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Find video protocols related to scientific articles indexed in Pubmed.
In vitro investigation of a tissue-engineered cell-tendon complex mimicking the transitional architecture at the ligament-bone interface.
J Biomater Appl
PUBLISHED: 10-15-2014
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Restoration of the transitional ligament-bone interface is critical for graft-bone integration. We postulated that an allogenic scaffold mimicking the fibrogenic, chondrogenic, and osteogenic transition gradients could physiologically promote ligament-bone incorporation. The aim of this study was to construct and characterize a composite tendon scaffold with a continuous and heterogeneous transition region mimicking a native ligament insertion site. Genetically modified heterogeneous cell populations were seeded within specific regions of decellularized rabbit Achilles tendons to fabricate a stratified scaffold containing three biofunctional regions supporting fibrogenesis, chondrogenesis, and osteogenesis. The observed morphology, architecture, cytocompatibility, and biomechanics of the scaffolds demonstrated their improved bio-physico-chemical properties. The formation of the transitional regions was augmented via enhanced delivery of two transcription factors, sex determining region Y-box 9 and runt-related transcription factor 2, which also triggered early up-regulated expression of cartilage- and bone-relevant markers, according to quantitative PCR and immunoblot analyses. Gradient tissue-specific matrix formation was also confirmed within the predesignated regions via histological staining and immunofluorescence assays. These results suggest that a transitional interface could be replicated on an engineered tendon through stratified tissue integration. The scaffold offers the advantages of a multitissue transition involving controlled cellular interactions and matrix heterogeneity, which can be applied for the regeneration of the ligament-bone interface.
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Real-time Imaging of Axonal Transport of Quantum Dot-labeled BDNF in Primary Neurons.
J Vis Exp
PUBLISHED: 10-07-2014
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BDNF plays an important role in several facets of neuronal survival, differentiation, and function. Structural and functional deficits in axons are increasingly viewed as an early feature of neurodegenerative diseases, including Alzheimer's disease (AD) and Huntington's disease (HD). As yet unclear is the mechanism(s) by which axonal injury is induced. We reported the development of a novel technique to produce biologically active, monobiotinylated BDNF (mBtBDNF) that can be used to trace axonal transport of BDNF. Quantum dot-labeled BDNF (QD-BDNF) was produced by conjugating quantum dot 655 to mBtBDNF. A microfluidic device was used to isolate axons from neuron cell bodies. Addition of QD-BDNF to the axonal compartment allowed live imaging of BDNF transport in axons. We demonstrated that QD-BDNF moved essentially exclusively retrogradely, with very few pauses, at a moving velocity of around 1.06 ?m/sec. This system can be used to investigate mechanisms of disrupted axonal function in AD or HD, as well as other degenerative disorders.
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Standard b-value versus low b-value diffusion-weighted MRI in renal cell carcinoma: a systematic review and meta-analysis.
BMC Cancer
PUBLISHED: 09-16-2014
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We sought to determine the comparative diagnostic performance of standard b-value (800-1000 s/mm2) versus low b-value (400-500 s/mm2) diffusion-weighted magnetic resonance imaging (DW-MRI) in the detection of renal cell carcinoma (RCC).
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[Agrobacterium-mediated transformation of LJAMP2 gene into 'Red Sun' kiwifruit and its molecular identification].
Sheng Wu Gong Cheng Xue Bao
PUBLISHED: 09-13-2014
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Bacterial canker caused by Pseudomonas syringae pv. Actinidiae is one of the most important diseases of kiwifruit (Actinidia chinensis) and leads to considerable yield losses. In order to obtain transgenic plants with resistance for 'Red Sun' kiwifruit to canker disease, a non-specific lipid transfer protein-like antimicrobial protein gene (LJAMP2) from motherwort (Leonurus japonicus) was introduced into 'Red Sun' kiwifruit through Agrobacterium-mediated transformation. After two days of co-cultivation with A. tumefaciens strain LBA4404 harboring 35S:LJAMP2, the transformed explants were transferred to the selection medium containing 25 mg/L kanamycin+3.0 mg/L BA+1.0 mg/L NAA. The regeneration efficiency of kanamycin-resistant shoots reached to 85%. All (100%) of kanamycin-resistant shoots rooted on half-strength MS medium supplemented with 0.8 mg/L IBA and a total of 40 regenerated plantlets were obtained. PCR and histochemical GUS activity analysis show that 23 of 40 lines (57.50%) were positive, suggesting that the LJAMP2 gene was integrated into the genome of 'Red Sun' kiwifruit. Taken together, we established an efficient genetic transformation method for 'Red Sun' kiwifruit using A. tumefaciens and the transformation frequency reached 5.11%. This protocol will be useful for the genetic breeding of 'Red Sun' kiwifruit for improvement of disease resistance.
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Apoptotic effects of psiRNA-STAT3 on 4T1 breast cancer cells in vitro.
Asian Pac. J. Cancer Prev.
PUBLISHED: 08-30-2014
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The aim of this study was to investigate the effect of a Lipofectamine2000 (Life2000) Transfection Reagent transfected psiRNA-STAT3 plasmid on 4T1 breast cancer cells.
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Vertebroplasty versus kyphoplasty in osteoporotic vertebral compression fracture: a meta-analysis of prospective comparative studies.
Int Orthop
PUBLISHED: 08-28-2014
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The goal of this article is to evaluate the efficacy and the safety of the percutaneous vertebroplasty (PVP) versus percutaneous kyphoplasty (PKP) in dealing with the osteoporotic vertebral compression fracture (OVCF).
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Deposition of Particles in Human Mouth-Throat Replicas and a USP Induction Port.
J Aerosol Med Pulm Drug Deliv
PUBLISHED: 08-19-2014
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Abstract Background: Oral inhalation is the common route of drug delivery to pulmonary airways. In general, deposition in the oropharyngeal airways from a drug-delivery device makes up a substantial portion of the emitted dose, which affects the dose delivered to the lung. Studies with airway replicas made from cadaver or magnetic resonance imaging scans show that for micrometer-sized particles, impaction is the dominant deposition mechanism. Several deposition studies in oropharyngeal replicas found that the deposition efficiency can be correlated with the mouth inlet velocity and inlet mouthpiece diameter. Other studies show that the deposition efficiency is best correlated with the mean diameter of internal geometry and the mean velocity based on the mean diameter. Method: We investigated the mouth inlet diameter, as well as internal airway dimensions and their influence on oropharyngeal deposition based on experimental data from this study. Several human oropharyngeal replicas with different mouth inlet diameters and the USP induction port were used. Results: We found that the aerosol deposition increased with decreasing mouth inlet diameter. Several mathematical expressions were tried to correlate the deposition efficiency with the Stokes number calculated based on (1) mouth inlet diameter and inlet velocity, (2) mean diameter of internal geometry and mean velocity, (3) mouth inlet velocity and mean diameter, and (4) mouth inlet velocity and minimum diameter in the oropharyngeal replica. The best correlation was obtained in case 4. Conclusions: This correlation could explain the intra-subject variation when deposition was found to vary with mouth inlet diameter, such as in some aerosol drug-delivery devices. It could also explain the intersubject variability in oropharyngeal deposition when human volunteers with different airway geometries and mouth openings were studied.
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Significance of Preoperative Planning Simulator for Junior Surgeons' Training of Pedicle Screw Insertion.
J Spinal Disord Tech
PUBLISHED: 07-31-2014
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A prospective study to access the significance of preoperative planning simulator for junior surgeons' training of pedicle screw insertion.
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[Effect of intravenous mannitol or dexamethasone on low back and leg pain after lumbar fusion surgery].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 07-31-2014
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To compare the effect of intravenous 20% mannitol or dexamethasone (DM) on low back and leg pain after minimally invasive transforaminal lumbar interbody fusion (MI-TLIF).
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Gender differences in the clinical characteristics of traumatic spinal fractures among the elderly.
Arch Gerontol Geriatr
PUBLISHED: 07-17-2014
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In order to illustrate the epidemiology of traumatic spinal fractures among the elderly, with an emphasis on exploring gender differences in clinical characteristics, we retrospectively reviewed hospital records on all elderly patients with traumatic spinal fractures who were 60 years of age or older at two university-affiliated hospitals between January 2001 and December 2010. A total of 642 elderly patients with traumatic spinal fractures were identified, of whom 249 were male and 393 were female. Accidental falls from low heights were the most common cause of traumatic spinal fractures among the elderly (50.8%). Frequencies of falls from high heights and direct collisions with a blunt object were significantly higher in male than in female elderly patients (P<0.05). Frequencies of falls from low heights, daily life injuries and jolt injuries in female patients were significantly higher than in male patients (P<0.05). There were 984 vertebral body fractures, with the thoracolumbar segment involved in 60.3% of cases (227/984). Frequencies of cervical spinal fractures, spinal cord injuries, associated non-spinal injuries (ASOIs) and mean injury severity scores (ISSs) were significantly higher in males than in females (P<0.05). Frequencies of thoracic and thoracolumbar spinal fractures in females were significantly higher than in males (P<0.05). Clinicians should make their diagnoses and direct their injury prevention strategies according to gender differences in the clinical characteristics of traumatic spinal fractures among the elderly.
