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Find video protocols related to scientific articles indexed in Pubmed.
Construction of dentate bonded TiO2-CdSe heterostructures with enhanced photoelectrochemical properties: versatile labels toward photoelectrochemical and electrochemical sensing.
Dalton Trans
PUBLISHED: 11-20-2014
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A facile synthetic route for TiO2-CdSe heterostructures was proposed based on dentate binding of TiO2 to carboxyl. Carboxyl functionalized CdSe quantum dots (CF-CdSe QDs) were successfully bonded onto TiO2 nanoparticles (NPs), which could significantly improve the photoelectrochemical (PEC) properties of TiO2 NPs. This is ascribed to the fact that CdSe QDs with a narrow band gap could be stimulated under visible light irradiation, and the energy levels of TiO2 NPs and CF-CdSe QDs are aligned with an electrolyte solution. High resolution transmission electron microscopy images revealed the heterostructures of the TiO2-CdSe composites. Ultraviolet visible spectroscopy, photoluminescence emission spectroscopy and electrochemical impedance spectroscopy analysis exhibited that the prepared TiO2-CdSe heterostructures have improved light absorption, charge separation efficiency and electron transfer ability in the visible light region. TiO2-CdSe heterostructures were used as versatile labels for fabrication of PEC and electrochemical immunosensors, and human immune globulin G (HIgG) was used as a model analyte. The immunosensor showed high sensitivity, a low detection limit and a wide linear range, which could be applied in practical serum sample analysis. The constructed TiO2-CdSe heterostructures would have potential applications in photocatalysis, aptasensors, cytosensors and other areas of nanotechnology.
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SFTS virus infection in non-human primates.
J. Infect. Dis.
PUBLISHED: 10-19-2014
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SFTS virus (SFTSV) is a highly pathogenic bunyavirus that causes severe fever with thrombocytopenia syndrome (SFTS), an emerging infectious disease in China. Laboratory mice have been reported to be susceptible to SFTSV infection, but the infection of SFTSV in non-human primates (NHPs) has not been investigated. This study is the first to report that SFTSV does not cause severe symptoms or death in rhesus macaques, but causes fever, thrombocytopenia, leukocytopenia, as well as raised levels of transaminases and myocardial enzymes in blood. Viremia, virus specific IgM and IgG antibodies, and neutralizing antibodies were identified in all infected macaques. The cytokines interferon-?, eotaxin, TNF-?, and MIP-1? were significantly elevated in the blood. Minor pathological lesions were observed in the liver and kidney in late stages of infection. Overall, SFTSV infection in rhesus macaques resembled a mild SFTS disease in humans.
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Assessment of the internal genes of influenza A (H7N9) virus contributing to the high pathogenicity in mice.
J. Virol.
PUBLISHED: 10-17-2014
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The recently identified H7N9 influenza A virus has caused severe economic losses and worldwide public concern. Genetic analysis indicates that its six internal genes all originated from H9N2 viruses. However, the H7N9 virus is more highly pathogenic in humans than H9N2, which suggests that the internal genes of H7N9 have mutated. To analyze which H7N9 virus internal genes contribute to its high pathogenicity, a series of reassortants were generated by reverse genetics, each containing a single internal gene of the typical A/Anhui/1/2013(H7N9) virus in the genetic background of the A/chicken/Shandong/lx1023/2007(H9N2) virus. Their replication ability, polymerase activity, and pathogenicity were then evaluated in vitro and in vivo. These recombinants displayed high genetic compatibility, and the H7N9-derived PB2, M, and NP genes were identified as the virulence genes for the reassortants in mice. Further investigation confirmed PB2-K627 is critical for the high pathogenicity of the H7N9 virus and the reassortant containing the H7N9-derived PB2 segment (H9N2-AH/PB2). Notably, the H7N9-derived PB2 gene displayed a greater compatibility with the H9N2 genome than that of H7N9, endowing the H9N2-AH/PB2 reassortant with greater viability and virulence than the parental H7N9 virus. In addition, the H7N9 virus, with the exception of the H9N2 reassortants, could effectively replicate in human A549 cells. Our results indicate that PB2, M, and NP are the key virulence genes, together with the surface HA and NA proteins, contributing to the high infectivity of the H7N9 virus in humans.
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Transmission of H7N9 influenza virus in mice by different infective routes.
Virol. J.
PUBLISHED: 10-03-2014
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On 19 February 2013, the first patient infected with a novel influenza A H7N9 virus from an avian source showed symptoms of sickness. More than 349 laboratory-confirmed cases and 109 deaths have been reported in mainland China since then. Laboratory-confirmed, human-to-human H7N9 virus transmission has not been documented between individuals having close contact; however, this transmission route could not be excluded for three families. To control the spread of the avian influenza H7N9 virus, we must better understand its pathogenesis, transmissibility, and transmission routes in mammals. Studies have shown that this particular virus is transmitted by aerosols among ferrets.
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Adiponectin abates atherosclerosis by reducing oxidative stress.
Med. Sci. Monit.
PUBLISHED: 10-03-2014
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We investigated whether the anti-atherosclerosis of adiponectin (APN) relates to the reduction of oxidative stress. We observed the overexpression of adiponectin gene with different titers on atherosclerosis (AS) models of high-fat apolipoprotein E-deficient (ApoE-/-) mice.
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Combinations of Oseltamivir and Fibrates Prolong the Mean Survival Time of Mice Infected with the Lethal H7N9 Influenza Virus.
J. Gen. Virol.
PUBLISHED: 10-03-2014
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The outbreak of human infections caused by the novel avian-origin H7N9 influenza viruses in China since March 2013 underscores the urgent need to find an effective treatment strategy against H7N9 infection in humans. In this study, we assessed the effectiveness of combinations of oseltamivir and two immunomodulators, simvastatin and fenofibrate, against H7N9 infection in a mouse model. Mice treated with oseltamivir plus fenofibrate exhibited the longest mean survival time, the largest reduction of viral titer in lung tissue, the highest levels of CD4+ and CD8+ T lymphocytes, and the greatest decrease in pulmonary inflammation. Thus, the combination of oseltamivir plus fenofibrate improved the outcomes of mice infected with H7N9 virus by simultaneously reducing viral replication and normalizing the aberrant immune response. This drug combination should be considered in randomized controlled trials of treatments for H7N9 patients.
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Inhibition of insect glutathione s-transferase (gst) by conifer extracts.
Arch. Insect Biochem. Physiol.
PUBLISHED: 09-30-2014
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Insecticide synergists biochemically inhibit insect metabolic enzyme activity and are used both to increase the effectiveness of insecticides and as a diagnostic tool for resistance mechanisms. Considerable attention has been focused on identifying new synergists from phytochemicals with recognized biological activities, specifically enzyme inhibition. Jack pine (Pinus banksiana Lamb.), black spruce (Picea mariana (Mill.) BSP.), balsam fir (Abies balsamea (L.) Mill.), and tamarack larch (Larix laricina (Du Roi) Koch) have been used by native Canadians as traditional medicine, specifically for the anti-inflammatory and antioxidant properties based on enzyme inhibitory activity. To identify the potential allelochemicals with synergistic activity, ethanol crude extracts and methanol/water fractions were separated by Sephadex LH-20 chromatographic column and tested for in vitro glutathione S-transferase (GST) inhibition activity using insecticide-resistant Colorado potato beetle, Leptinotarsa decemlineata (Say) midgut and fat-body homogenate. The fractions showing similar activity were combined and analyzed by ultra pressure liquid chromatography-mass spectrometry. A lignan, (+)-lariciresinol 9'-p-coumarate, was identified from P. mariana cone extracts, and L. laricina and A. balsamea bark extracts. A flavonoid, taxifolin, was identified from P. mariana and P. banksiana cone extracts and L. laricina bark extracts. Both compounds inhibit GST activity with taxifolin showing greater activity compared to (+)-lariciresinol 9'-p-coumarate and the standard GST inhibitor, diethyl maleate. The results suggested that these compounds can be considered as potential new insecticide synergists.
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[Hydrophilic interaction chromatography on silica column: retention mechanism and its influential factors].
Se Pu
PUBLISHED: 09-27-2014
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Hydrophilic interaction chromatography (HILIC) is a valuable alternative to reversed phase liquid chromatography (RPLC) for the analysis of highly polar and hydrophilic compounds, in which the separation mechanism is quite different from RPLC and the separation selectivity is complementary to RPLC. This separation mode can be characterized as normal phase liquid chromatography (NPLC) on polar columns in aqueous-organic mobile phases rich in organic solvents (usually acetonitrile). Silica has been the earliest developed and most widely used HILIC stationary phase. This review deals with the recent advances in the development of the retention mechanism on silica column with special attention to the effects of stationary phase, mobile phase composition and temperature on separation in HILIC mode. Moreover, the developing trends and applications of this HILIC mode are presented.
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Age-related differences in factors associated with the underuse of recommended medications in acute coronary syndrome patients at least one year after hospital discharge.
BMC Cardiovasc Disord
PUBLISHED: 09-19-2014
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Few studies have evaluated age-related predictors associated with the underuse of medications in patients with coronary heart disease (CHD). The objective of this study was to identify age-related differences in the factors associated with the underuse of recommended medications in patients diagnosed with acute coronary syndrome (ACS).
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Simultaneous adsorption of SO2 and NO from flue gas over mesoporous alumina.
