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Find video protocols related to scientific articles indexed in Pubmed.
Differential proteomic analyses of cataracts from rat models of type 1 and 2 diabetes.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 11-20-2014
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PURPOSE. To identify differential changes in proteins and metabolites underlying "fast" type 1 (T1DC) and "slow" type 2 (T2DC) diabetic cataract (DC) formation in rat. METHODS. Rat models of type 1 and 2 diabetes consisted of streptozotocin injection without and with high fat diet, respectively. Cataract progression was examined weekly. At week 6 total protein changes were comparatively and quantitatively assessed by two-dimensional differential in-gel electrophoresis coupled with by mass spectrometry, and relevant metabolic changes were examined. Differences in high molecular weight (HMW) crystallin species between diabetic and control lenses were similarly identified. RESULTS. Cataracts were morphologically different, progressed more slowly in T2DC vs. T1DC. ?A-crystallin, ?B2-crystallin and ?A4-crystallin were significantly decreased in both DC types vs. control. ?B-crystallin was increased while ?B1-crystallin was markedly decreased in T2DC. In T1DC ?B-crystallin and ?S-crystallin fragmentation were increased. High fat diet by itself had little impact, except for lowering ?S-crystallin fragmentation. Despite significantly decreased opacity, a greater decrease in intermediate filaments (IFs) and more HMW crystallin species were observed in T2DC vs. T1DC. However, aldose reductase expression and activity and sorbitol levels were increased to a greater extent in T1DC, while GSH and NADPH levels were decreased to a greater extent, and ATP level was much lower in T1DC vs. T2DC. CONCLUSIONS. The results suggest that osmotic damage, GSH loss and decreased ATP production might be important pathological mechanisms in T1DC formation, whereas crystallin modification and cross-linking/aggregation as well as IF degradation may play more crucial roles in T2DC formation.
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Cadherin controls nectin recruitment into adherens junctions by remodeling the actin cytoskeleton.
J. Cell. Sci.
PUBLISHED: 11-15-2014
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The mechanism that coordinates different adhesion receptors is poorly understood. We investigated this mechanism by focusing on the nectin-2 and E-cadherin adherens junction receptors. Cadherin is not required for the basic process of nectin junction formation since nectin-2 forms junctions in cadherin-deficient A431D cells. Formation of nectin junctions in these cells, however, becomes regulated by cadherin as soon as E-cadherin is reconstituted. E-cadherin recruits nectin-2 into adherens junctions, where both proteins form distinct but tightly associated clusters. Live-cell imaging showed that the appearance of cadherin clusters often precedes that of nectin clusters at sites of junction assembly. Inactivation of cadherin clustering by different strategies concomitantly suppresses the formation of nectin clusters. Furthermore, cadherin significantly increases the stability of nectin clusters, thereby making them resistant to the BC-12 antibody, which targets the nectin-2 adhesion interface. By testing different cadherin-?-catenin chimeras, we showed that the recruitment of nectin into chimera junctions is mediated by the actin-binding domain of ?-catenin. Our data suggests that cadherin regulates-assembly of nectin junctions through ?-catenin-induced remodeling of the actin cytoskeleton around the cadherin clusters.
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Identification of a selective G-quadruplex DNA binder using a multistep virtual screening approach.
Chem. Commun. (Camb.)
PUBLISHED: 11-13-2014
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To efficiently identify small molecules binding to a G-quadruplex structure while avoiding binding to duplex DNA, we performed a multistep structure-based virtual screening by simultaneously taking into account G-quadruplex DNA and duplex DNA. Among the 13 compounds selected, one outstanding ligand shows significant selectivity for G-quadruplex binding as determined using SPR, FRET-based competition and luciferase activity assay.
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[Abnormality of anapastic lymphoma kinase gene and its expression in pediatric neuroblastoma].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 10-28-2014
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To correlate the abnormal expression of anapastic lymphoma kinase (ALK) protein with the genetic and epigenetic changes of ALK, and to analyze its clinical application in pediatric neuroblastoma.
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Elevated levels of protein in urine in adulthood after exposure to the Chinese famine of 1959-61 during gestation and the early postnatal period.
Int J Epidemiol
PUBLISHED: 10-10-2014
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Animal models have suggested that undernutrition during gestation and the early postnatal period may adversely affect kidney development and compromise renal function. As a natural experiment, famines provide an opportunity to test such potential effects in humans. We assessed whether exposure to the Chinese famine of 1959-1961 during gestation and early postnatal life was associated with the levels of proteinuria among female adults three decades after exposure to the famine.
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Visceral and somatic hypersensitivity, autonomic cardiovascular dysfunction and low-grade inflammation in a subset of irritable bowel syndrome patients.
J Zhejiang Univ Sci B
PUBLISHED: 10-09-2014
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The pathophysiology of irritable bowel syndrome (IBS) is complex and not fully understood, so the aim of this study was to evaluate whether visceral and somatic hypersensitivity, autonomic cardiovascular dysfunction, and low-grade inflammation of the gut wall are associated with diarrhea-predominant IBS (D-IBS). Sixty-two patients with D-IBS and 20 control subjects participated in the study. Using the ascending method of limits (AML) protocol, we demonstrated that D-IBS patients had significantly lower sensory thresholds compared with healthy controls (P<0.001). Using diverse methods, especially the ischemic sensitivity test, for the first time in China, we confirmed that D-IBS patients have somatic hypersensitivity. They had a significantly higher systolic blood pressure and heart rate after a cold stimulus, indicative of autonomic cardiovascular dysfunction. Compared with the control group, D-IBS patients had a significantly higher level of calprotectin (P<0.001). We also found significant correlations between visceral and somatic hypersensitivity, visceral hypersensitivity and autonomic cardiovascular dysfunction, and somatic hypersensitivity and autonomic cardiovascular dysfunction. Our findings may provide valuable suggestions for the treatment of D-IBS.
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Statistical Learning Methods for Longitudinal High-dimensional Data.
Wiley Interdiscip Rev Comput Stat
PUBLISHED: 10-07-2014
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Recent studies have collected high-dimensional data longitudinally. Examples include brain images collected during different scanning sessions and time-course gene expression data. Because of the additional information learned from the temporal changes of the selected features, such longitudinal high-dimensional data, when incorporated with appropriate statistical learning techniques, are able to more accurately predict disease status or responses to a therapeutic treatment. In this article, we review recently proposed statistical learning methods dealing with longitudinal high-dimensional data.
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Photocatalytic Oxidation of Aqueous Ammonia Using Atomic Single Layer Graphitic-C3N4.
Environ. Sci. Technol.
PUBLISHED: 10-01-2014
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Direct utilization of solar energy for photocatalytic removal of ammonia from water is a topic of strong interest. However, most of the photocatalysts with effective performance are solely metal-based semiconductors. Here, we report for the first time that a new type of atomic single layer graphitic-C3N4 (SL g-C3N4), a metal-free photocatalyst, has an excellent photocatalytic activity for total ammonia nitrogen (TAN) removal from water. The results demonstrated that over 80% of TAN (initial concentration 1.50 mg·L(-1)) could be removed in 6 h under Xe lamp irradiation (195 mW·cm(-2)). Furthermore, the SL g-C3N4 exhibited a higher photocatalytic activity in alkaline solution than that in neutral or acidic solutions. The investigation suggested that both photogenerated holes and hydroxyl radicals were involved the TAN photocatalytic oxidation process and that the major oxidation product was NO3(-)-N. In addition, SL g-C3N4 exhibited good photocatalytic stability in aqueous solution. This work highlights the appealing application of an inexpensive metal-free photocatalyst in aqueous ammonia treatment.
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Characterization and plasmid elimination of NDM-1-producing Acinetobacter calcoaceticus from China.
PLoS ONE
PUBLISHED: 09-02-2014
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The presence of multidrug-resistant bacterial pathogens in the environment poses a serious threat to public health. The opportunistic Acinetobacter spp. are among the most prevalent causes of nosocomial infections. Here, we performed complete genome sequencing of the Acinetobacter calcoaceticus strain XM1570, which was originally cultivated from the sputum of a patient diagnosed with pneumonia in Xiamen in 2010. We identified carbapenem resistance associated gene bla(NDM-1) located on a 47.3-kb plasmid. Three methods--natural reproduction, sodium dodecyl sulfate treatment and nalidixic acid treatment--were used to eliminate the bla(NDM-1)-encoding plasmid, which achieved elimination rates of 3.32% (10/301), 83.78% (278/332), and 84.17% (298/354), respectively. Plasmid elimination dramatically increased antibiotic sensitivity, reducing the minimum bacteriostatic concentration of meropenem from 256 µg/ml in the clinical strain to 0.125 µg/ml in the plasmid-eliminated strain. Conjugation transfer assays showed that the bla(NDM-1)-containing plasmid could be transferred into Escherichia coli DH5?:pBR322 in vitro as well as in vivo in mice. The bla(NDM-1) genetic environment was in accordance with that of other bla(NDM-1) genes identified from India, Japan, and Hong-Kong. The multilocus sequence type of the isolate was identified as ST-70. Two novel genes encoding intrinsic OXA and ADC were identified and named as OXA-417 and ADC-72. The finding of bla(NDM-1) in species like A. calcoaceticus demonstrates the wide spread of this gene in gram-negative bacteria which is possible by conjugative plasmid transfer. The results of this study may help in the development of a treatment strategy for controlling NDM-1 bacterial infection and transmission.
