O(3-?) (0 ? x ? 0.2) powders are synthesized by a typical citrate-nitrate combustion method. The XRD and Raman spectra reveal all the compounds have an orthorhombic perovskite structure. The effects of Sm and/or Y doping on the sinterability and electrical conductivity under different atmospheres are carefully investigated. The SEM results of the sintered BaCe0.8Sm(x)Y(0.2-x)O(3-?) pellets indicate a significant sintering enhancement with increasing Sm concentration. BaCe0.8Sm0.1Y0.1O(3-?) exhibits the highest electrical conductivity in hydrogen among the BaCe0.8Sm(x)Y(0.2-x)O(3-?) pellets. Anode-supported BaCe0.8Sm0.1Y0.1O(3-?) electrolyte membranes are also fabricated via a drop-coating process, and the corresponding single cell exhibits desirable power performance and durability at low temperatures. The results demonstrate that BaCe0.8Sm0.1Y0.1O(3-?) is a promising proton conductor with high conductivity and sufficient sinterability for proton-conducting solid oxide fuel cells operating at reduced temperatures.
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Differential requirements of arrestin-3 and clathrin for ligand-dependent and -independent internalization of human G protein-coupled receptor 40.
Cell. Signal.
PUBLISHED: 03-22-2014
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G protein-coupled receptor 40 (GPR40) is believed to be an attractive target to enhance insulin secretion in patients with type 2 diabetes. GPR40 has been found to couple to Gq protein, leading to the activation of phospholipase C and subsequent increases in the intracellular Ca(2+) level. However, the underlying mechanisms that regulate the internalization and desensitization of GPR40 remain to be elucidated. In the present study, a construct of GPR40 fused with enhanced green fluorescent protein (EGFP) at its C-terminus was constructed for direct imaging of the localization and internalization of GPR40 by confocal microscopy. In stably transfected HEK-293 cells, GPR40 receptors underwent rapid agonist-induced internalization and constitutive ligand-independent internalization. Our data demonstrated that the agonist-mediated internalization of GPR40 was significantly blocked by hypertonic sucrose treatment and by siRNA mediated depletion of the heavy chain of clathrin. In contrast, constitutive GPR40 internalization was not affected by hypertonic sucrose or by knock-down of clathrin expression, but it was affected by treatment with methyl-?-cyclodextrin (M?CD) and nystatin. Furthermore, our results using an arrestin-3-EGFP redistribution assay and siRNA-mediated knock-down of arrestin-3 and GRK2 expression revealed that arrestin-3 and GRK2 play an essential role in the regulation of agonist-mediated GPR40 internalization, but are not involved in the regulation of constitutive GPR40 internalization. Additionally, our observation showed that upon activation by agonist, the internalized GPR40 receptors were rapidly recycled back to the plasma membrane via Rab4/Rab5 positive endosomes, whereas the constitutively internalized GPR40 receptors were recycled back to the cell surface through Rab5 positive endosomes. Because FFA receptors exhibit a high level of homology, our observations could be applicable to other members of this family.
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The US healthcare workforce and the labor market effect on healthcare spending and health outcomes.
Int J Health Care Finance Econ
PUBLISHED: 02-27-2014
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The healthcare sector was one of the few sectors of the US economy that created new positions in spite of the recent economic downturn. Economic contractions are associated with worsening morbidity and mortality, declining private health insurance coverage, and budgetary pressure on public health programs. This study examines the causes of healthcare employment growth and workforce composition in the US and evaluates the labor market's impact on healthcare spending and health outcomes. Data are collected for 50 states and the District of Columbia from 1999-2009. Labor market and healthcare workforce data are obtained from the Bureau of Labor Statistics. Mortality and health status data are collected from the Centers for Disease Control and Prevention's Vital Statistics program and Behavioral Risk Factor Surveillance System. Healthcare spending data are derived from the Centers for Medicare and Medicaid Services. Dynamic panel data regression models, with instrumental variables, are used to examine the effect of the labor market on healthcare spending, morbidity, and mortality. Regression analysis is also performed to model the effects of healthcare spending on the healthcare workforce composition. All statistical tests are based on a two-sided [Formula: see text] significance of [Formula: see text] .05. Analyses are performed with STATA and SAS. The labor force participation rate shows a more robust effect on healthcare spending, morbidity, and mortality than the unemployment rate. Study results also show that declining labor force participation negatively impacts overall health status ([Formula: see text] .01), and mortality for males ([Formula: see text] .05) and females ([Formula: see text] .001), aged 16-64. Further, the Medicaid and Medicare spending share increases as labor force participation declines ([Formula: see text] .001); whereas, the private healthcare spending share decreases ([Formula: see text] .001). Public and private healthcare spending also has a differing effect on healthcare occupational employment per 100,000 people. Private healthcare spending positively impacts primary care physician employment ([Formula: see text] .001); whereas, Medicare spending drives up employment of physician assistants, registered nurses, and personal care attendants ([Formula: see text] .001). Medicaid and Medicare spending has a negative effect on surgeon employment ([Formula: see text] .05); the effect of private healthcare spending is positive but not statistically significant. Labor force participation, as opposed to unemployment, is a better proxy for measuring the effect of the economic environment on healthcare spending and health outcomes. Further, during economic contractions, Medicaid and Medicare's share of overall healthcare spending increases with meaningful effects on the configuration of state healthcare workforces and subsequently, provision of care for populations at-risk for worsening morbidity and mortality.
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Effects of partial deletion of the wzm and wzt genes on lipopolysaccharide synthesis and virulence of Brucella abortus S19.
Mol Med Rep
PUBLISHED: 02-21-2014
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Brucellosis is a worldwide human and animal infectious disease, and the effective methods of its control are immunisation of animals by vaccination and elimination. Brucella abortus S19 is one of the popular vaccines with virulence in the control of cattle Brucellosis. In the present study, allelic exchange plasmids of wzm and wzt genes and partial knockout mutants of wzm and wzt were constructed to evaluate the resulting difference in virulence of B. abortus S19. PCR analysis revealed that the target genes were knocked out. The mutants were rough mutants and they could be differentiated from natural infection by the Rose Bengal plate and standard agglutination tests. The molecular weights of lipopolysaccharides of the ?wzm and ?wzt mutants were clustered between 25 and 40 kDa, and 30 and 35 kDa separately, and were markedly different from those in B. abortus S19. The virulence of B. abortus ?wzm and ?wzt was decreased compared with that of B. abortus S19 in mice. All these results identified that there were several differences between the wzm and wzt genes on lipopolysaccharide synthesis and on the virulence of B. abortus.
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Autophagy inhibition sensitizes bladder cancer cells to the photodynamic effects of the novel photosensitizer chlorophyllin e4.