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Comparison of Open Versus Percutaneous Pedicle Screw Fixation Using the Sextant System in the Treatment of Traumatic Thoracolumbar Fractures.
J Spinal Disord Tech
PUBLISHED: 07-16-2014
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We retrospectively reviewed 100 patients who were posterior stabilized without graft fusion. Using the Sextant system, 22 patients underwent minimally invasive short-segment 4 pedicle screw fixation (MIF 4) and 39 patients underwent minimally invasive short-segment combined with intermediate screws fixation that is 6 pedicle screw fixation (MIF 6). The conventional open posterior short-segment 4 pedicle screw fixation (OPF 4) technique was used in 39 patients.
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Optimization of manganese peroxidase production from Schizophyllum sp. F17 in solid-state fermentation of agro-industrial residues.
Sheng Wu Gong Cheng Xue Bao
PUBLISHED: 07-11-2014
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Manganese peroxidase (MnP), a crucial enzyme in lignin degradation, has wide potential applications in environmental protection. However, large-scale industrial application of this enzyme is limited due to several factors primarily related to cost and availability. Special attention has been paid to the production of MnP from inexpensive sources, such as lignocellulosic residues, using solid-state fermentation (SSF) systems. In the present study, a suitable SSF medium for the production of MnP by Schizophyllum sp. F17 from agro-industrial residues has been optimized. The mixed solid medium, comprising pine sawdust, rice straw, and soybean powder at a ratio of 0.52:0.15:0.33, conferred a maximum enzyme activity of 11.18 U/g on the sixth day of SSF. The results show that the use of wastes such as pine sawdust and rice straw makes the enzyme production more economical as well as helps solve environmental problems.
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Effects of the facial interface on inhalation and deposition of micrometer particles in calm air in a child airway model.
Inhal Toxicol
PUBLISHED: 07-03-2014
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How the facial interface affects particle inhalability and depositions within the airway is not well understood. Previous studies of inhalation dosimetry are limited to either inhalability or deposition, rather than the two studied in a systematic way.
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Expression of programmed death 1 is correlated with progression of osteosarcoma.
APMIS
PUBLISHED: 06-11-2014
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Accumulating bodies of evidence indicate that immune dysregulation plays a key role in the development of osteosarcoma (OS). Programmed death 1 (PD-1) is a surface receptor expressed on activated and exhausted T cells, which mediate T-cell inhibition upon binding with its ligand. Researches on PD-1 and OS remain extremely limited. Here, we investigated whether PD-1 could be involved in the development of OS. Expression of PD-1 was measured by flow cytometry on peripheral CD4+ and CD8+ T cells from 56 OS cases and 42 healthy controls. Data revealed that percentages of PD-1 were significantly upregulated on both peripheral CD4+ and CD8+ T cells from OS patients (p < 0.001 and p < 0.001, respectively). Patients with different tumor locations did not present obvious variations in PD-1 level. However, patients with metastasis showed significantly higher level of PD-1 on CD4+ T cells than those without metastasis (p < 0.001). Furthermore, PD-1 expression on CD4+ T cells started to increase in stage III, whereas PD-1 expression on CD8+ T cells started to increase in stage II. In addition, patients with pathological fracture were observed to have elevated PD-1 on both CD4+ and CD8+ T cells. These data suggest that PD-1 is involved in the pathogenesis of OS, especially in the progression of disease.
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Core-shell PLGA/collagen nanofibers loaded with recombinant FN/CDHs as bone tissue engineering scaffolds.
Connect. Tissue Res.
PUBLISHED: 06-10-2014
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Poly(lactic-co-glycolic acid) (PLGA)/collagen nanofibrous scaffolds have been utilized in the tissue engineering field. It has been shown that both fibronectin (FN) and cadherin 11 (CDH) play important roles in the progress of osteogenesis and cell adhesion. The aim of this study was to fabricate recombinant FN/CDHs (rFN/CDHs)-loaded PLGA/collagen nanofibrous scaffolds and evaluate their effects on the adhesion and differentiation of human bone marrow mesenchymal stem cells (hMSCs). PLGA/collagen nanofibers were made by coaxial electrospinning. The morphology and mechanical properties of PLGA/collagen nanofibrous mats were analyzed by scanning electron microscopy and mechanical testing, respectively. The performance of scaffolds was evaluated in terms of the viability, morphology, and osteogenic gene expression levels of hMSCs. rFN/CDHs was successfully incorporated into the PLGA/collagen nanofibers. The release of rFN/CDHs from PLGA nanofibers was investigated by liquid chromatography-mass spectrometry. rFN/CDHs improved the mechanical properties of the PLGA/collagen nanofibers. The controlled release of rFN/CDHs can enhance the proliferation of hMSCs and induce osteogenic gene expression (alkaline phosphatase, RUNX2, and osteocalcin). Our data imply that rFN/CDHs may induce hMSCs differentiation into osteoblasts and PLGA/collagen nanofibers loaded with rFN/CDHs have potential in bone tissue engineering.
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Biomechanical comparison of interspinous distraction device and facet screw fixation system on the motion of lumbar spine: a finite element analysis.
Chin. Med. J.
PUBLISHED: 06-04-2014
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A large amount of biomechanical and clinical evidence from previous studies suggest the efficiency of the two different posterior lumber non-fusion methods, interspinous distraction device (ISDD) and facet screw fixation system (FSS), but the biomechanical comparison of ISDD and FSS has not been thoroughly clarified.
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miR824-Regulated AGAMOUS-LIKE16 Contributes to Flowering Time Repression in Arabidopsis.
Plant Cell
PUBLISHED: 05-29-2014
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The timing of flowering is pivotal for maximizing reproductive success under fluctuating environmental conditions. Flowering time is tightly controlled by complex genetic networks that integrate endogenous and exogenous cues, such as light, temperature, photoperiod, and hormones. Here, we show that AGAMOUS-LIKE16 (AGL16) and its negative regulator microRNA824 (miR824) control flowering time in Arabidopsis thaliana. Knockout of AGL16 effectively accelerates flowering in nonvernalized Col-FRI, in which the floral inhibitor FLOWERING LOCUS C (FLC) is strongly expressed, but shows no effect if plants are vernalized or grown in short days. Alteration of AGL16 expression levels by manipulating miR824 abundance influences the timing of flowering quantitatively, depending on the expression level and number of functional FLC alleles. The effect of AGL16 is fully dependent on the presence of FLOWERING LOCUS T (FT). Further experiments show that AGL16 can interact directly with SHORT VEGETATIVE PHASE and indirectly with FLC, two proteins that form a complex to repress expression of FT. Our data reveal that miR824 and AGL16 modulate the extent of flowering time repression in a long-day photoperiod.
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Urocortin-2 suppression of p38-MAPK signaling as an additional mechanism for ischemic cardioprotection.
Mol. Cell. Biochem.
PUBLISHED: 05-07-2014
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Urocortin-2 (UCN2) is cardioprotective in ischemia/reperfusion injury (I/R) through short-lived activation of ERK1/2. Key factors involved in I/R, e.g. apoptosis, mitochondrial damage, p38 kinase, and Bcl-2 family, have not been well-investigated in UCN2-induced cardioprotection. We assessed the role of p38-MAPK in anti-apoptotic Bcl-2 signaling and mitochondrial stabilization as a putative mechanisms in UCN2-induced cardioprotection. Isolated hearts from adult Sprague-Dawley rats and cultured H9c2 cells were subjected to I/R protocols with or without 10 nM UCN2 treatment. The effect of a specific p38 inhibitor SB202190 was tested in H9c2 cells. Cardiac function, LDH release, and mitochondrial membrane potential (MMP) were used to assess the degree of myocardial injury in hearts and H9c2 cells. Post-perfusion, hearts were collected for Western blot analyses or mitochondria/cytosol isolation to analyze p38 activation and Bcl-2 family members. UCN2 treatment improved rate-pressure product (58 ± 5 vs. 31 ± 4 % of Baseline; P < 0.05) and decreased LDH release (20 ± 9 vs. 90 ± 40 mU/ml LDH, P < 0.01) at the end of 60 min reperfusion. UCN2 reduced phospho-p38 levels and Bax activation. UCN2 increased the expression of Bcl-2 and inhibited the accumulation of p-Bim. With additional experiments, it was confirmed that UCN2 increases the phosphorylation of ERK1/2 in the early phase of UCN2 treatment and increases the overshot recovery of ERK1/2 phosphorylation during reperfusion. UCN2 and SB202190 partially prevented the loss of MMP induced by I/R. However, combined treatment with UCN2 and SB202190 did not provide additive benefit. UCN2 is cardioprotective in I/R in association with reduced phosphorylation of p38 together with the increased ERK1/2 activation and increased Bcl-2 family member pro-survival signaling. These changes may stabilize cardiac mitochondria, similar to p38 inhibitors, as part of a pro-survival mechanism during I/R.
