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Find video protocols related to scientific articles indexed in Pubmed.
[Clinicopathological features associated with EGFR gene mutation in non-small cell lung cancer patients].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 11-18-2014
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To explore the clinicopathological features associated with epidermal growth factor receptor (EGFR) gene mutation in non-small cell lung cancer (NSCLC) patients.
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AgNP-DNA@GQDs Hybrid: A New Approach for Sensitive Detection of H2O2 and Glucose via Simultaneous AgNP Etching and DNA Cleavage.
Anal. Chem.
PUBLISHED: 11-13-2014
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A growing body of evidence suggests that hydrogen peroxide (H2O2) plays an active role in the regulation of various physiological processes. Development of sensitive probes for H2O2 is an urgent work. In this study, we proposed a DNA-mediated silver nanoparticles and graphene quantum dots hybrid nanocomposite (AgNP-DNA@GQDs) for sensitive fluorescent detection of H2O2 and the sensing mechanism is based on the etching effect of H2O2 to AgNP and the cleavage of as-generated hydroxyl radicals (•OH) to DNA. The formation of AgNP-DNA@GQDs nanocomposite results in fluorescence quenching of GQDs by AgNP through the resonance energy transfer. Upon H2O2 addition, the energy transfer between AgNP and GQDs mediated by DNA was weakened and obvious fluorescence recovery of GQDs could be observed. It is worth noting that the reaction product •OH between H2O2 and AgNP could cleave the DNA-bridge and thus enhance the AgNP-DNA@GQDs disassembly to further achieve signal amplification. With optimal condition, the approach achieves lowest limit of detection values of 0.11 ?M. Moreover, this nanocomposite is further extended to the detection of glucose in human urine combining with glucose oxidase (GOx) for the oxidation of glucose and formation of H2O2. The glucose concentrations in human urine are detected with satisfactory recoveries of 94.6-98.8% which holds potential of ultrasensitive quantitative analysis of glucose and supply valuable information for diabetes mellitus research and clinical diagnosis.
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Preeclampsia Does Not Alter Vascular Growth and Expression of CD31 and Vascular Endothelial Cadherin in Human Placentas.
J. Histochem. Cytochem.
PUBLISHED: 11-02-2014
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Preeclampsia is characterized by maternal endothelial dysfunction (e.g., increased maternal vascular permeability caused by the disassembly of endothelial junction proteins). However, it is unclear if preeclampsia is associated with impaired vascular growth and expression of endothelial junction proteins in human placentas. Herein, we examined vascular growth in placentas from women with normal term (NT) and preeclamptic (PE) pregnancies using two endothelial junction proteins as endothelial markers: CD31 and vascular endothelial-cadherin (VE-Cad). We also compared protein and mRNA expression of CD31 and VE-Cad between NT and PE placentas, and determined the alternatively spliced expression of CD31 using PCR. We found that CD31 and VE-Cad were immunolocalized predominantly in villous endothelial cells. However, capillary number density (total capillary number per unit villous area) and capillary area density (total capillary lumen area per unit villous area) as well as CD31 and VE-Cad protein and mRNA levels were similar between NT and PE placentas. PCR in combination with sequence analysis revealed a single, full-length CD31, suggesting that there are no alternatively spliced isoform of CD31 expressed in placentas. These data indicate that preeclampsia does not significantly affect vascular growth or the expression of endothelial junction proteins in human placentas.
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Nephroprotective Effect of Gelsemine Against Cisplatin-Induced Toxicity is Mediated Via Attenuation of Oxidative Stress.
Cell Biochem. Biophys.
PUBLISHED: 10-26-2014
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Cisplatin-induced generation of reactive oxygen species leads to acute nephrotoxicity limiting its use in the treatment of various cancers. Gelsemine, an alkaloid isolated from Gelsemium elegans, is known to possess anti-inflammatory and anti-cancer activities. This study was aimed to investigate as to whether gelsemine can serve as a protective agent against cisplatin-induced nephrotoxicity. Male Wistar rats were divided into 6 groups, each with 6 rats. Group 1 served as control and received the vehicles (peanut oil for 14 days and 0.9 % saline on day 14 for gelsemine and cisplatin respectively). Group 2 received a single intraperitoneal injection of cisplatin on day 14. Group 3 and 4 were pretreated with two different doses of gelsemine in addition to cisplatin, and group 5 and 6 received only gelsemine. The effects of gelsemine on cisplatin-induced nephrotoxicity were examined by measuring anti-oxidant enzymes activities, lipid peroxidation, and DNA damage in the kidneys, a well-established model of oxidative damage. Pretreatment of rats with gelsemine caused a significant attenuation of cisplatin-induced DNA and oxidative damages. The blockade of lipid peroxidation and xanthine oxidase activity was accompanied by increased production and/or activity of anti-oxidants, both enzymatic (catalase, glutathione peroxidase, glutathione reductase, and glutathione-S-transferase) and non-enzymatic (GSH). The biomarkers of kidney malfunctioning, creatinine, and blood urea nitrogen were ameliorated. The results of the present study suggest that gelsemine effectively suppressed cisplatin-induced renal injury by improving redox status.
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2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) inhibits human ovarian cancer cell proliferation.
Cell Oncol (Dordr)
PUBLISHED: 10-20-2014
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The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor, mediates a broad spectrum of biological processes, including ovarian growth and ovulation. Recently, we found that an endogenous AhR ligand (ITE) can inhibit ovarian cancer proliferation and migration via the AhR. Here, we tested whether 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, an exogenous AhR ligand) may exert similar anti-ovarian cancer activities using human ovarian cancer and non-cancerous human ovarian surface epithelial cells.
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Suitable Depth of Epidural Puncture in Nulliparous Pregnant Woman.
Cell Biochem. Biophys.
PUBLISHED: 10-11-2014
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We study the suitable depth for epidural puncture in primiparas so as to decrease epidural complications and provide anesthesiologists with an appropriate insertion guide. A prospective study of 87 primipara patients receiving labor analgesia who had epidural punctures in the course of vaginal delivery were randomly divided into 3 groups: the L 3,4 group (N = 27), the L 2,3 group (N = 29), and the L 1,2 group (N = 26). Predictive statistical models were used for the formulation of the ideal epidural puncture needle depth. Eighty two patients who had non-traumatic epidural punctures were studied. There were no significant changes in age, weight, height, weight/height ratio, gestational weeks, fetus weight, pregnancy weight, weight difference, and fetus weight (P > 0.05). Compared with L 3,4 intervertebral space, the puncture depth in L 1,2 and L 2,3 was significantly shorter (P < 0.05) and (P < 0.001), respectively; Regression equation: PD (cm) = 0.351 [LHZ] + 0.147 [BMI] + 0.017. The correlation coefficient for LHZ was 0.351 (95 % CI 0.278-0.424; P < 0.001), the correlation coefficient for BMI was 0.147 (95 % CI 0.123-0.171; P < 0.001). This formula is accurate and practical with less complex calculations. However, further validation through a prospective study will be required. It is an accurate way to localize the puncture site in parturients and improve the efficiency of puncture in parturients for analgesia labor.Epidural puncture depth prediction in L 1,2, L 2,3, and L 3,4 can supply with a related reference.
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Remote-Controlled Release of DNA in Living Cells via Simultaneous Light and Host-Guest Mediations.
Anal. Chem.
PUBLISHED: 10-06-2014
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Using photons as external triggers to realize remote-controlled release of oligonucleotide is superior to other intracellular or external stimulus. UV light is a valid photon-controlled manner due to high efficiency. However, further applications of these approaches in living cells are hampered by the large dose of UV-light irradiation. To address this issue, a simultaneous light and host/guest mediation was proposed in this paper. Gold nanoparticles (AuNPs) encoding with mercapto-?-cyclodextrin (?CD) served as a carried agent. Azobenzene (Azo), which was labeled on a releasing oligonucleotide, acted as a photochemically controlled switch. Ferrocene (Fc), an excellent guest for inclusion complexation by ?CD, serves as "enhancers" and shifts the equilibrium of the inclusion-exclusion process between trans-Azo and ?CD under UV-light irradiation, thus making the dose of UV-light irradiation reduced obviously. For further application, transfected green fluorescent protein (GFP)-expressing human lung cancer A549 cells were used to determine cellular uptake and gene silencing mediated by our constructed system in vivo. The results demonstrate that by employing Fc host-guest interaction, about 62.4% gene silencing was achieved within 30 min, which is significantly higher than that without Fc competition. Our strategy provides the potential for orthogonal DNA delivery and therapeutic activation that would be capable of achieving higher levels of site-specific activity and reduced amounts of side effects.
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Roles of microRNA in vascular diseases in cardiac and pulmonary systems.
Pharmazie
PUBLISHED: 10-03-2014
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Coronary artery disease (CAD) and pulmonary arterial hypertension (PAH) are two of the most dangerous vascular diseases. Their etiology and pathogenesis are not yet fully understood, thus it remains difficult to achive great advance in the diagnose, therapy and prognosis techniques. microRNAs (miRNAs), a class of highly conserved, small, noncoding RNAs, critically mediate the post-transcriptional gene modulation, which regulates an array of important physiopathological processes including those occurring in cardiac and pulmonary systems. Thereby manipulation of miRNA expression could potentially be applied therapeutically. In this review, we summarize the current knowledge on the roles of miRNAs in the development of vascular diseases, especially in CAD and PAH, providing a theoretical basis for potential uses of miRNA in diagnosis, prognosis, and therapy in these cardiovascular diseases.
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[Rapid screening and confirmation of antidepressants in blood using automated solid phase extraction and liquid chromatography-time-of-flight mass spectrometry].
Se Pu
PUBLISHED: 09-27-2014
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A high-throughput method was developed for screening antidepressants in blood by automated solid phase extraction and liquid chromatography with high resolution quadrupole-time-of-flight mass spectrometry (ASPE-LC-Q-TOF/MS). The samples were cleaned up by an HLB solid phase extraction cartridge and analyzed by LC-Q-TOF/MS under electrospray ionization (ESI) mode with scanning range of m/z 50-1 000 Da. The chromatographic separation was performed on an Agilent Eclipse Plus C18 column (50 mm x 2.1 mm, 1.8 microm) with gradient elution using methanol and 5 mmol/L ammonium formate aqueous solution (containing 0.2% formic acid) as mobile phases. Rapid screening and confirmation can be achieved using MS matching scores, deviation of retention time, measured mass, isotopic abundance matching scores, isotope space matching scores and MS/MS matching scores. The quantitative analysis was carried out by correlating the extracting peak area with accurate mass. Good linearities were observed in the range of 1 - 500 microg/L with the correlation coefficients from 0.997 6 to 0.999 7. The limits of detection were 0.01-0.5 microg/L. The spiked recoveries were 79.6%-96.4% with the relative standard deviations of 4.1% - 6.4%. The result screening database was built using Agilent MassHunter PCDL Manager software and then used for the analysis of spiked samples. MS matching scores, isotopic abundance matching scores, isotope space matching scores (all > 95 points) and MS/MS matching scores (> 70 points) were applied to identify the analytes. The results showed that all the spiked antidepressants could be correctly identified with low deviation of retention time (< 0.1 min) and mass (< 1 mDa). The developed method was further applied for the analysis of poisoning cases, and amitriptyline, carbamazepine, doxepin were detected. In brief, the method is rapid, sensitive, simple, reliable, and suitable for the screening and confirmation of antidepressants in forensic and clinical analytical toxicology.