J. Photochem. Photobiol. B, Biol.
PUBLISHED: 02-12-2014
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We previously developed a novel photosensitizer, chlorophyllin e4, and found that chlorophyllin e4 mediated-PDT could kill 5637 and T24 cells by inducing apoptotic cell death. Here, we further investigated the new mechanism of autophagy and determined its relevance to apoptosis in e4-PDT. We demonstrated that chlorophyllin e4 was located in both lysosome and mitochondria, and autophagy also occurred in bladder cancer cells upon e4-PDT. More importantly, autophagy played a pro-survival role, and its inhibition enhanced e4-PDT-associated apoptotic cell death because cells pretreated with the typical autophagy inhibitor either 3-methyladenine or Bafilomycin A1 exhibited much lower cell viability and higher apoptotic cell death. Thus, these data imply that the combination of PDT, when mediated by our new photosensitizer chlorophyllin e4, and an autophagy inhibitor might be a promising approach to the eliminationof non-muscle invasive bladder cancer.
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High expression and prognostic role of CAP1 and CtBP2 in breast carcinoma: associated with E-cadherin and cell proliferation.
Med. Oncol.
PUBLISHED: 01-29-2014
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Overexpression of C-terminal binding protein-2 (CtBP2) has been noted to correlate with cancer metastasis in several human cancers including breast cancer. The aim of this study was to examine the effect of cyclase-associated protein 1 (CAP1) overexpression on CtBP2 expression and related mechanism in the metastasis of breast cancer. Immunohistochemical analysis was performed in 100 human breast carcinoma samples, and the data were correlated with clinicopathologic features. Furthermore, Western blot analysis was performed for CAP1 and CtBP2 in breast carcinoma samples and cell lines to evaluate their protein levels and molecular interaction. We found that the expression of CAP1 was positively related to CtBP2 expression (P<0.01); moreover, CAP1 expression was significantly correlated with histologic grade (P<0.01) and negatively related to E-cadherin expression (P<0.01). Meanwhile, CtBP2 expression obtained similar results. Kaplan-Meier survival analysis showed that overexpression of CAP1 and CtBP2 exhibited a significant correlation with poor prognosis in human breast cancer (P<0.01). While in vitro, we employed siRNA technique to knockdown CAP1 and CtBP2 expressions and observed their effects on MDA-MB-231 cells growth. CtBP2 depletion by siRNA-inhibited cell proliferation, resulted in increased E-cadherin levels. Moreover, knockdown of CAP1 resulted in decreased CtBP2 and increased E-cadherin expression. On the basis of these results, we suggested that CAP1's oncogenic abilities appear to be triggered at least in part by the modulation of CtBP2 and E-cadherin, which might serve as a future target for breast cancer.
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Polyoxometalate@magnetic graphene as versatile immobilization matrix of Ru(bpy)3(2+) for sensitive magneto-controlled electrochemiluminescence sensor and its application in biosensing.
Biosens Bioelectron
PUBLISHED: 01-28-2014
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We demonstrated here the exploration of polyoxometalate (POM) coated magnetic Fe3O4/reduced graphene oxide (POM@mrGO) composite as the versatile immobilization matrix for the electrochemiluminescence (ECL) agent Ru(bpy)3(2+). The effective modification of Ru(bpy)3(2+)/POM@mrGO hybrid simply involved using magnetic electrode showed 10-fold ECL intensity increase than that observed for Ru(bpy)3(2+)/Nafion@mrGO to the same concentration of nicotinamide adenine dinucleotide (NADH), which is largely due to POM?s good electrocatalytic activity towards NADH oxidation. These findings allowed the stable and ultrasensitive ECL detection of NADH as low as 0.1 nM. The good stability and high sensitivity of the magneto-controlled ECL sensor enabled us to explore the feasibility of applying the sensing platform to fabricating the ECL biosensors in which the NADH was produced from the dehydrogenase-based enzymatic reaction in the presence of NAD(+) cofactor. With L-lactate dehydrogenase as a model, a L-lactate biosensor was successfully constructed where we showed that the ECL intensity of the biosensor increased with the increasing L-lactate concentration. Excellent performance of the presented biosensor has been achieved including a wide linear range extended from 5.0×10(-9) M to 5.0×10(-4) M and an extremely low detection limit of 0.4 nM. Such sensing strategy combines enzymatic selectivity with simple sensor preparation can be used as a new and biocompatible platform for dehydrogenase-based ECL biosensing.
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?-Fe2O3 cubes with high visible-light-activated photoelectrochemical activity towards glucose: hydrothermal synthesis assisted by a hydrophobic ionic liquid.
Chemistry
PUBLISHED: 01-23-2014
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A liquid/liquid interfacial reaction system was designed to fabricate ?-Fe2O3 cubes. The reaction system uses a hydrophobic ionic liquid containing iron ions ([(C8H17)2(CH3)2N]FeCl4) for manufacturing ?-Fe2O3 cubes by a novel and environmentally friendly hydrothermal method under low-temperature conditions (140?°C). The iron-containing ionic liquid is hydrophobic and can form a liquid/liquid interface with water, which is vital for fabrication of the ?-Fe2O3 cubes. Nanomaterials synthesized from hydrophobic iron-containing ionic liquids show good crystallinity, well-developed morphology, and uniform size. The effect of different ionic liquids on the morphology of ?-Fe2 O3 was investigated in detail. [(C8H17)2(CH3)2N]FeCl4 is assumed to perform the triple role of forming a liquid/liquid interface with water and acting as reactant and template at the same time. The effect of the reaction temperature on the formation of the ?-Fe2O3 cubes was also studied. Temperatures lower or higher than 140?°C are not conducive to formation of the ?-Fe2O3 cubes. Their photoelectrochemical properties were tested by means of the transient photocurrent response of electrodes modified with as-prepared ?-Fe2O3 cubes. The photocurrent response of an ?-Fe2O3 cubes/indium tin oxide electrode is high and stable, and it shows great promise as a photoelectrochemical glucose sensor with high sensitivity and fast response, which are beneficial to practical applications of nanosensors.
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Mild to moderate Alzheimer dementia with insufficient neuropathological changes.
Ann. Neurol.
PUBLISHED: 01-22-2014
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Recently, ~16% of participants in an anti-A? passive immunotherapy trial for mild-to-moderate Alzheimer disease (AD) had a negative baseline amyloid positron emission tomography (PET) scan. Whether they have AD or are AD clinical phenocopies remains unknown. We examined the 2005-2013 National Alzheimer's Coordinating Center autopsy database and found that ~14% of autopsied subjects clinically diagnosed with mild-to-moderate probable AD have no or sparse neuritic plaques, which would expectedly yield a negative amyloid PET scan. More than half of these "A?-negative" subjects have low neurofibrillary tangle Braak stages. These findings support the implementation of a positive amyloid biomarker as an inclusion criterion in future anti-A? drug trials.
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Fabrication of magnetically separable fluorescent terbium-based MOF nanospheres for highly selective trace-level detection of TNT.