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Discovery of a new fluorescent light-up probe specific to parallel G-quadruplexes.
Chem. Commun. (Camb.)
PUBLISHED: 09-02-2014
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A novel 2,4,5-triaryl-substituted imidazole (IZCM-1) has been found to display distinct and specific fluorescence enhancement upon binding to parallel G-quadruplexes. Such a sensitive and topology-specific probe is able to light up without affecting the topology or thermal stability of the G-quadruplex sample. Thus, these advantages distinguish IZCM-1 from other G-quadruplex probes.
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[Clinical study in fiberoptic bronchoscopy with a laryngeal mask airway].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 08-27-2014
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To evaluate the usefulness and safety of bronchoscopy by the laryngeal mask airway (LMA) compared with by nose and by mouth.
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A school-based study of irritable bowel syndrome in medical students in beijing, china: prevalence and some related factors.
Gastroenterol Res Pract
PUBLISHED: 08-04-2014
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Purpose. To investigate the prevalence and some related factors about irritable bowel syndrome (IBS) in medical students. Methods. A cross-sectional study was carried out from February 2014 to Jun 2014 in Beijing University of Chinese Medicine, Beijing, China. All participants were asked to completed self-administered questionnaires. Results. Seven hundred and sixty-seven medical students (23.26 ± 2.88 years, 25.6% males) completed the survey. The prevalence of IBS was 33.3%, with a high prevalence in women (36.1%). Among the IBS patients, 112 cases were IBS-M (43.9%) and 77.6% had moderately severe IBS. There were no statistical differences between control group and IBS patients in anxiety and depression scores (P > 0.05). The total score of Pittsburgh sleep quality index (PSQI) was significantly higher for medical students with IBS and 35.5% of IBS patients had severe sleep disorder; the scores of child trauma questionnaire (CTQ) and student-life stress inventory (SLSI) were also higher in IBS patients. Sex and sleep disorder were independently associated with IBS (OR, 1.914, 95%CI, 1.281-2.860; OR, 1.143, 95%CI, 1.074-1.216). Conclusion. Our study has many valuable findings and they may provide valuable suggestions for the necessary intervention and treatment measures towards medical students.
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Photochemical transformation of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) in surface coastal waters: effects of chloride and ferric ions.
Mar. Pollut. Bull.
PUBLISHED: 08-04-2014
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The effects of several aquatic environmental factors on the photochemical transformation of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) have been investigated. Ferric ion (Fe(III)) has been found to promote the phototransformation of BDE-47, and this process is further enhanced with the added chloride ion (Cl(-)), while it is suppressed with increasing pH. Electron spin resonance results show that the formation of hydroxyl radical, and the added Cl(-) could influence the generation of hydroxyl radical in Fe(III) solution. Hence, Cl(-) enhances the phototransformation of BDE-47 most probably because of the reaction with Fe(III) species under irradiation, yielding hydroxyl and chloride radicals. These radicals can not only decompose PBDEs, but also lead to their photodebromination and photochlorination. These results indicate that the aquatic environmental factors and Cl(-) in particular played an important role in the photochemical transformation process of PBDEs, providing insight into the likely fate of PBDEs in the marine environment.
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Early prediction of skin viability using visible diffuse reflectance spectroscopy and autofluorescence spectroscopy.
Plast. Reconstr. Surg.
PUBLISHED: 07-29-2014
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Accurate and early prediction of skin flap viability is vitally important in reconstructive surgery. To the best of the authors' knowledge, this is the first pilot study to evaluate the simultaneous use of both visible diffuse reflectance and autofluorescence spectroscopy on a reverse MacFarlane rat dorsal skin flap model in the early prediction of skin viability.
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Bioelectrochemical enhancement of anaerobic methanogenesis for high organic load rate wastewater treatment in a up-flow anaerobic sludge blanket (UASB) reactor.
Sci Rep
PUBLISHED: 07-25-2014
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A coupling process of anaerobic methanogenesis and electromethanogenesis was proposed to treat high organic load rate (OLR) wastewater. During the start-up stage, acetate removal efficiency of the electric-biological reactor (R1) reached the maximization about 19 percentage points higher than that of the control anaerobic reactor without electrodes (R2), and CH4 production rate of R1 also increased about 24.9% at the same time, while additional electric input was 1/1.17 of the extra obtained energy from methane. Coulombic efficiency and current recorded showed that anodic oxidation contributed a dominant part in degrading acetate when the metabolism of methanogens was low during the start-up stage. Along with prolonging operating time, aceticlastic methanogenesis gradually replaced anodic oxidation to become the main pathway of degrading acetate. When the methanogens were inhibited under the acidic conditions, anodic oxidation began to become the main pathway of acetate decomposition again, which ensured the reactor to maintain a stable performance. FISH analysis confirmed that the electric field imposed could enrich the H2/H(+)-utilizing methanogens around the cathode to help for reducing the acidity. This study demonstrated that an anaerobic digester with a pair of electrodes inserted to form a coupling system could enhance methanogenesis and reduce adverse impacts.
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Negative Regulation of DsbA-L Gene Expression by the Transcription Factor Sp1.
Diabetes
PUBLISHED: 07-14-2014
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Disulfide-bond A oxidoreductase-like protein (DsbA-L) possesses beneficial effects such as promoting adiponectin multimerization and stability, increasing insulin sensitivity, and enhancing energy metabolism. The expression level of DsbA-L is negatively correlated with obesity in mice and humans, but the underlying mechanisms remain unknown. To address this question, we generated reporter gene constructs containing the promoter sequence of the mouse DsbA-L gene. Deletion analysis showed that the proximal promoter of mouse DsbA-L is located between -186 and -34 bp relative to the transcription start site. In silico analysis identified a putative Sp1 transcription factor binding site in the first intron of the DsbA-L gene. Electrophoretic mobility shift assay and chromatin immunoprecipitation analysis indicated that Sp1 bound to this intron region in vitro and in intact cells. Overexpression of Sp1 or suppressing Sp1 expression by siRNA reduced or increased DsbA-L promoter activity, respectively. The binding activity of Sp1 was gradually decreased during 3T3-L1 cell differentiation and was significantly increased in adipose tissues of obese mice. Our results identify Sp1 as an inhibitor of DsbA-L gene transcription, and the Sp1-mediated inhibition of DsbA-L gene expression may provide a mechanism underlying obesity-induced adiponectin downregulation and insulin resistance.
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Enhanced near-infrared to visible upconversion nanoparticles of Ho³?-Yb³?-F? tri-doped TiO? and its application in dye-sensitized solar cells with 37% improvement in power conversion efficiency.
Inorg Chem
PUBLISHED: 07-14-2014
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New near-infrared (NIR)-to-green upconversion nanoparticles of Ho(3+)-Yb(3+)-F(-) tridoped TiO2 (UC-F-TiO2) were designed and fabricated via the hydrosol-hydrothermal method. Under 980 nm NIR excitation, UC-F-TiO2 emit strong green upconversion fluorescence with three emission bands at 543, 644, and 751 nm and convert the NIR light in situ to the dye-sensitive visible light that could effectively reduce the distance between upconversion materials and sensitizers; thus, they minimize the loss of the converted light. Our results show that this UC-F-TiO2 offers excellent opportunities for the other types of solar cells applications, such as organic solar cells, c-Si solar cells, multijunction solar cells, and so on. When integrating the UC-F-TiO2 into dye-sensitized solar cells (DSSCs), superior total energy conversion efficiency was achieved. Under AM1.5G light, open-circuit voltage reached 0.77 ± 0.01 V, short-circuit current density reached 21.00 ± 0.69 mA cm(-2), which resulted in an impressive overall energy conversion efficiency of 9.91 ± 0.30%, a 37% enhancement compared to DSSCs with pristine TiO2 photoanode.
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Systematic reviews on reports of hip fractures in Web of Science: a bibliometric analysis of publication activity.
Chin. Med. J.
PUBLISHED: 07-03-2014
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The objective of this study was to analyze the trend in the publication of systematic reviews on hip fractures through a bibliometric approach.
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Efficient and durable hydrogen evolution electrocatalyst based on nonmetallic nitrogen doped hexagonal carbon.
