Typical lesions in the fetal nervous system: correlations between fetal magnetic resonance imaging and obstetric ultrasonography findings

Central nervous system (CNS) malformations play a role in all fetal malformations. Ultrasonography (US) is the best screening method for identifying fetal CNS malformations. A good echographic study depends on several factors, such as positioning, fetal mobility and growth, the volume of amniotic fluid, the position of the placenta, the maternal wall, the quality of the apparatus, and the sonographer’s experience. Although US is the modality of choice for routine prenatal follow-up because of its low cost, wide availability, safety, good sensitivity, and real-time capability, magnetic resonance imaging (MRI) is promising for the morphological evaluation of fetuses that otherwise would not be appropriately evaluated using US. The aim of this article is to present correlations of fetal MRI findings with US findings for the major CNS malformations

In vivo evaluation of cortical thickness with magnetic resonance imaging in patients with bipolar disorder

Changes in cortical thickness can be related to neuropsychiatric disorders and neurodegenerative processes. Previous studies have been conducted to characterize the pattern of changes in cortical thickness in several psychiatric diseases. The aim of the present study was to evaluate changes in cortical thickness with magnetic resonance imaging (MRI) in patients with bipolar disorder. Twenty-seven patients with bipolar disorder (14 male, 36.0 ± 16.2 years old; 13 female, 41.6 ± 10.7 years old) and 40 healthy controls (16 male, 36.0 ± 10.5 years old; 24 female, 37.0 ± 4.7 years old) underwent 3T MRI. Sagittal T1-weighted magnetization prepared rapid acquisition gradient echo images were acquired (voxel size, 1.33 mm³; 128 slices; in-plane matrix resolution, 256 × 256; flip angle, 7º; repetition time, 2530 ms; echo time, 3.39 ms; inversion time, 1100 ms). Cortical segmentation was performed using FreeSurfer 4.0.5. The results indicated both thinning and thickening of the cerebral cortex in patients with bipolar disorder compared with controls, depending on gender. Significant (p < .01) thickening was observed in the right hemisphere superior-parietal cortex in female patients with bipolar disorder, and significant (p < .05) thinning was observed in the left hemisphere caudal-anterior cingulate in male patients with bipolar disorder. The other regions did not show significant differences. The results suggest that an analysis of cortical thickness with MRI in patients with bipolar disorder may allow identification of areas that may be morphologically changed compared with controls. Demonstration of these alterations will elucidate the pathophysiology of bipolar disorder and may contribute to better therapies for this disorder

Correction: optimized labeling of bone marrow mesenchymal cells with superparamagnetic iron oxide nanoparticles and in vivo visualization by magnetic resonance imaging

Abstract Background Stem cell therapy has emerged as a promising addition to traditional treatments for a number of diseases. However, harnessing the therapeutic potential of stem cells requires an understanding of their fate in vivo. Non-invasive cell tracking can provide knowledge about mechanisms responsible for functional improvement of host tissue. Superparamagnetic iron oxide nanoparticles (SPIONs) have been used to label and visualize various cell types with magnetic resonance imaging (MRI). In this study we performed experiments designed to investigate the biological properties, including proliferation, viability and differentiation capacity of mesenchymal cells (MSCs) labeled with clinically approved SPIONs. Results Rat and mouse MSCs were isolated, cultured, and incubated with dextran-covered SPIONs (ferumoxide) alone or with poly-L-lysine (PLL) or protamine chlorhydrate for 4 or 24 hrs. Labeling efficiency was evaluated by dextran immunocytochemistry and MRI. Cell proliferation and viability were evaluated in vitro with Ki67 immunocytochemistry and live/dead assays. Ferumoxide-labeled MSCs could be induced to differentiate to adipocytes, osteocytes and chondrocytes. We analyzed ferumoxide retention in MSCs with or without mitomycin C pretreatment. Approximately 95% MSCs were labeled when incubated with ferumoxide for 4 or 24 hrs in the presence of PLL or protamine, whereas labeling of MSCs incubated with ferumoxide alone was poor. Proliferative capacity was maintained in MSCs incubated with ferumoxide and PLL for 4 hrs, however, after 24 hrs it was reduced. MSCs incubated with ferumoxide and protamine were efficiently visualized by MRI; they maintained proliferation and viability for up to 7 days and remained competent to differentiate. After 21 days MSCs pretreated with mitomycin C still showed a large number of ferumoxide-labeled cells. Conclusions The efficient and long lasting uptake and retention of SPIONs by MSCs using a protocol employing ferumoxide and protamine may be applicable to patients, since both ferumoxides and protamine are approved for human use.</p