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Find video protocols related to scientific articles indexed in Pubmed.
Effectiveness and Safety of Lower Doses of Mifepristone Combined With Misoprostol for the Termination of Ultra-Early Pregnancy: A Dose-Ranging Randomized Controlled Trial.
Reprod Sci
PUBLISHED: 11-15-2014
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This study aimed to investigate the effectiveness and safety of lower doses of mifepristone combined with misoprostol for the termination of ultra-early pregnancy. A total of 2500 women with ultra-early pregnancy (amenorrhea ? 35 days) were randomly divided into 5 groups with gradually decreased dose of oral mifepristone from 150 to 50 mg followed by 200 µg of oral misoprostol 24 hours later. The primary end point was complete abortion without surgical intervention. Secondary end points were vaginal bleeding, return of menses, and side effects. Rates of complete abortion were high in all groups. Moreover, the lower doses of mifepristone led to shorter vaginal bleeding period, the return of menses on the expected date, and fewer side effects. Lower doses of mifepristone combined with 200 µg of misoprostol are as effective and safe as higher doses of this combination for the termination of ultra-early pregnancy with lower possibility of vaginal bleeding and side effects.
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Preparation and Characterization of Superparamagnetic Molecularly Imprinted Polymers for Selective Adsorption and Separation of Vanillin in Food Samples.
J. Agric. Food Chem.
PUBLISHED: 11-06-2014
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Novel water-compatible superparamagnetic molecularly imprinted polymers (M-MIPs) were prepared by coating superparamagnetic Fe3O4 nanoparticles with MIPs in a methanol-water reaction system. The M-MIPs were used for the selective adsorption and separation of vanillin from aqueous solution. The M-MIPs were characterized by X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), vibrating sample magnetometry (VSM), and scanning electron microscopy (SEM). Results indicated that a core-shell structure of M-MIPs was obtained by coating a layer of silica and MIPs on the surface of the Fe3O4 nanoparticles. The obtained M-MIPs possess a loose and porous structure and can be rapidly separated from the solution using a magnet. The adsorption experiments showed that the binding capacity of the M-MIPs was significantly higher than that of the superparamagnetic non-molecularly imprinted polymers (M-NIPs). Meanwhile, the adsorption of M-MIPs reached equilibrium within 100 min, and the apparent maximum adsorption quantity (Qmax) and dissociation constant (Kd) were 64.12 ?mol g(-1) and 58.82 ?mol L(-1), respectively. The Scatchard analysis showed that homogeneous binding sites were formed on the M-MIP surface. The recoveries of 83.39-95.58% were achieved when M-MIPs were used for the pre-concentration and selective separation of vanillin in spiked food samples. These results provided the possibility for the separation and enrichment of vanillin from complicated food matrices by M-MIPs.
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Base-switched annuloselectivity in the reactions of ethyl malonyl chloride and imines.
Org. Biomol. Chem.
PUBLISHED: 10-30-2014
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The base-switched annuloselectivity, namely [2 + 2] and [2 + 2 + 2] selectivity, in the reactions of ethyl malonyl chloride and imines is successfully realized. In the presence of the weak nucleophilic base 2-chloropyridine, the reactions deliver ethyl trans-?-lactam-3-carboxylates as the exclusive [2 + 2] products in up to 93% yields, while with the strong nucleophilic N-methylimidazole as the base, the reactions give rise to 2,3-dihydro-1,3-oxazin-4-one derivatives as the sole products in up to 99% yields via the formal [2 + 2 + 2] cycloaddition involving one molecule of the imine and two molecules of the ketene generated from malonyl chloride. Notably, ethyl trans-?-lactam-3-carboxylates are synthesized for the first time directly from the reactions of ethyl malonyl chloride and imines. Mechanistic discussions reveal that the annuloselectivity is controlled by the nucleophilicity of organic bases.
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Use of graphene and gold nanorods as substrates for the detection of pesticides by surface enhanced Raman spectroscopy.
J. Agric. Food Chem.
PUBLISHED: 10-15-2014
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This study aimed to use gold nanorods and graphene as key materials to fabricate high-performance substrates for the detection of pesticides by surface enhanced Raman spectroscopy (SERS). Three types of pesticides (azinphos-methyl, carbaryl, and phosmet) were selected. Gold nanorods have great potential to be used as a SERS substrate because it is easy to tune the surface plasmon resonance of the nanorods to the laser excitation wavelength of Raman spectroscopy. Graphene is a promising nanoscale material that can be used for supporting metal nanostructures. Three types of novel SERS substrates were fabricated, including graphene-gold film-gold nanorod (G-Au-AuNR) substrate, gold film-gold nanorod (Au-AuNR) substrate, and graphene coupled with gold nanorods (G-AuNR). The results demonstrate that G-Au-AuNR substrates exhibited the strongest Raman signals of the selected pesticides, followed by the Au-AuNR substrates. G-AuNR exhibited the weakest Raman signals, and no characteristic spectral features of the analytes were obtained. A partial least-squares method was used to develop quantitative models for the analysis of spectral data (R = 0.94, 0.87, and 0.86 for azinphos-methyl, carbaryl, and phosmet, respectively). The G-Au-AuNRs substrate was able to detect all three types of pesticides at the parts per million level with limits of detection at around 5, 5, and 9 ppm for azinphos-methyl, carbaryl, and phosmet, respectively. These results indicate that combining gold nanorods and graphene has great potential in the fabrication of sensitive, lightweight, and flexible substrates for SERS applications to improve food safety.
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[Effect of electroacupuncture intervention on autophagy pathway in APP 695 V 717 I transgenic mice].
Zhen Ci Yan Jiu
PUBLISHED: 09-16-2014
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To observe the effect of electroacupuncture (EA) therapy on the intraneuronal Abeta1-42 and dysfunction of autophagy pathway, so as to reveal its mechanism underlying improvement of Alzheimer's disease (AD).
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Claims, liabilities, injures and compensation payments of medical malpractice litigation cases in China from 1998 to 2011.
BMC Health Serv Res
PUBLISHED: 09-11-2014
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Although China experienced great improvement in their health system, disputes between patients and doctors have increasingly intensified, reaching an unprecedented level. Retrospective analysis of medical malpractice litigation can discover the characteristics and fundamental cause of these disagreements.
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Global and local persistence of influenza A(H5N1) virus.
Emerging Infect. Dis.
PUBLISHED: 07-26-2014
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An understanding of the global migration dynamics of highly pathogenic avian influenza A(H5N1) virus is helpful for surveillance and disease prevention. To characterize the migration network of this virus, we used genetic analysis, which supported a global persistence model in which each of 9 regions acts to some extent as a source. Siberia is the major hub for the dispersal of the virus. Southeast Asia and Africa are major sources of genetically and antigenically novel strains. We found evidence of local persistence of the virus in Southeast Asia and Africa, which is rare for human influenza A viruses. The differences in migration dynamics between avian and human influenza viruses might help with the design of region-specific surveillance efforts and the selection of vaccine candidates.
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A series of 3D metal organic frameworks based on [24-MC-6] metallacrown clusters: structure, magnetic and luminescence properties.
Dalton Trans
PUBLISHED: 07-18-2014
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Four isostructural metal organic frameworks (MOFs), namely [Co6(HipO)6]·6H2O (1), [Mn6(HipO)6]·6H2O (2), [Cd6(HipO)6]·6H2O (3) and [Zn6(HipO)6]·7H2O (4) (H3ipO = 2-hydroxyisophthalic acid), were synthesized and structurally characterized. They have a 3D (4,6)-connected framework based on [24-MC-6] metallacrown clusters ([24-MC-6]-based MOFs). The arrangements of the 24-MC-6 metallacrown SBUs show a regular change indicated by the orientation of their symmetry axes, resulting in a special dense packing mode different from other [24-MC-6]-based MOFs. The analysis of SQUID measurements reveal that compound 1 displays the dominant antiferromagnetic exchanges in 300-10 K between the adjacent Co(II) ions and a ferromagnetic-like behavior at lower temperatures, whereas compound 2 shows an antiferromagnetic interaction between the adjacent Mn(II) ions. Compound 1 exhibits a magnetocaloric effect (MCE) with the resulting entropy change (-?S(m)) of 15.20 J kg(-1) K(-1) for ?H = 50 kG at 6 K, which is the highest value among the cobalt-based MOFs with MCE reported so far. The luminescence properties of compounds 3 and 4 were studied, both of them exhibit photoluminescence in the solid state at room temperature which can be ascribed to intraligand ???* transitions.
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Isolation and purification of a polysaccharide from the caterpillar medicinal mushroom Cordyceps militaris (Ascomycetes) fruit bodies and its immunomodulation of RAW 264.7 macrophages.
