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Find video protocols related to scientific articles indexed in Pubmed.
Solid-state dye-sensitized solar cells based on poly(3,4-ethylenedioxypyrrole) and metal-free organic dyes.
Chemphyschem
PUBLISHED: 11-15-2014
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Poly(3,4-ethylenedioxypyrrole) (PEDOP), combined with metal-free organic sensitizers, is efficiently used for the first time as the hole-transporting material in solid-state dye-sensitized solar cells. Devices employing PEDOP as the hole conductor and D35 or D21 L6 as the sensitizer show a ten-times-higher energy-conversion efficiency (of 4.5% and 3.3%, respectively) compared to Ru-Z907-based devices. This is due to the efficient suppression of electron recombination.
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Probiotics for preventing ventilator-associated pneumonia.
Cochrane Database Syst Rev
PUBLISHED: 10-26-2014
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Ventilator-associated pneumonia (VAP) is common in intensive care units (ICUs). Some evidence indicates that probiotics may reduce the incidence of VAP. Several additional published studies have demonstrated that probiotics are safe and efficacious in preventing VAP in ICUs. We aimed to systematically summarise the results of all available data to generate the best evidence for the prevention of VAP.
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240??W high-average-power square-shaped nanosecond all-fiber-integrated laser with near diffraction-limited beam quality.
Appl Opt
PUBLISHED: 10-17-2014
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We report an all-fiber-integrated high-average-power square-shaped nanosecond pulse laser operating at 1068 nm based on the master oscillator power amplifier configuration. The seed source is a passively mode-locked Yb-doped fiber laser with fundamental cavity repetition rate of 1.86 MHz. Output pulses with a square shape can be tuned in pulse width from 271 ps to the nanosecond level. The average output power reaches to 9.21 W after three preamplifiers. Finally, a main amplifier is developed to boost the average output power to 240 W, and the corresponding pulse energy and peak power are ?129.3???J and 36 kW, respectively. The efficiency of the main amplifier is ?61.3%, and the beam quality represented by M2 factors is below 1.3 and 1.2 in the X and Y directions.
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Four-wavelength laser based on intracavity BaWO4 Raman conversions of a dual-wavelength Q-switched Nd:YLF laser.
Opt Express
PUBLISHED: 10-17-2014
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By using diode-end-pumped acousto-optically Q-switched intracavity Raman laser configurations, we demonstrate a four-wavelength laser emitting at 1047.0, 1053.0, 1159.4 and 1166.8 nm. Two Nd:YLiF4 crystals are employed to generate 1047.0-nm and 1053.0-nm laser radiations. These two lasers are then frequency converted by a BaWO4 Raman crystal to generate 1159.4-nm and 1166.8-nm first-Stokes waves. With pulse synchronization realized, we obtain the maximum output powers of 427, 418, 423 and 332 mW for 1047.0-nm, 1053.0-nm, 1159.4-nm and 1166.8-nm lasers, respectively. The total optical-to-optical conversion efficiency is 15.1%.
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Total Syntheses of (-)-Huperzine Q and (+)-Lycopladines B and C.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 09-25-2014
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Utilizing a late-stage enamine bromofunctionalization strategy, the twelve-step total synthesis of (-)-huperzine Q was accomplished. Furthermore, the first total syntheses of (+)-lycopladines B and C are described. An unprecedented X-ray crystal structure of an unusual epoxyamine intermediate is also reported, and the synthetic application of this intermediate in natural product synthesis is demonstrated.
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Dexmedetomidine premedication attenuates concanavalin A-induced hepatitis in mice.
J Toxicol Sci
PUBLISHED: 09-23-2014
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Activated T cells selectively induced by concanavalin A (Con A) in liver are subsequent efficient resolution of inflammation. Activated T cells infiltrating in liver combined with pro-inflammatory cytokines are the major causes in Con A-induced liver injury. In our study, C57/BL mice were injected with Con A combined with dexmedetomidine or not. ALT and AST in blood and histopathology of liver were measured. T cell infiltration in liver was examined by flow cytometry and pro-inflammatory cytokines including IL-6, IL-10, TNF-?, and IFN-? in blood were measured by ELISA. The mRNA level of CXCL10 was detected by RT-PCR and the protein level of NF-?B was measured by Western-blot. We found that dexmedetomidine alleviated Con A-induced liver injury by down-regulating levels of ALT and AST in blood and the severity of histopathology, which reflect the severity of hepatitis induced by Con A. In addition, pro-inflammatory cytokines in blood were attenuated by dexmedetomidine. Dexmedetomidine restrained the phosphorylation of NF-?B I?B? and P-65 dramatically which may participate in the regulation of cytokines secretion. Moreover, CXCL10 mRNA attenuated by dexmedetomidine in liver may result in the lower level of CD4(+) T cells infiltration in liver. These results suggested that dexmedetomidine might be a potential compound in treating T cell-mediated liver injury.
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Anti-rheumatic agent auranofin induced apoptosis in chronic myeloid leukemia cells resistant to imatinib through both Bcr/Abl-dependent and -independent mechanisms.
Oncotarget
PUBLISHED: 09-07-2014
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Resistance to Imatinib mesylate (IM) is an emerging problem for patients with chronic myelogenous leukemia (CML). T315I mutation in the Bcr-Abl is the predominant mechanism of the acquired resistance to IM and second generation tyrosine kinase inhibitors (TKI). Therefore it is urgent to search for new measures to overcome TKI-resistance. Auranofin (AF), clinically used to treat rheumatic arthritis, was recently approved by US Food and Drug Administration for Phase II clinical trial to treat cancer. In contrast to the reports that AF induces apoptosis by increasing intracellular reactive oxygen species (ROS) levels via inhibiting thioredoxin reductase, our recent study revealed that AF-induced apoptosis depends on inhibition of proteasomal deubiquitinases (UCHL5 and USP14). Here we report that (i) AF induces apoptosis in both Bcr-Abl wild-type cells and Bcr-Abl-T315I mutation cells and inhibits the growth of IM-resistant Bcr-Abl-T315I xenografts in vivo; (ii) AF inhibits Bcr-Abl through both downregulation of Bcr-Abl gene expression and Bcr-Abl cleavage mediated by proteasome inhibition-induced caspase activation; (iii) proteasome inhibition but not ROS is required for AF-induced caspase activation and apoptosis. These findings support that AF overcomes IM resistance through both Bcr/Abl-dependent and -independent mechanisms, providing great clinical significance for cancer treatment.
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Prognostic significance of overexpressed p16INK4a in patients with cervical cancer: a meta-analysis.
PLoS ONE
PUBLISHED: 09-04-2014
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p16INK4a is a tumor suppressor protein which is induced in cells upon the interaction of high-risk HPV E7 with the retinoblastoma protein by a positive feedback loop, but cannot exert its suppressing effect. Previous reports suggested that p16INK4a immunostaining allows precise identification of even small CIN or cervical cancer lesions in biopsies. The prognostic value of overexpressed p16INK4a in cervical cancer has been evaluated for several years while the results remain controversial. We performed a systematic review and meta-analysis of studies assessing the clinical and prognostic significance of overexpression of p16INK4a in cervical cancer.
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Synthesis of One-Dimensional Copper Sulfide Nanorods as High-Performance Anode in Lithium Ion Batteries.
ChemSusChem
PUBLISHED: 08-19-2014
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Nanorod-like CuS and Cu2 S have been fabricated by a hydrothermal approach without using any surfactant and template. The electrochemical behavior of CuS and Cu2 S nanorod anodes for lithium-ion batteries reveal that they exhibit stable lithium-ion insertion/extraction reversibility and outstanding rate capability. Both of the electrodes exhibit excellent capacity retentions irrespective of the rate used, even at a high current density of 3200?mA?g(-1) . More than 370?mAh?g(-1) can be retained for the CuS electrode and 260?mAh?g(-1) for the Cu2 S electrode at the high current rate. After 100?cycles at 100?mA?g(-1) , the obtained CuS and Cu2 S electrodes show discharge capacities of 472 and 313?mAh?g(-1) with retentions of 92?% and 96?%, respectively. Together with the simplicity of fabrication and good electrochemical properties, CuS and Cu2 S nanorods are promising anode materials for practical use the next-generation lithium-ion batteries.
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Carbazole-based hole-transport materials for efficient solid-state dye-sensitized solar cells and perovskite solar cells.
Adv. Mater. Weinheim
PUBLISHED: 08-15-2014
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Two carbazole-based small molecule hole-transport materials (HTMs) are synthesized and investigated in solid-state dye-sensitized solar cells (ssDSCs) and perovskite solar cells (PSCs). The HTM X51-based devices exhibit high power conversion efficiencies (PCEs) of 6.0% and 9.8% in ssDSCs and PSCs, respectively. These results are superior or comparable to those of 5.5% and 10.2%, respectively, obtained for the analogous cells using the state-of-the-art HTM Spiro-OMeTAD.
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Hydroclimate variations in central and monsoonal Asia over the past 700 years.
