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Find video protocols related to scientific articles indexed in Pubmed.
Ischemic stroke associated with immune thrombocytopenia.
J. Thromb. Thrombolysis
PUBLISHED: 11-09-2014
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The objective of this study was to review all cases in literature in which the clinical manifestations of ischemic stroke and immune thrombocytopenia (ITP) were presented in the same patient including a new case of our own and discuss the possible mechanism and management of this syndrome. We reviewed 12 reports in which 18 cases were diagnosed as ischemic stroke and ITP. The clinical manifestations and ischemic lesion patterns of the 18 cases and our new case were analyzed in detail to elucidate the characteristics and management of this kind of syndrome. Of all the cases, 8 females and 10 males, 10 of them were Koreans; 3 were Americans; 3 were Japanese; 1 was British and 1 was Australian. The age of eight patients was no more than 50 years old. Most of them had a low platelet count. CT and/or MRI of brain were seen in all tested cases. Prognosis of ischemic stroke was good in 18 of the 19 patients. Although extremely rare, ischemic stroke and ITP may present in the same patient with variant characteristics. This paradoxical mechanism and management of ischemic stroke associated with ITP requires further investigation.
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A three-dimensional hierarchical TiO2 urchin as a photoelectrochemical anode with omnidirectional anti-reflectance properties.
Phys Chem Chem Phys
PUBLISHED: 09-25-2014
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In this communication, we report an innovative electrode design of 3D hierachical TiO2 urchin assembled with a hollow TiO2 spheres core and radial TiO2 nanorod shell prepared via a facile colloid template route combined with atomic layer deposition and a hydrothermal growth process. The periodically hierarchical TiO2 urchin exhibits excellent omnidirectional anti-reflectance properties in a wide range of wavelengths and angles of incidence (AOI). When tested as a photoanode for PEC water splitting, a greatly improved photoelectrochemical water splitting performance is obtained in comparison to that of TiO2 microspheres due to the improved light harvesting and charge collection efficiency.
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Enhanced Photoelectrochemical Water Splitting Performance of Anodic TiO2 Nanotube Arrays by Surface Passivation.
ACS Appl Mater Interfaces
PUBLISHED: 09-22-2014
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One-dimensional anodic titanium oxide nanotube (TONT) arrays provide a direct pathway for charge transport, and thus hold great potential as working electrodes for electrochemical energy conversion and storage devices. However, the prominent surface recombination due to the large amount surface defects hinders the performance improvement. In this work, the surface states of TONTs were passivated by conformal coating of high-quality Al2O3 onto the tubular structures using atomic layer deposition (ALD). The modified TONT films were subsequently employed as anodes for photoelectrochemical (PEC) water splitting. The photocurrent (0.5 V vs Ag/AgCl) recorded under air mass 1.5 global illumination presented 0.8 times enhancement on the electrode with passivation coating. The reduction of surface recombination rate is responsible for the substantially improved performance, which is proposed to have originated from a decreased interface defect density in combination with a field-effect passivation induced by a negative fixed charge in the Al2O3 shells. These results not only provide a physical insight into the passivation effect, but also can be utilized as a guideline to design other energy conversion devices.
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System-wide characterization of bZIP transcription factor proteins involved in infection-related morphogenesis of Magnaporthe oryzae.
Environ. Microbiol.
PUBLISHED: 09-04-2014
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The basic leucine zipper (bZIP) domain-containing transcription factors (TFs) function as key regulators of cellular growth and differentiation in eukaryotic organisms including fungi. We have previously identified MoAp1 and MoAtf1 as bZIP TFs in Magnaporthe oryzae and demonstrated that they regulate the oxidative stress response and are critical in conidiogenesis and pathogenicity. Studies of bZIP proteins could provide a novel strategy for controlling rice blast, but a systematic examination of the bZIP proteins has not been carried out. Here, we identified 19 additional bZIP TFs and characterized their functions. We found that the majority of these TFs exhibit active functions, most notably, in conidiogenesis. We showed that MoHac1 regulates the endoplasmic reticulum stress response through a conserved unfolded protein response pathway, MoMetR controls amino acid metabolism to govern growth and differentiation, and MoBzip10 governs appressorium function and invasive hyphal growth. Moreover, MoBzip5 participates in appressorium formation through a pathway distinct from that MoBzip10, and MoMeaB appears to exert a regulatory role through nutrient uptake and nitrogen utilization. Collectively, our results provide insights into shared and specific functions associated with each of these TFs and link the regulatory roles to the fungal growth, conidiation, appressorium formation, host penetration and pathogenicity.
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'Functional' inspiratory and core muscle training enhances running performance and economy.
J Strength Cond Res
PUBLISHED: 08-26-2014
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We compared the effects of two 6-week high-intensity interval training interventions. Under the control condition (CON), only interval training was undertaken, whilst under the intervention condition (ICT), interval training sessions were followed immediately by core training, which was combined with simultaneous inspiratory muscle training - 'functional' IMT. Sixteen recreational runners were allocated to either ICT or CON groups. Prior to the intervention phase, both groups undertook a 4-week programme of 'foundation' IMT to control for the known ergogenic effect of IMT [30 inspiratory efforts at 50% maximal static inspiratory pressure (P0) per set, 2 sets.d, 6 d.wk]. The subsequent 6-week interval running training phase, consisted of 3-4 sessions.wk. In addition, the ICT group undertook four inspiratory-loaded core exercises [10 repetitions.set, 2 sets.d, inspiratory load set at 50% post-IMT P0] immediately after each interval training session. The CON group received neither core training nor functional IMT. Following the intervention phase, global inspiratory and core muscle functions increased in both groups (P<0.05), as evidenced by P0 and a sport-specific endurance plank test performance (SEPT), respectively. Compared to CON, the ICT group showed larger improvements in SEPT, running economy at the speed of the OBLA, and 1-hr running performance (3.04% vs 1.57%, P<0.05). The changes in these variables were inter-individually correlated (r?0.57, n=16, P<0.05). Such findings suggest that the addition of inspiratory-loaded core conditioning into a high-intensity interval training program augments the influence of the interval program upon endurance running performance, and that this may be underpinned by an improvement in running economy.
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Puerarin protects hippocampal neurons against cell death in pilocarpine-induced seizures through antioxidant and anti-apoptotic mechanisms.
Cell. Mol. Neurobiol.
PUBLISHED: 08-24-2014
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Puerarin extracted from Radix puerariae has been shown to exert neuroprotective effects. However, it is still not known whether puerarin protects hippocampal neurons against cell death in pilocarpine-induced seizures. In this study, we found that pretreatment with puerarin significantly attenuated the neuronal death in the hippocampus of rats with pilocarpine-induced epilepsy. In addition, puerarin decreased the level of seizure-induced reactive oxygen species in mitochondria isolated from the rat hippocampi. Terminal deoxyuridine triphosphate nick-end labeling staining showed that puerarin exerted an anti-apoptotic effect on the neurons in the epileptic hippocampus. Western blot analysis showed that puerarin treatment significantly decreased the expression of Bax and increased the expression of Bcl-2. Moreover, puerarin treatment restored the altered mitochondrial membrane potential and cytochrome c release from the mitochondria in the epileptic hippocampi. Altogether, the findings of this study suggest that puerarin exerts a therapeutic effect on epilepsy-induced brain injury through antioxidant and anti-apoptotic mechanisms.
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Two doses of botulinum toxin type A for the treatment of trigeminal neuralgia: observation of therapeutic effect from a randomized, double-blind, placebo-controlled trial.
J Headache Pain
PUBLISHED: 08-17-2014
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In the majority of cases, trigeminal neuralgia (TN) is a unilateral condition with ultra-short stabbing pain located along one or more branches of the trigeminal nerve. Although prophylactic pharmacological treatment is first choise, considering of insufficient effect or unacceptable side effects, neurosurgical treatment or lesion treatment should be considered. In addition to all these procedures mentioned above, one approach has been based on local intradermal and/or submucosal injections of Botulinum Toxin Type A (BTX-A).
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Impact of sludge cation distribution pattern on its filterability in membrane bioreactor.
Bioresour. Technol.
PUBLISHED: 08-15-2014
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The distributions of cations of various valences (Na(+), Ca(2+) and Fe(3+)) in the outer layers of extracellular polymeric substances (EPSs) to pellet have a significant impact on the stratification structure of polysaccharides (PS) or proteins (PN) in activated sludge. Comparison with the control showed that the monovalent Na(+) reduced flocculability slightly (about 9.75%), whereas Ca(2+) and Fe(3+) increased flocculability significantly. The modified fouling index (MFI) had a significant correlation with PN in the supernatant (rp=0.8593), slime (rp=0.7218) and loosely bound EPS (LB, rp=0.8012). However, it had a moderate correlation with PS in supernatant (rp=0.5842), and weak correlation to slime (rp=0.3785) or LB (rp=0.3219). There was an ignored correlation with PN or PS in the tightly bound EPS (TB) or pellet. The lower amount of PN or PS in the supernatant would have positive impact on improving the activated sludge filterability.
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Impaired Adiponectin Signaling Contributes to Disturbed Catabolism of Branched-Chain Amino Acids in Diabetic Mouse.