Int J Med Mushrooms
PUBLISHED: 06-19-2014
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A novel polysaccharide (CP2-S) was purified from Cordyceps militaris fruit bodies by hot water extraction, ethanol precipitation, DEAE-Sepharose Fast Flow and Sephacryl S-400 high-resolution chromatography. The polysaccharide had a molecular weight of 5.938 × 10(6) g/mol and was mainly composed of glucose. CP2-S had carbohydrate content estimated to be 100% using the phenol-sulfuric acid method. Immunostimulating experiments in vitro indicated that CP2-S could stimulate nitric oxide production, phagocytosis, respiratory burst activity, and secretion of interleukin-1? and interleukin-2 of macrophages, suggesting that this water-soluble polysaccharide from the fruit body of C. militaris is a natural immunostimulating polysaccharide with potential for further application.
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Effect of charge density of polysaccharides on self-assembled intragastric gelation of whey protein/polysaccharide under simulated gastric conditions.
Food Funct
PUBLISHED: 06-13-2014
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This study focuses on the behavior of mixed protein and polysaccharides with different charge densities under simulated gastric conditions. Three types of polysaccharides, namely, guar gum, xanthan gum and carrageenan (neutral, medium negatively, and highly negatively charged, respectively) were selected for heating together with whey protein isolate (WPI) at a biopolymer ratio ranging from 0.01 to 0.1. Upon mixing with simulated gastric fluid (SGF), all WPI-guar gum samples remained soluble, whereas WPI-xanthan gum and WPI-carrageenan at biopolymer ratio higher than 0.01 led to self-assembled intragastric gelation immediately after mixing with SGF. The mechanism behind the intragastric gelation is believed to be the cross-linking between oppositely charged protein and polysaccharides when pH was reduced to below the pI of the protein. Higher biopolymer ratio led to a higher degree of intermolecular interaction, which tends to form stronger gel. More negatively charged carrageenan also formed a stronger gel than xanthan gum. SDS-PAGE results show that the digestibility of protein was not affected by the presence of guar gum as well as xanthan gum and carrageenan at biopolymer ratio lower than 0.02. However, intragastric gel formed by WPI-xanthan gum and WPI-carrageenan at biopolymer ratio higher than 0.02 significantly slows down the digestion rate of protein, which could potentially be used to delay gastric emptying and promote satiety.
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Work stress, work motivation and their effects on job satisfaction in community health workers: a cross-sectional survey in China.
BMJ Open
PUBLISHED: 06-07-2014
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It is well documented that both work stress and work motivation are key determinants of job satisfaction. The aim of this study was to examine levels of work stress and motivation and their contribution to job satisfaction among community health workers in Heilongjiang Province, China.
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Relationships between actual and desired workplace characteristics and job satisfaction for community health workers in China: a cross-sectional study.
BMC Fam Pract
PUBLISHED: 05-27-2014
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BackgroundCommunity health workers are the main providers of community health services in China and have been important in the process of health system reform that has been in place since 2009. Therefore, it is critical that healthcare managers and policy decision makers motivate current staff and improve their job satisfaction. This study examined workplace characteristics and their contribution to job satisfaction in community health workers in Heilongjiang Province, China.MethodsA cross-sectional survey of 448 community health workers, from three cities in Heilongjiang province, was conducted between October 1, 2012 and December 31, 2012. Multistage sampling procedures were used to measure socioeconomic and demographic status, job satisfaction, and both actual and desired workplace characteristics. Factor analysis was conducted to determine the main factors contributing to workplace characteristics, and multiple linear regression analysis was performed to assess the key determinants of job satisfaction.ResultsEight groups of factors were identified as the most important workplace characteristics. These comprised system and policy; fringe benefits; work itself; work relationships; professional development; recognition; work environment; and remuneration. In all cases, all desired workplace characteristics were higher than the associated actual workplace characteristics. The main determinants of job satisfaction were occupation, years worked in health service institution, and five subscales representing the gap between desired and actual workplace characteristics, which were system and policy; fringe benefits; working relationship; professional development; and remuneration.ConclusionsThese findings suggested that managers wishing to enhance job satisfaction should assess workplace characteristics comprehensively and design mechanisms that reduce the gap between actual and desired workplace characteristics.
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Genomewide analysis of LATERAL ORGAN BOUNDARIES Domain gene family in Zea mays.
J. Genet.
PUBLISHED: 05-21-2014
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The investigation of transcription factor (TF) families is a major focus of postgenomic research. The plant-specific ASYMMETRIC LEAVES2-LIKE (ASL) / LATERAL ORGAN BOUNDARIES Domain (LBD) proteins constitute a major zincfinger-like-domain transcription factor family, and regulate diverse biological processes in plants. However, little is known about LBD genes in maize (Zea mays). In this study, a total of 44 LBD genes were identified in maize genome and were phylogenetically clustered into two groups (I and II), together with LBDs from Arabidopsis. The predicted maize LBDs were distributed across all the 10 chromosomes with different densities. In addition, the gene structures of maize LBDs were analysed. The expression profiles of the maize LBD genes under normal growth conditions were analysed by microarray data and qRT-PCR. The results indicated that LBDs might be involved in various aspects of physiological and developmental processes in maize. To our knowledge, this is the first report of a genomewide analysis of the maize LBD gene family, which would provide valuable information for understanding the classification and putative functions of the gene family.
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Nanostructured carbon materials based electrothermal air pump actuators.
Nanoscale
PUBLISHED: 05-20-2014
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Actuator materials can directly convert different types of energy into mechanical energy. In this work, we designed and fabricated electrothermal air pump-type actuators by utilization of various nanostructured carbon materials, including single wall carbon nanotubes (SWCNTs), reduced graphene oxide (r-GO), and graphene oxide (GO)/SWCNT hybrid films as heating elements to transfer electrical stimulus into thermal energy, and finally convert it into mechanical energy. Both the actuation displacement and working temperature of the actuator films show the monotonically increasing trend with increasing driving voltage within the actuation process. Compared with common polymer nanocomposites based electrothermal actuators, our actuators exhibited better actuation performances with a low driving voltage (<10 V), large generated stress (tens of MPa), high gravimetric density (tens of J kg(-1)), and short response time (few hundreds of milliseconds). Besides that, the pump actuators exhibited excellent stability under cyclic actuation tests. Among these actuators, a relatively larger actuation strain was obtained for the r-GO film actuator due to the intrinsic gas-impermeability nature of graphene platelets. In addition, the high modulus of the r-GO and GO/SWCNT films also guaranteed the large generated stress and high work density. Specifically, the generated stress and gravimetric work density of the GO/SWCNT hybrid film actuator could reach up to more than 50 MPa and 30 J kg(-1), respectively, under a driving voltage of 10 V. The resulting stress value is at least two orders of magnitude higher than that of natural muscles (? 0.4 MPa).
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Improved methods for isolation of avian influenza virus.
J. Virol. Methods
PUBLISHED: 05-13-2014
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Isolation of viruses using chick embryos is a classical virological method. Inoculation of the allantoic cavity and use of allantoic fluid is a common method of passaging isolated avian influenza viruses. In the present study, 2490 fresh fecal samples and 4967 old fecal samples were investigated and subjected to conventional passaging (allantoic fluid method). Two newly developed methods-the allantochorion and allantoic fluid mixed method and the chick embryo and allantoic fluid mixed method-were also examined. The rates of influenza virus isolation for these three methods were compared. There appeared to be little difference among these methods when fresh fecal samples were used. However, for the old fecal samples, isolation rates for influenza virus were significantly higher for the chick embryo and allantoic fluid mixed method compared with the conventional allantoic fluid method. All viruses isolated using the conventional allantoic fluid method were isolated successfully using the two newly developed methods. These results suggest that using chick embryos in conjunction with allantoic fluid is effective for early virus isolation, especially for fecal samples that are not fresh. Additionally, practical chick embryo passage methods are described that improve significantly the rate of isolation of influenza viruses from fecal samples of migratory birds in a complex wild ecological environment.
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Syncytial communication in descending vasa recta includes myoendothelial coupling.
Am. J. Physiol. Renal Physiol.
PUBLISHED: 04-30-2014
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Using dual cell patch-clamp recording, we examined pericyte, endothelial, and myoendothelial cell-to-cell communication in descending vasa recta. Graded current injections into pericytes or endothelia yielded input resistances of 220 ± 21 and 128 ± 20 M?, respectively (P < 0.05). Injection of positive or negative current into an endothelial cell depolarized and hyperpolarized adjacent endothelial cells, respectively. Similarly, current injection into a pericyte depolarized and hyperpolarized adjacent pericytes. During myoendothelial studies, current injection into a pericyte or an endothelial cell yielded small, variable, but significant change of membrane potential in heterologous cells. Membrane potentials of paired pericytes or paired endothelia were highly correlated and identical. Paired measurements of resting potentials in heterologous cells were also correlated, but with slight hyperpolarization of the endothelium relative to the pericyte, -55.2 ± 1.8 vs. -52.9 ± 2.2 mV (P < 0.05). During dual recordings, angiotensin II or bradykinin stimulated temporally identical variations of pericyte and endothelial membrane potential. Similarly, voltage clamp depolarization of pericytes or endothelial cells induced parallel changes of membrane potential in the heterologous cell type. We conclude that the descending vasa recta endothelial syncytium is of lower resistance than the pericyte syncytium and that high-resistance myoendothelial coupling also exists. The myoendothelial communication between pericytes and endothelium maintains near identity of membrane potentials at rest and during agonist stimulation. Finally, endothelia membrane potential lies slightly below pericyte membrane potential, suggesting a tonic role for the former to hyperpolarize the latter and provide a brake on vasoconstriction.