PLoS ONE
PUBLISHED: 08-13-2014
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Hydroclimate variations since 1300 in central and monsoonal Asia and their interplay on interannual and interdecadal timescales are investigated using the tree-ring based Palmer Drought Severity Index (PDSI) reconstructions. Both the interannual and interdecadal variations in both regions are closely to the Pacific Decadal Oscillation (PDO). On interannual timescale, the most robust correlations are observed between PDO and hydroclimate in central Asia. Interannual hydroclimate variations in central Asia are more significant during the warm periods with high solar irradiance, which is likely due to the enhanced variability of the eastern tropical Pacific Ocean, the high-frequency component of PDO, during the warm periods. We observe that the periods with significant interdecadal hydroclimate changes in central Asia often correspond to periods without significant interdecadal variability in monsoonal Asia, particularly before the 19th century. The PDO-hydroclimate relationships appear to be bridged by the atmospheric circulation between central North Pacific Ocean and Tibetan Plateau, a key area of PDO. While, in some periods the atmospheric circulation between central North Pacific Ocean and monsoonal Asia may lead to significant interdecadal hydroclimate variations in monsoonal Asia.
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Photosynthetic responses and accumulation of mesotrione in two freshwater algae.
Environ Sci Process Impacts
PUBLISHED: 07-26-2014
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Mesotrione is a herbicide used for killing annual grasses and broad-leaved weeds in maize. A recent investigation has shown that mesotrione has been detected as an organic contaminant in aquatic environments and may have a negative impact on aquatic organisms. To evaluate the eco-toxicity of mesotrione to algae, experiments focusing on photosynthetic responses and mesotrione accumulation in Microcystis sp. and Scenedesmus quadricauda were carried out. Both algae treated with mesotrione at 0.05-10 mg L(-1) for 7 days reduced the photosynthetic capacity. The fluorescence of chlorophyll a, the maximal PSII activity (Fv/Fm), and the parameters (Ik, ? and ETRmax) of rapid light curves (RLCs) in both algae were decreased under mesotrione exposure. The 96 h EC50 values for mesotrione on S. quadricauda and Microcystis sp. were 4.41 and 6.19 mg L(-1), respectively. The latter shows more tolerance to mesotrione. Mesotrione was shown to be readily accumulated by both species. Such uptake of mesotrione led to the rapid removal of mesotrione from the medium. Overall, this study represents the initial comprehensive analyses of Microcystis sp. and S. quadricauda in adaptation to the mesotrione contaminated aquatic ecosystems.
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Novel hybrid management for aortic dissection with crevasse in the vicinity of critical branching: report of 53 cases.
Acta Cardiol
PUBLISHED: 07-18-2014
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Open surgery for aortic dissection with crevasse in the vicinity of critical branching (CVCB-AD) is frequently associated with several complications and a high mortality rate. We report the management of 53 patients with CVCB-AD who underwent a novel hybrid procedure including both open surgery and endovascular stenting. During the follow-up period no paraplegia, stroke, renal failure, or bleeding was observed, and no elective or emergency surgical conversion was required, suggesting that this hybrid procedure is a feasible, safe, and effective strategy for the treatment of CVCB-AD.
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Clinically used antirheumatic agent auranofin is a proteasomal deubiquitinase inhibitor and inhibits tumor growth.
Oncotarget
PUBLISHED: 07-01-2014
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Proteasomes are attractive emerging targets for anti-cancer therapies. Auranofin (Aur), a gold-containing compound clinically used to treat rheumatic arthritis, was recently approved by US Food and Drug Administration for Phase II clinical trial to treat cancer but its anti-cancer mechanism is poorly understood. Here we report that (i) Aur shows proteasome-inhibitory effect that is comparable to that of bortezomib/Velcade (Vel); (ii) different from bortezomib, Aur inhibits proteasome-associated deubiquitinases (DUBs) UCHL5 and USP14 rather than the 20S proteasome; (iii) inhibition of the proteasome-associated DUBs is required for Aur-induced cytotoxicity; and (iv) Aur selectively inhibits tumor growth in vivo and induces cytotoxicity in cancer cells from acute myeloid leukemia patients. This study provides important novel insight into understanding the proteasome-inhibiting property of metal-containing compounds. Although several DUB inhibitors were reported, this study uncovers the first drug already used in clinic that can inhibit proteasome-associated DUBs with promising anti-tumor effects.
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Effects of TSP-1-696 C/T polymorphism on bladder cancer susceptibility and clinicopathologic features.
Cancer Genet
PUBLISHED: 06-26-2014
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Thrombospondin-1 (TSP-1) is a glycoprotein that plays a major role in bladder cancer. We investigated the relationship between the distribution of the TSP-1 -696 C/T polymorphism (rs2664139) and the clinical features of bladder cancer. TaqMan assay was used to determine the genotype among the 609 cases and 670 controls in a Chinese population. Logistic regression was used to assess the association between the polymorphism and bladder cancer risk. Compared with the CT/TT genotypes, the CC genotype was associated with a significantly increased risk of bladder cancer (adjusted odds ratio [OR] 1.43, 95% CI 1.01-2.04), which was more prominent among the male participants (OR 1.82, 95% CI 1.20-2.76). The polymorphism was associated with a higher risk of developing grade 3 (OR 1.84, 95% CI 1.00-3.36), multiple-tumor (OR 1.81, 95% CI 1.08-3.02), and large-tumor (OR 1.94, 95% CI 1.22-3.10) bladder cancers. These observations suggest that the TSP-1 -696 C/T polymorphism may contribute to bladder cancer susceptibility in the Chinese population.
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Effect of protective ventilation on postoperative pulmonary complications in patients undergoing general anaesthesia: a meta-analysis of randomised controlled trials.
BMJ Open
PUBLISHED: 06-26-2014
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To determine whether anaesthetised patients undergoing surgery could benefit from intraoperative protective ventilation strategies.
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Overexpression of peroxiredoxin 2 inhibits TGF-?1-induced epithelial-mesenchymal transition and cell migration in colorectal cancer.
Mol Med Rep
PUBLISHED: 05-28-2014
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Although human peroxiredoxin 2 (PRDX2) has been implicated in tumor progression (e.g., invasion and metastasis), little is known regarding its role in the epithelial?mesenchymal transition (EMT) process during tumorigenesis. The present study offers the first evidence, to the best of our knowledge, that the antioxidant enzyme PRDX2 has an important role in regulating the EMT process. It was demonstrated that overexpression of PRDX2 leads to changes in cell morphology in vitro and potent inhibition of the transforming growth factor (TGF)??1?induced EMT and cell migration of colorectal cancer (CRC) cells. Furthermore, PRDX2 regulates the expression of EMT markers, EMT?related transcription factors and metastasis?related factors in CRC cells. These results provide new insight into the role of PRDX2 in regulating EMT, cell migration and metastasis of CRC cells. It was concluded that the upregulation of PRDX2 may be correlated with EMT and contributes to the pathogenesis of CRC by inhibiting EMT, cell migration and metastasis. Taken together, these ?ndings suggest that PRDX2 may be a key regulator of invasion and metastasis by inhibiting EMT of CRC cells, and also identifies a therapeutic strategy to effectively decrease the lethality of highly malignant types of CRC.
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[Systematic review of primary stenting for arteriosclerotic occlusion in below-the-knee arteries].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 05-24-2014
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To evaluate the clinical value of primary stenting for treating peripheral arterial diseases in below-the-knee arteries by comparing to percutaneous transluminal angioplasty (PTA).
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A novel proteasome inhibitor suppresses tumor growth via targeting both 19S proteasome deubiquitinases and 20S proteolytic peptidases.
Sci Rep
PUBLISHED: 05-21-2014
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The successful development of bortezomib-based therapy for treatment of multiple myeloma has established proteasome inhibition as an effective therapeutic strategy, and both 20S proteasome peptidases and 19S deubiquitinases (DUBs) are becoming attractive targets of cancer therapy. It has been reported that metal complexes, such as copper complexes, inhibit tumor proteasome. However, the involved mechanism of action has not been fully characterized. Here we report that (i) copper pyrithione (CuPT), an alternative to tributyltin for antifouling paint biocides, inhibits the ubiquitin-proteasome system (UPS) via targeting both 19S proteasome-specific DUBs and 20S proteolytic peptidases with a mechanism distinct from that of the FDA-approved proteasome inhibitor bortezomib; (ii) CuPT potently inhibits proteasome-specific UCHL5 and USP14 activities; (iii) CuPT inhibits tumor growth in vivo and induces cytotoxicity in vitro and ex vivo. This study uncovers a novel class of dual inhibitors of DUBs and proteasome and suggests a potential clinical strategy for cancer therapy.
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Identification of putative virulence-associated genes among Haemophilus parasuis strains and the virulence difference of different serovars.
Microb. Pathog.
PUBLISHED: 05-04-2014
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This study was aimed at determining virulence-associated genes among Haemophilus parasuis (H. parasuis) strains, and supplying for the Kielstein-Rapp-Gabrielson serotyping scheme. The subtractive fragments, obtained through suppression subtractive hybridization and reverse Southern blot hybridization, were found to encode genes representative of 7 different functions. PCR was used to investigate the distribution of these fragments in H. parasuis strains isolated from different infection sites in pigs. Mice challenge was then used to analyze the correlationship between subtractive fragments, infection sites and bacterial virulence. Eight weeks old female BALB/c mice (10 mice/group) were inoculated intraperitoneally with 3.0 × 10(9) CFU suspension (0.5 ml/mouse) of H. parasuis strains in PBS. Results indicated that H. parasuis possessed varied virulence even among the same serovar strains. Transcription units hsdR, hsdS, gpT and ompP2, identified from the subtractive fragments, were uniformly expressed in highly virulent strains, while absent in weakly virulent strains, and demonstrated variable degrees of expression in moderately virulent strains. Moreover, H. parasuis strains, isolated from pericardium and heart blood, were all highly virulent strains, while from nasal cavity and joint were moderately or weakly virulent strains. This study indicated that fragments hsdR, hsdS, gpT and ompP2 were associated with the virulence of H. parasuis. The virulence of H. parasuis strains isolated from different infection sites was different. The current research provides a new reference for determining bacterial virulence in different H. parasuis strains.
