Do quantitative and qualitative shear wave elastography have a role in evaluating musculoskeletal soft tissue masses?

Objectives: To determine if quantitative and qualitative shear wave elastography have roles in evaluating musculoskeletal masses. Methods: 105 consecutive patients, prospectively referred for biopsy within a specialist sarcoma centre, underwent B-mode, quantitative (m/s) and qualitative (colour map) shear wave elastography. Reference was histology from subsequent biopsy or excision where possible. Statistical modelling was performed to test elastography data and/or B-mode imaging in predicting malignancy. Results: Of 105 masses, 39 were malignant and 6 had no histology but benign characteristics at 12 months. Radiologist agreement for B-mode and elastography was moderate to excellent Kw 0.52-0.64; PABAKw 0.85-0.90). B-Mode imaging had 78.8% specificity, 76.9% sensitivity for malignancy. Quantitatively, adjusting for age, B-mode and lesion volume there was no statistically significant association between longitudinal velocity and malignancy (OR [95% CI] 0.40[0.10, 1.60], p=0.193), but some evidence that higher transverse velocity was associated with decreased odds of malignancy (0.28[0.06, 1.28], p=0.101). Qualitatively malignant masses tended to be towards the blue spectrum (lower velocities); 39.5% (17/43) of predominantly blue masses were malignant, compared to 14.3% (1/7) of red lesions. Conclusions: Quantitatively and qualitatively there is no statistically significant association between shear wave velocity and malignancy. There is no clear additional role to B-mode imaging currently. Key Points: • Correlation between shear wave velocity and soft tissue malignancy was statistically insignificant• B-mode ultrasound is 76.9 % sensitive and 78.8 % specific• Statistical models show elastography does not significantly add to lesion assessmen

Reproducibility of shear wave elastography measuresof the Achilles tendon.

OBJECTIVE To assess the reproducibility of shear wave elastography (SWE) measures in the Achilles tendon (AT) in vivo. MATERIALS AND METHODS Shear wave velocity (SWV) of 14 healthy volunteers [7 males, 7 females; mean age 26.5 ± 3.8 years, mean height 171.6 ± 10.9 cm, mean Victorian Institute of Sports Assessment Achilles questionnaire (VISA-A) score 99.4 ± 1.2] was measured with the foot relaxed and fixed at 90°. Data were collected over five consecutive measures and 5 consecutive days. RESULTS Mean SWV values ranged from 7.91 m/s-9.56 m/s ± 0.27-0.50 m/s. Coefficient of variation (CV), correlations and intra-class correlation coefficient (ICC) scores ranged from 2.9%-6.3%, 0.4-0.7 and 0.54-0.85 respectively. No significant differences were noted for longitudinal or transverse data with respect to protocol or time and no significant differences were noted for foot position in transverse data. Significant differences in SWV values were noted between foot positions for longitudinal scanning (p = <0.05), with a relaxed foot position providing SWV values on average 0.47 m/s faster than a fixed position. Increased reproducibility was obtained with the foot relaxed. ICC between operators was 0.70 for transverse and 0.80 for longitudinal scanning. CONCLUSIONS Reproducible SWE measures were obtained over a 1-h period as well as a period of 5 consecutive days with more reliable measures obtained from a longitudinal plane using a relaxed foot position. SWE also has a high level of agreement between operators making SWE a reproducible technique for quantitatively assessing the mechanical properties of the human AT in vivo

Differential Modulation of Beta-Adrenergic Receptor Signaling by Trace Amine-Associated Receptor 1 Agonists