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The impact of clickers instruction on cognitive loads and listening and speaking skills in college English class.
PLoS ONE
PUBLISHED: 09-05-2014
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Clickers might own a bright future in China if properly introduced although they have not been widely acknowledged as an effective tool to facilitate English learning and teaching in Chinese contexts. By randomly selecting participants from undergraduates in a university in China over four academic years, this study aims to identify the impact of clickers on college English listening and speaking skills, and differences in cognitive loads between clickers and traditional multimedia assisted instruction modes. It was concluded that in China's college English class, compared with multimedia assisted instruction, (1) clickers could improve college English listening skills; (2) clickers could improve college English speaking skills; and (3) clickers could reduce undergraduates' cognitive loads in College English Class. Reasons for the results and defects in this study were also explored and discussed, based on learning, teaching and cognitive load theories. Some Suggestions for future research were also raised.
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[Effects of prednisone on renal FAK and Pyk2 expressions in rats with adriamycin- induced nephritis].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 09-02-2014
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To investigate the effects of prednisone on the expressions of FAK and Pyk2 in the kidneys of rats with adriamycin-induced nephritis.
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High-temperature inhibition of biosynthesis and transportation of anthocyanins results in the poor red coloration in red-fleshed Actinidia chinensis.
Physiol Plant
PUBLISHED: 08-21-2014
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In plants, the role of anthocyanins trafficking in response to high temperature has been rarely studied, and therefore poorly understood. Red-fleshed kiwifruit has stimulated the world kiwifruit industry owing to its appealing color. However, fruit in warmer climates have been found to have poor flesh coloration, and the factors responsible for this response remain elusive. Partial correlation and regression analysis confirmed that accumulative temperatures above 25°C (T25) was one of the dominant factors inhibiting anthocyanin accumulation in red-fleshed Actinidia chinensis, 'Hongyang'. Expression of structural genes, AcMRP and AcMYB1 in inner pericarp sampled from the two high altitudes (low temperature area), was notably higher than the low altitude (high temperature area) during fruit coloration. AcMYB1 and structural genes coordinate expression supported the MYB-bHLH (basic helix-loop-helix)-WD40 regulatory complex mediated downregulation of anthocyanin biosynthesis induced by high temperatures in kiwifruit. Moreover, cytological observations using the light and transmission electronic microscopy showed that there were a series of anthocyanic vacuolar inclusion (AVI)-like structures involved in their vacuolization process and dissolution of the pigmented bodies inside cells of fruit inner pericarp. Anthocyanin transport was inhibited by high temperature via retardation of vacuolization or reduction in AIV-like structure formation. Our findings strongly suggested that complex multimechanisms influenced the effects of high temperature on red-fleshed kiwifruit coloration.
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Emodin enhances ATRA-induced differentiation and induces apoptosis in acute myeloid leukemia cells.
Int. J. Oncol.
PUBLISHED: 08-19-2014
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Emodin, an extracted natural compound from the root and rhizome of Rheum palmatum L, has been shown to have multiple biological activities including anticancer functions in previous studies. In this study, we investigated the anti-leukemic activity of emodin alone or emodin in the presence all-trans retinoic acid (ATRA) in acute myeloid leukemia (AML) cells and the potential signaling pathway involved. We demonstrated that emodin could significantly enhance the sensitivity to ATRA and present additive differentiation-inducing effects in AML cell line NB4 cells and, especially, in NB4-derived ATRA-resistant MR2 cells. Further study showed that increasing dose of emodin could effectively induce growth inhibition and apoptotic effects in both cell lines as well as in primary leukemic cells from AML patients. Moreover, the apoptotic induction in AML cells was associated with the activation of caspase cascades involving caspase-9, caspase-3, and poly(ADP-ribose) polymerase (PARP) cleavage. In addition, leukemic cell response to emodin stimuli in vitro was observed through the decreased expression levels of Bcl-2 and retinoic acid receptor ? (RAR?). Importantly, emodin was demonstrated as a new inhibitor of PI3K/Akt in AML cells, even in primary AML cells. It inhibited Akt phosphoration (p-Akt) at Ser473 as efficiently as mTOR at Ser2448. Consistently, it exerted suppression effects on the phosphoration of mTOR downstream targets, 4E-BP1 and p70S6K. Taken together, these findings indicate that emodin might be developed as a promising anti-leukemic agent to improve the patient outcome in AML.
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Competitive assembly to increase the performance of the DNA/carbon-nanomaterial-based sensing platform.
ACS Appl Mater Interfaces
PUBLISHED: 08-06-2014
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Increasing the rate of target binding on the surface and enhancing the fluorescence signal restoration efficiency are critical to the desirable biomedical application of carbon nanomaterials, for example, single-walled carbon nanotubes (SWNTs). We describe here a strategy to increase the target binding rate and enhance the fluorescence signal restoration efficiency on the DNA-functionalized SWNT surface using a short complementary DNA (scDNA) strand. The scDNA causes up to a 2.5-fold increase in association rate and 4-fold increase in fluorescence signal restoration by its competitive assembly on the nanostructure's surface and inducing a conformational change that extends the DNA away from the surface, making it more available to bind target nucleic acids. The scDNA-induced enhancement of binding kinetics and fluorescence signal restoration efficiency is a general phenomenon that occurred with all sequences and surfaces investigated. Through this competitive assembly strategy of scDNA, performance improvement of the carbon-nanomaterial-based biosensing platform for both in vitro detection and live cell imaging can be reached.
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Loss of the tectorial membrane protein CEACAM16 enhances spontaneous, stimulus-frequency, and transiently evoked otoacoustic emissions.
J. Neurosci.
PUBLISHED: 08-01-2014
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?-Tectorin (TECTA), ?-tectorin (TECTB), and carcinoembryonic antigen-related cell adhesion molecule 16 (CEACAM) are secreted glycoproteins that are present in the tectorial membrane (TM), an extracellular structure overlying the hearing organ of the inner ear, the organ of Corti. Previous studies have shown that TECTA and TECTB are both required for formation of the striated-sheet matrix within which collagen fibrils of the TM are imbedded and that CEACAM16 interacts with TECTA. To learn more about the structural and functional significance of CEACAM16, we created a Ceacam16-null mutant mouse. In the absence of CEACAM16, TECTB levels are reduced, a clearly defined striated-sheet matrix does not develop, and Hensen's stripe, a prominent feature in the basal two-thirds of the TM in WT mice, is absent. CEACAM16 is also shown to interact with TECTB, indicating that it may stabilize interactions between TECTA and TECTB. Although brain-stem evoked responses and distortion product otoacoustic emissions are, for most frequencies, normal in young mice lacking CEACAM16, stimulus-frequency and transiently evoked emissions are larger. We also observed spontaneous otoacoustic emissions (SOAEs) in 70% of the homozygous mice. This incidence is remarkable considering that <3% of WT controls have SOAEs. The predominance of SOAEs >15 kHz correlates with the loss of Hensen's stripe. Results from mice lacking CEACAM16 are consistent with the idea that the organ of Corti evolved to maximize the gain of the cochlear amplifier while preventing large oscillations. Changes in TM structure appear to influence the balance between energy generation and dissipation such that the system becomes unstable.
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Rh(III)-catalyzed C-H activation/cyclization of indoles and pyrroles: divergent synthesis of heterocycles.
J. Org. Chem.
PUBLISHED: 06-26-2014
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We report herein a new strategy of the Rh(III)-catalyzed C-H activation/cyclization of indoles and pyrroles, for the divergent synthesis of privileged heterocycles. A simple derivation of indoles and pyrroles to N-carboxamides with oxidative bidentate directing group could enable rhodacycle formation and late-stage redox-neutral cyclization with alkynes, alkenes and diazo compounds, for access to five- and six-membered fused heterocycles, such as pyrimido[1,6-a]indol-1(2H)-one, 3,4-dihydropyrimido[1,6-a]indol-1(2H)-one, and 1H-imidazo[1,5-a]indol-3(2H)-ones. Kinetic isotope effect study was conducted, and a plausible mechanism was proposed. Furthermore, this protocol was applied to concise synthesis of 5-HT3 receptor antagonist in gram-scale.
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Rh(III)-catalyzed selective coupling of N-methoxy-1H-indole-1-carboxamides and aryl boronic acids.
Org. Lett.
PUBLISHED: 06-24-2014
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A Rh(III)-catalyzed selective coupling of N-methoxy-1H-indole-1-carboxamide and aryl boronic acids is reported. The coupling is mild and efficient toward diverse product formation, with selective C-C and C-C/C-N bond formation. Kinetic isotope effects studies were conducted to reveal a mechanism of C-H activation and electrophilic addition.
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Preparation of a magnetic metal organic framework composite and its application for the detection of methyl parathion.
Anal Sci
PUBLISHED: 06-13-2014
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A magnetic metal organic framework (MOF) composite was prepared. The composite was fabricated by incorporation of Fe3O4 nanoparticals with MOF. It was characterized and expected to offer a promising template for molecular immobilization and sensor fabrication because of its ordered structure and satisfying large specific surface area. The resulting composite was used to detect methyl parathion. Electrochemical measurements showed that the multifunctional composite of MOF provided an excellent matrix for the co-adsorption of methyl parathion. Owing to the ordered structure, the large surface area, excellent compatibility and magnetic property of the material, methyl parathion could be separated, accumulated and directly detected in the solution with high sensitivity. The differential pulse voltammetry (DPV) response was proportional to the concentration range from 5.00 × 10(-6) to 5.00 × 10(-3) g L(-1) with the detection limit of 3.02 × 10(-6) g L(-1). The experimental results can lead to a widespread use of electrochemical sensors to detect organophosphorous pesticides contaminates and other substances.
