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Andreas Hjelm Brandt Kristoffer Lindskov Hansen Caroline Ewertsen Simon Holbek Jacob Bjerring Olesen Ramin Moshavegh Carsten Thomsen Jørgen Arendt Jensen Michael Bachmann Nielsen 《Ultrasound in medicine & biology》2018,44(8):1751-1761
Magnetic resonance phase contrast angiography (MRA) is the gold standard for blood flow evaluation. Spectral Doppler ultrasound (SDU) is the first clinical choice, although the method is angle dependent. Vector flow imaging (VFI) is an angle-independent ultrasound method. The aim of the study was to compare VFI- and SDU-estimated peak systolic velocities (PSV) of the common carotid artery (CCA) with PSV obtained by MRA. Furthermore, intra- and inter-observer agreement was determined. MRA estimates were significantly different from SDU estimates (left CCA: p?<?0.001, right CCA: p?<?0.001), but not from VFI estimates (left CCA: p?=?0.28, right CCA: p?=?0.18). VFI measured lower PSV in both CCAs compared with SDU (p?<?0.001) with improved precision (VFI: left: 24%, right: 18%; SDU: left 38%, right: 23%). Intra- and inter-observer agreement was almost perfect for VFI and SDU (inter-observer correlation coefficient: VFI 0.88, SDU 0.91; intra-observer correlation coefficient: VFI 0.96, SDU 0.97). VFI is more accurate than SDU in evaluating PSV compared with MRA. 相似文献
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Targeted ultradeep next‐generation sequencing as a method for KIT D816V mutation analysis in mastocytosis 下载免费PDF全文
Thomas Kristensen Sigurd Broesby‐Olsen Hanne Vestergaard Carsten Bindslev‐Jensen Michael Boe Mller 《European journal of haematology》2016,96(4):381-388
Next‐generation sequencing (NGS) is becoming increasingly used for diagnostic mutation analysis in myeloid neoplasms and may also represent a feasible technique in mastocytosis. However, detection of the KIT D816V mutation requires a highly sensitive method in most patients due to the typically low mutation levels. In this study, we established an NGS‐based KIT mutation analysis and analyzed the sensitivity of D816V detection using the Ion Torrent platform. Eighty‐two individual NGS analyses were included in the study. All samples were also analyzed using highly sensitive KIT D816V mutation‐specific qPCR. Measurements of the background level in D816V‐negative samples supported a cutoff for positivity of 0.2% in three different NGS panels. Clinical samples from patients with SM that tested positive using qPCR with a D816V allele burden >0.2% also tested positive using NGS. Samples that tested positive using qPCR with an allele burden <0.2% tested negative using NGS. We thereby demonstrate that caution should be taken when using the potentially very sensitive NGS technique for KIT D816V mutation analysis in mastocytosis, as many patients with SM have D816V mutation levels below the detection limit of NGS. A dedicated and highly sensitive KIT D816V mutation analysis therefore remains important in mastocytosis diagnostics. 相似文献
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Anke Augspach Joachim H. List Philipp Wolf Heike Bielek Carsten Schwan Ursula Els?sser-Beile Klaus Aktories Gudula Schmidt 《Toxins》2013,5(11):2241-2257
Prostate cancer is the most common malignancy, accounting for about 25% of all incident cases among men in industrialized countries. The human androgen-dependent prostate cancer cell line LNCaP, which is derived from a metastatic lesion of human prostatic adenocarcinoma, is frequently used to study prostate cancer associated signaling pathways in vitro. Recently it was described that Rho GTPase activation in these cells leads to apoptotic responses. We used the bacterial toxins CNFy and CNF1, which specifically and directly activate Rho GTPases by deamidation of a single glutamine. We asked whether these Rho activators could induce apoptosis in LNCaP cells. Our results indicate that RhoA activation, induced by CNFy, does lead to intrinsic apoptosis of the cells. Analysis of the underlying signaling pathway reveals that apoptosis induction requires the activity of Rho kinase (ROCK) and myosin activation, an apoptotic pathway previously identified in cancer stem cells. 相似文献
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Simon Holbek Kristoffer Lindskov Hansen Hamed Bouzari Caroline Ewertsen Matthias Bo Stuart Carsten Thomsen Michael Bachmann Nielsen Jørgen Arendt Jensen 《Ultrasound in medicine & biology》2017,43(10):2213-2220
Ultrasound (US) examination of the common carotid artery was compared with a through-plane magnetic resonance imaging (MRI) sequence to validate a recently proposed technique for 3-D US vector flow imaging. Data from the first volunteer examined were used as the training set, before volume flow and peak velocities were calculated for the remaining eight volunteers. Peak systolic velocities (PSVs) and volume flow obtained with 3-D US were, on average, 34% higher and 24% lower than those obtained with MRI, respectively. A high correlation was observed for PSV (r = 0.79), whereas a lower correlation was observed for volume flow (r = 0.43). The overall standard deviations were ±5.7% and ±5.7% for volume flow and PSV with 3-D US, compared with ±2.7% and ±3.2% for MRI. Finally, the data were re-processed with a change in the parameter settings for the echo-canceling filter to investigate its influence on overall performance. PSV was less affected by the re-processing, whereas the difference in volume flow between 3-D vector flow imaging and MRI was reduced to ?9%, and with an improved overall standard deviation of ±4.7%. The results illustrate the feasibility of using 3-D US for precise and angle-independent volume flow and PSV estimation in vivo. 相似文献