Sci Rep
PUBLISHED: 07-01-2014
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The feasibility of renewable energy technology, hydrogen production by water electrolysis, depends on the design of efficient and durable electrocatalyst composed of earth-abundant elements. Herein, a highly active and stable nonmetallic electrocatalyst, nitrogen doped hexagonal carbon (NHC), was developed for hydrogen production. It exhibited high activity for hydrogen evolution with a low overpotential of only 65?mV, an apparent exchange current density of 5.7 × 10(-2)?mA cm(-2) and a high hydrogen production rate of 20.8?mL cm(-2) h(-1) at -0.35?V. The superior hydrogen evolution activity of NHC stemmed from the intrinsic electrocatalytic property of hexagonal nanodiamond, the rapid charge transfer and abundance of electrocatalytic sites after nitrogen doping. Moreover, NHC was stable in a corrosive acidic solution during electrolysis under high current density.
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microRNA 490-3P enhances the drug-resistance of human ovarian cancer cells.
J Ovarian Res
PUBLISHED: 06-28-2014
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MicroRNAs (miRNAs) are non-coding, single-stranded small RNAs that regulate gene expression negatively, which is involved in fundamental cellular processes. In this study, we investigated the role of miR-490-3P in the development of drug resistance in ovarian cancer cells.
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Constructing all carbon nanotube hollow fiber membranes with improved performance in separation and antifouling for water treatment.
Environ. Sci. Technol.
PUBLISHED: 06-26-2014
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Manipulating carbon nanotubes (CNTs) through engineering into advanced membranes with superior performance for disinfection and decontamination of water shows great promise but is challenging. In this paper, a facile assembly of CNTs into novel hollow fiber membranes with tunable inner/outer diameters and structures is developed for the first time. These free-standing membranes composed entirely of CNTs feature a porosity of 86±5% and a permeation flux of about 460±50 L m(-2) h(-1) at a pressure differential of 0.04 MPa across the membrane. The randomly oriented interwoven structure of CNTs endows the membranes considerable resistance to pore blockage. Moreover, the adsorption capability of the CNT hollow fiber membranes, which is crucial in the efficient removal of small and trace contaminant molecules, is about 2 orders of magnitude higher than that of commercial polyvinylidene fluoride hollow fiber membranes. The unique advantage of the CNT hollow fiber membranes over other commercial membranes is that they can be in situ electrochemically regenerated after adsorption saturation.
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Recovery of Raman spectra with low signal-to-noise ratio using Wiener estimation.
Opt Express
PUBLISHED: 06-13-2014
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Raman spectroscopy is a powerful non-destructive technique for qualitatively and quantitatively characterizing materials. However, noise often obscures interesting Raman peaks due to the inherently weak Raman signal, especially in biological samples. In this study, we develop a method based on spectral reconstruction to recover Raman spectra with low signal-to-noise ratio (SNR). The synthesis of narrow-band measurements from low-SNR Raman spectra eliminates the effect of noise by integrating the Raman signal along the wavenumber dimension, which is followed by spectral reconstruction based on Wiener estimation to recover the Raman spectrum with high spectral resolution. Non-negative principal components based filters are used in the synthesis to ensure that most variance contained in the original Raman measurements are retained. A total of 25 agar phantoms and 20 bacteria samples were measured and data were used to validate our method. Four commonly used de-noising methods in Raman spectroscopy, i.e. Savitzky-Golay (SG) algorithm, finite impulse response (FIR) filtration, wavelet transform and factor analysis, were also evaluated on the same set of data in addition to the proposed method for comparison. The proposed method showed the superior accuracy in the recovery of Raman spectra from measurements with extremely low SNR, compared with the four commonly used de-noising methods.
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Photodegradation of 2,4-D induced by NO?(-) in aqueous solutions: the role of NO?.
J Environ Sci (China)
PUBLISHED: 06-10-2014
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To elucidate the effect of nitrite ion (NO?(-)) on the photodegradation of organic pollutants, a 300 W mercury lamp and Pyrex tubes restricting the transmission of wavelengths below 290 nm were used to simulate sunlight, and the photodegradation processes of 2,4-dichlorophenoxyacetic acid (2,4-D) with different concentrations of NO?(-) in freshwater and seawater were studied. The effect of reactive oxygen species (ROS) on the photolysis of 2,4-D was also demonstrated using electron paramagnetic resonance (EPR). The results indicated that the 2,4-D photolysis reaction followed the first-order kinetics in freshwater and seawater under different concentrations of NO?(-). Meanwhile, the photochemical reaction rate of 2,4-D increased with increasing concentration of NO?(-). When the concentration of NO?(-) was lower than 23 mg/L, the photodegradation rate of 2,4-D in seawater was higher than that in freshwater. However, when the concentration of NO?(-) was reached 230 mg/L, 2,4-D degradation slowed down in seawater. It was important to note that EPR spectra showed NO? radical was generated in the NO?(-) solution under simulated sunlight irradiation, indicating that 2,4-D photodegradation could be induced by NO?. These results show the key role of NO?(-) in photochemistry and are helpful for better understanding of the phototransformation of environmental contaminants in natural aquatic systems.
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Electrochemiluminescence immunosensor for highly sensitive detection of 8-hydroxy-2'-deoxyguanosine based on carbon quantum dot coated Au/SiO2 core-shell nanoparticles.
Talanta
PUBLISHED: 05-30-2014
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An electrochemiluminescence (ECL) immunosensor using Pt electrode modified with carbon quantum dot (CQDs) coated Au/SiO2 core-shell nanoparticles was proposed for sensitive detection of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in this work. Rabbit anti-8-OHdG antibody was covalently bound to CQDs on the surface of Au/SiO2 core-shell nanoparticles. Through signal amplification of Au/SiO2 core-shell nanoparticles, 8-fold enhancement of the ECL signals was achieved. Under optimal conditions, a good linear range from 0.2 to 200 ng mL(-1) with a low detection limit of 0.085 ng mL(-1) (S/N=3) for 8-OHdG detection was obtained. Interfering substances tests showed that the corresponding ECL intensity (?ECL) of 8-OHdG is 8-18 times higher than that of guanine, uric acid (UA) and ascorbic acid, demonstrating its good selectivity for 8-OHdG detection. The ECL immunosensor exhibits long-term stability with a relative standard deviation (RSD) of 8.5% even after 16 cycles of continuous potential scans. The result of analytical detection of 8-OHdG in real samples was satisfactory. The proposed ECL immunosensor shows good performance with high sensitivity, specificity, repeatability, stability and provided a powerful tool for 8-OHdG monitoring in clinical samples.
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Microgrooved Surface Modulates Neuron Differentiation in Human Embryonic Stem Cells.
Methods Mol. Biol.
PUBLISHED: 05-27-2014
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Stem cell-based therapies have drawn intensive attention in the neuronal regenerative fields. Several studies have revealed that stem cells can serve as an inexhaustible source for neurons for transplantation therapies. However, generation of neurons and directionality has not yet been fully investigated. Herein, we investigate the mechanical ramifications of surface topography on human embryonic cell differentiation. Microgrooved surfaces with various pitches were applied to modulate the neuron differentiation. Our protocol showed that neuron differentiation increased as grove pitch decreased. The results indicated that 2 ?m microgrooves can improve neuron growth by ~1.7-fold. Our results indicate the importance of mechanotransduction on neuronal differentiation and highlight the feasibility of manipulating the neuronal differentiation with surface topography, providing new perspectives for accommodating clinical transplantation.
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Development of a new colorimetric and red-emitting fluorescent dual probe for G-quadruplex nucleic acids.
Chem. Commun. (Camb.)
PUBLISHED: 05-21-2014
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A tailor-made colorimetric and red-emitting fluorescent dual probe for G-quadruplex nucleic acids was developed by incorporating a coumarin-hemicyanine fluorophore into an isaindigotone framework. The significant and distinct changes in both the color and fluorescence of this probe enable the label-free and visual detection of G-quadruplex structures.
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Conductive upconversion Er,Yb-FTO nanoparticle coating to replace Pt as a low-cost and high-performance counter electrode for dye-sensitized solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 05-21-2014
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F-doped SnO2 (FTO) nanocrystals modified by Er and Yb with upconversion capability and excellent catalytic properties have been designed and fabricated as an economic replacement for Pt for use as the counter electrode (CE) in dye-sensitized solar cells. The cost of the UC-FTO counter electrode is only ?(1)/20th of that for Pt. The upconverted luminescence-mediated energy transfer and the superior catalytic property for I3(-)/I(-) circulation overpowered the slight degradation caused by increased CE/electrolyte interface resistance. A 23.9% enhancement in photocurrent was achieved with little degradation in photovoltage, resulting in a 9.12% increase in solar-to-electric power conversion efficiency. Near-infrared (NIR) light-to-electricity has been directly observed by SPS and IPCE characterizations, showing the effect of the upconversion counter electrode.
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Nicotine alters mucin rheological properties.
Am. J. Physiol. Lung Cell Mol. Physiol.
