2,420 research outputs found

    Infrapatellar fat pad adipose-derived stem cells co-cultured with articular chondrocytes from osteoarthritis patients exhibit increased chondrogenic gene expression.

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    AIM: The variable results in clinical trials of adipose tissue-derived stem cells (ASCs) for chondral defects may be due to the different ex vivo culture conditions of the ASCs which are implanted to treat the lesions. We sought to determine the optimal in vitro chondrocyte co-culture condition that promotes infrapatellar fat pad-derived (IFPD) ASC chondrogenic gene expression in a novel co-culture combination. METHODS: In our study, we utilized an in vitro autologous co-culture of IFPD ASCs and articular chondrocytes derived from Kellgren-Lawrence Grade III/IV osteoarthritic human knee joints at ASC-to-chondrocyte seeding log ratios of 1:1, 10:1, and 100:1. Gene expression following in vitro co-culture was quantified by RT-qPCR with a panel comprising COL1A1, COL2A1, COL10A1, L-SOX5, SOX6, SOX9, ACAN, HSPG2, and COMP for chondrogenic gene expression. RESULTS: The chondrogenic gene expression profiles from co-cultures were greater than would be expected from an expression profile modeled from chondrocyte and ASC-only monocultures. Additionally, chondrogenic gene expression decreased with increasing ASC-to-chondrocyte seeding ratios. CONCLUSIONS: These findings provide insight into the mechanisms underlying clinical ASC therapies and signifies that IFPD ASCs pre-conditioned by chondrocyte co-culture may have improved chondrogenic potential for cartilage repair. This model can help further understand IFPD ASCs in chondral and osteochondral repair and the chondrogenic pathways involved. Video Abstract

    Spin-Orbit-Induced Orbital Excitations in Sr2RuO4 and Ca2RuO4: A Resonant Inelastic X-ray Scattering Study

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    High-resolution resonant inelastic X-ray scattering (RIXS) at the oxygen K-edge has been used to study the orbital excitations of Ca2RuO4 and Sr2RuO4. In combination with linear dichroism X-ray absorption spectroscopy, the ruthenium 4d-orbital occupation and excitations were probed through their hybridization with the oxygen p-orbitals. These results are described within a minimal model, taking into account crystal field splitting and a spin-orbit coupling \lambda_{so}=200~meV. The effects of spin-orbit interaction on the electronic structure and implications for the Mott and superconducting ground states of (Ca,Sr)2RuO4 are discussed.Comment: accepted in PRB 201

    Rare earth contributions to the X-ray magnetic circular dichroism at the Co K edge in rare earth-cobalt compounds investigated by multiple-scattering calculations

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    The X-ray magnetic circular dichroism (XMCD) has been measured at the Co K edge in Co-hcp and R-Co compounds (R=La, Tb, Dy). The structure of the experimental XMCD spectra in the near-edge region has been observed to be highly sensitive to the magnetic environment of the absorbing site. Calculations of the XMCD have been carried out at the Co K edge in Co metal, LaCo5_5 and TbCo5_5 within the multiple-scattering framework including the spin-orbit coupling. In the three systems, the XMCD spectra in the near-edge region are well reproduced. The possibility to separate and quantitatively estimate the local effects from those due to the neighboring atoms in the XMCD cross section makes possible a more physical understanding of the spectra. The present results emphasize the major role played by the dd states of the Tb ions in the XMCD spectrum at the Co K edge in the TbCo5_5 compound.Comment: 34 pages, revtex, 10 eps figures included with epsf, after referee revie

    Magnetic topology of active regions and coronal holes: implications for coronal outflows and the solar wind