Dalton Trans
PUBLISHED: 01-22-2014
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In this work, we present novel kinds of Fe3O4@Tb-BTC magnetic metal-organic framework (MOF) nanospheres which possess both magnetic characteristics and fluorescent properties using a layer by layer assembly technique. The structure and morphology of the as-prepared Fe3O4@Tb-BTC were systematically characterized and it was applied in detection of nitroaromatic explosives, such as 2,4-dinitrotoluene (2,4-DNT), 2,6-dinitrotoluene (2,6-DNT), 2-nitrotoluene (2-NT), 4-nitrotoluene (4-NT), nitrobenzene (NB) and picric acid (PA). The results indicate that the fluorescence intensity of Fe3O4@Tb-BTC can be quenched by all analytes studied in the present work. Remarkably, the as-synthesized nanospheres exhibit high sensitivity for 2,4,6-trinitrotoluene (TNT) detection with Ksv value of (94?800 M(-1)). Besides, the magnetic nanospheres can be easily recycled, which makes it more convenient for reutilization and friendly to the environment. The results show that it has broad application prospects in the detection of nitroaromatic explosives.
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Pre-adjuvant chemotherapy leukocyte count may predict the outcome for advanced gastric cancer after radical resection.
Biomed. Pharmacother.
PUBLISHED: 01-20-2014
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Gastric cancer (GC) has a high morbidity worldwide each year especially in China and advanced GC is well known with poor prognosis, for which surgical resection combine adjuvant chemotherapy is the optimal choice for therapy. Leukocyte is an important index during the treatment for its influence on drugs' dosage and tolerance. Therefore, peripheral blood leukocyte and its subsets during adjuvant chemotherapy may have great clinical value for predicting prognostic. In this retrospective study, we showed the distribution of white blood cell and its subsets in the baseline period before adjuvant chemotherapy in 399 patients who underwent radical resection for advanced GC from January 1, 2008 to August 31, 2012. We investigated the relationship between leukocyte count and overall survival (OS) as well as disease-free survival (DFS). In these patients, females were more likely to have less white blood cells after operation (P=0.016). Patients with pre-chemotherapy leukocyte count less than 4×10(9)/L got worse DFS (P=0.028) and OS (P=0.016). In multivariate analysis, tumor size ? 6cm (P=0.033), TNM stage IV (P=0.024), vascular or nerval invasion (P=0.005) and leukocyte count less than 4.0×10(9)/L (P=0.019) was associated with poor DFS. TNM stage IV (P=0.008), vascular or nerval invasion (P=0.001) and lower leukocyte count (P=0.045) were independent risk factors for poor OS. Taken together, our findings suggest that pre-adjuvant chemotherapy peripheral blood leukocyte count correlates with clinical outcome of patients with advanced GC after radical resection.
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Involvement of ?-arrestin-2 and Clathrin in Agonist-Mediated Internalization of the Human Cannabinoid CB2 Receptor.
Curr Mol Pharmacol
PUBLISHED: 01-14-2014
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The CB2 cannabinoid receptor is a promising therapeutic target for the treatment of inflammatory diseases, neuropathic pain, liver diseases, cancer and cardiovascular diseases. Obtaining detailed information on the internalization and trafficking of the human CB2 receptor in response to agonist will have a significant impact on drug discovery. Visualization and quantitative detection of EGFP-tagged CB2 receptor showed that, upon WIN55,212-2 stimulation, the CB2 receptor was rapidly internalized in a dose- and time-dependent manner from the cell membrane into the cytoplasm. Pretreatment with hypertonic sucrose, MDC clathrin inhibitor, or siRNA-mediated knock-down of clathrin heavy chain led to significant inhibition of agonist-induced CB2 internalization. Using the RNA interference method, we showed that knockdown of ?-arrestin2 expression significantly impaired receptor internalisation. Further investigation demonstrated that the internalized CB2 receptors were co-localized with the early endosome probe and were recycled to the cell surface after the removal of agonist, but treatment with specific cell-permeable proteasome inhibitor MG132 a inhibited the recycling of internalized CB2 receptor, suggesting that the proteasome-mediated degradation pathway may be involved in CB2 internalization. Moreover, the single residue Ser352 and residue cluster S335S336T338T340 at the C-terminal tail are shown to be essential for receptor phosphorylation and ?-arrestin2 association. These data provide new insights into the mechanisms regulating agonist-mediated internalization and trafficking of the human CB2 receptor.
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How hepatitis C virus invades hepatocytes: the mystery of viral entry.
World J. Gastroenterol.
PUBLISHED: 01-03-2014
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Hepatitis C virus (HCV) infection is a global health problem, with an estimated 170 million people being chronically infected. HCV cell entry is a complex multi-step process, involving several cellular factors that trigger virus uptake into the hepatocytes. The high- density lipoprotein receptor scavenger receptor class B type I, tetraspanin CD81, tight junction protein claudin-1, and occludin are the main receptors that mediate the initial step of HCV infection. In addition, the virus uses cell receptor tyrosine kinases as entry regulators, such as epidermal growth factor receptor and ephrin receptor A2. This review summarizes the current understanding about how cell surface molecules are involved in HCV attachment, internalization, and membrane fusion, and how host cell kinases regulate virus entry. The advances of the potential antiviral agents targeting this process are introduced.
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Photodynamic therapy with the novel photosensitizer chlorophyllin f induces apoptosis and autophagy in human bladder cancer cells.
Lasers Surg Med
PUBLISHED: 01-02-2014
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Our group recently synthesized a new, low-cost photosensitizer, chlorophyllin f. In this study, the effects of chlorophyllin f-mediated photodynamic therapy (PDT) and its potential mechanisms were examined in human bladder cancer cells.
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Audits of the quality of perioperative antibiotic prophylaxis in Shandong Province, China, 2006 to 2011.
Am J Infect Control
PUBLISHED: 01-01-2014
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A prospective multicenter survey was conducted to assess the rational use of antibiotics in clean and clean-contaminated elective surgical procedures applied in 53 grade III first class hospitals in Shandong Province, China, from 2006 to 2011. The survey was designed to examine the prevalence of antibiotic prophylaxis, evaluate the quality of perioperative antibiotic prophylaxis (PAP) prescriptions, and investigate the risk factors associated with inappropriate indication for antibiotic prophylaxis.
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Diagnostic performance of lung ultrasound in the diagnosis of pneumonia: a bivariate meta-analysis.
Int J Clin Exp Med
PUBLISHED: 01-01-2014
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Pneumonia is a common disease with both high morbidity and mortality, the diagnosis of pneumonia remains a clinical challenge. Many studies have been conducted to identify the usefulness of lung ultrasound for the diagnosis of pneumonia, but with inconsistent and inconclusive results. The present study aimed to establish the overall diagnostic accuracy of lung ultrasound in diagnosing pneumonia.
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Diagnostic accuracy of interferon gamma-induced protein 10 for tuberculosis: a meta-analysis.