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Comparison of fiber lasers based on distributed side-coupled cladding-pumped fibers and double-cladding fibers.
Appl Opt
PUBLISHED: 05-03-2014
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We compare both analytically and numerically the distributed side-coupled cladding-pumped (DSCCP) fiber lasers and double cladding fiber (DCF) lasers. We show that, through optimization of the coupling and absorbing coefficients, the optical-to-optical efficiency of DSCCP fiber lasers can be made as high as that of DCF lasers. At the same time, DSCCP fiber lasers are better than the DCF lasers in terms of thermal management.
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Diversity-oriented synthesis of Lycopodium alkaloids inspired by the hidden functional group pairing pattern.
Nat Commun
PUBLISHED: 04-15-2014
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Natural products continue to provide a rich source of inspiration for both chemists and biologists. The efficient synthesis of bioactive natural products or natural product-like molecules has offered tremendous opportunities for complex biological processes exploration and drug discovery. However, because natural products usually contain numerous stereogenic centres and polycyclic ring systems, significant synthetic challenges remain. Here we employ the build/couple/pair strategy that is frequently used in diversity-oriented synthesis to obtain skeletally diverse compounds with complexities comparable to natural products. Inspired by the functional group pairing patterns hidden in Lycopodium alkaloids, we efficiently and in parallel construct four natural products, (+)-Serratezomine A, (-)-Serratinine, (+)-8?-Hydroxyfawcettimine and (-)-Lycoposerramine-U, as well as six different unnatural scaffolds, following the advanced build/couple/pair algorithm. This newly developed strategy is expected to be applied to the efficient synthesis of other complex natural products possessing functional group pairing patterns as well as skeletally diverse natural product-like molecules.
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[Protective effect of necrostatin-1 on the liver of rats with trauma induced hemorrhagic shock].
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue
PUBLISHED: 03-22-2014
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To investigate the effects of necrostatin-1( Nec-1) on the liver of rats with trauma induced hemorrhagic shock.
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Enhanced proliferation and defective activation-induced cell death of CD4+ T cells in childhood asthma.
Asian Pac. J. Allergy Immunol.
PUBLISHED: 03-20-2014
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Hyperactivation of CD4+ T cells in peripheral blood and airway tissues has been suggested to play a key role in the development and maintenance of chronic inflammation in childhood asthma. However, the underlying mechanisms are not yet clear.
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Inter-laboratory validation of the in-vivo flow cytometric micronucleus analysis method (MicroFlow(®)) in China.
Mutat Res Genet Toxicol Environ Mutagen
PUBLISHED: 03-19-2014
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Although inter-laboratory validation efforts of the in-vivo micronucleus (MN) assay based on flow cytometry (FCM) have taken place in the EU and US, none have been organized in China. Therefore, an inter-laboratory study that included eight laboratories in China and one experienced reference laboratory in the US was coordinated to validate the in-vivo FCM MicroFlow(®) method to determine the frequency of micro-nucleated reticulocytes (MN-RETs) in rat blood. Assay reliability and reproducibility were evaluated with four known genotoxicants, and the results obtained with the FCM method were compared with the outcome of the traditional evaluation of bone-marrow micronuclei by use of microscopy. Each of the four chemicals was tested at three sites (two in China and the one US reference laboratory). After three consecutive daily exposures to a genotoxicant, blood and bone-marrow samples were obtained from rats 24h after the third dose. MN-RET frequencies were measured in 20,000 RET in blood by FCM, and micro-nucleated polychromatic erythrocyte (MN-PCE) frequencies were measured in 2,000 PCEs in bone marrow by microscopy. For both methods, each genotoxicant was shown to induce a statistically significant increase in the frequency of MN after treatment with at least one dose. Where more doses than one caused an increase, responses occurred in a dose-dependent manner. Spearman's correlation coefficient (rs) for FCM-based MN-RET vs microscopy-based MN-PCE measurements (eight experiments, 200 paired measurements) was 0.723, indicating a high degree of correspondence between methods and compartments. The rs value for replicate FCM MN-RET measurements performed at the eight collaborative laboratories was 0.940 (n=200), and between the eight FCM laboratories with the reference laboratory was 0.933 (n=200), suggesting that the automated method is very well transferable between laboratories. The FCM micronucleus analysis method is currently used in many countries worldwide, and these data support its use for evaluating the in-vivo genotoxic potential of test chemicals in China.
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Giant vegetation in the right ventricle caused by Staphylococcus aureus and Candida mycoderma.
Heart Surg Forum
PUBLISHED: 03-18-2014
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Infective endocarditis (IE) is considered a multifactorial disease. Providing an early diagnosis and invasive treatment together with effective antibiotic treatment remain critical tasks for the cardiologist and the surgeon. Right ventricular endocarditis is a rare type of endocarditis usually caused by Staphylococcus aureus and Candida mycoderma.
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Genetic variations in IL1A and IL1RN are associated with the risk of preeclampsia in Chinese Han population.
Sci Rep
PUBLISHED: 03-14-2014
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Preeclampsia (PE) is an excessive systemic inflammation response with dysfunction of endothelial. Our study was to investigate the association between genetic variations in IL-1 and the susceptibility to PE in Chinese Han population. 402 PE patients and 554 normal pregnant women of third trimester were enrolled. The polymorphisms of rs315952 in IL1RN and rs17561 in IL1A were genotyped by TaqMan allelic discrimination real-time PCR. Obviously statistic difference of the genotypic frequencies were found in both of IL1RN rs315952 and IL1A rs17561 between cases and controls (for rs315952, P = 0.001; for rs17561, P = 0.021.). For rs315952, the C allele was associated with development of PE (P = 0.003, OR = 1.319, 95%CI 1.099-1.583). Patients with CC or CT genotype were less likely to develop severe PE than patients carrying TT genotype(P < 0.001, OR = 0.24, 95%CI 0.15-0.40). For rs17561, the C allele was the risk factor for predisposition to PE (P = 0.012, OR = 1.496, 95%CI 1.089-2.055). Our results suggest IL1RN and IL1A may involve in the development of PE in Chinese Han population.
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Suxiaojiuxin pill enhances atherosclerotic plaque stability by modulating the MMPs/TIMPs balance in ApoE-deficient mice.
J. Cardiovasc. Pharmacol.
PUBLISHED: 03-14-2014
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: Suxiaojiuxin pill (SX) is a famous Chinese formulated product, which has been used to treat coronary heart disease and angina pectoris in China. This study was carried out to investigate the effect and possible mechanism of SX on the stability of atherosclerotic plaque in ApoE-deficient mice. ApoE-/- mice of 6-8 weeks old were fed with high-fat diet for developing artherosclerosis. After oral administration of SX for 8 weeks, histopathology of aortic plaque was performed by Sudan III and hematoxylin-eosin staining, and muscle protein was detected by Western blotting (WB). The mRNA and proteins associated with aortic plaque stability were detected by reverse transcription-polymerase chain reaction and WB, respectively. SX treatment could not only reduce serum triglyceride level and plaque area but also increase fibrous cap thickness and collagen content compared with the model group. WB results showed that SX could increase ?-smooth muscle actin, tissue inhibitor of metalloproteinase 1 (TIMP-1), and TIMP-2 protein expression, whereas decrease matrix metalloproteinase 2 (MMP-2) and MMP-9 protein expression. Moreover, SX could upregulate the expression of ?-smooth muscle actin mRNA and downregulate the expression of vascular endothelial growth factor mRNA. These results showed that SX could enhance atherosclerotic plaque stability in ApoE-deficient mice. The mechanism may be associated with modulating the MMPs/TIMPs balance.
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Salidroside attenuates concanavalin A-induced hepatitis via modulating cytokines secretion and lymphocyte migration in mice.
Mediators Inflamm.
PUBLISHED: 03-05-2014
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Salidroside, isolated from the medicinal plant Rhodiola, was reported to serve as an "adaptogen." This study was designed to explore the protective effect of salidroside on concanavalin A- (Con A-) induced hepatitis in mice and investigate potential mechanisms. C57BL/6 mice were randomly divided into control group, Con A group, and salidroside group. Salidroside (50?mg/kg) was injected intravenously followed by Con A administration. The levels of ALT, AST, inflammatory cytokines and CXCL-10 were examined. The pathological damage of livers was assessed, the amounts of phosphorylated I?B? and p65 were measured, and the numbers of CD4(+) and CD8(+) T lymphocytes in the blood, spleen and infiltrated in the liver were calculated. Our results showed that salidroside pretreatment reduced the levels of ALT, AST dramatically and suppressed the secretion of proinflammatory cytokines through downregulating the activity of NF-?B partly. Salidroside altered the distribution of CD4(+) and CD8(+) T lymphocyte in the liver and spleen through regulating CXCL-10 and decreased the severity of liver injuries. In conclusion, these results confirm the efficacy of salidroside in the prevention of immune mediated hepatitis in mice.
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Anacardic acid induces cell apoptosis associated with induction of ATF4-dependent endoplasmic reticulum stress.
Toxicol. Lett.