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A two-dimensional homospin Cu(II) ferrimagnet featuring S-shaped hexanuclear secondary building blocks.
Dalton Trans
PUBLISHED: 03-28-2014
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The decomposition of 2-(1-hydroxy-2-methylpropan-2-yl-imino)-1,2-diphenylethanone in the presence of copper acetate promoted the formation of a two-dimensional homospin Cu(II) ferrimagnet featuring S-shaped hexanuclear secondary building blocks and a new pentanodal topology.
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DNA-embedded Au-Ag core-shell nanoparticles assembled on silicon slides as a reliable SERS substrate.
Analyst
PUBLISHED: 03-15-2014
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This study aimed at developing a sensitive and reliable SERS substrate by assembling DNA-embedded Au-Ag core-shell nanoparticles (NPs) on silicon slides. First, a monolayer of well separated DNA-functionalized Au NPs (40 nm) was decorated on (3-aminopropyl)triethoxysilane modified silicon slides. The DNA-embedded Au-Ag core-shell NPs were assembled on the 40 nm Au-DNA NPs to form a core-satellite structure through DNA hybridization. Using 4-MBA as a Raman dye, the SERS performance of the substrates was evaluated after being cleaned by low oxygen and argon plasma. The Raman intensity of the assembly using DNA-embedded Au-Ag core-shell NPs was 8-10 times higher than the intensity of the assembly using Au NPs as satellites. In addition, the signal-to-noise ratio of the assembly was 2.6 times higher than that of a commercial substrate (Klarite™) when a 785 nm laser was used. The SERS enhancements of the assembled substrates were 2.2 to 2.8 times higher than the Klarite when an acquisition time of 5 s was used at an excitation wavelength of 633 nm. The assembled substrates also show a good spot-to-spot and substrate-to-substrate reproducibility at the excitation wavelengths of 633 and 785 nm. These results demonstrate that the fabrication process is simple and cost-effective for assembling DNA-embedded Au-Ag core-shell NPs on silicon slides that can be used as a reliable SERS substrate.
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[Effect of Sini decoction on function of hypothalamic-pituitary-adrenal axis in patients with sepsis].
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue
PUBLISHED: 03-07-2014
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To investigate the effects of Sini decoction on function of hypothalamic-pituitary-adrenal axis in patients with sepsis.
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Novel monodisperse molecularly imprinted shell for estradiol based on surface imprinted hollow vinyl-SiO? particles.
Talanta
PUBLISHED: 02-14-2014
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A novel monodisperse molecularly imprinted shell was prepared based on surface imprinted hollow vinyl-SiO2 particles and applied to selective recognition and adsorption of estradiol (E2). This method was carried out by introducing vinyltriethoxysilane to the surface of polystyrene (PS) spheres by a simple one-step modification, followed by dissolution to remove the PS cores, and then by copolymerization of functional monomers via surface imprinted on the hollow vinyl-SiO2 particles to prepare uniform E2-imprinted shells. Two interesting characteristics were found: first, the obtained hollow molecularly imprinted polymer shells (H-MIPs) had highly monodispersity, uniform spherical shape with a shell thickness of about 40 nm; and then, the method was simple, easy to operate by directing coating of a uniform shell on hollow particles via surface imprinting. The resultant H-MIPs demonstrated improvements in imprinting factor and binding kinetics, owing to the high selectivity to template molecules, surface imprinting technique and hollow porous structure. Furthermore, satisfactory recoveries of 97.0 and 94.8% with respective precisions of 2.5 and 2.7% were achieved by one-step extraction when H-MIPs were used for the preconcentration and selective separation of estradiol in milk samples at two spiked levels. The simple, effective H-MIPs based strategy provided new insights into the formation of various functionalized coating layers on different kinds of support materials with versatile potential applications.
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[Protective effects of pretreatment with neurotrophin-3 on intrathecal ropivacaine in rats].
Zhong Nan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 01-30-2014
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To investigate the effect of pretreatment with neurotrophin-3 (NT-3) on intrathecal ropivacaine in rats.
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Chemodosimeter-based fluorescent detection of L-cysteine after extracted by molecularly imprinted polymers.
Talanta
PUBLISHED: 01-29-2014
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A chemodosimeter-based fluorescent detection method coupled with molecularly imprinted polymers (MIPs) extraction was developed for determination of L-cysteine (L-Cys) by combining molecular imprinting technique with fluorescent chemodosimeter. The MIPs prepared by precipitation polymerization with L-Cys as template, possessed high specific surface area of 145 m(2)/g and good thermal stability without decomposition lower than 300 °C, and were successfully applied as an adsorbent with excellent selectivity for L-Cys over other amino acids, and enantioselectivity was also demonstrated. A novel chemodosimeter, rhodamine B1, was synthesized for discriminating L-Cys from its structurally similar homocysteine and glutathione as well as various possibly co-existing biospecies in aqueous solutions with notable fluorescence enhancement when adding L-Cys. As L-Cys was added with increasing concentrations, an emission band peaked at 580 nm occurred and significantly increased in fluorescence intensity, by which the L-Cys could be sensed optically. High detectability up to 12.5 nM was obtained. An excellent linearity was found within the wide range of 0.05-50 ?M (r=0.9996), and reasonable relative standard deviations ranging from 0.3% to 3.5% were attained. Such typical features as high selectivity, high sensitivity, easy operation and low cost enabled this MIPs-fluorometry to be potentially applicable for routine detection of trace L-Cys.
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Stent-assisted coiling strategies for the treatment of wide-necked basilar artery bifurcation aneurysms.
J Clin Neurosci
PUBLISHED: 01-14-2014
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Stent-assisted coiling is now the preferred treatment option for wide-necked basilar artery bifurcation aneurysms (BABA). However, the optimal choice of specific treatment strategies is still not well documented. In this paper, based on the "two-neck" theory of BABA, we classified the stent-assisted coiling treatment of BABA into three types: unilateral stent-assisted coiling, unilateral stent plus contralateral microcatheter or microwire-assisted coiling, and bilateral stent-assisted coiling. We assessed the feasibility and effectiveness of different stent-assisted coiling strategies for the treatment of BABA. Twenty-three BABA patients treated with stent-assisted coiling between May 2003 and September 2012 were included. Of the 23 aneurysms, 16 were treated with unilateral stent-assisted coiling, two were treated with unilateral stent and microcatheter or microwire-assisted coiling, and five were treated with bilateral stent-assisted coiling. All 23 BABA were successfully embolized, with a technical success rate of 100%. According to the Raymond classification, the immediate procedural outcome was grade I in nine patients, grade II (neck residue) in four patients and grade III (body filling) in 10 patients. The rate of procedure-related complications was 4.3% (1/23), where intra-operative hemorrhage occurred during coiling due to rupture of the aneurysm. Of the 23 patients, 16 (69.6%) had angiographic follow-up. The mean follow-up duration was 13.5 months (range 1-46 months). Angiographic follow-up showed complete occlusion in 10 patients (62.5%), improvement in two patients (12.5%), stability in three patients (18.7%), and recanalization in one patient (6.25%). The various stent-assisted coiling strategies available at present are feasible and effective for the treatment of wide-necked BABA.
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PTEN?, a PTEN isoform translated through alternative initiation, regulates mitochondrial function and energy metabolism.
Cell Metab.
PUBLISHED: 01-07-2014
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PTEN is one of the most frequently mutated genes in human cancer. It is known that PTEN has a wide range of biological functions beyond tumor suppression. Here, we report that PTEN?, an N-terminally extended form of PTEN, functions in mitochondrial metabolism. Translation of PTEN? is initiated from a CUG codon upstream of and in-frame with the coding region of canonical PTEN. Eukaryotic translation initiation factor 2A (eIF2A) controls PTEN? translation, which requires a CUG-centered palindromic motif. We show that PTEN? induces cytochrome c oxidase activity and ATP production in mitochondria. TALEN-mediated somatic deletion of PTEN? impairs mitochondrial respiratory chain function. PTEN? interacts with canonical PTEN to increase PINK1 protein levels and promote energy production. Our studies demonstrate the importance of eIF2A-mediated alternative translation for generation of protein diversity in eukaryotic systems and provide insights into the mechanism by which the PTEN family is involved in multiple cellular processes.
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The HIF-2alpha dependent induction of PAP and adenosine synthesis regulates glioblastoma stem cell function through the A2B adenosine receptor.
Int. J. Biochem. Cell Biol.