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Minimally invasive transforaminal interbody fusion surgery for the old fracture of the thoracolumbar junction.
J Spinal Disord Tech
PUBLISHED: 05-06-2014
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Retrospective analysis of the clinical outcomes of 15 patients with the old thoracolumbar junction fracture treated by minimally invasive surgery (MIS) transforaminal interbody fusion surgery.
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QTL mapping of adult-plant resistance to leaf rust in a RIL population derived from a cross of wheat cultivars Shanghai 3/Catbird and Naxos.
Theor. Appl. Genet.
PUBLISHED: 04-28-2014
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Six QTL for adult plant resistance to leaf rust, including two QTL effective against additional diseases, were identified in a RIL population derived from a cross between Shanghai 3/Catbird and Naxos. Leaf rust is an important wheat disease and utilization of adult-plant resistance (APR) may be the best approach to achieve long-term protection from the disease. The CIMMYT spring wheat line Shanghai 3/Catbird (SHA3/CBRD) showed a high level of APR to Chinese Puccinia triticina pathotypes in the field. To identify APR genes in this line, a mapping population of 164 recombinant inbred lines (RILs) was developed from a cross of this line and Naxos, a moderately susceptible German cultivar. The RILs were evaluated for final disease severity (FDS) at Baoding, Hebei province, and Zhoukou, Henan province, in the 2010-2011 and 2011-2012 cropping seasons. QTL analysis detected one major QTL derived from SHA3/CBRD on chromosome 2BS explaining from 15 to 37 % of the phenotypic variance across environments. In addition one minor resistance QTL on chromosome 1AL from SHA3/CBRD and four minor QTL from Naxos on chromosomes 2DL, 5B, 7BS, and 7DS were also detected. SHA3/CBRD also possessed seedling resistance gene Lr26, and Naxos contained Lr1 based on gene postulation following tests with an array of P. triticina pathotypes and molecular marker assays. These seedling resistance and APR genes and their closely linked molecular markers are potentially useful for improving leaf rust resistance in wheat breeding programs.
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Structural Basis for Low-Affinity Binding of Non-R2 Carboxylate-Substituted Tricyclic Quinoline Analogs to CK2?: Comparative Molecular Dynamics Simulation Studies.
Chem Biol Drug Des
PUBLISHED: 04-14-2014
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Protein kinase CK2 is a novel potential target for cancer treatment. The tricyclic quinoline compound CX-4945 (R2 = COOH) is the first bioavailable CK2 inhibitor used in human clinical trials for advanced solid tumors. CX-4945 analogs with non-R2 carboxylate function were demonstrated to be approximately 5000-fold less potent than compound 12 (R2 = COOH) in vitro. Molecular docking and molecular dynamics simulations were employed to elucidate the structural mechanisms through which the R2 non-ionizable and R3 carboxylic acid substituents influence binding affinity. Results show that the structure of CK2? and the orientation of ligands changed to different degrees in non-R2 carboxylate function systems. The inappropriate electrostatic interactions between the non-R2 carboxylate group and the positive region lead to improper protein-ligand recognition, which is followed by the reorientation of tricyclic skeletons. For CK2?, the affected positions are distributed over the glycine-rich loop (G-loop), C-loop, and the ?4/?5 loop. The allosteric mechanisms between the deviated ligands and the changed regions are proposed. Detailed energy calculation and residue-based energy decomposition indicate the energetic influences on the contributions of the critical residues. These results are in accordance with one another and could provide rational clues to the design of more potent CK2 inhibitors.
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[Evaluation of treatment for chronic low back pain].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 04-04-2014
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To review the present clinical evaluation of treatment for chronic low back pain.
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Histopathological changes in supraspinous ligaments, ligamentum flava and paraspinal muscle tissues of patients with ankylosing spondylitis.
Int J Rheum Dis
PUBLISHED: 03-07-2014
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To examine the histopathological changes in spinal tissues of ankylosing spondylitis (AS) patients.
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The safety and efficacy of minimally invasive discectomy: a meta-analysis of prospective randomised controlled trials.
Int Orthop
PUBLISHED: 03-06-2014
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The objective of this study was to compare the safety and efficacy of minimally invasive discectomy (MID) with standard discectomy (SD) and determine whether the use of the MID technique could decrease the recurrence of lumbar disc herniation (LDH) after the surgery.
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Acetylcholine-triggered cargo release from supramolecular nanovalves based on different macrocyclic receptors.
Chemistry
PUBLISHED: 03-04-2014
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Acetylcholine (ACh), a neurotransmitter located in cholinergic synapses, can trigger cargo release from mesoporous silica nanoparticles equipped with calixarene- or pillarene-based nanovalves by removing macrocycles from the stalk components. The amount and speed of cargo release can be controlled by varying the concentration of ACh in solution or changing the type of gating macrocycle. Although this proof-of-concept study is far from a real-life application, it provides a possible route to treat diseases related to the central nervous system.
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Silybum marianum oil attenuates oxidative stress and ameliorates mitochondrial dysfunction in mice treated with D-galactose.
Pharmacogn Mag
PUBLISHED: 02-21-2014
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Silybum marianum has been used as herbal medicine for the treatment of liver disease, liver cirrhosis, and to prevent liver cancer in Europe and Asia since ancient times. Silybum marianum oil (SMO), a by-product of silymarin production, is rich in essential fatty acids, phospholipids, sterols, and vitamin E. However, it has not been very good development and use.
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Improved oral bioavailability of breviscapine via a Pluronic P85-modified liposomal delivery system.
J. Pharm. Pharmacol.
PUBLISHED: 02-12-2014
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Breviscapine, a hydrophobic drug used for treating cardiovascular disease, was encapsulated in liposomes to improve its pharmaceutical characteristics. This study describes a novel liposome composition approach to specifically inhibit the P-glycoprotein efflux system.
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Migration inhibitory factor enhances inflammation via CD74 in cartilage end plates with Modic type 1 changes on MRI.
Clin. Orthop. Relat. Res.
PUBLISHED: 02-04-2014
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Type 1 Modic changes are characterized by edema, vascularization, and inflammation, which lead to intervertebral disc degeneration. Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine closely related to the inflammatory cytokines detected in degenerative intervertebral disc tissues. However, the existence and role of MIF and its receptor CD74 in intervertebral disc degeneration have not been elucidated.
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Upregulation of peripheral CD4+CXCR5+ T cells in osteosarcoma.
Tumour Biol.
PUBLISHED: 01-22-2014
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Immune dysregulation plays a key role in the development of osteosarcoma (OS). Peripheral blood CD4+CXCR5+ T cells can induce B-cell activation and produce various cytokines and therefore may play critical roles in tumorigenesis. The purpose of the study was to investigate changes of peripheral CD4+CXCR5+ T cells in OS. Peripheral CD4+CXCR5+ T cells and its subtypes were determined by measuring CD3, CD4, CXCR5, CXCR3, and CCR6 in 38 OS patients and 42 healthy controls using flow cytometry. Data demonstrated that percentage of peripheral CD4+CXCR5+ T cells was significantly increased in OS patients (13.9 %) than in controls (8.6 %, p<0.001). Further analysis identified a profound skewing of peripheral CD4+CXCR5+ T cell subsets toward Th2 and Th17 cells in OS patients. Investigating clinical status of the patients showed that prevalence of peripheral CD4+CXCR5+ T cells was significantly elevated in cases with metastasis (17.4 %) than those without metastasis (12.7 %). Similarly, patients with high tumor grade revealed increased percentage of CD4+CXCR5+ T cells compared to those with low tumor grade (15.3 versus 11.0 %). Interestingly, the upregulation of peripheral CD4+CXCR5+ T cells in patients with metastasis or high tumor grade was contributed by Th1 and Th17 subtypes. This study suggests the involvement of peripheral CD4+CXCR5+ T cells in the pathogenesis and progression of OS and provides novel knowledge for understanding this disease.
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mTORC2 phosphorylation of Akt1: a possible mechanism for hydrogen sulfide-induced cardioprotection.