PUBLISHED: 05-16-2014
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Tobacco smoke exposure, the major cause of chronic obstructive pulmonary disease (COPD), instigates a dysfunctional clearance of thick obstructive mucus. However, the mechanism underlying the formation of abnormally viscous mucus remains elusive. We investigated whether nicotine can directly alter the rheological properties of mucin by examining its physicochemical interactions with human airway mucin gels secreted from A549 lung epithelial cells. Swelling kinetics and multiple particle tracking were utilized to assess mucin gel viscosity change when exposed to nicotine. Herein we show that nicotine (?50 nM) significantly hindered postexocytotic swelling and hydration of released mucins, leading to higher viscosity, possibly by electrostatic and hydrophobic interactions. Moreover, the close association of nicotine and mucins allows airway mucus to function as a reservoir for prolonged nicotine release, leading to correlated pathogenic effects. Our results provide a novel explanation for the maltransport of poorly hydrated mucus in smokers. More importantly, this study further indicates that even low-concentration nicotine can profoundly increase mucus viscosity and thus highlights the health risks of secondhand smoke exposure.
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Operative versus nonoperative treatment in complex proximal humeral fractures.
Orthopedics
PUBLISHED: 05-10-2014
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This updated meta-analysis investigated whether operative treatment is superior to nonoperative treatment in complex proximal humeral fractures. The authors searched the Cochrane Central Register of Controlled Trials, PubMed, and EMBASE. Randomized controlled trials that evaluated operative vs nonoperative treatment for exclusively 3- or 4-part proximal humeral fractures were considered. Six studies with a total of 287 patients who had proximal humeral fractures were included. According to the meta-analysis, no statistically significant differences were found between operative and nonoperative treatment in Constant-Murley shoulder scores (Constant scores); Disabilities of the Arm, Shoulder, and Hand scores; total complication events; mortality; infection; nonunion; avascular necrosis; osteoarthritis; redisplacement of fractures; or dislocation or resorption of tuberosity. For health-related quality of life, EuroQol-5D (EQ-5D) favored operative treatment, but 15D scores showed no significant difference. Compared with nonoperative treatment, open reduction and internal fixation required significantly more additional surgeries (risk ratio, 6.50; 95% confidence interval, 1.54-27.50; P=.01), and more penetrations into joint space occurred (risk ratio, 9.56; 95% confidence interval, 2.27-40.13; P=.002). The limited evidence suggests that no convincing findings support the use of either open reduction and internal fixation or hemiarthroplasty for the treatment of complex proximal humeral fractures. The findings of the current study should be interpreted cautiously because of the modest sample size and the short follow-up period.
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Effects of co-treatment with sulforaphane and autophagy modulators on uridine 5'-diphospho-glucuronosyltransferase 1A isoforms and cytochrome P450 3A4 expression in Caco-2 human colon cancer cells.
Oncol Lett
PUBLISHED: 04-25-2014
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Sulforaphane (SFN), which is highly enriched in cruciferous vegetables, has been investigated for its cancer chemopreventive properties and ability to induce autophagy. Uridine 5'-diphospho (UDP)-glucuronosyltransferase (UGT)1A induction is one of the mechanisms that is responsible for the cancer chemopreventive activity of SFN. The current study demonstrates that rapamycin may enhance the chemopreventive effects of SFN on Caco-2 cells; this may be partially attributed to nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2)- and human pregnane X receptor (hPXR)-mediated UGT1A1, UGT1A8 and UGT1A10 induction. These results indicate that targeting autophagy modulation may be a promising strategy for increasing the chemopreventive effects of SFN in cases of colon cancer.
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Lipoxin A4 suppresses the development of endometriosis in an ALX receptor-dependent manner via the p38 MAPK pathway.
Br. J. Pharmacol.
PUBLISHED: 04-18-2014
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Lipoxins can function as endogenous 'breaking signals' in inflammation and play important roles in the progression of endometriosis. In this study, we further investigated the molecular mechanism by which lipoxin A4 (LXA4 ) suppresses the development of endometriosis.
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Functional and molecular features of the calmodulin-interacting protein IQCG required for haematopoiesis in zebrafish.
Nat Commun
PUBLISHED: 04-04-2014
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We previously reported a fusion protein NUP98-IQCG in an acute leukaemia, which functions as an aberrant regulator of transcriptional expression, yet the structure and function of IQCG have not been characterized. Here we use zebrafish to investigate the role of iqcg in haematopoietic development, and find that the numbers of haematopoietic stem cells and multilineage-differentiated cells are reduced in iqcg-deficient embryos. Mechanistically, IQCG binds to calmodulin (CaM) and acts as a molecule upstream of CaM-dependent kinase IV (CaMKIV). Crystal structures of complexes between CaM and IQ domain of IQCG reveal dual CaM-binding footprints in this motif, and provide a structural basis for a higher CaM-IQCG affinity when deprived of calcium. The results collectively allow us to understand IQCG-mediated calcium signalling in haematopoiesis, and propose a model in which IQCG stores CaM at low cytoplasmic calcium concentrations, and releases CaM to activate CaMKIV when calcium level rises.
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Residues and dissipation of trifloxystrobin and its metabolite in tomatoes and soil.
Environ Monit Assess
PUBLISHED: 03-28-2014
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A simple residue analytical method using the quick, easy, cheap, effective, rugged, and safe (QuEChERS) procedure for the determination of trifloxystrobin and its metabolite trifloxystrobin acid (CGA321113) in tomato and soil was developed using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The limits of detection were 0.0005 mg/kg for trifloxystrobin and 0.001 mg/kg for trifloxystrobin acid, respectively. The average recoveries in tomato and soil ranged from 73-99 % for trifloxystrobin and 75-109 % for trifloxystrobin acid, with relative standard deviations below 15 %. The method was then used to study the dissipation and residues in tomato and soil. The dissipation half-lives of trifloxystrobin in tomato were 2.9 days (Beijing) and 5.4 days (Shandong), while in soil were 1.9 days (Beijing) and 3.0 days (Shandong), respectively. The final results showed that the major residue compound was trifloxystrobin in tomato whereas it was its metabolite, trifloxystrobin acid, in soil. The final residues of total trifloxystrobin (including trifloxystrobin acid) were below the EU maximum residue limit of 0.5 mg kg(-1) in tomato 3 days after the treatment.
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Reduction of acute toxicity and genotoxicity of dye effluent using Fenton-coagulation process.
J. Hazard. Mater.
PUBLISHED: 03-11-2014
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Dye wastewater exhibits significant ecotoxicity even though its physico-chemical parameters meet the discharge standards. In this work, the acute toxicity and genotoxicity of dye effluent were tested, and the Fenton-coagulation process was carried out to detoxify this dye effluent. The acute toxicity was evaluated according to the mortality rate of zebrafish, and genotoxicity was evaluated by micronucleus (MN) and comet assays. Removal of color and chemical oxygen demand (COD) was also investigated. The results indicated that the dye effluent showed strong acute toxicity and genotoxicity to zebrafish. After 4h of treatment by Fenton-coagulation process, the dye effluent exhibited no significant acute toxicity and genotoxicity to zebrafish. In addition, its COD was less than 50mg/L, which met the discharge standard. It demonstrates that Fenton-coagulation process can comprehensively reduce the acute toxicity and genotoxicity as well as the COD of the dye effluent.
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The distribution and ultrastructure of the forming blood capillaries and the effect of apoptosis on vascularization in mouse embryonic molar mesenchyme.
Cell Tissue Res.
PUBLISHED: 01-30-2014
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Vascularization is essential for organ and tissue development. Teeth develop through interactions between epithelium and mesenchyme. The developing capillaries in the enamel organ, the dental epithelial structure, occur simultaneously by mechanisms of vasculogenesis and angiogenesis at the onset of dentinogenesis. The vascular neoformation in the dental mesenchyme has been reported to start from the cap stage. However, the mechanisms of vascularization in the dental mesenchyme remain unknown. In the hope of understanding the mechanisms of the formation of dental mesenchymal vasculature, mouse lower molar germs from embryonic day (E) 13.5 to E16.5 were processed for immunostaining of CD31 and CD34, terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) and transmission electron microscopy (TEM). In addition, the role of apoptosis for the vascularization in dental mesenchyme was examined by in vitro culture of E14.0 lower molars in the presence of the apoptosis inhibitor (z-VAD-fmk) and a subsequent subrenal culture. Our results showed that CD31- and CD34-positive cells progressively entered the central part of the dental papilla from the peridental mesenchyme. For TEM, angioblasts, young capillaries with thick endothelium and endothelial cells containing vacuoles were observed in peripheral dental mesenchyme, suggesting vasculogenesis was taking place. The presence of lateral sprouting, cytoplasmic filopodia and transluminal bridges in the dental papilla suggested angiogenesis was also occurring. Inhibition of apoptosis delayed the angiogenic vascularization of the dental papilla. Therefore, these data demonstrated that molar mesenchyme is progressively vascularized by mechanisms of both vasculogenesis and angiogenesis and apoptosis partially contributes to the vascularization of the dental papilla.