PUBLISHED: 01-07-2014
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Glioblastomas are lethal tumors characterized by malignant proliferation and recurrence promoted partly by glioblastoma stem cells (GSCs). GSCs are known to be regulated by hypoxia, but the mechanisms involved in this regulation are not fully understood. We now demonstrate that hypoxia-inducible factor HIF2? and prostatic acid phosphatase (PAP) are preferentially expressed in hypoxic GSCs in comparison with non-stem tumor cells and normal neural stem cells and that PAP is regulated by HIF2?. Targeting PAP in hypoxic GSCs inhibits self-renewal and proliferation in vitro and attenuates tumor initiation potential of GSCs in vivo. Using specific adenosine receptor antagonists, we further find that the pro-proliferative role of PAP is stemmed from stimulated A2B adenosine receptors. Moreover, selective blockage of A2B receptor or knockdown of PAP or A2B on hypoxic GSCs results in significant reduction of phosphorylation of Akt and Erk-1/2. Our results demonstrate that PAP may play a pro-proliferative role in hypoxic GSCs with a HIF2?-induction pattern, which may be ascribed to stimulated A2B receptors and activated Akt and Erk-1/2 pathways. Therefore, we propose that these identified molecular regulators of GSCs in the hypoxic niche might represent promising targets for antiglioblastoma therapies.
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Descending vasa recta endothelial cells and pericytes form mural syncytia.
Am. J. Physiol. Renal Physiol.
PUBLISHED: 01-02-2014
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Using patch clamp, we induced depolarization of descending vasa recta (DVR) pericytes or endothelia and tested whether it was conducted to distant cells. Membrane potential was measured with the fluorescent voltage dye di-8-ANEPPS or with a second patch-clamp electrode. Depolarization of an endothelial cell induced responses in other endothelia within a millisecond and was slowed by gap junction blockade with heptanol. Endothelial response to pericyte depolarization was poor, implying high-resistance myo-endothelial coupling. In contrast, dual patch clamp of neighboring pericytes revealed syncytial coupling. At high sampling rate, the spread of depolarization between pericytes and endothelia occurred in 9 ± 2 or 12 ± 2 ?s, respectively. Heptanol (2 mM) increased the overall input resistance of the pericyte layer to current flow and prevented transmission of depolarization between neighboring cells. The fluorescent tracer Lucifer yellow (LY), when introduced through ruptured patches, spread between neighboring endothelia in 1 to 7 s, depending on location of the flanking cell. LY diffused to endothelial cells on the ipsilateral but not contralateral side of the DVR wall and minimally between pericytes. We conclude that both DVR pericytes and endothelia are part of individual syncytia. The rate of conduction of membrane potential exceeds that for diffusion of hydrophilic molecules by orders of magnitude. Gap junction coupling of adjacent endothelial cells may be spatially oriented to favor longitudinal transmission along the DVR axis.
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Upregulation of ICAM-1 in diabetic rats after transient forebrain ischemia and reperfusion injury.
J Inflamm (Lond)
PUBLISHED: 01-01-2014
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Hyperglycemia exacerbates brain damage caused by cerebral ischemia. Neuroinflammation may play a role in mediating such enhanced damage. The objectives of this study were to examine the mRNA and protein levels and cell type distribution of ICAM-1 after cerebral ischemia in normo-and diabetic hyperglycemic rats.
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Novel Pb(2+) Ion Imprinted Polymers Based on Ionic Interaction via Synergy of Dual Functional Monomers for Selective Solid-Phase Extraction of Pb(2+) in Water Samples.
ACS Appl Mater Interfaces
PUBLISHED: 12-24-2013
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A novel kind of Pb(2+) ion imprinted polymers (IIPs) was prepared based on ionic interactions via the synergy of dual functional monomers of methacrylic acid and vinyl pyridine for selective solid-phase extraction (SPE) of Pb(2+) in water samples. Suspension polymerization was employed for the formation of template Pb(2+)/monomer complex by self-assembly in the presence of ethylene glycol dimethacrylate cross-linker. The resulted Pb(2+) IIPs showed fast kinetics, high binding capacity, and the adsorption processes obeyed intraparticle diffusion kinetics and Langmuir isotherm models. The IIPs displayed excellent selectivity toward Pb(2+) over other metal ions such as Cu(2+), Cd(2+), Zn(2+), and Mn(2+) with selective coefficients above 30, as well as high anti-interference ability for Pb(2+) confronting with common coexisting various ions. Through 10 adsorption-desorption cycles, the reusable IIPs exhibited a good recoverability with the standard error within 5%. These features suggested the IIPs were ideal candidates for extraction and removal of Pb(2+) ions. Consequently, the IIPs were utilized as SPE sorbents and related parameters were optimized. An excellent linearity was presented in the range of 0.2-50 ?g L(-1) (R(2) = 0.9998), as well as the limits of detection and quantification were achieved of 0.06 and 0.19 ?g L(-1), respectively. A good repeatability was obtained with the relative standard deviation of 2.8%. Furthermore, real water samples were successfully analyzed and satisfactory recoveries varying from 95.5 to 104.6% were attained. The IIPs-SPE demonstrated potential application perspectives for rapid and high-effective cleanup and enrichment of trace Pb(2+) ions in complicated matrices.
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[Expression profiling of microRNA and their target genes in peripheral T cell lymphoma, not otherwise specified].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 11-20-2013
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To study the expression profile of microRNAs (miRNAs) in peripheral T cell lymphoma, not otherwise specified (PTCL-NOS) and to explore the underlying molecular characteristics.
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Anti-proliferation effects of interferon-gamma on gastric cancer cells.
Asian Pac. J. Cancer Prev.
PUBLISHED: 11-02-2013
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IFN-? plays an indirect anti-cancer role through the immune system but may have direct negative effects on cancer cells. It regulates the viability of gastric cancer cells, so we examined whether it affects their proliferation and how that might be brought about. We exposed AGS, HGC-27 and GES-1 gastric cancer cell lines to IFN-? and found significantly reduced colony formation ability. Flow cytometry revealed no effect of IFN-? on apoptosis of cell lines and no effect on cell aging as assessed by ?-gal staining. Microarray assay revealed that IFN-? changed the mRNA expression of genes related to the cell cycle and cell proliferation and migration, as well as chemokines and chemokine receptors, and immunity-related genes. Finally, flow cytometry revealed that IFN-? arrested the cells in the G1/S phase. IFN-? may slow proliferation of some gastric cancer cells by affecting the cell cycle to play a negative role in the development of gastric cancer.
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An NBD-armed tetraaza macrocyclic lysosomal-targeted fluorescent probe for imaging copper(II) ions.
Chem. Commun. (Camb.)
PUBLISHED: 10-24-2013
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An NBD-armed tetraaza macrocyclic lysosomal-targeted fluorescent probe for detecting Cu(2+) was synthesized and used for fluorescence imaging in HeLa cells. The probe was specifically localized in lysosomes and successfully applied to visualize Cu(2+) as well as to monitor Cu(2+) level changes in the lysosomes of living cells.
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A hierarchically structured graphene foam and its potential as a large-scale strain-gauge sensor.
Nanoscale
PUBLISHED: 10-22-2013
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A hierarchically structured thermal-reduced graphene (ReG) foam with 0.5 S cm(-1) electrical conductivity is fabricated from a well-dispersed graphene oxide suspension via a directional freezing method followed by high-temperature thermal treatment. The as-prepared three-dimensional ReG foam has an ordered macroporous honeycomb-like structure with straight and parallel voids in the range of 30 ?m to 75 ?m separated by cell walls of several tens of nanometers thick. Despite its ultra-low density, the ReG foam has an excellent compression recovery along its in-plane direction. This property of the ReG foam can be attributed to its hierarchically porous structure, as demonstrated by the compression test. The excellent compression recovery and high conductivity provide the ReG foam with exceptional piezoresistive capabilities. The electrical resistance of the ReG foam shows a linearly decreasing trend with compressive strain increments of up to 60%, which cannot be observed in conventional rigid material-based sensors and carbon nanotube-based polymer sensors. Such intriguing linear strain-responsive behavior, along with the fast response time and high thermal stability, makes the ReG foam a promising candidate for strain sensing. We demonstrated that it could be used as a wearable device for real-time monitoring of human health.
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Effect of emulsified isoflurane on apoptosis of anoxia-reoxygenation neonatal rat cardiomyocytes.
Asian Pac J Trop Med
PUBLISHED: 09-10-2013
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To explore the effect of emulsified isoflurane (EI) on apoptosis of anoxia-reoxygenation neonatal rat cardiomyocytes and relevant protein expression.
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Facile synthesis of Au-Ag core-shell nanoparticles with uniform sub-2.5 nm interior nanogaps.
Chem. Commun. (Camb.)
PUBLISHED: 08-15-2013
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A facile method was established to fabricate uniform nanogaps between a Au core and a Au-Ag alloy shell. The size of nanogaps is controllable due to fast dissolution of AgCl and AgBr in CTAB and the crystal growth of the shell on a designed template. These Au-Ag core-shell nanoparticles with uniform sub-2.5 nm interior nanogaps can be potentially used for various applications.
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[Treatment of comminuted distal tibial fractures with the less invasive stabilization system (LISS)].
Zhongguo Gu Shang
PUBLISHED: 08-14-2013
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To evaluate clinical effects of minimal invasive stabilization system (LISS) for the treatment of comminuted distal tibial fractures.
