Silica nanoparticles surface-modified with thiacalixarenes selectively adsorb oligonucleotides and proteins

We prepared silica nanospheres 360 nm in diameter surface-modified with p-tert-butylthiacalix[4]arenes containing amine, carboxyl, and guanidinium groups. We found that these silica nanoparticles selectively adsorb model oligonucleotides and proteins. The particles modified with the macrocycle containing guanidinium fragments selectively adsorbed long-chain oligonucleotides and those modified with the macrocycle containing amine groups adsorbed BSA and hemoglobin with pH-dependent selectivity. We compared this behavior with that of silica nanoparticles carrying amine and carboxyl groups, and concluded that both electrostatic interactions and specific binding are responsible for the observed selectivity. © 2013 Springer Science+Business Media Dordrecht

Silica colloidal membranes with enantioselective permeability

Robust mesoporous membranes composed of silica spheres were surface-modified with chiral selector moieties, including small molecules, macrocycles, and polymers. Diffusion rates of enantiomers of a chiral dye through the resulting asymmetrically modified colloidal membranes were measured and the corresponding permselectivities were calculated. The membranes showed enantioselectivities in the range of 1.2-1.8, which were not significantly affected by the structure of the surface-immobilized chiral electors. This selectivity is on par with most reported polymer-based solid membranes and bulk liquid membranes. The enantioselectivity results from the surface-facilitated mechanism of transport of enantiomers through the mesopores. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

A MATEMÁTICA DO PLANETA É A MATEMATINETA

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Footprint preparation with nanofractures in a supraspinatus repair cuts in half the retear rate at 1-year follow-up. A randomized controlled trial

Purpose: To evaluate if adding nanofractures to the footprint of a supraspinatus tear repair would have any effect in the outcomes at one-year follow-up. Methods: Multicentric, triple-blinded, randomized trial with 12-months follow-up. Subjects with isolated symptomatic reparable supraspinatus tears smaller than 3 cm and without grade 4 fatty infiltration were included. These were randomized to two groups: In the Control group an arthroscopic supraspinatus repair was performed; in the Nanofracture group the footprint was additionally prepared with nanofractures (1 mm wide, 9 mm deep microfractures). Clinical evaluation was done with Constant score, EQ-5D-3L, and Brief Pain Inventory. The primary outcome was the retear rate in MRI at 12-months follow-up. Secondary outcomes were: characteristics of the retear (at the footprint or at the musculotendinous junction) and clinical outcomes. Results: Seventy-one subjects were randomized. Two were lost to follow-up, leaving 69 participants available for assessment at 12-months follow-up (33 in the Control group and 36 in the Nanofracture Group). The Nanofracture group had lower retear rates than the Control group (7/36 [19.4%] vs 14/33 [42.4%], differences significant, p = 0.038). Retear rates at the musculotendinous junction were similar but the Nanofracture group had better tendon healing rates to the bone (34/36 [94.4%] vs. 24/33 [66.71%], p = 0.014). Clinically both groups had significant improvements, but no differences were found between groups. Conclusion: Adding nanofractures at the footprint during an isolated supraspinatus repair lowers in half the retear rate at 12-months follow-up. This is due to improved healing at the footprint

Challenges associated with biomarker-based classification systems for Alzheimer's disease

Altres ajuts: This work was also supported by research grants from the Carlos III Institute of Health, Spain and the CIBERNED program (Program 1, Alzheimer Disease to Alberto Lleó and SIGNAL study, www.signalstudy.es), partly funded by Fondo Europeo de Desarrollo Regional (FEDER), Unión Europea, "Una manera de hacer Europa". This work has also been supported by a "Marató TV3" grant (20141210 to Juan Fortea and 044412 to Rafael Blesa) and by Generalitat de Catalunya and a grant from the Fundació Bancaria La Caixa to Rafael Blesa. I. Illán-Gala is supported by the i-PFIS grant from the FIS, Instituto de Salud Carlos III and the Rio Hortega grant (CM17/00074) from "Acción estratégica en Salud 2013-2016" and the European Social Fund. USPHS NIH grants awarded to M.J.d.L. include: AG13616, AG022374, AG12101, and AG057570.We aimed to evaluate the consistency of the A/T/N classification system. We included healthy controls, mild cognitive impairment, and dementia patients from Alzheimer's disease Neuroimaging Initiative. We assessed subject classification consistency with different biomarker combinations and the agreement and correlation between biomarkers. Subject classification discordance ranged from 12.2% to 44.5% in the whole sample; 17.3%-46.4% in healthy controls; 11.9%-46.5% in mild cognitive impairment, and 1%-35.7% in dementia patients. Amyloid, but not neurodegeneration biomarkers, showed good agreement both in the whole sample and in the clinical subgroups. Amyloid biomarkers were correlated in the whole sample, but not along the Alzheimer's disease continuum (as defined by a positive amyloid positron emission tomography). Neurodegeneration biomarkers were poorly correlated both in the whole sample and along the Alzheimer's disease continuum. The relationship between biomarkers was stage-dependent. Our findings suggest that the current A/T/N classification system does not achieve the required consistency to be used in the clinical setting

Probing the physics of the solar atmosphere with the Multi-slit Solar Explorer (MUSE). I. Coronal heating

Funding: I.D.M. has received support from the UK Science and Technology Facilities Council (Consolidated grant ST/K000950/1), the European Union Horizon 2020 research and innovation program (grant agreement No. 647214), and the Research Council of Norway through its Centres of Excellence scheme, project number 262622.The Multi-slit Solar Explorer (MUSE) is a proposed mission composed of a multislit extreme ultraviolet (EUV) spectrograph (in three spectral bands around 171 Å, 284 Å, and 108 Å) and an EUV context imager (in two passbands around 195 Å and 304 Å). MUSE will provide unprecedented spectral and imaging diagnostics of the solar corona at high spatial (≤0.″5) and temporal resolution (down to ∼0.5 s for sit-and-stare observations), thanks to its innovative multislit design. By obtaining spectra in four bright EUV lines (Fe ix 171 Å, Fe xv 284 Å, Fe xix–Fe xxi 108 Å) covering a wide range of transition regions and coronal temperatures along 37 slits simultaneously, MUSE will, for the first time, “freeze” (at a cadence as short as 10 s) with a spectroscopic raster the evolution of the dynamic coronal plasma over a wide range of scales: from the spatial scales on which energy is released (≤0.″5) to the large-scale (∼170″ × 170″) atmospheric response. We use numerical modeling to showcase how MUSE will constrain the properties of the solar atmosphere on spatiotemporal scales (≤0.″5, ≤20 s) and the large field of view on which state-of-the-art models of the physical processes that drive coronal heating, flares, and coronal mass ejections (CMEs) make distinguishing and testable predictions. We describe the synergy between MUSE, the single-slit, high-resolution Solar-C EUVST spectrograph, and ground-based observatories (DKIST and others), and the critical role MUSE plays because of the multiscale nature of the physical processes involved. In this first paper, we focus on coronal heating mechanisms. An accompanying paper focuses on flares and CMEs.Publisher PDFPeer reviewe