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A code for RanGDP binding in ankyrin repeats defines a nuclear import pathway.
Cell
PUBLISHED: 01-22-2014
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Regulation of nuclear import is fundamental to eukaryotic biology. The majority of nuclear import pathways are mediated by importin-cargo interactions. Yet not all nuclear proteins interact with importins, necessitating the identification of a general importin-independent nuclear import pathway. Here, we identify a code that determines importin-independent nuclear import of ankyrin repeats (ARs), a structural motif found in over 250 human proteins with diverse functions. AR-containing proteins (ARPs) with a hydrophobic residue at the 13th position of two consecutive ARs bind RanGDP efficiently, and consequently enter the nucleus. This code, experimentally tested in 17 ARPs, predicts the nuclear-cytoplasmic localization of over 150 annotated human ARPs with high accuracy and is acquired by the most common familial melanoma-associated CDKN2A mutation, leading to nuclear accumulation of mutant p16ink4a. The RaDAR (RanGDP/AR) pathway represents a general importin-independent nuclear import pathway and is frequently used by AR-containing transcriptional regulators, especially those regulating NF-?B/p53.
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Enhanced anaerobic fermentation with azo dye as electron acceptor: Simultaneous acceleration of organics decomposition and azo decolorization.
J Environ Sci (China)
PUBLISHED: 01-07-2014
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Accumulation of hydrogen during anaerobic processes usually results in low decomposition of volatile organic acids (VFAs). On the other hand, hydrogen is a good electron donor for dye reduction, which would help the acetogenic conversion in keeping low hydrogen concentration. The main objective of the study was to accelerate VFA composition through using azo dye as electron acceptor. The results indicated that the azo dye serving as an electron acceptor could avoid H2 accumulation and accelerate anaerobic digestion of VFAs. After adding the azo dye, propionate decreased from 2400.0 to 689.5mg/L and acetate production increased from 180.0 to 519.5mg/L. It meant that the conversion of propionate into acetate was enhanced. Fluorescence in situ hybridization analysis showed that the abundance of propionate-utilizing acetogens with the presence of azo dye was greater than that in a reference without azo dye. The experiments via using glucose as the substrate further demonstrated that the VFA decomposition and the chemical oxygen demand (COD) removal increased by 319.7mg/L and 23.3% respectively after adding the azo dye. Therefore, adding moderate azo dye might be a way to recover anaerobic system from deterioration due to the accumulation of H2 or VFAs.
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Anacardic acid enhances the proliferation of human ovarian cancer cells.
PLoS ONE
PUBLISHED: 01-01-2014
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Anacardic acid (AA) is a mixture of 2-hydroxy-6-alkylbenzoic acid homologs. Certain antitumor activities of AA have been reported in a variety of cancers. However, the function of AA in ovarian cancer, to date, has remained unknown.
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[Early removal of the chest tube after lobectomies: a prospective randomized control study].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 10-05-2013
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To evaluate the feasibility and safety of early chest tube removal after lobectomies for lung diseases.
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Genetic incorporation of a 2-naphthol group into proteins for site-specific azo coupling.
Bioconjug. Chem.
PUBLISHED: 10-02-2013
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The 2-naphthol analogue of tyrosine, 2-amino-3-(6-hydroxy-2-naphthyl)propanoic acid (NpOH), has been genetically introduced into proteins in Escherichia coli . This is achieved through the directed evolution of orthogonal aminoacyl-tRNA synthetase/tRNA pairs that selectively charge the target amino acid in response to the amber stop codon, UAG. Moreover, chemoselective azo coupling reactions have been revealed between the 2-naphthol group and diazotized aniline derivatives that are substituted with an electron donating moiety. The coupling reactions required a very mild condition (pH 7) with great reaction rate (less than 2 h at 0 °C), high efficiency, and excellent selectivity.
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Vitamin D Controls Murine and Human Plasmacytoid Dendritic Cell Function.
J. Invest. Dermatol.
PUBLISHED: 09-06-2013
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Topical application of the vitamin D (VitD) analog calcipotriol is a highly effective standard treatment modality of psoriatic skin lesions. However, the immune modulatory effects of the treatment are incompletely understood. VitD is well known to induce tolerogenic responses in conventional dendritic cells (cDCs). Plasmacytoid DCs (pDCs) comprise a specialized, naturally occurring DC subset known to be important in autoimmune diseases including psoriasis. pDCs from the blood rapidly infiltrate psoriatic skin and are key to the initiation of the immune-mediated pathogenesis of the disease. We now demonstrate that pDCs express various proteins of the VitD receptor (VDR) pathway, including the VitD-metabolizing enzymes Cyp27B1 and Cyp24A1, and that VDR is transcriptionally active in pDCs. Moreover, VitD impairs the capacity of murine and human pDCs to induce T-cell proliferation and secretion of the T-helper 1 cytokine IFN?. The inhibitory effect of VitD is dependent on the expression of the VDR in the DCs. This study demonstrates that VitD signaling can act as a natural inhibitory mechanism on both cDCs and pDCs, which may instigate the development of VitD-based therapeutic applications for psoriasis and other inflammatory skin diseases.Journal of Investigative Dermatology advance online publication, 19 December 2013; doi:10.1038/jid.2013.501.
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The Involvement of RhoA and Wnt-5a in the Tumorigenesis and Progression of Ovarian Epithelial Carcinoma.
Int J Mol Sci
PUBLISHED: 08-29-2013
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Background: Ras homolog gene family member A (RhoA) is involved in Wnt-5a-induced migration of gastric and breast cancer cells. We investigated the roles of RhoA and Wnt-5a in ovarian carcinoma. Methods: RhoA and Wnt-5a mRNA and protein expression in normal fallopian tube epithelium, benign tumors, primary ovarian carcinomas, and metastatic omentum were quantified. RhoA or Wnt-5a was knocked down in OVCAR3 ovarian carcinoma cells using siRNAs and cell phenotype and expression of relevant molecules were assayed. Results: RhoA and Wnt-5a mRNA and protein expression were found to be significantly higher in metastatic omentum than in ovarian carcinomas, benign tumors, and normal fallopian tube epithelium (p < 0.05), and positively associated with differentiation and FIGO staging (stage I/II vs. stage III/IV) in ovarian carcinoma (p < 0.05). RhoA and Wnt-5a expression were positively correlated in ovarian carcinoma (p = 0.001, R2 = 0.1669). RhoA or Wnt-5a knockdown downregulated RhoA and Wnt-5a expression; reduced cell proliferation; promoted G1 arrest and apoptosis; suppressed lamellipodia formation, cell migration, and invasion; and reduced PI3K, Akt, p70S6k, Bcl-xL, survivin, and VEGF mRNA or protein expression. Conclusions: This is the first demonstration that RhoA and Wnt-5a are associated with ovarian carcinogenesis and apoptosis inhibition; there might be positive correlation between RhoA and Wnt-5a expression. RhoA is a potential tumorigenesis, differentiation, and progression biomarker in ovarian carcinoma.
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Employing bifunctional enzymes for enhanced extraction of bioactives from plants: flavonoids as an example.
J. Agric. Food Chem.
PUBLISHED: 08-09-2013
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A cost-effective and environmentally friendly approach was developed to improve the extraction of active ingredients from plants, in which a bifunctional enzyme was employed for not only facilitating cell wall degradation but also increasing the bioactivity of target compounds in the extract. In the aqueous extraction of flavonoids from Glycyrrhizae radix, Trichoderma viride cellulase, a commercial cell-wall-degrading enzyme, was found to efficiently deglycosylate liquiritin and isoliquiritin, which are of high content but low bioactivity, into their aglycones that have much higher physiological activities for dietary and medicinal uses. Under optimized conditions, the extraction yield of liquiritigenin and isoliquiritigenin aglycones reached 4.23 and 0.39 mg/g of dry weight (dw) with 6.51- and 3.55-fold increases, respectively. The same approach was expanded to the extraction of flavonoids from Scutellariae radix using Penicillium decumbens naringinase, where enhanced production of more bioactive bacalein and wogonin was achieved via enzymatic deglycosylation of bacalin and wogonoside.
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The role of EMMPRIN expression in ovarian epithelial carcinomas.
Cell Cycle
PUBLISHED: 08-08-2013
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Extracellular matrix metalloproteinase inducer (EMMPRIN) was reported to involve in the invasion and metastasis of malignancies by regulating the expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs) in stromal and cancer cells. The study aimed to clarify the role of EMMPRIN expression in tumorigenesis and progression of ovarian epithelial carcinomas.
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Nitrogen-doped diamond electrode shows high performance for electrochemical reduction of nitrobenzene.
