Nora's lesion Genicon, Cyrielle; Rongieras, Frédéric; Le Moigne, François
Joint, bone, spine : revue du rhumatisme,
05/2022, Letnik:
89, Številka:
3
Journal Article
Recenzirano
Nora's lesion (bizarre parosteal osteochondromatous proliferation) is a rare pseudo-tumor in the class of surface osteocartilaginous lesions that mainly affects the phalanges of the extremities, ...diagnosed based on radiology and anatomical pathology findings.
Abstract Purpose The purpose of this study was to determine whether or not adding diffusion-weighted magnetic resonance imaging (DWI) to conventional magnetic resonance (MR) imaging sequences ...improves the characterization of small hepatocellular carcinoma (HCC) (≤2 cm) in the setting of cirrhotic liver compared to conventional sequences alone. Materials and Methods A total of 62 cirrhotic liver patients with 82 nodules smaller than 2 cm in diameter were enrolled, and all lesions were pathologically confirmed. For the first reading session, which included precontrast T1- and T2-weighted images and T1 dynamic contrast-enhanced images, preindicated lesions by a study coordinator were characterized by two radiologists. They determined the confidence levels in consensus for the presence of small HCC into four grades. In another session, respiratory-triggered diffusion-weighted MR images ( b factor=50, 400 and 800 s/mm2 ) were added to the previously reviewed images, and the same two radiologists again determined the confidence levels. The diagnostic performance of the combined DWI–conventional sequences set and the conventional sequences alone set was evaluated using receiver operating characteristic curves. Sensitivity and specificity values for characterizing small HCCs were also calculated. Results The area under the receiver operating characteristic curve for the second interpretation session (0.86) was significantly higher ( P =.038) than that of the first session (0.76). The sensitivity was significantly increased from 75.7% to 87.8% by adding DWI to the conventional sequences ( P =.015). No significant differences were observed for specificity values. Conclusion Adding DWI to conventional imaging modalities improves the diagnosis of small HCCs in the cirrhotic liver in terms of diagnostic performance and sensitivity by increasing reader confidence.
A new polarizing agent with superior performance in dynamic nuclear polarization experiments is introduced, and utilizes two TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) moieties connected through a ...rigid spiro tether (see structure). The observed NMR signal intensities were enhanced by a factor of 1.4 compared to those of TOTAPOL, a previously described TEMPO-based biradical with a flexible tether.
We have characterized the rigid binitroxide radical bis-TEMPO–bis-Ketal (bTbK) by continuous-wave (CW) and pulsed electron paramagnetic resonance (EPR) spectroscopy performed at X-band (9 GHz) and ...G-band (180 GHz) frequencies. bTbK has been successfully used for dynamic nuclear polarization (DNP)-enhanced solid-state nuclear magnetic resonance (SS-DNP) experiments based on the cross-effect, which involves two electrons and one nuclear spin, and gave very high signal enhancements. For a quantitative description of the polarization enhancements and their excitation frequency profile, a detailed information about the values and relative orientation of the magnetic hyperfine-, dipolar-,
g
-tensors and the exchange interaction of the two unpaired electron spins within the molecule is mandatory. We have determined these tensors and their relative orientation by CW-EPR spectra and pulsed electron double resonance experiments in frozen solution. The potential of using the cross-effect also for DNP in liquid solutions has been experimentally investigated by room-temperature high-field DNP experiments performed at 9.2 T.
An uncommon cause of malignant hypertension Le Moigne, François; Lamboley, Jean-Laurent; Vitry, Thierry ...
Archives of cardiovascular diseases,
10/2013, Letnik:
106, Številka:
10
Journal Article
Background
While computed tomography (CT) exams are the major cause of medical exposure to ionising radiation, there is increasing evidence that the potential radiation-induced risks must be ...documented. We investigated the impact of cellular models and individual factor on the deoxyribonucleic acid double-strand breaks (DSB) recognition and repair in human fibroblasts and mammary epithelial cells exposed to current chest CT scan conditions.
Method
Twelve human primary fibroblasts and four primary human mammary epithelial cell lines with different levels of radiosensitivity/susceptibility were exposed to a standard chest CT scan exam using adapted phantoms. Cells were exposed to a single helical irradiation (14.4 mGy) or to a topogram followed, after 1 min, by one single helical examination (1.1 mGy + 14.4 mGy). DSB signalling and repair was assessed through anti-γH2AX and anti-pATM immunofluorescence.
Results
Chest CT scan induced a significant number of γH2AX and pATM foci. The kinetics of both biomarkers were found strongly dependent on the individual factor. The topogram may also influence the biological response of radiosensitive/susceptible fibroblasts to irradiation. Altogether, our findings show that a chest CT scan exam may result in 2 to 3 times more unrepaired DSB in cells from radiosensitive/susceptible patients.
Conclusions
Both individual and tissue factors in the recognition and repair of DSB after current CT scan exams are important. Further investigations are needed to better define the radiosensitivity/susceptibility of individual humans.
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