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Dual-stimuli responsive i-motif/nanoflares for sensing ATP in lysosomes.
Analyst
PUBLISHED: 06-07-2014
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A dual-stimuli responsive i-motif/nanoflare for molecule detection in lysosomes was designed. By combining the structure-switchable i-motif sequence and high recognition ability of an adenosine triphosphate (ATP) aptamer, subcellular sensing and visualization sensing of ATP in lysosomes at the subcellular level can be achieved. This general sensing technique can be applied for a broad range of cellular communication studies to improve our understanding of subcellular signaling and function.
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Direct asymmetric aldol reactions catalyzed by lipase from porcine pancreas.
Z. Naturforsch., C, J. Biosci.
PUBLISHED: 05-31-2014
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Porcine pancreas lipase type II (PPL II) exhibited unnatural catalytic activity in direct asymmetric aldol reactions between cyclic ketones and aromatic or heteroaromatic aldehydes in acetonitrile in the presence of phosphate buffer. A wide range of substrates was accepted by the enzyme to afford the corresponding aldol products in low to high yields (10-98%), with moderate to excellent enantioselectivities (53-94% ee, for anti-isomers) and low to moderate diastereoselectivities (48/52-87/13 dr, anti/syn). This methodology expands the application of PPL II, and it might be developed into a potentially valuable method for sustainable organic synthesis.
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Protein tyrosine phosphatase receptor U (PTPRU) is required for glioma growth and motility.
Carcinogenesis
PUBLISHED: 05-29-2014
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The membrane protein tyrosine phosphatase receptor U (PTPRU) has been shown to function as a negative regulator of adhesion and proliferation in certain cancer cell types, primarily through its dephosphorylation of ?-catenin and inhibition of subsequent downstream signaling. In the present study, we set out to characterize the role of PTPRU in glioma and found that, while the expression of full-length PTPRU protein is low in these tumors, a number of non-full-length PTPRU isoforms are highly expressed. Among these isoforms, one in particular is localized to the nucleus, and its expression is increased in glioma tissues in a manner that positively correlates with malignancy grade. Short hairpin RNA knockdown of endogenous PTPRU in human and rat glioma cell lines suppressed proliferation, survival, invasion, migration, adhesion and vasculogenic tube formation in vitro, as well as intracranial tumor progression in vivo. In addition, knocking down PTPRU reduced tyrosine phosphorylation (pY) and transcriptional activity of ?-catenin, and we were able to specifically rescue the cell migration defect by expressing a LEF1-?-catenin fusion protein in PTPRU-depleted cells. PTPRU knockdown also led to increased tyrosine pY of the E3 ubiquitin ligase c-Cbl and to the destabilization of several focal adhesion proteins. Taken together, our findings demonstrate that endogenous PTPRU promote glioma progression through their effect on ?-catenin and focal adhesion signaling.
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A three-dimensional zinc-based coordination polymer built from 5-carboxylato-1-carboxylatomethyl-2-oxidopyridinium with a 4-connected sra topology.
Acta Crystallogr C Struct Chem
PUBLISHED: 05-12-2014
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A novel three-dimensional Zn(II) complex, poly[aqua(?4-5-carboxylato-1-carboxylatomethyl-2-oxidopyridinium)zinc(II)], [Zn(C8H5NO4)(H2O)]n, has been prepared by hydrothermal assembly of Zn(CH3COO)2·2H2O and 5-carboxy-1-(carboxymethyl)pyridin-1-ium-2-olate (H2ccop). The ccop(2-) anions bridge the Zn(II) cations in a head-to-tail fashion via monodentate aromatic carboxylate and phenolate O atoms to form an extended zigzag chain which runs parallel to the [011] direction. One O atom of the aliphatic carboxylate group of the ccop(2-) ligand coordinates to the Zn(II) atom of a neighbouring chain thereby producing undulating layers which lie parallel to the (01-1) plane. A similar parallel undulating planar structure can be obtained if a path involving the other O atom of the aliphatic carboxylate group is considered. Thus, the aliphatic carboxylate group acts in a bridging bidentate mode to give extended -Zn-O-C-O-Zn- sequences running parallel to [001] which link the layers into an overall three-dimensional framework. The three-dimensional framework can be simplified as a 4-connected sra topology with a Schläfli symbol of 4(2).6(3).8 if all the Zn(II) centres and ccop(2-) anions are regarded as tetrahedral 4-connected nodes. The three-dimensional luminescence spectrum was measured at room temperature with excitation and emission wavelengths of 344-354 and 360-630?nm, respectively, at intervals of 0.15 and 2?nm, respectively.
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Regulatory effects of resveratrol on glucose metabolism and T-lymphocyte subsets in the development of high-fat diet-induced obesity in C57BL/6 mice.
Food Funct
PUBLISHED: 05-10-2014
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High-fat diet (HFD)-induced obesity is often associated with immune dysfunction. Resveratrol (trans-3,5,4'-trihydroxystilbene), which has well-founded immunity-related beneficial properties, was used to elucidate the regulatory effect on glucose metabolism and T-lymphocyte subsets in the development of HFD-induced obesity. Resveratrol, being associated with decreases of plasma leptin and plasma lipids and the release of oxidative stress, significantly decreased the body weight and fat masses in HF mice after 26 weeks of feeding. Furthermore, resveratrol decreased the fasting blood glucose and fasting plasma insulin and increased the CD3(+)CD4(+)/CD3(+)CD8(+) subsets percentages and the regulatory T cells (Tregs) production after 13 and 26 weeks of feeding. The results indicate that resveratrol, as an effective supplement for HFD, maintained glucose homeostasis by activating the PI3K and SIRT1 signaling pathways. Moreover, resveratrol activated the Nrf2 signaling pathway-mediated antioxidant enzyme expression to alleviate inflammation by protecting against oxidative damage and T-lymphocyte subset-related chronic inflammatory response in the development of HFD-induced obesity.
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Inhibition of 32Dp210 cells harboring T315I mutation by a novel derivative of emodin correlates with down-regulation of BCR-ABL and its downstream signaling pathways.
J. Cancer Res. Clin. Oncol.
PUBLISHED: 05-08-2014
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The clinical outcome of chronic myeloid leukemia (CML) patients has been changed dramatically due to the development of imatinib (IM). However, the emergence of IM resistance, commonly associated with point mutations within the BCR-ABL kinase domain, remains a major clinical problem. Here, we investigated the effects of E35, a novel derivative of emodin, on the IM-resistant 32Dp210-T315I cells.
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S-nitrosylation of Cofilin-1 Serves as a Novel Pathway for VEGF-stimulated Endothelial Cell Migration.
J. Cell. Physiol.
PUBLISHED: 04-11-2014
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Nitric oxide (NO) derived from endothelial NO synthase (eNOS) mediates vascular endothelial growth factor (VEGF)-stimulated endothelial cytoskeleton remodeling and migration; however, the underlying mechanisms are elusive. Covalent adduction of a NO moiety (NO(•) ) to cysteines called S-nitrosylation (SNO) is a key NO signaling pathway. The small actin-binding protein cofilin-1 (CFL1) is essential for actin cytoskeleton remodeling. We investigated whether S-nitrosylation regulates CFL1 function and endothelial cytoskeleton remodeling and migration upon VEGF stimulation. VEGF rapidly stimulated S-nitrosylation of CFL1, which was blocked by NO Synthase inhibition and eNOS knockdown by specific eNOS-siRNA. Cys80 and Cys139 were identified as the major SNO-sites in CFL1 by LC-MS/MS. The actin severing activity of recombinant SNO-mimetic CFL1 (C80/139A DMA-CFL1), but not SNO-deficient CFL1 (C80/139S DMS-CFL1), was significantly greater than that of wild-type CFL1 (wt-CFL1). When wt-CFL1 and its mutants were overexpressed in endothelial cells, basal actin bound wt-CFL1 was undetectable but significantly increased by VEGF; basal actin bound DMA-CFL1 was readily high and basal actin bound DMS-CFL1 was detectable but low, and both were unresponsive to VEGF. Treatment with VEGF significantly increased filamentous (F-) actin and filopodium formation and cell migration in endothelial cells. Overexpression of wt-CFL1 inhibited VEGF-induced F-actin formation. Overexpression of DMA but not DMS CFL1 decreased basal but not VEGF-stimulated F-actin formation. Overexpression of DMA but not DMS CFL1 suppressed VEGF-stimulated filopodium formation and migration in endothelial cells. Thus, S-nitrosylation of CFL1 provides a novel signaling pathway post-NO biosynthesis via eNOS-derived NO for endothelial cytoskeleton remodeling and migration upon VEGF stimulation. J. Cell. Biochem. © 2014 Wiley Periodicals, Inc.
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Elevated levels of polychlorinated biphenyls in plants, air, and soils at an E-waste site in Southern China and enantioselective biotransformation of chiral PCBs in plants.
Environ. Sci. Technol.
PUBLISHED: 03-21-2014
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E-waste that contains polychlorinated biphenyls (PCBs) is moved across national boundaries, often from industrialized countries in the northern hemisphere, where the items were formerly used, to subtropical and tropical regions in southeastern Asia and Africa. As a result, there is a high likelihood that PCBs will be released into the environment from a primary source due to the elevated temperatures encountered in these low-latitude regions. In the present study, PCBs and enantiomer fractions (EFs) of chiral PCBs (PCB 84, 95, 132, 136, 149, and 183) were analyzed in air, eucalyptus leaves, pine needles, and soil at an e-waste site and a rural site in southern China. The concentrations of PCBs at the e-waste site ranged from 7825 to 76330 pg/m(3), 27.5 to 1993 ng/g, and 24.2 to 12045 ng/g in the air (gas plus particle), plant leaves, and soils, respectively. The atmospheric PCB composition profiles in the present study indicated relatively high abundances of penta- and hexa-PCBs, which were different from those previously observed in the air across China. The Clausius-Clapeyron regression analysis indicated that evaporation from local contaminated surfaces constitutes a primary emission source of PCBs in the air at the e-waste site. The chiral signatures of PCBs in the air at the e-waste site were essentially racemic (mean EFs = (0.484 ± 0.022)-(0.499 ± 0.004) in the gaseous phase) except for PCB 84 (0.420 ± 0.050), indicating that racemic sources dominate the PCB emission in the air. PCB chiral signatures in the soils ((0.422 ± 0.038)-(0.515 ± 0.016)) were similar to those in the air except for PCB 95. However, the chiral PCBs in the plants (especially the eucalyptus leaves) had significantly nonracemic residues ((0.368 ± 0.075)-(0.561 ± 0.045)) compared to those in the air and soil. This finding suggests that enantioselective biotransformation of these atropisomeric PCBs was very likely to occur in the plant leaves, possibly due to metabolism by cytochrome P-450 enzymes in leaves. To our knowledge, this is the first report on the enantioselective metabolism of chiral PCBs in plants under field conditions.