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    During 2-18 January 2008 a pair of low-latitude opposite-polarity coronal holes (CHs) were observed on the Sun with two active regions (ARs) and the heliospheric plasma sheet located between them. We use the Hinode/EUV Imaging Spectrometer (EIS) to locate AR-related outflows and measure their velocities. Solar-Terrestrial Relations Observatory (STEREO) imaging is also employed, as are the Advanced Composition Explorer (ACE) in-situ observations, to assess the resulting impacts on the solar wind (SW) properties. Magnetic-field extrapolations of the two ARs confirm that AR plasma outflows observed with EIS are co-spatial with quasi-separatrix layer locations, including the separatrix of a null point. Global potential-field source-surface modeling indicates that field lines in the vicinity of the null point extend up to the source surface, enabling a part of the EIS plasma upflows access to the SW. We find that similar upflow properties are also observed within closed-field regions that do not reach the source surface. We conclude that some of plasma upflows observed with EIS remain confined along closed coronal loops, but that a fraction of the plasma may be released into the slow SW. This suggests that ARs bordering coronal holes can contribute to the slow SW. Analyzing the in-situ data, we propose that the type of slow SW present depends on whether the AR is fully or partially enclosed by an overlying streamer. © 2012 Springer Science+Business Media B.V

    Quantum oscillations in quasi-one-dimensional metals with spin-density-wave ground states

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    We consider the magnetoresistance oscillation phenomena in the Bechgaard salts (TMTSF)(2)X, where X = ClO4, PF6, and AsF6 in pulsed magnetic fields to 51 T. Of particular importance is the observation of a new magnetoresistance oscillation for X = ClO4 in its quenched state. In the absence of any Fermi-surface reconstruction due to anion order at low temperatures, all three materials exhibit nonmonotonic temperature dependence of the oscillation amplitude in the spin-density-wave (SDW) state. We discuss a model where, below a characteristic temperature T* within the SDW state, a magnetic breakdown gap opens. [S0163-1829(99)00904-2]

    SILAC-based phosphoproteomics reveals an inhibitory role of KSR1 in p53 transcriptional activity via modulation of DBC1

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    BACKGROUND We have previously identified kinase suppressor of ras-1 (KSR1) as a potential regulatory gene in breast cancer. KSR1, originally described as a novel protein kinase, has a role in activation of mitogen-activated protein kinases. Emerging evidence has shown that KSR1 may have dual functions as an active kinase as well as a scaffold facilitating multiprotein complex assembly. Although efforts have been made to study the role of KSR1 in certain tumour types, its involvement in breast cancer remains unknown. METHODS A quantitative mass spectrometry analysis using stable isotope labelling of amino acids in cell culture (SILAC) was implemented to identify KSR1-regulated phosphoproteins in breast cancer. In vitro luciferase assays, co-immunoprecipitation as well as western blotting experiments were performed to further study the function of KSR1 in breast cancer. RESULTS Of significance, proteomic analysis reveals that KSR1 overexpression decreases deleted in breast cancer-1 (DBC1) phosphorylation. Furthermore, we show that KSR1 decreases the transcriptional activity of p53 by reducing the phosphorylation of DBC1, which leads to a reduced interaction of DBC1 with sirtuin-1 (SIRT1); this in turn enables SIRT1 to deacetylate p53. CONCLUSION Our findings integrate KSR1 into a network involving DBC1 and SIRT1, which results in the regulation of p53 acetylation and its transcriptional activity

    Urinary Extracellular Domain of Neurotrophin Receptor p75 as a Biomarker for Amyotrophic Lateral Sclerosis in a Chinese cohort

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    To comprehensively assess whether p75ECD in urine could be a candidate biomarker for ALS evaluation. Urine samples were collected from 101 ALS patients, 108 patients with other neurological disease (OND) and 97 healthy controls. 61 ALS patients were followed up with clinical data including ALSFRS-r every 6 to 12 months, 23 ALS patients died and 17 ALS patients lost touch during follow up period. Enzyme-linked immunoassay was employed to determine urine p75ECD concentration. The ALSFRS-r was employed to assess the severity of ALS. The concentration of p75ECD in ALS was significantly higher than that of OND and CTRL (p < 0.001). Additionally, urine p75ECD concentrations in ALS-definite grade patients were significantly higher than that in ALS-probable grade and ALS-possible grade patients (p < 0.001). Higher urine p75ECD concentrations were correlated with increased clinical stage (p = 0.0309); urine p75ECD concentrations and ALSFRS-r were negatively correlated (p = 0.022); and urine p75ECD concentration in the fast-progressing ALS group was significantly higher than that in slow-progression (p = 0.0026). Our finding indicates that urine p75ECD concentration provides additional evidence for patients with clinically suspected ALS, and can be employed to evaluate ALS-severity

