A comparison between plaque-based and vessel-based measurement for plaque component using volumetric intravascular ultrasound radiofrequency data analysis

Although percent plaque components on plaque-based measurement have been used traditionally in previous studies, the impact of vessel-based measurement for percent plaque components have yet to be studied. The purpose of this study was therefore to correlate percent plaque components derived by plaque- and vessel-based measurement using intravascular ultrasound Virtual Histology (IVUS-VH). The patient cohort comprised of 206 patients with de novo coronary artery lesions who were imaged with IVUS-VH. Age ranged from 35 to 88 years old, and 124 patients were male. Whole pullback analysis was used to calculate plaque volume, vessel volume, and absolute and percent volumes of fibrous, fibrofatty, necrotic core, and dense calcium. The plaque and vessel volumes were well correlated (r = 0.893, P < 0.001). There was a strong correlation between percent plaque components volumes calculated by plaque and those calculated by vessel volumes (fibrous; r = 0.927, P < 0.001, fibrofatty; r = 0.972, P < 0.001, necrotic core; r = 0.964, P < 0.001, dense calcium; r = 0.980, P < 0.001,). Plaque and vessel volumes correlated well to the overall plaque burden. For percent plaque component volume, plaque-based measurement was also highly correlated with vessel-based measurement. Therefore, the percent plaque component volume calculated by vessel volume could be used instead of the conventional percent plaque component volume calculated by plaque volume

Effect of statins on coronary bifurcation atherosclerosis: an intravascular ultrasound virtual histology study

This study is aimed at assessing by intravascular ultrasound virtual histology (VH-IVUS) the effect of statins on coronary bifurcation atherosclerosis in non-culprit vessels. In this non-randomized study, in 48 patients, 51 bifurcation atherosclerotic sites in non-culprit vessels without significant angiographic stenosis, underwent baseline and 12 months follow-up VH-IVUS. Patients received treatment with either simvastatin (20 mg daily, n = 24) or rosuvastatin (10 mg daily, n = 24) for the same period. VH-IVUS analysis of bifurcation lesions included the 5-mm proximal, bifurcation only (side-branch point) and 5-mm distal subsegments. Overall plaque and external elastic membrane volume decreased after 1 year (115.7 ± 35.5 to 106.1 ± 29.3 mm3, P < 0.001; and 241.0 ± 57.0 to 232.4 ± 54.2 mm3, P = 0.005, respectively). Similarly, overall dense calcium volume significantly increased (7.1 ± 5.3 to 11.0 ± 8.5 mm3, P < 0.010), while fibrous and fibrofatty volumes significantly decreased (36.9 ± 19.2 to 24.1 ± 11.7 mm3, P < 0.001; and 5.1 ± 3.8 to 2.3 ± 2.0 mm3, P < 0.001, respectively), and necrotic core volume did not change significantly (17.0 ± 11.1 to 19.8 ± 13.5 mm3, P = 0.053). There were no significant differences in compositional analysis between the simvastatin and rosuvastatin treatment groups. However, within groups, necrotic core volume significantly increased in the simvastatin treatment group (19.7 ± 13.9 to 24.3 ± 16.1 mm3, P = 0.029) but not in the rosuvastatin treatment group. (14.3 ± 6.7 to 15.6 ± 8.7 mm3, P = 0.423). The independent clinical predictors for reduction of necrotic core volume by multiple stepwise logistic regression analysis were the percent change of HDL-cholesterol level (P = 0.041, odds ratio: 1.052, 95% confidence interval (CI): 1.002 to 1.104) and the percent change of hsCRP level (P = 0.021, odds ratio: 0.989, 95% CI: 0.980 to 0.998). After 1 year, overall dense calcium volume significantly increased whilst fibrous and fibrofatty volumes significantly decreased; no significant change in the content of necrotic core was observed. Although changes in the volumes of all plaque components were not significantly different between the simvastatin and rosuvastatin treatment groups, halting of necrotic core progression was apparent in the rosuvastatin group

The assessment of Shin's method for the prediction of creatinine kinase-MB elevation after percutaneous coronary intervention: an intravascular ultrasound study