Int J Clin Exp Med
PUBLISHED: 01-01-2014
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The diagnostic accuracy of tuberculosis (TB) remains a clinical challenge, and a number of studies have used the interferon gamma-induced protein 10 (IP-10) in the diagnosis of TB. The aim of the present meta-analysis was to determine the overall accuracy of IP-10 in the diagnosis of TB. A systematic review of studies published in English from Medline, Embase and Cochrane Library was conducted and the data concerning the accuracy of IP-10 in the diagnosis of TB were pooled. The methodological quality of each study was assessed by QUADAS (quality assessment for studies of diagnostic accuracy). Statistical analysis was performed by employing Meta-Disc 1.4 soft-ware and STATA. The overall test performance was summarized using receiver operating characteristic curves. 14 studies, based on 2075 subjects, met the inclusion criteria. The summary estimates for IP-10 in the diagnosis of TB were: sensitivity 0.73 (95% CI, 0.71-0.76), specificity 0.83 (95% CI, 0.81-0.86), positive likelihood ratio 7.08 (95% CI, 3.94-12.72), negative likelihood ratio 0.26 (95% CI, 0.20-0.35) and diagnostic odds ratio 29.50 (95% CI, 14.43-60.30), and the area under the curve was 0.88. Our findings suggest that IP-10 may improve the accuracy of TB diagnosis, while the results of IP-10 assays should be interpreted in parallel with conventional test results and other clinical findings.
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Anti-HIV-1 activities of extracts and phenolics from Smilax china L.
Pak J Pharm Sci
PUBLISHED: 01-01-2014
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Four extracts (EtOH, CHCl3, EtOAc, and BuOH) and five phenolics (dihydrokaempferol (1), resveratrol (2), kaempferol-7-O-?-D-glucoside (3), dihydrokaempferol-3-O-?-L-rhamnoside (4), oxyresveratrol (5)) from Smilax china L. was evaluated for anti-HIV-1 activities and cytotoxicity activities in vitro. All these extracts and phenolics showed lower or no cytotoxicity at a concentration ranged from 0.8 ?g/mL to 100 ?g/mL, but some showed potential anti-HIV-1 activities, that is, BuOH extract and compound 2 showed higher anti-HIV-1 activities than other extracts and compounds in the tested concentrations. EtOAc extract and compound 1 and 3 showed moderate anti-HIV-1 activities at a concentration higher than 4 ?g/mL. In the end, the structure-activity relationship of four extracts and five phenolics was discussed.
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Efficient single-strand cleavage of DNA mediated by a Mn(III)Mn(IV)-based artificial nuclease.
Dalton Trans
PUBLISHED: 12-11-2013
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A water-soluble Mn(IV) 1,4,7-triazacyclononane complex, [Mn(IV)22(?-O)2](ClO4)2·2H2O (), was prepared to serve as a nuclease mimic ( = 1,4,7-triazacyclononane-N-acetate). Complex was readily synthesized from the highly water soluble ligand (), with Mn(III) salt, [Mn3O(MeCO2)7]·3H2O in basic condition, and characterized by X-ray, IR, electronic spectroscopy, cyclic voltammetry and magnetic susceptibility as well as ESI-MS. The bond valence sum (BVS) analysis and magnetic data suggest that is a Mn(IV)-?-O2-Mn(IV) species. The electrospray mass spectrum and electronic spectrum of in aqueous solution indicates that dinuclear Mn complex [Mn(III)Mn(IV)2(?-O)2](+) () is the active species. A predominantly hydrolytic cleavage mechanism was confirmed through experiments performed in the presence of various radical scavengers, T4 ligase and under anaerobic conditions. The kinetic aspects of DNA cleavage under pseudo- or true-Michaelis-Menten conditions were also detailed, kinetic parameters (kcat, KM, Vmax) were calculated to be 6.27 h(-1), 7.35 × 10(-5) M, 4.6 × 10(-4) M h(-1); 0.683 h(-1), 1.93 × 10(-5) M, 1.32 × 10(-5) M h(-1) for , respectively.
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Examination of the clinicopathologic continuum of Alzheimer disease in the autopsy cohort of the national Alzheimer coordinating center.
J. Neuropathol. Exp. Neurol.
PUBLISHED: 11-15-2013
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To test the hypothesis that Alzheimer disease (AD) is a clinical and pathologic continuum between normal aging and end-stage dementia, we selected a convenience sample of subjects from the National Alzheimer Coordinating Center 2005 to 2012 autopsy cohort (n = 2,083) with the last clinical evaluation within 2 years before autopsy and no other primary neuropathologic diagnosis. Demographic and neuropathologic characteristics were correlated with the Clinical Dementia Rating-Sum of Boxes in the 835 subjects meeting these criteria. Both neuritic plaques and neurofibrillary tangles independently predicted Clinical Dementia Rating-Sum of Boxes. Severe small-vessel disease, severe amyloid angiopathy, and hippocampal sclerosis were also independently associated with the degree of cognitive impairment. By contrast, education was a strong independent protective factor against cognitive deficits. The cause of mild to moderate dementia remained uncertain in 14% of the patients. Inverse probability weighting suggests the generalizability of these results to nonautopsied cohorts. These data indicate that plaques and tangles independently contribute to cognitive impairment, that concurrent vascular disease strongly correlates with cognitive dysfunction even in a sample selected to represent the AD pathologic continuum, and that education further modifies clinical expression. Thus, multiple concomitant etiologies of brain damage and premorbid characteristics contribute to the uncertainty of AD clinicopathologic correlations based only on tangles and plaques.
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Human miRNome Profiling Identifies MicroRNAs Differentially Present in the Urine after Kidney Injury.
Clin. Chem.
PUBLISHED: 10-23-2013
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Extracellular microRNAs (miRNAs) have been proposed as potentially robust and stable biomarkers of various disease conditions. The primary objective of this study was to identify miRNAs differentially occurring in the urine that could serve as potential biomarkers of acute kidney injury (AKI), because traditional AKI markers have limitations with respect to sensitivity, specificity, and timeliness of diagnosis.
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Enhanced peroxydisulfate electrochemiluminescence for dopamine biosensing based on Au nanoparticle decorated reduced graphene oxide.
Analyst
PUBLISHED: 10-09-2013
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This work reports a novel strategy to amplify the electrochemiluminescence (ECL) signal of peroxydisulfate solution based on the Au nanoparticle decorated reduced graphene oxide (Au NP-RGO), and further an ECL biosensor for sensitive and selective detection of dopamine (DA) was constructed. Due to the synergistic amplification of Au NPs and RGO, the ECL signal of peroxydisulfate solution on the Au NP-RGO modified electrode was about 5-fold enhanced compared to that of the bare electrode with the ECL onset potential positively shifted from -1.2 V to -0.9 V. More interestingly, the ECL intensity of peroxydisulfate solution increased with the increase of DA concentration, based on which an ECL biosensor for DA determination was fabricated. The as-prepared solid-state ECL DA sensor showed a wide linear response of 0.02-40 ?M with a detection limit of 6.7 nM (S/N = 3). Moreover, we expect this work would open up a new field in the application of peroxydisulfate solution ECL for highly sensitive bioassays.
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AgX/graphite-like C(3)N(4) (X = Br, I) hybrid materials for photoelectrochemical determination of copper(II) ion.
Analyst
PUBLISHED: 09-19-2013
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A novel photoelectrochemical strategy has been designed for the detection of Cu(2+) with AgX/g-C3N4 (X = Br, I) hybrid materials. The present study can serve as a foundation for the application of AgX/g-C3N4 hybrid materials in photoelectron-chemical ion sensing. It can be successfully applied to the detection of copper in human hair samples.