PLoS ONE
PUBLISHED: 01-01-2014
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Hydrogen sulfide (H2S) is known to have cardiac protective effects through Akt activation. Akt acts as a 'central sensor' for myocyte survival or death; its activity is regulated by multiple kinases including PI3K, mTORC2, PDK1 and phosphatases including PTEN, PP2A and PHLPPL. Based on the previous finding that PI3K inhibitor LY294002 abolishes H2S-induced Akt phosphorylation and cardioprotection, it is accepted that PI3K is the mediator of H2S-induced Akt phosphorylation. However, LY294002 inhibits both PI3K and mTOR, and PI3K only recruits Akt to the membrane where Akt is phosphorylated by Akt kinases. We undertook a series of experiments to further evaluate the role of mTORC2, PDK1, PTEN, PP2A and PHLPPL in H2S-induced Akt phosphorylation and cardioprotection, which, we believe, has not been investigated before. Hearts from adult Sprague-Dawley rats were isolated and subjected to (i) normoxia, (ii) global ischemia and (iii) ischemia/reperfusion in the presence or absence of 50 µM of H2S donor NaHS. Cardiac mechanical function and lactate dehydrogenase (LDH) release were assessed. All hearts also were Western analyzed at the end of perfusion for Akt and a panel of appropriate Akt regulators and targets. Hearts pretreated with 50 µM NaHS had improved function at the end of reperfusion (Rate pressure product; 19±4×10(3) vs. 10±3×10(3) mmHg/min, p<0.05) and reduced cell injury (LDH release 19±10 vs. 170±87 mU/ml p<0.05) compared to untreated hearts. NaHS significantly increased phospho-Akt, phospho-mTOR, phospho-Bim and Bcl-2 in reperfused hearts (P<0.05). Furthermore using H9c2 cells we demonstrate that NaHS pretreatment reduces apoptosis following hypoxia/re-oxygenation. Importantly, PP242, a specific mTOR inhibitor, abolished both cardioprotection and protein phosphorylation in isolated heart and reduced apoptotic effects in H9c2 cells. Treating hearts with NaHS only during reperfusion produced less cardioprotection through a similar mechanism. These data suggest mTORC2 phosphorylation of Akt is a key mediator of H2S-induced cardioprotection in I/R.
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Treatment of unstable thoracolumbar fractures through short segment pedicle screw fixation techniques using pedicle fixation at the level of the fracture: a finite element analysis.
PLoS ONE
PUBLISHED: 01-01-2014
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To compare the von Mises stresses of the internal fixation devices among different short segment pedicle screw fixation techniques to treat thoracic 12 vertebral fractures, especially the mono-segment pedicle screw fixation and intermediate unilateral pedicle screw fixation techniques.
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PSSP-RFE: accurate prediction of protein structural class by recursive feature extraction from PSI-BLAST profile, physical-chemical property and functional annotations.
PLoS ONE
PUBLISHED: 01-01-2014
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Protein structure prediction is critical to functional annotation of the massively accumulated biological sequences, which prompts an imperative need for the development of high-throughput technologies. As a first and key step in protein structure prediction, protein structural class prediction becomes an increasingly challenging task. Amongst most homological-based approaches, the accuracies of protein structural class prediction are sufficiently high for high similarity datasets, but still far from being satisfactory for low similarity datasets, i.e., below 40% in pairwise sequence similarity. Therefore, we present a novel method for accurate and reliable protein structural class prediction for both high and low similarity datasets. This method is based on Support Vector Machine (SVM) in conjunction with integrated features from position-specific score matrix (PSSM), PROFEAT and Gene Ontology (GO). A feature selection approach, SVM-RFE, is also used to rank the integrated feature vectors through recursively removing the feature with the lowest ranking score. The definitive top features selected by SVM-RFE are input into the SVM engines to predict the structural class of a query protein. To validate our method, jackknife tests were applied to seven widely used benchmark datasets, reaching overall accuracies between 84.61% and 99.79%, which are significantly higher than those achieved by state-of-the-art tools. These results suggest that our method could serve as an accurate and cost-effective alternative to existing methods in protein structural classification, especially for low similarity datasets.
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A robust H.264/AVC video watermarking scheme with drift compensation.
ScientificWorldJournal
PUBLISHED: 01-01-2014
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A robust H.264/AVC video watermarking scheme for copyright protection with self-adaptive drift compensation is proposed. In our scheme, motion vector residuals of macroblocks with the smallest partition size are selected to hide copyright information in order to hold visual impact and distortion drift to a minimum. Drift compensation is also implemented to reduce the influence of watermark to the most extent. Besides, discrete cosine transform (DCT) with energy compact property is applied to the motion vector residual group, which can ensure robustness against intentional attacks. According to the experimental results, this scheme gains excellent imperceptibility and low bit-rate increase. Malicious attacks with different quantization parameters (QPs) or motion estimation algorithms can be resisted efficiently, with 80% accuracy on average after lossy compression.
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Long term expansion of bone marrow-derived hMSCs on novel synthetic microcarriers in xeno-free, defined conditions.
PLoS ONE
PUBLISHED: 01-01-2014
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Human mesenchymal stem cells (hMSCs) present an attractive target for cell therapy given their wide availability, immunomodulatory properties, and multipotent nature for differentiation into chondrocytes, osteocytes, and adipocytes. With the progression of hMSC clinical studies, there is an increasing demand for development of technologies that enable efficient cell scale-up into clinically relevant quantities. Commercial scale manufacturing of hMSCs will require a large surface area which is not cost effective with available two-dimensional culture vessels. Recent studies showed that microcarriers provide a three-dimensional culture environment suitable for hMSC expansion. Traditionally, biological coatings and/or serum-containing medium are required to facilitate hMSC attachment and expansion in dynamic conditions. These limitations may hinder the use of microcarriers as a scale-up technology for hMSC therapeutics, where cell products, and therefore patient safety, are more controlled with the use of xeno-free, defined culture conditions. Here we report the long term culture of hMSCs on novel synthetic Synthemax II microcarriers in two different xeno-free media. Cells were maintained over 40 days on sterile, ready-to-use microcarriers in spinner flasks with programmed agitation. hMSC expansion was obtained by addition of fresh beads without the need for enzymatic dissociation. We achieved a cumulative cell expansion of >10,000 fold, and cells retained normal hMSC phenotype, karyotype, and tri-lineage differentiation potential. To our knowledge, this report is the first example of long term culture of hMSCs on synthetic microcarriers in xeno-free, defined conditions.
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[Study on anti-aging effect of ginsenoside Rg1 in serial transplantation of hematopoietic stem cells and progenitor cells].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 12-31-2013
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To investigate the anti-aging effect of ginsenoside R1 in serial transplantation of hematopoietic stem cells and progenitor cells.
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[Percutaneous anterior odontoid and transarticular screw fixation for type II odontoid fractures in elderly patients].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 11-28-2013
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To retrospectively analyze the effectiveness of percutaneous anterior odontoid and transarticular screw fixation for type II odontoid fracture treated in the elderly patients.
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Utilization of Stem Cells in Alginate for Nucleus Pulposus Tissue Engineering.
Tissue Eng Part A
PUBLISHED: 11-16-2013
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In a general view of anatomy, intervertebral disc is composed of three parts: annulus fibrosus (AF), nucleus pulposus (NP), and cartilage endplate (CEP). Recently, several types of stem cells were successfully isolated from these corresponding regions, but up to now, no research was performed about which kind of stem cells is the most efficient candidate for NP tissue engineering or for stem cell-based disc regeneration therapy. In this study, we compared the regenerative potentials of the above-mentioned three kinds of disc-derived stem cells with that of the classic bone marrow (BM)-mesenchymal stem cells (MSCs) in a rabbit disc degeneration model. By magnetic resonance imaging (MRI), X-ray, histology, etc. evaluations, we found that cartilage endplate-derived stem cells (CESCs) showed superior capacity compared with the annulus fibrosus-derived stem cells (AFSCs), nucleus pulposus-derived stem cells (NPSCs), and BM-MSCs (p<0.05); additionally, when comparing the CESC group with the normal control group, there existed no statistical difference in X-ray (p>0.05). Those results demonstrated that the CESC-seeded alginate construct performed the most powerful ability for NP regeneration, while AFSCs showed the most inferior potency, NPSCs and BM-MSCs had similar regenerative capacity and located in the middle. All in all, our study showed that CESCs might act as an efficient seed cell source for NP tissue engineering, which paved a new way for the biological solution of disc degeneration diseases.
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EphB4-Targeted Imaging with Antibody h131, h131-F(ab)2 and h131-Fab.
Mol. Pharm.
