21 research outputs found

    Minimal information for studies of extracellular vesicles 2018 (MISEV2018):a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

    Get PDF
    The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points

    Dynamic Scapular Movement Analysis: Is It Feasible and Reliable in Stroke Patients during Arm Elevation?

    Get PDF
    Knowledge of three-dimensional scapular movements is essential to understand post-stroke shoulder pain. The goal of the present work is to determine the feasibility and the within and between session reliability of a movement protocol for three-dimensional scapular movement analysis in stroke patients with mild to moderate impairment, using an optoelectronic measurement system. Scapular kinematics of 10 stroke patients and 10 healthy controls was recorded on two occasions during active anteflexion and abduction from 0° to 60° and from 0° to 120°. All tasks were executed unilaterally and bilaterally. The protocol’s feasibility was first assessed, followed by within and between session reliability of scapular total range of motion (ROM), joint angles at start position and of angular waveforms. Additionally, measurement errors were calculated for all parameters. Results indicated that the protocol was generally feasible for this group of patients and assessors. Within session reliability was very good for all tasks. Between sessions, scapular angles at start position were measured reliably for most tasks, while scapular ROM was more reliable during the 120° tasks. In general, scapular angles showed higher reliability during anteflexion compared to abduction, especially for protraction. Scapular lateral rotations resulted in smallest measurement errors. This study indicates that scapular kinematics can be measured reliably and with precision within one measurement session. In case of multiple test sessions, further methodological optimization is required for this protocol to be suitable for clinical decision-making and evaluation of treatment efficacy.ISSN:1932-620

    Characteristics of neuromuscular control of the scapula after stroke: a first exploration

    Get PDF
    This study aimed to characterize scapular muscle timing in stroke patients with and without shoulder pain. Muscle activity of upper trapezius, lower trapezius, serratus anterior, infraspinatus, and anterior deltoid (AD) was measured (Delsys Trigno surface EMG system, USA) in 14 healthy controls (dominant side) and 30 stroke patients (hemiplegic side) of whom 10 had impingement-like shoulder pain. Participants performed 45° and full range anteflexion, in two load conditions. The impact of group, anteflexion height, load condition, and muscle was assessed for onset and offset of the different muscles relative to the onset and offset of AD, using a 3 (group) × 2 (height) × 2 (load) × 4 (muscle) mixed model design. Recruitment patterns were additionally described. Across all load conditions and groups, serratus anterior had a significantly earlier onset and, together with lower trapezius, a significantly later offset in 45° compared to full range anteflexion tasks (p < 0.001). In stroke patients without pain, lower trapezius had furthermore a significantly earlier onset in comparison to stroke patients with shoulder pain (all tasks, p = 0.04). Serratus anterior also showed a significantly earlier offset in stroke patients with shoulder pain in comparison to controls (p = 0.01) and stroke patients without pain (p < 0.001). Analysis of muscle recruitment patterns indicated that for full range tasks, stroke patients without pain used early and prolonged activity of infraspinatus. In stroke patients with shoulder pain, recruitment patterns were characterized by delayed activation and early inactivity of serratus anterior. These timing results can serve as a reference frame for scapular muscle timing post-stroke, and when designing upper limb treatment protocols and clinical guidelines for shoulder pain after stroke

    The effect of presentation level on spectrotemporal modulation detection

    No full text
    The understanding of speech in noise relies (at least partially) on spectrotemporal modulation sensitivity. This sensitivity can be measured by spectral ripple tests, which can be administered at different presentation levels. However, it is not known how presentation level affects spectrotemporal modulation thresholds. In this work, we present behavioral data for normal-hearing adults which show that at higher ripple densities (2 and 4 ripples/oct), increasing presentation level led to worse discrimination thresholds. Results of a computational model suggested that the higher thresholds could be explained by a worsening of the spectrotemporal representation in the auditory nerve due to broadening of cochlear filters and neural activity saturation. Our results demonstrate the importance of taking presentation level into account when administering spectrotemporal modulation detection tests.status: publishe

    Ce(III)-based frameworks : from 1D chain to 3D porous metal-organic framework

    No full text
    The reaction of pyridine-2,4-dicarboxylic acid (2,4-H-2 pydc) with Ce(NO3)(3)center dot 6H(2)O, by applying only minor changes to the reaction conditions, generated a series of new one-, two-, and three-dimensional (1D, 2D, and 3D) coordination polymers, namely, [Ce(pydc)(Hpydc)-(H2O)(4)](n) (1), [Ce(pydc)(Hpydc)(H2O)(2)](n), (2), and {[Ce-3(pydc)(4)-(H2O)(2)NO3]center dot 4H(2)O}(n) (3). The ancillary ligand interaction as well as the reaction conditions determine the specific coordination modes for the Hpydc(-) and pydc(2-) ligands and, in turn, discriminate between 1D, 2D, and 3D frameworks. Characterization of the prepared materials was performed using single-crystal and powder X-ray diffraction analysis, Fourier transform infrared spectroscopy, CHN elemental analysis, thermogravimetric analysis, and nitrogen adsorption/desorption techniques. Compound 1 consists of 1D chains, that compose of Ce3+ ions bridged by Hpydc(-) and pydc(2-) ligands, which further link via noncovalent interactions to form a 3D supramolecular architecture. Compound 2 assembles into 2D sheets with 1D channels. Similarly, via hydrogen-bonding interactions between two adjacent sheets, the 2D layers are further stacked into the final 3D supramolecular structure. Compound 3 is a 3D metal-organic framework (MOF), showing 1D helical channels. The progressive skeletal variation from the 1D chains (1) to 2D sheets (2) and 3D framework (3) is attributed to the flexibility of both the Ce(III) coordination sphere and coordination modes of the Hpydc(-) and pydc(2-) ligands under different reaction conditions. The three compounds illustrate how the tuning of the coordination geometry of Ce(III) translates into different dimensionality, which is readily influenced by reaction temperature and ancillary ligand presence. Moreover, the porosity of MOF 3 was confirmed by N-2 and CO2 gas adsorption/desorption. Finally, the catalytic activity of MOF 3 was examined in acetalization reactions in a series of aromatic aldehydes with methanol

    Within and between session reliability of angular waveforms.

    No full text
    <p>CMCs in healthy controls (A) and CMCs in stroke patients (B); FL: anteflexion; AB: abduction; BFL: bilateral anteflexion; BAB: bilateral abduction; No symbol is shown in case of calculation errors.</p

    Within session mean, standard deviation (SD) and standard error of measurement (SEM) for scapular range of motion (ROM).

    No full text
    <p>Mean, SD and SEM are presented in degrees; %SEM represents the percentage SEM with respect to the mean; %SEMs lower than 15% are marked in bold.</p

    Between session mean, standard deviation (SD) and standard error of measurement (SEM) for scapular range of motion (ROM).

    No full text
    <p>Mean, SD and SEM are presented in degrees; %SEM represents the percentage SEM with respect to the mean; %SEMs lower than 15% are marked in bold.</p

    Participants’ characteristics.

    No full text
    *<p>One patient had an addition lesion in the basal ganglia;</p>**<p>Upper extremity motor section; NA: not applicable.</p

    Within and between session reliability of parameters of interest.

    No full text
    <p>ICCs of range of motion in healthy controls (A), ICCs of range of motion in stroke patients (B) and ICCs of start position in healthy controls and stroke patients (C); FL: anteflexion; AB: abduction; BFL: bilateral anteflexion; BAB: bilateral abduction; No symbol is shown in case of calculation errors.</p
    corecore