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Find video protocols related to scientific articles indexed in Pubmed.
Sevoflurane preconditioning ameliorates neuronal deficits by inhibiting microglial MMP-9 expression after spinal cord ischemia/reperfusion in rats.
Mol Brain
PUBLISHED: 09-04-2014
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Microglia are the primary immune cells of the spinal cord that are activated in response to ischemia/reperfusion (IR) injury and release various neurotrophic and/or neurotoxic factors to determine neuronal survival. Among them, matrix metalloproteinase-9 (MMP-9), which cleaves various components of the extracellular matrix in the basal lamina and functions as part of the blood spinal cord barrier (BSCB), is considered important for regulating inflammatory responses and microenvironmental homeostasis of the BSCB in the pathology of ischemia. Sevoflurane has been reported to protect against neuronal apoptosis during cerebral IR. However, the effects of sevoflurane preconditioning on spinal cord IR injury remain unclear. In this study, we investigated the role of sevoflurane on potential genetic roles of microglial MMP-9 in tight junction protein breakdown, opening of the BSCB, and subsequent recruitment of microglia to apoptotic spinal cord neurons.
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Unbiased proteomic and transcript analyses reveal that Stathmin-1 silencing inhibits colorectal cancer metastasis and sensitizes to 5-Fluorouracil treatment.
Mol. Cancer Res.
PUBLISHED: 07-27-2014
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Colorectal cancer (CRC) metastasis is a major cause of mortality worldwide, which may only be controlled with novel methods limiting tumor dissemination and chemoresistance. High Stathmin-1 (STMN1) expression was previously established as a hallmark of CRC progression and predictor of poor survival; however, the mechanism of action is less clear. This work demonstrates that STMN1 silencing arrests tumor disseminative cascades by inhibiting multiple metastatic drivers, and repressing oncogenic and mesenchymal transcription. Using a sensitive iTRAQ labeling proteomic approach that quantified differential abundance of 4562 proteins, targeting STMN1 expression was shown to reinstate the default cellular program of metastatic inhibition, and promote cellular adhesion via amplification of hemi-desmosomal junctions and intermediate filament tethering. Silencing STMN1 also significantly improved chemoresponse to the classical CRC therapeutic agent, 5FU, via a novel Caspase-6 (CASP6)-dependent mechanism. Interestingly, the prometastatic function of STMN1 was independent of p53 but required phosphorylations at S25 or S38; abrogating phosphorylative events may constitute an alternative route to achieving metastatic inhibition. These findings establish STMN1 as a potential target in anti-metastatic therapy, and demonstrate the power of an approach coupling proteomics and transcript analyses in the global assessment of treatment benefits and potential side-effects. Implications: Stathmin-1 is a potential candidate in colorectal cancer therapy that targets simultaneously the twin problems of metastatic spread and chemoresistance.
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Proteomic analysis of plasma membrane and tonoplast from the leaves of mangrove plant Avicennia officinalis.
Proteomics
PUBLISHED: 07-15-2014
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In order to understand the salt tolerance and secretion in mangrove plant species, gel electrophoresis coupled with LC-MS-based proteomics was used to identify key transport proteins in the plasma membrane (PM) and tonoplast fractions of Avicennia officinalis leaves. PM and tonoplast proteins were purified using two-aqueous-phase partitioning and density gradient centrifugation, respectively. Forty of the 254 PM proteins and 31 of the 165 tonoplast proteins identified were predicted to have transmembrane domains. About 95% of the identified proteins could be classified based on their functions. The major classes of proteins were predicted to be involved in transport, metabolic processes, defense/stress response, and signal transduction, while a few of the proteins were predicted to be involved in other functions such as membrane trafficking. The main classes of transporter proteins identified included H(+) -ATPases, ATP-binding cassette transporters, and aquaporins, all of which could play a role in salt secretion. These data will serve as the baseline membrane proteomic dataset for Avicennia species. Further, this information can contribute to future studies on understanding the mechanism of salt tolerance in halophytes in addition to salt secretion in mangroves. All MS data have been deposited in the ProteomeXchange with identifier PXD000837 (http://proteomecentral.proteomexchange.org/dataset/PXD000837).
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Effects of background electrolytes and ionic strength on enrichment of Cd(II) ions with magnetic graphene oxide-supported sulfanilic acid.
J Colloid Interface Sci
PUBLISHED: 07-11-2014
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To elucidate the influence mechanisms of background electrolytes and ionic strength on Cd(II) removal, the adsorption of Cd(II) onto magnetic graphene oxide-supported sulfanilic acid (MGO-SA) in aqueous solutions containing different types and concentrations of background electrolytes was studied. The results indicate that Cd(II) adsorption was strongly dependent on pH and could be strongly affected by background electrolytes and ionic strength. The Cd(II) removal was decreased with the presence of background electrolyte cations (Na(+), K(+), Ca(2+), Mg(2+), Mn(2+), Zn(2+), and Ni(2+)), and the divalent cations exerted more obvious influences on the Cd(II) uptake than the monovalent cations at pH 6. Both Cl(-) and NO3(-) had negative effects on Cd(II) adsorption because they can form water-soluble metal-anion complexes with Cd(II) ions. The presence of 0.01molL(-1) Na3PO4 reduced the removal percentage of Cd(II) at pH<5 but extremely enhanced the Cd(II) removal when the pH>5. The Cd(II) adsorption was sensitive to changes in the concentration of NaCl, NaNO3, NaClO4, and Na3PO4. Besides, the adsorption isotherm of Cd(II) onto MGO-SA could be well described by the Freundlich model and was also influenced by the type of background electrolyte ions and the ionic strength.
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[Purification and characterization of the biosurfactant rhamnolipid].
Se Pu
PUBLISHED: 07-03-2014
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Biosurfactant rhamnolipid is a metabolic intermediate produced by microorganisms under a certain condition. There are the polar hydrophilic group and the non-polar hydrophobic group in rhamnolipid molecule which always exhibits high surface or interfacial activity. A reliable separation and purification method as well as component identification technique is essential for success of production process. The rhamnolipid was produced by aerobic fermentation using Pseudomonas aeruginosa CCTCC AB93066 in this study. It was separated from the culture by acid precipitation and purified by column chromatography until two groups of monorhamnolipid and dirhamnolipid were obtained. High performance liquid chromatography with mass spectrometry (HPLC-MS) examination showed that either the monorhamnolipid or the dirhamnolipid contained three major species. They were RhaC10C10, RhaC10C12-H2, RhaC10C12 for monorhamnolipid and Rha2C10 C10, Rha2C10 C12-H2, Rha2 C10 C12 for dirhamnolipid. The results of the study suggested that Pseudomonas aeruginosa CCTCC AB93066 is a good strain for rhamnolipid production. Acid precipitation-column chromatography technique is good for purification of rhamnolipid. Meanwhile, HPLC-MS is a reliable method for identifying components of rhamnolipid with high sensitivity and accuracy.
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Traffic congestion in interconnected complex networks.
Phys Rev E Stat Nonlin Soft Matter Phys
PUBLISHED: 06-25-2014
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Traffic congestion in isolated complex networks has been investigated extensively over the last decade. Coupled network models have recently been developed to facilitate further understanding of real complex systems. Analysis of traffic congestion in coupled complex networks, however, is still relatively unexplored. In this paper, we try to explore the effect of interconnections on traffic congestion in interconnected Barabási-Albert scale-free networks. We find that assortative coupling can alleviate traffic congestion more readily than disassortative and random coupling when the node processing capacity is allocated based on node usage probability. Furthermore, the optimal coupling probability can be found for assortative coupling. However, three types of coupling preferences achieve similar traffic performance if all nodes share the same processing capacity. We analyze interconnected Internet autonomous-system-level graphs of South Korea and Japan and obtain similar results. Some practical suggestions are presented to optimize such real-world interconnected networks accordingly.
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JWA gene regulates PANC-1 pancreatic cancer cell behaviors through MEK-ERK1/2 of the MAPK signaling pathway.
Oncol Lett
PUBLISHED: 06-24-2014
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The present study aimed to investigate the role of JWA gene in the proliferation, apoptosis, invasion and migration of PANC-1 pancreatic cancer cells and the effect on the MAPK signaling pathway. Human PANC-1 pancreatic cancer cells were cultured in vitro, and small interfering RNA (siRNA) was designed for the JWA gene. The siRNA was transfected into PANC-1 cells. Subsequently, the cell proliferation was measured by MTT assay; cell apoptosis was detected by analyzing BAX and Bcl-2 protein expression; cell migration and invasion were measured using Transwell(®) chambers; and the protein expression of JWA and ERK1/2, JNK and p38 and their phosphorylated forms were measured by western blotting. By utilizing the MTT assay, the results showed that when JWA protein expression was inhibited, the proliferation of PANC-1 cells was enhanced. In addition, the expression of apoptosis-associated protein (AAP) BAX was substantially decreased, while the expression of the apoptosis inhibitor gene, Bcl-2, was significantly enhanced. Using Transwell chambers, it was found that the number of penetrating PANC-1 cells was significantly increased after transfection with JWA siRNA, suggesting that the migration and invasion of the cells was substantially increased. By studying the association between JWA and the MAPK pathway in PANC-1 cells, it was found that the expression of p-ERK1/2 of the MAPK pathway was significantly downregulated following JWA siRNA transfection. However, the expression levels of ERK1/2, JNK, p38, p-JNK and p-p38 showed no significant differences. In conclusion, it was shown that JWA affects the proliferation, apoptosis, invasion and migration of PANC-1 pancreatic cancer cells which could be attributed to effects on the expression of ERK1/2 in the MAPK pathway.