PUBLISHED: 02-24-2014
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Anacardic acid (6-pentadecylsalicylic acid, AA), a natural compound isolated from the traditional medicine Amphipterygium adstringens, has been reported to possess antitumor activities. However, its molecular targets have not been thoroughly studied. Here, we report that AA is a potent inducer of endoplasmic reticulum (ER) stress, leading to apoptosis in hepatoma HepG2 and myeloma U266 cells. Induction of ER stress by AA was supported by a dose- and time-dependent increase in expression of the ER signaling downstream molecules, such as GRP78/BiP, phosphorylated eIF2?, ATF4 and CHOP in both HepG2 and U266 cell lines. Blockage of ATF4 expression by siRNA partially inhibited, while knockdown of CHOP expression by siRNA slightly increased AA-induced cell death in these cells. In addition, AA suppressed HepG2 xenograft tumor growth, associated with increased ER stress in vivo. These results suggest that AA induces tumor cell apoptosis associated with ATF4-dependent ER stress.
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Association between NFKB1 -94ins/del ATTG Promoter Polymorphism and Cancer Susceptibility: An Updated Meta-Analysis.
Int J Genomics
PUBLISHED: 02-21-2014
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Nuclear factor- ? B is associated with the pathogenesis of numerous malignancies, and the functional polymorphism -94ins/del ATTG (rs28362491) in the human NFKB1 gene is associated with cancer risk. Previous studies on the association between the -94ins/del ATTG polymorphism and cancer risk reported conflicting results. To clarify this relationship, we performed a meta-analysis of 21 case-control studies involving 6127 cases and 9238 controls. We used pooled odds ratios (ORs) with their 95% confidence intervals (95% CIs) to assess the association. We found that the NFKB1 promoter -94ins/del ATTG polymorphism was significantly associated with cancer risk in four genetic models (ins/ins versus del/del, OR = 1.47, 95% CI = 1.11-1.93; dominant model, OR = 1.26, 95% CI = 1.03-1.53; recessive model, OR = 1.26, 95% CI = 1.05-1.51; ins allele versus del allele, OR = 1.19, 95% CI = 1.05-1.35). Stratified analyses revealed a significant association between the polymorphism and ovarian, oral, and prostate cancers. Similar results were determined in an Asian population and not in a Caucasian population. Thus, our results suggested that the polymorphism can contribute to cancer risk. Moreover, the polymorphism can exert race- and cancer-specific effects on cancer risk. Further large-scale and functional studies are necessary to elucidate this possible effect.
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3Cpro of foot-and-mouth disease virus antagonizes the interferon signaling pathway by blocking STAT1/STAT2 nuclear translocation.
J. Virol.
PUBLISHED: 02-19-2014
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Foot-and-mouth disease virus (FMDV) causes a highly contagious, debilitating disease in cloven-hoofed animals with devastating economic consequences. To survive in the host, FMDV has evolved to antagonize the host type I interferon (IFN) response. Previous studies have reported that the leader proteinase (L(pro)) and 3C(pro) of FMDV are involved in the inhibition of type I IFN production. However, whether the proteins of FMDV can inhibit type I IFN signaling is less well understood. In this study, we first found that 3C(pro) of FMDV functioned to interfere with the JAK-STAT signaling pathway. Expression of 3C(pro) significantly reduced the transcript levels of IFN-stimulated genes (ISGs) and IFN-stimulated response element (ISRE) promoter activity. The protein level, tyrosine phosphorylation of STAT1 and STAT2, and their heterodimerization were not affected. However, the nuclear translocation of STAT1/STAT2 was blocked by the 3C(pro) protein. Further mechanistic studies demonstrated that 3C(pro) induced proteasome- and caspase-independent protein degradation of karyopherin ?1 (KPNA1), the nuclear localization signal receptor for tyrosine-phosphorylated STAT1, but not karyopherin ?2, ?3, or ?4. Finally, we showed that the protease activity of 3C(pro) contributed to the degradation of KPNA1 and thus blocked STAT1/STAT2 nuclear translocation. Taken together, results of our experiments describe for the first time a novel mechanism by which FMDV evolves to inhibit IFN signaling and counteract host innate antiviral responses.
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Species coexistence in a lattice-structured habitat: effects of species dispersal and interactions.
J. Theor. Biol.
PUBLISHED: 02-13-2014
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Opinions differ on how the spatial distribution of species over space affects species coexistence. Here, we constructed both mean-field and pair approximation (PA) models to explore the effects of interspecific and intraspecific interactions and dispersal modes on species coexistence. We found that spatial structure resulting from species dispersal traits and neighboring interactions in PA model did not promote coexistence if two species had the same traits, though it might intensify the contact frequency of intraspecific competition. If two species adopt different dispersal modes, the spatial structure in PA would make the coexistence or founder control less likely since it alters the species effective birth rate. This suggests that the spatial distribution caused by neighboring interactions and local dispersal does not affect species coexistence unless it adequately alters the effective birth rate for two species. Besides, we modeled how the initial densities and patterns affected population dynamics and revealed how the final spatial pattern was generated.
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Novel two-stage surgical treatment for Cantrell syndrome complicated by severe pulmonary hypertension: a case report.
J Med Case Rep
PUBLISHED: 01-27-2014
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Cantrell syndrome is a rare syndrome of congenital defects, which can be complicated by severe pulmonary hypertension and left ventricular diverticulum; it has proved difficult to treat in clinical practice.
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Poly(l-lactide-co-2-(2-methoxyethoxy)ethyl methacrylate): a biodegradable polymer with protein resistance.
Colloids Surf B Biointerfaces
PUBLISHED: 01-25-2014
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We have synthesized poly(l-lactide-co-2-(2-methoxyethoxy)ethyl methacrylate) (LA-co-MEO2MA) containing both degradable and protein resistant units via hybrid copolymerization with (1-tert-butyl-4,4,4-tris(dimethylamino)-2,2-bis[tris(dimethylamino)phophoranylidenamino]-2?5,?5-catenadi(phosphazene) (t-BuP4) as the catalyst. Nuclear magnetic resonance (NMR) and differential scanning calorimetry (DSC) show that LA-co-MEO2MA is a random copolymer. The studies of quartz crystal microbalance with dissipation (QCM-D) demonstrate that the copolymer enzymaticlly degrades much faster than poly(l-lactide) (PLA) homopolymer due to its lower crystallinity. We have also investigated the adsorption of bovine serum albumin (BSA), lysozyme or fibrinogen on a LA-co-MEO2MA surface in real time by use of QCM-D and surface plasmon resonance (SPR). Our studies reveal that the polymer is protein resistant depending on MEO2MA content. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay experiments demonstrate that the polymer has a low cytotoxicity.
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Proteomic analysis of differential protein expression in platelets of septic patients.
Mol. Biol. Rep.
PUBLISHED: 01-16-2014
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Sepsis is one of the major health problems all over the world. Early diagnostic of sepsis is an attractive strategy to decrease the mortality of septic patients. However, an effective biomarker that fulfills all the necessary requirements for the accurate characterization of sepsis is still unavailable until now. In this study, the 2-DE technique followed by mass spectrometry and a database search was used for searching and identifying the differential expressed proteins in platelets between septic patients and paired healthy controls. Platelet 2-DE profiles of septic patients and paired healthy controls with high resolution and reproducibility were obtained. Differential platelet 2-DE profiles between septic patients and paired healthy controls were established. Differential protein spots between normal healthy volunteers and septic patients from platelet 2-DE profiles were identified by 2-DE followed with mass spectrometry and a database search. Five proteins with increased expression were identified between septic patients and healthy controls from platelet samples. These up-expressed proteins were EF-hand calcium-binding domain-containing protein 7, actin, interleukin-1?, glycoprotein IX, and glycoprotein IIB. Sepsis induces a complex regulation of platelet protein changes. Our study highlights the important role of these differential expressed proteins in sepsis, which deserve further research as potential candidates for therapeutic strategies. Furthermore, our research is beneficial for the future developments of sepsis diagnosis and therapy.
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Ginsenoside Rg1 protects mouse liver against ischemia-reperfusion injury through anti-inflammatory and anti-apoptosis properties.
J. Surg. Res.
PUBLISHED: 01-09-2014
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Ginsenoside Rg1, the major effective component of ginseng, possesses a variety of pharmacologic activities. The objective of this study was to investigate the effects of Rg1 on liver ischemia-reperfusion (IR) injury and explore its potential mechanisms.
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Bioinformatic identification and experimental validation of miRNAs from foxtail millet (Setaria italica).
Gene
PUBLISHED: 01-07-2014
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MiRNAs are a novel group of non-coding small RNAs that negatively regulate gene expression. Many miRNAs have been identified and investigated extensively in plant species with sequenced genomes. However, few miRNAs have been identified in foxtail millet (Setaria italica), which is an ancient cereal crop of great importance for dry land agriculture. In this study, 271 foxtail millet miRNAs belonging to 44 families were identified using a bioinformatics approach. Twenty-three pairs of sense/antisense miRNAs belonging to 13 families, and 18 miRNA clusters containing members of 8 families were discovered in foxtail millet. We identified 432 potential targets for 38 miRNA families, most of which were predicted to be involved in plant development, signal transduction, metabolic pathways, disease resistance, and environmental stress responses. Gene ontology (GO) analysis revealed that 101, 56, and 23 target genes were involved in molecular functions, biological processes, and cellular components, respectively. We investigated the expression patterns of 43 selected miRNAs using qRT-PCR analysis. All of the miRNAs were expressed ubiquitously with many exhibiting different expression levels in different tissues. We validated five predicted targets of four miRNAs using the RNA ligase mediated rapid amplification of cDNA end (5'-RLM-RACE) method.