J. Hazard. Mater.
PUBLISHED: 08-07-2013
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Effective electrode materials are critical to electrochemical reduction, which is a promising method to pre-treat anti-oxidative and bio-refractory wastewater. Herein, nitrogen-doped diamond (NDD) electrodes that possess superior electrocatalytic properties for reduction were fabricated by microwave-plasma-enhanced chemical vapor deposition technology. Nitrobenzene (NB) was chosen as the probe compound to investigate the materials electro-reduction activity. The effects of potential, electrolyte concentration and pH on NB reduction and aniline (AN) formation efficiencies were studied. NDD exhibited high electrocatalytic activity and selectivity for reduction of NB to AN. The NB removal efficiency and AN formation efficiency were 96.5% and 88.4% under optimal conditions, respectively; these values were 1.13 and 3.38 times higher than those of graphite electrodes. Coulombic efficiencies for NB removal and AN formation were 27.7% and 26.1%, respectively; these values were 4.70 and 16.6 times higher than those of graphite electrodes under identical conditions. LC-MS analysis revealed that the dominant reduction pathway on the NDD electrode was NB to phenylhydroxylamine (PHA) to AN.
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Effect of aluminum on the thermoelectric properties of nanostructured PbTe.
Nanotechnology
PUBLISHED: 08-06-2013
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In the present work, the effect of aluminum (Al) on the thermoelectric properties of PbTe is studied. Aluminum doped PbTe samples, fabricated by a ball milling and hot pressing, have Seebeck coefficients between -100 and -200 ?V K-1 and electrical conductivities of (3.6-18) × 104 S m-1 at room temperature, which means that Al is an effective donor in PbTe. The first principle calculations clearly show an increase of the density of states close to the Fermi level in the conduction band due to Al doping, which averages up the energy and effective mass of electrons, resulting in enhancement of the Seebeck coefficient. The maximum figure-of-merit ZT of 1.2 is reached at 770 K in the Al0.03PbTe sample.
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Aberrant Beclin 1 expression is closely linked to carcinogenesis, differentiation, progression, and prognosis of ovarian epithelial carcinoma.
Tumour Biol.
PUBLISHED: 07-26-2013
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Beclin 1, an important autophagy-related protein in human cells, is involved in autophagy, differentiation, anti-apoptosis, and cancer suppression, which is increased during periods of cell stress and extinguished during cell cycle. Human ovarian tumors display allelic loss of Beclin 1 with high frequency. To clarify Beclin 1s role in ovarian carcinogenesis and subsequent progression, its expression was examined by immunostaining on tissue microarrays containing ovarian normal tissue, benign and borderline tumors, and carcinomas. Beclin 1 mRNA and protein expression was examined in ovarian normal tissue, benign and borderline tumors, carcinoma tissue, and cell lines by reverse transcription polymerase chain reaction or Western blot, respectively. The results demonstrated that the higher Beclin 1 mRNA was observed in ovarian benign tumor than normal ovary and ovarian carcinoma (P??0.05). It was suggested that the aberrant Beclin 1 expression is closely linked to tumorigenesis and differentiation of ovarian carcinoma. Beclin 1 expression might be employed to indicate the worse prognosis of ovarian carcinomas, albeit not an independent factor.
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Electrochemically enhanced adsorption of nonylphenol on carbon nanotubes: Kinetics and isotherms study.
J Colloid Interface Sci
PUBLISHED: 07-25-2013
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Removal of nonylphenol (NP) from aqueous solution has attracted widely attention due to its aquatic toxicity and potential to disrupt the endocrine system. In an effort to develop the effective and environment-friendly treatment method for NP, adsorption of 4-n-nonylphenol (4-NP) on multi-walled carbon nanotubes (MWCNTs) under electrochemical assistance was studied. The adsorption kinetics and isotherms were investigated at different polarization potentials and compared with those of open circuit (OC) and powder MWCNTs adsorption. The adsorption kinetics was simulated by the model including pseudo-first-order model, pseudo-second-order model and intraparticle diffusion model. The isotherm was simulated with Langmuir model and Freudlich model, respectively. Experimental results indicated that 4-NP is able to be efficiently removed at a potential of -0.6V. Comparing with that of powder MWCNTs adsorption, the initial adsorption rate ?0 at -0.6V increased 7.9-fold according to pseudo-second-order model and the maximum adsorption capacity qm improved 1.7-fold according to Langmuir model. The improved adsorption effect at negative potential was ascribed to enhanced ?-? electron-donor-acceptor (EDA) interaction between 4-NP and MWCNTs under electrochemical assistance.
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[Effects of autophagy modulator on autophagy and uridine 5-diphospho-glucuronosyltransferase 1A1 induced by sulforaphane].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 05-14-2013
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To explore the effects of 3-methyladenine (3-MA) and rapamycin (Rapa) on autophagy and uridine 5-diphospho-glucuronosyltransferase 1A1 (UGT1A1) induced by sulforaphane (SFN) in human colon cancer Caco-2 cells.
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BTG1 expression correlates with the pathogenesis and progression of ovarian carcinomas.
Int J Mol Sci
PUBLISHED: 05-13-2013
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BTG (B-cell translocation gene) can inhibit cell proliferation, metastasis, and angiogenesis and regulate cell cycle progression and differentiation in a variety of cell types. We aimed to clarify the role of BTG1 in ovarian carcinogenesis and progression. A BTG1-expressing plasmid was transfected into ovarian carcinoma cells and their phenotypes and related proteins were examined. BTG1 mRNA expression was detected in ovarian normal tissue (n = 17), ovarian benign tumors (n = 12), and ovarian carcinoma (n = 64) using real-time RT-PCR. Ectopic BTG1 expression resulted in lower growth rate, high cisplatin sensitivity, G1 arrest, apoptosis, and decreased migration and invasion. Phosphoinositide 3-kinase, protein kinase B, Bcl-xL, survivin, vascular endothelial growth factor, and matrix metalloproteinase-2 mRNA and protein expression was reduced in transfectants as compared to control cells. There was higher expression of BTG1 mRNA in normal tissue than in carcinoma tissue (p = 0.001) and in benign tumors than in carcinoma tissue (p = 0.027). BTG1 mRNA expression in International Federation of Gynecology and Obstetrics (FIGO) stage I/II ovarian carcinomas was higher than that in FIGO stage III/IV ovarian carcinomas (p = 0.038). Altered BTG1 expression might play a role in the pathogenesis and progression of ovarian carcinoma by modulating proliferation, migration, invasion, the cell cycle, and apoptosis.
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Efficacy and Safety of Iguratimod for the Treatment of Rheumatoid Arthritis.
Clin. Dev. Immunol.
PUBLISHED: 05-01-2013
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All randomized controlled trials (RCTs) of iguratimod for rheumatoid arthritis (RA) to assess its efficacy and safety are included in this paper. The Review Manager software was used for meta-analysis to assess risk bias of the studies included, and GRADE profiler software was used for the evidence quality of the studies included. Four RCTs involving 1407 patients with RA were included. Meta-analyses showed that, after 24-week therapy, ACR20, tender joint count, swollen joint count, rest pain, physician and patient global assessment of disease activity, HAQ score, ESR, and CRP in iguratimod group were better than those in placebo group and that the difference between those of iguratimod group and those of other DMARDs (MTX and SASP) group was not significant. GRADE evidence classification of the studies included was moderate. Iguratimod for RA had few adverse events, and its efficacy and safety were the same as those of MTX and SASP for RA. The results of this systematic review suggest that more high-quality and large-scaled RCTs were needed to determine the efficacy of iguratimod for RA and whether iguratimod is as effective as other DMARDs besides MTX and SASP.
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Complete Genome Sequence of an Acinetobacter Strain Harboring the NDM-1 Gene.
Genome Announc
PUBLISHED: 04-20-2013
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The NDM-1 gene is a significant public health concern. Acinetobacter is one of the most prevalent opportunistic pathogens causing recent nosocomial infections with NDM-1, and drug-resistant strains pose serious threats to public health worldwide. Herein, we present the genomic sequence of Acinetobacter calcoaceticus subsp. anitratus XM1570, a multidrug-resistant isolate that carries the blaNDM-1 gene.
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Probucol inhibits JAK2-STAT pathway activation and protects human glomerular mesangial cells from tert-butyl hydroperoxide induced premature senescence.
Can. J. Physiol. Pharmacol.
PUBLISHED: 04-08-2013
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Human mesangial cells (HMCs) have a finite lifespan and eventually enter irreversible growth arrest known as cellular senescence, which is thought to contribute to kidney ageing and age-related kidney disorders such as chronic kidney disease. The JAK2-STAT pathway plays a pivotal role in transmitting cytokine signals, including cell proliferation, apoptosis, and differentiation, but whether it could regulate HMC senescence still remains to be explored. In our study, tert-butyl hydroperoxide (tBHP)-induced cells accelerated HMC senescence, as judged by increased senescence-associated ?-galactosidase stained positive cells, morphological changes, and G0-G1 cell cycle arrest. STAT1 and STAT3 activity were increased in tBHP-induced cells. After tBHP treatment, Bcl-2 protein expression decreased and Bax protein expression increased. Blocking the JAK2-STAT pathway with AG490 and using probucol significantly inhibited the progression of HMC senescence. Bax protein expression decreased, but Bcl-2 protein expression increased after AG490 and probucol treatment. Our results indicated that the JAK2-STAT pathway might mediate tBHP-induced HMC senescence through the Bcl-2-Bax pathway, and that probucol could attenuate HMC senescence by regulating STATs.
