ABSTRACT
In recent years, the targeted protein degradation technology has developed quickly, with proteolysis-targeting chimera (PROTAC) as the best-known strategy through exploring the ubiquitin-proteasome system. A number of new targeted protein degradation strategies have been emerging to expand the scope of protein degradation technology, including lysosome-targeting chimeras (LYTACs), autophagy-targeting chimeras (AUTACs), autophagosome-tethering compounds (ATTECs) and chimeras based on chaperone-mediated autophagy (CMA). The emerging methodologies have explored another important protein degradation system in eukaryotes-lysosomal systems, such as the endosome-lysosome pathway and the autophagy-lysosome pathway. This review summaries the mechanisms and features of different strategies for targeted protein degradation, with a special emphasis on the new targeted protein degradation technologies, such as their current status, advantages and limitations.
ABSTRACT
<p><b>OBJECTIVE</b>The objective was to qualitatively and quantitatively evaluate hepatic metastases using computed tomography (CT) virtual noncontrast (VNC) spectral imaging in a retrospective analysis.</p><p><b>METHODS</b>Forty hepatic metastases patients underwent CT scans including the conventional true noncontrast (TNC) and the tri-phasic contrast-enhanced dual energy spectral scans in the hepatic arterial, portal venous, and equilibrium phases. The tri-phasic spectral CT images were used to obtain three groups of VNC images including in the arterial (VNCa), venous (VNCv), and equilibrium (VNCe) phase by the material decomposition process using water and iodine as a base material pair. The image quality and the contrast-to-noise ratio (CNR) of metastasis of the four groups were compared with ANOVA analysis. The metastasis detection rates with the four nonenhanced image groups were calculated and compared using the Chi-square test.</p><p><b>RESULTS</b>There were no significant differences in image quality among TNC, VNCa and VNCv images (P > 0.05). The quality of VNCe images was significantly worse than that of other three groups (P < 0.05). The mean CNR of metastasis in the TNC and VNCs images was 1.86, 2.42, 1.92, and 1.94, respectively; the mean CNR of metastasis in VNCa images was significantly higher than that in other three groups (P < 0.05), while no statistically significant difference was observed among VNCv, VNCe and TNC images (P > 0.05). The metastasis detection rate of the four nonenhanced groups with no statistically significant difference (P > 0.05).</p><p><b>CONCLUSIONS</b>The quality of VNCa and VNCv images is identical to that of TNC images, and the metastasis detection rate in VNC images is similar to that in TNC images. VNC images obtained from arterial phase show metastases more clearly. Thus, VNCa imaging may be a surrogate to TNC imaging in hepatic metastasis diagnosis.</p>
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Contrast Media , Liver Neoplasms , Diagnosis , Diagnostic Imaging , Retrospective Studies , Sensitivity and Specificity , Tomography, X-Ray Computed , MethodsABSTRACT
Objective To explore the value of Multi-detector CT in spinal cord angiography. Methods Ten patients with initial MR and clinical findings suggestive of spinal cord vessel disease were performed CT spinal cord angiography.Among these,7 patients were performed DSA later within 1 week, and 4 patients were therapy by operation.CT protocol:Toshiba Aquilion 64 slice CT scanner,0.5 mm thickness,0.5/r,120 kV,350 mA,choose aortic arch level as inspection position,and use"surestart" technique with CT threshold 180 HU.Contrast medium was Iohexol(370 mg I/ml),with injection velocity of 6 ml/s.The total volume was 80 ml.The CT spinal cord angiography images were analyzed according to disease model,disease range,feeding artery,fistula,draining veins,and were compared with DSA and operation results.Results All CT spinal cord angiography images displayed spinal vessel malformation. Among these,3 patients were inner-medullary arteriovenous malformation;2 patients were peri-medullary arteriovenous fistula;5 patients were spinal dural arteriovenous fistula.All cases showed disease range,and draining veins clearly,one patient had two vessels that were false positive,and all the other cases showed feeding arteries clearly,which were confirmed by DSA.Conclusion There are great values for CT spinal angiography in diagnosing spinal vessel disease,it can be a screening exam before DSA.