Diabetes
PUBLISHED: 07-30-2014
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The branched-chain amino acids (BCAA) accumulated in type 2 diabetes mellitus are independent contributors to insulin resistance. The activity of branched-chain ?-keto acid dehydrogenase (BCKD) complex, rate-limiting enzyme in BCAA catabolism, is reduced in diabetic states, which contributes to elevated BCAA concentrations. However, the mechanisms underlying decreased BCKD activity remain poorly understood. Here we demonstrate that mitochondrial phosphatase 2C (PP2Cm), a newly identified BCKD phosphatase which increases BCKD activity, was significantly down-regulated in ob/ob and type 2 diabetic mice. Interestingly, in adiponectin knockout (APN(-/-)) mice fed with high-fat-diet (HD), PP2Cm expression and BCKD activity were significantly decreased, whereas BCKD kinase (BDK) which inhibits BCKD activity was markedly increased. Concurrently, plasma BCAA and branched-chain ?-keto acids (BCKA) were significantly elevated. APN treatment markedly reverted PP2Cm, BDK, BCKD activity, BCAA and BCKA levels in HD-fed APN(-/-) and diabetic animals. Additionally, increased BCKD activity caused by APN administration was partially but significantly inhibited in PP2Cm knockout mice. Finally, APN-mediated up-regulation of PP2Cm expression and BCKD activity were abolished when adenosine monophosphate-activated protein kinase (AMPK) was inhibited. Collectively, we have provided the first direct evidence that APN is a novel regulator of PP2Cm and systematic BCAA levels, suggesting that targeting APN may be a pharmacological approach to ameliorating BCAA catabolism in the diabetic state.
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Large-area ordered P-type Si nanowire arrays as photocathode for highly efficient photoelectrochemical hydrogen generation.
ACS Appl Mater Interfaces
PUBLISHED: 07-23-2014
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In this Article, we report the successful fabrication of large-area ordered Si nanowire arrays (NWAs) by a cost-effective and scalable wet-etching process in combination with nanospheres lithography technique. The periodical Si NWAs are further investigated as photocathode for water splitting, with excellent hydrogen evolution performances with a maximum photocurrent density of 27 mA cm(-2) achieved, which is ?2.5 times that of planar Si and random Si nanowires electrode. The greatly improved PEC performance can be attributed to the patterned and ordered NWs structure as a result of enhancement of the light harvesting as well as charge transportation and collection efficiency.
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Cloning, characterization, and production of a novel lysozyme by different expression hosts.
J. Microbiol. Biotechnol.
PUBLISHED: 07-03-2014
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Lysozyme is a protein found in egg white, tears, saliva, and other secretions. As a marketable natural alternative to preservatives, lysozyme can act as a natural antibiotic. In this study, we have isolated Bacillus licheniformis TIB320 from soil, which contains a lysozyme gene with various features. We have cloned and expressed the lysozyme in E. coli. The antimicrobial activity of the lysozyme showed that it had a broad antimicrobial spectrum against several standard strains. The lysozyme could maintain efficient activities in a pH range between 3 and 9 and from 20°C to 60°C, respectively. The lysozyme was resistant to pepsin and trypsin to some extent at 40°C. Production of the lysozyme was optimized by using various expression strategies in B. subtilis WB800. The lysozyme from B. licheniformis TIB320 will be promising as a food or feed additive.
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Responsive immunization and intervention for infectious diseases in social networks.
Chaos
PUBLISHED: 07-03-2014
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By using the microscopic Markov-chain approximation approach, we investigate the epidemic spreading and the responsive immunization in social networks. It is assumed that individual vaccination behavior depends on the local information of an epidemic. Our results suggest that the responsive immunization has negligible impact on the epidemic threshold and the critical value of initial epidemic outbreak, but it can effectively inhibit the outbreak of epidemic. We also analyze the influence of the intervention on the disease dynamics, where the vaccination is available only to those individuals whose number of neighbors is greater than a certain value. Simulation analysis implies that the intervention strategy can effectively reduce the vaccine use under the epidemic control.
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[Effect of grain-bean package, grain-bean package dietary fiber and single whole grain dietary fiber on dyslipidemia rats].
Wei Sheng Yan Jiu
PUBLISHED: 06-27-2014
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To observe and compare the effects of grain-bean package, dietary fiber (DF) extracted from grain-bean package, and DF from grain corn on the blood lipids and fatty acid synthase (FAS) activity in high-fat, high-cholesterol feeding induced dyslipidemia rats, and observe its effects on regulation of sterol regulatory element protein-1c (SREBP-1c) mRNA expression in rat liver.
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Ror2 receptor mediates Wnt11 ligand signaling and affects convergence and extension movements in zebrafish.
J. Biol. Chem.
PUBLISHED: 06-13-2014
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The receptor-tyrosine kinase Ror2 acts as an alternative receptor or co-receptor for Wnt5a and mediates Wnt5a-induced convergent extension movements during embryogenesis in mice and Xenopus as well as the polarity and migration of several cell types during development. However, little is known about whether Ror2 function is conserved in other vertebrates or is involved in other non-canonical Wnt ligands in vivo. In this study we demonstrated that overexpression of dominant-negative ror2 (ror2-TM) mRNA in zebrafish embryos resulted in convergence and extension defects and incompletely separated eyes, which is consistent with observations from slb/wnt11 mutants or wnt11 knockdown morphants. Moreover, the co-injection of ror2-TM mRNA and a wnt11 morpholino or the coexpression of ror2 and wnt11 in zebrafish embryos synergetically induced more severe convergence and extension defects. Transplantation studies further demonstrated that the Ror2 receptor responded to the Wnt11 ligand and regulated cell migration and cell morphology during gastrulation. DnRor2 inhibited the action of Wnt11, which was revealed by a decreased percentage of Wnt11-induced convergence and extension defects. Ror2 physically interacts with Wnt11. Theintracellular Tyr-647andSer-863 sites ofRor2are essential for mediating the action of Wnt11. Dishevelled and RhoA act downstream of Wnt11-Ror2 to regulate convergence and extension movements. Overall, our data suggest an important role of Ror2 in mediating Wnt11 signaling and in regulating convergence and extension movements in zebrafish.
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Melatonin receptor-mediated protection against myocardial ischemia/reperfusion injury: role of SIRT1.
J. Pineal Res.
PUBLISHED: 06-10-2014
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Melatonin confers cardioprotective effect against myocardial ischemia/reperfusion (MI/R) injury by reducing oxidative stress. Activation of silent information regulator 1 (SIRT1) signaling also reduces MI/R injury. We hypothesize that melatonin may protect against MI/R injury by activating SIRT1 signaling. This study investigated the protective effect of melatonin treatment on MI/R heart and elucidated its potential mechanisms. Rats were exposed to melatonin treatment in the presence or the absence of the melatonin receptor antagonist luzindole or SIRT1 inhibitor EX527 and then subjected to MI/R operation. Melatonin conferred a cardioprotective effect by improving postischemic cardiac function, decreasing infarct size, reducing apoptotic index, diminishing serum creatine kinase and lactate dehydrogenase release, upregulating SIRT1, Bcl-2 expression and downregulating Bax, caspase-3 and cleaved caspase-3 expression. Melatonin treatment also resulted in reduced myocardium superoxide generation, gp91(phox) expression, malondialdehyde level, and increased myocardium superoxide dismutase (SOD) level, which indicate that the MI/R-induced oxidative stress was significantly attenuated. However, these protective effects were blocked by EX527 or luzindole, indicating that SIRT1 signaling and melatonin receptor may be specifically involved in these effects. In summary, our results demonstrate that melatonin treatment attenuates MI/R injury by reducing oxidative stress damage via activation of SIRT1 signaling in a receptor-dependent manner.
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Research on the epigenetic modification of pancreatic cancer vaccine.
Hepatogastroenterology
PUBLISHED: 06-06-2014
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Pancreatic cancer is characterized as a type of gastrointestinal tumor with a poor prognosis and high degree of malignancy. CIITA gene was found highly methylated in pancreatic carcinoma cell line PANC-1 and responsible for the low expression of MHC-II that may lead to immune evasion. Here, we tried to prepare pancreatic cancer vaccine with PANC-1 cells via epigenetic modification to enhance the MHC-II expression. Then the vaccine was injected into C57BL/6J mice and the effect was examined. Our study found that the vaccine could promote the proliferation of antigen-specific T cells, enhance the killing activity of cytotoxic lymphocytes (CTL), promote Th1-type cells mediated secretion of cytokines IFN-gamma and IL-2 while inhibiting Th2-type cells mediated secretion of IL-4, and inhibit the secretion of TGF-beta. Generally, the epigenetically modified vaccine could enhance the body's anti-tumor immune response, providing feasibility research on cancer vaccine for therapy of pancreatic cancer.
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Design and analysis of a connected broadband multi-piezoelectric-bimorph- beam energy harvester.
IEEE Trans Ultrason Ferroelectr Freq Control
PUBLISHED: 05-27-2014
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The rapid growth of remote, wireless, and microelectromechanical system (MEMS) devices over the past decades has motivated the development of a self-powered system that can replace traditional electrochemical batteries. Piezoelectric energy harvesters are ideal for capturing energy from mechanical vibrations in the ambient environment. Numerous studies have been made of this application of piezoelectric energy conversion; however, the narrow frequency operation band has limited its application to generate useful power. In this paper, a broadband energy harvester with an array/matrix of piezoelectric bimorphs connected by springs has been designed and analyzed based on the 1-D piezoelectric beam equations. The predicted result shows that the operational frequency band can be enlarged significantly by carefully adjusting the small end masses, length of the beam and spring stiffness. An optimal selection of the load impedance to realize the maximum power output is discussed. The results provide an important foundation for future broadband energy harvester design.
