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Fingolimod is one of the few oral drugs available for the treatment of multiple sclerosis (MS), a chronic, inflammatory, demyelinating and neurodegenerative disease. The mechanism of action proposed for this drug is based in the phosphorylation of the molecule to produce its active metabolite fingolimod phosphate (FP) which, in turns, through its interaction with S1P receptors, triggers the functional sequestration of T lymphocytes in lymphoid nodes. On the other hand, part if not most of the damage produced in MS and other neurological disorders seem to be mediated by reactive oxygen species (ROS), and mitochondria is one of the main sources of ROS. In the present work, we have evaluated the anti-oxidant profile of FP in a model of mitochondrial oxidative damage induced by menadione (Vitk3) on neuronal cultures. We provide evidence that incubation of neuronal cells with FP alleviates the Vitk3-induced toxicity, due to a decrease in mitochondrial ROS production. It also decreases regulated cell death triggered by imbalance in oxidative stress (restore values of advanced oxidation protein products and total thiol levels). Also restores mitochondrial function (cytochrome c oxidase activity, mitochondrial membrane potential and oxygen consumption rate) and morphology. Furthermore, increases the expression and activity of protective factors (increases Nrf2, HO1 and Trx2 expression and GST and NQO1 activity), being some of these effects modulated by its interaction with the S1P receptor. FP seems to increase mitochondrial stability and restore mitochondrial dynamics under conditions of oxidative stress, making this drug a potential candidate for the treatment of neurodegenerative diseases other than MS. Image 1 • First evidence of fingolimod phosphate protection against oxidative damage in neurons. • Fingolimod phosphate recovers mitochondrial function in neuronal cells after oxidative damage. • Fingolimod phosphate restores mitochondrial distribution in neurons after oxidative damage. • S1P receptors are involved in the recovery of neuronal mitochondrial function after oxidative damage. [ABSTRACT FROM AUTHOR]

Background Postoperative blood loss may be a risk factor for allogeneic blood transfusion ( ABT) in patients undergoing subcapital hip fracture ( SHF) repair. We investigated the utility and costs of using a low-vacuum reinfusion drain (Bellovac ABT) within a blood management protocol for reducing ABT requirements in consecutive SHF. Methods The blood management protocol consisted of the application of a restrictive transfusion trigger (Hb < 8 g/dl), the peri-operative administration of IV iron sucrose (3 × 200 mg/48 h) ± recombinant erythropoietin (1 × 40 000 IU sc) and the use of Bellovac ABT (Group 2, n = 117). An immediate previous SHF series managed without Bellovac ABT served as control (Group 1, n = 138). Results Overall, 72 out of 255 (28%) received at least one ABT unit (2·1 ± 1·0 U/transfused patient) without differences between groups. However, in the subgroup of patients with admission Hb < 13 g/dl, the use of Bellovac ABT reduced postoperative ABT rates (16% vs. 46%, for groups 2 and 1, respectively; P = 0·001), although only 3 were reinfused, and was cost-saving. The use of Bellovac ABT also resulted in fewer wound bleeding complications, but there were no differences in Hb at postoperative days 7 and 30 between groups. Conclusions In SHF patients with admission Hb < 13 g/dl and managed with peri-operative IV iron ± recombinant erythropoietin plus restrictive transfusion indication, the use of Bellovac ABT was associated with reduced ABT requirements, without increasing postoperative complications, and cost-savings. [ABSTRACT FROM AUTHOR]

Background and purpose Patients with the non-fluent/agrammatic variant of primary progressive aphasia (nfvPPA) may develop atypical parkinsonian syndromes. However, there is no current biomarker to assess which patients are at high risk of developing parkinsonism. 123I-2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl)-nortropane (123I-FP-CIT)-SPECT detects striatal dopamine dysfunction in vivo. The objective of the present study was to study whether non-fluent/agrammatic patients without parkinsonism at baseline present decreased striatal 123I-FP-CIT uptake. Methods Visual and semi-quantitative assessments of the striatal 123I-FP-CIT uptake ratio were carried out in 15 patients with nfvPPA, eight patients with the logopenic variant of PPA (lvPPA) and 18 controls. To rule out progranulin mutations or underlying Alzheimer's disease (AD), serum progranulin levels and cerebrospinal fluid (CSF) biomarkers of AD (Aβ42, total-tau, phosphorylated-tau181) were determined. A second 123I-FP-CIT-SPECT analysis in the biomarker-enriched groups was also carried out. Results Patients with nfvPPA presented reduced striatal 123I-FP-CIT binding, especially in the left hemisphere ( P = 0.002), compared with controls. All lvPPA patients had normal striatal 123I-FP-CIT uptake. 123I-FP-CIT striatal binding in nfvPPA patients with normal progranulin and CSF biomarker levels (nfvPPA/bio-) was also significantly reduced ( P < 0.05) compared with lvPPA patients with positive AD biomarkers. Sixty-four per cent (9/14) of nfvPPA patients and 80% of nfvPPA/bio- patients (8/10) showed a diminished individual left striatal 123I-FP-CIT uptake ratio. On follow-up, seven nfvPPA/bio- patients developed parkinsonism (median 1.9 years; range 1.2-2.9), six of them with baseline reduced 123I-FP-CIT uptake. Conclusions Reduced striatal tracer uptake in nfvPPA patients prior to clinical parkinsonism can be detected by 123I-FP-CIT-SPECT, especially in those with nfvPPA/bio-, suggesting subclinical nigrostriatal degeneration. Decreased striatal 123I-FP-CIT binding might identify PPA patients at increased risk of developing atypical parkinsonian syndromes, probably related to tau-pathology. [ABSTRACT FROM AUTHOR]

Presents a study that characterized fan-beam collimators' point spread functions (PSF) by using Monte Carlo simulation. Description of the simulation code; Comparison of the sensitivity values obtained from simulated PSF for a fan-beam collimator with those obtained from experimental PSF; Results and discussion.

Presents a study that proposed a numerical method of obtaining the geometric point spread function (PSF) in cast fan-beam collimators with hexagonal holes. Description of the numerical method; Changes in the geometric component of the PSF; Experimental measurements employed; Results and discussion.