183 research outputs found
Collagen scaffold and lipoaspirate fluid - Derived stem cells for the treatment of cartilage defects in a Rabbit Model
The purpose of the present study was to assess and compare the chondroregenerative properties of PLA (processed lipoaspirate) and LAF (lipoaspirate fluid) cells, in a preclinical rabbit model of knee cartilage defect. The defects were repaired by a collagen I/III scaffold and added LAF-cells, PLA-cells or no cells, upon the study group. The results showed that collagen scaffolds seeded with LAF-derived stem cells appear to have slightly better activity and outcomes when compared to PLA-cells, in terms of cartilage regeneration
Erratum to: Comparative assessment of image quality for coronary CT angiography with iobitridol and two contrast agents with higher iodine concentrations: iopromide and iomeprol. A multicentre randomized double-blind trial
Unfortunately, there is amistake in the section Results, Clinical safety. While the text states that “no severe AEs were reported”, in fact one severe AE was reported in the iomeprol group (one severe injection site pain assessed as possibly related to contrast agent), as shown in Table 5. In addition, the name of the author Jean-François Paul was rendered incorrectly in the original publication but has since been corrected. The authors apologize for these mistakes
Subcycle Quantum Electrodynamics
Besides their stunning physical properties which are unmatched in a classical
world, squeezed states of electromagnetic radiation bear advanced application
potentials in quantum information systems and precision metrology, including
gravitational wave detectors with unprecedented sensitivity. Since the first
experiments on such nonclassical light, quantum analysis has been based on
homodyning techniques and photon correlation measurements. These methods
require a well-defined carrier frequency and photons contained in a quantum
state need to be absorbed or amplified. They currently function in the visible
to near-infrared and microwave spectral ranges. Quantum nondemolition
experiments may be performed at the expense of excess fluctuations in another
quadrature. Here we generate mid-infrared time-locked patterns of squeezed
vacuum noise. After propagation through free space, the quantum fluctuations of
the electric field are studied in the time domain by electro-optic sampling
with few-femtosecond laser pulses. We directly compare the local noise
amplitude to the level of bare vacuum fluctuations. This nonlinear approach
operates off resonance without absorption or amplification of the field that is
investigated. Subcycle intervals with noise level significantly below the pure
quantum vacuum are found. Enhanced fluctuations in adjacent time segments
manifest generation of highly correlated quantum radiation as a consequence of
the uncertainty principle. Together with efforts in the far infrared, this work
opens a window to the elementary quantum dynamics of light and matter in an
energy range at the boundary between vacuum and thermal background conditions.Comment: 19 pages, 4 figure
Renal artery stenosis evaluation: diagnostic performance of gadobenate dimeglumine-enhanced MR angiography--comparison with DSA
PURPOSE: To prospectively determine diagnostic performance and safety of contrast material-enhanced (CE) magnetic resonance (MR) angiography with 0.1 mmol per kilogram of body weight gadobenate dimeglumine for depiction of significant steno-occlusive disease (> or =51% stenosis) of renal arteries, with digital subtraction angiography (DSA) as reference standard. MATERIALS AND METHODS: This multicenter study was approved by local institutional review boards; all patients provided written informed consent. Patient enrollment and examination at centers in the United States complied with HIPAA. Two hundred ninety-three patients (154 men, 139 women; mean age, 61.0 years) with severe hypertension (82.2%), progressive renal failure (11.3%), and suspected renal artery stenosis (6.5%) underwent CE MR angiography with three-dimensional spoiled gradient-echo sequences after administration of 0.1 mmol/kg gadobenate dimeglumine at 2 mL/sec. Anteroposterior and oblique DSA was performed in 268 (91.5%) patients. Three independent blinded reviewers evaluated CE MR angiographic images. Sensitivity, specificity, and accuracy of CE MR angiography for detection of significant steno-occlusive disease (> or =51% vessel lumen narrowing) were determined at segment (main renal artery) and patient levels. Positive and negative predictive values and positive and negative likelihood ratios were determined. Interobserver agreement was analyzed with generalized kappa statistics. A safety evaluation (clinical examination, electrocardiogram, blood and urine analysis, monitoring for adverse events) was performed. RESULTS: Of 268 patients, 178 who were evaluated with MR angiography and DSA had significant steno-occlusive disease of renal arteries at DSA. Sensitivity, specificity, and accuracy of CE MR angiography for detection of 51% or greater stenosis or occlusion were 60.1%-84.1%, 89.4%-94.7%, and 80.4%-86.9%, respectively, at segment level. Similar values were obtained for predictive values and for patient-level analyses. Few CE MR angiographic examinations (1.9%-2.8%) were technically inadequate. Interobserver agreement for detection of significant steno-occlusive disease was good (79.9% agreement; kappa = 0.69). No safety concerns were noted. CONCLUSION: CE MR angiography performed with 0.1 mmol/kg gadobenate dimeglumine, compared with DSA, is safe and provides good sensitivity, specificity, and accuracy for detection of significant renal artery steno-occlusive disease
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