Cardiac enzyme release is common after percutaneous coronary intervention (PCI). At present there is no established relationship between the quantity of necrotic core and dense calcium, as assessed by Shin's method using intravascular ultrasound virtual histology (VH-IVUS), and post-PCI creatinine kinase-MB (CK-MB) elevation. A total of 112 consecutive patients with unstable angina and a normal pre-PCI CK-MB level were imaged using VH-IVUS. Patients were divided into 2 groups according to the presence (CK-MB group, n = 22) or absence (non CK-MB group, n = 90) of a post-PCI CK-MB elevation >1.0 the upper limit of normal (3.6 ng/ml). Using Shin's method contours were drawn around the IVUS catheter (instead of the lumen), and the vessel. Mean area and volume of necrotic core and dense calcium were significantly greater in CK-MB group than in non CK-MB group (1.7 ± 0.9 mm2vs. 0.9 ± 0.6 mm2, P < 0.001; 17.2 ± 8.8 mm3vs. 8.8 ± 5.8 mm3, P < 0.001, and 0.9 ± 0.6 mm2vs. 0.4 ± 0.4 mm2, P = 0.001; 9.1 ± 5.8 mm3vs. 3.9 ± 3.7 mm3, P < 0.001, respectively). Percent necrotic core and dense calcium areas calculated by external elastic membrane (EEM) area were significantly greater in CK-MB group than in non CK-MB group (11.9 ± 5.1 vs. 6.6 ± 4.0%, P < 0.001 and 6.5 ± 4.0 vs. 3.0 ± 2.9%, P 

Reproducibility of Shin's method for necrotic core and calcium content in atherosclerotic coronary lesions treated with bioresorbable everolimus-eluting vascular scaffolds using volumetric intravascular ultrasound radiofrequency-based analysis

Although Virtual Histology intravascular ultrasound (VH-IVUS) is increasingly used in clinical research, the reproducibility of plaque composition remains unexplored in significant coronary artery and stented lesions. The purpose of this study was to assess the reproducibility of necrotic core and calcium content in atherosclerotic coronary lesions that were treated with a bioresorbable everolimus-eluting vascular scaffold (BVS) using a new measurement method (Shin's method) by VH-IVUS. Eight patients treated with a BVS (Abbott Vascular, Santa Clara, CA, USA) were analyzed with serial VH-IVUS assessments, i.e., pre- and post-stenting, and at 6 months and 2 years follow-up. A total of 32 coronary segments were imaged to evaluate the reproducibility of volumetric VH-IVUS measurements. In Shin's method, contours are drawn around the IVUS catheter (instead of the lumen) and vessel. Overall, in the imaged coronary segment, for necrotic core and dense calcium volumes, the relative intra-observer differences were 0.30 ± 0.22, 0.19 ± 0.16% for observer 1 and 0.45 ± 0.41, 0.36 ± 0.47% for observer 2, respectively. The interobserver relative differences of necrotic core and dense calcium volumes were 0.51 ± 0.79 and 0.56 ± 1.01%, respectively. The present study demonstrates a good reproducibility for both, intra-observer and interobserver measurements using Shin's method. This method is suitable for the measurement of necrotic core and dense calcium using VH-IVUS in longitudinal studies, especially studies on bioresorbable scaffolds, because the degradation process will be fully captured independently of the location of the struts and their greyscale appearance

Assessment of the serial changes of vessel wall contents in atherosclerotic coronary lesion with bioresorbable everolimus-eluting vascular scaffolds using Shin's method: an IVUS study

Although serial changes in necrotic core and calcium are regarded as surrogates for the bioresorption process in patients treated with the bioresorbable everolimus-eluting vascular scaffolds (BVS), these temporal changes have not yet been fully investigated. Shin's method may be offer a more suitable technique for this analysis because it includes all the contents of both the lumen and vessel wall. The purpose of this study was to assess the serial changes of necrotic core and dense calcium content in coronary lesions that were treated with a BVS implant using Virtual Histology intravascular ultrasound (VH-IVUS) analyzed using Shin's method. A total of 29 patients (92 coronary segments) were imaged to evaluate the serial changes in necrotic core and dense calcium using Shin's method. Lesions treated with a BVS implant were analyzed with serial VH-IVUS assessments, i.e., pre- and post-stenting, and at 6 months and 2 years follow-up. In Shin's method contours are drawn around the IVUS catheter (instead of delineating the lumen) and the vessel. The mean necrotic core area decreased by 6.9% from post-stenting to 6 months (1.71 ± 1.03 mm2vs. 1.36 ± 0.91 mm2, P = 0.027), and by 20.5% (1.71 ± 1.03 mm2vs. 1.20 ± 0.70 mm2, P = 0.003) from post-steting to 2 years; while the mean dense calcium areas decreased by 27.2% (1.07 ± 0.55 mm2vs. 0.78 ± 0.64 mm2, P = 0.039) from post-stenting and 2 years. At 2 years, absolute necrotic core and dense calcium content were significantly decreased as compared to post-stenting values. The present study demonstrates that the bioresorption process in patients who undergoing BVS device implantation can be assessed using VH-IVUS analysed using Shin's method