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Upregulation of caveolin-1 contributes to aggravated high-salt diet-induced endothelial dysfunction and hypertension in type 1 diabetic rats.
Life Sci.
PUBLISHED: 05-18-2014
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Endothelial dysfunction and hypertension is more common in individuals with diabetes than in the general population. This study was aimed to investigate the underlying mechanisms responsible for endothelial dysfunction of type 1 diabetic rats fed with high-salt diet.
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Comparative proteomic analyses reveal that the regulators of G-protein signaling proteins regulate amino acid metabolism of the rice blast fungus Magnaporthe oryzae.
Proteomics
PUBLISHED: 04-29-2014
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The rice blast fungus Magnaporthe oryzae encodes eight regulators of G-protein (GTP-binding protein) signaling (RGS) proteins MoRgs1-MoRgs8 that orchestrate the growth, asexual/sexual production, appressorium differentiation, and pathogenicity. To address the mechanisms by which MoRgs proteins function, we conducted a 2DE proteome study and identified 82 differentially expressed proteins by comparing five ?Morgs mutants with wild-type Guy11 strain. We found that the abundances of eight amino acid (AA) biosynthesis or degradation associated proteins were markedly altered in five ?Morgs mutants, indicating one of the main collective roles for the MoRgs proteins is to influence AA metabolism. We showed that MoRgs proteins have distinct roles in AA metabolism and nutrient responses from growth assays. In addition, we characterized MoLys20 (Lys is lysine), a homocitrate synthase, whose abundance was significantly decreased in the ?Morgs mutants. The ?Molys20 mutant is auxotrophic for lys and exogenous lys could partially rescue its auxotrophic defects. Deletion of MoLYS20 resulted in defects in conidiation and infection, as well as pathogenicity on rice. Overall, our results indicate that one of the critical roles for MoRgs proteins is to regulate AA metabolism, and that MoLys20 may be directly or indirectly regulated by MoRgs and participated in lys biosynthesis, thereby affecting fungal development and pathogenicity.
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Threonine deaminase MoIlv1 is important for conidiogenesis and pathogenesis in the rice blast fungus Magnaporthe oryzae.
Fungal Genet. Biol.
PUBLISHED: 04-21-2014
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Threonine deaminase is the first critical enzyme in the biosynthesis of branched-chain amino acids (BCAAs), which catalyzes threonine into NH2 and ketobutyrate acid. Previously, we identified and characterized two acetolactate synthases MoIlv2 and MoIlv6 that are involved in the second step of BCAA biosynthesis. Deletion of MoILV2 and MoILV6 resulted in auxotrophy for leucine, isoleucine, and valine and defects in conidiation, appressorial penetration, and pathogenicity. Here, we identified a threonine dehydratase, named MoIlv1, from M. oryzae. MoIlv1 is a homolog of Saccharomyces cerevisiae Ilv1p, which has an important role in the biosynthesis of isoleucine. To characterize the function of MoIlv1, a ?Moilv1 knock-out mutant was generated and analyzed. Disruption of MoILV1 resulted in abnormal conidial morphology, reduced conidiation, limited appressorium-mediated penetration, and attenuated virulence on both barley and rice seedlings. Further analysis by domain-specific deletion revealed that the PALP domain is indispensable for MoIlv1 function. Our study indicates that MoIlv1 is a protein involved in isoleucine biosynthesis that underlies the complex process governing morphogenesis, appressorium formation, invasive hyphae growth, and pathogenicity.
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Photovoltaic properties of Zr(x)Ti(1-x)O2 solid solution nanowire arrays.
J Nanosci Nanotechnol
PUBLISHED: 04-17-2014
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In this paper, Zr(0.05Ti(0.95)O2 solid solution nanowire arrays (NWs) were prepared by a low temperature hydrothermal method. The as-prepared NWs were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-visible (UV-vis) spectroscopy. With the doping of Zr content, the band gap of the composite can be varied in a wide range and excellent photoelectric properties of the arrays could be obtained. Moreover, a preliminary study on the photoelectric properties was conducted, which indicates potential applications of the arrays for fabricating high performance ultraviolet photodetectors.
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ALY proteins participate in multifaceted Nep1Mo-triggered responses in Nicotiana benthamiana and Arabidopsis thaliana.
J. Exp. Bot.
PUBLISHED: 04-10-2014
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Previously, it was found that Nep1Mo (a Nep1-like protein from Magnaporthe oryzae) could trigger a variety of plant responses, including stomatal closure, hypersensitive cell death (HCD), and defence-related gene expression, in Nicotiana benthamiana. In this study, it was found that Nep1Mo-induced cell death could be inhibited by the virus-induced gene silencing of NbALY916 in N. benthamiana. NbALY916-silenced plants showed impaired Nep1Mo-induced stomatal closure, decreased Nep1Mo-induced production of hydrogen peroxide (H2O2) and nitric oxide (NO) in guard cells, and reduced Nep1Mo-induced resistance against Phytophthora nicotianae. It also found that the deletion of AtALY4, an orthologue of NbALY916 in Arabidopsis thaliana, impaired Nep1Mo-triggered stomatal closure, HCD, and defence-related gene expression. The compromised stomatal closure observed in the NbALY916-silenced plants and AtALY4 mutants was inhibited by the application of H2O2 and sodium nitroprusside (an NO donor), and both Nep1Mo and H2O2 stimulated guard cell NO synthesis. Conversely, NO-induced stomatal closure was found not to require H2O2 synthesis; and NO treatment did not induce H2O2 production in guard cells. Taken together, these results demonstrate that the NbAlY916/AtAlY4-H2O2-NO pathway mediates multiple Nep1Mo-triggered responses, including stomatal closure, HCD, and defence-related gene expression.
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Relationship between brachial-ankle pulse wave velocity and metabolic syndrome components in a Chinese population.
J Biomed Res
PUBLISHED: 03-16-2014
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The purpose of this study was to assess the relationship between arterial stiffness, as measured by brachial-ankle pulse wave velocity (baPWV), and the presence of the metabolic syndrome (MS) in a Chinese population. A total of 4,445 subjects were enrolled. The prevalence of MS in our study population was 21.7%, 17.2% and 25.6% for the general population, males and females, respectively. With adjustments for age, gender, cigarette smoking, heart rate, total cholesterol, low-density lipoprotein (LDL) cholesterol, and the use of anti-hypertensive drug, the stepwise regression analysis showed that baPWV had a significant relationship with components of MS, including systolic blood pressure (P < 0.001), diastolic blood pressure (P < 0.001), glucose (P < 0.001), high-density lipoprotein (HDL) cholesterol (P ?=? 0.04), and triglycerides (P < 0.001), but no relationship with waist circumference (P ?=? 0.25). With an increase in the number of the MS components, baPWV increased significantly both in women and men. This study indicated that the MS is indeed a risk factor for arterial stiffness. Monitoring of baPWV in patients with MS may help in identifying persons at high risk for cardiovascular disease.
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MoLys2 is necessary for growth, conidiogenesis, lysine biosynthesis, and pathogenicity in Magnaporthe oryzae.
Fungal Genet. Biol.
PUBLISHED: 03-16-2014
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Amino acid biosyntheses are complex but essential processes in growth and differentiation of eukaryotic cells. In the budding yeast Saccharomyces cerevisiae, the lysine biosynthesis via the ?-aminoadipate (AA) pathway involves several steps, including reduction of AA to AA 6-semialdehyde by AA reductase ScLys2. In filamentous fungus Penicillium chrysogenum, disruption of the LYS2 gene blocked the lysine biosynthesis but promoted the production of the secondary metabolite penicillin. In comparison, little is known about the function of AA reductase Lys2 in phytopathogenic fungi. We here characterized the functions of MoLys2, a homolog of ScLys2, from the rice blast fungus Magnaporthe oryzae. Our results showed that the ?Molys2 mutants were auxotrophic for lysine. The ?Molys2 mutants also exhibited drastic reduction in pathogenicity on rice, inducing small disease lesions. Microscopic examination of the lesions revealed that the invasive hyphae of ?Molys2 mutants were mostly restricted to the primary infected leaf sheath cells. In addition, exogenous lysine restored the production of conidia and near wild-type appressoria differentiation, and rescued the defect of pathogenicity in conidia infection of detached barely and rice leaf sheath. Our results indicated that MoLys2 is necessary for lysine biosynthesis that affects growth, conidiogenesis, and pathogenicity of the fungus. This study does implicate the potential for targeting lysine biosynthesis for the development of novel fungicides against M. oryzae.
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Characterization of unknown brominated disinfection byproducts during chlorination using ultrahigh resolution mass spectrometry.
Environ. Sci. Technol.
PUBLISHED: 03-07-2014
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Brominated disinfection byproducts (Br-DBPs), formed from the reaction of disinfectant(s) with natural organic matter in the presence of bromide in raw water, are generally more cytotoxic and genotoxic than their chlorinated analogues. To date, only a few Br-DBPs in drinking water have been identified, while a significant portion of Br-DBPs in drinking water is still unknown. In this study, negative ion electrospray ionization ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) was used to characterize unknown Br-DBPs in artificial drinking water. In total, 441 formulas for one-bromine-containing products and 37 formulas for two-bromine-containing products, most of which had not been previously reported, were detected in the chlorinated sample. Most Br-DBPs have corresponding chlorine-containing analogues with identical CHO composition. In addition, on-resonance collision-induced dissociation (CID) of single ultrahigh resolved bromine containing mass peaks was performed in the ICR cell to isolate single bromine-containing components in a very complex natural organic matter spectrum and provide structure information. Relatively abundant neutral loss of CO2 was observed in MS-MS spectra, indicating that the unknown Br-DBPs are rich in carboxyl groups. The results demonstrate that the ESI FT-ICR MS method could provide valuable molecular composition and structure information on unknown Br-DBPs.