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[Effects of danshen on NO and ET-1 secreted by endothelial cells induced by the serum of pre-eclampsia patients].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 07-12-2013
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To explore the protective effects of danshen (Salvia Miltiorrhiza) on vascular endothelial cells in hypertension patients in the gestation period.
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[Relationship between XRCC3 gene polymorphism and susceptibility to lead poisoning in male lead-exposed workers].
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
PUBLISHED: 06-28-2013
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To investigate the relationship between genetic polymorphism of X-ray repair cross-complementing gene3 (XRCC3) and susceptibility to lead poisoning in male lead-exposed workers.
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Enhancement of the reflectivity of Al/Zr multilayers by a novel structure.
Opt Express
PUBLISHED: 06-22-2013
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The reflectivity of Al/Zr multilayers is enhanced by the use of a novel structure. The Al layers are divided by insertion of Si layers. In addition, Si barrier layers are inserted at the Al/Zr interfaces (Zr-on-Al and Al-on-Zr). As a result, crystallization of the Al layer is inhibited and that of Zr is enhanced. In grazing incidence x-ray reflectometry, x-ray diffraction, and extreme ultraviolet measurements, the novel multilayers exhibit lower interfacial roughness compared with traditional multilayer structures, and their reflectivity is increased from 48.2% to 50.0% at a 5° angle of incidence. These novel multilayers also have potential applications in other multilayer systems and the semiconductor industry.
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A novel mutation of the KIT gene in a Chinese family with piebaldism.
Chin. Med. J.
PUBLISHED: 06-22-2013
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Human piebaldism is a rare autosomal dominant condition characterized by congenital white forelock and depigmented patches of skin, typically on the forehead, anterior trunk and extremities. Mutations in the KIT gene have been proposed to be responsible for the underlying changes in this disorder. The aim of this study was to identify gene mutation in a Chinese family with piebaldism.
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Mural propagation of descending vasa recta responses to mechanical stimulation.
Am. J. Physiol. Renal Physiol.
PUBLISHED: 05-22-2013
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To investigate the responses of descending vasa recta (DVR) to deformation of the abluminal surface, we devised an automated method that controls duration and frequency of stimulation by utilizing a stream of buffer from a micropipette. During stimulation at one end of the vessel, fluorescent responses from fluo4 or bis[1,3-dibutylbarbituric acid-(5)] trimethineoxonol [DiBAC?(3)], indicating cytoplasmic calcium ([Ca²?]CYT) or membrane potential, respectively, were recorded from distant cells. Alternately, membrane potential was recorded from DVR pericytes by nystatin whole cell patch-clamp. Mechanical stimulation elicited reversible [Ca²?)]CYT responses that increased with frequency. Individual pericyte responses along the vessel were initiated within a fraction of a second of one another. Those responses were inhibited by gap junction blockade with 18 ?-glycyrrhetinic acid (100 ?M) or phosphoinositide 3 kinase inhibition with 2-morpholin-4-yl-8-phenylchromen-4-one (50 ?M). [Ca²?]CYT responses were blocked by removal of extracellular Ca²? or L-type voltage-gated channel blockade with nifedipine (10 ?M). At concentrations selective for the T-type channel blockade, mibefradil (100 nM) was ineffective. During mechanostimulation, pericytes rapidly depolarized, as documented with either DiBAC4(3) fluorescence or patch-clamp recording. Single stimuli yielded depolarizations of 22.5 ± 2.2 mV while repetitive stimuli at 0.1 Hz depolarized pericytes by 44.2 ± 4.0 mV. We conclude that DVR are mechanosensitive and that rapid transmission of signals along the vessel axis requires participation of gap junctions, L-type Ca²? channels, and pericyte depolarization.
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Influence of carbon nanotubes microstructures inside composites on the loading role of nanotubes bore.
J Nanosci Nanotechnol
PUBLISHED: 05-08-2013
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To fully utilize the extraordinary mechanical properties of carbon nanotubes (CNTs) in composites, great attention has been paid to prepare CNTs based composites with uniformly dispersion and strong interfacial adhesion. With the help of micro-Raman spectroscopy, herein, we study the influence of nanotube microstructures (e.g., dispersion and orientation) on the loading role of nanotubes bore. By using the same batch of composite solutions, two types of composite materials with different nanotube morphologies were prepared by electrospun and solution casting methods. Raman results have revealed that the loading-role of nanotubes bore in the electrospun nonwoven mats is much stronger than that of regular composite films owing to its uniformly dispersion as well as high orientation.
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Dielectric properties of carbon nanotubes/epoxy composites.
J Nanosci Nanotechnol
PUBLISHED: 05-08-2013
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Material with high dielectric properties possesses the effect of energy storage and electric field homogenization, which plays an important role in the electrical and electronics domain, especially in the capacitor, electrical machinery and cable realm. In this paper, epoxy-based nanocomposites with high dielectric constant were fabricated by adding pristine and ozone functionalized multi-wall carbon nanotubes (MWCNTs). In the process-related aspect, the favorable technological parameter was obtained via reasonable arrangement and consideration of the dispersing methods including high-speed stirring and three-roller mill. As a result, a uniform dispersion status of MWCNTs in matrix has been guaranteed, which was observed by scanning and transmission electron microscopy. Meanwhile, the influence of different MWCNTs contents and diverse frequencies on the dielectric properties was compared. It was found that the dielectric constant of nano-composites decreased gradually with the increasing of frequency (10(3)-10(6) Hz). Moreover, as the content of MWCNTs increasing, the dielectric constant reached to a maximum of about 1,328 at 10(3) Hz when the pristine MWCNTs content was 0.5 wt.%. Accordingly, the DC conductivity results could interpret the peak value phenomenon by percolation threshold of MWCNTs. In addition, at the fixed content, the dielectric constant of epoxy-based nano-composites with ozone functionalized MWCNTs was lower than that of pristine ones.
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Comparison of the clinical efficacy of temozolomide (TMZ) versus nimustine (ACNU)-based chemotherapy in newly diagnosed glioblastoma.
Neurosurg Rev
PUBLISHED: 05-05-2013
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Although temozolomide (TMZ) replaced nitrosoureas as the standard initial chemotherapy for glioblastoma (GBM), no studies have compared TMZ with nimustine (ACNU), a nitrosourea agent widely used in central Europe and most Asian regions. One hundred thirty-five patients with GBM who underwent extensive tumor resection in our institution received both radiation and chemotherapy as initial treatment, 34 received TMZ and 101 ACNU-based (ACNU plus teniposide or cisplatin) chemotherapy. Efficacy analysis included overall survival (OS) and progression-free survival (PFS). The following prognostic factors were taken into account: age, performance status, extent of resection, and O(6)-methylguanine-DNA-methyltransferase (MGMT) gene status. The median OS was superior in the TMZ versus the ACNU group (p?=?0.011), although MGMT gene silencing, which is associated with a striking survival benefit from alkylating agents, was more frequent in the ACNU group. In multivariate Cox analysis adjusting for the common prognostic factors, TMZ chemotherapy independently predicted a favorable outcome (p?=?0.002 for OS, hazard ratio [HR], 0.45; p?=?0.011 for PFS, HR, 0.56). Given that >40 % of patients in ACNU group did not receive the intensive chemotherapy cycles because of severe hematological and nonhematological toxicity, we performed a further subanalysis for patients who received at least 4 cycles of chemotherapy. Although a modest improvement in survival occurred in this ACNU subgroup, the efficacy was still inferior to that in the TMZ cohort. Our data suggest that the survival benefit of TMZ therapy is superior to that of an ACNU-based regimen in patients with extensive tumor resection, also shows greater tolerability.
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Global Protein Differential Expression Profiling of Cerebrospinal Fluid Samples Pooled from Chinese Sporadic CJD and non-CJD Patients.
Mol. Neurobiol.
PUBLISHED: 05-04-2013
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The shotgun proteomic based on the approach of tandem mass tag (TMT) labeling has received increasing attention for neuroproteomics analysis and becomes an effective tool for the identification and quantification of a large number of proteins for the purpose of revealing key proteins involved in the neuronal dysfunction and an inflammatory response associated with neurodegenerative disorders. To assess the potential expression difference of proteins in cerebrospinal fluids (CSF) between Creutzfeldt-Jakob disease (CJD) and non-CJD patients, the pooled CSF samples from 39 Chinese probable sporadic CJD (sCJD) patients and from 52 non-CJD cases were comparably analyzed with the methodology of TMT labeling and RP-RP-UPLC-MS/MS. Totally, 437 possible proteins were identified in the tested CSF specimen, among them, 49 proteins with 95 % confidence interval. Differential assays showed among those 49 CSF proteins, 12 were upregulated and 13 were downregulated significantly in the sCJD compared to non-CJD. The most affected pathway of the differential expression proteins in CSF of sCJD was complement and coagulation cascade. Western blots for six selected changed proteins in the pooled CSF samples revealed the similar altering profiles in the groups of sCJD and non-CJD as proteomics. Furthermore, CSF samples from 24 CJD patients and 24 non-CJD patients were randomly selected and subjected individually into the Western blots of an increased protein (phosphoglycerate mutase 1) and a decreased one (alpha-1-antichymotrysin), which also confirmed the altering tendency of these identified proteins. Those data indicate that proteomic assay of CSF is a powerful technique not only for selection of the potential biomarkers for the development of diagnostic tool of CJD but also for supplement of useful scientific clues for understanding the CSF homeostasis during the pathogenesis of prion diseases.