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Distinct roles of HIF1A in endothelial adaptations to physiological and ambient oxygen.
Mol. Cell. Endocrinol.
PUBLISHED: 03-11-2014
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Fetoplacental endothelial cells reside under physiological normoxic conditions (?2-8% O2) in vivo. Under such conditions, cells are believed to sense O2 changes primarily via hypoxia inducible factor 1 ? (HIF1A). However, little is known regarding the role of HIF1A in fetoplacental endothelial function under physiological normoxia. We recently reported that physiological chronic normoxia (PCN; 20-25 day, 3% O2) enhanced FGF2- and VEGFA-stimulated proliferation and migration of human umbilical vein endothelial cells (HUVECs) via the MEK/ERK1/2 and PI3K/AKT1 pathways compared to standard cell culture normoxia (SCN; ambient O2: ?21% O2). Here, we investigated the action of HIF1A in regulating these cellular responses in HUVECs. HIF1A adenovirus infection in SCN-cells increased HIF1A protein expression, enhanced FGF2- and VEGFA-stimulated cell proliferation by 2.4 and 2.0-fold respectively, and promoted VEGFA-stimulated cell migration by 1.4-fold. HIF1A adenovirus infection in SCN-cells did not affect either basal or FGF2- and VEGFA-induced ERK1/2 activation, but it decreased basal AKT1 phosphorylation. Interestingly, HIF1A knockdown in PCN-cells via specific HIF1A siRNA transfection did not alter FGF2- and VEGFA-stimulated cell proliferation and migration, or ERK1/2 activation; however, it inhibited FGF2-induced AKT1 activation by ?50%. These data indicate that HIF1A differentially regulates cell proliferation and migration, and ERK1/2 and AKT1 activation in PCN- and SCN-HUVECs. These data also suggest that HIF1A critically regulates cell proliferation and migration in SCN-, but not in PCN-HUVECs.
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Recombinant influenza H1, H5 and H9 hemagglutinins containing replaced H3 hemagglutinin transmembrane domain showed enhanced heterosubtypic protection in mice.
Vaccine
PUBLISHED: 02-24-2014
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Influenza A viruses cause annual epidemics and irregular pandemics. A vaccine with heterosubtypic protection (hetero-protection) has been needed. In the present study, various influenza H1, H3, H5, and H9 hemagglutinin (HA) proteins were expressed in insect cells, and then mice were subcutaneously immunized with the expressed HA proteins, and challenged by influenza A viruses (A/Puerto Rico/8/1934 (H1N1) or A/chicken/Guangdong/96 (H9N2)). The results first showed that wild-type H3 hemagglutinin (HA) (H3-WT), but not a transmembrane domain (TM) mutant, had hetero-protection against both H1N1 and H9N2 with survival rates of 17% and 33% respectively, and that wild-type H1 (H1-WT), H5 (H5-WT) and H9 (H9-WT) had no hetero-protection against H1N1 or H9N2 except for H5-WT against H1N1 with a survival rate of 17%. Then the H3-WT TM replaced the TMs of H1-WT, H5-WT and H9-WT to generate recombinant H1-TM, H5-TM and H9-TM respectively, and whether the H3-WT TM-dependent hetero-protection could be transferred to these TM mutants was investigated. The results showed that the H3-WT TM-dependent hetero-protection was transferable. H1-TM against H9N2 and H9-TM against H1N1 were with survival rates of 33% and 17% respectively, and H5-TM against both H1N1 and H9N2 with survival rates of 50% and 17% respectively. Furthermore, higher dosage H5-TM scored 100% hetero-protection against H1N1. These results demonstrated that replacement of the TMs of non-H3 HAs with H3-WT TM could enhance their hetero-protection. These findings would help the development of future influenza vaccines against pandemics such as the recently appeared H7N9 infection.
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Synthesis and spectroscopic properties of some new difluoroboron bis-?-diketonate derivatives.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 02-19-2014
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Six new bis-?-diketones (RCOCH2CO-C7H7N-COCH2COR) were synthesized from 3,5-diacetyl-2,6-dimethylpyridine via Claisen condensation with the corresponding esters, and then reacted with boron trifluoride etherate to afford difluoroboron bis-?-diketonate derivatives. Their spectroscopic properties were investigated by UV-vis, FTIR, (1)H NMR and fluorescence spectroscopic techniques. It was found that these boron complexes exhibited violet or blue fluorescence emission at 422-445nm and possessed high extinction coefficients. The results indicate that the extending ?-conjugation can increase the fluorescence intensity and quantum yield for these boron complexes. Especially, the compound 2b displayed the stronger fluorescence intensity and the highest fluorescence quantum yield (?u=0.94) in these boron compounds. However, compounds 2c and 2d had the lower fluorescence intensity and quantum yield as a result of the heavy atom effect of the chlorine atom in the molecules.
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Occurrence of brominated flame retardants (BFRs), organochlorine pesticides (OCPs), and polychlorinated biphenyls (PCBs) in agricultural soils in a BFR-manufacturing region of North China.
Sci. Total Environ.
PUBLISHED: 02-06-2014
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We investigated the occurrence of brominated flame retardants (BFRs), organochlorine pesticides (OCPs), and polychlorinated biphenyls (PCBs) in the surface soils from the largest BFR-manufacturing and vegetable farming center (Shouguang) of North China. The total concentrations of BFRs ranged from 39.9 to 8,145 ng/g dry weight with a mean of 1,947 ng/g. The BFRs were dominated by decabromodiphenylethane (deca-BDEs) and tetrabromobisphenol A (TBBPA), with means of 1127 and 672 ng/g, respectively, followed by decabromodiphenyl ethane (DBDPE) (111 ng/g) and hexabromocyclododecanes (HBCD) (37.5 ng/g). This profile was generally consistent with the BFR production and use in China, except for TBBPA. Although the lower brominated BDEs (tri- through hepta-BDEs) in the soil may originate from technical deca-BDE mixtures as trace impurities and/or from the degradation of deca-BDEs, deca-BDE was shown to be persistent in the soil. The concentrations of OCPs (44 ng/g) were significantly lower than those of BFRs and displayed a spatial distribution opposite to that of BFRs, which was concentrated in the industrial zone. PCBs (with the lowest levels) showed a relatively uniform spatial distribution because of regional diffusive sources. The mass inventories for the entire land soil (20-cm) were estimated to be 1042, 26, and 3.7 t for BFRs, OCPs, and PCBs, respectively.
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One-step calcination-free synthesis of multicomponent spinel assembled microspheres for high-performance anodes of li-ion batteries: a case study of MnCo(2)O(4).
ACS Appl Mater Interfaces
PUBLISHED: 02-06-2014
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Multicomponent spinel metal-oxide assembled mesoporous microspheres, promising anode materials for Li-ion batteries with superior electrochemical performance, are usually obtained using different kinds of precursors followed by high-temperature post-treatments. Nevertheless, high-temperature calcinations often cause primary particles to aggregate and coarsen, which may damage the assembled microsphere architectures, leading to deterioration of electrochemical performance. In this work, binary spinel metal-oxide assembled mesoporous microspheres MnCo2O4 were fabricated by one-step low-temperature solvothermal method through handily utilizing the redox reaction of nitrate and ethanol. This preparation method is calcination-free, and the resulting MnCo2O4 microspheres were surprisingly assembled by nanoparticles and nanosheets. Two kinds of MnCo2O4 crystal nucleus with different exposed facet of (1?10) and (11?2?) could be responsible for the formation of particle-assembled and sheet-assembled microspheres, respectively. Profiting from the self-assembly structure with mesoporous features, MnCo2O4 microspheres delivered a high reversible capacity up to 722 mAh/g after 25 cycles at a current density of 200 mA/g and capacities up to 553 and 320 mAh/g after 200 cycles at a higher current density of 400 and 900 mA/g, respectively. Even at an extremely high current density of 2700 mA/g, the electrode still delivered a capacity of 403 mAh/g after cycling with the stepwise increase of current densities. The preparation method reported herein may provide hints for obtaining various advanced multicomponent spinel metal-oxide assembled microspheres such as CoMn2O4, ZnMn2O4, ZnCo2O4, and so on, for high-performance energy storage and conversion devices.
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[Over-expressed microRNA-7 inhibits the growth of human lung cancer cells via suppressing CGGBP1 expression].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 02-05-2014
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To investigate the effect of microRNA-7 (miR-7) over-expression on the growth of human lung cancer cells in vivo and in vitro and explore its possible mechanism.
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Essential role of program death 1-ligand 1 in regulatory T-cell-afforded protection against blood-brain barrier damage after stroke.
Stroke
PUBLISHED: 02-04-2014
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Our recent research revealed that adoptively transferred regulatory T cells (Tregs) reduced acute ischemic brain injury by inhibiting neutrophil-derived matrix metalloproteinase-9 (MMP-9) and protecting against blood-brain barrier damage. The mechanisms underlying Treg interactions with neutrophils remain elusive. This study evaluates the contribution of program death 1-ligand 1 (PD-L1) to Treg-mediated neutrophil inhibition and neuroprotection after cerebral ischemia.
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Universal surface-enhanced Raman scattering amplification detector for ultrasensitive detection of multiple target analytes.
Anal. Chem.
PUBLISHED: 01-30-2014
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Up to now, the successful fabrication of efficient hot-spot substrates for surface-enhanced Raman scattering (SERS) remains an unsolved problem. To address this issue, we describe herein a universal aptamer-based SERS biodetection approach that uses a single-stranded DNA as a universal trigger (UT) to induce SERS-active hot-spot formation, allowing, in turn, detection of a broad range of targets. More specifically, interaction between the aptamer probe and its target perturbs a triple-helix aptamer/UT structure in a manner that activates a hybridization chain reaction (HCR) among three short DNA building blocks that self-assemble into a long DNA polymer. The SERS-active hot-spots are formed by conjugating 4-aminobenzenethiol (4-ABT)-encoded gold nanoparticles with the DNA polymer through a specific Au-S bond. As proof-of-principle, we used this approach to quantify multiple target analytes, including thrombin, adenosine, and CEM cancer cells, achieving lowest limit of detection values of 18 pM, 1.5 nM, and 10 cells/mL, respectively. As a universal SERS detector, this prototype can be applied to many other target analytes through the use of suitable DNA-functional partners, thus inspiring new designs and applications of SERS for bioanalysis.