PUBLISHED: 11-07-2013
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Accumulating evidence suggests that overexpression of the tyrosine kinase receptor EphB4, a mediator of vascular development, is a novel target for tumor diagnosis, prognosis and therapy. Noninvasive imaging of EphB4 expression could therefore be valuable for evaluating disease course and therapeutic efficacy at the earliest stages of anti-EphB4 treatment. In this study, we systematically investigated the use of anti-EphB4 antibody h131 (150 kDa) and its fragments (h131-F(ab)2, 110 kDa; h131-Fab, 50 kDa) for near-infrared fluorescence (NIRF) imaging of EphB4 expression in vivo. h131-F(ab)2 and h131-Fab were produced through pepsin and papain digestion of h131 respectively, whose purity was confirmed by FPLC and SDS-PAGE. After conjugation with Cy5.5, in vivo characteristics of h131, h131-F(ab)2 and h131-Fab were evaluated in EphB4-positive HT29 tumor model. Although h131-Cy5.5 demonstrated highest tumor uptake among these probes, its optimal tumor uptake level was obtained at 2 days post injection (p.i.). For h131-Fab-Cy5.5, maximum tumor uptake was achieved at 4 h p.i. However, no significant difference was observed between h131-Fab-Cy5.5 and hIgG-Fab-Cy5.5, indicating the tumor accumulation was mainly caused by passive targeting. In contrast, h131-F(ab)2-Cy5.5 demonstrated prominent tumor uptake at 6 h p.i. The target specificity was confirmed by hIgG-F(ab)2-Cy5.5 control and immunofluorescent staining. Collectively, h131-F(ab)2 exhibited prominent and specific tumor uptake at early time points, which suggests it is a promising agent for EphB4-targeted imaging.
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Highly luminescent S, N co-doped graphene quantum dots with broad visible absorption bands for visible light photocatalysts.
Nanoscale
PUBLISHED: 10-24-2013
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A facile hydrothermal synthesis route to N and S, N co-doped graphene quantum dots (GQDs) was developed by using citric acid as the C source and urea or thiourea as N and S sources. Both N and S, N doped GQDs showed high quantum yield (78% and 71%), excitation independent under excitation of 340-400 nm and single exponential decay under UV excitation. A broad absorption band in the visible region appeared in S, N co-doped GQDs due to doping with sulfur, which alters the surface state of GQDs. However, S, N co-doped GQDs show different color emission under excitation of 420-520 nm due to their absorption in the visible region. The excellent photocatalytic performance of the S, N co-doped GQD/TiO2 composites was demonstrated by degradation of rhodamine B under visible light. The apparent rate of S, N:GQD/TiO2 is 3 and 10 times higher than that of N:GQD/TiO2 and P25 TiO2 under visible light irradiation, respectively.
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Application of the random ball test for calibrating slope-dependent errors in profilometry measurements.
Appl Opt
PUBLISHED: 10-03-2013
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Optical profilometers such as scanning white light interferometers and confocal microscopes provide high-resolution measurements and are widely utilized in many fields for measuring surface topography. Slope-dependent systematic errors can be present in the measurement and can be the same order of magnitude as features on the surface to be measured. We propose a self-calibration technique, the random ball test (RBT), for calibrating slope-dependent errors of such instruments. The calibration result can be used to compensate future measurements of similar spherical geometries such as profiles of refractive microlenses. A simulation study validates the approach and shows that the RBT is effective in practical limits. We demonstrate the calibration on a 50× confocal microscope and find a surface slope-dependent bias that increases monotonically with the magnitude of the surface slope and is as large as ?800??nm at a surface slope of 12°. The uncertainty of the calibration is smaller than the observed measurement bias and is dominated by residual random noise. Effects such as drift and ball radius uncertainty were investigated to understand their contribution to the calibration uncertainty.
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Influence of fluoride treatment on surface properties, biodegradation and cytocompatibility of Mg-Nd-Zn-Zr alloy.
J Mater Sci Mater Med
PUBLISHED: 09-24-2013
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Fluoride treatment is a commonly used technique or pre-treatment to optimize the degradation kinetic and improve the biocompatibility of magnesium-based implant. The influence of changed surface properties and degradation kinetics on subsequent protein adsorption and cytocompatibility is critical to understand the biocompatibility of the implant. In this study, a patent magnesium alloy Mg-Nd-Zn-Zr alloy (JDBM) designed for cardiovascular stent application was treated by immersion in hydrofluoric acid. A 1.5 ?m thick MgF2 layer was prepared. The surface roughness was increased slightly while the surface zeta potential was changed to a much more negative value after the treatment. Static contact angle test was performed, showing an increase in hydrophilicity and surface energy after the treatment. The MgF2 layer slowed down in vitro degradation rate, but lost the protection effect after 10 days. The treatment enhanced human albumin adsorption while no difference of human fibrinogen adsorption amount was observed. Direct cell adhesion test showed many more live HUVECs retained than bare magnesium alloy. Both treated and untreated JDBM showed no adverse effect on HUVEC viability and spreading morphology. The relationship between changed surface characteristics, degradation rate and protein adsorption, cytocompatibility was also discussed.
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Monoclonal Antibody against Cell Surface GRP78 as a Novel Agent in Suppressing PI3K/AKT Signaling, Tumor Growth, and Metastasis.
Clin. Cancer Res.
PUBLISHED: 09-18-2013
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The ER chaperone GRP78 translocates to the surface of tumor cells and promotes survival, metastasis, and resistance to therapy. An oncogenic function of cell surface GRP78 has been attributed to the activation of the phosphoinositide 3-kinase (PI3K) pathway. We intend to use a novel anti-GRP78 monoclonal antibody (MAb159) to attenuate PI3K signaling and inhibit tumor growth and metastasis.
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Analysis of ascarosides from Caenorhabditis elegans using mass spectrometry and NMR spectroscopy.
Methods Mol. Biol.
PUBLISHED: 09-10-2013
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The nematode Caenorhabditis elegans secretes a family of water-soluble small molecules, known as the ascarosides, into its environment and uses these ascarosides in chemical communication. The ascarosides are derivatives of the 3,6-dideoxysugar ascarylose, modified with different fatty acid-derived side chains. C. elegans uses specific ascarosides, which are together known as the dauer pheromone, to trigger entry into the stress-resistant dauer larval stage. In addition, C. elegans uses specific ascarosides to control certain behaviors, including mating attraction, aggregation, and avoidance. Although in general the concentration of the ascarosides in the environment increases with population density, C. elegans can vary the types and amounts of ascarosides that it secretes depending on the culture conditions under which it has been grown and its developmental history. Here, we describe how to grow high-density worm cultures and the bacterial food for those cultures, as well as how to extract the culture medium to generate a crude pheromone extract. Then, we discuss how to analyze the types and amounts of ascarosides in that extract using mass spectrometry and NMR spectroscopy.
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Hygroscopic aerosol deposition in the human upper respiratory tract under various thermo-humidity conditions.
J Environ Sci Health A Tox Hazard Subst Environ Eng
PUBLISHED: 09-07-2013
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The deposition of hygroscopic aerosols is highly complex in nature, which results from a cumulative effect of dynamic particle growth and the real-time size-specific deposition mechanisms. The objective of this study is to evaluate hygroscopic effects on the particle growth, transport, and deposition of nasally inhaled aerosols across a range of 0.2-2.5 ?m in an adult image-based nose-throat model. Temperature and relative humidity fields were simulated using the LRN k-? turbulence model and species transport model under a spectrum of thermo-humidity conditions. Particle growth and transport were simulated using a well validated Lagrangian tracking model coupled with a user-defined hygroscopic growth module. Results of this study indicate that the saturation level and initial particle size are the two major factors that determine the particle growth rate (d/d0), while the effect of inhalation flow rate is found to be not significant. An empirical correlation of condensation growth of nasally inhaled hygroscopic aerosols in adults has been developed based on a variety of thermo-humidity inhalation conditions. Significant elevated nasal depositions of hygroscopic aerosols could be induced by condensation growth for both sub-micrometer and small micrometer particulates. In particular, the deposition of initially 2.5 ?m hygroscopic aerosols was observed to be 5-8 times that of inert particles under warm to hot saturated conditions. Results of this study have important implications in exposure assessment in hot humid environments, where much higher risks may be expected compared to normal conditions.
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Enzyme-responsive supramolecular nanovalves crafted by mesoporous silica nanoparticles and choline-sulfonatocalix[4]arene [2]pseudorotaxanes for controlled cargo release.
Chem. Commun. (Camb.)