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The control of tendon-driven dexterous hands with joint simulation.
Sensors (Basel)
PUBLISHED: 01-03-2014
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An adaptive impedance control algorithm for tendon-driven dexterous hands is presented. The main idea of this algorithm is to compensate the output of the classical impedance control by an offset that is a proportion-integration-differentiation (PID) expression of force error. The adaptive impedance control can adjust the impedance parameters indirectly when the environment position and stiffness are uncertain. In addition, the position controller and inverse kinematics solver are specially designed for the tendon-driven hand. The performance of the proposed control algorithm is validated by using MATLAB and ADAMS software for joint simulation. ADAMS is a great software for virtual prototype analysis. A tendon-driven hand model is built and a control module is generated in ADAMS. Then the control system is built in MATLAB using the control module. The joint simulation results demonstrate fast response and robustness of the algorithm when the environment is not exactly known, so the algorithm is suitable for the control of tendon-driven dexterous hands.
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Polyethylene glycol-modified dendrimer-entrapped gold nanoparticles enhance CT imaging of blood pool in atherosclerotic mice.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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We report a new use of dendrimer-entrapped gold nanoparticles (Au DENPs) modified by polyethylene glycol (PEG) with good biocompatibility for in vitro and in vivo imaging of atherosclerotic mice by computed tomography (CT). In this study, Au DENPs were synthesized using poly(amidoamine) (PAMAM) dendrimers of generation 5 (G5.NH2) modified by PEG monomethyl ether (G5.NH2-mPEG20) as templates. In vitro cytotoxicity and flow cytometry assays show that the formed PEGylated Au DENPs have good biocompatibility and are non-cytotoxic at the Au concentration up to 300 ?M. Silver staining and transmission electron microscopy (TEM) further confirm that the Au DENPs are able to be uptaken by macrophages and are located dominantly in the lysosomes of the cells. Importantly, the formed PEGylated Au DENPs are able to be used for CT imaging of murine macrophages in vitro and macrophages in atherosclerotic mice in vivo using apolipoprotein-E-gene-deficient mice as a model. These findings suggest that the formed PEGylated Au DENPs are a promising contrast agent for CT imaging of atherosclerosis.
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Reversal of muscle atrophy by Zhimu-Huangbai herb-pair via Akt/mTOR/FoxO3 signal pathway in streptozotocin-induced diabetic mice.
PLoS ONE
PUBLISHED: 01-01-2014
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Skeletal muscle atrophy is one of the serious complications of diabetes. Zhimu-Huangbai herb-pair (ZB) is widely used in Chinese traditional medicine formulas for treating Xiaoke (known as diabetes) and its complications. However, the effect of ZB on reversal of muscle atrophy and the underlying mechanisms remain unknown. In this research, we investigated the effect and possible mechanisms of ZB on skeletal muscle atrophy in diabetic mice. Animal model of diabetic muscle atrophy was developed by high fat diet (HFD) feeding plus streptozotocin (STZ) injection. After oral adminstration of ZB for 6 weeks, the effects of ZB on reversal of muscle atrophy and the underlying mechanisms were evaluated by biochemical, histological and western blot methods. The skeletal muscle weight, strength, and cross-sectional area of diabetic mice were significantly increased by ZB treatment. Biochemical results showed that ZB treatment reduced the serum glucose level, and elevated the serum insulin-like growth factor 1 (IGF-1) and insulin levels significantly compared with untreated diabetic group. The western blot results showed that ZB activated the mTOR signal pathway, shown as increased phosphorylations (p-) of Akt, mTOR, Raptor, S6K1 and reduced Foxo3 expression compared with the model group. ZB could reverse muscle atrophy in diabetic mice. This may be through activation of mTOR signaling pathway that promotes protein synthesis, and inactivation foxo3 protein that inhibits protein degradation. These findings suggested that ZB may be considered as a potential candidate drug in treatment of diabetic muscle atrophy.
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Autophagic-lysosomal inhibition compromises ubiquitin-proteasome system performance in a p62 dependent manner in cardiomyocytes.
PLoS ONE
PUBLISHED: 01-01-2014
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Intracellular protein degradation is primarily performed by the ubiquitin-proteasome system (UPS) and the autophagic-lysosomal pathway (ALP). The interplay between these two pathways has been rarely examined in intact animals and the mechanism underlying the interplay remains unclear. Hence, we sought to test in vivo and in vitro the impact of inhibition of the ALP on UPS proteolytic performance in cardiomyocytes and to explore the underlying mechanism. Transgenic mice ubiquitously expressing a surrogate UPS substrate (GFPdgn) were treated with bafilomycin-A1 (BFA) to inhibit the ALP. Myocardial and renal GFPdgn protein levels but not mRNA levels were increased at 24 hours but not 3 hours after the first injection of BFA. Myocardial protein abundance of key proteasome subunits and the activities of proteasomal peptidases were not discernibly altered by the treatment. In cultured neonatal rat ventricular myocytes (NRVMs), the surrogate UPS substrate GFPu and a control red fluorescence protein (RFP) were co-expressed to probe UPS performance. At 12 hours or 24 hours after ALP inhibition by 3-methyladenine (3-MA) or BFA, GFPu/RFP protein ratios and the protein half-life of GFPu were significantly increased, which is accompanied by increases in p62 proteins. Similar findings were obtained when ALP was inhibited genetically via silencing Atg7 or Rab7. ALP inhibition-induced increases in GFPu and p62 are co-localized in NRVMs. siRNA-mediated p62 knockdown prevented ALP inhibition from inducing GFPu accumulation in NRVMs. We conclude that in a p62-dependent fashion, ALP inhibition impairs cardiac UPS proteolytic performance in cardiomyocytes in vitro and in vivo.
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Highly efficient expression of interleukin-2 under the control of rabbit ?-globin intron II gene enhances protective immune responses of porcine reproductive and respiratory syndrome (PRRS) DNA vaccine in pigs.
PLoS ONE
PUBLISHED: 01-01-2014
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Highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) had caused catastrophic losses in swine industry in China. The current inactivated vaccine provided only limited protection, and the attenuated live vaccine could protect piglets against the HP-PRRSV but there was a possibility that the attenuated virus returned to high virulence. In this study, the eukaryotic expression vector pVAX1© was modified under the control of rabbit ?-globin intron II gene and the modified vector pMVAX1© was constructed. Porcine interleukin-2 (IL-2) and GP3-GP5 fusion protein of HP-PRRSV strain SD-JN were highly expressed by pMVAX1©. Mice inoculated with pMVAX1©-GP35 developed significantly higher PRRSV-specific antibody responses and T cell proliferation than those vaccinated with pVAX1©-GP35. pMVAX1©-GP35 was selected as PRRS DNA vaccine candidate and co-administrated with pVAX1©-IL-2 or pMVAX1©-IL-2 in pigs. pMVAX1©-IL-2+pMVAX1©-GP35 could provide enhanced PRRSV-specific antibody responses, T cell proliferation, Th1-type and Th2-type cytokine responses and CTL responses than pMVAX1©-GP35 and pVAX1©-IL-2+pMVAX1©-GP35. Following homologous challenge with HP-PRRSV strain SD-JN, similar with attenuated PRRS vaccine group, pigs inoculated with pMVAX1©-IL-2+pMVAX1©-GP35 showed no clinical signs, almost no lung lesions and no viremia, as compared to those in pMVAX1©-GP35 and pVAX1©-IL-2+pMVAX1©-GP35 groups. It indicated that pMVAX1©-IL-2 effectively increases humoral and cell mediated immune responses of pMVAX1©-GP35. Co-administration of pMVAX1©-IL-2 and pMVAX1©-GP35 might be attractive candidate vaccines for preventing HP-PRRSV infections.
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Positive Inductive Effect of Swine Interleukin-4 on Immune Responses Elicited by Modified Live Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) Vaccine.
Viral Immunol.
PUBLISHED: 12-17-2013
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Abstract Porcine reproductive and respiratory syndrome (PRRS) has become one of the most economically important diseases to the global pork industry. Currently, the efficacies of available commercial vaccines remain questionable: the modified live-PRRSV vaccines (MLVs) were generally effective but variable in sufficient protection, and the outcomes of inactivated-PRRSV vaccines (IVs) in the field were not very promising. In the present study, we investigated the effect of swine interleukin 4 (IL-4) on the development of virus-specific immune responses elicited by an MLV. The antibody titer against PRRSV membrane proteins in pigs elicited by MLV plus recombinant plasmid encoding IL-4 (group 3) was significantly higher than those elicited by MLV alone (group 1) and MLV plus empty plasmid (group 2) from 35 days post-inoculation (dpi). Similarly, the neutralizing efficacy of sera from group 3 was markedly enhanced compared with group 1 and group 2. In cellular immunity, the ratio of CD3(+)CD4(+)/CD3(+)CD8(+) T lymphocyte subpopulations from group 3 monitored by flow cytometry (FCM) was significantly higher than those from group1 and group 2 from 42?dpi to 21 days post-challenge (dpc). After viral challenge, pigs in group 3 showed significantly lower virus loads in peripheral blood measured by a real-time quantitative PCR (RT-qPCR), as compared with those in group 1 and group 2. Pigs in group 1 and group 2 had a low fever and displayed mild inappetence, lethargy, rough hair coats, and no lung lesions, while those in group 3 showed almost no clinical signs, no lung lesions. The scores of clinical signs of pigs in group 3 were significantly lower than those in both group 1 and group 2. Interestingly, the scores of lung lesions showed no significant differences among the three groups. Our results indicate that swine IL-4 markedly enhanced the protective immune response of pigs and improved the efficacy of the MLV in preventing PRRS disease.