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Distinct radiosensitivity of lung carcinoma stem-like side population and main population cells.
Cancer Biother. Radiopharm.
PUBLISHED: 03-20-2013
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Lung cancer is a leading cause of cancer death worldwide. Efficacy of radiation therapy on lung cancer is hindered by many factors. Among these, both cancer stem-like side population (SP) and main population (MP) cells may contribute to tumorigenesis and resistance to radiation therapy. However, the detailed mechanism responsible for this effect remains unknown.
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Immortalized mouse dental papilla mesenchymal cells preserve odontoblastic phenotype and respond to bone morphogenetic protein 2.
In Vitro Cell. Dev. Biol. Anim.
PUBLISHED: 03-15-2013
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Odontogenesis is the result of the reciprocal interactions between epithelial-mesenchymal cells leading to terminally differentiated odontoblasts. This process from dental papilla mesenchymal cells to odontoblasts is regulated by a complex signaling pathway. When isolated from the developing tooth germs, odontoblasts quickly lose their potential to maintain the odontoblast-specific phenotype. Therefore, generation of an odontoblast-like cell line would be a good surrogate model for studying the dental mesenchymal cell differentiation into odontoblasts and the molecular events of dentin formation. In this study, immortalized dental papilla mesenchymal cell lines were generated from the first mouse mandibular molars at postnatal day 3 using pSV40. These transformed cells were characterized by RT-PCR, immunohistochemistry, Western blot, and analyzed for alkaline phosphatase activity and mineralization nodule formation. One of these immortalized cell lines, iMDP-3, displayed a high proliferation rate, but retained the genotypic and phenotypic characteristics similar to primary cells as determined by expression of tooth-specific markers and demonstrated the ability to differentiate and form mineralized nodules. Furthermore, iMDP-3 cells had high transfection efficiency as well as were inducible and responded to BMP2 stimulation. We conclude that the establishment of the stable murine dental papilla mesenchymal cell line might be used for studying the mechanisms of dental cell differentiation and dentin formation.
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Active inclusion bodies of acid phosphatase PhoC: aggregation induced by GFP fusion and activities modulated by linker flexibility.
Microb. Cell Fact.
PUBLISHED: 03-01-2013
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Biologically active inclusion bodies (IBs) have gained much attention in recent years. Fusion with IB-inducing partner has been shown to be an efficient strategy for generating active IBs. To make full use of the advantages of active IBs, one of the key issues will be to improve the activity yield of IBs when expressed in cells, which would need more choices on IB-inducing fusion partners and approaches for engineering IBs. Green fluorescent protein (GFP) has been reported to aggregate when overexpressed, but GFP fusion has not been considered as an IB-inducing approach for these fusion proteins so far. In addition, the role of linker in fusion proteins has been shown to be important for protein characteristics, yet impact of linker on active IBs has never been reported.
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The role of RhoC in ovarian epithelial carcinoma: a marker for carcinogenesis, progression, prognosis, and target therapy.
Gynecol. Oncol.
PUBLISHED: 02-20-2013
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Ras homolog gene family member C (RhoC) is a small G protein/guanosine triphosphatase involved in tumor mobility, invasion, and metastasis.
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miR-145 and miR-143 regulate odontoblast differentiation through targeting Klf4 and Osx genes in a feedback loop.
J. Biol. Chem.
PUBLISHED: 02-19-2013
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Dentin tissue is derived from mesenchymal cells induced into the odontoblast lineage. The differentiation of odontoblasts is a complex process regulated by several transcriptional factor signaling transduction pathways. However, post-translational regulation of these factors during dentinogenesis remains unclear. To further explore the mechanisms, we investigated the role of microRNA (miRNA) during odontoblast differentiation. We profiled the miRNA expression pattern during mouse odontoblast differentiation using a microarray assay and identified that miR-145 and miR-143 were down-regulated during this process. In situ hybridization verified that the two miRNAs were gradually decreased during mouse odontoblast differentiation. Loss-of-function and gain-of-function experiments revealed that down-regulation of miR-145 and miR-143 could promote odontoblast differentiation and increased Dspp and Dmp1 expression in mouse primary dental pulp cells and vice versa. We found that miR-145 and miR-143 controlled odontoblast differentiation through several mechanisms. First, KLF4 and OSX bind to their motifs in Dspp and Dmp1 gene promoters and up-regulate their transcription thereby inducing odontoblast differentiation. The miR-145 binds to the 3-UTRs of Klf4 and Osx genes, inhibiting their expression. Second, KLF4 repressed miR-143 transcription by binding to its motifs in miR-143 regulatory regions as detected by ChIP assay and dual luciferase reporter assay. Third, miR-143 regulates odontoblast differentiation in part through miR-145 pathway. Taken together, we for the first time showed that the miR-143 and miR-145 controlled odontoblast differentiation and dentin formation through KLF4 and OSX transcriptional factor signaling pathways.
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Short- and long-term changes of condylar position after bilateral sagittal split ramus osteotomy for mandibular advancement in combination with Le Fort I osteotomy evaluated by cone-beam computed tomography.
J. Oral Maxillofac. Surg.
PUBLISHED: 02-17-2013
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Bilateral sagittal split ramus osteotomy (BSSO) may change condylar position, which can be one of the factors contributing to skeletal relapse. This study evaluated short- and long-term changes in condylar position using cone-beam computed tomography (CBCT) and investigated changes in temporomandibular joint (TMJ) signs after BSSO for mandibular advancement in combination with Le Fort I osteotomy.
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Effects of ferric iron on the anaerobic treatment and microbial biodiversity in a coupled microbial electrolysis cell (MEC)--anaerobic reactor.
Water Res.
PUBLISHED: 02-15-2013
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Adding Fe(III) into a MEC - anaerobic reactor enhanced the degradation of organic matters. To clarify the respective effects of combining Fe(III) dosage and a MEC and Fe(III) dosage only on strengthening anaerobic digestion, three anaerobic reactors were operated in parallel: a MEC - anaerobic reactor with dosing Fe(OH)3 (R1), an anaerobic reactor with dosing Fe(OH)3 (R2) and a common anaerobic reactor (R3). With increasing influent COD from 1500 to 4000 mg/L, the COD removal in R1 was maintained at 88.3% under a voltage of 0.8 V, which was higher than that in reactor R2 and R3. When the power was cut off, the COD removal in R1 decreased by 5.9%. The addition of Fe(OH)3 enhanced both anaerobic digestion and anodic oxidation, resulting in the effective mineralization of volatile fatty acids (VFAs). The reduced Fe(II) combined with electric field resulted more extracellular polymeric substances (EPS) production. Quantitative real - time PCR showed a higher abundance of bacteria in the anodic biofilm and R1. Pyrosequencing and denaturing gradient gel electrophoresis (DGGE) analysis revealed that the dominant bacteria and archaea communities were richer and more abundant in the anode biofilm and R1.
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Integrin-facilitated transcytosis for enhanced penetration of advanced gliomas by poly(trimethylene carbonate)-based nanoparticles encapsulating paclitaxel.
Biomaterials
PUBLISHED: 02-04-2013
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The treatment of cerebral tumor, especially advanced gliomas, represents one of the most formidable challenges in oncology. In this study, integrin-mediated poly(trimethylene carbonate)-based nanoparticulate system (c(RGDyK)-NP) was proposed as a delivery vehicle for enhancing drug penetration and chemotherapy of malignant gliomas. Following the recognition by integrin proteins on cell surface, c(RGDyK)-NP could be energy-dependently internalized by human U87MG glioma cells through a multiple endocytic pathway. The tumor penetration, homing specificity and anticancer efficacy of PTX-loaded c(RGDyK)-NP (c(RGDyK)-NP/PTX) were performed on the 3D glioma spheroids, the U87MG glioma cells and the intracranial glioma mice model, respectively. Compared with conventional nanoparticles (NP/PTX) and Taxol, c(RGDyK)-NP/PTX showed the strongest penetration and accumulation into 3D glioma spheroids, an obvious microtubule stabilization effect to U87MG glioma cells, a significant homing specificity to malignant glioma in vivo, and an extended median survival time in the intracranial glioma-bearing mice. Furthermore, preliminary in vivo subacute toxicity was also evaluated by measuring the histopathology, blood cell counts and clinical biochemistry parameters, and the results revealed no obvious subacute toxicity to hematological system, major organs or tissues were observed post successive intravenous injection of c(RGDyK)-NP. Therefore, our results suggested that cyclic RGD-conjugated PEG-PTMC nanoparticle could be a promising vehicle for enhancing the penetration and cxhemotherapy of high-grade malignant gliomas.