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Ultrasonography combined with fluoroscopy for percutaneous nephrolithotomy: an analysis based on seven years single center experiences.
Urol J
PUBLISHED: 03-06-2014
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To assess the efficacy and safety of percutaneous nephrolithotomy (PCNL) under the guidance of ultrasonography and fluoroscopy.
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Discovery of a super-strong promoter enables efficient production of heterologous proteins in cyanobacteria.
Sci Rep
PUBLISHED: 03-03-2014
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Cyanobacteria are oxygenic photosynthetic prokaryotes that play important roles in the global carbon cycle. Recently, engineered cyanobacteria capable of producing various small molecules from CO2 have been developed. However, cyanobacteria are seldom considered as factories for producing proteins, mainly because of the lack of efficient strong promoters. Here, we report the discovery and verification of a super-strong promoter P(cpc560), which contains two predicted promoters and 14 predicted transcription factor binding sites (TFBSs). Using P(cpc560), functional proteins were produced at a level of up to 15% of total soluble protein in the cyanobacterium Synechocystis sp. 6803, a level comparable to that produced in Escherichia coli. We demonstrated that the presence of multiple TFBSs in P(cpc560) is crucial for its promoter strength. Genetically transformable cyanobacteria neither have endotoxins nor form inclusion bodies; therefore, P(cpc560) opens the possibility to use cyanobacteria as alternative hosts for producing heterogeneous proteins from CO2 and inorganic nutrients.
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Sensitivity analysis of multi-layered C-axis inclined zigzag zinc oxide thin-film resonators as viscosity sensors.
IEEE Trans Ultrason Ferroelectr Freq Control
PUBLISHED: 02-27-2014
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This paper presents a theoretical analysis of a new zigzag C-axis inclined multi-layer ZnO thin-film bulk acoustic wave resonator (FBAR) as a viscosity sensor to monitor the lubrication performance of engine oil and other liquids. Free vibration and forced vibration for the FBAR loaded with liquids are analyzed. Equations necessary to calculate the sensitivity are derived. The numerical analysis shows that as the number of layers increases, the absolute sensitivity increases as well. The influences on the sensitivity of C-axis inclined angle, Q-factor, and thickness are also investigated. The results provide a foundation for further design of multi-layer FBAR viscosity sensors.
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Identification and genetic characterization of avian-origin H3N2 canine influenza viruses isolated from the Liaoning province of China in 2012.
Virus Genes
PUBLISHED: 02-26-2014
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A total of 158 serum samples and 510 nasal swab specimens were collected between September 2010 and May 2012, from dogs exhibiting respiratory symptoms, in order to investigate the epidemiology of H3N2 canine influenza viruses (CIVs) in the Liaoning province of China. Serological surveillance demonstrated that 10.8 % (17/158) of serum samples were positive for H3N2 canine influenza. Two H3N2 influenza viruses, A/canine/Liaoning/27/2012 and A/canine/Liaoning/H6/2012, were isolated from pet dogs in 2012. Phylogenetic analysis indicated that the genes from these two viruses were closely related to those of avian-origin, H3N2 subtype CIVs from China and Thailand. Genetic analysis of eight genes revealed that these two H3N2 canine influenza isolates were highly similar (99.2-99.8 %) to the current common strains in Asia. Analysis of the genotype demonstrated that each gene of the two strains in this study had the same genotype (K, G, E, 3B, F, 2D, F, 1E) as those prevalent in H3N2 CIVs. Our findings further confirm that avian-origin H3N2 canine influenza has become established in China. Conducting extensive serological and epidemiological surveillance is necessary to develop an effective vaccine against this disease.
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Mass spectrometry-based metabolomic profiling identifies alterations in salivary redox status and fatty acid metabolism in response to inflammation and oxidative stress in periodontal disease.
Free Radic. Biol. Med.
PUBLISHED: 02-24-2014
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Periodontal diseases represent the most common chronic inflammatory diseases in humans and a major cause of tooth loss. Combining mass spectrometry-based ionomics and targeted lipidomics on fatty acid metabolites, we identified significant alterations in redox status and fatty acid metabolism in saliva in response to chronic inflammation and oxidative stress in periodontal disease in a cohort of nonsmoker subjects with chronic periodontitis. For the first time, ionomic profiling of around 30 ions in saliva revealed significantly decreased levels of redox-active metal ions including Mn, Cu, and Zn in the periodontal group, which is consistent with decreased levels of superoxide dismutases in saliva and serum. A targeted lipidomic approach was employed to monitor the major metabolites of arachidonic acid and linoleic acid in saliva. We observed increased levels of cyclooxygenase products including PGE2, PGD2, and PGF2? and TXB2, but decreased level of PGI2 in the periodontal group. A unique pattern of the lipoxygenase products of arachidonic acid and linoleic acid was observed with increased level of 5-HETE but decreased levels of 13-HODE and 9-HODE. Levels of salivary F2-isoprostanes, free radical lipid peroxidation products, and a gold standard for oxidative stress in vivo were also significantly elevated. Taking these data together, our study using multiple powerful omics techniques demonstrates that local redox alteration contributes significantly to periodontitis through the modulation of fatty acid metabolism in response to inflammation and oxidative stress. This study highlights the importance of redox status in periodontitis and provides a rationale for preventing periodontal disease by dietary interventions aiming to restore redox balance.
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Beneficial effects of thymosin ?4 on spinal cord injury in the rat.
Neuropharmacology
PUBLISHED: 02-08-2014
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Thymosin ?4 (T?4) has many physiological functions that are highly relevant to spinal cord injury (SCI), including neuronal survival, anti-inflammation, wound repair promotion, and angiogenesis. The present study investigated the therapeutic value of T?4 in SCI, with a focus on its neuroprotective, anti-inflammatory, and vasculoprotective properties. T?4 or a saline control was administered by intraperitoneal injection 30 min, 3 days, or 5 days after SCI with mild compression in rat. Locomotor recovery was tested with the Basso-Beattie-Bresnahan scale and a footprint analysis. All behavioral assessments were markedly improved with T?4 treatment. Histological examination at 7 days post injury showed that the numbers of surviving neurons and oligodendrocytes were significantly increased in T?4-treated animals compared to saline-treated controls. Levels of myelin basic protein, a marker of mature oligodendrocytes, in T?4-treated rats were 57.8% greater than those in saline-treated controls. The expression of ED1, a marker of activated microglia/macrophages, was reduced by 36.9% in the T?4-treated group compared to that of the saline-treated group. T?4 treatment after SCI was also associated with a significant decrease in pro-inflammatory cytokine gene expression and a significant increase in the mRNA levels of IL-10 compared to the control. Moreover, the size of lesion cavity delineated by astrocyte scar in the injured spinal cord was markedly reduced in T?4-treated animals compared to saline-treated controls. Given the known safety of T?4 in clinical trials and its beneficial effects on SCI recovery, the results of this study suggested that T?4 is a good candidate for SCI treatment in humans.
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Renal access by sonographer versus urologist during percutaneous nephrolithotomy.
Urol J
PUBLISHED: 01-29-2014
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To evaluate the percutaneous access outcomes and complications following percutaneous nephrolithotomy (PCNL) that was obtained by sonographer or urologist at a single academic institution.
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Semen cassiae attenuates myocardial ischemia and reperfusion injury in high-fat diet streptozotocin-induced type 2 diabetic rats.
Am. J. Chin. Med.
PUBLISHED: 01-29-2014
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Obese patients with type 2 diabetes mellitus (T2DM), which is characterized by hyperglycemia, are liable to more severe myocardial infarction. Semen Cassiae is proven to reduce serum lipid levels. This study investigated whether the Semen Cassiae extract (SCE) reduces myocardial ischemia and reperfusion (MI/R) injury with or without diabetes and the underlying mechanisms. The high-fat diet-fed streptozotocin (HFD-STZ) rat model was created as a T2DM model. Normal and DM rats received SCE treatment orally (10 mg/kg/day) for one week. Subsequently these animals were subjected to MI/R. Compared with the normal animals, DM rats showed increased plasma total cholesterol (TC) and triacylglycerol (TG), and more severe MI/R injury and cardiac functional impairment. SCE treatment significantly reduced the plasma TC and TG, improved the instantaneous first derivation of left ventricle pressure and reduced infarct size, decreased plasma creatine kinase and lactate dehydrogenase levels, and apoptosis index at the end of reperfusion in diabetic rats. Moreover, SCE treatment increased the antiapoptotic protein Akt and ERK1/2 phosphorylation levels. Pretreatment with a PI3K inhibitor wortmannin or an ERK1/2 inhibitor PD98059 not only blocked Akt and ERK1/2 phosphorylation respectively, but also inhibited the cardioprotective effects of SCE. However, SCE treatment did not show any effects on the MI/R injury in the normal rats. Our data suggest that SCE effectively improves myocardial function and reduces MI/R-induced injury in diabetic but not normal animals, which is possibly attributed to the reduced TC/TG levels and the triggered cell survival signaling Akt and ERK1/2.
