Common mistakes and pitfalls in magnetic resonance imaging of the knee

This pictorial review presents an overview of common interpretation errors and pitfalls in magnetic resonance imaging (MRI) of the knee. Instead of being exhaustive, we will emphasize those pitfalls that are most commonly encountered by young residents or less experienced radiologists

Cost-effectiveness of [18F] fluoroethyl-L-tyrosine for temozolomide therapy assessment in patients with glioblastoma

Background and Purpose: Glioblastomas are the most aggressive of all gliomas. The prognosis of these gliomas, which are classified as grade IV tumors by the World Health Organization (WHO), is poor. Combination therapy, including surgery, radiotherapy, and chemotherapy has variable outcomes and is expensive. In light of rising healthcare costs, there are societal demands for the justification of medical expenses. Therefore, we calculated the cost-effectiveness of follow-up [F-18] fluoroethyl-L-tyrosine ([F-18] FET) positron emission tomography (PET) scans performed on patients with glioblastoma after surgery and before commencing temozolomide maintenance treatment. Materials and Methods: To determine the cost-effectiveness of follow-up [F-18] FET PET procedures, we examined published clinical data and calculated the associated costs in the context of Belgian healthcare. We subsequently performed one-way deterministic sensitivity analysis and Monte Carlo analysis on the calculated ratios. Results: The decision tree based on overall survival rates showed that the number of non-responders identified using PET was 57.14% higher than the number of non-responders identified using conventional MRI. Further, the decision tree based on progression-free survival rates revealed a comparable increase of 57.50% non-responders identified. The calculated cost of two required PET scans per patient during the follow-up treatment phase was 780.50 euros. Two cost-effectiveness ratios were determined for overall survival and progression-free survival rates. Both of these calculations yielded very similar results: incremental cost-effectiveness ratios of 1,365.86 and 1,357.38 euros, respectively, for each identified non-responder. The findings of the sensitivity analysis supported the calculated results, confirming that the obtained data were robust. Conclusion: Our comparative study of conventional MRI and [F-18] FET PET revealed that the latter is a valuable tool for predicting the treatment responses of patients with glioblastomas to follow-up temozolomide maintenance treatment while considering its cost-effectiveness. Thus, [F-18] FET PET scans enable clinical outcomes to be predicted accurately and at a low cost. Moreover, given the robustness of the data in the sensitivity analyses, the level of certainty of this outcome is acceptable

Encapsulation performance of layer-by-layer microcapsules for proteins

This study reports on the encapsulation efficiency of proteins in dextran sulfate/poly-l-arginine-based microcapsules, fabricated via layer-by-layer assembly (LbL). For this purpose, radiolabeled proteins are entrapped in CaCO3 microparticles, followed by LbL coating of the CaCO3 cores and subsequent dissolving of the CaCO3 using EDTA. To allow to improve protein encapsulation in LbL microcapsules, we studied all steps in the preparation of the microcapsules where loss of protein load might occur. The encapsulation efficiency of proteins in LbL microcapsules turns out to be strongly dependent on both the charge and molecular weight of the protein as well as on the number of polyelectrolyte bilayers the microcapsules consist of

Affinity study of novel gelatin cell carriers for fibronectin

In the present work, the gelatin/fibronectin affinity was evaluated using SPR, QCM and radiolabelling. The results indicate that type A gelatin films possess a higher affinity for Fn compared to type B gelatin. This is due to a combined hydrophobic and electrostatic interaction between gelatin type A and Fn. In a second part, the affinity of Fn for porous gelatin scaffolds was evaluated. The scaffolds were prepared by a cryogenic treatment and subsequent freeze-drying yielding type I and type II scaffolds which possess different pore geometries/sizes. The results indicate that the Fn density on the scaffolds can be fine-tuned by varying the Fn concentration, the gelatin type (A vs. 13), the pore size/geometry (type I vs. type II scaffolds)

Generation and in vivo characterization of a chimeric αvβ5-targeting antibody 14C5 and its derivatives

Background: Previous studies showed that radiolabeled murine monoclonal antibody (mAb) 14C5 and its Fab and F(ab')2 fragments, targeting αvβ5 integrin, have promising properties for diagnostic and therapeutic applications in cancer. To diminish the risk of generating a human anti-mouse antibody response in patients, chimeric variants were created. The purpose of this study was to recombinantly produce chimeric antibody (chAb) derivatives of the murine mAb 14C5 and to evaluate the in vitro and in vivo characteristics. Methods: In vitro stability, specificity, and affinity of radioiodinated chAb and fragments (Iodo-Gen method) were examined on high-expressing αvβ5 A549 lung tumor cells. In vivo biodistribution and pharmacokinetic characteristics were studied in A549 lung tumor-bearing Swiss Nu/Nu mice. Results: Saturation binding experiments revealed high in vitro affinity of radioiodinated chAb, F(ab')2, and Fab, with dissociation constants (KD) of 1.19 ± 0.19, 0.68 ± 0.10, and 2.11 ± 0.58 nM, respectively. ChAb 14C5 showed highest tumor uptake (approximately 10%ID/g) at 24 h post injection, corresponding with other high-affinity Abs. ChF(ab')2 and chFab fragments showed faster clearance from the blood compared to the intact Ab. Conclusions: The chimerization of mAb 14C5 and its fragments has no or negligible effect on the properties of the antibody. In vitro and in vivo properties show that the chAb 14C5 is promising for radioimmunotherapy, due to its high maximum tumor uptake and its long retention in the tumor. The chF(ab')2 fragment shows a similar receptor affinity and a faster blood clearance, causing less non-specific retention than the chAb. Due to their fast blood clearance, the fragments show high potential for radioimmunodiagnosis

Assessment of the pollution status of alluvial plains : a case study for the dredged sediment-derived soils along the Leie River

The concept of an integrated multifunctional river management is gaining importance. For major rivers, restoring the contact between rivers and alluvial plains is an important goal, as riparian areas have a specific role for several riverine processes. However, former and current human activities are an obstruction or a limitation for river restoration. We studied the influence of former dredging activities along the river Leie on the alluvial plain quality. A soil survey and an archive query for reconstructing the history of dredging operations were conducted simultaneously. The geographical impact expressed as topographical changes and covering of the original soil profile and related processes and biota was large. The pollution status of dredged sediment-derived soils was found to be far from negligible: concentrations of Cd, Cr, and Zn were, in 10% of the cases, higher than 20, 480, and 2800 mg kg(-1) DM, respectively. Both agriculture and nature rehabilitation on dredged sediment-derived soils can only be accepted after profound risk assessment, and management should focus on ecological risk reduction. Results indicate the importance of soil quality assessment in alluvial plains for an integrated river management, rather than a priori assuming pristine soil conditions. The collected "off-line" sediment data can be used as a reconstruction of past sediment pollution, especially when long-term sediment monitoring programs are not available