PUBLISHED: 08-29-2013
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Mesoporous silica nanoparticles (MSNs) have been surface-functionalized with choline moieties encircled by sulfonatocalix[4]arenes. Two enzyme cleavable sites are incorporated in the stalks for specific enzymes to regulate the release of loaded cargos from MSNs. These gated materials show a clear enzymatic response and proven orthogonality.
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Solid and hollow pedicle screws affect the electrical resistance: A potential source of error with stimulus-evoked electromyography.
Indian J Orthop
PUBLISHED: 08-21-2013
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Although stimulus evoked electromyography (EMG) is commonly used to confirm the accuracy of pedicle screw placement. There are no studies to differentiate between solid screws and hollow screws to the electrical resistance of pedicle screws. We speculate that the electrical resistance of the solid and hollow pedicle screws may be different and then a potential source of error with stimulus-evoked EMG may happen.
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Dependence of the direct electron transfer activity and adsorption kinetics of cytochrome c on interfacial charge properties.
Analyst
PUBLISHED: 08-06-2013
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With the advantages of in situ analysis and high surface sensitivity, surface-enhanced infrared absorption spectroscopy in attenuated total reflection mode (ATR-SEIRAS) combined with electrochemical methods has been employed to examine the interfacial direct electron transfer activity and adsorption kinetics of cytochrome c (cyt c). This work presents data on cyt c adsorption onto negatively charged mercaptohexanoic acid (MHA) and positively charged 6-amino-1-hexanethiol (MHN) self-assembled monolayers (SAMs) on gold nanofilm surfaces. The adsorbed cyt c displays a higher apparent electron transfer rate constant (33.5 ± 2.4 s(-1)) and apparent binding rate constant (73.1 ± 5.2 M(-1) s(-1)) at the MHA SAMs surface than those on the MHN SAMs surface. The results demonstrate that the surface charge density determines the protein adsorption kinetics, while the surface charge character determines the conformation and orientation of proteins assembled which in turn affects the direct electron transfer activity.
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p38-Mediated phosphorylation of Eps15 endocytic adaptor protein.
FEBS Lett.
PUBLISHED: 07-30-2013
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Epidermal growth factor receptor pathway substrate 15 (Eps15) has been suggested to be involved in the endocytosis of cell surface receptors, including epidermal growth factor receptor (EGFR). Eps15 is phosphorylated at Tyr-849 upon stimulation with EGF during endocytic processes. In the present study, we found that stimulation of HeLa cells with EGF or TNF-? induced transient phosphorylation of Eps15 at Ser-796. Inhibition of p38 completely blocked phosphorylation and recombinant p38? directly phosphorylated the residue. These results demonstrate a novel stress kinase-mediated signaling pathway to Eps15 endocytic adapter protein.
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Thymosin ?4 Attenuates Early Diabetic Nephropathy in a Mouse Model of Type 2 Diabetes Mellitus.
Am J Ther
PUBLISHED: 07-13-2013
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The chronic inflammatory processes and endothelial dysfunction play important roles in the development of diabetic nephropathy (DN); the study aims to evaluate the effect of thymosin ?4 (T?4), which has apparent anti-inflammatory properties and is capable of improving endothelial dysfunction, in early DN in a mouse model of type 2 diabetes mellitus. KK Cg-Ay/J (KK) mice, aged 12-14 weeks, were divided into the following groups: KK control group that was treated with saline; KK T?4 group that was treated with T?4 100 ng/10 g of intraperitoneal injection once a day. Nondiabetic age-matched C57BL mice were used as additional normal control and also treated with T?4. The urinary albumin/creatinine ratio (ACR), plasma urea nitrogen and creatinine, body weight, fasting blood glucose and 2-hour blood glucose during oral glucose tolerance testing, blood hemoglobin A1c, cholesterol, and triglyceride were determined at baseline time and 12 weeks after T?4 treatment for phenotypic characterizations. The KK T?4 group had reduced the mean fasting blood glucose, 2-hour blood glucose during oral glucose tolerance testing, hemoglobin A1c, and triglyceride levels compared with that in the KK control group (P < 0.05). T?4 treatment markedly reduced ACR (KK T?4 = 328.54 ± 46.14 mg/g vs. KK control = 540.34 ± 50.31 mg/g, P < 0.05). T?4 also significantly ameliorated renal pathological changes of KK T?4 mice as compared with that in KK control mice. T?4 treatment did not affect glucose homeostasis and urinary ACR and glomeruli of C57BL mice. These data in a novel mouse model of DN suggest that T?4 may ameliorate renal damage. This peptide may be a novel potential alternative agent for treatment of DN.
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Scaling Laws at the Nano Size: The Effect of Particle Size and Shape on the Magnetism and Relaxivity of Iron Oxide Nanoparticle Contrast Agents.
J Mater Chem B Mater Biol Med
PUBLISHED: 07-03-2013
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The magnetic properties of iron oxide nanoparticles govern their relaxivities and efficacy as contrast agents for MRI. These properties are in turn determined by their composition, size and morphology. Herein we present a systematic study of the effect of particle size and shape of magnetite nanocrystals synthesized by thermal decompositions of iron salts on both their magnetism and their longitudinal and transverse relaxivities, r 1 and r 2, respectively. Faceted nanoparticles demonstrate superior magnetism and relaxivities than spherical nanoparticles of similar size. For faceted nanoparticles, but not for spherical ones, r 1 and r 2 further increase with increasing particle size up to a size of 18 nm. This observation is in accordance with increasing saturation magnetization for nanoparticles increasing in size up to 12 nm, above which a plateau is observed. The NMRD (Nuclear Magnetic Resonance Dispersion) profiles of MIONs (Magnetic Iron Oxide Nanoparticles) display an increase in longitudinal relaxivity with decreasing magnetic field strength with a plateau below 1 MHz. The transverse relaxivity shows no dependence on the magnetic field strength between 20 MHz and 500 MHz. These observations translate to phantom MR images: in T 1-weighted SWIFT (SWeep imaging with Fourier Transform) images MIONs have a positive contrast with little dependence on particle size, whereas in T 2-weighted gradient-echo images MIONs create a negative contrast which increases in magnitude with increasing particle size. Altogether, these results will enable the development of particulate MRI contrast agents with enhanced efficacy for biomedical and clinical applications.
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Growth of Nasal-Laryngeal Airways in Children and Their Implications in Breathing and Inhaled Aerosol Dynamics.
Respir Care
PUBLISHED: 07-02-2013
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The human respiratory airway undergoes dramatic growth during infancy and childhood, which induces significant variability in airflow pattern and particle depositions. However, deposition studies have typically focused on adult subjects, results of which may not be readily extrapolated to children.
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Accountable care organizations: benefits and barriers as perceived by Rural Health Clinic management.
Rural Remote Health
PUBLISHED: 06-28-2013
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Rural Health Clinics (RHCs) have served the primary healthcare needs of the medically underserved in US rural areas for more than 30 years. As a new model of healthcare delivery, the Accountable Care Organization (ACO) offers potential opportunities for addressing the healthcare needs of rural populations, yet little is known about how the ACO model will meet the needs of RHCs. This article reports on the results of a survey, focus groups, and phone interviews with RHC management personnel on the subject of benefits of and barriers to RHC participation in ACOs.
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Surgical management of the multiple-ligament injured knee: a case series from chongqing, china and review of published reports.
Orthop Surg
PUBLISHED: 06-09-2013
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The correct management of multiple-ligament injured knees (MLIKs) remains controversial. This study aimed to summarize the epidemiological features and short-term results of patients treated in our department.
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Comparison of early and late percutaneous endoscopic lumbar discectomy for lumbar disc herniation.
Acta Neurochir (Wien)
PUBLISHED: 05-20-2013
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The optimal timing for percutaneous endoscopic lumbar discectomy (PELD) in cases of lumbar disc herniation (LDH) is debatable. This retrospective study sought to determine which category of PELD surgical intervention time resulted in greater improvement in clinical outcomes.
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Mussel oligopeptides protect human fibroblasts from hydrogen peroxide (H2O2)-induced premature senescence.
Arch Gerontol Geriatr
PUBLISHED: 05-10-2013
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Mussel bioactive peptides have been viewed as mediators to maximize the high quality of life. In this study, the anti-aging activities of mussel oligopeptides were evaluated using H2O2-induced prematurely senescent MRC-5 fibroblasts. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry displayed that exposure to H2O2 led to the loss of cell viability and cell cycle arrest. In addition, H2O2 caused the elevation of senescence-associated-?-galactosidase (SA-?-gal) activity and formation of senescence-associated heterochromatin foci (SAHF). It was found that pretreatment with mussel oligopeptides could significantly attenuate these properties associated with cellular senescence. Mussel oligopeptides also led to the increase of glutathione (GSH) level and mitochondrial transmembrane potential (??m) recovery. In addition, mussel oligopeptides resulted in an improvement in transcriptional activity of peroxiredoxin 1 (Prx1), nicotinamide phosphoribosyltransferase (NAMPT) and sirtuin 1 (SIRT1). This study revealed that mussel oligopeptides could protect against cellular senescence induced by H2O2, and the effects were closely associated with redox cycle modulating and potentiating the SIRT1 pathway. These findings provide new insights into the beneficial role of mussel bioactive peptides on retarding senescence process.
