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Background: Beta thalassemia major (BT) is an inherited blood disorder caused by reduced or absent synthesis of the hemoglobin beta chains, associated with profound anemia, jaundice, splenomegaly, expanded bone marrow volume, siderosis and cardiomegaly. Because of repeated blood transfusions, BT patients are subjected to peroxidative tissue injury due to secondary iron overload., Objectives: The aim of the study was to analyze: 1) the total antioxidant capacity (TAC) value in BT patients (study group) and their healthy controls (control group) from Greece (Central Macedonia) and Italy (Sardinia); correlations between 2) the TAC and ferritin levels of BT patients, and 3) the TAC and ferritin values in BT patients with different chelation therapies., Material and Methods: The studied group consisted of 60 subjects diagnosed with BT (41 female, mean age: 41.5 ± 9.5 years) and 40 healthy controls matched with age and sex (31 female, mean age: 38.5 ± 3.7 years). Desferrioxamine (DFO) was the basic previous chelation regimen for all BT patients. Antioxidant activity was assayed spectrophotometrically, using a TAC Kit (Total Antioxidant Capacity Colorimetric assay kit, produced by Cayman Chemical Co.), and ferritin was assayed by immunoturbidimetry., Results: Lower levels of TAC were observed in BT patients of both countries when compared with controls (1.83 mmol/L vs 2.7 mmol/L in the Italian study group and controls and 2.42 mmol/L vs 3.2 mmol/L in the Greek study group and controls). There were no significant correlations between plasmatic TAC and ferritin. Furthermore, deferasirox was the only chelation treatment in which TAC showed a correlation in both regions., Conclusions: Our results potentially suggest that the reduced levels of TAC detectable in BT patients could demonstrate their reduced antioxidant defensive mechanisms.

Purpose: We examined different approaches aimed to deal with the signal fluctuation of pancreatic T2* values due to fat infiltration in order to obtain accurate estimates of iron overload., Methods: Pancreatic T2* values were assessed in 20 patients (13 females, 37.24 ± 9.12 years) enrolled in the Myocardial Iron Overload in Thalassemia network without and with the application of fat suppression-FS (T2*-NoFS and T2*-FS). T2* values were assessed in three different ways: (1) from the immediate fit (original T2*); (2) discarding the echoes until the achievement of a good visual concordance between the signal and the model (final&#95;vis T2*); (3) eliminating the echoes until the achievement of a fitting error (known) <5% (final&#95;thres T2*)., Results: For the T2*-NoFS sequence the original T2* values were significantly higher than the final&#95;vis T2* values (difference:4.8 ± 6.1 ms; P < 0.0001) and the final&#95;thres T2* values (difference:4.3 ± 6.1 ms; P = 0.006). For the T2*-FS sequence the original T2* values were comparable to final&#95;vis and final&#95;thres T2* values. The original T2*-FS values were significantly different from the original T2*-NoFS values. The final&#95;vis T2*-FS values were comparable to the final&#95;vis T2*-NoFS values and the final&#95;thresh T2*-FS values were comparable to the final&#95;thresh T2*-NoFS values. For both T2*-FS and T2*-NoFS sequences, the final&#95;thres T2* values were not significantly different from the final&#95;vis T2* values and no bias was present., Conclusions: In the clinical practice, an accurate pancreatic iron overload assessment should be done by applying FS and, when needed, by discarding the TEs until the fitting error goes below 5%.

The use of biological self-assembling materials, plant virus nanoparticles in particular, appears very intriguing as it allows a great choice of symmetries and dimensions, easy chemical and biological engineering of both surface and/or internal cavity as well as safe and rapid production in plants. In this perspective, we present an initial evaluation of the safety profile of two structurally different plant viruses produced in Nicotiana benthamiana L. plants: the filamentous Potato virus X and the icosahedral Tomato bushy stunt virus. In vitro haemolysis assay was used to test the cytotoxic effects, which could arise by pVNPs interaction with cellular membranes, while early embryo assay was used to evaluate toxicity and teratogenicity in vivo. Data indicates that these structurally robust particles, still able to infect plants after incubation in serum up to 24h, have neither toxic nor teratogenic effects in vitro and in vivo. This work represents the first safety-focused characterization of pVNPs in view of their possible use as drug delivery carriers., (Copyright © 2015 Elsevier B.V. All rights reserved.)

T2* maps obtained by the processing of multiecho MR sequences can be useful in several clinical applications. T2* map generation procedures should join a processing time compatible with on-line image analysis with a good precision in the entire T2* range of clinical interest. Fast generation of T2* maps can be achieved by the estimation of the T2* values by the weighted linear fitting of the logarithm of the signal (WLSL) method. This approach fails if the signal decay diverges from a pure exponential decay, as happens at low T2* values where the rapid decay in the signal intensity leads to a plateau in the later echo times (TE). The proposed method implements the automatic truncation of the signal decay curves to be fitted in order to compensate for the signal collapse at low T2* values, allowing the extension of the WLSL method through the entire clinical range of T2* values. Validation was performed on synthetic images and on 60 thalassemia major patients with different levels of myocardial iron overload. Phantom experiments showed that a 5% fitting error threshold represented the best compromise between T2* value measurement precision and processing time. A good agreement was found between T2* map pixel-wise measurements and ROI-based measurements performed by expert readers (CoV=1.84% in global heart T2*, CoV=5.8% in segmental analysis). In conclusion, the developed procedure was effective in generating correct T2* maps for the entire T2* clinical range., (Copyright © 2014 Elsevier Ltd. All rights reserved.)