    Protocol for Physiotherapy OR Tvt Randomised Efficacy Trial (PORTRET): a multicentre randomised controlled trial to assess the cost-effectiveness of the tension free vaginal tape versus pelvic floor muscle training in women with symptomatic moderate to severe stress urinary incontinence

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    <p>Abstract</p> <p>Background</p> <p>Stress urinary incontinence is a common condition affecting approximately 20% of adult women causing substantial individual (quality of life) and economic (119 million Euro/year spent on incontinence pads in the Netherlands) burden. Pelvic floor muscle training (PFMT) is regarded as first line treatment, but only 15-25% of women will be completely cured. Approximately 65% will report that their condition improved, but long term adherence to treatment is problematic. In addition, at longer term (2-15 years) follow-up 30-50% of patients will end up having surgery. From 1996 a minimal invasive surgical procedure, the Tension-free Vaginal Tape (TVT) has rapidly become the gold standard in surgical treatment of stress urinary incontinence. With TVT 65-95% of women are cured. However, approximately 3-6% of women will develop symptoms of an overactive bladder, resulting in reduced quality of life. Because of its efficacy the TVT appears to be preferable over PFMT but both treatments and their costs have not been compared head-to-head in a randomised clinical trial.</p> <p>Methods/Design</p> <p>A multi-centre randomised controlled trial will be performed for women between 35 - 80 years old with moderate to severe, predominantly stress, urinary incontinence, who have not received specialised PFMT or previous anti-incontinence surgery. Women will be assigned to either PFMT by a specialised physiotherapist for a standard of 9-18 session in a period of 6 months, or TVT(O) surgery. The main endpoint of the study is the subjective improvement of urinary incontinence. As secondary outcome the objective cure will be assessed from history and clinical parameters. Subjective improvement in quality of life will be measured by generic (EQ-5D) and disease-specific (Urinary Distress Inventory and Incontinence Impact Questionnaire) quality of life instruments. The economical endpoint is short term (1 year) incremental cost-effectiveness in terms of costs per additional year free of urinary incontinence and costs per Quality Adjusted Life Years (QALY) gained. Finally, treatment strategy and patient characteristics will be combined in a prediction model, to allow for individual treatment decisions in future patients. Four hundred female patients will be recruited from over 30 hospitals in the Netherlands</p> <p>Trial registration</p> <p>Nederlands trial register: NTR 1248</p

    How Geography Curricula Tackle Global Issues

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    The late Doreen Massey recently urged teachers to ‘take on the world’ (Massey, 2014). Though we may see the everyday world as a mosaic of different places, nations or regions defined by their boundaries, a global understanding brings different perspectives: of flows and networks and interdependencies. If we take this seriously - if we do take on the world - then young people need ideas in order to provide new ways of seeing and thinking. Geography in this sense is a disciplinary resource that provides access to a particular form of powerful knowledge: in short, the means to be able to ‘think geographically’. This chapter opens up and presents this argument. In the first part we provide a platform in the form of analysis of geography curricula from three countries, identifying both the potentials and the challenges that teachers face. Where is ‘the global’, we ask, and in what ways do formal curriculum documents inspire or constrain us from ‘taking on the world’? The second part seeks to develop a disciplinary view of the school subject, appealing to the sometimes beguiling notion of powerful knowledge. We end by introducing a capabilities approach to thinking about the school subject which demonstrates the responsibility that inevitably falls to well-prepared teachers to enact the curriculum
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