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Detection of aflatoxin M1 in milk by dynamic light scattering coupled with superparamagnetic beads and gold nanoprobes.
J. Agric. Food Chem.
PUBLISHED: 05-02-2013
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This study aimed to develop a rapid and sensitive method for detection of aflatoxin M1 (AFM) by dynamic light scattering (DLS) coupled with superparamagnetic beads and gold nanoprobes. The nanoprobes were synthesized by the conjugate of AFM and bovine serum albumin (AFM-BSA), BSA, and gold nanoparticles. Magnetic beads-based immunosorbent assay (MBISA) was used to measure the concentration of AFM by direct competition between AFM and nanoprobes. DLS was used to determine the concentration of unattached nanoprobes that was positively proportional to the concentration of AFM in the sample. TEM images prove that the as-prepared nanoprobes were able to attach on the magnetic beads through the antibody-antigen reaction. Compared to conventional ELISA, MBISA could effectively reduce the incubation time to 15 min in buffer solution and completely eliminate the color development step, thus simplifying the analysis of AFM. A linear relationship was observed between the inhibition values and the concentrations of AFM in both buffer solution (0-1000 ng·L(-1)) and spiked milk samples (0-400 ng·L(-1)). The limit of detection was found to be 37.7 ng·L(-1) for AFM in buffer solution and 27.5 ng·L(-1) in milk samples. These results demonstrate that DLS coupled with magnetic beads and gold nanoprobes is a rapid and effective method to detect AFM. This method could also be easily extended to rapid detection of other mycotoxins and biological species.
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Coupling of chalcocarbonyl ligands (CE: E = S, Se, Te) on an iron carbonyl site: effect of the chalcogen.
Chem. Commun. (Camb.)
PUBLISHED: 04-23-2013
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B3LYP/DZP(Lanl2dz) study of Fe(CO)n(CE)2 (E = S, Se, Te; n = 4, 3) suggests that the Fe(?(2)-E-C) structures are energetically preferred for singlet Fe(CO)4(C2E2) and triplet Fe(CO)3(C2E2). The tendency for coupling reactions of CE ligands to form C2E2 ligands by carbon-carbon bond formation increases in the sequence S < Se < Te.
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Internet usage for health information by patients with epilepsy in China.
Seizure
PUBLISHED: 04-21-2013
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Most patients with epilepsy report a desire for more information on the disease and possible treatments than provided by clinicians. In the past two decades, many have turned to the internet for information, but this information is of variable accuracy and objectivity. We assessed the prevalence of internet use for gathering information about epilepsy and patient satisfaction in a sample of epilepsy patients in China.
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Efficacy of centhaquin as a small volume resuscitative agent in severely hemorrhaged rats.
Am J Emerg Med
PUBLISHED: 04-12-2013
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Centhaquin has been reported to be an effective resuscitative agent. The present study was carried out to determine resuscitative effect of centhaquin when administered using a small volume of 3% hypertonic saline (HS) to hemorrhaged rats. Sprague-Dawley rats were anesthetized with urethane, and a pressure catheter SPR-320 was placed in the left femoral artery; another pressure-volume catheter SPR-869 was placed into the left ventricle. Hemorrhage was induced by withdrawing blood and mean arterial pressure (MAP) was maintained at 35 mm Hg for 30 minutes after which resuscitation was performed. Animals were divided in 2 groups: group A received HS and group B received centhaquin (0.05 mg/kg) dissolved in HS. The time by which MAP fell back to 35 mm Hg was observed at that time all animals were administered fresh blood. It was found that centhaquin significantly reduced blood lactate and improved cardiac output and MAP of hemorrhaged rats compared with HS. The time by which MAP fell back to 35 mm Hg in rats treated with HS was 55 ± 6 minutes, whereas it was 161 ± 14 minutes in centhaquin treated rats. Survival time following administration of fresh blood was 79 ± 7 minutes in vehicle-treated group, whereas it was 105 ± 9 minutes in centhaquin-treated rats. The total time of survival of rats treated with HS or centhaquin was 134 ± 12 minutes and 266 ± 16 minutes, respectively. Centhaquin, in small volume, maintained MAP of hemorrhaged rats for a considerable long time and improved the survival time.
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Activation of receptor for advanced glycation end products contributes to aortic remodeling and endothelial dysfunction in sinoaortic denervated rats.
Atherosclerosis
PUBLISHED: 04-11-2013
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The aim of present study was to test the hypothesis that activation of receptor for advanced glycation end products (RAGE) pathway contributes to aortic remodeling and endothelial dysfunction in sinoaortic denervated (SAD) rats.
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An accurate method for microanalysis of carbon monoxide in putrid postmortem blood by head-space gas chromatography-mass spectrometry (HS/GC/MS).
Forensic Sci. Int.
PUBLISHED: 03-25-2013
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Carbon monoxide (CO) may be the cause of more than half the fatal poisonings reported in many countries, with some of these cases under-reported or misdiagnosed by medical professionals. Therefore, an accurate and reliable analytical method to measure blood carboxyhemoglobin level (COHb%), in the 1% to lethal range, is essential for correct diagnosis. Herein a method was established, i.e. head-space gas chromatography-mass spectrometry (HS/GC/MS) that has numerous advantages over other techniques, such as UV spectrometry, for determination of COHb%. There was a linear relationship (R(2)=0. 9995) between the peak area for CO and the COHb% in blood. Using a molecular sieve-packed column, CO levels in the air down to 0.01% and COHb% levels in small blood samples down to 0.2% could be quantitated rapidly and accurately. Furthermore, this method showed good reproducibility with a relative standard deviation for COHb% of <1%. Therefore, this technique provides an accurate and reliable method for determining CO and COHb% levels and may prove useful for investigation of deaths potentially related to CO exposure.
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Microbial transformation of curcumol by Aspergillus niger.
Nat Prod Commun
PUBLISHED: 03-22-2013
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Curcumol is a representative index component for the quality control of the essential oil of Curcuma wenyujin Y.H. Chen et C. Ling, an antivirus and anticancer drug in China. Microbial transformation of curcumol (1) by Aspergillus niger AS 3.739 yielded two products. Their structures were elucidated as 3alpha-hydroxycurcumol (2) and 3alpha-(4-methoxy-succinyloxy)-curcumol (3) by extensive spectroscopic methods including 2D-NMR and HRESI-MS. Among them, 3 is a new compound. Esterification of the substrate with succinic acid is a novel reaction in the field of microbial transformation of natural products. Compound 2, the major transformation product of 1, was a high regio- and stereo-specific hydroxylation product and showed significant antiviral effects.
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Hepatitis B virus subgenotyping: history, effects of recombination, misclassifications, and corrections.
Infect. Genet. Evol.
PUBLISHED: 03-15-2013
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Hepatitis B virus (HBV) has evolved into phylogenetically separable genotypes and subgenotypes. Accurately assigning the subgenotype for an HBV strain is of clinical and epidemiological significance. In this paper, we review the recommendations currently employed for HBV subgenotyping, the history of HBV subgenotyping, the effects of recombination on HBV subgenotyping, misclassifications in HBV subgenotyping, and suggestions are made to correct the misclassifications. Finally, proposals are made to guide future HBV subgenotyping.
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High mechanical performance of layered graphene oxide/poly(vinyl alcohol) nanocomposite films.
Small
PUBLISHED: 03-14-2013
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The design and fabrication of strong, lightweight, and damage-resistant composite materials are major topics of studies on composites. Biomimetics, a developing multidisciplinary field, is now leading the fabrication of novel materials with remarkable mechanical properties. Graphene oxide (GO), a graphene derivative, possesses good mechanical properties, a high aspect ratio, and good solubility in aqueous solutions, indicating great potential in nanocomposite fields. In this work, bioinspired layered GO/poly(vinyl alcohol) (PVA) nanocomposite films with remarkable mechanical performances are prepared by an environmental friendly, bottom-up assembly methodology. The structural analysis shows alternate piles of inorganic GO platelets and organic PVA binder. Tensile tests indicate that the borate-treated GO/PVA nanocomposite films display 360 MPa of strength, which is twofold to threefold higher than that of biological materials (e.g., nacre). Toughness of GO/PVA nanocomposites is also enhanced fourfold compared with nacre. To reveal the toughening function of the intercalated polymer in the nanocomposites, the influence of polymer with varied molecular weights (Mws) on the fracture mode of the nanocomposites is systematically investigated through quasi-static tensile and creep tests. The PVA molecules with a higher Mw can connect more neighboring GO platelets through inter- and intra-linkages than those with a lower Mw, resulting in efficient stress transfer along the GO plane direction. Thus, tensile strength and toughness are improved. This work illustrates the functions of bonding types between inorganic-organic phases and intercalated polymers with different Mws on the mechanical properties of the layered nanocomposites, including stiffness, strength, and toughness.