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Gambogic Acid Induces Apoptosis in Imatinib-Resistant Chronic Myeloid Leukemia Cells via Inducing Proteasome Inhibition and Caspase-Dependent Bcr-Abl Downregulation.
Clin. Cancer Res.
PUBLISHED: 12-12-2013
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Chronic myelogenous leukemia (CML) is characterized by the constitutive activation of Bcr-Abl tyrosine kinase. Bcr-Abl-T315I is the predominant mutation that causes resistance to imatinib, cytotoxic drugs, and the second-generation tyrosine kinase inhibitors. The emergence of imatinib resistance in patients with CML leads to searching for novel approaches to the treatment of CML. Gambogic acid, a small molecule derived from Chinese herb gamboges, has been approved for phase II clinical trial for cancer therapy by the Chinese Food and Drug Administration (FDA). In this study, we investigated the effect of gambogic acid on cell survival or apoptosis in CML cells bearing Bcr-Abl-T315I or wild-type Bcr-Abl.EXPERIMENTAL DESIGN: CML cell lines (KBM5, KBM5-T315I, and K562), primary cells from patients with CML with clinical resistance to imatinib, and normal monocytes from healthy volunteers were treated with gambogic acid, imatinib, or their combination, followed by measuring the effects on cell growth, apoptosis, and signal pathways. The in vivo antitumor activity of gambogic acid and its combination with imatinib was also assessed with nude xenografts.RESULTS: Gambogic acid induced apoptosis and cell proliferation inhibition in CML cells and inhibited the growth of imatinib-resistant Bcr-Abl-T315I xenografts in nude mice. Our data suggest that GA-induced proteasome inhibition is required for caspase activation in both imatinib-resistant and -sensitive CML cells, and caspase activation is required for gambogic acid-induced Bcr-Abl downregulation and apoptotic cell death.CONCLUSIONS: These findings suggest an alternative strategy to overcome imatinib resistance by enhancing Bcr-Abl downregulation with the medicinal compound gambogic acid, which may have great clinical significance in imatinib-resistant cancer therapy. Clin Cancer Res; 1-13. ©2013 AACR.
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[Isolation and expression profiling of transformer 2 gene in Aedes aegypti].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 11-26-2013
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To isolate, identify and analyze the sex-determining gene Transformer 2 (Aaetra2) of the major vector mosquito Aedes aegypti.
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Systematic review and meta-analysis of balloon angioplasty versus primary stenting in the infrapopliteal disease.
Vasc Endovascular Surg
PUBLISHED: 11-07-2013
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Objectives: We performed a systematic review and meta-analysis of comparing balloon angioplasty and primary stenting for symptomatic infrapopliteal disease to evaluate the clinical value of primary stenting in treating infrapopliteal diseases. Methods: Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were followed. PubMed (1984-present), ScienceDirect (1980-present), Embase (1990-present), and CBM (1988-present) databases were searched for relevant articles. Finally, 16 studies (published between 2001 and 2013) satisfying the inclusion criteria were identified. The outcome parameters were immediate technical success, 1-year primary patency rate, 1-year limb salvage rate, and 1-year target vessel revascularization (TVR)-free rate. Comparisons were made with balloon angioplasty and primary stenting, and based on the different types of stents, we divided the primary stent group into the bare metal stent (BMS) group and drug-eluting stent (DES) group. Results: A total of 3789 patients and 4339 limbs constituted our final study population. The technical success rate of balloon angioplasty was 92.29% (95% confidence interval [CI] 88.75%-94.78%). Only 2 study reported the technical failure rates as 4% and 5.2% in the primary stent group. The pooled estimates of 1-year primary patency and TVR-free rate were similarly low in the balloon angioplasty group and BMS group (primary patency: 57.65%, 95% CI 53.54%-61.67% vs 60.95%, 95% CI 48.31%-72.28%, P = .38; TVR-free rate: 73.41%, 95% CI 66.51%-80.08% vs 73.66%, 95% CI 63.58%-81.75%, P = .91). The pooled estimates of 1-year primary patency and TVR-free rate in DES group were 81.10% (95% CI 75.48%-85.67%) and 90.30% (95% CI 85.30%-93.73%), respectively, which were better than those of the BMS and balloon angioplasty groups (P < .001 for both). The pooled estimate of 1-year limb salvage in the balloon angioplasty, BMS, and DES groups was 88.61% (95% CI 85.01%-91.43%), 94.41% (95% CI 89.52%-97.1%), and 95.20% (95% CI 86.97%-98.33%), respectively (P < .001). The BMS and DES groups had higher limb salvage rates than the balloon angioplasty group (P < .001 for both comparisons). The rates of severe complications were low both in the balloon angioplasty and in the primary stent groups. Conclusion: Primary BMS implantation had no advantage over balloon angioplasty in reducing restenosis or revascularization for infrapopliteal disease. Primary DES implantation seems to be a promising treatment for focal infrapopliteal lesions. Publication bias could not be ruled out, and the results should be treated with caution.
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Experimental study on the all-fiberized continuous-wave ytterbium-doped laser operating near 980 nm.
Appl Opt
PUBLISHED: 10-03-2013
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All-fiberized continuous-wave Yb-doped fiber lasers operating near 980 nm are fabricated, and 1.73 W, 980 nm lasing is obtained. Moreover, the output properties of the 980 nm fiber laser are studied by experiment. It is demonstrated, for the first time to the best of our knowledge, that the output power curve versus the active fiber length experiences double-peak values, which are caused by the red shift of the lasing wavelength induced by the longitudinal-mode competition. It is also demonstrated that the pump threshold increases exponentially with the active fiber length. The relationship between the pump threshold and the optimum active fiber length is examined.
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TSP-1-1223 A/G Polymorphism as a Potential Predictor of the Recurrence Risk of Bladder Cancer in a Chinese Population.
Int J Genomics
PUBLISHED: 09-27-2013
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Backgrounds. TSP-1 is a glycoprotein that functions in the biology of bladder cancer. We investigated the relationship between the distribution of TSP-1-1223 A/G polymorphism (rs2169830) and the clinical characteristics of bladder cancer. Materials and Methods. TaqMan assay was performed to determine the genotype of 609 cases and 670 control subjects in a Chinese population. Logistic regression was used to assess the association between the polymorphism and the risk of bladder cancer. Quantitative real-time polymerase chain reaction was performed to determine TSP-1 mRNA expression. Survival curves were generated using the Kaplan-Meier method. Results. No significant differences were detected in the genotype frequencies of healthy control subjects and patients with bladder cancer. By contrast, the time until the first recurrence differed significantly between genotypes (P = 0.017). The expression of TSP-1 mRNA in bladder cancer tissues was lower in patients with an AG genotype than in those with an AA genotype. The lowest expression was observed in patients with a GG genotype. Conclusions. In conclusion, TSP-1-1223 A/G polymorphism may contribute to the recurrence of bladder cancer in Chinese population.
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The combination of proteasome inhibitors bortezomib and gambogic acid triggers synergistic cytotoxicity in vitro but not in vivo.
Toxicol. Lett.
PUBLISHED: 09-23-2013
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The proteasome inhibitor-based combinational therapy has been reported to be an efficient cancer treatment. Our recent studies demonstrated that the natural compound gambogic acid (GA) is a tissue-specific proteasome inhibitor, comparable to bortezomib (Bor), and sensitizes malignant cells to the proteasome inhibitor MG132/MG262 both in vitro and in vivo. The aim of this study was to further extend our investigation by combining GA with the clinically used proteasome inhibitor Bor to test their combined efficacy against human hepatoma HepG2 and mouse hepatoma H22 cells. GA and Bor synergistically induced cytotoxicity and cell death in human HepG2 and mouse H22 cells, and accelerated proteasome inhibition, endoplasmic reticulum (ER) stress and caspase activation in HepG2 cancer cells. However, unexpectedly, GA did not enhance or even antagonized Bor-induced tumor growth inhibition in H22 allograft and HepG2 xenograft tumor models. These findings demonstrated that GA increased Bor activity in vitro but limited the efficacy of Bor in vivo. We suggest that the combination of GA and Bor be avoided when administering these drugs to patients.
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Green Tea Polyphenols Alleviate Obesity in Broiler Chickens through the Regulation of Lipid-Metabolism-Related Genes and Transcription Factor Expression.
J. Agric. Food Chem.
PUBLISHED: 08-30-2013
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The current study investigated the effects of green tea polyphenols (GTPs) on lipid metabolism and its mechanisms using broiler chickens ( Gallus gallus domesticus ). A total of 36 male chickens (35 days old) had been subjected to an oral administration of GTPs at a dosage of 0, 50 (low), and 100 (high) mg/kg of body weight for 20 days. Our results showed that GTPs significantly decreased the abdominal and subcutaneous fat masses of broilers and reduced the serum triglyceride, total cholesterol, and low-density lipoprotein cholesterol levels compared to those of the control. Furthermore, the expression levels for lipid anabolism genes were significantly downregulated, while the expression levels of fat transportation and catabolism-related genes, carnitine palmitoyl transferase I (CPT-I), acyl-CoA oxidase 1 (ACOX1), and peroxisome proliferator-activated receptor-? (PPAR?) in liver, adipose triglyceride lipase (ATGL) in abdominal fat, and lipoprotein lipase (LPL) in skeletal muscles, were notably upregulated. Our data have revealed that GTPs alleviate obesity and serum lipid levels in broiler chickens by suppressing fatty acid synthesis and stimulating lipolysis.
