The introduction of arterial spin labelling (ASL) techniques in magnetic resonance imaging (MRI) has made feasible a non-invasive measurement of the cerebral blood flow (CBF). However, to date, the low signal-to-noise ratio of ASL gives us no option but to repeat the acquisition to accumulate enough data in order to get a reliable signal. The perfusion signal is then usually extracted by averaging across the repetitions. But the sample mean is very sensitive to outliers. A single incorrect observation can therefore be the source of strong detrimental effects on the perfusion-weighted image estimated with the sample mean. We propose to estimate robust ASL CBF maps with M-estimators to overcome the deleterious effects of outliers. The behavior of this method is compared to z-score thresholding as recommended in Tan et al. (Journal of Magnetic Resonance Imaging 2009;29(5):1134-9.). Validation on simulated and real data is provided. Quantitative validation is undertaken by measuring the correlation with the most widespread technique to measure perfusion with MRI: dynamic susceptibility weighted contrast imaging.
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http://dx.doi.org/10.1016/j.mri.2014.01.016 | DOI Listing |
Int J Stroke
January 2025
Medical University of South Carolina, Charleston, SC, USA.
Background: The usual antithrombotic treatment for symptomatic intracranial atherosclerotic stenosis (ICAS) consists of dual treatment with clopidogrel and aspirin for 90 days followed by aspirin alone but the risk of recurrent stroke remains high up to 12 months. The Comparison of Anticoagulation and anti-Platelet Therapies for Intracranial Vascular Atherostenosis (CAPTIVA) trial was designed to determine whether other combinations of dual antithrombotic therapy are superior to clopidogrel and aspirin.
Methods: CAPTIVA is an ongoing, prospective, double-blinded, three-arm clinical trial at over 100 sites in the United States and Canada that will randomize 1683 high-risk subjects with a symptomatic infarct attributed to 70-99% stenosis of a major intracranial artery to 12 months of treatment with (1) ticagrelor (180 mg loading dose, then 90 mg twice daily), (2) low-dose rivaroxaban (2.
Viruses
January 2025
Surgical Neurology Branch, NINDS, NIH 10 Center Drive, Bethesda, MD 20892, USA.
Glioblastoma multiforme (GBM) is a devastating, aggressive primary brain tumor with poor patient outcomes and a five-year survival of less than 10%. Significant limitations to effective GBM treatment include poor drug delivery across the blood-brain barrier, drug resistance, and complex genetic tumor alterations. Gene therapy uses a mechanism different from other GBM therapies to reduce tumor growth and enhance antitumor immunity.
View Article and Find Full Text PDFViruses
January 2025
Department of Microbiology, Immunology and Transplantation, Rega Institute, KU Leuven, Herestraat 49, 3000 Leuven, Belgium.
The Rift Valley fever virus (RVFV) causes haemorrhagic fever, encephalitis, and permanent blindness and has been listed by the WHO as a priority pathogen. To study RVFV pathogenesis and identify small-molecule antivirals, we established a novel In Vivo model using zebrafish larvae. Pericardial injection of RVFV resulted in ~4 log viral RNA copies/larva, which was inhibited by the antiviral 2'-fluoro-2'-deoxycytidine.
View Article and Find Full Text PDFPharmaceutics
January 2025
CDL Research, University Medical Center Utrecht, 3584CX Utrecht, The Netherlands.
Background/objectives: Glioblastoma is the most common and lethal primary brain tumor. Patients often suffer from tumor- and treatment induced vasogenic edema, with devastating neurological consequences. Intracranial edema is effectively treated with dexamethasone.
View Article and Find Full Text PDFPharmaceutics
January 2025
Key Laboratory of Molecular Biophysics, Institute of Biophysics, School of Health Sciences & Biomedical Engineering, Hebei University of Technology, Tianjin 300401, China.
Brain diseases pose significant treatment challenges due to the restrictive nature of the blood-brain barrier (BBB). Recent advances in targeting macromolecules offer promising avenues for overcoming these obstacles through receptor-mediated transcytosis (RMT). We summarize the current progress in targeting brain drug delivery with macromolecules for brain diseases.
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