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A randomized trial comparing weight loss treatment delivered in large versus small groups.
Int J Behav Nutr Phys Act
PUBLISHED: 05-01-2014
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BackgroundBehavioral interventions for obesity are commonly delivered in groups, although the effect of group size on weight loss has not been empirically evaluated. This behavioral weight loss trial compared the 6- and 12-month weight changes associated with interventions delivered in a large group (LG) or small groups (SG).MethodsObese adults (N¿=¿66; mean age¿=¿50 years; mean BMI¿=¿36.5 kg/m2; 47% African American; 86% women) recruited from a health maintenance organization were randomly assigned to: 1) LG treatment (30 members/group), or 2) SG treatment (12 members/group). Conditions were comparable in frequency and duration of treatment, which included 24 weekly group sessions (months 1¿6) followed by six monthly extended care contacts (months 7¿12). A mixed effects model with unstructured covariance matrix was applied to analyze the primary outcome of weight change while accounting for baseline weight and dependence among participants¿ measurements over time.ResultsSG participants lost significantly more weight than LG participants at Month 6 (¿6.5 vs. -3.2 kg; p¿=¿0.03) and Month 12 (¿7.0 vs. -1.7 kg; p¿<¿0.002). SG participants reported better treatment engagement and self-monitoring adherence at Months 6 and 12, ps¿<¿0.04, with adherence fully mediating the relationship between group size and weight loss.ConclusionsReceiving obesity treatment in smaller groups may promote greater weight loss and weight loss maintenance. This effect may be due to improved adherence facilitated by SG interactions. These novel findings suggest that the perceived efficiency of delivering behavioral weight loss treatment to LGs should be balanced against the potentially better outcomes achieved by a SG approach.
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Testing the sensitivities of noncognate inhibitors to varicella zoster virus thymidine kinase: implications for postherpetic neuralgia therapy with existing agents.
J Mol Model
PUBLISHED: 04-27-2014
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Varicella zoster virus (VZV), a member of the human herpesvirus family, affects peripheral or cranial nerves and can reactivate years after the primary infection. Thymidine kinase (TK) is essential for VZV replication, and its active site is highly conserved in the herpesvirus family. A number of small-molecule inhibitors have already been successfully developed that target the TK of herpes simplex virus type 1 (HSV-1), which is one of the most prevalent sexually transmitted infections worldwide. In the present study, we attempted to test the sensitivities of HSV-1 TK inhibitors to their noncognate VZV TK by integrating in silico modeling and an in vitro assay. We tested nine representative HSV-1 TK inhibitors, including three FDA-approved drugs and six compounds that are under clinical development. The structures of the complexes of these inhibitor ligands with HSV-1 TK and noncognate VZV TK had been solved previously by X-ray crystallography or were modeled in the present work using a template-based approach. Subsequently, a rigorous quantum mechanics/molecular mechanics (QM/MM) nonbonded analysis that accounted for the Poisson-Boltzmann/surface area (PB/SA) solvent effect was employed to refine the complex structures and, on this basis, to evaluate the binding potencies of these complexes. As might be expected, the QM/MM-PB/SA-derived free energy was shown to be highly correlated with the HSV-1 TK inhibitory activities of the nine inhibitors. Further, it was found that the HSV-1 TK inhibitors exhibit strong binding affinities for their noncognate VZV TK, although they are still more selective for HSV-1 TK than for VZV TK. In order to test the theoretical results obtained from the computational analysis, we performed an in vitro kinase assay to determine the inhibitory potencies of three commercially available antiviral agents, namely penciclovir, ganciclovir, and aciclovir, against their noncognate target VZV TK, resulting in IC50 values of 86, 127, and 150 ?M respectively, which are modestly weaker than the corresponding values obtained for HSV-1 TK. In addition, visual structure examination and virtual mutation/deletion analysis suggested that the residue Arg222 is present at the active site of HSV-1 TK but not at the active site of VZV TK, which is the reason for the difference in inhibitor selectivity between HSV-1 TK and VZV TK.
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Patient and physician characteristics associated with the provision of weight loss counseling in primary care.
Obes Res Clin Pract
PUBLISHED: 04-19-2014
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A variety of physician and patient characteristics may influence whether weight loss counseling occurs in primary care encounters.
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High throughput sequencing of two celery varieties small RNAs identifies microRNAs involved in temperature stress response.
BMC Genomics
PUBLISHED: 03-24-2014
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MicroRNAs (miRNAs) are small, non-coding RNAs of 20 to 24 nucleotides that regulate gene expression and responses to biotic and abiotic stress. Till now, no reports have previously been published concerning miRNAs in celery.
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Role of the TLR4 pathway in blood-spinal cord barrier dysfunction during the bimodal stage after ischemia/reperfusion injury in rats.
J Neuroinflammation
PUBLISHED: 03-09-2014
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Spinal cord ischemia-reperfusion (I/R) involves two-phase injury, including an initial acute ischemic insult and subsequent inflammatory reperfusion injury, resulting in blood-spinal cord barrier (BSCB) dysfunction involving the TLR? pathway. However, the correlation between TLR?/MyD??-dependent and TLR?/TRIF-dependent pathways in BSCB dysfunction is not fully understood. The aim of this study is to characterize inflammatory responses in spinal cord I/R and the events that define its clinical progression with delayed neurological deficits, supporting a bimodal mechanism of injury.
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Layer-by-layer nanoparticles as an efficient siRNA delivery vehicle for SPARC silencing.
Small
PUBLISHED: 02-08-2014
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Efficient and safe delivery systems for siRNA therapeutics remain a challenge. Elevated secreted protein, acidic, and rich in cysteine (SPARC) protein expression is associated with tissue scarring and fibrosis. Here we investigate the feasibility of encapsulating SPARC-siRNA in the bilayers of layer-by-layer (LbL) nanoparticles (NPs) with poly(L-arginine) (ARG) and dextran (DXS) as polyelectrolytes. Cellular binding and uptake of LbL NPs as well as siRNA delivery were studied in FibroGRO cells. siGLO-siRNA and SPARC-siRNA were efficiently coated onto hydroxyapatite nanoparticles. The multilayered NPs were characterized with regard to particle size, zeta potential and surface morphology using dynamic light scattering and transmission electron microscopy. The SPARC-gene silencing and mRNA levels were analyzed using ChemiDOC western blot technique and RT-PCR. The multilayer SPARC-siRNA incorporated nanoparticles are about 200 nm in diameter and are efficiently internalized into FibroGRO cells. Their intracellular fate was also followed by tagging with suitable reporter siRNA as well as with lysotracker dye; confocal microscopy clearly indicates endosomal escape of the particles. Significant (60%) SPARC-gene knock down was achieved by using 0.4 pmole siRNA/?g of LbL NPs in FibroGRO cells and the relative expression of SPARC mRNA reduced significantly (60%) against untreated cells. The cytotoxicity as evaluated by xCelligence real-time cell proliferation and MTT cell assay, indicated that the SPARC-siRNA-loaded LbL NPs are non-toxic. In conclusion, the LbL NP system described provides a promising, safe and efficient delivery platform as a non-viral vector for siRNA delivery that uses biopolymers to enhance the gene knock down efficiency for the development of siRNA therapeutics.
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Collapsin response mediator proteins: Potential diagnostic and prognostic biomarkers in cancers (Review).
Oncol Lett
PUBLISHED: 02-07-2014
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The collapsin response mediator proteins (CRMPs) were originally identified as mediators of semaphorin 3A signaling and neuronal differentiation. The CRMP family consists of five homologous cytosolic proteins, CRMP1-5. Altered expression levels of CRMPs have been observed in several malignant tumors, including lung, breast, colorectal, prostate, pancreatic and neuroendocrine lung cancer. The aim of the current study was to review the recent progress achieved in understanding the association between the different levels of CRMP expression in tumors and their involvement in pathological functions, such as tumor metastasis, disease progression, subtype differentiation and clinical outcome, to address the potential value of CRMPs as biomarkers for the diagnosis and prognosis of cancer patients.
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Effects of application of corn straw on soil microbial community structure during the maize growing season.
J. Basic Microbiol.
PUBLISHED: 02-07-2014
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This study investigated the influence of corn straw application on soil microbial communities and the relationship between such communities and soil properties in black soil. The crop used in this study was maize (Zea mays L.). The five treatments consisted of applying a gradient (50, 100, 150, and 200%) of shattered corn straw residue to the soil. Soil samples were taken from May through September during the 2012 maize growing season. The microbial community structure was determined using phospholipid fatty acid (PLFA) analysis. Our results revealed that the application of corn straw influenced the soil properties and increased the soil organic carbon and total nitrogen. Applying corn straw to fields also influenced the variation in soil microbial biomass and community composition, which is consistent with the variations found in soil total nitrogen (TN) and soil respiration (SR). However, the soil carbon-to-nitrogen ratio had no effect on soil microbial communities. The abundance of PLFAs, TN, and SR was higher in C1.5 than those in other treatments, suggesting that the soil properties and soil microbial community composition were affected positively by the application of corn straw to black soil. A Principal Component Analysis indicated that soil microbial communities were different in the straw decomposition processes. Moreover, the soil microbial communities from C1.5 were significantly different from those of CK (p?