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Synthesis of highly substituted 4H-pyrido[1,2-a]pyrimidines via a one-pot three-component condensation reaction.
ACS Comb Sci
PUBLISHED: 08-22-2013
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A one-pot three-component reaction, involving condensation of 2-aminopyridines, aldehydes, and ketones/aldehydes under trifluoromethanesulfonic acid catalysis, provides rapid access to highly substituted novel 4H-pyrido[1,2-a]pyrimidines.
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Peroxiredoxin 2 is upregulated in colorectal cancer and contributes to colorectal cancer cells survival by protecting cells from oxidative stress.
Mol. Cell. Biochem.
PUBLISHED: 08-21-2013
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Peroxiredoxin 2 (Prdx2) is a member of the peroxiredoxin family, which is responsible for neutralizing reactive oxygen species. Prdx2 has been found to be elevated in several human cancer cells and tissues, including colorectal cancer (CRC), and it influences diverse cellular processes involving cells survival, proliferation, and apoptosis, which suggests a possible role for Prdx2 in the maintenance of cancer cell. However, the mechanism by which Prdx2 modulates CRC cells survival is unknown. The current study aimed to determine the effect of elevated Prdx2 on CRC cells and to further understand the underlying mechanisms. The results of this study showed that Prdx2 was upregulated in CRC tissues compared with the matched noncancer colorectal mucosa tissues and that Prdx2 expression was positively associated with tumor metastasis and the TNM stage. In the LoVo CRC cell line, Prdx2 was upregulated at both the RNA and protein levels compared with the normal FHC colorectal mucosa cell line. In addition, the LoVo CRC cell line was significantly more resistant to hydrogen peroxide (H2O2)-induced apoptosis because of a failure to activate pro-apoptotic pathways in contrast to Prdx2 knockdown cells. Suppression of Prdx2 using a lentiviral vector-mediated Prdx2-specific shRNA in the LoVo cell line restored H2O2 sensitivity. Our results suggested that Prdx2 has an essential role in regulating oxidation-induced apoptosis in CRC cells. Prdx2 may have potential as a therapeutic target in CRC.
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Calcium channel blocker verapamil accelerates gambogic acid-induced cytotoxicity via enhancing proteasome inhibition and ROS generation.
Toxicol In Vitro
PUBLISHED: 08-04-2013
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Verapamil (Ver), an inhibitor of the multidrug resistance gene product, has been proved to be a promising combination partner with other anti-cancer agents including proteasome inhibitor bortezomib. Gambogic acid (GA) has been approved for Phase II clinical trials in cancer therapy in China. We have most recently reported that GA is a potent proteasome inhibitor, with anticancer efficiency comparable to bortezomib but much less toxicity. In the current study we investigated whether Ver can enhance the cytotoxicity of GA. We report that (i) the combination of Ver and GA results in synergistic cytotoxic effect and cell death induction in HepG2 and K562 cancer cell lines; (ii) a combinational treatment with Ver and GA induces caspase activation, endoplasmic reticulum (ER) stress and reactive oxygen species (ROS) production; (iii) caspase inhibitor z-VAD blocks GA+Ver-induced apoptosis but not proteasome inhibition; (iv) cysteine-containing compound N-acetylcysteine (NAC) prevents GA+Ver-induced poly(ADP-ribose) polymerase cleavage and proteasome inhibition. These results demonstrate that Ver accelerates GA-induced cytotoxicity via enhancing proteasome inhibition and ROS production. These findings indicate that the natural product GA is a valuable candidate that can be used in combination with Ver, thus representing a compelling anticancer strategy.
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HSP70 and modified HPV 16 E7 fusion gene without the addition of a signal peptide gene sequence as a candidate therapeutic tumor vaccine.
Oncol. Rep.
PUBLISHED: 08-02-2013
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Millions of women are currently infected with high-risk human papillomavirus (HPV), which is considered to be a major risk factor for cervical cancer. Thus, it is urgent to develop therapeutic vaccines to eliminate the established infections or HPV-related diseases. In the present study, using the mycobacterium tuberculosis heat shock protein 70 (MtHSP70) gene linked to the modified HPV 16 E7 (mE7) gene, we generated two potential therapeutic HPV DNA vaccines, mE7/MtHSP70 and SigmE7/MtHSP70, the latter was linked to the signal peptide gene sequence of human CD33 at the upstream of the fusion gene. We found that vaccination with the mE7/MtHSP70 DNA vaccine induced a stronger E7-specific CD8+ T cell response and resulted in a more significant therapeutic effect against E7-expressing tumor cells in mice. Our results demonstrated that HSP70 can play a more important role in mE7 and MtHSP70 fusion DNA vaccine without the help of a signal peptide. This may facilitate the use of HSP70 and serve as a significant reference for future study.
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Peroxiredoxin 2 knockdown by RNA interference inhibits the growth of colorectal cancer cells by downregulating Wnt/?-catenin signaling.
Cancer Lett.
PUBLISHED: 07-31-2013
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Peroxiredoxin 2 (Prdx2) has been shown to act as an antioxidant whose main function is to reduce hydrogen peroxide (H2O2) in cells, and Prdx2 is abnormally elevated in colorectal cancer (CRC). However, the functional significance of this up-regulation and the detailed molecular mechanism behind the regulatory effect of Prdx2 on the growth of CRC cells have not been elucidated. In this study, we demonstrated that Prdx2 knockdown using a lentiviral vector-mediated specific shRNA inhibited cell growth, stimulated apoptosis, and augmented the production of endogenous reactive oxygen species (ROS). Further, silencing of Prdx2 resulted in an altered expression of proteins associated with the Wnt signaling pathway. Finally, Prdx2 knockdown contributed to attenuated CRC growth in BALB/c nude mice. In conclusion, these findings demonstrate that the regulatory effects of Prdx2 can be partially attributed to Wnt/?-catenin signaling.
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Essential hypertension treated by wuling powder and modified tianma gouteng decoction: A cohort study without controls.
Complement Ther Med
PUBLISHED: 07-24-2013
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To evaluate the efficacy and safety of wuling powder and modified tianma gouteng decoction as an open add-on therapy for treating essential hypertension (EH).
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The COP9 signalosome is required for autophagy, proteasome-mediated proteolysis, and cardiomyocyte survival in adult mice.
Circ Heart Fail
PUBLISHED: 07-19-2013
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The COP9 signalosome (CSN) is an evolutionarily conserved protein complex composed of 8 unique protein subunits (CSN1 through CSN8). We have recently discovered in perinatal mouse hearts that CSN regulates not only proteasome-mediated proteolysis but also macroautophagy. However, the physiological significance of CSN in a post-mitotic organ of adult vertebrates has not been determined. We sought to study the physiological role of CSN8/CSN in adult mouse hearts.
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Excellent toluene sensing properties of SnO2-Fe2O3 interconnected nanotubes.
ACS Appl Mater Interfaces
PUBLISHED: 06-24-2013
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SnO2-Fe2O3 interconnected nanotubes were obtained by combining the single nozzle electrospinning and thermal treatment methods. The results of scanning electron microscopy revealed the special structure of ruptures and interconnected nanotubes in the as-prepared materials. The toluene sensing test results of SnO2-Fe2O3 interconnected nanotubes show that SnO2-Fe2O3 interconnected nanotubes possess excellent toluene gas-sensing properties. The sensitivity of detecting limit (50 ppb) is 2.0 at the optimum operating temperature of 260 °C. The response and recovery times to 1 ppm toluene are about 5 and 11 s, respectively. Moreover, the SnO2-Fe2O3 interconnected nanotube gas sensors exhibit the remarkable selectivity to toluene, and good long-term stability.
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Investigation on the interaction between endocrine disruptor triphenyltin with human serum albumin.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 06-20-2013
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The interaction between triphenyltin (TPT) and human serum albumin (HSA) in physiological buffer (pH=7.4) was investigated by the fluorescence quenching technique. The results of fluorescence titration revealed that TPT could strongly quench the intrinsic fluorescence of HSA through a static quenching procedure. The apparent binding constants K and number of binding sites n of TPT with HSA were 2.51×10(3) and 0.96 at 298K which were obtained by the fluorescence quenching method. The thermodynamic parameters enthalpy change (?H), entropy change (?S) were positive, which indicated that the interaction of TPT with HSA was driven mainly by hydrophobic forces. The process of binding was a spontaneous process in which Gibbs free energy change was negative. The distance r between donor (HSA) and acceptor (TPT) was calculated to be 3.13nm based on Forsters non-radiative energy transfer theory. The results of synchronous fluorescence, three-dimensional fluorescence and circular dichroism (CD) spectra showed that the triphenyltin induced conformational changes of HSA.
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The Cytochrome P4501A1 gene polymorphisms and idiopathic male infertility risk: A meta-analysis.