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An Integrated Epidemiological and Economic Analysis of Vaccination against Highly Pathogenic Porcine Reproductive and Respiratory Syndrome (PRRS) in Thua Thien Hue Province, Vietnam.
Asian-australas. J. Anim. Sci.
PUBLISHED: 01-23-2014
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The purposes of this study are to assess pig farmers' preference for highly pathogenic porcine reproductive and respiratory syndrome (PRRS) vaccine, and estimate the cost and benefit of PRRS vaccination in Vietnam. This study employed an integrated epidemiological and economic analysis which combined susceptible-infectious-recovered (SIR) model, choice experiment (CE) and cost-benefit analysis (CBA) together. The result of SIR model showed the basic reproduction number (R0) of PRRS transmission in this study is 1.3, consequently, the optimal vaccination percentage is 26%. The results of CE in this study indicate that Vietnam pig farmers are showing a high preference for the PRRS vaccine. However, their mean willingness to pay is lower than the potential cost of PRRS vaccine. It can be considered to be one of the reasons that the PRRS vaccination ratio is still low in Vietnam. The results of CBA specified from the whole society's point of view (Social perspective), the benefits of PRRS vaccination are 2.3 to 4.5 times larger than the costs. To support policy making for increasing the PRRS vaccination proportion, this study indicates two ways to increase the vaccination proportion: i) decrease vaccine price by providing a subsidy, ii) provide compensation of culling only for PRRS vaccinated pigs.
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Performance enhancement and fouling mitigation by organic flocculant addition in membrane bioreactor at high salt shock.
Bioresour. Technol.
PUBLISHED: 01-22-2014
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The main objective of this study was to investigate the effect of an organic flocculant (MPE50) addition on reducing membrane fouling and enhancing performance in membrane bioreactor (MBR) at the high salt shock. Results show that MPE50 addition is a reliable and effective approach in terms of both membrane fouling mitigation and pollutants removal improvement in the case of high salt shock. Compared to the control reactor, the MBR with MPE50 addition enhanced the average removal of COD, NH4(+)-N and TP by 4.1%, 13.2% and 21.2%, respectively. Due to the effect of flocculation and adsorption by MPE50, a significant reduction in the soluble microbial products (SMP) proteins amount was observed. As a result, the membrane fouling rate was mitigated successfully. Further, the increasing of mean particles size, Zeta potential and related hydrophobicity of the flocs would also have positive impacts on membrane fouling mitigation.
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Pleiotropic function of the putative zinc-finger protein MoMsn2 in Magnaporthe oryzae.
Mol. Plant Microbe Interact.
PUBLISHED: 01-11-2014
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The mitogen-activated protein kinase MoOsm1-mediated osmoregulation pathway plays crucial roles in stress responses, asexual and sexual development, and pathogenicity in Magnaporthe oryzae. Utilizing an affinity purification approach, we identified the putative transcriptional activator MoMsn2 as a protein that interacts with MoOsm1 in vivo. Disruption of the MoMSN2 gene resulted in defects in aerial hyphal growth, conidial production, and infection of host plants. Quantitative reverse transcription-polymerase chain reaction analysis showed that the expression of several genes involved in conidiophore formation was reduced in ?Momsn2, suggesting that MoMsn2 might function as a transcriptional regulator of these genes. Subsequently, MoCos1 was identified as one of the MoMsn2 targets through yeast one-hybrid analysis in which MoMsn2 binds to the AGGGG and CCCCT motif of the MoCOS1 promoter region. Phenotypic characterization showed that MoMsn2 was required for appressorium formation and penetration and pathogenicity. Although the ?Momsn2 mutant was tolerant to the cell-wall stressor Calcofluor white, it was sensitive to common osmotic stressors. Further analysis suggests that MoMsn2 is involved in the regulation of the cell-wall biosynthesis pathway. Finally, transcriptome data revealed that MoMsn2 modulates numerous genes participating in conidiation, infection, cell-wall integrity, and stress response. Collectively, our results led to a model in which MoMsn2 mediates a series of downstream genes that control aerial hyphal growth, conidiogenesis, appressorium formation, cell-wall biosynthesis, and infection and that also offer potential targets for the development of new disease management strategies.
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AIP1 mediates vascular endothelial cell growth factor receptor-3-dependent angiogenic and lymphangiogenic responses.
Arterioscler. Thromb. Vasc. Biol.
PUBLISHED: 01-09-2014
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To investigate the novel function of ASK1-interacting protein-1 (AIP1) in vascular endothelial cell growth factor receptor (VEGFR)-3 signaling, and VEGFR-3-dependent angiogenesis and lymphangiogenesis.
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Synthesis of superparamagnetic iron oxide nanoparticles coated with a DDNP-carboxyl derivative for in vitro magnetic resonance imaging of Alzheimer's disease.
Mater Sci Eng C Mater Biol Appl
PUBLISHED: 01-05-2014
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Superparamagnetic iron oxide nanoparticles (SPIONs) have been proposed for use in magnetic resonance imaging as versatile ultra-sensitive nanoprobes for Alzheimer's disease imaging. In this work, we synthetized an efficient contrast agent of Alzheimer's disease using 1,1-dicyano-2-[6-(dimethylamino)naphthalene-2-yl]propene (DDNP) carboxyl derivative to functionalize the surface of SPIONs. The DDNP-SPIONs are prepared by conjugating DDNP carboxyl derivative to oleic acid-treated SPIONs through ligand exchange. The structure, size distribution and magnetic property were identified by IR, TGA-DTA, XRD, TEM, Zetasizer Nano and VSM. TEM and Zetasizer Nano observations indicated that the DDNP-SPIONs are relatively mono-dispersed spherical distribution with an average size of 11.7nm. The DDNP-SPIONs were then further analyzed for their MRI relaxation properties using MR imaging and demonstrated high T2 relaxivity of 140.57s(-1)FemM(-1), and the vitro experiment that DDNP-SPIONs binding to ?-Amyloid aggregates were then investigated by fluorophotometry, the results showed that the combination had induced the fluorescence enhancement of the DDNP-SPIONs and displayed tremendous promise for use as a contrast agent of Alzheimer's disease in MRI.
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Robustness of controllability for networks based on edge-attack.
PLoS ONE
PUBLISHED: 01-01-2014
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We study the controllability of networks in the process of cascading failures under two different attacking strategies, random and intentional attack, respectively. For the highest-load edge attack, it is found that the controllability of Erd?s-Rényi network, that with moderate average degree, is less robust, whereas the Scale-free network with moderate power-law exponent shows strong robustness of controllability under the same attack strategy. The vulnerability of controllability under random and intentional attacks behave differently with the increasing of removal fraction, especially, we find that the robustness of control has important role in cascades for large removal fraction. The simulation results show that for Scale-free networks with various power-law exponents, the network has larger scale of cascades do not mean that there will be more increments of driver nodes. Meanwhile, the number of driver nodes in cascading failures is also related to the edges amount in strongly connected components.
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Alpha-linolenic acid intake prevents endothelial dysfunction in high-fat diet-fed streptozotocin rats and underlying mechanisms.
VASA
PUBLISHED: 11-14-2013
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Endothelial dysfunction is an important factor in the pathogenesis of diabetes related vascular complications, and acute alpha-linolenic acid (ALA) intake can increase flow-mediated dilation of the diabetic artery at 4 h postprandially. However, whether chronic ALA supplementation may prevent endothelial dysfunction in the process of diabetes and underlying mechanisms remains largely unknown.
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Reduced high-molecular-weight adiponectin is an independent risk factor for cardiovascular lesions in hypercholesterolaemic patients.
Clin. Endocrinol. (Oxf)
PUBLISHED: 09-13-2013
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The hormone adiponectin (APN) circulates in plasma as various multimeric complexes. The high-molecular-weight (HMW) isoform has been reported to exert the most favourable metabolic regulatory and vasculoprotective effects. This study determined the circulatory distribution of APN multimers and their relationships with cardiovascular disease (CVD)-related biochemical indicators in patients with hypercholesterolaemia (HC).
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[Sodium hydrosulfide for prevention of kidney damage in rats after amputation].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 09-03-2013
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To explore the mechanism of kidney injury in rats following amputation and the protective effects of sodium hydrosulfide (NaHS) on kidney structure and function.
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Achyranthes bidentata polypeptides reduces oxidative stress and exerts protective effects against myocardial ischemic/reperfusion injury in rats.
Int J Mol Sci
PUBLISHED: 08-19-2013
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Achyranthes bidentata, a Chinese medicinal herb, is reported to be neuroprotective. However, its role in cardioprotection remains largely unknown. Our present study aimed to investigate the effects of Achyranthes bidentata polypeptides (ABPP) preconditioning on myocardial ischemia/reperfusion (MI/R) injury and to test the possible mechanisms. Rats were treated with ABPP (10 mg/kg/d, i.p.) or saline once daily for one week. Afterward, all the animals were subjected to 30 min of myocardial ischemia followed by 4 h of reperfusion. ABPP preconditioning for one week significantly improved cardiac function following MI/R. Meanwhile, ABPP reduced infarct size, plasma creatine kinase (CK)/lactate dehydrogenase (LDH) activities and myocardial apoptosis at the end of reperfusion in rat hearts. Moreover, ABPP preconditioning significantly inhibited superoxide generation, gp91phox expression, malonaldialdehyde formation and enhanced superoxide dismutase activity in I/R hearts. Furthermore, ABPP treatment inhibited PTEN expression and increased Akt phosphorylation in I/R rat heart. PI3K inhibitor wortmannin blocked Akt activation, and abolished ABPP-stimulated anti-oxidant effect and cardioprotection. Our study demonstrated for the first time that ABPP reduces oxidative stress and exerts cardioprotection against MI/R injury in rats. Inhibition of PTEN and activation of Akt may contribute to the anti-oxidant capacity and cardioprotection of ABPP.