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A quantitative chemical proteomics approach to profile the specific cellular targets of andrographolide, a promising anticancer agent that suppresses tumor metastasis.
Mol. Cell Proteomics
PUBLISHED: 01-20-2014
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Drug target identification is a critical step toward understanding the mechanism of action of a drug, which can help one improve the drug's current therapeutic regime and expand the drug's therapeutic potential. However, current in vitro affinity-chromatography-based and in vivo activity-based protein profiling approaches generally face difficulties in discriminating specific drug targets from nonspecific ones. Here we describe a novel approach combining isobaric tags for relative and absolute quantitation with clickable activity-based protein profiling to specifically and comprehensively identify the protein targets of andrographolide (Andro), a natural product with known anti-inflammation and anti-cancer effects, in live cancer cells. We identified a spectrum of specific targets of Andro, which furthered our understanding of the mechanism of action of the drug. Our findings, validated through cell migration and invasion assays, showed that Andro has a potential novel application as a tumor metastasis inhibitor. Moreover, we have unveiled the target binding mechanism of Andro with a combination of drug analog synthesis, protein engineering, and mass-spectrometry-based approaches and determined the drug-binding sites of two protein targets, NF-?B and actin.
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Inhibition of tyrosinase activity by polyphenol compounds from Flemingia philippinensis roots.
Bioorg. Med. Chem.
PUBLISHED: 01-14-2014
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Flemingia philippinensis is used as a foodstuff or medicinal plant in the tropical regions of China. The methanol (95%) extract of the roots of this plant showed potent tyrosinase inhibition (80% inhibition at 30?g/ml). Activity-guided isolation yielded six polyphenols that inhibited both the monophenolase (IC50=1.01-18.4?M) and diphenolase (IC50=5.22-84.1?M) actions of tyrosinase. Compounds 1-6 emerged to be three new polyphenols and three known flavanones, flemichin D, lupinifolin and khonklonginol H. The new compounds (1-3) were identified as dihydrochalcones which we named fleminchalcones (A-C), respectively. The most potent inhibitor, dihydrochalcone (3) showed significant inhibitions against both the monophenolase (IC50=1.28?M) and diphenolase (IC50=5.22?M) activities of tyrosinase. Flavanone (4) possessing a resorcinol group also inhibited monophenolase (IC50=1.79?M) and diphenolase (IC50=7.48?M) significantly. In kinetic studies, all isolated compounds behaved as competitive inhibitors. Fleminchalcone A was found to have simple reversible slow-binding inhibition against monophenolase.
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Intrathecal antagonism of microglial TLR4 reduces inflammatory damage to blood-spinal cord barrier following ischemia/reperfusion injury in rats.
Mol Brain
PUBLISHED: 01-08-2014
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Inflammatory reaction in blood-spinal cord barrier (BSCB) plays a crucial role in ischemia/reperfusion (I/R) injury. It has been shown that microglia could be activated through Toll-like receptors (TLRs). Therefore, we hypothesize that TLR4 is involved in the microglial activation and BSCB disruption after I/R.
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Link prediction in complex networks: a mutual information perspective.
PLoS ONE
PUBLISHED: 01-01-2014
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Topological properties of networks are widely applied to study the link-prediction problem recently. Common Neighbors, for example, is a natural yet efficient framework. Many variants of Common Neighbors have been thus proposed to further boost the discriminative resolution of candidate links. In this paper, we reexamine the role of network topology in predicting missing links from the perspective of information theory, and present a practical approach based on the mutual information of network structures. It not only can improve the prediction accuracy substantially, but also experiences reasonable computing complexity.
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Selection of suitable reference genes for qPCR normalization under abiotic stresses in Oenanthe javanica (BI.) DC.
PLoS ONE
PUBLISHED: 01-01-2014
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Accurate normalization of gene expression data is an absolute prerequisite to obtain reliable results in qPCR analysis. Oenanthe javanica, an aquatic perennial herb, belongs to the Oenanthe genus in Apiaceae family, with known medicinal properties. In the current study, O. javanica was subjected to hormone stimuli (gibberellin, salicylic acid, methyl jasmonate, and abscisic acid) and abiotic stresses (heat, cold, salt, and drought), and the expression of nine candidate reference genes (eIF-4?, ACT7, TIP41, GAPDH, SAND, EF-1?, PP2A, TBP, and TUB) was evaluated. Stability of the genes was assessed using geNorm, NormFinder and BestKeeper. All the genes presented distinct expression profiles under the experimental conditions analyzed. Under abiotic stress conditions, ACT7 and PP2A genes displayed the maximum stability; PP2A and SAND were the most stable genes under hormone stimuli. Even though PP2A gene was most stable across all the samples, individual analysis revealed changes in expression profile. To further validate the suitability of the reference genes identified in this study, the expression level of M6PR gene under salt treatment was studied. Based on our data, we propose that it is essential to normalize the target gene expression with specific reference genes under different experimental conditions for most accurate results. To our knowledge, this is the first systematic analysis for reference genes under abiotic stress and hormone stimuli conditions in O. javanica. This will be beneficial for future studies on O. javanica and other plants in Apiaceae family at molecular level.
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Chiral Lewis Acid Catalyzed Asymmetric Cycloadditions of Disubstituted Ketenes for the Synthesis of ?-Lactones and ?-Lactones.
Org. Lett.
PUBLISHED: 12-04-2013
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Highly diastereo- and enantioselective [2 + 2]- and [4 + 2]-cycloadditions of disubstituted ketenes were realized by chiral Lewis acid catalysis. A series of arylalkylketenes underwent the reaction smoothly with isatins and ?,?-unsaturated ?-ketoesters, providing optically active ?-lactones and ?-lactones with vicinal chiral centers in excellent yields (up to 99%) and enantioselectivities (up to 99% ee), as well as exclusively high diastereoselectivities under 0.2-2 mol % catalyst loading.
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Bacterial neuraminidase inhibitory effects of prenylated isoflavones from roots of Flemingia philippinensis.
Bioorg. Med. Chem.
PUBLISHED: 07-05-2013
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Bacterial neuraminidase (NA) is one of the key enzymes involved in pathogenesis of inflammation during infection. The organic extract of the roots of Flemingia philippinensis showed high bacterial NA inhibitory activity with an IC50 of around 5?g/mL. Activity-guided separation of the methanol extract yielded nine prenylated isoflavones together with the novel species isoflavone (2) which was given the name flemingsin. Isolated prenylated isoflavones (1-9) were evaluated for NA inhibition and their IC50 values were determined to range between 0.30 and 56.8?M. The most potent inhibitor 4 (IC50=300nM, Ki=130nM) features a catechol motif in the B-ring and a furan in the A-ring. Structure-activity analysis also showed a 4-hydroxyl group within the B-ring was essential for NA inhibitory activity, because isoflavone (9) having protected 4-hydroxyl group was much less potent than its hydroxylated counterpart. All neuraminidase compounds screened were found to be reversible noncompetitive inhibitors. Furthermore, the most active NA inhibitors (1-9) were proven to be present in the native roots in high quantities by HPLC and LC-DAD-ESI/MS.
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Catalytic Asymmetric Homologation of ?-Ketoesters with ?-Diazoesters: Synthesis of Succinate Derivatives with Chiral Quaternary Centers.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 06-26-2013
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Y not? In the presence of the L/Y(OTf)3 catalyst, the first catalytic asymmetric homologation of ?-ketoesters with ?-alkyl-?-diazoesters through either a 1,2-aryl or 1,2-alkyl shift was accomplished. Highly functionalized succinate derivatives containing a quaternary stereocenter were obtained in excellent yield and enantioselectivity under mild reaction conditions. Tf=trifluoromethanesulfonyl.
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iTRAQ based quantitative proteomics approach validated the role of calcyclin binding protein (CacyBP) in promoting colorectal cancer metastasis.
Mol. Cell Proteomics
PUBLISHED: 03-29-2013
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Keeping continuity with our previous study that revealed direct correlations between CRC metastasis and enhanced CacyBP protein levels, here we attempt to improve our understanding of the mechanisms involved within this enigmatic process. Overexpression of CacyBP (CacyBP-OE) in primary CRC cell and its knock down (CacyBP-KD) in the metastatic CRC cells revealed (through phenotypic studies) the positive impact of the protein on metastasis. Additionally, two individual 4-plex iTRAQ based comparative proteomics experiments were carried out on the CacyBP-OE and CacyBP-KD cells, each with two biological replicates. Mining of proteomics data identified total 279 (63.80% up-regulated and 36.20% down-regulated) proteins to be significantly altered in expression level for the OE set and in the KD set, this number was 328 (48.78% up-regulated and 51.22% down-regulated). Functional implications of these significantly regulated proteins were related to metastatic phenotypes such as cell migration, invasion, adhesion and proliferation. Gene ontology analysis identified integrin signaling as the topmost network regulated within CacyBP-OE. Further detection of caveolar mediated endocytosis in the top hit list correlated this phenomenon with the dissociation of integrins from the focal adhesion complex which are known to provide the traction force for cell movement when transported back to the leading edge. This finding was further supported by the data obtained from CacyBP-KD data set showing down-regulation of proteins necessary for integrin endocytosis. Furthermore, intracellular calcium levels (known to influence integrin mediated cell migration) were found to be lowered in CacyBP-KD cells indicating decreased cell motility and vice versa for the CacyBP-OE cells. Actin nucleation by ARP-WASP complex, known to promote cell migration, was also identified as one of the top regulated pathways in CacyBP-OE cells. In short, this study presents CacyBP as a promising candidate biomarker for CRC metastasis and also sheds light on the underlying molecular mechanism by which CacyBP promotes CRC metastasis.