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[The protective effect of photochromic intraocular lens on visible light-induced lesion in cultured retinal pigment epithelium].
Zhonghua Yan Ke Za Zhi
PUBLISHED: 09-12-2013
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To evaluate the protective effect of photochromic intraocular lens (IOL) on visible light-induced lesion in cultured retinal pigment epithelium (RPE).
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Ultrasensitive electrochemical aptasensor for ochratoxin A based on two-level cascaded signal amplification strategy.
Bioelectrochemistry
PUBLISHED: 09-11-2013
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Ochratoxin A (OTA) has a number of toxic effects to both humans and animals, so developing sensitive detection method is of great importance. Herein, we describe an ultrasensitive electrochemical aptasensor for OTA based on the two-level cascaded signal amplification strategy with methylene blue (MB) as a redox indicator. In this method, capture DNA, aptamers, and reporter DNA functionalized-gold nanoparticles (GNPs) were immobilized on the electrode accordingly, where GNPs were used as the first-level signal enhancer. To receive the more sensitive response, a larger number of guanine (G)-rich DNA was bound to the GNPs surface to provide abundant anchoring sites for MB to achieve the second-level signal amplification. By employing this novel strategy, an ~8.5 (±0.3) fold amplification in signal intensity was obtained. Afterward, OTA was added to force partial GNPs/G-rich DNA to release from the sensing interface and thus decreased the electrochemical response. An effective sensing range from 2.5pM to 2.5nM was received with an extremely low detection limit of 0.75 (±0.12) pM. This amplification strategy has the potential to be the main technology for aptamer-based electrochemical biosensor in a variety of fields.
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WT1 promotes invasion of NSCLC via suppression of CDH1.
J Thorac Oncol
PUBLISHED: 08-16-2013
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The Wilms tumor gene (WT1) has been identified as an oncogene in many malignant diseases, and aberrant WT1 expression has been linked to development, progression, and prognosis of non-small-cell lung cancer (NSCLC). We sought to investigate the underlying mechanism of WT1 and metastasis in NSCLC.
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Enhanced non-enzymatic glucose sensing based on copper nanoparticles decorated nitrogen-doped graphene.
Biosens Bioelectron
PUBLISHED: 08-13-2013
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Copper nanoparticles (NPs) decorated nitrogen-doped graphene (Cu-N-G) was prepared by a facile thermal treatment, and further employed as a novel sensing material for fabricating the sensitive non-enzymatic glucose sensor. Compared with pure Cu NPs, the Cu-N-G showed enhanced electrocatalytic activity to glucose oxidation due to the integration of N-G, which exhibited the oxidation peak current of glucose ca. 23-fold higher than that of pure Cu NPs. The presented sensor showed excellent performances for glucose detection including wide linear range of 0.004-4.5mM, low detection limit (1.3?M, S/N=3), high sensitivity (48.13?AmM(-1)), fast response time (<5s), good selectivity to the general coexisted interferences, etc. Such properties would promote the potential application of the nitrogen-doped graphene as enhanced materials in fabricating sensors for chemical and biochemical analysis.
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Amplified impedimetric aptasensor based on gold nanoparticles covalently bound graphene sheet for the picomolar detection of ochratoxin A.
Anal. Chim. Acta
PUBLISHED: 08-08-2013
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An amplified electrochemical impedimetric aptasensor for ochratoxin A (OTA) was developed with picomolar sensitivity. A facile route to fabricate gold nanoparticles covalently bound reduced graphene oxide (AuNPs-rGO) resulted in a large number of well-dispersed AuNPs on graphene sheets with tremendous binding sites for DNA, since the single rGO sheet and each AuNP can be loaded with hundreds of DNA strands. An aptasensor with sandwich model was fabricated which involved thiolated capture DNA immobilized on a gold electrode to capture the aptamer, then the sensing interface was incubated with OTA at a desired concentration, followed by AuNPs-rGO functionalized reporter DNA hybridized with the residual aptamers. By exploiting the AuNPs-rGO as an excellent signal amplified platform, a single hybridization event between aptamer and reporter DNA was translated into more than 10(7) redox events, leading to a substantial increase in charge-transfer resistance (Rct) by 7? orders of magnitude compared with that of the free aptamer modified electrode. Such designed aptasensor showed a decreased response of Rct to the increase of OTA concentrations over a wide range of 1pgmL(-1)-50ngmL(-1) and could detect extremely low OTA concentration, namely, 0.3pgmL(-1) or 0.74pM, which was much lower than that of most other existed impedimetric aptasensors. The signal amplification platform presented here would provide a promising model for the aptamer-based detection with a direct impedimetric method.
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The 2518 A/G polymorphism in the MCP-1 gene and cancer risk: a meta-analysis.
Asian Pac. J. Cancer Prev.
PUBLISHED: 07-27-2013
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The 2518 A/G polymorphism in the MCP-1 gene has been extensively studied for associations with cancer; however, results from replication studies have been inconsistent. The aim of this investigation was to determine links with risk of cancer by meta-analysis.
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[Abnormal expression of insulin-like growth factor-II and intervening of its mRNA transcription in the promotion of HepG2 cell apoptosis].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 07-19-2013
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To explore the expression and pathological features of insulin-like growth factor-II (IGF-II) in tissues and sera of hepatocellular carcinoma (HCC) patients and the siRNA-mediated inhibition of IGF-II mRNA transcription in human HepG2 cells.
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Diagnostic accuracy of neutrophil CD64 expression in neonatal infection: a meta-analysis.
J. Int. Med. Res.
PUBLISHED: 07-18-2013
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The aim of the present study was to establish the predictive values of neutrophil CD64 expression in diagnosing neonatal infection.
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A 20-year prospective study of plasma prolactin as a risk marker of breast cancer development.
Cancer Res.
PUBLISHED: 06-19-2013
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Understanding how the timing of exposure to endogenous hormones influences cancer development is critical to elucidating disease etiology. Prolactin increases proliferation and cell motility, processes important in later stage tumor development, suggesting that levels proximate (versus distant) to diagnosis may better predict risk. Thus, we calculated relative risks (RR) and 95% confidence intervals (CI) for prolactin levels on samples collected <10 (proximate) versus ?10 (distant) years before diagnosis in the Nurses Health Study (NHS) and NHSII with breast cancer risk, including in a subset of NHS women providing two samples 10 years apart. We measured prolactin via immunoassay in cases diagnosed from 1990 to 2010 (NHS) and 1999 to 2009 (NHSII) and matched controls. Overall, 2,468 cases and 4,021 controls had prolactin measured <10 years and 953 cases and 1,339 controls >10 years before diagnosis/reference date. There was an increased risk for higher proximate prolactin levels [RR, >15.7 vs. ?8.1 ng/mL (i.e., top vs. bottom quartiles) = 1.20; 95% CI, 1.03-1.40; Ptrend = 0.005], but not for distant levels (RR = 0.97; Ptrend = 0.94); results were similar among women with two blood samples (Pinteraction, proximate vs. distant = 0.07). The positive association was stronger for ER(+) disease (RR = 1.28; Ptrend = 0.003) and postmenopausal women (RR = 1.37; Ptrend = 0.0002). Among postmenopausal women, the association was strongest for ER(+) disease (RR = 1.52) and lymph node-positive cases (RR = 1.63). Our data suggest that prolactin levels measured <10 years before diagnosis are most strongly associated with postmenopausal breast cancer risk, especially for ER(+) tumors and metastatic disease. This corresponds with biologic data that prolactin is etiologically important in tumor promotion.