Environ Technol
PUBLISHED: 09-05-2014
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Mesoporous alumina (MA) with a higher ability to simultaneously remove SO2 and NO was prepared by the evaporation-induced self-assembly process. The adsorption capacities of MA are 1.79 and 0.702?mmol/g for SO2 and NO, respectively. The Brunauer-Emmett-Teller method was used to characterize the adsorbent. Simultaneous adsorption of SO2 and NO from flue gas over MA in different operating conditions had been studied in a fixed bed reactor. The effects of temperature, oxygen concentration and water vapour were investigated. The experimental results showed that the optimum temperature for MA to simultaneously remove SO2 and NO was 90°C. The simultaneous adsorption capacities of SO2 and NO could be enhanced by increasing O2 when its concentration was below 5%. The changes of simultaneous adsorption capacities were not obvious when O2 concentration was above 5%. The increase in relative humidity results in an increase after dropping of SO2 adsorption capacity, whereas the adsorption capacity of NO showed an opposite trend. The results suggest that MA is a great adsorbent for simultaneous removal of SO2 and NO from flue gas.
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Electrochemical immunosensor for ?-fetoprotein detection using ferroferric oxide and horseradish peroxidase as signal amplification labels.
Anal. Biochem.
PUBLISHED: 08-26-2014
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An electrochemical immunosensor for quantitative detection of ?-fetoprotein (AFP) in human serum was developed using graphene sheets (GS) and thionine (TH) as electrode materials and mesoporous silica nanoparticles (MSNs) loaded with ferroferric oxide (Fe3O4) nanoparticles and horseradish peroxidase (HRP) as labels for signal amplification. In this study, the compound of GS and TH (GS-TH) was used as a substrate for promoting electron transfer and immobilization of primary antibody of AFP (Ab1). MSNs were used as a carrier for immobilization of secondary antibody of AFP (Ab2), Fe3O4, and HRP. The synergistic effect occurred between Fe3O4 and HRP and greatly improved the sensitivity of the immunosensor. This method could detect AFP over a wide concentration range from 0.01 to 25ngml(-1) with a detection limit of 4pgml(-1). This strategy may find wide potential application in clinical analysis or detection of other tumor markers.
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Label-free photoelectrochemical immunosensor for sensitive detection of Ochratoxin A.
Biosens Bioelectron
PUBLISHED: 08-19-2014
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A general label-free photoelectrochemical (PEC) platform was manufactured by assembly of CdSe nanoparticles (NPs) sensitized anatase TiO2-functionalized electrode via layer-by-layer (LBL) strategy. CdSe NPs were assembled on anatase TiO2-functionalized electrode through dentate binding of TiO2 NPs to -COOH groups. Ascorbic acid (AA) was used as an efficient electron donor for scavenging photogenerated holes under visible-light irradiation. The photocurrent response of the CdSe NPs modified electrode was significantly enhanced as a result of the band alignment of CdSe and TiO2 in electrolyte. Ochratoxin A (OTA), as model analyte, was employed to investigate the performance of the PEC platform. Antibodies of OTA were immobilized on CdSe sensitized electrode by using the classic 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride coupling reactions between -COOH groups on the surfaces of CdSe NPs and -NH2 groups of the antibody. Under the optimized conditions, the photocurrent was proportional to OTA concentration range from 10pg/mL to 50ng/mL with detection limit of 2.0pg/mL. The employed PEC platform established a simple, fast and inexpensive strategy for fabrication of label-free biosensor, which might be widely applied in bioanalysis and biosensing in the future.
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Preclinical safety evaluation of human mesenchymal stem cell transplantation in cerebrum of nonhuman primates.
Int. J. Toxicol.
PUBLISHED: 08-17-2014
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The efficacy of stem cell transplantation for promoting recovery of patients with neurological diseases, such as stroke, has been reported in several studies. However, the safety of the intracerebral transplantation of human mesenchymal stem cells (hMSCs) remains unclear. The aim of the study was to evaluate the safety of hMSCs transplanted in cerebrum of Macaca fascicularis and to provide evidence for clinical application. A total of 24 M fascicularis were assigned to 3 groups randomly: low dose (3.0 × 10(5) cells/kg), high dose (2.5 × 10(6) cells/kg), and the control (normal saline [NS]). Human mesenchymal stem cells or NS were injected into each monkey for 2 times, with an interval of 3 weeks. The injection point was located outside of the right putamen, according to a stereotactic map and preoperative magnetic resonance imaging of the monkeys. Animal health, behavior, biophysical and biochemical parameters, and brain neurological function were routinely monitored over a 6-month period posttransplantation, and the histopathologic examinations were also performed. The results showed that local pathologic damage including local tissue necrosis and inflammation was induced after the injection. The damage of low-dose and high-dose groups was greater than that of the control group, yet over time, the damage could be repaired gradually. No major hMSCs-associated changes were induced from other indicators, and the transplantation of hMSCs in monkeys did not affect total immunoglobulin (Ig) M, total IgG, CD3, CD4, or CD8 values. We therefore conclude that transplantation of hMSCs to the cerebrum represents a safe alternative for clinical application of neurological disorders.
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Ultrasensitive electrochemical immunoassay for CEA through host-guest interaction of ?-cyclodextrin functionalized graphene and Cu@Ag core-shell nanoparticles with adamantine-modified antibody.
Biosens Bioelectron
PUBLISHED: 08-07-2014
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A novel non-enzymatic immunoassay was designed for ultrasensitive electrochemical detection of carcino-embryonic antigen (CEA) using ?-cyclodextrin functionalized Cu@Ag (Cu@Ag-CD) core-shell nanoparticles as labels and ?-cyclodextrin functionalized graphene nanosheet (CD-GN) as sensor platform. CD-GN has excellent conductivity which promoted the electric transmission between base solution and electrode surface and enhanced sensitivity of immunosensor. In addition, owing to supramolecular recognition of CD-GN for the guest molecule, quite a few synthesized adamantine-modified primary antibodies (ADA-Ab1) were immobilized on the CD-GN by supramolecular host-guest interaction between CD and ADA. Cu@Ag-CD as a signal tag could be captured by ADA-modified secondary antibody (ADA-Ab2) through a host-guest interaction, leading to a large loading of Cu@Ag nanoparticles with high electrical conductivity and catalytic activity. The fabricated immunosensor exhibits excellent analytical performance for the measurement of CEA with wide range linear (0.0001-20 ng/mL), low detection limit (20 fg/mL), good sensitivity, reproducibility and stability, which provide an enormous application prospect in clinical diagnostics.
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Iridium complexes of new NCP pincer ligands: catalytic alkane dehydrogenation and alkene isomerization.
Chem. Commun. (Camb.)
PUBLISHED: 08-07-2014
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Iridium complexes of novel NCP pincer ligands containing pyridine and phosphinite arms have been synthesized. One Ir complex shows good catalytic activity for alkane dehydrogenation, and all complexes are highly active for olefin isomerization. A combination of the Ir complex and a (PNN)Fe pincer complex catalyzes the formation of linear alkylboronates selectively from internal olefins via sequential olefin isomerization-hydroboration.
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PB2-E627K and PA-T97I substitutions enhance polymerase activity and confer a virulent phenotype to an H6N1 avian influenza virus in mice.
Virology
PUBLISHED: 07-25-2014
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H6N1 avian influenza viruses (AIVs) may pose a potential human risk as suggested by the first documented naturally-acquired human H6N1 virus infection in 2013. Here, we set out to elucidate viral determinants critical to the pathogenesis of this virus using a mouse model. We found that the recombinant H6N1 viruses possessing both the PA-T97I and PB2-E627K substitutions displayed the greatest enhancement of replication in vitro and in vivo. Polymerase complexes possessing either PB2-E627K, PA-T97I, and PB2-E627K/PA-T97I displayed higher virus polymerase activity when compared to the wild-type virus, which may account for the increased replication kinetics and enhanced virulence of variant viruses. Our results demonstrate that PB2-E627K and PA-T97I enhance the ability of H6N1 virus to replicate and cause disease in mammals. Influenza surveillance efforts should include scrutiny of these regions of PB2 and PA because of their impact on the increased virulence of H6N1 AIVs in mice.
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Dose of incorporated immunodominant antigen in recombinant BCG impacts modestly on Th1 immune response and protective efficiency against Mycobacterium tuberculosis in mice.
J Immunol Res
PUBLISHED: 07-23-2014
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One approach for improving BCG efficacy is to utilize BCG as vehicle to develop recombinant BCG (rBCG) strains overexpressing Mycobacterium tuberculosis (M. tb) antigens. Also expression level of a candidate antigen should impact the final T cell responses conferred by rBCG. In this study, based on our previously constructed differential expression system, we developed two rBCG strains overexpressing M. tb chimeric antigen Ag856A2 (coding a recombinant ag85a with 2 copies of esat-6 inserted at Acc I site of ag85a) at differential levels under the control of the subtly modified furA promoters. These two rBCG strains were used to vaccinate C57BL/6 mice and exploit dose of incorporated antigen in rBCG to optimize immune response and protective efficiency against M. tb challenge in mouse model. The results showed that rBCG strains overexpressing Ag856A2 at differential levels induced different antigen-specific IFN-? production and comparable number of M. tb-specific CD4 T cells expressing IL-2. M. tb challenge experiment showed that rBCG strains afforded enhanced but comparable immune protection characterized by reduced bacillary load, lung pathology, and inflammation. These results suggested that the dose of antigens incorporated in rBCG can impact T cell immune responses but imposed no significantly differential protective efficacies.
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Antibacterial activity of leaf essential oil and its constituents from Cinnamomum longepaniculatum.