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Characterization of a novel humanized anti-CD20 antibody with potent anti-tumor activity against non-Hodgkins lymphoma.
Cell. Physiol. Biochem.
PUBLISHED: 08-18-2013
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Rituximab, a mouse Fab and human Fc chimeric antibody, has been widely used to treat Non-Hodgkins lymphoma (NHL). However, only 48% of patients respond to the treatment and complete response rate is below 10%. Also, immunogenicity was reported in 17-20% patients receiving the treatment, making it unsuitable for long term diseases such as autoimmune disorders. It has been a hot research field to "humanize" rituximab toward improved efficacy and reduced immunogenicity.
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Measurements of Youngs and shear moduli of rail steel at elevated temperatures.
Ultrasonics
PUBLISHED: 08-10-2013
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The design and modelling of the buckling effect of Continuous Welded Rail (CWR) requires accurate material constants, especially at elevated temperatures. However, such material constants have rarely been found in literature. In this article, the Youngs moduli and shear moduli of rail steel at elevated temperatures are determined by a new sonic resonance method developed in our group. A network analyser is used to excite a sample hanged inside a furnace through a simple tweeter type speaker. The vibration signal is picked up by a Polytec OFV-5000 Laser Vibrometer and then transferred back to the network analyser. Resonance frequencies in both the flexural and torsional modes are measured, and the Youngs moduli and shear moduli are determined through the measured resonant frequencies. To validate the measured elastic constants, the measurements have been repeated by using the classic sonic resonance method. The comparisons of obtained moduli from the two methods show an excellent consistency of the results. In addition, the material elastic constants measured are validated by an ultrasound test based on a pulse-echo method and compared with previous published results at room temperature. The measured material data provides an invaluable reference for the design of CWR to avoid detrimental buckling failure.
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Improvement of vascular insulin sensitivity by downregulation of GRK2 mediates exercise-induced alleviation of hypertension in spontaneously hypertensive rats.
Am. J. Physiol. Heart Circ. Physiol.
PUBLISHED: 08-02-2013
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Exercise training lowers blood pressure and is a recommended nonpharmacological strategy and useful adjunctive therapy for hypertensive patients. Studies demonstrate that physical activity attenuates progression of hypertension. However, underlying mechanisms remain elusive. Vascular insulin resistance and endothelial dysfunction plays a critical role in the development of hypertension. The present study investigated whether long-term physical exercise starting during the prehypertensive period prevents the development of hypertension via improving vascular insulin sensitivity. Young (4 wk old) prehypertensive spontaneously hypertensive rats (SHRs) and their normotensive Wistar-Kyoto (WKY) control rats were subjected to a 10-wk free-of-loading swim training session (60 min/day, 5 days/wk). Blood pressure, mesenteric arteriolar vasorelaxation, G protein-coupled receptor kinase-2 (GRK2) expression and activity, and insulin-stimulated Akt/endothelial nitric oxide synthase (eNOS) activation were determined. SHRs had higher systolic blood pressure, systemic insulin resistance, and impaired vasodilator actions of insulin in resistance vessels when compared with WKY rats. Systolic blood pressure in SHRs postexercise was significantly lower than that in sedentary rats. Vascular insulin sensitivity in mesenteric arteries was improved after exercise training as evidenced by an increased vasodilator response to insulin. In addition, exercise downregulated vascular GRK2 expression and activity, which further increased insulin-stimulated vascular Akt/eNOS activation in exercised SHRs. Specific small interfering RNA knockdown of GRK2 in endothelium mimicked the effect of exercise-enhanced vascular insulin sensitivity. Likewise, upregulation of GRK2 by Chariot-mediated delivery opposed exercise-induced vascular insulin sensitization. Taken together, our results suggest that long-term exercise beginning at the prehypertensive stage improves vascular insulin sensitivity via downregulation of vascular GRK2 that may help to limit the progression of hypertension.
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Downregulation of hepatic stimulator substance during the early phase of liver regeneration inhibits E-cadherin expression in mice.
Int. J. Biochem. Cell Biol.
PUBLISHED: 07-31-2013
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Hepatic stimulatory substance (HSS), which encodes a sulfhydryl oxidase enzyme, promotes liver regeneration (LR) and maintains the viability of hepatocytes. Surprisingly, we found that the levels of the HSS mRNA and expressed protein were both strongly repressed at 12h after a 70% partial hepatectomy (PH) in mice. Understanding the mechanism and effect of this extraordinary suppression can provide a novel path for exploring the molecular function of HSS during LR. We observed that the EGF levels in the serum were negatively correlated with HSS expression in regenerating livers. Treating primary mouse hepatocytes or Hepa1-6 cells with EGF suppressed HSS mRNA expression. This suppression was transcriptional and was mediated by the effect of EGF on the phosphorylation of CCAAT/enhancer-binding protein ? (C/EBP?), which regulates HSS expression. We further showed that the enhanced phosphorylation of C/EBP? after PH promoted its interaction with the HSS promoter and repressed HSS expression at early time-points after PH. Interestingly, the knockdown of HSS caused a dramatic decrease in E-cadherin expression in hepatocytes. E-cadherin expression was also significantly suppressed at 12h after PH. Moreover, the pre-injection of HSS-expressing adenovirus vectors prevented E-cadherin suppression after PH. Treatment with C/EBP? siRNA reversed the EGF-mediated inhibition of HSS expression and led to enhanced E-cadherin expression and reduced cell migration. Our findings suggest that C/EBP? directly inhibits the HSS promoter after PH and that this inhibition can downregulate E-cadherin expression. These data provide novel insight into the potential role of HSS in hepatic structural reconstruction during LR.
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Acetolactate synthases MoIlv2 and MoIlv6 are required for infection-related morphogenesis in Magnaporthe oryzae.
Mol. Plant Pathol.
PUBLISHED: 06-19-2013
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Amino acids are important components in the metabolism of a variety of pathogens, plants and animals. Acetolactate synthase (ALS) catalyses the first common step in leucine, isoleucine and valine biosynthesis, and is the target of several classes of inhibitors. Here, MoIlv2, an orthologue of the Saccharomyces cerevisiae?ALS catalytic subunit Ilv2, and MoIlv6, an orthologue of the S.?cerevisiae?ALS regulatory subunit Ilv6, were identified. To characterize MoILV2 and MoILV6 functions, we generated the deletion mutants ?Moilv2 and ?Moilv6. Phenotypic analysis showed that both mutants were auxotrophic for leucine, isoleucine and valine, and were defective in conidial morphogenesis, appressorial penetration and pathogenicity. Further studies suggested that MoIlv2 and MoIlv6 play a critical role in maintaining the balance of intracellular amino acid levels. MoIlv2 and MoIlv6 are both localized to the mitochondria and the signal peptide of MoIlv6 is critical for its localization. In summary, our evidence indicates that MoIlv2 plays a crucial role in isoleucine and valine biosynthesis, whereas MoIlv6 contributes to isoleucine and leucine biosynthesis; both genes are required for fungal pathogenicity. This study indicates the potential of targeting branched-chain amino acid biosynthesis for anti-rice blast management.
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Influences of surface capping with electrostatically self-assembled PEI on the photoresponse of a TiO2 thin film.
Chem. Commun. (Camb.)
PUBLISHED: 06-08-2013
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The photoresponse of a TiO2 thin film was significantly improved due to the decrease in the Schottky barrier height between Au and TiO2 via the formation of interface dipoles, which was caused by electrostatically self-assembled PEI on the surface of the TiO2 film.
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Occurrence, profiling and prioritization of halogenated disinfection by-products in drinking water of China.
Environ Sci Process Impacts
PUBLISHED: 06-08-2013
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The occurrence of 28 disinfection by-products (DBPs), which were divided into 5 groups, in 70 drinking water treatment plants in 31 cities across China was investigated, and the toxic potency of each DBP group was calculated using mammalian cell toxicity data from previous studies for profiling. Of the 28 DBPs, 21 were detected with an average frequency of detection of 50%. Trihalomethanes (THM4) and haloacetic acids (HAAs) were the most predominant species, whose median concentration levels were at 10.53 and 10.95 ?g L(-1), respectively. Two of four iodinated trihalomethanes (I-THMs) were detected, and the concentration of the I-THMs ranged from under the detection limit to 5.58 ?g L(-1). The total concentration of haloacetonitriles (HANs) in different water samples ranged from under the limit of detection to 39.20 ?g L(-1), with a median concentration of 1.11 ?g L(-1). Two of four halonitromethanes (HNMs) were detected, and the maximum concentrations of chloronitromethane (CNM) and trichloronitromethane (TCNM) were 0.96 and 0.28 ?g L(-1), respectively. HANs were found to be the most potent DBP group in terms of cytotoxicity, and HANs and HAAs had the same level of genotoxic potency. These results indicate that although at a low concentration level, the toxic potency of the unregulated HANs in drinking water may not be neglected.
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Apparatus for measurement of acoustic wave propagation under uniaxial loading with application to measurement of third-order elastic constants of piezoelectric single crystals.
