Optical coherence tomography attenuation imaging for lipid core detection:an ex-vivo validation study

Lipid-core atherosclerotic plaques are associated with disease progression, procedural complications, and cardiac events. Coronary plaque lipid can be quantified in optical coherence tomography (OCT) pullbacks by measurement of lipid arcs and lipid lengths; parameters frequently used in clinical research, but labor intensive and subjective to analyse. In this study, we investigated the ability of quantitative attenuation, derived from intravascular OCT, to detect plaque lipid. Lipid cores are associated with a high attenuation coefficient. We compared the index of plaque attenuation (IPA), a local quantitative measure of attenuation, to the manually measured lipid score (arc and length) on OCT images, and to the plaque characterization ex-vivo. We confirmed a correlation between the IPA and lipid scores (r2 > 0.7). Comparison to histology shows that high attenuation is associated with fibroatheroma, but also with macrophage presence. IPA is a robust, reproducible, and user-independent measure that facilitates quantification of coronary lipid, a potential tool in clinical research and in guiding percutaneous coronary intervention

La traduzione specializzata. Un approccio didattico professionale.

Il volume intende rappresentare uno strumento completo di orientamento sullo "stato dell'arte" delle metodologie di traduzione tecnico-scientifica, ma anche a fornire un valido supporto per la didattica e la prassi della traduzione. Nell'approccio proposto l'enfasi \ue8 posta sugli aspetti professionali della traduzione e sul ruolo del traduttore come esperto delle norme di scrittura dei testi tecnico-scientifici sia nella lingua di partenza sia nella lingua di arrivo. A due capitoli iniziali incentrati sulle lingue speciali - dimensioni di variazioni e aspetti macro- e microlinguistici - segue il capitolo 3 sui caratteri generali della traduzione e sulla preparazione dell'attivit\ue0 traduttiva, mentre il capitolo 4 \ue8 dedicato alla produzione della traduzione, ossia alla fase dell'effettiva riformulazione da una lingua all\u2019altra. Gli ultimi tre capitoli riguardano infine la qualit\ue0 in traduzione, la competenza del traduttore e gli aspetti professionali della traduzione

Efficacy and Reproducibility of Attenuation-Compensated Optical Coherence Tomography for Assessing External Elastic Membrane Border and Plaque Composition in Native and Stented Segments - An In Vivo and Histology-Based Study.

BACKGROUND:Attenuation-compensated (AC) technique was recently introduced to improve the plaque characterization of optical coherence tomography (OCT). Histological validation demonstrated promising results but the efficacy and reproducibility of this technique for assessing in-vivo tissue composition remains unclear.Methods and Results:OCT images portraying native (n=200) and stented (n=200) segments and 31 histological cross-sections were analyzed. AC-OCT appeared superior to conventional (C)-OCT in detecting the external elastic lamina (EEM) borders (76% vs. 65.5%); AC-OCT enabled larger EEM arc detection compared with C-OCT (174.2±58.7° vs. 137.5±57.9°; P<0.001). There was poor agreement between the 2 techniques for detection of lipid in native and lipid and calcific tissue in stented segments (κ range: 0.164-0.466) but the agreement of C-OCT and AC-OCT was high for calcific tissue in native segments (κ=0.825). Intra and interobserver agreement of the 2 analysts was moderate to excellent with C-OCT (κ range: 0.681-0.979) and AC-OCT (κ range: 0.733-0.892) for all tissue types in both native and stented segments. Ex-vivoanalysis demonstrated that C-OCT was superior to AC-OCT (κ=0.545 vs. κ=0.296) for the detection of the lipid component in native segments. CONCLUSIONS:The AC technique allows better delineation of the EEM but it remains inferior for lipid pool detection and neointima characterization. Combined AC- and C-OCT imaging may provide additional value for complete assessment of plaque and neointima characteristics

Design and Nuclear Magnetic Resonance (NMR) Structure Determination of the Second Extracellular Immunoglobulin Tyrosine Kinase A (TrkAIg2) Domain Construct for Binding Site Elucidation in Drug Discovery

The tyrosine kinase A (TrkA) receptor is a validated therapeutic intervention point for a wide range of conditions. TrkA activation by nerve growth factor (NGF) binding the second extracellular immunoglobulin (TrkAIg2) domain triggers intracellular signaling cascades. In the periphery, this promotes the pain phenotype and, in the brain, cell survival or differentiation. Reproducible structural information and detailed validation of protein–ligand interactions aid drug discovery. However, the isolated TrkAIg2 domain crystallizes as a β-strand-swapped dimer in the absence of NGF, occluding the binding surface. Here we report the design and structural validation by nuclear magnetic resonance spectroscopy of the first stable, biologically active construct of the TrkAIg2 domain for binding site confirmation. Our structure closely mimics the wild-type fold of TrkAIg2 in complex with NGF (1WWW.pdb), and the ¹H–¹⁵N correlation spectra confirm that both NGF and a competing small molecule interact at the known binding interface in solution