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A clinically relevant androgen receptor mutation confers resistance to second-generation antiandrogens enzalutamide and ARN-509.
Cancer Discov
PUBLISHED: 06-18-2013
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Despite the impressive clinical activity of the second-generation antiandrogens enzalutamide and ARN-509 in patients with prostate cancer, acquired resistance invariably emerges. To identify the molecular mechanisms underlying acquired resistance, we developed and characterized cell lines resistant to ARN-509 and enzalutamide. In a subset of cell lines, ARN-509 and enzalutamide exhibit agonist activity due to a missense mutation (F876L) in the ligand-binding domain of the androgen receptor (AR). AR F876L is sufficient to confer resistance to ARN-509 and enzalutamide in in vitro and in vivo models of castration-resistant prostate cancer (CRPC). Importantly, the AR F876L mutant is detected in plasma DNA from ARN-509-treated patients with progressive CRPC. Thus, selective outgrowth of AR F876L is a clinically relevant mechanism of second-generation antiandrogen resistance that can potentially be targeted with next-generation antiandrogens.
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Meta-analysis on the possible association between in vitro fertilization and cancer risk.
Int. J. Gynecol. Cancer
PUBLISHED: 06-06-2013
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We aimed to examine the association between in vitro fertilization (IVF) and risk of cancers through conducting a meta-analysis of cohort studies.
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Variable selection and prediction using a nested, matched case-control study: Application to hospital acquired pneumonia in stroke patients.
Biometrics
PUBLISHED: 06-01-2013
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Matched case-control designs are commonly used in epidemiologic studies for increased efficiency. These designs have recently been introduced to the setting of modern imaging and genomic studies, which are characterized by high-dimensional covariates. However, appropriate statistical analyses that adjust for the matching have not been widely adopted. A matched case-control study of 430 acute ischemic stroke patients was conducted at Massachusetts General Hospital (MGH) in order to identify specific brain regions of acute infarction that are associated with hospital acquired pneumonia (HAP) in these patients. There are 138 brain regions in which infarction was measured, which introduce nearly 10,000 two-way interactions, and challenge the statistical analysis. We investigate penalized conditional and unconditional logistic regression approaches to this variable selection problem that properly differentiate between selection of main effects and of interactions, and that acknowledge the matching. This neuroimaging study was nested within a larger prospective study of HAP in 1915 stroke patients at MGH, which recorded clinical variables, but did not include neuroimaging. We demonstrate how the larger study, in conjunction with the nested, matched study, affords us the capability to derive a score for prediction of HAP in future stroke patients based on imaging and clinical features. We evaluate the proposed methods in simulation studies and we apply them to the MGH HAP study.
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D-isoascorbyl palmitate: lipase-catalyzed synthesis, structural characterization and process optimization using response surface methodology.
Chem Cent J
PUBLISHED: 05-09-2013
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Isoascorbic acid is a stereoisomer of L-ascorbic acid, and widely used as a food antioxidant. However, its highly hydrophilic behavior prevents its application in cosmetics or fats and oils-based foods. To overcome this problem, D-isoascorbyl palmitate was synthesized in the present study for improving the isoascorbic acids oil solubility with an immobilized lipase in organic media. The structural information of synthesized product was clarified using LC-ESI-MS, FT-IR, 1H and 13C NMR analysis, and process parameters for high yield of D-isoascorbyl palmitate were optimized by using One-factor-at-a-time experiments and response surface methodology (RSM).
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[Correlation of Eps8 with proliferation, metastasis and prognosis of malignant tumors].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 05-01-2013
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Epidermal growth factor receptor pathway substrate 8 (Eps8) is one of crucial kinase substrates for the epidermal growth factor receptors. Eps8 is related to mitosis and differentiation of normal cells. In recent years, it has been demonstrated that Eps8 involves in proliferation, metastasis and prognosis of many malignant tumors. Experiments have shown that Eps8 involves in Ras-Rac pathway of EGFR signaling by forming Eps8-Abi1-Sos1 tri-complex or participates in endocytosis mediated by rab5. Furthermore, Eps8 has also been found to regulate cell cycle. In conclusion, it may become a monitor and a new target for the treatment of malignant tumors. This review briefly introduces molecular structure and physiological function of Eps8, focusing on its function and molecular mechanism in proliferation, metastasis and prognosis of malignant tumors.
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Immunogenic response induced by wzm and wzt gene deletion mutants from Brucella abortus S19.
Mol Med Rep
PUBLISHED: 04-06-2013
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Brucellosis is an infectious disease affecting humans and animals worldwide. Effective methods of control include inducing immunity in animals by vaccination and elimination. Brucella abortus S19 is one of the popular vaccines for control of cattle brucellosis, as it has low virulence. In this paper, allelic exchange plasmids of wzm and wzt genes were constructed and partially knocked out to evaluate the effects on the induction of immunity to Brucella abortus S19 mutants. Cytokine secretion in vitro, INF-? induction in vivo and antibody dynamics were evaluated. These data suggested that the immunity-eliciting ability of the wzm and wzt gene deletion mutants was similar, although reduced compared with the S19 strain. The results demonstrated that the wzt gene may be more important in the regulation of the induction of immunity than the wzm gene.
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Electrochemically driven biocatalysis of the oxygenase domain of neuronal nitric oxide synthase in indium tin oxide nanoparticles/polyvinyl alcohol nanocomposite.
Bioelectrochemistry
PUBLISHED: 04-02-2013
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Nitric oxide synthase (NOS) plays a critical role in a number of key physiological and pathological processes. Investigation of electron-transfer reactions in NOS would contribute to a better understanding of the nitric oxide (NO) synthesis mechanism. Herein, we describe an electrochemically driven catalytic strategy, using a nanocomposite that consisted of the oxygenase domain of neuronal NOS (D290nNOSoxy), indium tin oxide (ITO) nanoparticles and polyvinyl alcohol (PVA). Fast direct electron transfer between electrodes and D290nNOSoxy was observed with the heterogeneous electron transfer rate constant (ket) of 154.8 ± 0.1s(-1) at the scan rate of 5 Vs(-1). Moreover, the substrate N(?)-hydroxy-L-arginine (NHA) was used to prove the concept of electrochemically driven biocatalysis of D290nNOSoxy. In the presence of the oxygen cosubstrate and tetrahydrobiopterin (BH4) cofactor, the addition of NHA caused the decreases of both oxidation current at +0.1 V and reduction current at potentials ranging from -0.149 V to -0.549 V vs Ag/AgCl. Thereafter, a series of control experiments such as in the absence of BH4 or D290nNOSoxy were performed. All the results demonstrated that D290nNOSoxy biocatalysis was successfully driven by electrodes in the presence of BH4 and oxygen. This novel bioelectronic system showed potential for further investigation of NOS and biosensor applications.