Int J Clin Exp Med
PUBLISHED: 07-15-2014
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Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922 and Salmonella enteritidis CMCC (B) 50041, were used in the antibacterial tests of Cinnamomum longepaniculatum leaf essential oil and its five chemical constituents. The effect of 1, 8-cineole on the ultrastructural structure of the bacteria (S. aureus and E. coli) was also investigated by transmission electron microscopy. The C. longepaniculatum leaf essential oil and the five chemical constituents showed variable levels of inhibition. Their MIC ( minimum inhibitory concentration ) and MBC (minimal bacteriocidal concentration) values were all in the range of 0.781 µL/mL~6.25 µL/mL and 0.781 µL/mL~12.5 µL/mL respectively except ?-terpinene. The MIC values of ?-terpinene against E. coli and S. aureus were all higher than 50 µL/mL, but the MIC and MBC values of ?-terpinene against S. enteritidis was only 3.125 µL/mL. Among them, ?-terpineol possessed the best antibacterial activity. Under the transmission electron microscope, cell size of treated E. coli decreased, cell wall and cell membrane ruptured, and nucleoplasm was reduced and gathered onto the side. After the S. aureus was treated with 1, 8-cineole, the cell size and shape were damaged and nucleus cytoplasm was concentrated or reduced or agglomerated on the side. These results suggest that C. longepaniculatum leaf essential oil and its constituents have excellent antibacterial activities, the antibacterial mechanism of 1, 8-cineole against E. coli and S. aureus might attributable to its hydrophobicity.
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Bone marrow stromal cells protect acute myeloid leukemia cells from anti-CD44 therapy partly through regulating PI3K/Akt-p27(Kip1) axis.
Mol. Carcinog.
PUBLISHED: 07-13-2014
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The anti-CD44 monoclonal antibody (mAb) A3D8 induces differentiation or apoptosis in vitro in various subtypes of acute myeloid leukemia (AML) via p27(Kip1) upregulation. Bone marrow (BM) stromal cells play a vital role in the development of chemoresistance in AML cells attached to the stroma. To investigate the effect of BM stroma adhesion induced AML resistance to A3D8, we developed a co-culture system composed of an AML-derived cell line (NB4) cultured with either a human BM stroma cell line (HS-5) or mesenchymal stem cells (MSCs). We found that NB4 cells adhered to HS-5 cells or MSCs developed resistance against the anti-proliferative effects of A3D8, and this action is caused by the activation of PI3K/Akt signaling following p27(Kip1) down-regulation and cytoplasmic re-localization. The stromal co-culture-induced resistance can be partially abolished by inhibiting the PI3K/Akt signaling pathway. Such findings were confirmed in two additional AML-derived cell lines as well as in primary AML cells. Our results suggest that BM stroma can induce A3D8 resistance in part via the PI3K/Akt-p27(Kip1) axis, and blocking PI3K/Akt pathway maybe necessary for anti-CD44 treatment on AML in BM microenvironment. © 2014 The Authors. Molecular Carcinogenesis published by Wiley Periodicals, Inc.
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Comparison of nitrous oxide emissions in partial nitrifying and full nitrifying granular sludge reactors treating ammonium-rich wastewater.
Bioresour. Technol.
PUBLISHED: 06-19-2014
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The objective of this study was to evaluate the nitrous oxide (N2O) emissions in partial nitrifying and full nitrifying granular sludge reactors treating ammonium-rich wastewater. During stable operation, there was no significant difference of NH4(+)-N removal efficiencies between the two granular reactors. Nitrate and nitrite were the main effluent nitrogen species of the two reactors, and nitrite accumulation rate of partial nitrifying reactor was high of 87.79±2.03%. However, partial nitrifying granular-reactor had better total nitrogen removal efficiency (41.84±3.35%) than that of full nitrifying granular-reactor (19.91±2.12%). According to typical cycles, the N2O emission amount per cycle of partial nitrifying reactor account for 11.48% of the incoming nitrogen load, which was 1.5 times higher than that of full nitrifying reactor (7.47%). The obtained results could provide more information for understanding of N2O emission in granular sludge systems.
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An electrochemical immunosensor for ultrasensitive detection of carbohydrate antigen 199 based on Au@Cu(x)OS yolk-shell nanostructures with porous shells as labels.
Biosens Bioelectron
PUBLISHED: 06-18-2014
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A novel and sensitive electrochemical immunosensor for ultrasensitive detection of pancreatic cancer biomarker carbohydrate antigen 199 (CA199) was proposed by using Au@Cu(x)OS yolk-shell nanostructures with porous shells as labels for signal amplification. Au@Cu(x)OS yolk-shell nanostructures exhibit high electrocatalytic activity toward the reduction of hydrogen peroxide (H2O2) as analytical signal. Moreover, secondary antibody (Ab2) can adsorb on the surface of Au@Cu(x)OS with porous shells which has large surface area and could greatly increase the probability of Ab2-antigen interactions thereby leading to higher sensitivity. Reduced graphene oxide-tetraethylene pentamine (rGO-TEPA), containing abundant amine groups, was supported Au nanoparticles as a support platform to immobilize the primary antibody (Ab1). The resulting sensing interface of rGO-TEPA/AuNPs could provide a large electroconductive surface area, allowing high loadings of the biological recognition elements as well as the occurrence of electrocatalytic and electron-transfer processes. Under optimal conditions, the immunosensor exhibited a wide linear response to CA199 ranging from 0.001 to 12 U/mL with a low detection limit of 0.0005 U/mL. The designed immunosensor displayed good precision, high sensitivity, acceptable stability and reproducibility, and has been applied to the analysis of serum with satisfactory results. The proposed method provides a new promising platform of clinical immunoassay for other biomolecules.
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Valproate improves memory deficits in an Alzheimer's disease mouse model: investigation of possible mechanisms of action.
Cell. Mol. Neurobiol.
PUBLISHED: 06-18-2014
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Alzheimer's disease (AD) is a very common progressive neurodegenerative disorder affecting the learning and memory abilities in the brain. Key findings from recent studies of epigenetic mechanisms of memory suggest chromatin remodeling disorders via histone hypoacetylation of the lysine residue contribute to the cognitive impairment in AD. Therefore, the deinhibition of histone acetylation induced by histone deacetylases (HDACs) inhibitors contributes to recovery of learning and memory. We show here that the antiepileptic drug sodium valproate (VPA) potently enhanced long-term recognition memory and spatial learning and memory in AD transgenic mice. Possible mechanisms showed VPA could significantly elevate histone acetylation through HDACs activity inhibition and increase plasticity-associated gene expression within the hippocampi of mice. Our study suggests that VPA, serving as a HDACs inhibitor, can be considered as a potential pharmaceutical agent for the improvement of cognitive function in AD.
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Facile fabrication of an ultrasensitive sandwich-type electrochemical immunosensor for the quantitative detection of alpha fetoprotein using multifunctional mesoporous silica as platform and label for signal amplification.
Talanta
PUBLISHED: 06-17-2014
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A novel and ultrasensitive sandwich-type electrochemical immunosensor was designed for the quantitative detection of alpha fetoprotein (AFP) using multifunctional mesoporous silica (MCM-41) as platform and label for signal amplification. MCM-41 has high specific surface area, high pore volume, large density of surface silanol groups (SiOH) and good biocompatibility. MCM-41 functionalized with 3-aminopropyltriethoxysilane (APTES), gold nanoparticles (Au NPs) and toluidine blue (TB) could enhance electrochemical signals. Moreover, primary antibodies (Ab1) and secondary antibodies (Ab2) could be effectively immobilized onto the multifunctional MCM-41 by the interaction between Au NPs and amino groups (-NH2) on antibodies. Using multifunctional MCM-41 as a platform and label could greatly simplify the fabrication process and result in a high sensitivity of the designed immunosensor. Under optimal conditions, the designed immunosensor exhibited a wide liner range from 10(-4) ng/mL to 10(3) ng/mL with a low detection limit of 0.05 pg/mL for AFP. The designed immunosensor showed acceptable selectivity, reproducibility and stability, which could provide potential applications in clinical monitoring of AFP.
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A critical care monitoring system for depth of anaesthesia analysis based on entropy analysis and physiological information database.
Australas Phys Eng Sci Med
PUBLISHED: 06-10-2014
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Diagnosis of depth of anaesthesia (DoA) plays an important role in treatment and drug usage in the operating theatre and intensive care unit. With the flourishing development of analysis methods and monitoring devices for DoA, a small amount of physiological data had been stored and shared for further researches. In this paper, a critical care monitoring (CCM) system for DoA monitoring and analysis was designed and developed, which includes two main components: a physiologic information database (PID) and a DoA analysis subsystem. The PID, including biologic data and clinical information was constructed through a browser and server model so as to provide a safe and open platform for storage, sharing and further study of clinical anaesthesia information. In the analysis of DoA, according to our previous studies on approximate entropy, sample entropy (SampEn) and multi-scale entropy (MSE), the SampEn and MSE were integrated into the subsystem for indicating the state of patients underwent surgeries in real time because of their stability. Therefore, this CCM system not only supplies the original biological data and information collected from the operating room, but also shares our studies for improvement and innovation in the research of DoA.
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Characterization of antiproliferative activity constituents from Artocarpus heterophyllus.