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Mini-genome rescue of Crimean-Congo hemorrhagic fever virus and research into the evolutionary patterns of its untranslated regions.
Virus Res.
PUBLISHED: 03-09-2013
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Crimean-Congo hemorrhagic fever virus (CCHFV) is a member of genus Nairovirus, family Bunyaviridae, which are distributed widely in Africa, Europe and Asia with several genotypes. As a BSL-4 level pathogen, the requirement of high-level biosafety facilities severely constrains researches on live virus manipulation. In this study, we developed a helper-virus-independent mini-genome rescue system for the Chinese YL04057 strain. Based on the enhanced green fluorescent protein (EGFP)-derived mini-genome plasmids, this polymerase I driven system permits easy observation and quantification. Unlike previous report, gradually reduced levels of activity of the CCHFV L, M and S untranslated regions (UTRs) were observed in our system. We also demonstrated that the UTRs at both ends were indispensable for mini-genome background expression. In addition, we phylogentically analyzed all six UTRs of CCHFV and showed that L-UTRs were clustered together approximately corresponding to their original geographical continents. The UTRs of M segment showed a similar branch structure to its open reading frames (ORFs), and nearly an identical tree was generated with 5 UTRs of S segment compared with its ORFs. However, the 3 UTRs of S segment formed new divergent groups. Compatibility tests of YL04057 strain nucleocapsid protein and L protein expression plasmids with Nigerian strain IbAr10200 mini-genomes revealed lower compatibility of L-UTRs without an obvious effect on M-UTRs. Moreover, we demonstrated that the L-UTRs could tolerate certain nucleotide mutations. This system may provide a foundation for future studies of the viral replication cycle, pathogenic mechanisms and evolutionary patterns of CCHFV.
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Definitive Radiotherapy for Cervical Esophageal Cancer.
Head Neck
PUBLISHED: 02-21-2013
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Background. The role of contemporary radiotherapy (RT) has not yet been elucidated, mainly because of the low incidence of cervical esophageal cancer. The aim of this study is to analyze the outcome in cervical esophageal cancer patients treated with definitive RT. Patients and methods. A total of 115 patients with cervical esophageal cancer treated with definitive RT during January 2001 through April 2012 in our centre were analyzed. Eighty patients received radiotherapy alone and 35 patients received concurrent chemoradiotherapy with cisplatin administered either weekly (30 mg/m2) or every 3 weeks (80 mg/m2). Results. The median follow-up time was 17.1 months. For all patients, the overall 2-year local failure-free survival, regional failure-free survival, distant failure-free survival, and overall survival rate was 68.3%, 83.3%, 75.7% and 47.6%, respectively. Conclusion. Definitive RT accomplished a satisfactory local control rate and contributed to organ preservation for patients with cervical esophageal cancer. Head Neck, 2013.
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An improved system for the evaluation of antiviral compounds against herpes simplex virus type 2.
J. Virol. Methods
PUBLISHED: 02-06-2013
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Infection with herpes simplex virus type 2 (HSV-2) can result in lesions in reproductive organs, along with long-term latency. In this work, a non-lethal strain of HSV-2 which was isolated clinically was used to infect female mice intravaginally. Body weight, vulval lesions, histological examination of vaginal tissue, and viral load were monitored and used as indices for evaluating antiviral drugs against HSV-2 infection. The results indicated that mice infected with HSV-2 exhibited significant reduction in body weight, serious vulval lesions, massive lymphocyte invasion of vaginal tissue, and approximately 10? copies/?l of HSV-2 were found in vaginal and uterine tissues. Aciclovir (ACV) treatment inhibited loss in body weight, genital pathology and virus replication (reduced to 10?·³ copies/?l) effectively. The study provides a simple, reproducible and feasible animal model for anti-HSV-2 drugs evaluation and HSV-2 vaccine research.
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Clinical characteristics and patterns of failure in the parotid region after intensity-modulated radiotherapy for nasopharyngeal carcinoma.
Oral Oncol.
PUBLISHED: 01-30-2013
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To discuss the clinical characteristics and patterns of failure in the parotid region after intensity-modulated radiotherapy for nasopharygeal carcinoma.
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A pH-responsive nano-carrier with mesoporous silica nanoparticles cores and poly(acrylic acid) shell-layers: fabrication, characterization and properties for controlled release of salidroside.
Int J Pharm
PUBLISHED: 01-30-2013
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A novel pH-responsive nano-carrier MSNs-PAA, possessing mesoporous silica nanoparticles (MSNs) cores and poly(acrylic acid) (PAA) shell-layers, was developed for controlled release of salidroside. The vinyl double bonds modified MSNs were synthesized by using cetyltrimethylammonium bromide (CTAB) as templates, tetraethyl orthosilicate (TEOS) as silicon source, and 3-(trimethoxylsilyl) propyl methacrylate (MPS) as surface modification functionalities. The pH-responsive layers of PAA were grafted onto the vinyl double bonds of the MSNs via precipitation polymerization, producing the MSNs-PAA with a hollow cubic core and mesoporous shell with penetrating pore channels. The characteristic results also showed that PAA was successfully grafted onto the surface of the MSNs. The MSNs-PAA was investigated as carriers for loading and regulating the release of salidroside in different pH solutions for the first time. The results demonstrated that the PAA layers on the surface of MSNs-PAA exhibited opened and closed states at different pH values, and thus could regulate the uptake and release of salidroside. The application of such pH-responsive nano-carrier might offer a potential platform for controlled delivery and increasing the bioavailability of drugs.
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Forensic discrimination of three common brands of kitchen knives in China by ICP-AES and infrared absorption.
Int. J. Legal Med.
PUBLISHED: 01-24-2013
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A block of an injury instrument will be left in wounds sometimes, and the suspect instrument can be discriminated by comparison with the block that was left through elemental analysis. In this study, three brands (Shibazi, Zhangxiaoquan, Qiaoxifu) of kitchen knives with forged, chop, and slice application series were analyzed by inductively coupled plasma atomic emission spectroscopy (ICP-AES) and Infrared Absorption to investigate the type, number of elements and the reference range used for comparing. The results show that when regarding one or more element as the discriminative threshold, together with 5 % relative standard deviation (RSD) as the reference range, all the samples could be distinguished among different series. Furthermore, within the same series, the discriminative capability could reach up to 88.57 % for all samples. In addition, elements with high content, such as Cr, Mn, and C, were useful to discriminate among different series, and trace elements, such as Ni, Si, and Cu, were useful within the same series. However, in practice, it is necessary to evaluate the accuracy of the method by Standard Reference Material (SRM) before an examination is performed.
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Transcriptomic immune response of Tenebrio molitor pupae to parasitization by Scleroderma guani.
PLoS ONE
PUBLISHED: 01-14-2013
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Host and parasitoid interaction is one of the most fascinating relationships of insects, which is currently receiving an increasing interest. Understanding the mechanisms evolved by the parasitoids to evade or suppress the host immune system is important for dissecting this interaction, while it was still poorly known. In order to gain insight into the immune response of Tenebrio molitor to parasitization by Scleroderma guani, the transcriptome of T. molitor pupae was sequenced with focus on immune-related gene, and the non-parasitized and parasitized T. molitor pupae were analyzed by digital gene expression (DGE) analysis with special emphasis on parasitoid-induced immune-related genes using Illumina sequencing.
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Infection and propagation of Crimean-Congo hemorrhagic fever virus in embryonated chicken eggs.
Virus Res.
PUBLISHED: 01-12-2013
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The embryonated chicken egg (ECE) provides a convenient, space-saving incubator for the cultivation of many kinds of animal viruses where the egg can be easily observed for viral replication throughout the development of the chicken embryo. Within the family Bunyaviridae, the embryonated egg has been used as a host system for many viruses such as Rift Valley fever virus and Akabane virus. The current study was conducted to determine the cultivation of Crimean-Congo hemorrhagic fever virus (CCHFV) in ECE. Four-day-old eggs were infected with CCHFV via the yolk sac route and harvested embryonic tissues and amino-allantoic fluid (AAF) that were used for virus passage and viral RNA (vRNA) detection. Quantification of vRNA copies was performed by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Our study indicated that CCHFV caused the death of the embryonated egg in a dose-dependent manner and the 50% egg infectious dose (EID50) was determined to be 6.47×10(5) copies/egg. CCHFV replicated and passaged well in the egg and high viral loads were detected both in embryonic tissue (10(9-10) copies/g) and AAF (10(7-9) copies/ml) of the embryonated egg. Thus, ECE could be used for viral cultivation and preservation, and as a potential host infection model for the study of the pathogenesis of CCHFV.
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Diabetes inhibits cerebral ischemia-induced astrocyte activation - an observation in the cingulate cortex.
Int. J. Biol. Sci.