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Ginsenoside Rg1 enhances the resistance of hematopoietic stem/progenitor cells to radiation-induced aging in mice.
Acta Pharmacol. Sin.
PUBLISHED: 05-05-2013
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Aim:To investigate the effects of ginsenoside Rg1 on the radiation-induced aging of hematopoietic stem/progenitor cells (HSC/HPCs) in mice and the underlying mechanisms.Methods:Male C57BL/6 mice were treated with ginsenoside Rg1 (20 mg·kg(-1)·d(-1), ip) or normal saline (NS) for 7 d, followed by exposure to 6.5 Gy X-ray total body irradiation. A sham-irradiated group was treated with NS but without irradiation. Sca-1(+) HSC/HPCs were isolated and purified from their bone marrow using MACS. DNA damage was detected on d 1. The changes of anti-oxidative activities, senescence-related markers senescence-associated ?-galactosidase (SA-?-gal) and mixed colony-forming unit (CFU-mix), P16(INK4a) and P21(Cip1/Waf1) expression on d 7, and cell cycle were examined on d 1, d 3, and d 7.Results:The irradiation caused dramatic reduction in the number of Sca-1(+) HSC/HPCs on d 1 and the number barely recovered until d 7 compared to the sham-irradiated group. The irradiation significantly decreased SOD activity, increased MDA contents and caused DNA damage in Sca-1(+) HSC/HPCs. Moreover, the irradiation significantly increased SA-?-gal staining, reduced CFU-mix forming, increased the expression of P16(INK4a) and P21(Cip1/Waf1) in the core positions of the cellular senescence signaling pathways and caused G1 phase arrest of Sca-1(+) HSC/HPCs. Administration of ginsenoside Rg1 caused small, but significant recovery in the number of Sca-1(+) HSC/HPCs on d 3 and d 7. Furthermore, ginsenoside Rg1 significantly attenuated all the irradiation-induced changes in Sca-1(+) HSC/HPCs, including oxidative stress reaction, DNA damage, senescence-related markers and cellular senescence signaling pathways and cell cycle, etc.Conclusion:Administration of ginsenoside Rg1 enhances the resistance of HSC/HPCs to ionizing radiation-induced senescence in mice by inhibiting the oxidative stress reaction, reducing DNA damage, and regulating the cell cycle.
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Reoperation after lumbar disc surgery in two hundred and seven patients.
Int Orthop
PUBLISHED: 04-23-2013
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The purpose of this study was to compare the causes and characteristics of reoperations after different primary operations for lumbar disc herniation (LDH).
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Learning curve for percutaneous endoscopic lumbar discectomy depending on the surgeons training level of minimally invasive spine surgery.
Clin Neurol Neurosurg
PUBLISHED: 04-16-2013
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To evaluate the differences of learning curve for PELD depending on the surgeon s training level of minimally invasive spine surgery.
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Nasal Deposition in Infants and Children.
J Aerosol Med Pulm Drug Deliv
PUBLISHED: 04-15-2013
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Abstract Background: The variability of particle deposition in infant and child nasal airways is significant due to the airway geometry and breathing rate. Estimation of particle deposition in the nasal airway of this age group is necessary, especially for inhalation drug delivery application. Previous studies on nasal aerosol deposition were focused mostly on adult. A few empirical equations were also developed to calculate nasal deposition in different age groups of children. However, those studies have their limitations. The aim of this study is to find a simple way to calculate the nasal aerosol deposition in all age groups. Methods: An in vitro test of micrometer particle deposition in nasal airways for three different ages of infants and children is conducted. An adult nasal replica is also studied as a comparison. Monodisperse oleic acid aerosols ranging in size between 2 and 28??m are delivered into the replica at the rest condition. This size range covers the deposition efficiency up to around 100%. This study also compares results from our previous deposition tests with a 5-year-old replica. Results: Nasal deposition of micrometer aerosols in small children and infants is higher than that in adults under equivalent breathing conditions, e.g., sitting awake in this study. Combining the data set of infants, children, and adults, we found the deposition in the nasal airway strongly depends on the particle size and pressure drop. The particle deposition can be calculated based on a single empirical equation in all age groups. The intersubject variability within the same age group was not addressed in this study. Conclusions: An empirical equation for all age groups is developed. From this equation, particle deposition efficiency in the nasal airway can best be estimated with input data of particle size and pressure drop of the airway.
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Senescence Effects of Angelica sinensis Polysaccharides on Human Acute Myelogenous Leukemia Stem and Progenitor Cells.
Asian Pac. J. Cancer Prev.
PUBLISHED: 04-09-2013
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Leukemia stem cells (LSCs) play important roles in leukemia initiation, progression and relapse, and thus represent a critical target for therapeutic intervention. Hence, it is extremely urgent to explore new therapeutic strategies directly targeting LSCs for acute myelogenous leukemia (AML) therapy. We show here that Angelica sinensis polysaccharide (ASP), a major active component in Dong quai (Chinese Angelica sinensis), effectively inhibited human AML CD34+CD38? cell proliferation in vitro culture in a dose-dependent manner while sparing normal hematopoietic stem and progenitor cells at physiologically achievable concentrations. Furthermore, ASP exerted cytotoxic effects on AML K562 cells, especially LSC-enriched CD34+CD38? cells. Colony formation assays further showed that ASP significantly suppressed the formation of colonies derived from AML CD34+CD38? cells but not those from normal CD34+CD38? cells. Examination of the underlying mechanisms revealed that ASP induced CD34+CD38? cell senescence, which was strongly associated with a series of characteristic events, including up-regulation of p53, p16, p21, and Rb genes and changes of related cell cycle regulation proteins P16, P21, cyclin E and CDK4, telomere end attrition as well as repression of telomerase activity. On the basis of these findings, we propose that ASP represents a potentially important agent for leukemia stem cell-targeted therapy.
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Disc herniation in the thoracolumbar junction treated by minimally invasive transforaminal interbody fusion surgery.
J Clin Neurosci
PUBLISHED: 04-09-2013
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Minimally invasive surgery-transforaminal lumbar interbody fusion (MIS-TLIF) has demonstrated efficacy in the treatment of lumbar degenerative diseases. Use of this procedure for thoracolumbar junction disc herniation remains challenging. Reports concerning MIS-TLIF at the thoracolumbar junction are rare. Thus, we performed a retrospective analysis of the clinical outcomes of 10 patients with thoracolumbar junction disc herniation treated by MIS-TLIF between December 2007 and October 2010. The purpose of this study was to investigate the efficacy and safety of MIS-TLIF for disc herniation in the thoracolumbar junction. Clinical and radiological data were collected and analyzed. Fusion levels included T12-L1 (two patients), L1-L2 (four patients) and L2-L3 (four patients). Clinical outcome was assessed using the Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI). The average follow-up period was 39.2months, with a minimum of 24months. The mean±standard error of the mean of the operative time, intraoperative blood loss, and x-ray exposure were 128±36minutes, 204±35mL, and 43±12seconds, respectively. The VAS for back and leg pain decreased significantly postoperatively from 6.4±2.7 to 1.5±0.6 (p<0.01), and from 7.1±2.4 to 1.3±0.4 (p<0.01) respectively, as did the ODI from 39.3±11.2 to 16.5±4.7 (p<0.01). Bone fusion was observed in eight patients. There were no other major complications at last follow-up. MIS-TIF is a safe and effective procedure for disc herniation in the thoracolumbar junction. Occurrence of non-union is relatively high compared to previous findings.
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Multiple-level noncontiguous spinal fractures: difference between the young and the elderly.
J Spinal Disord Tech
PUBLISHED: 03-21-2013
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We retrospectively reviewed the hospital records of all patients with multiple-level noncontiguous spinal fractures (MLNSF) at university-affiliated hospitals between January 2001 and May 2011 (n=213). The variables assessed included age, sex, spinal fracture mechanism, anatomic distribution, neurological deficit, and associated injury.
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Roles of microRNAs in prenatal chondrogenesis, postnatal chondrogenesis and cartilage-related diseases.