Rev Sci Instrum
PUBLISHED: 06-08-2013
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We describe an apparatus for the measurement of acoustic wave propagation under uniaxial loading featuring a special mechanism designed to assure a uniform mechanical load on a cube-shaped sample of piezoelectric material. We demonstrate the utility of the apparatus by determining the effects of stresses on acoustic wave speed, which forms a foundation for the final determination of the third-order elastic constants of langasite and langatate single crystals. The transit time method is used to determine changes in acoustic wave velocity as the loading is varied. In order to minimize error and improve the accuracy of the wave speed measurements, the cross correlation method is used to determine the small changes in the time of flight. Typical experimental results are presented and discussed.
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Serum oxidant and antioxidant status following an all-out 21-km run in adolescent runners undergoing professional training--a one-year prospective trial.
Int J Mol Sci
PUBLISHED: 06-06-2013
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This study investigated the 1-year longitudinal effect of professional training in adolescent runners on redox balance during intense endurance exercise. Changes in selected serum oxidant and antioxidant status in response to a 21-km running time trial in 10 runners (15.5 ± 1.3 years) undergoing professional training were evaluated twice in 12 months (pre- and post-evaluation). Venous blood samples were collected immediately before and 4-h following the 21-km run for analysis of serum concentrations of thiobarbituric acid-reactive substances (TBARS), xanthine oxidase (XO), catalase (CAT), reduced glutathione (GSH), superoxide dismutase (SOD), and total antioxidant capacity (T-AOC). In pre-evaluation trial, serum TBARS and SOD decreased after the 21-km run (p < 0.05) while XO, GSH, CAT and TAOC were unchanged. In post-evaluation trial, serum TBARS and SOD decreased, whereas XO and CAT increased post-exercise (p < 0.05). Furthermore, pre-exercise serum T-AOC, post-exercise serum XO, CAT, T-AOC (p < 0.05), and GSH (p = 0.057) appeared to be higher than the corresponding pre-evaluation values. The current findings suggest that a professional training regime in adolescent runners is not likely to jeopardize the development of their antioxidant defense. However, uncertainties in the maintenance of redox balance in runners facing increased exercise-induced oxidative stress as a consequence of training-induced enhancement of exercise capacity await further elucidation.
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The imprinted H19 lncRNA antagonizes let-7 microRNAs.
Mol. Cell
PUBLISHED: 05-22-2013
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Abundantly expressed in fetal tissues and adult muscle, the developmentally regulated H19 long noncoding RNA (lncRNA) has been implicated in human genetic disorders and cancer. However, how H19 acts to regulate gene function has remained enigmatic, despite the recent implication of its encoded miR-675 in limiting placental growth. We noted that vertebrate H19 harbors both canonical and noncanonical binding sites for the let-7 family of microRNAs, which plays important roles in development, cancer, and metabolism. Using H19 knockdown and overexpression, combined with in vivo crosslinking and genome-wide transcriptome analysis, we demonstrate that H19 modulates let-7 availability by acting as a molecular sponge. The physiological significance of this interaction is highlighted in cultures in which H19 depletion causes precocious muscle differentiation, a phenotype recapitulated by let-7 overexpression. Our results reveal an unexpected mode of action of H19 and identify this lncRNA as an important regulator of the major let-7 family of microRNAs.
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Quantitative assessment of the association between MHTFR C677T (rs1801133, Ala222Val) polymorphism and susceptibility to bladder cancer.
Diagn Pathol
PUBLISHED: 05-15-2013
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The association between Methylenetetrahydrofolate reductase (MTHFR) Ala222Val (rs1801133) has been implicated to alter the risk of bladder cancer, but the results are controversial.
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Analysis of contributions of nonlinear material constants to stress-induced velocity shifts of quartz and langasite surface acoustic wave resonators.
IEEE Trans Ultrason Ferroelectr Freq Control
PUBLISHED: 05-11-2013
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Stress-induced surface acoustic wave velocity shifts are analyzed for langasite (LGS) SAW resonators. The analytical methodology has been verified by comparing experimental results and analytical results for quartz resonators. LGS SAW resonators with Euler angles which are most sensitive and least sensitive to diametrical forces are determined and their applications in force sensors and resonators with minimum acceleration sensitivity are discussed. Sensitivity of the analytical results to different groups of nonlinear material constants is discussed; it was found that for specific configurations, failure to include the third-order piezoelectric constants, dielectric constants and electrostrictive constants may lead to a significant calculation error. Surface acoustic waves propagating on an LGS square plate subject to bending moment along the propagation direction and normal to the propagation direction are analyzed; it was found that the average momentinduced velocity shift of LGS resonators are comparable to quartz resonators. Analyses of the sensitivity of the results to different groups of nonlinear material constants shows that for some specific wave propagation directions, failure to include the third-order piezoelectric constants, dielectric constants, and electrostrictive constants may lead to large errors.
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Experimental measurement of the electroelastic effect in thickness-mode langasite resonators.
IEEE Trans Ultrason Ferroelectr Freq Control
PUBLISHED: 05-11-2013
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The electroelastic effect describes the shift in resonant frequency that a resonator experiences as a result of the application of a dc electrical field. We report on experimental measurements of the electroelastic effect observed in fourteen plano-plano configuration thickness-mode langasite (La3Ga5SiO14) resonators. The orientations of the fourteen samples provide a sufficient data set to extract all eight of the third-order piezoelectric constants of this material. The role of this type of measurement in determining third-order piezoelectric constants is discussed. We compare the experimentally observed behavior to that predicted when using the langasite material constants currently available in the literature.
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Drive-level dependence of doubly rotated langasite resonators with different configurations.
IEEE Trans Ultrason Ferroelectr Freq Control
PUBLISHED: 05-11-2013
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The miniaturization of crystal resonators and filters toward the micro electromechanical systems (MEMS) and nano-structured scales demands improvement of nonlinear piezoelectricity theory and a better understanding of the nonlinear behavior of new crystal materials. The nonlinearities affect the quality factor and acoustic behavior of MEMS and nano-structured resonators and filters. Among these nonlinear effects, drive-level dependence (DLD), which describes the instability of the resonator frequency resulting from voltage level and/or power density, is a potentially significant problem for miniaturized resonators. Langasite, a promising new piezoelectric material, is of current interest for a variety of applications because of its good temperature behavior, good piezoelectric coupling, low acoustic loss, and high Q-factor. It has been recently used to make high-temperature MEMS. In this paper, we report experimental measurements of the DLD of langasite resonators with different resonator configurations (plano-plano, single bevel, and double bevel). The results show that the resonator configuration affects the DLD of the langasite resonator. The DLD measurement results for langasite are compared with literature values for quartz, langaniste, and langatate, and with additional new measurements for a GaPO4 resonator of type R-30 (-11.1° rotated Y-cut). Uncertainty analysis for the measured drive-level sensitivity is performed as well.
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A network of interactions enables CCM3 and STK24 to coordinate UNC13D-driven vesicle exocytosis in neutrophils.
Dev. Cell
PUBLISHED: 05-06-2013
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Neutrophil degranulation plays an important role in acute innate immune responses and is tightly regulated because the granule contents can cause tissue damage. However, this regulation remains poorly understood. Here, we identify the complex of STK24 and CCM3 as being an important regulator of neutrophil degranulation. Lack of either STK24 or CCM3 increases the release of a specific granule pool without affecting other neutrophil functions. STK24 appears to suppress exocytosis by interacting and competing with UNC13D C2B domain for lipid binding, whereas CCM3 has dual roles in exocytosis regulation. Although CCM3 stabilizes STK24, it counteracts STK24-mediated inhibition of exocytosis by recruiting STK24 away from the C2B domain through its Ca(2+)-sensitive interaction with UNC13D C2A domain. This STK24/CCM3-regulated exocytosis plays an important role in the protection of kidneys from ischemia-reperfusion injury. Together, these findings reveal a function of the STK24 and CCM3 complex in the regulation of ligand-stimulated exocytosis.
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[Effect of compound whole grain-soybean on oxidative stress].
Wei Sheng Yan Jiu
PUBLISHED: 04-20-2013
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To observe the in vitro oxidation resistance of compound whole grain and the effect on improving the disorder of lipid metabolism and the oxidative stress in rats.
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SOCS1 Prevents Graft Arteriosclerosis by Preserving Endothelial Cell Function.
J. Am. Coll. Cardiol.
PUBLISHED: 04-11-2013
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The aim of this study was to determine the role of Suppressor of Cytokine Signaling 1 (SOCS1) in graft arteriosclerosis (GA).
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Role of glycogen synthase kinase 3? in protective effect of propofol against hepatic ischemia-reperfusion injury.
J. Surg. Res.
PUBLISHED: 04-11-2013
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It was previously reported that propofol, an intravenously administered hypnotic and anesthetic agent, protects organs from ischemia-reperfusion (I/R) injury. However, the underlying mechanisms are largely unknown. Glycogen synthase kinase 3? (GSK-3?) is known to play an important role in the oxidative stress-induced apoptosis. In this study, we investigated the role of GSK-3? and mitochondrial permeability transition pore (MPTP) in the protective effects of propofol against hepatic I/R injury.
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Tamoxifen inhibits migration of estrogen receptor-negative hepatocellular carcinoma cells by blocking the swelling-activated chloride current.