PUBLISHED: 01-01-2013
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The objective of this study was to study the effect of diabetic hyperglycemia on astrocytes after forebrain ischemia. Streptozotocin (STZ)-injected hyperglycemic and vehicle-injected normoglycemic rats were subjected to 15 minutes of forebrain ischemia. The brains were harvested in sham-operated controls and in animals with 1 and 6 h of recirculation following ischemia. Brain damage was accessed by haematoxylin and eosin (H&E) staining, cleaved caspase-3 immunohistochemistry and TdT-mediated-dUTP nick end labeling (TUNEL). Anti-GFAP antibody was employed to study astrocytes. The results showed that the 15-minute ischemia caused neuronal death after 1 and 6 h of reperfusion as revealed by increased numbers of karyopyknotic cells, edema, TUNEL-positive and active caspase-3-positive cells. Ischemia also activated astrocytes in the cingulated cortex as reflected by astrocyte stomata hypertrophy, elongated dendrites and increases in the number of dendrites, and immunoreactivity of GFAP. Diabetic hyperglycemia further enhanced neuronal death and suppressed ischemia-induced astrocyte activation. Further, diabetes-damaged astrocytes have increased withdrawal of the astrocyte end-foot from the cerebral blood vessel wall. It is concluded that diabetes-induced suppression and damages to astrocytes may contribute to its detrimental effects on recovery from cerebral ischemia.
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Malignant perivascular epithelioid cell tumor of the retroperitoneum.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2013
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Perivascular epithelioid cell tumors (PEComas) are a rare type of mesenchymal neoplasms characterized by a proliferation of perivascular cells with an epithelioid phenotype and expression of myo-melanocytic markers. The majority of PEComas seem to be benign and usually their prognosis is good. Malignant cases are extremely rare, exhibiting a malignant course with local recurrences and distant metastases. We herein report a case of a malignant PEComa arising in the retroperitoneum. The patient was a 55-year-old woman experiencing abdominal discomfort for approximately one month. Ultrasound and computer tomography (CT) scans of the abdomen revealed a solid mass arising from the retroperitoneum. Microscopically, the tumor was composed of epithelioid cells mixed with spindled cells. The nucleus had significant atypia, and the mitoses were obvious. The focal intravascular tumor embolus was visible. Immunohistochemically, the epithelioid tumor cells were positive for HMB45 and Melan-A, and the spindled tumor celLs were positive for SMA and desmin. Seven months after a surgical resection, an ultrasound revealed liver metastases. In conclusion, the malignant PEComas of the retroperitoneum is a very rare neoplasm with unique morphological and immunohistochemical characteristics. It should be differentiated from other epithelioid cell tumors of the retroperitoneum.
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Genome wide analysis of the apple MYB transcription factor family allows the identification of MdoMYB121 gene confering abiotic stress tolerance in plants.
PLoS ONE
PUBLISHED: 01-01-2013
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The MYB proteins comprise one of the largest families of transcription factors (TFs) in plants. Although several MYB genes have been characterized to play roles in secondary metabolism, the MYB family has not yet been identified in apple. In this study, 229 apple MYB genes were identified through a genome-wide analysis and divided into 45 subgroups. A computational analysis was conducted using the apple genomic database to yield a complete overview of the MYB family, including the intron-exon organizations, the sequence features of the MYB DNA-binding domains, the carboxy-terminal motifs, and the chromosomal locations. Subsequently, the expression of 18 MYB genes, including 12 were chosen from stress-related subgroups, while another 6 ones from other subgroups, in response to various abiotic stresses was examined. It was found that several of these MYB genes, particularly MdoMYB121, were induced by multiple stresses. The MdoMYB121 was then further functionally characterized. Its predicted protein was found to be localized in the nucleus. A transgenic analysis indicated that the overexpression of the MdoMYB121 gene remarkably enhanced the tolerance to high salinity, drought, and cold stresses in transgenic tomato and apple plants. Our results indicate that the MYB genes are highly conserved in plant species and that MdoMYB121 can be used as a target gene in genetic engineering approaches to improve the tolerance of plants to multiple abiotic stresses.
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Selective solid-phase extraction of Sudan I in chilli sauce by single-hole hollow molecularly imprinted polymers.
J. Agric. Food Chem.
PUBLISHED: 12-30-2011
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A new single-hole hollow molecularly imprinted polymer (SHH-MIP) was prepared by multistep seed swelling polymerization using Sudan I as template molecule and successfully applied to selective solid-phase extraction (SPE) of Sudan dyes in chilli sauce samples. The polymers possessed high specific surface area obtained by nitrogen adsorption and good thermal stability without decomposition lower than 380 °C by thermogravimetry analysis. Much higher binding capacity was exhibited than with irregular solid MIP prepared by bulk polymerization, because most of the binding sites were located in the surface of the polymers, facilitating template removal and mass transfer. Accordingly, the SHH-MIP was employed as SPE adsorbent for chilli sauce analysis and offered high recoveries for Sudan I in the range of 87.5-103.4% with the precision of 1.94-5.33% at three spiked levels. The SHH-MIP with high selectivity and high stability was demonstrated to be potentially applicable for high selective preconcentration and determination of trace Sudan dyes in complicated samples.
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Expression, enzymatic characterization, and high-level production of glucose isomerase from Actinoplanes missouriensis CICIM B0118(A) in Escherichia coli.
Z. Naturforsch., C, J. Biosci.
PUBLISHED: 12-23-2011
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High-level production of recombinant glucose isomerase (rGI) is desirable for lactulose synthesis. In this study, the xylA gene encoding glucose isomerase from Actinoplanes missouriensis CICIM B0118(A) was cloned and expressed in E. coli BL21(DE3), and high-level production was performed by optimization of the medium composition. rGI was purified from a recombinant E. coli BL21(DE3) and characterized. The optimum pH value of the purified enzyme was 8.0 and it was relatively stable within the pH range of 7.0-9.0. Its optimum temperature was around 85 degrees C, and it exhibited good thermostability when the temperature was lower than 90 degrees C. The maximum enzyme activity required the presence of both Co2+ and Mg2+, at the concentrations of 200 microM and 8 mM, respectively. With high-level expression and the simple one-step chromatographic purification of the His-tagged recombinant enzyme, this GI could be used in industrial production of lactulose as a potential economic tool.
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[The effects of pronase on drugs concentrations for treatment of Helicobacter pylori infection in gastric tissue].
Zhonghua Nei Ke Za Zhi
PUBLISHED: 11-02-2011
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To evaluate the effect of pronase on amoxicillin and metronidazole concentrations in gastric tissue.
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Genetic characteristics of 2009 pandemic H1N1 influenza a viruses isolated from Mainland China.
Virol Sin
PUBLISHED: 10-25-2011
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A total of 100 H1N1 flu real-time-PCR positive throat swabs collected from fever patients in Zhejiang, Hubei and Guangdong between June and November 2009, were provided by local CDC laboratories. After MDCK cell culture, 57 Influenza A Pandemic (H1N1) viruses were isolated and submitted for whole genome sequencing. A total of 39 HA sequences, 52 NA sequences, 36 PB2 sequences, 31 PB1 sequences, 40 PA sequences, 48 NP sequences, 51 MP sequences and 36 NS sequences were obtained, including 20 whole genome sequences. Sequence comparison revealed they shared a high degree of homology (96%-99%) with known epidemic strains (A/California/04/2009(H1N1). Phylogenetic analysis showed that although the sequences were highly conserved, they clustered into a small number of groups with only a few distinct strains. Site analysis revealed three substitutions at loop 220 (221-228) of the HA receptor binding site in the 39 HA sequences: A/Hubei/86/2009 PKVRDQEG ? PKVRDQEA, A/Zhejiang/08/2009 PKVRDQEG ? PKVRDQER, A/Hubei/75/2009 PKVRDQEG ? PKVRDQGG, the A/Hubei/75/2009 was isolated from an acute case, while the other two were from patients with mild symptoms. Other key sites such as 119, 274, 292 and 294 amino acids of NA protein, 627 of PB2 protein were conserved. Meanwhile, all the M2 protein sequences possessed the Ser32Asn mutation, suggesting that these viruses were resistant to adamantanes. Comparison of these sequences with other H1N1 viruses collected from the NCBI database provides insight into H1N1 transmission and circulation patterns.
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1-[2-(1H-Benzimidazol-2-yl)eth-yl]-1H-1,2,3-benzotriazole.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 10-04-2011
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In the title compound, C(15)H(13)N(5), the N-containing heterocycles are linked by an ethyl-ene spacer in a gauche conformation, the N-C-C-C torsion angle along the linker being 60.1?(3)°. The dihedral angle between the terminal benzotriazole and benzimidazole rings is 39.02?(6)°. In the crystal, adjacent mol-ecules are connected by N-H?N hydrogen bonds, forming an infinite chain along the c axis. ?-? stacking inter-actions [centroid-centroid distance = 3.8772?(7)?Å] between the benzotriazole rings of neighbouring chains extend these chains into a supra-molecular sheet in the bc plane. Weak inter-molecular C-H?N inter-actions further stabilize the crystal structure.
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