J. Agric. Food Chem.
PUBLISHED: 06-04-2014
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Artocarpus heterophyllus is an evergreen fruit tree cultivated in many tropical regions. Previous studies have shown that some of its compositions exhibited potential tyrosinase inhibition activities. This study indentified 8 new phenolic compounds, artoheterophyllins E-J (1-6), 4-geranyl-2',3,4',5-tetrahydroxy-cis-stilbene (7), and 5-methoxymorican M (8) and 2 new natural compounds (9 and 10), 2,3-dihydro-5,7-dihydroxy-2-(2-hydroxy-4-methoxyphenyl)-4H-benzopyran-4-one and 6-[(1S,2S)-1,2-dihydroxy-3-methylbutyl]-2-(2,4-dihydroxyphenyl)-5-hydroxy-7-methoxy-3-(3-methyl-2-buten-1-yl)-4H-1-benzopyran-4-one, together with 23 known compounds (11-33), from the ethanol extract of the wood of A. heterophyllus. The structures of the eight new compounds (1-8) and two new natural compounds were established by extensive 1D- and 2D-NMR experiments. The anticancer effects of the isolated compounds were examined in MCF-7, H460, and SMMC-7721 human cancer cell lines by MTT assay. Compounds 5, 11, 12, and 30 significantly reduced the cell viabilities of these cell lines. Especially, compounds 11 and 30 resulted in more potent cytotoxicity than the positive control, 5-fluorouracil (5-Fu), in SMMC-7721 cell line, with IC50 values of 15.85 and 12.06 ?M, whereas compound 30 exhibited more potent cytotoxicity than 5-Fu in NCI-H460 cell line, with an IC50 value of 5.19 ?M. In addition, this study suggests that compounds 11 and 30 from the wood of A. heterophyllus have anticancer potential via MAPK pathways.
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Tubastatin A/ACY-1215 improves cognition in Alzheimer's disease transgenic mice.
J. Alzheimers Dis.
PUBLISHED: 05-22-2014
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Histone deacetylase 6 (HDAC6) is currently being discussed as a promising therapeutic target for the treatment of Alzheimer's disease (AD). Mounting evidence indicates that increased HDAC6 expression may contribute to AD-associated neurodegeneration, although beneficial effects have also been identified. In the present study, we tested the potential of two selective HDAC6 inhibitors, tubastatin A and ACY-1215, to rescue cognitive deficits in a mouse model of AD. We found that both tubastatin A and ACY-1215 alleviated behavioral deficits, altered amyloid-? (A?) load, and reduced tau hyperphosphorylation in AD mice without obvious adverse effects. Our data suggested that tubastatin A and ACY-1215 not only promoted tubulin acetylation, but also reduced production and facilitated autophagic clearance of A? and hyperphosphorylated tau. Further, the decreased hyperphosphorylated tau and increased tubulin acetylation may account for the improved microtubule stability in AD mice after tubastatin A/ACY-1215 treatment. These preclinical results support the detrimental role of HDAC6 in AD, and offer prospective approaches for using tubastatin A/ACY-1215 as potential therapeutic strategy for AD.
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Ultrasensitive electrochemical immunosensor for carbohydrate antigen 72-4 based on dual signal amplification strategy of nanoporous gold and polyaniline-Au asymmetric multicomponent nanoparticles.
Biosens Bioelectron
PUBLISHED: 05-21-2014
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A sandwich electrochemical immunosensor is described for carbohydrate antigen 72-4 (CA72-4) based on a dual amplification strategy with nanoporous gold (NPG) film as the sensor platform and polyaniline-Au asymmetric multicomponent nanoparticles (PANi-Au AMNPs) as labels. In this study, the second anti-CA72-4 antibody (Ab2) adsorbed onto the Au of the PANi-Au AMNPs, which could be simply synthesized by interfacial reaction and have many characteristics of polyaniline and Au nanoparticle, such as well-controlled size, high conductivity, biocompatibility and catalysis. NPG film was used as electrode substrate material to fix a large number of antibodies, due to its unique properties: good biocompatibility, high conductivity, large surface area, and stability. The synergetic of NPG film and PANi-Au AMNPs could increase signal response, and significantly improve sensitivity of the immunosensor. The proposed immunosensor exhibited a wide linear range from 2 to 200U/mL, with a detection limit of 0.10U/mL CA72-4, good reproducibility, selectivity and stability. This new type of labels for immunosensors may provide many potential applications in the detection of carbohydrate antigen in immunoassays.
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Experimental Mycobacterium tuberculosis infection in the Chinese tree shrew.
FEMS Microbiol. Lett.
PUBLISHED: 05-15-2014
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In recent years, the Chinese tree shrew has been considered to be a promising experimental animal for numerous diseases. Yet the susceptibility of Mycobacterium tuberculosis (MTB) in Chinese tree shrew is still unknown. We infected Chinese tree shrews with a high dose (2.5 × 10(6 ) CFU) or a low dose (2.5 × 10(3 ) CFU) of the H37Rv strain via the femoral vein to cause severe or mild disease. Disease severity was determined by clinical signs, pathologic changes and bacteria distribution in organs. Furthermore, among lung samples of the uninfected, mildly and seriously ill Chinese tree shrews, differentially expressed protein profiles were analyzed through iTRAQ and validated by qPCR. Tuberculous nodules, skin ulceration, pleural effusion and cerebellum necrosis could be observed in seriously ill animals. Regulation of the actin cytoskeleton was newly defined as a possible MTB-related pathway correlated with disease progression. This comprehensive analysis of the experimental infection and the depiction of the proteomics profiles in the Chinese tree shrew provide a foundation for the establishment of a new animal model of tuberculosis and provide a better understanding of the mechanism of tuberculosis.
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Bipolar radiofrequency ablation is useful for treating atrial fibrillation combined with heart valve diseases.
BMC Surg
PUBLISHED: 05-14-2014
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Atrial fibrillation (AF) is a common arrhymia, and it results in increased risk of thromboembolism and decreased cardiac function. In patients undergoing cardiac surgery, concomitant radiofrequency ablation to treat AF is effective in restoring sinus rhythm (SR). This study is an observational cohort study aimed to investigate the safety and efficacy of bipolar radiofrequency ablation (BRFA) for treating AF combined with heart valve diseases.
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[Histopathological changes in EV71-infected mouse model:a transmission electron microscopic study].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 04-19-2014
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To document ultrastructural changes of brain, spinal cord, skeletal muscle, jejunum and lung of EV71 infection mouse model, and to explore the myotropism and pathogenesis of EV71 in nervous system.
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Lowly pathogenic avian influenza (H9N2) infection in Plateau pika (Ochotona curzoniae), Qinghai Lake, China.
Vet. Microbiol.
PUBLISHED: 04-18-2014
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Avian influenza viruses (AIVs) are globally important contagions. Several domestic mammals can be infected with AIVs and may play important roles in the adaptation and transmission of these viruses in mammals, although the roles of wild mammals in the natural ecology of AIVs are not yet clear. Here, we performed a serological survey of apparently healthy Plateau pikas at Qinghai Lake in China to assess the prevalence of exposure to AIVs. Ninety-two of 293 (31%) of wild Plateau pikas possessed serum antibodies against a lowly pathogenic avian influenza (LPAI) H9N2 virus. Experimental inoculation of Plateau pikas with a LPAI H9N2 virus resulted in productive viral replication in respiratory tissues without prior adaptation. Our findings suggest that Plateau pikas represent a natural mammalian host to H9N2 AIVs and may play a role in the ongoing circulation of H9N2 viruses at Qinghai Lake in China. Surveillance for AIV infection in Plateau pika populations and other mammals that have close contact with the Plateau pikas should be considered.
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Distribution of enterovirus 71 RNA in inflammatory cells infiltrating different tissues in fatal cases of hand, foot, and mouth disease.
Arch. Virol.
PUBLISHED: 04-16-2014
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In previous studies of hand, foot, and mouth disease patients fatally infected with enterovirus 71 (EV71), the distribution of viral protein, but not the genome, was determined. To understand the pathogenesis of EV71, however, it is important to investigate the spread of the viral genome. There have been no pathological studies of in situ EV71 viral RNA in inflammatory cells infiltrating various tissues of fatal cases. We therefore first investigated the distribution and classification of inflammatory cells in various tissues and then performed in situ EV71 RNA hybridization in these tissues to better understand the pathogenesis of EV71 infection. EV71 RNA was found mainly in inflammatory cells infiltrating the central nervous system (CNS), intestines, lungs, and tonsils. Most EV71 RNA-positive inflammatory cells in the CNS were macrophages/microglia and neutrophils infiltrating the perivascular cuffing, microglial nodule, neuronophagia, and meninges. CD68+ macrophages and CD15+ neutrophils were diffusely distributed in tissues with severe pathological changes. This study demonstrates the presence of EV71 RNA in inflammatory cells infiltrating tissues in fatally infected patients. Our findings suggest that fatal EV71 infection with extensive infiltration of macrophages/microglia and neutrophils into the CNS results in severe neurological lesions.
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Synthesis of amino functionalized magnetic graphenes composite material and its application to remove Cr(VI), Pb(II), Hg(II), Cd(II) and Ni(II) from contaminated water.
J. Hazard. Mater.
PUBLISHED: 04-11-2014
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In the present study, a kind of graphenes magnetic material (Fe3O4-GS) was prepared by compositing graphene sheet with ferroferric oxide, and shown to be effective for removing Cr(VI), Pb(II), Hg(II), Cd(II) and Ni(II) ions from aqueous solution. The synthesized sorbent was characterized by SEM, TEM, FTIR, XRD, XPS and BET, respectively. The pHZPC value of the sorbent was estimated to be 3.5 by alkaline-titration methods. Fe3O4-GS can be simply recovered from water with magnetic separation at low magnetic field within one minute. The sorption capacities of the metals were 17.29, 27.95, 23.03, 27.83 and 22.07 mg g(-1) for Cr(VI), Pb(II), Hg(II), Cd(II) and Ni(II), respectively. Kinetic data showed good correlation with pseudo-second-order equation and the Freundlich model was found to fit for the isotherm data of all the heavy metal ions. It was found that the metals sorption was accomplished mainly via chelation or ion exchange. The results of thermodynamic studies illustrate that the adsorption process was endothermic and spontaneous in nature.