Gene
PUBLISHED: 05-23-2013
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Studies of the relationship between male infertility and CYP1A1 polymorphisms are inconclusive. To drive a more precise estimation, we performed a meta-analysis based on 1060cases and 1225 controls from 7 published case-control studies. PubMed and CNKI literature search were conducted to identify all eligible studies investigating such a relationship. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association in the additive model, dominant model, recessive model, and allele-frequency genetic model. In the overall analysis, the frequency of CYP1A1*2A genotype was significantly associated with susceptibility to idiopathic male infertility. Further stratified analysis by ethnicity showed notable association between the polymorphism and the risk of idiopathic male infertility in Asians. In conclusion, these results support that the CYP1A1*2A genotype polymorphism mainly contributes to idiopathic male infertility susceptibility in Asians but not in Caucasians.
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Topochemical transformation route to atomically thick Co3O4 nanosheets realizing enhanced lithium storage performance.
Nanoscale
PUBLISHED: 05-08-2013
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We first demonstrate the rational design and fabrication of novel atomically thick Co3O4 nanosheets (ATCNs) with a specific facet exposed by topochemical transformation from layered intermediate precursors to optimize energy storage. The eminently enhanced lithium storage performance can be attributed not only to the synergistic advantages of inorganic graphene analogues but also the increase of Co(2+) atoms and charge redistribution for ATCNs, which were first revealed by means of synchrotron radiation X-ray absorption near-edge spectroscopy. This work opens the window for the preparation of non-layered atomically thick nanosheets, which will significantly enrich the species of inorganic graphene analogues and optimize energy storage by reasonable materials design and fabrication.
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Formation and characterization of silver nanoparticles in aqueous solution via ultrasonic irradiation.
Ultrason Sonochem
PUBLISHED: 04-30-2013
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In this study, a simple and green method to synthesize silver nanoparticles (Ag NPs) in aqueous solution via ultrasonic irradiation has been developed. Ultrafine Ag NPs with average diameter of 8nm were obtained through sonicating aqueous solution of sodium hydroxide (NaOH, 0.1mM) with adding silver nitrate solution (AgNO3, 5.88mM) drop by drop. In pure aqueous solution, the reactive route related to hydroxyl radicals (OH) is presented. Furthermore, in alkaline aqueous solution, the effects of hydroxyl ions (OH(-)) on formation of Ag NPs are discussed detailedly. The formation of Ag NPs was tracked by surface plasmon resonance (SPR) band of ultraviolet-visible (UV-Vis) spectrum; the morphology of the obtained Ag NPs was characterized through transmission electron microscopy (TEM); energy dispersive X-ray spectroscopy (EDX) and X-ray powder diffraction (XRD) confirmed the formation of metallic Ag NPs.
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PD-L1 Blockade Attenuated Sepsis-Induced Liver Injury in a Mouse Cecal Ligation and Puncture Model.
Mediators Inflamm.
PUBLISHED: 04-29-2013
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Liver plays a major role in hypermetabolism and produces acute phase proteins during systemic inflammatory response syndrome and it is of vital importance in host defense and bacteria clearance. Our previous studies indicated that programmed death-1 (PD-1) and its ligand programmed death ligand-1 (PD-L1) are crucial modulators of host immune responses during sepsis. Our current study was designed to investigate the role of PD-L1 in sepsis-induced liver injury by a mouse cecal ligation and puncture (CLP) model. Our results indicated that there was a significant increase of PD-L1 expression in liver after CLP challenge compared to sham-operated controls, in terms of levels of mRNA transcription and immunohistochemistry. Anti-PD-L1 antibody significantly alleviated the morphology of liver injury in CLP mice. Anti-PD-L1 antibody administration decreased ALT and AST release in CLP mice, decreased the levels of tumor necrosis factor (TNF)- ? , interleukin (IL)-6, and IL-10 mRNA in liver after sepsis challenge. Thus, anti-PD-L1 antibody might have a therapeutic potential in attenuating liver injury in sepsis.
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Dendrimer-stabilized bismuth sulfide nanoparticles: synthesis, characterization, and potential computed tomography imaging applications.
Analyst
PUBLISHED: 04-26-2013
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We report here a general approach to synthesizing dendrimer-stabilized bismuth sulfide nanoparticles (Bi2S3 DSNPs) for potential computed tomography (CT) imaging applications. In this study, ethylenediamine core glycidol hydroxyl-terminated generation 4 poly(amidoamine) dendrimers (G4.NGlyOH) were used as stabilizers to first complex the Bi(III) ions, followed by reaction with hydrogen sulfide to generate Bi2S3 DSNPs. By varying the molar ratio of Bi atom to dendrimer, stable Bi2S3 DSNPs with an average size range of 5.2-5.7 nm were formed. The formed Bi2S3 DSNPs were characterized via different techniques. X-ray absorption coefficient measurements show that the attenuation of Bi2S3 DSNPs is much higher than that of iodine-based CT contrast agent at the same molar concentration of the active element (Bi versus iodine). 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability assay and hemolysis assay reveal that the formed Bi2S3 DSNPs are noncytotoxic and have a negligible hemolysis effect in the studied concentration range. Furthermore, we show that cells incubated with the Bi2S3 DSNPs are able to be imaged using CT, a prominent enhancement at the point of rabbit injected subcutaneously with the Bi2S3 DSNPs is able to be visualized via CT scanning, and the mouses pulmonary vein can be visualized via CT after intravenous injection of the Bi2S3 DSNPs. With the good biocompatibility, enhanced X-ray attenuation property, and tunable dendrimer chemistry, the designed Bi2S3 DSNPs should be able to be further functionalized, allowing them to be used as a highly efficient contrast agent for CT imaging of different biological systems.
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Functional characterization of three MicroRNAs of the Asian tiger mosquito, Aedes albopictus.
Parasit Vectors
PUBLISHED: 04-24-2013
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Temporal and stage specific expression of microRNAs (miRNAs) in embryos, larvae, pupae and adults of Aedes albopictus showed differential expression levels across the four developmental stages, indicating their potential regulatory roles in mosquito development. The functional characterization of these miRNAs was not known. Accordingly our study evaluated the functional characterization of three miRNAs, which are temporally up-regulated in the various developmental stages of Ae. albopictus mosquitoes.
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Species persistence in landscapes with spatial variation in habitat quality: a pair approximation model.
J. Theor. Biol.
PUBLISHED: 04-18-2013
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Habitat degradation has become a major threat to species persistence. Although several models have explicitly integrated habitat quality into metapopulation dynamics, we still lack knowledge of the spatial variability of species persistence which may result from the clustering of habitat patches of differing quality. Here we construct both pair approximation (PA) and cellular automaton (CA) models for species persistence in homogeneous versus heterogeneous landscapes. Heterogeneous landscapes are generated by varying the orthogonal-neighbour correlation between two different-quality habitats. In our simulations, the PA model exhibits similar population dynamics to the CA model, though it overestimates species persistence due to the doublet approximation neglecting correlation beyond nearest neighbours. Generally, landscape heterogeneity enhances species persistence relative to landscape homogeneity, especially with enlarging habitat-quality difference. This indicates that models based on homogeneous landscapes may overestimate species extinction rate. In heterogeneous landscapes, habitat clumping does not influence global dispersers because of random establishment, although it does promote the persistence of local dispersers, especially under severe habitat degradation. However, habitat configurational fragmentation improves the persistence of global dispersers that are highly sensitive to local crowding, probably by reducing density dependence, but this positive fragmentation effect on local dispersers is overshadowed by the stronger negative border effect on impeding local extension. Furthermore, increasing density dependence promotes the extinction risk of local dispersers, while global dispersers are not influenced. For conservation and habitat management, our results suggest that minimising random anthropogenic disturbance should take priority over increasing the connectivity of good-quality habitat, as random habitat degradation poses a more serious threat to species persistence than clustered habitat degradation. Owing to species diverse responses to habitat configurational fragmentation, landscapes with different properties may accommodate different species.
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Design, synthesis and biological evaluation of enzymatically cleavable NSAIDs prodrugs derived from self-immolative dendritic scaffolds for the treatment of inflammatory diseases.
Bioorg. Med. Chem.
PUBLISHED: 04-01-2013
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It has been reported that delivery systems based on dendritic prodrugs of Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) improved the properties of drug molecules and reduced the side effects and irritation on the gastric mucosa. To find a more effective way in NSAIDs dendritic prodrugs, in this paper, three different dendritic scaffolds of enzymatically cleavable naproxen conjugates have been synthesized in a convergent approach and well characterized by NMR and MS techniques. These self-immolative dendritic NISADs prodrugs programmed to release multiple molecules of the potent naproxen after a single enzymatic activation step, and in 50% human plasma, the drug released from the compound T3 reaching 47.3% after 24h in vitro assay. Moreover, all prodrugs were also found to maintain more significant anti-inflammatory activity, no significant cytotoxicity against HEK293 cells and less degree of ulcerogenic potential in vivo than their monomeric counterpart naproxen. These results provided an effective entry to the development of new dendritic NSAIDs prodrugs.
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Annexin A3 is associated with a poor prognosis in breast cancer and participates in the modulation of apoptosis in vitro by affecting the Bcl-2/Bax balance.
Exp. Mol. Pathol.
PUBLISHED: 03-21-2013
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Annexins are a family of intracellular proteins that bind membrane phospholipids in a Ca(2+) concentration-dependent manner. Several annexins play important roles during tumor progression. However, little is known about the clinical implications and biological functions of Annexin A3 in breast cancer.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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