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Dihydropyrimidinase-like protein 3 expression is negatively regulated by MYCN and associated with clinical outcome in neuroblastoma.
Cancer Sci.
PUBLISHED: 03-17-2013
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Dihydropyrimidinase-like proteins (DPYSLs) are a family of proteins developmentally regulated during maturation of the nervous system. Recently, members of the DPYSL family have been reported to be involved in cancer with low expression of DPYSL1 correlating with poor clinical outcomes in non-small cell lung cancer and functioning as a metastasis suppressor. Neuroblastoma (NB) is a tumor derived from precursor cells of the sympathetic nervous system and is the most common solid tumor in childhood. So far the biological functions of DPYSLs in NB remain elusive. Studying the potential roles of DPYSLs in NB may give us new insights into NB tumorigenesis. In the present study, using antibodies specific to different members of the DPYSL family, DPYSL1, DPYSL2 and DPYSL3, we investigated regulation of their expression and their subcellular distribution during retinoic acid (RA)-induced differentiation in NB cells. The correlation between DPYSLs and MYCN, a biomarker for poor prognosis of NB, was evaluated. We found that DPYSL3 levels increased during RA-induced cell differentiation. Downregulation of MYCN by small interfering RNA (siRNA) increased DPYSL3 levels, while upregulation of MYCN in non-MYCN NB cells decreased DPYSL3 levels. DPYSL1 and DPYSL2 expression didnt change during RA treatment or under different expression levels of MYCN. Moreover, a high level of DPYSL3 mRNA, but not that of DPYSL1 or DPYSL2 mRNA, was detected in tumors from advanced-stage NB that have a better survival. These data indicated that DPYSL3, not DPYSL1 or DPYSL2, is negatively regulated by MYCN and may be used as a potential biomarker for NB.
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Intrathecal transplantation of bone marrow stromal cells attenuates blood-spinal cord barrier disruption induced by spinal cord ischemia-reperfusion injury in rabbits.
J. Vasc. Surg.
PUBLISHED: 03-07-2013
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Intrathecal administration of bone marrow stromal cells has been found to produce beneficial effects on ischemia-reperfusion injury to the spinal cord. The blood-spinal cord barrier is critical to maintain spinal cord homeostasis and neurologic function. However, the effects of bone marrow stromal cells on the blood-spinal cord barrier after spinal cord ischemia-reperfusion injury are not well understood. This study investigated the effects and possible mechanisms of bone marrow stromal cells on blood-spinal cord barrier disruption induced by spinal cord ischemia-reperfusion injury.
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Increased levels of SLP-2 correlate with poor prognosis in gastric cancer.
Gastric Cancer
PUBLISHED: 01-31-2013
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Stomatin-like protein 2 (SLP-2) is a member of the highly conserved stomatin protein family whose homologues span from Archaea to humans and include stomatin, SLP-1, and SLP-3. Several studies have indicated that overexpression of SLP-2 is strongly associated with adhesion and migration in several human cancers. The aim of the present study was to evaluate SLP-2 expression at the mRNA and protein level in patients with gastric cancer (GC) and to examine the relationships between SLP-2 expression, clinicopathological features, and prognosis.
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CTHRC1 is associated with peritoneal carcinomatosis in colorectal cancer: a new predictor for prognosis.
Med. Oncol.
PUBLISHED: 01-03-2013
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Colorectal cancer (CRC) patients with peritoneal carcinomatosis (PC) have a poor prognosis. Over the last decade, increasing evidence has suggested that the Collagen Triple Helix Repeat Containing 1 (CTHRC1) gene is involved in cancer progression and invasion. In this study, we investigated the expression of CTHRC1 in CRC and its potential as a prognostic factor for CRC patients with PC. Microarray analysis of four fresh paired samples showed that the expression of CTHRC1 in peritoneal metastases was higher than that in the corresponding primary tumor. These results were validated using semi-quantitative reverse transcription and polymerase chain reaction. Finally, immunohistochemical analysis showed that CTHRC1 was increased in the peritoneal metastasis group (n = 30) and the primary cancer with peritoneal metastasis group (n = 57) compared to the primary cancer without peritoneal metastasis group (n = 54), both P < 0.001. Cox proportional hazards model analysis showed that high CTHRC1 expression was associated with poor survival (HR = 2.754, P < 0.001, 95 % CI 1.731-4.383). Overall, the results of our study suggest that increased expression of CTHRC1 is associated with PC in CRC patients and could predict poor outcome in CRC patients.
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Racial and geographic disparities in late-stage prostate cancer diagnosis in Florida.
J Health Care Poor Underserved
PUBLISHED: 11-22-2011
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Abstract:Disparities in prostate cancer diagnosis among racial/ethnic groups and across Florida were mapped for the period 1996-2002 and their relationship with putative factors (individual, census tract and county level) was investigated using multilevel modeling and contingency analysis. More counties had higher rates of late-stage diagnosis for Black men than for White men and the location of these racial disparities changed with time. An important finding was the substantially larger correlation between county-level rates for Black and White men in 2002 relatively to 1996, which suggests a convergence in their spatial patterns. Major significant factors for late-stage diagnosis included lack of insurance, low household income, smoking, not being married and presence of farm house. These findings should help the design of intervention programs to target counties with the greatest racial disparities in health outcomes. Additional analysis is needed to disentangle the observed racial/ethnic and geographic differences.
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[Relationship between HBeAg seroconversion with genotypes and HBV specific CTL in patients with chronic hepatitis B treated with Adefovir dipivoxil].
Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi
PUBLISHED: 10-08-2011
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To explore relationship between HBeAg seroconversion with HBV genotypes and HBV specific CTL in patients with chronic hepatitis B (CHB) treated with Adefovir dipivoxil.
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Identification of key players for colorectal cancer metastasis by iTRAQ quantitative proteomics profiling of isogenic SW480 and SW620 cell lines.
J. Proteome Res.
PUBLISHED: 09-19-2011
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This study compared the whole cell proteome profiles of two isogenic colorectal cancer (CRC) cell lines (primary SW480 cell line and its lymph node metastatic variant SW620), as an in vitro metastatic model, to gain an insight into the molecular events of CRC metastasis. Using iTRAQ (isobaric tags for relative and absolute quantitation) based shotgun proteomics approach, we identified 1140 unique proteins, out of which 147 were found to be significantly altered in the metastatic cell. Ingenuity pathway analysis with those significantly altered proteins, revealed cellular organization and assembly as the top-ranked altered biological function. Differential expression pattern of 6 candidate proteins were validated by Western blot. Among these, the low expression level of ?-catenin combined with the up-regulation of CacyBP (Calcyclin binding Protein), a ?-catenin degrading protein, in the metastatic cell provided a rational guide for the downstream functional assays. The relative expression pattern of these two proteins was further validated in three other CRC cells by Western blot and quantitative immunofluorescence studies. Overexpression of CacyBP in three different primary CRC cell lines showed significant reduction in adhesion characteristics as well as cellular ?-catenin level as confirmed by our experiments, indicating the possible involvement of CacyBP in CRC metastasis. In short, this study demonstrates successful application of a quantitative proteomics approach to identify novel key players for CRC metastasis, which may serve as biomarkers and/or drug targets to improve CRC therapy.
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[Male urethral duplication infection: experience with 9 cases].
Zhonghua Nan Ke Xue
PUBLISHED: 09-09-2011
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To study the clinical characteristics of male urethral duplication infection and offer some guidelines for the diagnosis and treatment of the disease.
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Experimental and theoretical evidence of aromatic behavior in heterobenzene-like molecules with metal-metal multiple bonds.
Chemistry
PUBLISHED: 08-04-2011
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Binding two quadruply bonded dimolybdenum units [Mo(2)(DAniF)(3)](+) (DAniF=N,N-di-p-anisylformamidinate) with two chalcogen atoms generated two molecules with a central core composed of a cyclic six-membered [Mo(2)](2)(?-EH)(2) species (E=S in 1 and O in 3, and [Mo(2)] is a quadruple-bonded [Mo(2)(formamidinate)(3)] unit). Aerobic oxidation of 1 and 3 followed by concomitant deprotonation gave rise to the corresponding [Mo(2)](2)(?-E)(2) compounds 2 and 4. The latter show a striking coplanarity and near-bond equalization of the Mo/E cluster. The oxidized species 2 and 4 are diamagnetic in the measured temperature range of 5 to 300 K, which is somewhat unexpected for molecules that have dimetal units with a ?(2)?(4)?(1) electronic configuration. This suggests there are strong interactions between the dimolybdenum units through the E atoms. The large electronic delocalization of the ? electrons over the entire Mo/E core is supported by the exceptionally large potential separation for the two successive one-electron reductions of the linked Mo(2)(5+) units from the oxidized species (?E(½)=1.7 V for the sulfur analogue). This large electronic delocalization has an important effect on the NMR spectroscopic signals for the two sets of methine (N-(CH)-N) protons from the DAniF ligands. Those essentially parallel to the core, H(?), and those essentially perpendicular to the core, H(?), exhibit downfield and upfield chemical shifts, respectively, that are separated by ?=1.32 ppm. The structural, electronic, magnetic, and chemical behaviors for 2 and 4 are consistent with aromaticity, with the [Mo(2)E(2)Mo(2)] cores that resemble the prototypical benzene molecule. Theoretical studies, including DFT calculations, natural bond orbital (NBO) analyses, and gauge-independent atomic orbital (GIAO) NMR spectroscopic calculations, are also consistent with the aromaticity of the [Mo(2)](2)(?-E)(2) units being promoted by d(?)(Mo(2))-p(?)(E) ? conjugation. The cyclic ? conjugation of the central moiety in 2 and 4 involves a total of six electrons with 2e from ?(Mo(2)) and 4e from p(?)(E) orbitals, thereby conforming to Hückels rule when electrons in the MOs with ? character are considered part of the delocalized system.