J. Cell. Physiol.
PUBLISHED: 04-04-2013
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Tamoxifen is a triphenylethylene non-steroidal antiestrogen anticancer agent. It also shows inhibitory effects on metastasis of estrogen receptor (EsR)-independent tumors, but the underlying mechanism is unclear. It was demonstrated in this study that, in EsR-negative and highly metastatic human hepatocellular carcinoma MHCC97H cells, tamoxifen-inhibited cell migration, volume-activated Cl(-) currents (I(Cl,vol)) and regulatory volume decrease (RVD) in a concentration-dependent manner with a similar IC(50). Analysis of the relationships between migration, I(Cl,vol) and RVD showed that cell migration was positively correlated with I(Cl,vol) and RVD. Knockdown of the expression of ClC-3 Cl(-) channel proteins by ClC-3 shRNA or siRNA inhibited I(Cl,vol), and cell migration, and these inhibitory effects could not be increased further by addition of tamoxifen in the medium. The results suggest that knockdown of ClC-3 expression may deplete the effects of tamoxifen; tamoxifen may inhibit cell migration by modulating I(Cl,vol) and cell volume. Moreover, tamoxifen decreased the activity of protein kinase C (PKC) and the effects were reversed by the PKC activator PMA. Activation of PKC by PMA could competitively downregulate the inhibitory effects of tamoxifen on I(Cl,vol). PMA promoted cell migration, and knockdown of ClC-3 expression by ClC-3 siRNA abolished the PMA effect on cell migration. The results suggest that tamoxifen may inhibit I(Cl,vol) by suppressing PKC activation; I(Cl,vol) may be an EsR-independent target for tamoxifen in the anti-metastatic action on cancers, especially on EsR-negative cancers. The finding may have an implication in the clinical use of tamoxifen in the treatments of both EsR-positive and EsR-negative cancers.
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Insulin alleviates posttrauma cardiac dysfunction by inhibiting tumor necrosis factor-?-mediated reactive oxygen species production.
Crit. Care Med.
PUBLISHED: 03-27-2013
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Clinical evidence indicates that intensive insulin treatment prevents the incidence of multiple organ failures in surgical operation and severe trauma, but the mechanisms involved remain elusive. This study was designed to test the hypothesis that insulin may exert anti-inflammatory and antioxidative effects and thus alleviate cardiac dysfunction after trauma.
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Functional analyses of TNFR2 in physiological and pathological retina angiogenesis.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 03-13-2013
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To determine the function of tumor necrosis factor receptor-2 (TNFR2) in retinal development and ischemia-induced revascularization in an oxygen-induced retinopathy (OIR) model.
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A novel mechanism for vascular insulin resistance in normotensive young SHRs: hypoadiponectinemia and resultant APPL1 downregulation.
Hypertension
PUBLISHED: 03-11-2013
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Vascular insulin resistance contributes to elevated peripheral vascular resistance and subsequent hypertension. Clinical observation showed that lower plasma adiponectin concentration is significantly associated with hypertension. This study was aimed to determine whether hypoadiponectinemia induces vascular insulin resistance before systemic hypertension and the underlying mechanisms. Four-week-old young spontaneously hypertensive rats (ySHRs, normotensive) and adiponectin knockout (KO; APN(-/-)) mice were used to evaluate the role of hypoadiponectinemia in insulin-induced vasodilation of resistance vessels. ySHRs showed significant vascular insulin resistance as evidenced by the blunted vasorelaxation response to insulin in mesenteric arterioles compared with that of age-matched Wistar-Kyoto controls. Serum adiponectin and mesenteric arteriolar APPL1 (an adaptor protein that mediates adiponectin signaling) expression of ySHRs were significantly reduced. In addition, Akt and endothelial NO synthase phosphorylation and NO production in arterioles were markedly reduced, whereas extracellular signal-regulated protein kinases 1/2 (ERK1/2) phosphorylation and endothelin-1 secretion were augmented in ySHRs. APN(-/-) mice showed significantly decreased APPL1 expression and vasodilation evoked by insulin. More importantly, treatment of ySHRs in vivo with the globular domain of adiponectin for 1 week increased APPL1 expression and insulin-induced vasodilation, and restored the balance between insulin-stimulated endothelial vasodilator NO and vasoconstrictor endothelin-1. In cultured human umbilical vein endothelial cells, globular domain of adiponectin upregulated APPL1 expression. Suppression of APPL1 expression with small interfering RNA markedly blunted the globular domain of adiponectin-induced insulin sensitization as evidenced by reduced Akt/endothelial NO synthase and potentiated ERK1/2 phosphorylations. In conclusion, hypoadiponectinemia induces APPL1 downregulation in the resistance vessels, contributing to the development of vascular insulin resistance by differentially modulating the Akt/endothelial NO synthase/NO and ERK1/2/endothelin-1 pathways in vascular endothelium in normotensive ySHRs.
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The ClC-3 chloride channel associated with microtubules is a target of paclitaxel in its induced-apoptosis.
Sci Rep
PUBLISHED: 03-08-2013
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Recent evidences show that cationic fluxes play a pivotal role in cell apoptosis. In this study, the roles of Cl(-) channels in paclitaxel-induced apoptosis were investigated in nasopharyngeal carcinoma CNE-2Z cells. Chloride current and apoptosis were induced by paclitaxel and inhibited by chloride channel blockers. Paclitaxel-activated current possessed similar properties to volume-activated chloride current. After ClC-3 was knocked-down by ClC-3-siRNA, hypotonicity-activated and paclitaxel-induced chloride currents were obviously decreased, indicating that the chloride channel involved in paclitaxel-induced apoptosis may be ClC-3. In early apoptotic cells, ClC-3 was up-regulated significantly; over-expressed ClC-3 was accumulated in cell membrane to form intercrossed filaments, which were co-localized with ?-tubulins; changes of ultrastructures and decrease of flexibility in cell membrane were detected by atomic force microscopy. These suggest that ClC-3 is a critical target of paclitaxel and the involvement of ClC-3 in apoptosis may be associated with its accumulation with membrane microtubules and its over activation.
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Doppler ultrasound and X-ray-guided percutaneous nephrolithotomy with one-step balloon dilation for complex renal stones.
Urol. Int.
PUBLISHED: 03-04-2013
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To assess the safety and efficacy of combining Doppler ultrasound with X-ray-guided percutaneous nephrolithotomy (PCNL) with one-step balloon dilation for management of complex renal stones.
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Involvement of volume-activated chloride channels in H2O 2 preconditioning against oxidant-induced injury through modulating cell volume regulation mechanisms and membrane permeability in PC12 Cells.
Mol. Neurobiol.
PUBLISHED: 02-26-2013
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The functions of chloride channels in preconditioning-induced cell protection remain unclear. In this report, we show that the volume-activated chloride channels play a key role in hydrogen peroxide (H2O2) preconditioning-induced cell protection in pheochromocytoma PC12 cells. The preconditioning with 100 ?M H2O2 for 90 min protected the cells from injury induced by long period exposure to 300 ?M H2O2. The protective effect was attenuated by pretreatment with the chloride channel blockers, 5-nitro-2-3-phenylpropylamino benzoic acid (NPPB) and tamoxifen. H2O2 preconditioning directly activated a chloride current, which was moderately outward-rectified and sensitive to the chloride channel blockers and hypertonicity-induced cell shrinkage. H2O2 preconditioning functionally up-regulated the activities of volume-activated chloride channels and enhanced the regulatory volume decrease when exposure to extracellular hypotonic challenges. In addition, acute application of H2O2 showed distinctive actions on cell volume and membrane permeability in H2O2 preconditioned cells. In H2O2 preconditioned cells, acute application of 300 ?M H2O2 first promptly induced a decrease of cell volume and enhancement of cell membrane permeability, and then, cell volume was maintained at a relatively stable level and the facilitation of membrane permeability was reduced. Conversely, in control cells, 300 ?M H2O2 induced a slow but persistent apoptotic volume decrease (AVD) and facilitation of membrane permeability. H2O2 preconditioning also significantly up-regulated the expression of ClC-3 protein, the molecular candidate of the volume-activated chloride channel. These results suggest that H2O2 preconditioning can enhance the expression and functional activities of volume-activated chloride channels, thereby modulate cell volume and cell membrane permeability, which may contribute to neuroprotection against oxidant-induced injury.
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Gastrodin production from p-2-hydroxybenzyl alcohol through biotransformation by cultured cells of Aspergillus foetidus and Penicillium cyclopium.
Appl. Biochem. Biotechnol.
PUBLISHED: 02-24-2013
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The objective of this work was to take advantage of the resting cells of suitable fungus as an in vitro model to prepare gastrodin from p-2-hydroxybenzyl alcohol (HBA), which mainly exists in the metabolites of the plant Gastrodia elata Blume. The one-step biotransformation of HBA into gastrodin was examined with the filamentous fungi cells of Aspergillus foetidus and Penicillium cyclopium AS 3.4513 in this study. The fundamental conditions of biotransformation were screened and compared for both fungi. P. cyclopium AS 3.4513 had better gastrodin-producing capability than A. foetidus through one-step bioconversion. The highest yield of gastrodin was 36 mg/L for A. foetidus ZU-G1 and 65 mg/L for P. cyclopium AS 3.4513 under the respective development condition during 6 days of biotransformation. The comparative results show that P. cyclopium AS 3.4513 reveals great potential to form gastrodin using HBA as the precursor. The products catalyzed by the resting cells of P. cyclopium AS 3.4513 were identified through NMR and ESI-MS. Current results can be applied not only to the chemical synthesis processes that may involve the hydroxylation reaction but also to the industrial production. The selected fungus is the potential biocatalyst for HBA glucosylation.
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