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Induction of neutralizing antibodies to influenza A virus H7N9 by inactivated whole virus in mice and nonhuman primates.
Antiviral Res.
PUBLISHED: 04-04-2014
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We evaluated the immunogenicity of hemagglutinin (HA) in the context of inactivated H7N9/AH/1/13-PR8 whole-virion. At 4weeks after immunization with 15?g HA, mice produced hemagglutination inhibition (HI) titers of 1:192 and neutralizing antibodies of 1:317. Aluminum hydroxide (alum), or a booster immunization, or both increased HI to 1:768, 1:384, 1:896 and neutralizing antibodies to 1:1868, 1:2302, 1:10,000, respectively. Macaques generated HI of 1:190 or 1:360 and virus neutralizing titers of 1:280 or 1:658 at 3weeks after immunization with HA alone or with alum. Sera from immunized mice and macaques protected mice from infection of A/Anhui/1/2013 (H7N9), suggesting an H7N9 vaccine is immunologically feasible.
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Comparison of viral burden and disease progression in Chinese-origin rhesus macaques infected with common experimentally applied chimeric virus: SHIV-1157ipd3N4, SHIV-162P3, or SHIV-KB9.
J. Med. Primatol.
PUBLISHED: 03-27-2014
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Little is known about the comparative susceptibility and differential pathogenic characteristics of Chinese-origin rhesus macaques upon infection with the chimeric SHIVs most commonly applied in experimental research.
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The distribution of transplanted human mesenchymal stem cells in the CNS of young Macaca fascicularis.
Brain Res.
PUBLISHED: 03-14-2014
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Mesenchymal stem cell (MSC)-based therapies have generated much hope and promise as a potential source of cells for cell-based therapeutic strategies in pediatric degenerative diseases. However, the distribution and migratory routes of MSCs are unknown. Here, real-time PCR and microscopy were used to observe the migration and distribution of labeled human MSCs (hMSCs) transplanted into the striatum of young Macaca fascicularis. Moreover, the differentiation of hMSCs was also detected using immunofluorescence. We found that hMSCs were mainly located near the injection site in the brain and in the anterior brain after 2 weeks. After 4 weeks, the hMSCs had dispersed and could be detected in each brain slice and were more uniformly distributed than after 2 weeks. The hMSCs showed a preference for migration towards blood vessels, which may be one of the migratory routes used by hMSCs. Additionally, hMSCs could be observed to give rise to NeuN- and GFAP-positive cells. Transplanted hMSCs also increased the expression levels of N-cadherin in the host brain tissue, which may be one factor that drives the migration and differentiation of hMSCs after transplantation. These results provide preclinical evidence that MSC-based therapies may represent an efficacious alternative to more conventional treatment regimens for a variety of pediatric neurologic disorders.
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A novel multi-amplification photoelectrochemical immunoassay based on copper(II) enhanced polythiophene sensitized graphitic carbon nitride nanosheet.
Biosens Bioelectron
PUBLISHED: 03-14-2014
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A new sandwich photoelectrochemical (PEC) sensing strategy was proposed for the first time based on the increasing photocurrent of water-soluble polythiophene sensitized g-C3N4 nanosheet (PT-Cl/g-C3N4) in the presence of copper(II) (Cu(2+)), which was doped on the surface of titanium dioxide as labels for multi-amplification. Herein, the photoactive films of PT-Cl/g-C3N4 is employed as the photoactive antibody (Ab1) immobilization matrix for the subsequent sandwich-type antibody-antigen affinity interactions. Upon the presence of antigen (Ag), greatly enhanced photocurrent could be triggered in the PEC platform by the labels of second antibody (Ab2) of Cu(2+) doped titanium dioxide (Cu(2+)-TiO2). As a result of the multi-amplification in this Cu(2+)-TiO2 enhanced PT-Cl/g-C3N4-based PEC immunoassay, it possesses excellent analytical performance. The antigen could be detected from 0.01 pg mL(-1) to 100.0 ng mL(-1) with a detection limit of 5 fg mL(-1). This work opens up g-C3N4 nanosheet applied in PEC sensing. More importantly, the strategy of specific positive effect of Cu(2+) on the photocurrent of g-C3N4 opens an alternative horizon for PEC sensing.
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Antidepressant-like effects and mechanism of action of SYG in depression model in rats.
Neuro Endocrinol. Lett.
PUBLISHED: 03-09-2014
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The present study aimed to evaluate whether SYG, a Chinese herbal formula, could produce antidepressant-like effects in learned helplessness (LH) model and chronic mild stress (CMS) model in rats. The mechanism underlying the antidepressant-like action was investigated by exploring BDNF signaling way in the hippocampus.
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Simultaneous electrochemical immunosensor based on water-soluble polythiophene derivative and functionalized magnetic material.
Anal. Chim. Acta
PUBLISHED: 03-03-2014
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A novel, sensitive electrochemical immunosensor for simultaneous determination of squamous cell carcinoma associated antigen (SCC-Ag) and carcinoembryonic antigen (CEA) for the combined diagnosis of cervical cancer was designed. The amplification strategy for electrochemical immunoassay was based on poly[3-(1,1'-dimethyl-4-piperidine-methylene) thiophene-2,5-diylchloride] (PDPMT-Cl) and functionalized mesoporous ferroferric oxide nanoparticles (Fe3O4 NPs). PDPMT-Cl dispersed in chitosan solution with enhanced electrical conductivity and solubility was used as matrices to immobilize the first antibodies. Different redox probes (thionine (Th) and ferrocenecarboxylic acid (Fca)) functionalized Fe3O4 NPs incubated with two kinds of secondary antibodies to fabricate the labels. Using an electrochemical analysis technique, two well-separated peaks were generated by Th and Fca, making the simultaneous detection of two analytes on the electrode possible. Under optimized conditions, this method showed wide linear ranges of three orders of magnitude with the detection limits of 4 pg mL(-1) and 5 pg mL(-1), respectively. The disposable immunosensor possessed excellent clinical value in cervical cancer screening as well as convenient point-of-care diagnostics.
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The changes of serum sKlotho and NGAL levels and their correlation in type 2 diabetes mellitus patients with different stages of urinary albumin.
Diabetes Res. Clin. Pract.
PUBLISHED: 02-27-2014
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To investigate the changes of serum anti-aging protein Klotho and neutrophil gelatinase-associated lipocalin (NGAL) levels and their correlation in type 2 diabetes mellitus (T2DM) patients at different stages of diabetic kidney disease (DKD) determined by urinary albuminuria.
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Prophylactic and therapeutic effect of AZT/3TC in RT-SHIV infected Chinese-origin rhesus macaques.
AIDS Res Ther
PUBLISHED: 02-26-2014
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The precise efficacy of nucleoside analogue reverse-transcriptase inhibitors (NRTIs) in preventing and inhibiting virus replication remains unknown in RT-SHIV infected Chinese-origin rhesus macaques (Ch RM).
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Preparation of Au-Pt nanostructures by combining top-down with bottom-up strategies and application in label-free electrochemical immunosensor for detection of NMP22.
Bioelectrochemistry
PUBLISHED: 02-20-2014
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A novel label-free amperometric immunosensor for sensitive detection of nuclear matrix protein 22 (NMP22) was developed based on Au-Pt bimetallic nanostructures, which were prepared by combining top-down with bottom-up strategies. Nanoporous gold (NPG) was prepared by "top-down" dealloying of commercial Au/Ag alloy film. After deposition of NPG on an electrode, Pt nanoparticles (PtNPs) were further decorated on NPG by "bottom-up" electrodeposition. The prepared bimetallic nanostructures combine the merits of both NPG and PtNPs, and show a high electrocatalytic activity towards the reduction of H2O2. The label-free immunosensor was constructed by directly immobilizing antibody of NMP22 (anti-NMP22) on the surface of bimetallic nanostructures. The immunoreaction induced amperometric response could be detected and negatively correlated to the concentration of NMP22. Bimetallic nanostructure morphologies and detection conditions were investigated to obtain the best sensing performance. Under the optimal conditions, a linear range from 0.01ng/mL to 10ng/mL and a detection limit of 3.33pg/mL were obtained. The proposed immunosensor showed high sensitivity, good selectivity, stability, reproducibility, and regeneration for the detection of NMP22, and it was evaluated in urine samples, receiving satisfactory results.
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A label-free amperometric immunosensor for detection of zearalenone based on trimetallic Au-core/AgPt-shell nanorattles and mesoporous carbon.
Anal. Chim. Acta
PUBLISHED: 02-19-2014
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A novel label-free amperometric immunosensor is proposed for the ultrasensitive detection of zearalenone (ZEN) based on mesoporous carbon (MC) and trimetallic nanorattles (core/shell particles with movable cores encapsulated in the shells). The nanorattles are composed of special Au-core and imperfect AgPt-shell structure (Au@AgPt). The Au@AgPt nanorattles are loaded onto the MC by physical adsorption. The structure of the Au@AgPt nanorattles was characterized by using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Energy dispersive X-ray spectroscopy (EDS) confirmed the composition of the synthesized nanorattles. Compared with monometallic and bimetallic nanoparticles (NPs), Au@AgPt nanorattles show a higher electron transfer rate due to the synergistic effect of the Au, Ag and Pt NPs. MC further improves the sensitivity of the immunosensor because of its extraordinarily large specific surface area, suitable pore arrangement and outstanding conductivity. The large specific surface area of MC and MC@Au@AgPt were characterized by the BET method. ZEN antibodies are immobilized onto the nanorattles via Ag-NH2 bonds and Pt-NH2 bonds. Cyclic voltammetry and square wave voltammetry were used to characterize the recognizability of ZEN. Under optimum experimental conditions, the proposed immunosensor exhibited a low detection limit (1.7 pg mL(-1)), a wide linear range (from 0.005 to 15 ng mL(-1)) as well as good stability, reproducibility and selectivity. The sensor can be used in clinical analysis.