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Functional regulation of the SLC26-family protein prestin by calcium/calmodulin.
J. Neurosci.
PUBLISHED: 01-24-2014
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The solute carrier gene family 26 (SLC26) encodes membrane proteins with diverse physiological roles but with the common feature of halide involvement. Here, we present bioinformatic and biochemical evidence that SLC26 proteins have intrinsically disordered regions (IDRs) in their C-terminal domains and that these regions contain calmodulin (CaM) binding sites. The veracity of these predictions and the functional consequences of CaM binding were examined in prestin, SLC26A5, as a model for the SLC26 family and as one of the most investigated and best understood members. We found that CaM binds directly to the IDR in the C-terminal domain of prestin in a calcium-obligate manner. Using both isolated murine outer hair cells (OHCs) and a heterologous expression system, we also found that this calcium-obligate CaM binding shifts the operating point of the protein to more hyperpolarized potentials with consequent alteration of the function of the prestin. Because calcium is the main intracellular second messenger used by the efferent medial olivocochlear (MOC) pathway of the auditory system and CaM is abundant in OHCs, the CaM-prestin interaction may be involved in the MOC-mediated modulation of cochlear amplification. However, this regulatory mechanism is not likely to be restricted to cochlear OHCs, in light of both clear bioinformatic evidence and the fact that calcium and CaM are ubiquitous intracellular second messengers used by virtually all cell types. Hence, the calcium/CaM-dependent regulatory mechanism described herein is likely applicable to most, if not all, SLC26 paralogs.
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Baicalin attenuates transforming growth factor-?1-induced human pulmonary artery smooth muscle cell proliferation and phenotypic switch by inhibiting hypoxia inducible factor-1? and aryl hydrocarbon receptor expression.
J. Pharm. Pharmacol.
PUBLISHED: 01-23-2014
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Baicalin, a natural flavone, has antithrombotic, antihyperlipidemic and antiinflammortory activity. It can also inhibit cancer cell proliferation and reduce brain cell apoptosis. This study aimed to elucidate the effect of baicalin on the excessive proliferation of human pulmonary arterial smooth muscle cells (HPASMCs) induced by transforming growth factor-?1 (TGF-?1) and to investigate the roles of hypoxia inducible factor-1? (HIF-1?) and aryl hydrocarbon receptor (AhR) in mediating this TGF-?1-induced excessive proliferation of HPASMCs.
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Determination of amitraz and its metabolites in whole blood using solid-phase extraction and liquid chromatography-tandem mass spectrometry.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 01-20-2014
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A method was developed for determination of amitraz and its metabolites, N-[2,4-(dimethylphenyl)-N'-methylformamidine (DMPF), 2,4-dimethylformamidine (DMF), 2,4-dimethylaniline (DMA) in whole blood. The analytes were extracted by solid-phase extraction (SPE) using dichloromethane, acetonitrile and methanol (2:1:1) mixture as elute solution. Analysis was performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in the positive ion mode using multiple reaction monitoring (MRM) technique. Collision-induced dissociation (CID) of amitraz at the electrospray source in MS/MS was observed in the analytic conditions. The method was validated in human whole blood spiked at three concentration levels. The low limit of detection (LOD) and the low limit of quantification (LOQ) for all the analytes were below 0.5?g/L and 2?g/L, respectively. Recoveries were between 90.2% and 104.5%, Bias and relative standard deviation (RSD) were below 15% (n=6). The good linear relationships were obtained in certain concentration ranges of amitraz and its metabolites. The results demonstrated the method is exclusive, sensitive and accurate, and can be applied in forensic toxicology.
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The relationship between patient safety culture and adverse events: a questionnaire survey.
Int J Nurs Stud
PUBLISHED: 01-15-2014
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Patient safety culture is an important factor in the effort to reduce adverse events in the hospital and improve patient safety. A few studies have shown the relationship between patient safety culture and adverse events, yet no such research has been reported in China.
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Expression of G-protein subunit ?-14 is increased in human placentas from preeclamptic pregnancies.
J. Histochem. Cytochem.
PUBLISHED: 01-14-2014
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G-proteins mediate cellular function upon interaction with G-protein coupled receptors. Of the 16 mammalian G-protein ? subunits identified, G-protein subunit ?-11 (GNA11) and -14 (GNA14) have been implicated in modulating hypertension and endothelial function. However, little is known about their expression and roles in human placentas. Here, we examined GNA11 and GNA14 protein expression in first trimester (FT), normal term (NT), and severe preeclamptic (sPE) human placentas as well as in NT human umbilical cords. We found that GNA11 and GNA14 were immunolocalized primarily in trophoblasts, villous stromal cells, and endothelial cells in placentas as well as in endothelial and/or smooth muscle cells of the umbilical cord artery and vein. Western blotting revealed that the GNA14, but not GNA11, protein levels were increased (2.5-2.9 fold; p<0.01) in sPE vs. NT placentas. GNA11 protein was detected only in NT, but not FT, placentas, whereas GNA14 protein levels were increased (7.7-10.6 fold; p<0.01) in NT vs. FT placentas. Thus, GNA11 and GNA14 may mediate the function of several cell types in placentas. Moreover, the high expression of GNA14 in sPE placentas may also imply its importance in sPE pregnancies as in the other hypertension-related disorders.
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Purification and characterization of antimicrobial peptides from fish isolate Carnobacterium maltaromaticum C2: Carnobacteriocin X and carnolysins A1 and A2.
Int. J. Food Microbiol.
PUBLISHED: 01-14-2014
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Carnobacterium maltaromaticum C2, isolated from Brazilian smoked fish (Surubim, Pseudoplatystoma sp.), was found to exert antimicrobial activity against Listeria monocytogenes, an important foodborne pathogen. In this study, the bacteriocins produced by C. maltaromaticum C2 were purified via an extraction with XAD-16 resin, a C18 solid phase extraction, followed by reversed-phase fast protein liquid chromatography. The purified active fractions were characterized using tandem mass spectrometry, permitting the identification of multiple bacteriocins. Carnobacteriocins BM1, B1, and a variant of carnobacteriocin B2 were all found, providing much of the antilisterial activity. Additionally, we herein report the first isolation of the previously predicted antimicrobial peptide carnobacteriocin X. Moreover, C. maltaromaticum C2 produces a novel two-component lantibiotic, termed carnolysin, homologous to enterococcal cytolysin. This lantibiotic is antimicrobially inactive when tested against the non-bacteriocinogenic strain C. maltaromaticum A9b-, likely requiring an additional proteolytic cleavage to reach maturity.
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DSTYK kinase domain ablation impaired the mice capabilities of learning and memory in water maze test.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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DSTYK (Dual serine/threonine and tyrosine protein kinase) is a putative dual Ser/Thr and Tyr protein kinase with unique structural features. It is proposed that DSTYK may play important roles in brain because of its high expression in most brain areas. In the present study, a DSTYK knockout (KO) mouse line with the ablation of C-terminal of DSTYK including the kinase domain was generated to study the physiological function of DSTYK. The DSTYK KO mice are fertile and have no significant morphological defects revealed by Nissl staining compared with wildtype mice. Open field test and rotarod test showed there is no obvious difference in basic motor and balance capacity between the DSTYK homozygous KO mice and DSTYK heterozygous KO mice. In water maze test, however, the DSTYK homozygous KO mice show impaired capabilities of learning and memory compared with the DSTYK heterozygous KO mice.
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Knockdown of protein tyrosine phosphatase receptor U inhibits growth and motility of gastric cancer cells.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Protein tyrosine phosphatase receptor U (PTPRU) has been shown to be a tumor suppressor in colon cancer by dephosphorylating ?-catenin and reducing the activation of ?-catenin signaling. Here, we investigate the expression of PTPRU protein in gastric cancer cell lines, gastric cancer tissues and respective adjacent non-cancer tissues and find that the 130kDa nuclear-localized PTPRU fragment is the main PTPRU isoform in gastric cancer cells, whereas the full-length PTPRU is relatively lowly expressed. The level of the 130kDa PTPRU is higher in gastric cancer tissues than in adjacent non-cancer tissues. Knockdown of endogenous PTPRU in gastric cancer cells using lentivirus-delivered specific shRNA results in the attenuation of cell growth, migration, invasion and adhesion. Knockdown of PTPRU also inhibits tyrosine phosphorylation and transcriptional activity of ?-catenin as well as levels of focal adhesion proteins and lysine methylation of histone H3. These results indicate that PTPRU is required for gastric cancer progression and may serve as a potential therapeutic target.
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Androglobin knockdown inhibits growth of glioma cell lines.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Globin family was famous for oxygen supply function of its members such as hemoglobin and myoglobin. With the progress of research, several members of this protein family have been proven to play roles in tumors including glioma. Androglobin (ADGB) is a recently identified member of globin family with very few studies about its function. In the present study, we show that ADGB plays an oncogene role in glioma. Lentiviral vector mediated ADGB knockdown inhibited the proliferation of glioma cell lines determined by MTT assay and colony formation assay. ADGB knockdown also increased the apoptosis of glioma cell line U251 assessed by flow cytometry. In addition, western blot showed that ADGB knockdown altered levels of several proteins related to proliferation, survival or apoptosis in U251 cells. These findings suggest ADGB is involved in the progression of glioma in vitro.
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Accurate and economical detection of ALK positive lung adenocarcinoma with semiquantitative immunohistochemical screening.
PLoS ONE
PUBLISHED: 01-01-2014
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Right detection of anaplastic lymphoma kinase (ALK) gene rearrangement is pivotal to selection of patients with lung adenocarcinoma for ALK-targeted therapy. We explored the potential of combination of immunohistochemistry (IHC) screening and fluorescence in situ hybridization (FISH) as an affordable practice. We analyzed 410 unselected lung adenocarcinomas by ALK IHC (D5F3 clone) and FISH. Some equivocal cases were further analyzed by RT-PCR. The EGFR mutation was detected by pyrosequencing assay. In total 368 cases which got all IHC, FISH, EGFR mutation results were eligible for analysis. Cases were evaluated as IHC score 3+ (n = 26), score 2+ (n = 9), score 1+ (n = 51), and score 0 (n = 282), respectively. 23 of 26 IHC 3+ and 5 of 9 IHC 2+ cases were FISH positive, whereas 3 of 26 IHC 3+, 4 of 9 IHC 2+ and all 333 IHC 1+/0 cases were FISH negative. If considering FISH as the standard, the sensitivity and specificity of ALK IHC 3+/2+ as ALK positive were 100% and 97.9%, respectively. Three IHC 3+ cases reported as FISH "negative" were actually ALK positive confirmed by ALK RT-PCR or re-detected. Based on the final classify, ALK IHC 3+/2+ was 100% sensitive and 98.8% specific. However, FISH was 90.3% sensitive and 100% specific. IHC 2+ was regarded as equivocal and need to be confirmed by FISH or RT-PCR. In the 368 cases, 8.4% cases had ALK positive, 52.2% cases had EGFR mutation, and only one case had a coexisting. Manually semiquantitative ALK IHC (primary antibody D5F3 coupled with secondary DAKO Envision system) used as the initial screening combined with auxiliary FISH confirmation is a reliable, economical approach to identify ALK positive lung adenocarcinoma. The IHC can find some ALK positive cases which would be missed by FISH only.