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Cellular and transcriptomic analysis of human mesenchymal stem cell response to plasma-activated hydroxyapatite coating.
Acta Biomater
PUBLISHED: 07-06-2011
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Atmospheric pressure plasma has recently emerged as a technique with a promising future in the medical field. In this work we used the technique as a post-deposition modification process as a means to activate hydroxyapatite (HA) coatings. Contact angle goniometry, optical profilometry, scanning electron microscopy morphology imaging and X-ray photoelectron spectroscopy analysis demonstrate that surface wettability is improved after treatment, without inducing any concomitant damage to the coating. The protein adsorption pattern has been found to be preferable for MSC, and this may result in greater cell attachment and adhesion to plasma-activated HA than to untreated samples. Cell cycle distribution analysis using flow cytometry reveals a faster transition from G(1) to S phase, thus leading to a faster cell proliferation rate on plasma-activated HA. This indicates that the improvement in surface wettability independently enhances cell attachment and cell proliferation, which is possibly mediated by FAK phosphorylation. Pathway-specific polymerase chain reaction arrays revealed that wettability has a substantial influence on gene expression during osteogenic differentiation of human MSC. Plasma-activated HA tends to enhance this process by systemically deregulating multiple genes. In addition, the majority of these deregulated genes had been appropriately translated, as confirmed by ELISA protein quantification. Lastly, alizarin red staining showed that plasma-activated HA is capable of improving mineralization for up to 3 weeks of in vitro culture. It was concluded from this study that atmospheric pressure plasma is a potent tool for modifying the biological function of a material without causing thermal damage, such that adhesion molecules and drugs might be deposited on the original coating to improve performance.
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Diversity and evolution of four dispersed repetitive DNA sequences in the genus Secale.
Genome
PUBLISHED: 04-16-2011
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We present the first characterization of 360 sequences in six species of the genus Secale of both cultivated and wild accessions. These include four distinct kinds of dispersed repetitive DNA sequences named pSc20H, pSc119.1, pSaO5(411), and pSaD15(940) belonging to the Revolver family. During the evolution of the genus Secale from wild to cultivated accessions, the pSaO5(411)-like sequences became shorter mainly because of the deletion of a trinucleotide tandem repeating unit, the pSc20H-like sequences displayed apparent homogenization in cultivated rye, and the second intron of Revolver became longer. In addition, the pSc20H-, pSc119.1-, and pSaO5(411)-like sequences cloned from wild rye and cultivated rye could be divided into two large clades. No single case of the four kinds of repetitive elements has been inherited by each Secale accession from a lone ancestor. It is reasonable to consider the vertical transmission of the four repetitive elements during the evolution of the genus Secale. The pSc20H- and pSaO5(411)-like sequences showed evolutionary elimination at specific chromosomal locations from wild species to cultivated species. These cases imply that different repetitive DNA sequences have played different roles in the chromosome development and genomic evolution of rye. The present study adds important information to the investigations dealing with characterization of dispersed repetitive elements in wild and cultivated rye.
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Alpha-1 antitrypsin is a potential biomarker for hepatitis B.
Virol. J.
PUBLISHED: 03-30-2011
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Function exertion of specific proteins are key factors in disease progression, thus the systematical identification of those specific proteins is a prerequisite to understand various diseases. Though many proteins have been verified to impact on hepatitis, no systematical protein screening has been documented to hepatitis B virus (HBV) induced hepatitis, hindering the comprehensive understanding to this severe disease.
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Osteoconductivity and growth factor production by MG63 osteoblastic cells on bioglass-coated orthopedic implants.
Biotechnol. Bioeng.
PUBLISHED: 03-29-2011
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We have produced Bioglass coatings for Orthopedic implants by using a novel coating technique, CoBlast. The two resultant surfaces, designated BG and hydroxyapatite (HA)/BG, were compared with their HA counterpart, OsteoZip in terms of osteoblastic cell attachment, adhesion, proliferation, differentiation, and growth factor production. BG and HA/BG were demonstrated by goniometry to be more hydrophilic than OsteoZip. This corresponded to enhanced protein adsorption, cell attachment, and cell adhesion documented by both quantitative and qualitative assessments. BG and HA/BG surfaces had a significant initial release of Si and Ca ions, and this was consistent with elevated cell proliferation and basic fibroblast growth factor levels. However, OsteoZip, being similar to HA/BG, exhibited better osteogenic differentiation than BG did, shown by augmented differentiation marker activity at both protein and mRNA levels. Sandwich ELISA was used to quantify angiopoietin and inducible nitric oxide synthase which are involved in peri-prosthetic angiogenesis and aseptic loosening of total hip replacement, respectively. Both Bioglass-derived coatings provide superior initial osteoconductivity to OsteoZip, and HA/Bioglass composite coating outruns in long-term osteogenic differentiation and prognostic bioprocesses. The novel coatings discovered in this study have significant potential in providing both orthopedic and therapeutic functions.
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In vitro and in vivo bioactivity of CoBlast hydroxyapatite coating and the effect of impaction on its osteoconductivity.
Biotechnol. Adv.
PUBLISHED: 02-24-2011
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The novel non-thermal CoBlast process has been used recently to create a hydroxyapatite coating on metallic substrates with improved biological response compared to an uncoated implant. In this study, we compared the biological effect of coatings deposited by this process and the industrial standard technique - plasma-spray. Physicochemical properties of these two coatings have been found to be significantly different in that CoBlast HA is less rough but more hydrophilic than the plasma-spray HA as evidenced by data obtained from profilometry and goniometry. Mesenchymal stem cell attachment and adhesion are enhanced on CoBlast HA. Analysis by a combination of EDX and ICP suggests that the higher crystallinity retained by the CoBlast HA result in slower coating dissolution. Detailed in vitro evaluation reveals that plasma-spray HA might induce slightly faster cell proliferation and earlier osteogenic differentiation, but CoBlast HA becomes equivalent to it by the late osteogenic stage. PCR array facilitated the identification of differentially regulated genes involved in various functional aspects of in vitro osteogenesis by the CoBlast HA coating. The expression level of the functional protein products of these genes are in agreement with the PCR data. Coating metallic screws with HA significantly improves the in vivo osseointegration. By measuring of removal force using torque measurement instrument and analyzing the patterns found in X-ray images it is demonstrated that the two HA coatings elicit comparable osseointegration. Using simulated impaction model, CoBlast HA is shown to maintain better performance in cell attachment and mineralization than plasma-spray HA, especially following significant impactions. This might indicate a potentially greater osteoconductivity of CoBlast HA coating in shear-stress associated surgical applications. Collectively, it was demonstrated that CoBlast HA is an effective alternative to plasma-spray HA coating and a promising replacement for specialized surgical applications.
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The elements of human cyclin D1 promoter and regulation involved.
Clin Epigenetics
PUBLISHED: 02-11-2011
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Cyclin D1 is a cell cycle machine, a sensor of extracellular signals and plays an important role in G1-S phase progression. The human cyclin D1 promoter contains multiple transcription factor binding sites such as AP-1, NF-?B, E2F, Oct-1, and so on. The extracellular signals functions through the signal transduction pathways converging at the binding sites to active or inhibit the promoter activity and regulate the cell cycle progression. Different signal transduction pathways regulate the promoter at different time to get the correct cell cycle switch. Disorder regulation or special extracellular stimuli can result in cell cycle out of control through the promoter activity regulation. Epigenetic modifications such as DNA methylation and histone acetylation may involved in cyclin D1 transcriptional regulation.
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Multimodal tumor imaging by iron oxides and quantum dots formulated in poly (lactic acid)-D-alpha-tocopheryl polyethylene glycol 1000 succinate nanoparticles.
Biomaterials
PUBLISHED: 01-22-2011
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This work developed a multimodal imaging system by co-encapsulating superparamagnetic iron oxides (IOs) and quantum dots (QDs) in the nanoparticles of poly (lactic acid) - d-?-tocopheryl polyethylene glycol 1000 succinate (PLA-TPGS) for concurrent imaging of the magnetic resonance imaging (MRI) and the fluorescence imaging to combine their advantages and to overcome their disadvantages as well as to promote a sustained and controlled imaging with passive targeting effects to the diseased cells. The QDs and IOs-loaded PLA-TPGS NPs were prepared by a modified nanoprecipitation method, which were then characterized for their size and size distribution, zeta potential and the imaging agent encapsulation efficiency. The transmission electron microscopy (TEM) images showed direct evidence for the well-dispersed distribution of the QDs and IOs within the PLA-TPGS NPs. The cellular uptake and the cytotoxicity of the PLA-TPGS NPs formulation of QDs and IOs were investigated in vitro with MCF-7 breast cancer cells, which were conducted in close comparison with the free QDs and IOs at the same agent dose. The Xenograft model was also conducted for biodistribution of the QDs and IOs-loaded PLA-TPGS NPs among the various organs, which showed greatly enhanced tumor imaging due to the passively targeting effects of the NPs to the tumor. Images of tumors were acquired in vivo by a 7T MRI scanner. Further ex vivo images of the tumors were obtained by confocal laser scanning microscopy. Such a multimodal imaging system shows great advantages of both contrast agents making the resultant probe highly sensitive with good depth penetration, which confirms the diagnosis obtained from each individual imaging. With therapeutics co-encapsulation and ligand conjugation, such nanoparticles system can realize a multi-functional system for medical diagnosis and treatment.