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IFN?-responsiveness of endothelial cells leads to efficient angiostasis in tumours involving down-regulation of Dll4.
J. Pathol.
PUBLISHED: 02-12-2014
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Although IFN? is regarded as a key cytokine in angiostatic response, our poor understanding of its effective cellular target drastically limits its clinical trials against angiogenesis-related disorders. Here, we investigated the effect of IFN? on endothelial cells (ECs) and possible molecular mechanisms in angiostasis. By employing Tie2(IFN?R) mice, in which IFN?R expression was reconstituted under the control of Tie2 promoter in IFN?R-deficient mice, we found that the response of ECs to IFN? was highly effective in inhibiting blood supply and retarding tumour growth. Interestingly, the expression of IFN?R on Tie2(-) cells did not inhibit, but promoted tumour growth in control wild-type mice. Mechanism studies showed that IFN? reacting on ECs down-regulated the delta-like ligand 4 (Dll4)/Notch signalling pathway. Accordingly, overexpression of Dll4 in human ECs diminished the effect of IFN? on ECs. This study demonstrates that the action of IFN? on ECs, but not other cells, is highly effective for tumour angiostasis, which involves down-regulating Dll4. It provides insights for EC-targeted angiostatic therapy in treating angiogenesis-associated disorders in the clinic.
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Free-space coherent optical communication with orbital angular, momentum multiplexing/demultiplexing using a hybrid 3D photonic integrated circuit.
Opt Express
PUBLISHED: 02-12-2014
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We demonstrate free-space space-division-multiplexing (SDM) with 15 orbital angular momentum (OAM) states using a three-dimensional (3D) photonic integrated circuit (PIC). The hybrid device consists of a silica planar lightwave circuit (PLC) coupled to a 3D waveguide circuit to multiplex/demultiplex OAM states. The low excess loss hybrid device is used in individual and two simultaneous OAM states multiplexing and demultiplexing link experiments with a 20 Gb/s, 1.67 b/s/Hz quadrature phase shift keyed (QPSK) signal, which shows error-free performance for 379,960 tested bits for all OAM states.
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Assessment of the pathogenesis of Streptococcus suis type 2 infection in piglets for understanding streptococcal toxic shock-like syndrome, meningitis, and sequelae.
Vet. Microbiol.
PUBLISHED: 02-08-2014
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Streptococcus suis type 2 (SS2) is an zoonotic pathogen that had caused outbreaks in 1998 and 2005 in China. It is still not very clear how the disease progresses into the streptococcal toxic shock-like syndrome (STSLS) or meningitis, as well as the sequelae from the survivals. The present study used piglets as infection model to systematically investigate the pathogenesis of the infection caused by the SS2 strain 05ZYH33. The infected piglets showed joint swelling, lameness, and crouch at beginning, then developed into septic-like shock syndrome (SLSS) or prostration syndrome, at last the survivals showed physical activity impairment. The morbidity and mortality were 100% (71% for SLSS, 29% for prostration syndrome) and 29%, respectively. The pigs exhibiting SLSS had deep invasive infections in tissues and organs, and displayed more severe bacteremia and cytokine secretion in the bloodstream and organs than pigs with prostration syndrome. Moreover, the polymorphisms in the toll-like receptor 1 (TLR1) and TLR2 genes varied between the pigs affected with SLSS and prostration syndrome. Several lines of evidence indicated that SS2 infection progression into SLSS or relatively lighter prostration syndrome in pigs is closely related to the degrees of bacteremia and cytokine storm, which may be inherently determined by the diversity of innate immunity-associated genes. Furthermore, brain lesions, such as venous thrombosis, may directly contribute to the sequelae in human cases, were identified in the pigs. These results might help us to further understand the pathogenesis of SS2 in humans.
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Rapid adaptation of avian H7N9 virus in pigs.
Virology
PUBLISHED: 01-20-2014
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How the H7N9 avian influenza virus gained the distinct ability to infect humans is unclear. Pigs are an important host in influenza virus ecology because they are susceptible to infection with both avian and human influenza viruses and are often involved in interspecies transmission. Here, we passaged one avian isolate and one human isolate in pigs to examine the mammalian host adaptation of the H7N9 virus. The avian virus replicated to a high titer after one passage, whereas the human isolate replicated poorly after three passages in pig lungs. Sequence analysis found nine substitutions in the HA, NA, M and NS segments of the avian isolate, which enhanced the binding affinity for human-type receptors. These results indicate that avian H7N9 influenza viruses can be easily adapted to pigs and that pigs may act as an important intermediate host for the reassortment and transmission of such novel viruses.
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A simian-human immunodeficiency virus carrying the rt gene from Chinese CRF01_AE strain of HIV is sensitive to nucleoside reverse transcriptase inhibitors and has a highly genetic stability in vivo.
Microbes Infect.
PUBLISHED: 01-16-2014
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Human immunodeficiency virus (HIV)-1 subtype CRF01_AE is one of the major HIV-1 subtypes that dominate the global epidemic. However, its drug resistance, associated mutations, and viral fitness have not been systemically studied, because available chimeric simian-HIVs (SHIVs) usually express the HIV-1 reverse transcriptase (rt) gene of subtype B HIV-1, which is different from subtype CRF01_AE HIV-1. In this study, a recombinant plasmid, pRT-SHIV/AE, was constructed to generate a chimeric RT-SHIV/AE by replacing the rt gene of simian immunodeficiency virus (SIVmac239) with the counterpart of Chinese HIV-1 subtype CRF01_AE. The infectivity, replication capacity, co-receptor tropism, drug sensitivity, and genetic stability of RT-SHIV/AE were characterized. The new chimeric RT-SHIV/AE effectively infected and replicated in human T cell line and rhesus peripheral blood mononuclear cells (rhPBMC). The rt gene of RT-SHIV/AE lacked the common mutation (T215I) associated with drug resistance. RT-SHIV-AE retained infectivity and immunogenicity, similar to that of its counterpart RT-SHIV/TC virus following intravenous inoculation in Chinese rhesus macaque. RT-SHIV-AE was more sensitive to nucleoside reverse transcriptase inhibitors (NRTIs) than the RT-SHIV/TC. RT-SHIV/AE was genetically stable in Chinese rhesus macaque. The new chimeric RT-SHIV/AE may be a valuable tool for evaluating the efficacy of the rt-based antiviral drugs against the subtype CRF01_AE HIV-1.
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Erythropoietin enhances mitochondrial biogenesis in cardiomyocytes exposed to chronic hypoxia through Akt/eNOS signalling pathway.
Cell Biol. Int.
PUBLISHED: 01-16-2014
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Adaptation of cardiomyocytes to chronic hypoxia in cyanotic patients remains unclear. Mitochondrial biogenesis is enhanced in myocardium from cyanotic patients, which is possibly an adaptive response. Erythropoietin (EPO) in blood and its receptor (EPOR) on cardiomyocytes are upregulated by chronic hypoxia, suggesting that EPO-EPOR interaction is increased, which is inferred to positively regulate mitochondrial biogenesis through protein kinase B (Akt)/endothelial nitric oxide synthase (eNOS) signalling pathway. H9c2 cardiomyocytes were exposed to hypoxia (1% O(2)) for 1 week and treated with different doses of recombinant human erythropoietin (rhEPO). Mitochondrial number, mitochondrial DNA (mtDNA) copy number and peroxisome proliferator activated receptor gamma coactivator alpha (PGC-1?) mRNA expression increased in a dose-dependent manner induced by rhEPO. Akt and eNOS were significantly phosphorylated by rhEPO. Both blocking Akt with Wortmannin and silencing eNOS expression with shRNA plasmid decreased the mtDNA copy number and PGC-1? mRNA expression induced by rhEPO. Blocking Akt was associated with the decreased phosphorylation of Akt and eNOS. RNA interference led to a reduction in the total and phosphorylated proteins of eNOS. Thus EPO enhances mitochondrial biogenesis in cardiomyocytes exposed to chronic hypoxia, at least partly through Akt/eNOS signalling, which might be an adaptive mechanism of cardiomyocytes associated with the increased EPO-EPOR interaction in patients with cyanotic congenital heart disease (CCHD).
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Cathodic electrochemiluminescence immunosensor based on nanocomposites of semiconductor carboxylated g-C3N4 and graphene for the ultrasensitive detection of squamous cell carcinoma antigen.