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Performance comparison between rapid sequencing platforms for ultra-low coverage sequencing strategy.
PLoS ONE
PUBLISHED: 01-01-2014
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Ultra-low coverage sequencing (ULCS) is one of the most promising strategies for sequencing based clinical application. These clinical applications, especially prenatal diagnosis, have a strict requirement of turn-around-time; therefore, the application of ULCS is restricted by current high throughput sequencing platforms. Recently, the emergence of rapid sequencing platforms, such as MiSeq and Ion Proton, brings ULCS strategy into a new era. The comparison of their performance could shed lights on their potential application in large-scale clinic trials. In this study, we performed ULCS (<0.1X coverage) on both MiSeq and Ion Proton platforms for 18 spontaneous abortion fetuses carrying aneuploidy and compared their performance on different levels. Overall basic data and GC bias showed no significant difference between these two platforms. We also found the sex and aneuploidy detection indicated 100% sensitivity and 100% specificity on both platforms. Our study generated essential data from these two rapid sequencing platforms, which provides useful reference for later research and potentially accelerates the clinical applications of ULCS.
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ITE and TCDD differentially regulate the vascular remodeling of rat placenta via the activation of AhR.
PLoS ONE
PUBLISHED: 01-01-2014
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Vascular remodeling in the placenta is essential for normal fetal development. The previous studies have demonstrated that in utero exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, an environmental toxicant) induces the intrauterine fetal death in many species via the activation of aryl hydrocarbon receptor (AhR). In the current study, we compared the effects of 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) and TCDD on the vascular remodeling of rat placentas. Pregnant rats on gestational day (GD) 15 were randomly assigned into 5 groups, and were exposed to a single dose of 1.6 and 8.0 mg/kg body weight (bw) ITE, 1.6 and 8.0 µg/kg bw TCDD, or an equivalent volume of the vehicle, respectively. The dams were sacrificed on GD20 and the placental tissues were gathered. The intrauterine fetal death was observed only in 8.0 µg/kg bw TCDD-exposed group and no significant difference was seen in either the placental weight or the fetal weight among all these groups. The immunohistochemical and histological analyses revealed that as compared with the vehicle-control, TCDD, but not ITE, suppressed the placental vascular remodeling, including reduced the ratio of the placental labyrinth zone to the basal zone thickness (at least 0.71 fold of control), inhibited the maternal sinusoids dilation and thickened the trophoblastic septa. However, no marked difference was observed in the density of fetal capillaries in the labyrinth zone among these groups, although significant differences were detected in the expression of angiogenic growth factors between ITE and TCDD-exposed groups, especially Angiopoietin-2 (Ang-2), Endoglin, Interferon-? (IFN-?) and placenta growth factor (PIGF). These results suggest ITE and TCDD differentially regulate the vascular remodeling of rat placentas, as well as the expression of angiogenic factors and their receptors, which in turn may alter the blood flow in the late gestation and partially resulted in intrauterine fetal death.
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Propranolol inhibits angiogenesis via down-regulating the expression of vascular endothelial growth factor in hemangioma derived stem cell.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Oral propranolol (PRN) has recently been shown to be highly effective for infantile hemangiomas (IHs), and is currently recommended as the first-line treatment of complicated IHs. However, the therapeutic mechanism(s) still remain unclear.
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[Reversing Effects of Emodin on Multidrug Resistance in Resistant HL-60/ADR Cells].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 12-28-2013
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This study was aimed to investigate the reversing effects of emodin on multidrug resistance (MDR) in resistant HL-60/ADR cells, and to explore the underlying mechanisms. The MTT assay was used to assess the chemoresistance of HL-60/ADR cells to emodin and 8 chemotherapeutic agents commonly used in clinic. The reversal effects of emodin on MDR of HL-60/ADR cells were also evaluated by MTT method. DNA ploid analysis and DNA Ladder assay were used to detect apoptosis-induced effects on HL-60/ADR cells via the adriamycin (ADR) and emodin combination. The expression changes of the drug resistance-associated genes and proteins were detected by RT-PCR and Western Blot respectively. The intracellular accumulation and subcellular distribution of ADR and DNR were measured by flow cytometry and confocal laser scanning microscopy. The results showed that emodin inhibited HL-60/ADR cell proliferation with an average IC50 value of 24.09 ± 1.72 µmol/L, which was similar to that of the parental HL-60 cells (average IC50 = 23.18 ± 0.87 µmol/L).HL-60/ADR cells were resistant to a variety of chemotherapeutic agents, such as ADR, DNR, VP16, VCR,Ara-C, HHT, MTZ and THP. The reversal multiple were between 1.58 and 4.12 after the treatment with low concentration of emodin combined with the above mentioned different agents. The combination of ADR with emodin showed the best reversal effects, and the typical hypodiploid peak (apoptotic peak) and DNA ladder could be detected after the co-treatment.In addition, emodin down-regulated the mRNA and protein expression levels of MRP1, TOPOII?,GST ? and BCL-2. Furthermore, the addition of emodin enhanced ADR and DNR intracellular accumulation and subcellular distribution in HL-60/ADR cells in dose-dependent manner. It is concluded that the emodin shows reversing effects on the multidrug resistant HL-60/ADR cells, possibly via decreasing the expression levels of drug resistance-associated genes, increasing the intracellular accumulation of chemotherapeutic agents and activating the apoptosis pathway.
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Polybrominated Diphenyl Ethers (PBDEs) in Paired Human Hair and Serum from e-Waste Recycling Workers: Source Apportionment of Hair PBDEs and Relationship between Hair and Serum.
Environ. Sci. Technol.
PUBLISHED: 12-16-2013
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Human hair has been widely used as a bioindicator for human persistent organic pollutants (POPs) exposure, but studies on the sources of hair POPs and the relationship between hair and body burden are limited. This study analyzed the possible source apportionment of hair PBDEs and examined the relationship between PBDE concentrations in paired hair and serum from e-waste recycling workers. Using the ratio of BDE 99/47 and BDE 209/207 as indices, we calculated that only 15% of the highly brominated congeners (nona- and deca-BDE congeners) comes from exogenous (external) exposure for both female and male hair, but an average of 64% and 55% of the lower-brominated congeners (tetra- to penta-BDE congeners) come from exogenous exposure for female and male hair, respectively. The higher contribution of exogenous exposure for less-brominated congeners could be related to their relatively lower log KOW and higher volatility than higher-brominated congeners, which make them more readily to evaporate from dust and then to be adsorbed on hair. Higher hair PBDE levels and higher exogenous exposure of less-brominated congeners in females than in males can be attributed to a longer exogenous exposure time for females than males. Significant positive relationships were found in tri- to hepta-BDE congeners (BDE 28, 47, 66, 85, 100, 153, 154, and 183) (R = 0.36-0.55, p < 0.05) between hair and serum, but this relationship was not found for octa- to deca-BDE. Difference in the half-lives between highly brominated congeners and less-brominated congeners could be a reason. This result also implied that we should treat the results of correlation analyses between hair and other organs cautiously.
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Paraoxonase activity and genetic polymorphisms in northern Han Chinese workers exposed to organophosphate pesticides.
Exp. Biol. Med. (Maywood)
PUBLISHED: 12-10-2013
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Paraoxonase (PON1) is one of the major players in the detoxification of organophosphates (OPs). This study presents our investigation into the effect of OPs on serum PON1 activity and the distribution of common PON1 polymorphisms in Han Chinese workers with repeated high exposure to OP pesticides, and the factors modulating PON1 activity. In all, 400 participants, including 180 workers exposed to OP pesticides occupationally, and 220 controls were investigated. Serum PON1 and cholinesterase (ChE) activity were measured, and genotyping was done using polymerase chain reaction-restriction fragment length polymorphism. The association between PON1 activity and PON1 polymorphisms, and the influencing factors of PON1 activity, were analyzed. The results revealed that repeated OP exposures significantly decreased serum PON1 and ChE activity (P?
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Marshalin, a microtubule minus-end binding protein, regulates cytoskeletal structure in the organ of Corti.
Biol Open
PUBLISHED: 11-15-2013
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Dramatic structural changes in microtubules (MT) and the assembly of complicated intercellular connections are seen during the development of the cellular matrix of the sense organ for hearing, the organ of Corti. This report examines the expression of marshalin, a minus-end binding protein, during this process of cochlear development. We discovered that marshalin is abundantly expressed in both sensory hair cells and supporting cells. In the adult, prominent marshalin expression is observed in the cuticular plates of hair cells and in the noncentrosomal MT organization centers (MTOC) of Deiters and pillar cells. Based upon differences in marshalin expression patterns seen in the organ of Corti, we identified eight isoforms ranging from 863 to 1280 amino acids. mRNAs/proteins associated with marshalins isoforms are detected at different times during development. These isoforms carry various protein-protein interacting domains, including coiled-coil (CC), calponin homology (CH), proline-rich (PR), and MT-binding domains, referred to as CKK. We, therefore, examined membranous organelles and structural changes in the cytoskeleton induced by expressing two of these marshalin isoforms in vitro. Long forms containing CC and PR domains induce thick, spindle-shaped bundles, whereas short isoforms lacking CC and PR induce more slender variants that develop into densely woven networks. Together, these data suggest that marshalin is closely associated with noncentrosomal MTOCs, and may be involved in MT bundle formation in supporting cells. As a scaffolding protein with multiple isoforms, marshalin is capable of modifying cytoskeletal networks, and consequently organelle positioning, through interactions with various protein partners present in different cells.
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Self-assembly of graphene oxide with a silyl-appended spiropyran dye for rapid and sensitive colorimetric detection of fluoride ions.
Anal. Chem.