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Electrophysiological correlates of emotional processing in sensation seeking.
Biol Psychol
PUBLISHED: 01-09-2011
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Previous studies have consistently reported a relationship between sensation seeking and emotional reactivity. However, little is known about the neural correlates and the time course of emotional processing in sensation seeking. The present study addressed these issues by recording event-related potentials (ERPs) during an emotional oddball task. Valence effect was significant at N2, P3 and LPP whereas arousal effect was significant at P3 and LPP. More importantly, low sensation seekers (LSSs) exhibited an increased emotional N2 whereas high sensation seekers (HSSs) showed an enhanced emotional P3. Furthermore, the arousal effect was similar across the two groups, but the valence effect at N2 stage was significant in LSSs instead of HSSs. These findings suggest that LSSs tend to show a more active general alerting system toward emotional stimuli, particularly for negative stimuli, whereas HSSs tend to display a stronger preference for intense stimulation irrespective of the emotional valence.
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[The changes in expression of uncoordinated 33-like phosphoprotein 1 and hypoxia-inducible factor-1? in neuroblastoma cells under hypoxic condition].
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue
PUBLISHED: 10-28-2010
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To study the differences in expression of uncoordinated 33-like phosphoprotein 1 (Ulip1) and hypoxia-inducible factor-1? (HIF-1?) in neuroblastoma cell lines that have neuronal characteristics under normoxia and hypoxia conditions.
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What words should we use when discussing excess weight?
J Am Board Fam Med
PUBLISHED: 09-09-2010
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There is limited research on how patients prefer physicians to communicate about the topic of obesity, and there is even less understanding of which terms physicians most commonly use.
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Targeting miRNAs in osteoblast differentiation and bone formation.
Expert Opin. Ther. Targets
PUBLISHED: 08-10-2010
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Bone tissue arises from mesenchymal stromal cells (MSCs) differentiated into the osteoblast lineage by genetic and epigenetic mechanisms. Emerging evidence indicates that the class of small non-coding single-stranded RNAs known as "microRNAs (miRNAs)" also plays a critical role in this process.
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Protective effects of lithium treatment for spatial memory deficits induced by tau hyperphosphorylation in splenectomized rats.
Clin. Exp. Pharmacol. Physiol.
PUBLISHED: 07-28-2010
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1. Postoperative cognitive dysfunction has become more prevalent in recent years. We used a splenectomized rat model with postoperative spatial learning and memory deficits to investigate the role of tau hyperphosphorylation and glycogen synthase kinase-3? (GSK-3?) within the hippocampus. 2. Cognitive function was assessed in a Y-maze 1 day before and 1, 3 and 7 days after surgery. We measured site-specific phosphorylation of hippocampal tau (Thr-205 and Ser-396), GSK-3? activity and expression of interleukin-1? (IL-1?), tumour necrosis factor-? (TNF-?) mRNA and protein as markers of inflammation. We also tested the effects of treatment with lithium chloride (LiCl), a GSK-3? inhibitor. 3. Splenectomy was associated with learning and memory impairment 3 days later, as well as a rapid and massive hyperphosphorylation of hippocampal tau at Thr-205 and Ser-396, activated GSK-3?, and increased IL-1? and TNF-? expression. LiCl completely restored tau hyperphosphorylation to control levels. 4. These data from the splenectomized rat model suggest that inflammatory factors affect tau pathology through the GSK-3? signalling pathway and that LiCl is a promising treatment for postoperative cognitive deficits.
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Maternal factors and disparities associated with oral clefts.
Ethn Dis
PUBLISHED: 06-04-2010
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The epidemiology of oral clefts continually unfolds. Researchers have not reached consensus concerning the significance of maternal smoking, weight gain, diabetes, age, and education and the risk of oral clefts. The purpose of this study was to examine these factors associated with oral clefts in the US population.
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In vitro and in vivo inhibition of neuroblastoma tumor cell growth by AKT inhibitor perifosine.
J. Natl. Cancer Inst.
PUBLISHED: 05-12-2010
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Activated AKT is a marker of decreased event-free or overall survival in neuroblastoma (NB) patients. The aim of this study was to investigate the effect of perifosine, a nontoxic AKT inhibitor, as a single agent on NB cell growth in vitro and in vivo.
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Postoperative cognitive deficits and neuroinflammation in the hippocampus triggered by surgical trauma are exacerbated in aged rats.
Prog. Neuropsychopharmacol. Biol. Psychiatry
PUBLISHED: 04-21-2010
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Postoperative cognitive dysfunction (POCD) is characterized by the progressive deterioration of intellectual/cognitive function following surgery. It has been suggested that the senile brain, which characteristically expresses higher levels of central proinflammatory cytokines, interleukin (IL)-6, IL-1?, and tumor necrosis factor (TNF)-?, is more susceptible to additional insult following surgery. The authors of this study investigated the expression of central cytokines IL-1?, IL-6 and TNF-? and hippocampal glial cell activation in aged and adult rats following partial hepatectomy. Cognitive function was assessed in a reversal-learning version of the Morris water maze (MWM) before and after surgery. Hippocampal pro-inflammatory cytokines IL-1?, IL-6 and TNF-? and glial cell activation markers glial fibrillary acidic protein (GFAP) and S100? were measured at each time point; CD200 and CD200R were also measured to explore potential mechanisms of glial cell activation. Surgical trauma resulted in impairments in distance and latency only on postoperative day 1 (p<0.001, respectively) in adult rats. Aged rats exhibited impairments on day 1 (p<0.001) that persisted until postoperative day 3 (p=0.002 and p=0.001, respectively). All significant impairments paralleled upregulated cytokine IL-1? and IL-6 expression. Immunohistochemistry assay further showed more hippocampal glial cell activation in aged rats compared to that in adults. Overall, these findings suggest that surgical trauma, rather than anesthesia, resulted in cognitive function impairment potentiated by aging. Hippocampal pro-inflammatory cytokines and glial cell activation might mediate trauma-induced POCD.
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Science letters: Proteomic analysis of differentially expressed proteins in mice with concanavalin A-induced hepatitis.
J Zhejiang Univ Sci B
PUBLISHED: 03-06-2010
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To find new protein biomarkers for the detection and evaluation of liver injury and to analyze the relationship between such proteins and disease progression in concanavalin A (Con A)-induced hepatitis.
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NGF activation of TrkA induces vascular endothelial growth factor expression via induction of hypoxia-inducible factor-1?.
Mol. Cell. Neurosci.
PUBLISHED: 02-09-2010
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Communication between the vasculature and nervous system is important during embryogenesis but the molecular mechanisms mediating this are ill-defined. We evaluated the molecular mechanisms by which Nerve Growth Factor (NGF) and Brain-derived neurotrophic factor (BDNF) regulate VEGF production. NGF activation of TrkA causes a marked increase in VEGF secretion by neuronal cells. The NGF induced increase in VEGF is accompanied by an increase in HIF-1?. Pharmacologic inhibitors of the Trk tyrosine kinase, PI-3 kinase and mTOR paths prevent NGF stimulated increases in HIF-1? and VEGF. NGF induced increase in VEGF transcription is dependent on a hypoxia response element (HRE) in the VEGF promoter. Mutation of the HRE or siRNA mediated silencing of HIF-1? expression blocks NGF induced increases in VEGF transcription. In primary cultures of TrkA expressing neurons from dorsal root ganglion, NGF induces VEGF expression that is accompanied by increases in HIF-1? but not HIF-2? expression. In CGN neurons, BDNF induces VEGF that is dependent on induction of HIF-1?. Our study indicates that neurotrophin activation of Trk stimulates an increase in VEGF transcription that is mediated by induction of HIF-1?.
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Systemic perfluorohexane attenuates lung injury induced by lipopolysaccharide in rats: the role of heme oxygenase-1.
Pharmacol Rep
PUBLISHED: 01-24-2010
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Clinical trials with partial liquid ventilation demonstrate improvement in oxygenation, as well as some adverse side effects linked to the application of liquid perfluorocarbons (PFCs) during liquid ventilation. Thus, we examined the effects of systemic administration of PFC on acute lung injury (ALI) induced by lipopolysaccharide (LPS) and its effects on heme oxygenase-1 (HO-1), a compound that provides potent cytoprotection against lung injury. Rats were assigned to one of six groups (n = 8). Thirty minutes after they were challenged with LPS aerosol inhalation, perfluorohexane was given intraperitoneally every two hours. Ten hours after LPS inhalation, bronchoalveolar lavage fluid (BALF) and lung tissue were obtained for enzyme linked immunosorbent assay, histologic, and Western-blot analyses. The results showed that perfluorohexane significantly decreased the wet to dry weight ratio, malondialdehyde (MDA) production, and myeloperoxidase (MPO) activity in the lung tissue. Also, perfluorohexane reduced the total protein content and levels of tumor necrosis factor-alpha (TNF-alpha) but increased the levels of the anti-inflammatory cytokine interleukin-10 (IL-10) in the BALF, resulting in decreased pulmonary edema and the infiltration of neutrophils into the lung tissues of LPS-treated rats. Furthermore, perfluorohexane increased HO-1 protein production and stimulated HO-1 activity in the lung tissue. Pre-treatment with Zinc protoporphyrin IX, an inhibitor of HO-1, decreased the protective effects of perfluorohexane in rats. In summary, systemic perfluorohexane alleviates LPS-induced lung injury in rats, and HO-1 may be involved in the mechanism of this reduction.