Control of inflammation by stromal Hedgehog pathway activation restrains colitis

Inflammation disrupts tissue architecture and function, thereby contributing to the pathogenesis of diverse diseases; the signals that promote or restrict tissue inflammation thus represent potential targets for therapeutic intervention. Here, we report that genetic or pharmacologic Hedgehog pathway inhibition intensifies colon inflammation (colitis) in mice. Conversely, genetic augmentation of Hedgehog response and systemic small-molecule Hedgehog pathway activation potently ameliorate colitis and restrain initiation and progression of colitis-induced adenocarcinoma. Within the colon, the Hedgehog protein signal does not act directly on the epithelium itself, but on underlying stromal cells to induce expression of IL-10, an immune-modulatory cytokine long known to suppress inflammatory intestinal damage. IL-10 function is required for the full protective effect of small-molecule Hedgehog pathway activation in colitis; this pharmacologic augmentation of Hedgehog pathway activity and stromal IL-10 expression are associated with increased presence of CD4(+) Foxp3(+) regulatory T cells. We thus identify stromal cells as cellular coordinators of colon inflammation and suggest their pharmacologic manipulation as a potential means to treat colitis.11138Ysciescopu

A Study of Cosmic Ray Secondaries Induced by the Mir Space Station Using AMS-01

The Alpha Magnetic Spectrometer (AMS-02) is a high energy particle physics experiment that will study cosmic rays in the $\sim 100 \mathrm{MeV}$ to $1 \mathrm{TeV}$ range and will be installed on the International Space Station (ISS) for at least 3 years. A first version of AMS-02, AMS-01, flew aboard the space shuttle \emph{Discovery} from June 2 to June 12, 1998, and collected $10^8$ cosmic ray triggers. Part of the \emph{Mir} space station was within the AMS-01 field of view during the four day \emph{Mir} docking phase of this flight. We have reconstructed an image of this part of the \emph{Mir} space station using secondary $\pi^-$ and $\mu^-$ emissions from primary cosmic rays interacting with \emph{Mir}. This is the first time this reconstruction was performed in AMS-01, and it is important for understanding potential backgrounds during the 3 year AMS-02 mission.Comment: To be submitted to NIM B Added material requested by referee. Minor stylistic and grammer change

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02

Measurement of the splashback feature around SZ-selected Galaxy clusters with DES, SPT, and ACT

We present a detection of the splashback feature around galaxy clusters selected using the Sunyaev–Zel’dovich (SZ) signal. Recent measurements of the splashback feature around optically selected galaxy clusters have found that the splashback radius, rsp, is smaller than predicted by N-body simulations. A possible explanation for this discrepancy is that rsp inferred from the observed radial distribution of galaxies is affected by selection effects related to the optical cluster-finding algorithms. We test this possibility by measuring the splashback feature in clusters selected via the SZ effect in data from the South Pole Telescope SZ survey and the Atacama Cosmology Telescope Polarimeter survey. The measurement is accomplished by correlating these cluster samples with galaxies detected in the Dark Energy Survey Year 3 data. The SZ observable used to select clusters in this analysis is expected to have a tighter correlation with halo mass and to be more immune to projection effects and aperture-induced biases, potentially ameliorating causes of systematic error for optically selected clusters. We find that the measured rsp for SZ-selected clusters is consistent with the expectations from simulations, although the small number of SZ-selected clusters makes a precise comparison difficult. In agreement with previous work, when using optically selected redMaPPer clusters with similar mass and redshift distributions, rsp is ∼2σ smaller than in the simulations. These results motivate detailed investigations of selection biases in optically selected cluster catalogues and exploration of the splashback feature around larger samples of SZ-selected clusters. Additionally, we investigate trends in the galaxy profile and splashback feature as a function of galaxy colour, finding that blue galaxies have profiles close to a power law with no discernible splashback feature, which is consistent with them being on their first infall into the cluster