PUBLISHED: 11-14-2013
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Fluoride ion (F(-)), the smallest anion, exhibits considerable significance in a wide range of environmental and biochemical processes. To address the two fundamental and unsolved issues of current F(-) sensors based on the specific chemical reaction (i.e., the long response time and low sensitivity) and as a part of our ongoing interest in the spiropyran sensor design, we reported here a new F(-) sensing approach that, via assembly of a F(-)-specific silyl-appended spiropyran dye with graphene oxide (GO), allows rapid and sensitive detection of F(-) in aqueous solution. 6-(tert-Butyldimethylsilyloxy)-1,3,3-trimethylspiro [chromene- 2,2-indoline] (SPS), a spiropyran-based silylated dye with a unique reaction activity for F(-), was designed and synthesized. The nucleophilic substitution reaction between SPS and F(-) triggers cleavage of the Si-O bond to promote the closed spiropyran to convert to its opened merocyanine form, leading to the color changing from colorless to orange-yellow with good selectivity over other anions. With the aid of GO, the response time of SPS for F(-) was shortened from 180 to 30 min, and the detection limit was lowered more than 1 order of magnitude compared to the free SPS. Furthermore, due to the protective effect of nanomaterials, the SPS/GO nanocomposite can function in a complex biological environment. The SPS/GO nanocomposite was characterized by XPS and AFM, etc., and the mechanism for sensing F(-) was studied by (1)H NMR and ESI-MS. Finally, this SPS/GO nanocomposite was successfully applied to monitoring F(-) in the serum.
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[Efficacy of CALLG2008 protocol in treatment of adult acute lymphoblastic leukemia: a single center analysis].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 09-04-2013
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CALLG2008 Protocol is sequential chemotherapy for adult acute lymphoblastic leukemia (ALL) established by Collaborative Group of adults acute lymphoblastic leukemia. It is emphasized that comprehensive treatment of adult ALL according to risk stratification is rather important. This study was purposed to evaluate the therapeutic efficacy of CALLG2008 for adult ALL. The clinical data of adult ALL patients of ? 14 years old diagnosed and treated by CALLG2008 Protocol were collected from May 1, 2009 to December 31, 2011 in Fujian Medical University Union Hospital, and the efficacy was analyzed. The results showed that 31 out of 33 cases of ALL achieved CR, the CR rate was up to 93.9%, the PR rate was 3.1%, and the total response rate was 97%. There were no uncontrolled severe toxicities, and no early deaths were observed. The overall survival (OS) at 1 year was only 66.7%,the relapse rate was 43.8% and the 1-year mortality was 33.3 %. This may be related with no-enough compliance, no-enough economical support and short follow-up time of the patients. The risk factor analysis showed that WBC level in newly diagnosed patients may influence the OS and relapse-free survival (RFS) of ALL. It is concluded that CALLG2008 protocol applied to adult ALL has a high remission quality and low mortality rate during the induction. The disease free survival (DFS) needs to be observed longer. It is essential to carry out MRD monitoring to determine the early recurrence and improving the long-term efficacy.
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Inactivation of ?-catenin results in the reduction of postnatal body weight gain.
Brain Res. Bull.
PUBLISHED: 09-01-2013
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Arcuate nucleus of hypothalamus (ARH) is the core component in the regulation circuits of food intake and energy homeostasis. ARH projections to other parts of the hypothalamus and to extrahypothalamic areas are established in the postnatal two weeks, which is a pivotal stage for individual development. ?-Catenin, a cell adhesion protein and also the mediator of canonical Wnt signaling pathway, plays an important role in embryonic development and adult homeostasis. However, whether ?-catenin plays any roles in the development of hypothalamus is not clear. Here, we report that perinatal conditional knockout of ?-catenin by CamKII?-Cre in forebrain reduces body weight gain from P8 and dramatically shortens life span. Quantitative PCR and in situ hybridization results showed the expression of NPY mRNA in the ARH of ?-catenin CKO mice at P15 is obviously increased compared with that of littermate controls, whereas the expression of POMC mRNA is significantly decreased, which suggested the reduction of postnatal body weight gain might be due to the deficiency of food intake. Together, ?-catenin might play an important role in the regulation of food intake and postnatal body weight gain probably through affecting the development of ARH circuits.
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Exploiting the higher specificity of silver amalgamation: selective detection of mercury(II) by forming Ag/Hg amalgam.
Anal. Chem.
PUBLISHED: 08-26-2013
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Heavy metal ion pollution poses severe risks in human health and the environment. Driven by the need to detect trace amounts of mercury, this article demonstrates, for the first time, that silver/mercury amalgamation, combining with DNA-protected silver nanoparticles (AgNPs), can be used for rapid, easy and reliable screening of Hg(2+) ions with high sensitivity and selectivity over competing analytes. In our proposed approach, Hg(2+) detection is achieved by reducing the mercury species to elemental mercury, silver atoms were chosen as the mercury atoms acceptors by forming Ag/Hg amalgam. To signal fluorescently this silver amalgamation event, a FAM-labeled ssDNA was employed as the signal reporter. AgNPs were grown on the DNA strand that resulted in greatly quenching the FAM fluorescence. Formation of Ag/Hg amalgam suppresses AgNPs growth on the DNA, leading to fluorescence signal increase relative to the fluorescence without Hg(2+) ions, as well as marked by fluorescence quenching. This FAM fluorescence enhancement can be used for detection of Hg(2+) at the a few nanomolar level. Moreover, due to excellent specificity of silver amalgamation with mercury, the sensing system is highly selective for Hg(2+) and does not respond to other metal ions with up to millimolar concentration levels. This sensor is successfully applied to determination of Hg(2+) in tap water, spring water and river water samples. The results shown herein have important implications in the development of new fluorescent sensors for the fast, easy, and selective detection and quantification of Hg(2+) in environmental and biological samples.
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Y-SNPs haplotype diversity in four Chinese cattle breeds.
Anim. Biotechnol.
PUBLISHED: 08-17-2013
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To investigate the genetic diversity of Chinese cattle, 96 male samples of 4 Chinese native cattle breeds were investigated using 5 single nucleotide polymorphisms specific to the bovine Y chromosome. Two previously described haplotypes (taurine Y2 and indicine Y3) were detected in 74 and 22 animals, respectively. The haplotype frequencies varied amongst the four native breeds. The taurine Y2 haplotype dominated in the Qinchuan, Dabieshan, and Yunba breeds. However, the indicine Y3 haplotype occurred in high frequency in the Enshi breed. Among the four native breeds, Yunba had the highest haplotype diversity (0.4330 ± 0.0750), followed by Qinchuan (0.2899 ± 0.1028) and Enshi (0.2222 ± 0.1662), Dabieshan was the least differentiated (0.1079 ± 0.0680). Compared with some foreign cattle breeds, the low level of haplotype diversity was detected in our breeds (0.2633 ± 0.1030).
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Evidences for the existence of intermolecular disulfide-bonded oligomers in the H3 hemagglutinins expressed in insect cells.
Virus Genes
PUBLISHED: 08-15-2013
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The hemagglutinin (HA) protein as the predominant antigen, executes receptor binding and membrane fusion, which critically influence the virological characteristics of influenza viruses. The literature contained scattered data showing reduction-sensitive HA oligomers when HA proteins were analyzed under non-reducing conditions. However, whether the reduction-sensitive HA oligomers are inter-monomer disulfide-bonded has not been studied. Here, we showed: (1) the detection of ?-mercaptoethanol-sensitive H3 HA oligomers was not affected by the treatment of cells with iodoacetamide prior to cell solubilization; (2) H3 HA oligomers were present on cell surfaces; (3) H3 HA oligomers had higher density than monomers; and (4) mutation of all the five C-terminal cysteines completely abolished the formation of H3 HA oligomers. Furthermore, mutant HAs with mutations of TM cysteines, CT cysteines or all five cysteines had decreased thermal stability but increased fusion activity in comparison with wildtype HA. In conclusion, this study has presented enough evidence for the existence of inter-monomer S-S H3 HA oligomers formed by five C-terminal cysteines, and suggested that all five C-terminal cysteines exerted opposite effects on HA thermal stability and fusion activity.
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A gold nanocarrier and DNA-metal ligation-based sensing ensemble for fluorescent assay of thiol-containing amino acids and peptides.
Chem. Commun. (Camb.)
PUBLISHED: 07-30-2013
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By engineering a gold nanoparticle and thymine-Hg(2+)-thymine-based hairpin DNA probe, a gold nanocarrier-based strategy for in vitro detection and live-cell imaging of thiol-containing amino acids/peptides was proposed.
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Ultrathin W18O49 nanowire assemblies for electrochromic devices.
Nano Lett.
PUBLISHED: 07-25-2013
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Ordered W18O49 nanowire thin films were fabricated by Langmuir-Blodgett (LB) technique in the presence of poly(vinyl pyrrolidone) coating. The well-organized monolayer of W18O49 nanowires with periodic structures can be readily used as electrochromic sensors, showing reversibly switched electrochromic properties between the negative and positive voltage. Moreover, the electrochromism properties of the W18O49 nanowire films exhibit significant relationship with their thickness. The coloration/bleaching time was around 2 s for the W18O49 nanowire monolayer, which is much faster than the traditional tungsten oxide nanostructures. Moreover, the nanowire devices display excellent stability when color switching continues, which may provide a versatile and promising platform for electrochromism device, smart windows, and other applications.
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A spherical nucleic acid platform based on self-assembled DNA biopolymer for high-performance cancer therapy.
ACS Nano
PUBLISHED: 07-23-2013
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Based on their enhanced cellular uptake, stability, biocompatibility, and versatile surface functionalization, spherical nucleic acids (SNAs) have become a potentially useful platform in biological applications. It still remains important to expand the SNAs "toolbox", especially given the current interest in multimodal or theranostic nanomaterials, that is, composites capable of multiple simultaneous applications such as imaging, sensing, and drug delivery. In this paper, we have engineered a nanoparticle-conjugated initiator that triggers a cascade of hybridization reactions resulting in the formation of a long DNA polymer as the nanoparticle shell. By employing different DNA fragments, self-assembled multifunctional SNAs can be constructed. Therefore, using one capped ligand, these SNAs can combine imaging fluorescent tags, target recognition element, and targeted delivery molecules together. Since these SNAs possess high drug loading capacity and high specificity by the incorporation of an aptamer, our approach might find potential applications in new drug development, existing drug improvement, and drug delivery for cancer therapy.
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Time-resolved fluorescent detection of Hg2+ in a complex environment by conjugating magnetic nanoparticles with a triple-helix molecular switch.
Chem. Commun. (Camb.)