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[Influence of adefovir dipivoxil on HBV specific CTL in patients with chronic hepatitis B].
Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi
PUBLISHED: 01-06-2010
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To explore the influence of adefovir dipivoxil on HBV specific CTL in patients with chronic hepatitis B (CHB).
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A novel microRNA targeting HDAC5 regulates osteoblast differentiation in mice and contributes to primary osteoporosis in humans.
J. Clin. Invest.
PUBLISHED: 05-12-2009
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MicroRNAs (miRNAs) interfere with translation of specific target mRNAs and are thought to thereby regulate many cellular processes. Recent studies have suggested that miRNAs might play a role in osteoblast differentiation and bone formation. Here, we identify a new miRNA (miR-2861) in primary mouse osteoblasts that promotes osteoblast differentiation by repressing histone deacetylase 5 (HDAC5) expression at the post-transcriptional level. miR-2861 was found to be transcribed in ST2 stromal cells during bone morphogenetic protein 2-induced (BMP2-induced) osteogenesis, and overexpression of miR-2861 enhanced BMP2-induced osteoblastogenesis, whereas inhibition of miR-2861 expression attenuated it. HDAC5, an enhancer of runt-related transcription factor 2 (Runx2) degradation, was confirmed to be a target of miR-2861. In vivo silencing of miR-2861 in mice reduced Runx2 protein expression, inhibited bone formation, and decreased bone mass. Importantly, miR-2861 was found to be conserved in humans, and a homozygous mutation in pre-miR-2861 that blocked expression of miR-2861 was shown to cause primary osteoporosis in 2 related adolescents. Consistent with the mouse data, HDAC5 levels were increased and Runx2 levels decreased in bone samples from the 2 affected individuals. Thus, our studies show that miR-2861 plays an important physiological role in osteoblast differentiation and contributes to osteoporosis via its effect on osteoblasts.
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Simultaneous determination of six herbal components in intestinal perfusate by high-performance liquid chromatography.
Biomed. Chromatogr.
PUBLISHED: 03-25-2009
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An effective, accurate and reliable HPLC with UV detection method was developed and validated for quantitation of six components: baicalin, berberine hydrochloride, quercetin, kaempferol, isorhamnetin and baicalein in intestinal perfusate using rotundin as an internal standard. The chromatographic separation was performed on a Welchrom-C(18) column (250 x 4.6 mm i.d. with 5.0 microm particle size) with a mobile phase consisting of acetonitrile, water, phosphoric acid and triethylamine (30:70:0.2:0.1,v/v) at a flow rate of 1.0 mL/min and a UV detection at 270 nm. The method had a chromatographic run time of 30 min and excellent linear behavior over the investigated concentration ranges observed with the values of r higher than 0.99 for all the analytes. The lower limit of quantification of the analytical method was 0.09 microg/mL for berberine hydrochloride, quercetin, kaempferol and baicalein and 0.18 microg/mL for baicalin and isorhamnetin. The intra- and inter-day precisions measured at three concentration levels were all less than 10% for all analytes. The bias ranged from -6.91 to 4.33%. The validated method has been successfully applied to investigate the rat intestine absorption profiles of baicalin, berberine hydrochloride, quercetin, kaempferol, isorhamnetin and baicalein.
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Relationship between self-efficacy and physical activity among patients with type 2 diabetes.
J Behav Med
PUBLISHED: 01-06-2009
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While previous studies indicate a significant relationship between self-efficacy and physical activity, less research has focused on this relationship among patients with type 2 diabetes. The purpose of this investigation was to examine whether self-efficacy mediated the relationship between participation in a 1-month, print-based physical activity intervention and improvements in activity levels.
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Clinicopathological significance of NMIIA Overexpression in Human Gastric Cancer.
Int J Mol Sci
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Altered expressions of nonmuscle myosin IIA (NMIIA) have been observed in certain types of cancers, but the impact of the alterations in gastric cancer (GC) remains unclear. The purpose of this study was to evaluate the expression of NMIIA at the mRNA and protein level in patients with GC and to assess its clinical significance. We investigated the expression of NMIIA in fresh, paired GC tissues by reverse transcriptase polymerase chain reaction (RT-PCR; n = 14) and Western blot analysis (n = 36). Simultaneously, we performed immunohistochemistry (IHC) on paraffin embedded specimens, including 96 GC specimens, 30 matched normal specimens and 30 paired metastatic lymph node samples. NMIIA is overexpressed in GC compared with the adjacent normal gastric epithelium (p < 0.001) and high-level NMIIA expression is significantly correlated with the depth of wall invasion, lymph node metastasis, distant metastasis and Tumor Node Metastasis (TNM) stage. Furthermore, elevated NMIIA expression is an independent prognostic factor in multivariate analysis using the Cox regression model (p = 0.021). These findings indicate that overexpression of NMIIA may contribute to the progression and poor prognosis of GC.
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Fatal pulmonary embolism in a patient with thromboembolism of the internal jugular vein after liver transplant.
Prog Transplant
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A patient with acute liver failure and thromboembolism of the internal jugular vein subsequently had a massive pulmonary embolism and died 25 days after orthotopic liver transplant. The primary cause of death was massive pulmonary embolus. This case report highlights the need for clinicians to be aware that fatal embolic events can occur in liver transplant recipients, even when routine prophylactic procedures are implemented. The benefits and risks of invasive strategies, including placement of superior vena cava filters, should be considered on a case-by-case basis.
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High ADAM8 expression is associated with poor prognosis in patients with hepatocellular carcinoma.
Pathol. Oncol. Res.
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In this study,we investigated the ADAM8 expression in hepatocellular carcinoma (HCC) and its correlation with clinicopathologic features,including the survival of patients with HCC. Furthermore,we examined the biological processes regulated by ADAM8 during the development of using HepG2 cell line as a model system. We used immunohistochemistry to compare ADAM8 protein expression in HCC and normal liver tissues and further analyze the ADAM8 protein expression in clinicopathologically characterized 105 HCC cases.We stably knocked down the endogenous expression level of ADAM8 in HepG2 cells with specific shRNA-expressing lentiviral vector. Following the successful establishment of stable cells,we examined in vitro cell growth by MTT assay,anchorage-independent growth by soft-agar colony formation assay and cell migration/invasion by transwell and boyden chamber assay. And in addition,we also investigated the in vivo tumor growth by xenograft transplantation of HepG2 cells into nude mice. Protein expression level of ADAM8 was markedly higher in HCC tissues than that in the normal liver tissues (P?=?0.0058).In addition,high expression of ADAM8 protein was positively correlated with serum AFP elevation,tumor size,histological differentiation,tumor recurrence,tumor metastasis,and tumor stage. Patients with higher ADAM8 expression showed a significantly shorter overall survival time than patients with low ADAM8 expression. Multivariate analysis suggested that ADAM8 expression might be an independent prognostic indicator (p?=?0.016) for the survival of patients with HCC. ADAM8-specific shRNA (shADAM8) successfully knocked down its endogenous expression in HepG2 cells. Compared to the parental and control shRNA-transfected (shCtrl) HepG2 cells,the shADAM8 cells exhibited significantly reduced in vitro cell growth,anchorage-independent growth,cell migration and invasion (p?
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Fabrication of positively charged poly(ethylene glycol)-diacrylate hydrogel as a bone tissue engineering scaffold.
Biomed Mater
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To improve cell attachment and to understand the effects of positive charge on the behavior of osteoblasts, 2-(methacryloyloxy)ethyl-trimethylammonium chloride (MAETAC), a positively charged monomer, was incorporated into poly(ethylene glycol)-diacrylate (PEGDA) hydrogel. The physicochemical properties of the resultant polymers, including the degree of acrylation of PEGDA, pKa of MAETAC, swelling ratio, zeta potential, and protein adsorption were investigated. Meanwhile, osteoblast-like MC3T3-E1 cells were seeded on the hydrogel to evaluate the effect of the positive charge on the behavior of the cells, including attachment, proliferation, and differentiation. The results revealed that PEGDA was synthesized with 90 percent of acrylation and MAETAC had been successfully incorporated into PEGDA. The pKa value of MAETAC was 9.4 determined by acid-based titration. The electrically charged nature of modified hydrogels was confirmed by zeta potential. With increasing concentration of MAETAC, the swelling ratio of the hydrogel in deionized water increased, while the swelling ratio stayed constant in phosphate buffer solution. The protein adsorption of the hydrogel also increased with increasing concentration of MAETAC. The modification of positive charge not only enhanced the attachment and proliferation of osteoblast-like MC3T3-E1 cells on the hydrogel, but also up-regulated alkaline phosphatase activity in the cells as well as gene expression of focal adhesion kinase and osteogenic markers, including collagen I, osteopontin, and osteocalcin. These findings indicate that the positively charged PEGDA may not only be a promising scaffold candidate for bone tissue engineering, but also a good platform to study the effect of positive charge on cell behavior due to the controllable charge density.