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GL3, a Novel 4?-Anilino-4-O-Demethyl-4-Desoxypodophyllotoxin Analog, Traps Topoisomerase II Cleavage Complexes and Exerts Anticancer Activities.
Transl Oncol
PUBLISHED: 02-01-2013
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A novel VP-16 derivative, 4?-[N -(4?-acetyloxyl-phenyl-1?-carbonyl)-4?-aminoanilino]-4-O-demethyl-4-desoxypodophyllotoxin (GL3), displayed a wide range of cytotoxicity in a panel of human tumor cell lines, with half-maximal inhibitory concentration (IC(50)) values ranging from 0.82 to 4.88 µM, much less than that of VP-16 (4.18-39.43 µM). Importantly, GL3 induces more significant apoptosis and cell cycle arrest than VP-16. The molecular and cellular machinery studies showed that GL3 functions as a topoisomerase II (Top 2) poison through direct binding to the enzyme, and the advanced cell-killing activities of GL3 were ascribed to its potent effects on trapping Top 2-DNA cleavage complex, Moreover, GL3-triggered DNA double-strand breaks and apoptotic cell death were in a Top 2-dependent manner, because the catalytic inhibitor aclarubicin attenuated these biologic consequences caused by Top 2 poisoning in GL3-treated cells. Taken together, among a series of 4?-anilino-4-O-demethyl-4-desoxypodophyllotoxin analog, GL3 stood out by its improved anticancer activity and well-defined Top 2 poisoning mechanisms, which merited the potential value of GL3 as an anticancer lead compound/drug candidate deserving further development.
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Apelin-13 regulates proliferation, migration and survival of retinal Müller cells under hypoxia.
Diabetes Res. Clin. Pract.
PUBLISHED: 01-15-2013
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To investigate the effect of apelin-13 and the antagonist of apelin receptor (F13A) on retinal Müller cells in vitro.
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Diagnostic accuracy of adenosine deaminase for tuberculous peritonitis: a meta-analysis.
Arch Med Sci
PUBLISHED: 01-11-2013
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Tuberculous peritonitis remains a diagnostic challenge for clinicians. Many studies have investigated the usefulness of adenosine deaminase (ADA) in ascites for the diagnosis of tuberculous peritonitis; however, the overall diagnostic accuracy of ADA for tuberculous peritonitis remains unclear. The aim of the present meta-analysis was to determine the overall accuracy of ADA measurements in the diagnosis of tuberculous peritonitis.
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Nitrotyrosine level was associated with mortality in patients with acute kidney injury.
PLoS ONE
PUBLISHED: 01-01-2013
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To examine the characteristics of oxidative stress in patients with acute kidney injury (AKI) and investigate the association between plasma nitrotyrosine levels and 90-day mortality in patients with AKI.
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Hospital acquired pneumonia is linked to right hemispheric peri-insular stroke.
PLoS ONE
PUBLISHED: 01-01-2013
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Hospital acquired pneumonia (HAP) is a major complication of stroke. We sought to determine associations between infarction of specific brain regions and HAP.
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Citrate Pharmacokinetics in Critically Ill Patients with Acute Kidney Injury.
PLoS ONE
PUBLISHED: 01-01-2013
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Regional citrate anticoagulation (RCA) is gaining popularity in continous renal replacement therapy (CRRT) for critically ill patients. The risk of citrate toxicity is a primary concern during the prolonged process. The aim of this study was to assess the pharmacokinetics of citrate in critically ill patients with AKI, and used the kinetic parameters to predict the risk of citrate accumulation in this population group undergoing continuous veno-venous hemofiltration (CVVH) with RCA.
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Is the serum vitamin D level at the time of hospital-acquired acute kidney injury diagnosis associated with prognosis?
PLoS ONE
PUBLISHED: 01-01-2013
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Low circulating vitamin D levels have been suggested to potentially contribute to acute complications in critically ill patients. However, in patients with acute kidney injury (AKI), whether vitamin D deficiency occurs and is a potential contributor to worse early outcomes at the time of AKI diagnosis remains unclear.
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Moxifloxacinium chloride monohydrate.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 09-05-2011
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The title compound {systematic name: 7-[(1S,6S)-8-aza-2-azonia-bicyclo-[4.3.0]non-8-yl]-1-cyclo-propyl-6-fluoro-8-meth-oxy-4-oxo-1,4-dihydro-quinoline-3-carb-oxy-lic acid chloride monohydrate}, C(21)H(25)FN(3)O(4) (+)·Cl(-)·H(2)O, crystallizes with two moxi-floxa-cinium cations, two chloride ions and two uncoordinated water mol-ecules in the unit cell. The crystal structure has a pseudo-inversion center except for the chloride ions. In both moxi-floxa-cinium cations, the quinoline rings are approximately planar, the maximum atomic deviations being 0.107?(3) and 0.118?(3)?Å. The piperidine rings adopt a chair conformation while the pyrrolidine rings display a half-chair conformation. In the crystal, the carboxyl groups, the protonated piperidyl groups, the uncoordinated water mol-ecule and chloride anions participate in O-H?O, O-H?Cl and N-H?Cl hydrogen bonding; weak inter-molecular C-H?O and C-H?Cl hydrogen bonding is also present in the crystal structure.
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Cytokine-induced alterations of ?7 nicotinic receptor in colonic CD4 T cells mediate dichotomous response to nicotine in murine models of Th1/Th17- versus Th2-mediated colitis.
J. Immunol.
PUBLISHED: 07-22-2011
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Ulcerative colitis (UC) and Crohns disease (CD) are two forms of chronic inflammatory bowel disease. CD4 T cells play a central role in the pathogenesis of both diseases. Smoking affects both UC and CD but with opposite effects, ameliorating UC and worsening CD. We hypothesized that the severity of gut inflammation could be modulated through T cell nicotinic acetylcholine receptors (nAChRs) and that the exact clinical outcome would depend on the repertoire of nAChRs on CD4 T cells mediating each form of colitis. We measured clinical and immunologic outcomes of treating BALB/c mice with oxazolone- and trinitrobenzene sulfonic acid (TNBS)-induced colitides by nicotine. Nicotine attenuated oxazolone colitis, which was associated with an increased percentage of colonic regulatory T cells and a reduction of Th17 cells. TCR stimulation of naive CD4(+)CD62L(+) T cells in the presence of nicotine upregulated expression of Foxp3. In marked contrast, nicotine worsened TNBS colitis, and this was associated with increased Th17 cells among colonic CD4 T cells. Nicotine upregulated IL-10 and inhibited IL-17 production, which could be abolished by exogenous IL-12 that also abolished the nicotine-dependent upregulation of regulatory T cells. The dichotomous action of nicotine resulted from the up- and downregulation of anti-inflammatory ?7 nAChR on colonic CD4 T cells induced by cytokines characteristic of the inflammatory milieu in oxazolone (IL-4) and TNBS (IL-12) colitis, respectively. These findings help explain the dichotomous effect of smoking in patients with UC and CD, and they underscore the potential for nicotinergic drugs in regulating colonic inflammation.