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Decreased expression of BTG3 was linked to carcinogenesis, aggressiveness, and prognosis of ovarian carcinoma.
Tumour Biol.
PUBLISHED: 02-01-2013
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B-cell translocation gene 3 (BTG3) is a member of the BTG family which inhibits cell proliferation, metastasis, and angiogenesis, and also regulates cell-cycle progression and differentiation in a variety of cell types. However, there is no study to analyze BTG3 expression in epithelial ovarian carcinoma (EOC). Here, we investigated the expression of BTG3 in EOC carcinogenesis and subsequent progression. BTG3 mRNA expression was detected by real-time RT-PCR in ovarian benign and malignant tumors. The expression of BTG3 protein was examined by immunohistochemistry on tissue microarrays containing ovarian normal tissue, benign and borderline epithelial ovarian tumors, and EOCs. Relationships of BTG3 with both EOC clinicopathology and prognosis were analyzed statistically. The expression of BTG3 protein was also evaluated in ovarian normal tissue, benign tumors, and EOCs by western blot. The BTG3 mRNA expression level was higher in ovarian normal tissue and benign tumors than that in borderline, primary, and metastatic carcinoma (p < 0.05), and was negatively correlated with dedifferentiation and FIGO staging of EOC (p < 0.05). Using western blot, BTG3 protein was found lower in EOCs compared to the normal and benign tumors (p < 0.05), and poorly differentiated EOCs showed lower BTG3 expression than well-differentiated and moderately differentiated EOCs (p < 0.05). Immunohistochemically, BTG3 protein expression was statistically lower in EOCs than normal tissue and benign tumors (p < 0.05). EOC patients with low BTG3 protein expression showed a higher incidence of metastasis (p = 0.020), poor differentiation (p = 0.030), and shorter disease-free time and overall survival time (p < 0.05). By using Coxs proportional hazard model, BTG3 protein expression and FIGO staging were independent prognostic factors for both disease-free time and overall survival time of EOCs (p < 0.05). It was suggested that down-regulated BTG3 expression might play roles in the pathogenesis and aggressiveness of EOC. BTG3 protein expression may be considered as a good marker to indicate the favorable prognosis of EOCs.
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Measurement of operator exposure to chlorpyrifos.
Pest Manag. Sci.
PUBLISHED: 01-30-2013
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To date, no research has been conducted to establish exposure levels for occupational pesticide operators under typical use scenarios in China. Through surrogate skin techniques (the whole-body method), the authors monitored dermal and inhalation exposure of pesticide applicators in China. In addition, the exposure of pesticide mixers was analysed.
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Polymorphic expression of UDP-glucuronosyltransferase UGTlA gene in human colorectal cancer.
PLoS ONE
PUBLISHED: 01-16-2013
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Polymorphism of genes encoding drug-metabolizing enzymes is known to play an important role in increased susceptibility of colorectal cancer. UGT1A gene locus has been suggested to define tissue-specific glucuronidation activity. Reduced capacity of glucuronidation is correlated with the development of colorectal cancer. Therefore, we sought to explore polymorphism of UGTlA gene in human colorectal cancer.
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Enhanced anaerobic digestion of organic contaminants containing diverse microbial population by combined microbial electrolysis cell (MEC) and anaerobic reactor under Fe(III) reducing conditions.
Bioresour. Technol.
PUBLISHED: 01-07-2013
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Microbial electrolysis cell (MEC) devices are efficient for wastewater treatment, but its application was limited due to low anode oxidation rate. The objective of this study was to improve anode performance of a MEC combined anaerobic reactor (R1) for high concentration industrial wastewater treatment via dosing Fe(OH)3. For the first 53 days without power, the addition of Fe(OH)3 in R1 enhanced the degradation of reactive brilliant red X-3B dye and sucrose. Applying a voltage of 0.8 V in R1 resulted in a higher decolorization and COD removal through driving the redox reactions at electrodes under Fe(III)-reducing conditions. Real-time PCR and enzyme activity analysis showed that the abundance and azoreductase activity of bacteria were improved in R1. Pyrosequencing revealed that dominant populations in anode biofilm and R1 were more diverse and abundant than the common anaerobic reactor (R2), and there was a significant distinction among anode film, R1 and R2 in microbial community structure.
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Co-Relationships between glandular salivary flow rates and dental caries.
Gerodontology
PUBLISHED: 01-04-2013
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OBJECTIVE: This study was designed to evaluate the relationship of age, gender, ethnicity and salivary flow rates on dental caries in an adult population using data collected from the Oral Health San Antonio Longitudinal Study of Aging (OH: SALSA). BACKGROUND: Saliva is essential to maintain a healthy oral environment and diminished output can result in dental caries. Although gender and age play a role in the quantity of saliva, little is known about the interaction of age, gender and ethnicity on dental caries and salivary flow rates. MATERIALS AND METHODS: Data from the 1147 participants in the OH: SALSA were analysed. The dependent variables were the number of teeth with untreated coronal caries, number of teeth with root caries and the number of coronal and root surfaces with untreated caries. The independent variables were stimulated and unstimulated glandular salivary flow rates along with the age, sex and ethnicity (e.g. European or Mexican ancestry) of the participants. RESULTS: Coronal caries experience was greater in younger participants while root surface caries experience was greater in the older participants. Coronal caries was lower in the older age groups while the root caries experience increased. Men had a statistically significant (p < 0.02) higher experience of root caries than women. Values for unstimulated and stimulated parotid salivary flow rates showed no age difference and remained constant with age, whereas the age differences in the unstimulated and stimulated submandibular/sublingual salivary flow rates were significant. The mean number of teeth with coronal and root caries was higher in Mexican-Americans than in European-Americans. CONCLUSIONS: Over one-fourth of the adults between the ages of 60 and 79 have untreated root caries over one-third having untreated coronal caries. Lower salivary flow rates play a significant role in both the number of teeth and the number of surfaces developing caries in these adults. Women and individuals of European-American ancestry experience less caries.
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Synthesis of C-13-labeled atrazine.
J Labelled Comp Radiopharm
PUBLISHED: 01-02-2013
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Atrazine is a long-lasting herbicide that has been shown to affect hormone levels in amphibians. Using the C-13 labeled atrazine to detect its residue is effective and essential. This study presents three steps for the synthesis of [(13) C3 ]atrazine, which starts from [(13) C]urea, and results in the incorporation of C-13 atoms at the 1, 3 and 5 positions of the S-triazine ring of atrazine. The method prepares the product in an overall yield of 57.6% and chemical purity of 98.6%, for use as an internal standard. Copyright © 2013 John Wiley & Sons, Ltd.
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The Anti-Tumor Effects and Molecular Mechanisms of Suberoylanilide Hydroxamic Acid (SAHA) on the Aggressive Phenotypes of Ovarian Carcinoma Cells.
PLoS ONE
PUBLISHED: 01-01-2013
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Histone deacetylase inhibitors (HDACi), such as suberoylanilide hydroxamic acid (SAHA), have been shown to act selectively on gene expression, and are potent inducers of growth arrest, differentiation and apoptosis in various types of cancers in vitro and in vivo. This study aimed to elucidate the anti-tumor effects and molecular mechanisms of SAHA on the aggressive phenotypes of ovarian carcinoma. Two pairs of cell lines (SKOV3 and SKOV3/DDP; HO8910 and HO8910-PM) were exposed to SAHA treatment, and the effects on acetyl-Histone H3 and H4 expression levels were analyzed and compared against the aggressive behaviors of ovarian carcinoma. Our results showed that SAHA suppressed proliferation in both a concentration- and time-dependent manner in all four cell lines; induced S/G2 arrest in SKOV3 and SKOV3/DDP cells; and conversely, induced G1 arrest in HO8910 and HO8910-PM cells. SAHA treatment induced apoptosis and reduced migration, invasion and lamellipodia formation in the ovarian carcinoma cells; furthermore, SAHA decreased expression of Cyclin B1 and CDC2P34 mRNA, and downregulated CDC2P34, Erk1/2, CyclinB1 and MMP-9 proteins. In contrast, SAHA increased expression of Caspase-3, p21 and p53 mRNA, and upregulated acetyl-Histones H3 and H4, Caspase-8, and p53 proteins. Basal acetylation of histone H3 and H4 was higher in ovarian carcinoma compared to normal ovarian tissues and benign ovarian tumors, and in borderline tumor than in normal ovarian tissues, and was positively correlated with differentiation and expression of the proliferative marker, Ki-67 (P < 0.05). We suggest that SAHA may suppress growth, migration and invasion in ovarian carcinoma cells, including cisplatin-resistant or highly-invasive ovarian cells, by promoting histone acetylation and modulating their phenotype-related molecules. As such, aberrant acetylation of histone H3 and H4 may play an important role in the carcinogenesis and differentiation of ovarian carcinoma.
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