Biosens Bioelectron
PUBLISHED: 01-14-2014
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A novel label-free electrochemiluminescence (ECL) immunosensor was developed for the detection of squamous cell carcinoma antigen (SCCA) based on nanocomposites of semiconductor carboxylated graphitic carbon nitride (g-C3N4) and graphene (g-C3N4-graphene). The ECL intensity of carboxylated g-C3N4 was much enhanced after being combined with graphene which had excellent electron-transfer ability. The sensing platform was constructed by depositing g-C3N4-graphene on electrodes and immobilizing antibodies on the surface of carboxylated g-C3N4 through amidation. The specific immunoreaction between SCCA and antibody resulted in the decrease of ECL intensity and the intensity decreased linearly with the logarithm of SCCA concentration in the range of 0.025-10 ng mL(-1) with a detection limit of 8.53 pg mL(-1). The developed ECL immunosensor exhibited high sensitivity, good reproducibility and long-term stability, which possessed great potential for cancer detection in clinical laboratory diagnosis.
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Histopathological features and distribution of EV71 antigens and SCARB2 in human fatal cases and a mouse model of enterovirus 71 infection.
Virus Res.
PUBLISHED: 01-12-2014
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Enterovirus 71 (EV71) is a neurotropic pathogen that causes hand, foot, and mouth disease. While infection is usually self-limiting, a minority of patients infected with EV71 develop severe neurological complications. In humans, EV71 has been reported to utilize the scavenger receptor class B, member 2 (SCARB2) as a receptor for infectious cellular entry. In this study, we define the pathological features of EV71-associated disease as well as the distribution of EV71 antigen and SCARB2 in human fatal cases and a mouse model. Histopathologically, human fatal cases showed severe central nervous system (CNS) changes, mainly in the brainstems, spinal cords, and thalamus. These patient further exhibited pulmonary edema and necrotic enteritis. Immunohistochemical analysis of human fatal cases demonstrated that EV71 antigen and SCARB2 were observed mainly in neurons, microglia cells and inflammatory cells in the CNS, and epithelial cells in the intestines. However, skeletal muscle tissue was negative for EV71 antigen. In a mouse model of EV71 infection, we observed massive necrotic myositis, different degrees of viral diseases in CNS, and extensive interstitial pneumonia. In mice, EV71 exhibits strong myotropism compared to the neurotropism seen in humans. EV71 antigen was detected in the spinal cord and brainstem of mice. However, there was no clear correlation between mouse SCARB2 and EV71 antigen distribution in the mouse model, consistent with previous results that SCARB2 functions as a receptor for EV71 in humans but not mice. The EV71-induced lesions seen in the mouse model resembled the pathological changes seen in human samples. These results increase our understanding of EV71 pathogenesis and will inform further work developing a mouse model for EV71 infection.
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Decreased expression of lncRNA GAS5 predicts a poor prognosis in cervical cancer.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Cervical cancer is the second leading cause of cancer morbidity and mortality for women around the world. Long non-coding RNAs (lncRNAs) have been investigated as a new class of regulators of cellular processes, such as cell growth, apoptosis, and carcinogenesis. Although downregulation of lncRNA GAS5 in several cancers has been studied, its role in cervical cancer remains unknown. The aim of this study is to investigate the expression, clinical significance and biological role in cervical cancer.
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?-terpineol inhibits cell growth and induces apoptosis in human liver cancer BEL-7402 cells in vitro.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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To investigate the effect of ?-terpineol on cell proliferation and apoptosis of human hepatoma BEL-7402 cells to elucidate its molecular mechanism. Here, BEL-7402 cells were treated with various concentrations (40, 80, 160, 320 and 640 ?g/ml) of ?-terpineol for 48 h, cell proliferation was determined by 3-(4,5-dimethyl-thiazolyl-2)-2,5-diphenyl tetrazolium bromides (MTT) assay. Cell colony inhibition was determined by soft agar assay. Apoptosis and possible molecular mechanisms were evaluated by morphological observation, flow cytometry analysis, and DNA fragmentation assay. The ?-terpineol significantly suppressed BEL-7402 cell proliferation in a dose-dependent manner. Characteristic morphological and biochemical changes associated with apoptosis such as cells shrinkage, deformation and vacuolization of mitochondria, nuclear chromatin condensation and fragmentation, formation of apoptotic bodies were observed after BEL-7402 cells treated with ?-terpineol for 24 h and 48 h. Cell cycle were displayed by flow cytometry analysis, the ?-terpineol treatment resulted in accumulation of cells at G1 or S phase and a blockade of cell proliferation compared to control group. Treating BEL-7402 cells with 320 ?g/ml of ?-terpineol for 36 h and 48 h, a typical apoptotic "DNA ladder" was observed using DNA fragmentation assay. The present study demonstrated that possible anti-cancer mechanism of ?-terpineol on human hematomas cells is through inducing cell apoptosis to suppress tumor cell growth.
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Emergent endovascular vs. open surgery repair for ruptured abdominal aortic aneurysms: a meta-analysis.
PLoS ONE
PUBLISHED: 01-01-2014
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To systematically review studies comparing peri-operative mortality and length of hospital stay in patients with ruptured abdominal aortic aneurysms (rAAAs) who underwent endovascular aneurysm repair (EVAR) to patients who underwent open surgical repair (OSR).
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Early Effect of Essential Hypertension on the Left Ventricular Twist-Displacement Loop by Two-Dimensional Ultrasound Speckle Tracking Imaging.
Echocardiography
PUBLISHED: 12-05-2013
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To investigate two-dimensional (2D) ultrasound speckle tracking imaging (STI) in the evaluation of the early changes in the left ventricular (LV) twist-displacement loop in patients with hypertension (EH).
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Intranasal Immunization of Mice with Inactivated Virus and Mast Cell Activator C48/80 Elicits Protective Immunity against Influenza H1 but not H5.
Immunol. Invest.
PUBLISHED: 12-02-2013
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Vaccination represents the most economic and effective strategy of preventing influenza pandemics. We previously demonstrated that intranasal immunization of mice with recombinant hemagglutinin and the mast cell activator C48/80 elicited protective immunity against challenge with the 2009 pandemic H1N1 influenza in mice, demonstrating that the novel C48/80 mucosal adjuvant was safe and effective. The present study demonstrated that intranasal immunization with inactivated H1N1 virus and C48/80 elicited protective immunity against lethal challenge with homologous virus, however, when the immunogen was replaced with inactivated H5N1 virus protection was lost. These observations suggested that the adjuvant effects conferred by C48/80 were virus subtype specific and that its use as a broad-spectrum adjuvant for use in immunizations against all influenza viruses needs to be further analyzed.
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Development of a novel water-soluble magnetic fluorescent nanoparticle for the selective detection and removal of Cu(2+).
Nanotechnology
PUBLISHED: 11-14-2013
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Recently, much attention has been paid to the selective detection and removal of Cu(2+) because an excess of Cu(2+) can harm the environment and living systems. Herein, we developed a novel water-soluble di-2-picolylamine/proline co-modified Fe3O4@ZnS magnetic fluorescent nanoparticle (MFNP-Cu) for the selective detection and removal of Cu(2+) through a dithiocarbamate linkage strategy. The characterization of MFNP-Cu was confirmed by x-ray diffraction (XRD), transmission electron microscope (TEM), magnetization hysteresis loops, infrared (IR) and emission spectra. The results showed that MFNP-Cu could quantifiably detect Cu(2+) with high sensitivity and selectivity over a broad pH range (pH 4.1-9). The maximum adsorption capacity of MFNP-Cu was calculated to be about 517.9 mg g(-1), which is higher than previously reported. This excellent property was investigated by kinetics equilibrium and thermodynamic studies. Moreover, the removal properties of MFNP-Cu toward Cu(2+) from contaminated water samples was achieved by an external magnetic field.
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The application of on-pump beating-heart surgery for partial atrioventricular septal defect: a report of 87 cases.
Heart Surg Forum
PUBLISHED: 11-13-2013
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Partial atrioventricular septal defect (P-AVSD) is a common congenital heart disease. Because of the presence of left and right atrioventricular valve deformities and the shift in the atrioventricular node and cardiac conduction bundle, the surgical repair of P-AVSD is difficult. This study was performed to compare the effects on the coronary sinus septum in the left versus the right atrium during surgical treatment for P-AVSD and report our experiences regarding the application of on-pump beating heart surgery under mild hypothermia for patients with P-AVSD.
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An Animal Model of MERS Produced by Infection of Rhesus Macaques With MERS Coronavirus.
J. Infect. Dis.
PUBLISHED: 11-11-2013
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In 2012, a novel coronavirus (CoV) associated with severe respiratory disease, Middle East respiratory syndrome (MERS-CoV; previously known as human coronavirus-Erasmus Medical Center or hCoV-EMC), emerged in the Arabian Peninsula. To date, 114 human cases of MERS-CoV have been reported, with 54 fatalities. Animal models for MERS-CoV infection of humans are needed to elucidate MERS pathogenesis and to develop vaccines and antivirals. In this study, we developed rhesus macaques as a model for MERS-CoV using intratracheal inoculation. The infected monkeys showed clinical signs of disease, virus replication, histological lesions, and neutralizing antibody production, indicating that this monkey model is suitable for studies of MERS-CoV infection.
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Liver cancer-related gene CYP2E1 expression in HBV transgenic mice with acute liver injury.
Tumour Biol.