J. Cell. Mol. Med.
PUBLISHED: 03-19-2013
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Cartilage has limited repair and regeneration capacity, thus damage of cartilage often results in its dysfunction and even chronic diseases like osteoarthritis (OA). Chondrogenesis induced by tissue-engineering methods is essential to treating cartilage-related diseases. MicroRNAs (miRNAs) are a class of small non-coding single-stranded RNAs which exert their biological effects by binding to the target messenger RNAs (mRNAs), resulting in decay or translation suppression of target mRNAs. There are emerging evidence indicating that miRNAs may play important roles in regulating both prenatal and postnatal chondrogenesis. During embryonic skeletal development, prenatal chondrogenesis is thought to be a precondition for formation of cartilage in developing limbs. Plenty of studies on different types of stem cells have undoubtedly proven their capacity of differentiating into chondrocytes. MiRNAs are found to comprehensively modulate these processes by establishing an interaction network with target genes, transcription factors and cytokines et al. In addition, translational application of miRNA technology has also been explored. In this review, we focus on the up-dated progress on regulatory mechanisms of miRNAs in prenatal and postnatal chondrogenesis. In addition, several miRNA target genes and roles of miRNAs in cartilage-related diseases are also discussed. This will contribute to studies of chondrogenesis mechanisms and development of new treating methods.
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High-volumetric performance aligned nano-porous microwave exfoliated graphite oxide-based electrochemical capacitors.
Adv. Mater. Weinheim
PUBLISHED: 03-18-2013
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Ultra-high volumetric performance electrochemical double layer capacitors based on high density aligned nano-porous microwave exfoliated graphite oxide have been studied. Elimination of macro-, meso-, and larger micro-pores from electrodes and controlling the nano-morphology results in very high volumetric capacitance, energy, and power density values.
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Overexpression of ECRG4 enhances chemosensitivity to 5-fluorouracil in the human gastric cancer SGC-7901 cell line.
Tumour Biol.
PUBLISHED: 03-13-2013
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The aim of this study was to examine the effects of esophageal cancer-related gene 4 (ECRG4) expression levels on chemotherapeutic sensitivity of gastric cancer cells. A SGC-7901 cell system with tetracycline-inducible ECRG4 expression (SGC-7901/ECRG4) was successfully established. ECRG4 mRNA and protein expression levels were detected using quantitative reverse transcription polymerase chain reaction and Western blotting, respectively. Chemosensitivity to 5-fluorouracil (5-FU) was examined by cell proliferation assay and cell apoptosis assay. ECRG4 mRNA and protein expression levels were significantly upregulated in SGC-7901/ECRG4 cells induced with tetracycline. Compared with control cells, the growth inhibition rate of cells with ECRG4 overexpression was significantly increased when treated with 5-FU. Treatment with 5 ?mol/l 5-FU resulted in 15.2 % apoptotic cells, whereas such treatment after overexpression of ECRG4 resulted in 44.5 % apoptotic cells. In conclusion, overexpression of ECRG4 enhanced the chemosensitivity of gastric cancer SGC-7901 cells to 5-FU through induction of apoptosis.
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Host reaction to poly(2-hydroxyethyl methacrylate) scaffolds in a small spinal cord injury model.
J Mater Sci Mater Med
PUBLISHED: 03-11-2013
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Tissue engineered scaffolds and matrices have been investigated over the past decade for their potential in spinal cord repair. They provide a 3-D substrate that can be permissive for nerve regeneration yet have other roles including neuroprotection, altering the inflammatory cascade and mechanically stabilizing spinal cord tissue after injury. In this study we investigated very small lesions (approx. 0.25 ?L in volume) of the dorsal column into which a phase-separated poly(2-hydroxyethyl methacrylate) hydrogel scaffold is implanted. Using fluorescent immunohistochemistry to quantify glial scarring, the poly(2-hydroxyethyl methacrylate) scaffold group showed reduced intensity compared to lesion controls for GFAP and the chondroitin sulfate proteoglycan neurocan after 6 days. However, the scaffold and tissue was also pushed dorsally after 6 days while the scaffold was not integrated into the spinal cord after 28 days. Overall, this small-lesion spinal cord injury model provided information on the host tissue reaction of a TE scaffold while reducing animal discomfort and care.
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Inverse correlation between Thr-669 and constitutive tyrosine phosphorylation in the asymmetric epidermal growth factor receptor dimer conformation.
Cancer Sci.
PUBLISHED: 03-08-2013
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We have recently identified tumor necrosis factor (TNF)-?-induced phosphorylation of epidermal growth factor receptor (EGFR) at Thr-669 and Ser-1046/1047 via ERK and p38 pathways, respectively. In the present study, we investigated the roles of ligand-induced phosphorylation of serine and threonine residues in EGFR-overexpressing MDA-MB-468 breast cancer cells. Epidermal growth factor and heregulin, an ErbB3 ligand, induced the phosphorylation of Thr-669 and Ser-1046/1047. Inversely, constitutive tyrosine phosphorylation of the C-terminal domain, including Tyr-1068, was significantly downregulated on ligand stimulation. Inhibition of the ERK pathway by U0126 blocked ligand-induced Thr-669 phosphorylation as well as Tyr-1068 dephosphorylation. Downregulation of constitutive tyrosine phosphorylation of EGFR in HEK293 cells stably expressing the wild type was abolished by substitution of Thr-669 for Ala. In an asymmetric EGFR homodimer structure, one Thr-669 in the receiver kinase of the dimer was involved in downregulation. Similarly, Thr-669 in an EGFR-ErbB3 heterodimer also participated in tyrosine dephosphorylation. These results indicate that ERK-mediated Thr-669 phosphorylation suppresses constitutive tyrosine phosphosphorylation in the homo- and heterodimer asymmetric conformations of the EGFR.
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Human epidermal growth factor receptor-2 expression in primary and metastatic gastric cancer.
Int. J. Clin. Oncol.
PUBLISHED: 02-23-2013
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BACKGROUND: Amplification and overexpression of human epidermal growth factor receptor-2 (HER-2) has been shown in subgroups of gastric cancer, correlated to more aggressive disease and predictive for the treatment with HER-2 antibodies. In this study, we examined the prognostic value of HER-2 expression in primary gastric cancer and in associated lymph node metastases and confirmed the role of HER-2 in tumor angiogenesis by examining vascular endothelial growth factor (VEGF) expression. METHODS: Immunohistochemistry was used to detect HER-2 and VEGF expression in 110 gastric cancer specimens and associated lymph node metastases and in 96 specimens of normal gastric mucosa. RESULTS: The expression level of HER-2 in gastric tissues was significantly higher than in normal tissues (19.1 % vs. 8.3 %; P < 0.05). HER-2 overexpression was homogeneous in primary gastric cancer and metastatic lymph nodes (P = 0.607). There was a significant positive correlation of HER-2 expression and VEGF expression (P = 0.007). HER-2 overexpression in primary tumor correlated with lymph node metastasis, distant metastasis, and American Joint Committee on Cancer (AJCC) stage. Cox regression multivariate analyses confirmed that tumor size, histological grade, lymph node ratio, AJCC stage, chemotherapy, and HER-2 expression were all prognostic factors. Patients with HER-2 positivity in both primary and metastatic tissues (+/+) had the poorest survival (OS, 12.5 months; DFS, 11.0 months) (P < 0.01). CONCLUSIONS: HER-2 was significantly overexpressed in gastric cancer versus normal tissue and correlated with VEGF expression. HER-2 in tumor or lymph nodes was an independent negative prognostic factor.
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Mussel oligopeptides ameliorate cognition deficit and attenuate brain senescence in D-galactose-induced aging mice.
Food Chem. Toxicol.
PUBLISHED: 02-20-2013
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Dietary supplementation exerts beneficial effects in reducing incidence of chronic neurodegenerative diseases. The purpose of this study was to examine protective effects of mussel (Mytilus edulis) oligopeptides supplementation on brain function in D-galactose induced aging mice. Sixty female 8-month-old mice were randomly divided into five groups: vehicle control, D-galactose, and D-galactose combined with 200, 500, 1000 mg/kg mussel oligopeptides. The results showed that mussel oligopeptides could improve cognitive learning and memory ability and protect the hippocampal neurons. In addition, GSH, SOD and GSH-pX activities were increased and MDA level was significantly decreased in mice fed with mussel oligopeptides. It was also found that mussel oligopeptides supplementation prevented D-galactose-induced elevations of iNOS activity and NO production and lactate acid levels in brain. Moreover, PI3K and Akt genes were up-regulated by mussel oligopeptides supplementation. These findings suggest that mussel oligopeptides are able to enhance exercise capacity and protect against oxidative damage caused by D-galactose in aging model mice through regulating oxidation metabolism and PI3K/Akt/NOS signal pathway. Therefore, mussel oligopeptides are good materials for future development of healthcare products to combat age-related brain dysfunction and to improve healthy life span.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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