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Multianalyte immunoassay chip for detection of tumor markers by chemiluminescent and colorimetric methods.
Anal Bioanal Chem
PUBLISHED: 07-14-2011
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Most cancers developed an elevation of the level of at least two markers associated with their incidence. Simultaneous detection of multi-tumor markers associated with a particular type of cancer plays an important role in cancer diagnostic. Here, a multianalyte immunoassay chip for simple and sensitive detection of tumor markers with chemiluminescent and colorimetric methods was proposed, in which carcinoembryonic antigen (CEA) and carbohydrate antigen (CA19-9) that associated with colorectal cancer were detected as model. The immunoassay chip was fabricated by co-immobilization of CEA/CA19-9 antibody on a glass slide with ?-glycidoxypropyltrimethoxysilane as linkage. Through sandwiched immunoreactions, CEA, CA19-9, and their corresponding enzyme tracers, alkaline phosphatase-labeled anti-CEA and horseradish peroxidase-labeled anti-CA19-9, were introduced on the chip. Then, they were sequentially detected by chemiluminescent method in the range of 0.5-80 ?g/L and 0.5-80 kU/L with the detection limits of 0.41 ?g/L and 0.36 kU/L at 3? for CEA and CA19-9, respectively. They could also be detected by colorimetric method in the range of 1-200 ?g/L and 5-200 kU/L with the detection limits of 0.25 ?g/L and 1.25 kU/L at 3? for CEA and CA19-9, respectively. All these results demonstrated that the present work provided a promising analytical method for tumor markers analysis with the advantages of simple analytical procedure, small sample volume and lower cost, which made the proposed method potential for high-throughput detection.
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Molecular epidemiology of serotype 19A Streptococcus pneumoniae isolated from children in Beijing, 1997-2006.
Chin. Med. J.
PUBLISHED: 07-12-2011
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Despite the prevalence of Streptococcus pneumoniae serotype 19A, the molecular characteristics of this serotype are yet to be fully elucidated. The aim of this study was therefore to determine the homology of the serotype 19A in China.
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Drug synergistic antifertility effect of combined administration of low-dose gossypol with steroid hormones in rats.
Chin. Med. J.
PUBLISHED: 07-12-2011
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Our previous studies suggested that low-dose gossypol combined with steroid hormones has a reversible antifertility role in adult male rats, and the course of treatment was shorter than that of either gossypol or steroid hormones alone. This result suggested that low-dose gossypol and steroid hormones have a drug synergistic effect on antifertility. The aim of the study was to find the target organs of the antifertility synergistic effect of the combined regimen.
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Boundaries of transcriptionally silent chromatin in Saccharomyces cerevisiae.
Genes Genet. Syst.
PUBLISHED: 06-15-2011
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In the budding yeast Saccharomyces cerevisiae, heterochromatic gene silencing has been found within HMR and HML silent mating type loci, the telomeres, and the rRNA-encoding DNA. There may be boundary elements that regulate the spread of silencing to protect genes adjacent to silenced domains from this epigenetic repressive effect. Many assays show that specific DNA regulatory elements separate a euchromatic locus from a neighboring heterochromatic domain and thereby function as a boundary. Alternatively, DNA-independent mechanisms such as competition between acetylated and deacetylated histones are also reported to contribute to gene insulation. However, the mechanism by which boundaries are formed is not clear. Here, the characteristics and functions of boundaries at silenced domains in S. cerevisiae are discussed.
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Simultaneous detection of dual proteins using quantum dots coated silica nanoparticles as labels.
Biosens Bioelectron
PUBLISHED: 05-09-2011
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Simultaneous detection of multianalytes associated with a particular cancer is beneficial for disease diagnosis. Here, a facile immunosensing strategy was designed to allow simultaneous electrochemical detection of dual proteins, in a single run. CdSe and PbS water-soluble quantum dots (QDs) were prepared and coated on monodisperse silica nanoparticles as labels for proteins detection. Rabbit immunoglobulin G antigen (IgG) and carcinoembryonic antigen (CEA) were chosen as model proteins for analysis. After a typical sandwich immunoassay, CdSe and PbS QDs labels were introduced onto the Au substrates surface, which were then dissolved and could be simultaneously monitored by square-wave-voltammetric (SWV) stripping measurements. Under selected conditions, IgG and CEA could be assayed in the ranges of 0.05-40 ng mL(-1) and 0.05-25 ng mL(-1), respectively. The proposed method possessed high sensitivity, good precision, and satisfactory reproducibility and regeneration.
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Febuxostat methanol solvate.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 04-12-2011
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In the title compound {systematic name: [2-(3-cyano-4-isobutyl-oxyphen-yl)-4-methyl-1,3-thia-zole-5-carb-oxy-lic acid (febuxostat) methanol monosolvate}, C(16)H(16)N(2)O(3)S·CH(4)O, the benzene and thia-zole rings in the febuxostat mol-ecule are twisted at 5.3?(1)°. In the crystal structure, inter-molecular O-H?O and O-H?N hydrogen bonds link the febuxostat and methanol mol-ecules into helical chains along the 2(1) screw axis.
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Decreased prothrombin time after intravitreal bevacizumab in the early period in patients with proliferative diabetic retinopathy.
Acta Ophthalmol
PUBLISHED: 04-06-2011
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To evaluate the effect of intravitreal bevacizumab (Avastin; Genentech, Inc., San Francisco, CA, USA) (IVB) injection on prothrombin time (PT) in patients with proliferative diabetic retinopathy (PDR) and nondiabetic patients.
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Efficient double-strand cleavage of DNA mediated by Zn(II)-based artificial nucleases.
Dalton Trans
PUBLISHED: 04-05-2011
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Two water-soluble zinc complexes, [Zn(L)Cl(2)] (1) and [Zn(2)(L)(2)(?-C(2)O(4))(H(2)O)(2)]·(ClO(4))(2)·CH(3)OH (2) (L = N,N-bis(2-pyridylmethyl)methylamine), were prepared to serve as nuclease mimics. The complexes were characterized by X-ray, IR and UV-vis spectroscopy as well as ESI-MS. The electrospray mass spectrum of 2 in solution indicates that dinuclear ion [Zn(2)(L)(2)(?-C(2)O(4))(ClO(4))](+) (3) is the active species. UV-Vis absorption and fluorescence spectroscopy studies show that the complexes partially intercalate to CT-DNA. In the absence of reducing agent, supercoiled plasmid DNA cleavage by the complexes 1 and 3 was performed and the hydrolytic mechanism was demonstrated by adding standard radical scavengers.
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[The efficacy and safety of HAA regimen as induction chemotherapy in 150 newly diagnosed acute myeloid leukemia].
Zhonghua Nei Ke Za Zhi
PUBLISHED: 03-23-2011
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To explore the efficacy and safety of HAA regimen (homoharringtonine, cytarabine and aclarubicin) in the treatment of 150 newly diagnosed adult acute myeloid leukemia (AML).
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What is Visualize?

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

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

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

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