PUBLISHED: 10-28-2013
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The objective of this research was to study the CYP2E1 gene expression in carbon tetrachloride (CCl4)-induced acute liver injury in hepatitis B virus (HBV) transgenic mice. Twenty-four HBV (-) and 24 HBV (+) transgenic mice aged 8 to 10 weeks were selected for the present study. Intraperitoneal injection of 1.0 ?L/g of CCl4 (1:4 dissolved in olive oil) to mice was performed to induce acute liver injury model. Eight normal clean-grade C57BL/6 mice were taken as the control group. The control group received saline intraperitoneally. The mice in each group were killed 3, 6, 12, 24, 48, and 72 h after injection. The liver tissue samples of mice were collected. The liver histological changes at different time points in each group were observed under light microscope. The quantitative PCR methods were utilized to measure the relative mRNA levels of CYP2E1 gene in liver tissues. Immunohistochemistry and Western blot techniques were used to observe tissue expression levels of CYP2E1 in each group. Compared with that of the control group, mRNA and protein expression levels of CYP2E1 significantly increased both in the HBV (-) group and in the HBV (+) group after the CCl4 induced the acute liver injury, and it reached the peak at 72 h after the CCl4 injection. Compared with the HBV (-) group, the mice in the HBV (+) group had severe liver damage and significantly increased CYP2E1 gene and protein expression levels. In the CCl4-induced acute liver injury of HBV transgenic mice, the CYP2E1 gene expression significantly increased. The results provided evidence for the HBV-induced liver damage and liver cancer pathogenesis.
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Antidepressant-like effects and memory enhancement of a herbal formula in mice exposed to chronic mild stress.
Neurosci Bull
PUBLISHED: 10-16-2013
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Shen Yuan Gan (SYG) is a Chinese herbal prescription composed of total saponins of Panax ginseng and total oligosaccharide esters of Polygala tenuifolia (2:1). Our previous studies have demonstrated that SYG has antidepressant-like effects in various mouse models of behavioral depression. The present study aimed to test whether SYG affected chronic mild stress (CMS)-induced depression and cognitive impairment in mice. We found that a 5-week CMS schedule induced significant degradation of the coat state, decreased sucrose intake in the sucrose-preference test, and increased the latency to feed in the noveltysuppressed feeding test. All of these CMS-induced changes were ameliorated by SYG (100 and 200 mg/kg) and fluoxetine (10 mg/kg). In addition, SYG restored the decreased monoamine neurotransmitter concentrations (serotonin, dopamine, norepinephrine and acetylcholine) induced by CMS in the prefrontal cortex. Interestingly, SYG ameliorated CMS-induced cognitive impairment in the step-through test, and increased the acetylcholine level in the prefrontal cortex. These results suggest that SYG has an antidepressant-like action and enhances cognition by modulating the serotonin, dopamine, norepinephrine, and acetylcholine levels in the prefrontal cortex.
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Antigenicity and transmissibility of a novel clade 2.3.2.1 avian influenza H5N1 virus.
J. Gen. Virol.
PUBLISHED: 09-28-2013
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A genetic variant of the H5N1 influenza virus, termed subclade 2.3.2.1, was first identified in Bulgaria in 2010 and has subsequently been found in Vietnam and Laos. Several cases of human infections with this virus have been identified. Thus, it is important to understand the antigenic properties and transmissibility of this variant. Our results showed that, although it is phylogenetically closely related to other previously characterized clade 2.3 viruses, this novel 2.3.2.1 variant exhibited distinct antigenic properties and showed little cross-reactivity to sera raised against other H5N1 viruses. Like other H5N1 viruses, this variant bound preferentially to avian-type receptors, but contained substitutions at positions 190 and 158 of the haemagglutinin (HA) protein that have been postulated to facilitate HA binding to human-type receptors and to enhance viral transmissibility among mammals, respectively. However, this virus did not appear to have acquired the capacity for airborne transmission between ferrets. These findings highlight the challenges in selecting vaccine candidates for H5N1 influenza because these viruses continue to evolve rapidly in the field. It is important to note that some variants have obtained mutations that may gain transmissibility between model animals, and close surveillance of H5N1 viruses in poultry is warranted.
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[Experimental study on co-culture of human fibroblasts on decellularized Achilles tendon].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 09-26-2013
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To investigate the preparation of decellularized Achilles tendons and the effect of co-culture of human fibroblasts on the scaffold so as to provide a scaffold for the tissue engineered ligament reconstruction.
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Identification and characterization of porcine kobuvirus variant isolated from suckling piglet in Gansu province, China.
Viruses
PUBLISHED: 09-19-2013
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Kobuviruses comprise three species, the Aichivirus A, Aichivirus B, and Aichivirus C (porcine kobuvirus). Porcine kobuvirus is endemic to pig farms and is not restricted geographically but, rather, is distributed worldwide. The complete genomic sequences of four porcine kobuvirus strains isolated during a diarrhea outbreak in piglets in the Gansu province of China were determined. Two of these strains exhibited variations relative to the traditional strains. The potential 3C/3D cleavage sites of the variant strains were Q/C, which differed from the Q/S in the traditional porcine kobuvirus genome. A 90-nucleotide deletion in the 2B protein and a single nucleotide insertion in the 3UTR were found in the variant strains. The VP1 regions of all four porcine kobuviruses in our study were highly variable (81%-86%). Ten common amino acid mutations were found specifically at certain positions within the VP1 region. Significant recombination sites were identified using SimPlot scans of whole genome sequences. Porcine kobuviruses were also detected in pig serum, indicating that the virus can escape the gastrointestinal tract and travel to the circulatory system. These findings suggest that mutations and recombination events may have contributed to the high level of genetic diversity of porcine kobuviruses and serve as a driving force in its evolution.
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Comparative analysis of curative effect of CT-guided stem cell transplantation and open surgical transplantation for sequelae of spinal cord injury.
J Transl Med
PUBLISHED: 09-15-2013
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This study compared the clinical efficacies, advantages and disadvantages of two transplantation approaches for treating spinal cord injury: open surgical exploration combined with local stem cell transplantation (referred to as open surgical transplantation) and local stem cell transplantation by CT-guided puncture (referred to as CT-guided transplantation).
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Novel Avian-Origin Human Influenza A(H7N9) Can Be Transmitted Between Ferrets via Respiratory Droplets.
J. Infect. Dis.
PUBLISHED: 08-29-2013
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The outbreak of human infections caused by novel avian-origin influenza A(H7N9) in China since March 2013 underscores the need to better understand the pathogenicity and transmissibility of these viruses in mammals. In a ferret model, the pathogenicity of influenza A(H7N9) was found to be less than that of an influenza A(H5N1) strain but comparable to that of 2009 pandemic influenza A(H1N1), based on the clinical signs, mortality, virus dissemination, and results of histopathologic analyses. Influenza A(H7N9) could replicate in the upper and lower respiratory tract, the heart, the liver, and the olfactory bulb. It is worth noting that influenza A(H7N9) exhibited a low level of transmission between ferrets via respiratory droplets. There were 4 mutations in the virus isolated from the contact ferret: D678Y in the gene encoding PB2, R157K in the gene encoding hemagglutinin (H3 numbering), I109T in the gene encoding nucleoprotein, and T10I in the gene encoding neuraminidase. These data emphasized that avian-origin influenza A(H7N9) can be transmitted between mammals, highlighting its potential for human-to-human transmissibility.
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Simultaneous electrochemical detection of cervical cancer markers using reduced graphene oxide-tetraethylene pentamine as electrode materials and distinguishable redox probes as labels.
Biosens Bioelectron
PUBLISHED: 08-27-2013
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A novel, highly sensitive electrochemical immunoassay was proposed for the simultaneous determination of carcinoembryonic antigen (CEA) and squamous cell carcinoma antigen (SCCA) for the diagnosis of cervical cancer. Using an electrochemical analysis technique, two well-separated peaks were generated by neutral red and thionine, making the simultaneous detection of the two analytes on the electrode possible. Reduced graphene oxide-tetraethylene pentamine (rGO-TEPA), containing more amino groups, was of benefit to immobilize the primary antibody (Ab1) through an amidation reaction. Au@mesoporous carbon CMK-3 was synthesized and incubated with two secondary antibodies (Ab2) and different redox probes (neutral red and thionine) to fabricate the electrochemical immunosensor label intending to improve the analytical performance of the immunosensor. The immunosensor was prepared with a sandwich structure based on the peak current change of neutral red and thionine before and after the antigen-antibody reaction. The results showed that the immunosensor had a wide linear range, low detection limit, good reproducibility and stability. The method has been applied to the analysis of serum samples with satisfactory results.
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Label-free immunosensor based on Pd nanoplates for amperometric immunoassay of alpha-fetoprotein.
Biosens Bioelectron
PUBLISHED: 07-07-2013
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In this paper, Pd nanoplates were used as a kind of electrode materials for fabrication of an electrochemical immunosensor, which was applied for detection of cancer biomarker alpha-fetoprotein (AFP). Thanks to the unique structure and properties of Pd nanoplates, the antibody of AFP (Ab) was effectively immobilized onto the surface of the Pd nanoplates modified glassy carbon electrode (GCE). Moreover, the good electrochemical properties of Pd nanoplates greatly improved the electronic transmission rate and enhanced the electrochemical signal, which led to an increase of the detection sensitivity. Based on the specific antibody-antigen interaction, a label-free immunosensor based on Pd nanoplates was developed for sensing of AFP. The current method allows us to detect AFP over a wide concentration range from 0.01 to 75.0ng/mL with a detection limit of 4pg/mL. The proposed immunosensor has been used to determine AFP in human serum with satisfactory results.
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Complete preservation of the mitral valve apparatus during mitral valve replacement for rheumatic mitral regurgitation in patients with an enlarged left ventricular chamber.
Heart Surg Forum
PUBLISHED: 06-28-2013
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The merits of retaining the subvalvular apparatus during mitral valve replacement (MVR) for chronic mitral regurgitation have been demonstrated in clinical investigations. This study was to investigate the feasibility of total preservation of the leaflet and subvalvular apparatus at the native anatomic position during MVR in a rheumatic population with enlarged left ventricular chamber.
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