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Expression of ADAM8 and its clinical values in diagnosis and prognosis of hepatocellular carcinoma.
Tumour Biol.
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ADAM8 behaves as an active metalloprotease in vitro, hydrolyzing myelin basic protein and a variety of peptide substrates based on the cleavage sites of membrane-bound cytokines, growth factors, and receptors. Other studies have demonstrated overexpression of some ADAM family proteins in a variety of human tumors, but no report is available on the actual expression of ADAM8 and the correlation between clinicopathologic features and prognosis of hepatocellular carcinoma (HCC) patients. In this study, serum levels of ADAM8 were measured by ELISA in 126 patients with HCC, 50 patients with liver cirrhosis (LC), and 50 healthy individuals. The expression of ADAM8 in liver tissue was further studied using Western blotting in 126 patients with HCC and 50 with LC. The correlations between ADAM8 status and various clinicopathological parameters including survival were analyzed. Survival analysis was performed using the Kaplan-Meier method and Coxs proportional hazards model. The ELISA assay showed that the serum levels of ADAM8 in the HCC, LC, and healthy groups were 136.4 ± 34.5, 64.2 ± 20.1, and 63.2 ± 22.7 U/ml, respectively. Analysis of variance was used for inter-group comparison, and differences were found between the HCC group and the other two groups (both P < 0.001), while no difference was found between the LC group and the healthy group (P = 0.365). Western blotting assay showed that ADAM8 protein expression was detected in 62.7 % (79/126) HCC and in 32 % (16/50) LC tissues. Further, ADAM8 expression was associated closely with serum AFP elevation, tumor size, histological differentiation, tumor recurrence, tumor metastasis, and tumor stage. Kaplan-Meier survival analysis showed that patients with ADAM8-positive tumors had a shorter postoperative survival time than those with ADAM8-negative tumors (P < 0.001). Multivariate analysis revealed that ADAM8 expression was an independent prognostic parameter for the overall survival rate of HCC patients. These findings provide evidence that the expression of ADAM8 serves as a poor prognostic biomarker for HCC. ADAM8 may be a potential target of antiangiogenic therapy for HCC.
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Pretransplant neurological presentation and severe posttransplant brain injury in patients with acute liver failure.
Transplantation
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Alterations in the central nervous system in patients with acute liver failure (ALF) present unique challenges in the perioperative period. In this retrospective study, we examined pretransplant neurological presentation and the incidence, clinical presentation, and risk factors associated with severe posttransplant brain injury (BI) in ALF patients undergoing orthotopic liver transplantation (OLT).
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High expression of ADAM8 correlates with poor prognosis in hepatocellular carcinoma.
Surgeon
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To evaluate the association between ADAM8 tissue expression and patient prognosis in hepatocellular carcinoma (HCC).
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Overexpression of HOXA1 correlates with poor prognosis in patients with hepatocellular carcinoma.
Tumour Biol.
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HOXA1 overexpression is sufficient for malignant transformation of nontumorigenic epithelial cells. It is known that HOXA1, which was upregulated in squamous cell carcinomas, affects both cell growth and death. The forced expression of HOXA1 in human breast cancer cells results in increased cell growth activity. However, it has not been reported in hepatocellular carcinoma (HCC). In this study, we used immunohistochemistry to compare HOXA1 protein expression in HCC and normal liver tissues and further analyzed HOXA1 protein expression in 156 clinicopathologically characterized HCC cases. We stably knocked down the endogenous expression level of HOXA1 in HepG2 cells with specific shRNA-expressing lentiviral vector. Following the successful establishment of stable cells, we examined in vitro cell growth by the MTT assay, anchorage-independent growth through a soft agar colony formation assay and cell migration/invasion by transwell and Boyden chamber assay. In addition, we also investigated in vivo tumor growth by xenograft transplantation of HepG2 cells into nude mice. Our results showed that the protein expression level of HOXA1 was markedly higher in HCC tissues than that in normal liver tissue (P = 0.019). In addition, a high expression level of HOXA1 protein was positively correlated with the T classification (P < 0.001), the N classification (P < 0.001), distant metastasis (P = 0.004), and the clinical stage (P < 0.001) of HCC patients. Patients with higher HOXA1 expression showed a significantly shorter overall survival time compared with patients with low HOXA1 expression. Multivariate analysis suggested that HOXA1 expression might be an independent prognostic indicator (P < 0.001) for the survival of patients with HCC. HOXA1-specific shRNA (shHOXA1) successfully knocked down HOXA1 endogenous expression in HepG2 cells. Compared to the parental and control shRNA-transfected (shCtrl) HepG2 cells, the shHOXA1 cells exhibited significantly reduced in vitro cell growth, anchorage-independent growth, and cell migration and invasion (P < 0.05). In vivo, the xenograft transplants from shHOXA1 cells gave rise to much smaller tumors compared with those from shCtrl cells. Collectively, high HOXA1 expression is associated with poor overall survival in patients with HCC. The downregulation of HOXA1 inhibits growth, anchorage-independent growth, and migration and invasion of HepG2 cells.
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High RIN1 expression is associated with poor prognosis in patients with gastric adenocarcinoma.
Tumour Biol.
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The aim of this study was to investigate the expression and prognostic significance of RIN1 in gastric adenocarcinoma. RIN1 expression was analyzed using quantitative real-time PCR (qRT-PCR), Western blotting, and immunohistochemical staining on tissue samples from a consecutive series of 315 gastric adenocarcinoma patients who underwent tumor resections between 2003 and 2006. The relationship between RIN1 expression, clinicopathological factors, and patient survival was investigated. qRT-PCR results showed that the RIN1 mRNA expression was higher in tumor tissue samples than in the adjacent normal tissues, and a corresponding increase in protein expression was confirmed by Western blotting. Immunohistochemical staining indicated that RIN1 is highly expressed in 54.3 % of gastric adenocarcinomas. RIN1 expression levels were closely associated with tumor size, histological differentiation, tumor stage, and lymph node involvement. Kaplan-Meier survival analysis showed that high RIN1 expression exhibited a significant correlation with poor prognosis for gastric adenocarcinoma patients. Multivariate analysis revealed that RIN1 expression is an independent prognostic parameter for the overall survival rate of gastric adenocarcinoma patients. Our data suggest that RIN1 plays an important role in gastric adenocarcinoma progression and that a high RIN1 expression predicts an unfavorable prognosis in gastric adenocarcinoma patients.
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PRAF3 induces apoptosis and inhibits migration and invasion in human esophageal squamous cell carcinoma.
BMC Cancer
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Prenylated Rab acceptor 1 domain family member 3 (PRAF3) is involved in the regulation of many cellular processes including apoptosis, migration and invasion. This study was conducted to investigate the effect of PRAF3 on apoptosis, migration and invasion in human esophageal squamous cell carcinoma (ESCC).
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Abnormally long-range diamagnetic anisotropy induced by cyclic d(?)-p(?) ? conjugation within a six-membered dimolybdenum/chalcogen ring.
Inorg Chem
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Incorporating two quadruply bonded dimolybdenum units [Mo(2)(DAniF)((3))](+) (ancillary ligand DAniF = N,N-di-p-anisylformamidinate) with two hydroselenides (SeH(-)) gave rise to [Mo(2)(DAniF)(3)](2)(?-SeH)(2) (1). With the molecular scaffold remaining unchanged, aerobic oxidation of 1, followed by autodeprotonation, generated [Mo(2)(DAniF)(3)](2)(?-Se)(2) (2). The two complexes share a common cyclic six-membered Mo(2)/Se core, but compound 2 is distinct from 1 by having structural, electronic, and magnetic properties that correspond with aromaticity. Importantly, the aromatic behaviors for this non-carbon system are ascribable to the bonding analogy between the ? component in a Mo-Mo quadruple bond and the ? component in a C-C double bond. Cyclic ? delocalization via d(?)-p(?) conjugation within the central unit, which involves six ? electrons with one electron from each of the Mo(2) units and two electrons from each of the bridging atoms, has been confirmed in a previous work on the oxygen- and sulfur-bridged analogues (Fang, W.; et al. Chem.-Eur. J.2011, 17, 10288). Of the three members in this family, compound 2 exhibits an enhanced aromaticity because of the selenium bridges. The remote in-plane and out-of-plane methine (ArNCHNAr) protons resonate at chemical shifts (?) 9.42 and 7.84 ppm, respectively. This NMR displacement, ?? = 1.58 ppm, is larger than that for the oxygen-bridged (1.30 ppm) and sulfur-bridged (1.49 ppm) derivatives. The abnormally long-range shielding effects and the large diamagnetic anisotropy for this complex system can be rationalized by the induced ring currents circulating the Mo(2)/chalcogen core. By employment of the McConnell equation {?? = ??[(l - 3 cos 2?)/3R(3)N]}, the magnetic anisotropy (?? = ?(?) - ?(||)) is estimated to be -414 ppm cgs, which is dramatically larger than -62.9 ppm cgs for benzene, the paradigm of aromaticity. In addition, it is found that the magnitude of ?? is linearly related to the radius of the bridging atoms, with the selenium analogue having the largest value. This aromaticity sequence is in agreement with that for the chalcogen-containing aromatic family, e.g., furan < thiophene < selenophene.
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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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