Trace amine-associated receptors (TAAR) are rhodopsin-like G-protein-coupled receptors (GPCR). TAAR are involved in modulation of neuronal, cardiac and vascular functions and they are potentially linked with neurological disorders like schizophrenia and Parkinson's disease. Subtype TAAR1, the best characterized TAAR so far, is promiscuous for a wide set of ligands and is activated by trace amines tyramine (TYR), phenylethylamine (PEA), octopamine (OA), but also by thyronamines, dopamine, and psycho-active drugs. Unfortunately, effects of trace amines on signaling of the two homologous β-adrenergic receptors 1 (ADRB1) and 2 (ADRB2) have not been clarified yet in detail. We, therefore, tested TAAR1 agonists TYR, PEA and OA regarding their effects on ADRB1/2 signaling by co-stimulation studies. Surprisingly, trace amines TYR and PEA are partial allosteric antagonists at ADRB1/2, whereas OA is a partial orthosteric ADRB2-antagonist and ADRB1-agonist. To specify molecular reasons for TAAR1 ligand promiscuity and for observed differences in signaling effects on particular aminergic receptors we compared TAAR, tyramine (TAR) octopamine (OAR), ADRB1/2 and dopamine receptors at the structural level. We found especially for TAAR1 that the remarkable ligand promiscuity is likely based on high amino acid similarity in the ligand-binding region compared with further aminergic receptors. On the other hand few TAAR specific properties in the ligand-binding site might determine differences in ligand-induced effects compared to ADRB1/2. Taken together, this study points to molecular details of TAAR1-ligand promiscuity and identified specific trace amines as allosteric or orthosteric ligands of particular β-adrenergic receptor subtypes

Properties of the Pb(Mg1/3Nb2/3)O3 Ceramics Prepared by Using Two Different Mg Precursors

Pb(Mg1/3Nb2/3)O3 ceramics prepared via columbite method by using two types of Mg precursors, i.e. MgO and (MgCO3)4\ub7Mg(OH)2\ub74H2O exhibit high crystallinity and high densification after sintering at 1200\ub0C. Higher amounts of pyrochlore phases were detected in the PMN sample obtained by using (MgCO3)4\ub7 Mg(OH)2.4H2O as precursor. This compositional difference, determines, for all frequencies, a shift of 3c 50 K of the temperature corresponding to the permittivity maximum Tm for the sample derived from (MgCO3)4\ub7Mg(OH)2\ub74H2O. From this reason, better dielectric properties were obtained at room temperature for this PMN sample, although a higher dielectric permittivity at Tm was obtained for the sample derived from MgO precursor

Raman investigation and functional characterization of (Pb(0.8)La(0.2))(Mg(0.4)Nb(0.6))O(3) ceramics prepared by the columbite method

(Pb(0.8)La(0.2))(Mg(0.4)Nb(0.6))O(3) relaxor ceramics have been prepared by columbite method by using (i) MgO and (ii)(MgCO(3))(4)center dot Mg(OH)(2)center dot 4H(2)O precursors (denoted as PLMN1 and PLMN2 respectively). The dielectric data show relaxor behaviour in the frequency range of 10 Hz to 1 MHz, with dielectric constant values in the range of 310-350 for PLMN1 and 240-260 for PLMN2 and a permittivity maxima at the temperature T(m)=179 K and T(m)=174K, respectively (for f=1 MHz). The Raman spectra proved the stability of the nanopolar order far above T, as observed in many Pb-based relaxors. This is demonstrated by the existence of some modes (at similar to 300, 500 and 780 cm(-1)) up to around 773K. Anomalies of some Raman modes (integrated intensity and FWHM) have been found in the range of T(m), proving the phase transition from pseudo-cubic relaxor to cubic paraelectric state, where the stability of the vibration modes is affected by the fluctuations associated to the phase transitions. (C) 2010 Elsevier B.V. All rights reserved

Preparation and magnetic properties of the (1-x)BiFeO3 \u2013 xBaTiO3 solid solutions

(1-x)BiFeO3 \u2013 xBaTiO3 (0 64 x 64 0.30) ceramics were prepared by the solid state reaction method. After sintering at 800\ub0C/1h and slow cooling, single phase compositions were obtained for both presintered and sintered samples, including the composition x=0, which was rarely reported. The gradual attenuation of the rhombohedral distortion with the increase of BaTiO3 content was pointed out. The BaTiO3 admixture acts also as inhibitor for the grain growth process, contributing to the decrease of the average grain size. The compositions corresponding to x=0.30 exhibits multiferroic behavior at room temperature, having both antiferromagnetic and ferroelectric order and low losses (< 3%). The Raman activity proved the existence of the local non-centrosymmetry and of some grain boundary characteristics at room temperature. The magnetic data indicates a composition-dependent antiferromagnetic character