PUBLISHED: 06-26-2013
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In this communication, we molecularly engineered a light-switching excimer oligonucleotide-based probe for time-resolved fluorescent detection of Hg(2+). By combining a time-resolved fluorescence technique and magnetic nanoparticles, Hg(2+) spiked in human urine was detected.
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Determination of Three Phthalate Esters in Environmental Samples by Coal Cinder Extraction and Cyclodextrin Modified Micellar Electrokinetic Chromatography.
J Chromatogr Sci
PUBLISHED: 06-21-2013
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A new micellar electrokinetic chromatography (MEKC) method using beta-cyclodextrin (ß-CD) as the electrophoresis additive has been developed for the simultaneous determination of dimethyl phthalate (DMP), diethyl phthalate (DEP) and di(2-ethylhexyl) phthalate (DEHP) in environmental samples. To improve the sensitivity of cyclodextrin-modified MEKC (CD-MEKC), a flow injection procedure using a microcolumn packed with coal cinder as the solid-phase extractant was also investigated for the preconcentration and separation of DMP, DEP and DEHP in environmental samples. Parameters affecting CD-MEKC separation and coal cinder flow injection solid-phase extraction were systematically researched. In the presence of the running buffer [5 mmol/L of borax, 5% (v/v) methanol and 25 mmol/L of sodium dodecyl sulfate at pH 9.5], the addition of 14 mmol/L ß-CD greatly improved the separation efficiency. The analytes were quantitatively adsorbed by coal cinders and readily desorbed quantitatively with 0.2 mL of 10% (v/v) methanol-10 mmol/L disodium hydrogen phosphate. Under the optimum conditions, the enrichment factor of coal cinder was 60, and the determination limits of DMP, DEP and DEHP were 3.07, 2.07 and 4.06 ng/mL, respectively. The presented procedure was successfully applied to determine DMP, DEP and DEHP in landfill leachate and water samples with satisfactory results.
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[Mitochondrial tRNAIle A4317G mutation may influence the phenotypic manifestation of deafness-associated 12S rRNA A1555G mutation].
Yi Chuan
PUBLISHED: 06-19-2013
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Mitochondrial 12S rRNA A1555G mutation has been associated with both aminoglycoside-induced and nonsyndromic hearing loss. In this report, we performed a clinical and genetic evaluation, and mitochondrial genome analysis of one hearing-impaired Chinese family carrying the A1555G mutation. Strikingly, the penetrances of hearing loss in this family, which were 81% and 66.7%, respectively, when aminoglycoside-induced hearing loss was included or excluded. The penetrances of hearing loss in this family were significantly higher than those in other Chinese families carrying the A1555G mutation. Sequence analysis of their mitochondrial genomes revealed the presence of homoplasmic tRNAIle A4317G mutations and 38 mtDNA polymorphisms belonging to East-Asian haplogroup B4c1b2. Further analysis revealed that other mitochondrial DNA variants were not functional significantly, while the A4317G mutation is localized to a highly conserved nucleotide (conventional site 59) at tRNAIle T?C loop of tRNAIle. The mutation may alter secondary structure and function of this tRNA, thereby leading to mitochondrial dysfunction. Allelic analysis showed that this mutation was absent in 961 hearing normal Chinese controls. Thus, the altered tRNAIle metabolism by the A4317G mutation may aggravate mitochondrial dysfunction associated with the A1555G mutation, and contribute to the higher penetrance of hearing loss. Therefore, the tRNAIle A4317G mutation may act as a mitochondrial modifier to influence the phenotypic manifestation of the A1555G mutation.
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The association of Chinese hospital work environment with nurse burnout, job satisfaction, and intention to leave.
Nurs Outlook
PUBLISHED: 06-18-2013
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The purpose of this study was to describe nurse burnout, job satisfaction, and intention to leave and to explore the relationship of work environment to nursing outcomes in a sample of 9,698 nurses from 181 hospitals in China. Nurses reported moderate levels of emotional exhaustion and depersonalization and high levels of reduced personal accomplishment. Nearly one-fifth of the nurses reported high levels of burnout on all three dimensions. Forty-five percent of the nurses were dissatisfied with their current job; these nurses were most dissatisfied with their salary. Five percent of nurses reported an intention to leave. Nurses reporting mixed and good work environments were less likely to report high burnout, job dissatisfaction, and intention to leave compared with those in poor work environments. The results suggest that high burnout and low job satisfaction are prominent problems for Chinese nurses, and improving work environment might be an effective strategy for better nursing outcomes in Chinese hospitals.
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Molecule-binding dependent assembly of split aptamer and ?-cyclodextrin: a sensitive excimer signaling approach for aptamer biosensors.
Anal. Chim. Acta
PUBLISHED: 06-14-2013
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A highly sensitive and selective fluorescence aptamer biosensors for the determination of adenosine triphosphate (ATP) was developed. Binding of a target with splitting aptamers labeled with pyrene molecules form stable pyrene dimer in the ?-cyclodextrin (?-CD) cavity, yielding a strong excimer emission. We have found that inclusion of pyrene dimer in ?-cyclodextrin cavity not only exhibits additive increases in quantum yield and emission lifetime of the excimer, but also facilitates target-induced fusion of the splitting aptamers to form the aptamer/target complex. As proof-of-principle, the approach was applied to fluorescence detection of adenosine triphosphate. With an anti-ATP aptamer, the approach exhibits excimer fluorescence response toward ATP with a maximum signal-to-background ratio of 32.1 and remarkably low detection limit of 80 nM ATP in buffer solution. Moreover, due to the additive fluorescence lifetime of excimer induced by ?-cyclodextrin, time-resolved measurements could be conveniently used to detect as low as 0.5 ?M ATP in blood serum quantitatively.
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Estradiol 17? and its metabolites stimulate cell proliferation and antagonize ascorbic Acid-suppressed cell proliferation in human ovarian cancer cells.
Reprod Sci
PUBLISHED: 06-11-2013
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Estradiol 17? (E2?) and ascorbic acid (AA) have been implicated in cancer progression. However, little is known about the actions of biologically active metabolites of E2?, 2-hydroxyestradiol (2OHE2), 4-hydroxyestradiol (4OHE2), 2-methoxyestradiol (2ME2), and 4-methoxyestradiol (4ME2) synthesized sequentially by cytochrome P450, family 1, subfamily A (CYP1A1) and B (CYP1B1), polypeptide 1, and catechol-O-methyltransferase (COMT) on ovarian cancer. Herein, we examined the expression of CYP1A1, CYP1B1, COMT, and estrogen receptor ? (ER?) and ? (ER?) in human ovarian surface epithelial (IOSE-385) and cancer cell lines (OVCAR-3, SKOV-3, and OVCA-432). We also investigated the roles of E2?, 2OHE2, 4OHE2, 2ME2, and 4ME2 in cell proliferation, and their interactive effects with AA on ovarian cells. We found the expression of CYP1A1, CYP1B1, COMT, ER?, and ER? in most cell lines tested. Treating cells with physiological concentrations of E2? and its metabolites promoted (13%-42% of the control) IOSE-385 and OVCAR-3 proliferation. The ER blockade inhibited IOSE-385 (?76%) and OVCAR-3 (?87%) proliferative response to E2? but not to its metabolites. The ER? blockade inhibited (?85%) E2?-stimulated OVCAR-3 proliferation, whereas ER? blockade attenuated (?83%) E2?-stimulated IOSE-385 proliferation. The AA at ?250 ?mol/L completely inhibited serum-stimulated cell proliferation in all cell lines tested; however, such inhibition in IOSE-385, OVCAR-3, and OVCA-432 was partially (?10%-20%) countered by E2? and its metabolites. Thus, our findings indicate that E2? and its metabolites promote cell proliferation and antagonize the AA-suppressed cell proliferation in a subset of ovarian cancer cells, suggesting that blocking the actions of E2? and its metabolites may enhance AAs antiovarian cancer activity.
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Aptamer degradation inhibition combined with DNAzyme cascade-based signal amplification for colorimetric detection of proteins.
Chem. Commun. (Camb.)
PUBLISHED: 06-04-2013
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Combining the inhibition of aptamer degradation with DNA Enzyme (DNAzyme) cascade-based signal amplification, a label-free and sensitive colorimetric protein assay strategy was proposed.
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Heavy metals in food, house dust, and water from an e-waste recycling area in South China and the potential risk to human health.
Ecotoxicol. Environ. Saf.
PUBLISHED: 05-30-2013
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Concentrations of heavy metals (Cd, Pb, Cu, Zn, and Ni) were measured in the foodstuffs, house dust, underground/drinking water, and soil from an electronic waste (e-waste) area in South China. Elevated concentrations of these potentially toxic metals were observed in the samples but not in drinking water. The health risks for metal exposure via food consumption, dust ingestion, and drinking water were evaluated for local residents. For the average residents in the e-waste area, the non-carcinogenic risks arise predominantly from rice (hazard index=3.3), vegetables (2.2), and house dust (1.9) for adults, while the risks for young children are dominated by house dust (15). Drinking water may provide a negligible contribution to risk. However, local residents who use groundwater as a water supply source are at high non-carcinogenic risk. The potential cancer risks from oral intake of Pb are 8×10(-5) and 3×10(-4) for average adults and children, and thus groundwater would have a great potential to induce cancer (5×10(-4) and 1×10(-3)) in a highly exposed population. The results also reveal that the risk from oral exposure is much higher than the risk from inhalation and dermal contact with house dust.
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Photoluminescence behavior of europium (III) complexes containing 1-(4-tert-butylphenyl)-3-(2-naphthyl)-propane-1,3-dione ligand.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 05-16-2013
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Three novel europium complexes with 1-(4-tert-butylphenyl)-3-(2-naphthyl)-propane-1,3-dione (TNPD) and 2,2-dipyridine (Bipy) or 1,10-phenan-throline (Phen) were synthesized and confirmed by FT-IR, (1)H NMR, UV-vis absorption and elemental analysis. Photoluminescence behavior of complexes Eu(TNPD)3, Eu(TNPD)3·Bipy and Eu(TNPD)3·Phen were investigated in detail. Their emission spectra exhibited the characteristic emission bands that arise from the (5)D0?(7)FJ (J=0-4) transitions of the europium ion in solid state. Meanwhile, the results of their lifetime decay curves indicated that only one chemical environment existed around the europium ion. The intrinsic luminescence quantum efficiency (?) and the experimental intensity parameters (?t) of europium complexes were determined according to the emission spectra and luminescence decay curves in solid state. The complex Eu(TNPD)3·Phen showed much longer lifetime (?) and higher luminescence quantum efficiency (?) than complexes Eu(TNPD)3 and Eu(TNPD)3·Bipy.
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