Amyotrophic lateral sclerosis phenotypes significantly differ in terms of magnetic susceptibility properties of the precentral cortex

The aim of our study was to investigate whether the magnetic susceptibility varies according to the amyotrophic lateral sclerosis (ALS) phenotypes based on the predominance of upper motor neuron (UMN)/lower motor neuron (LMN) impairment. We retrospectively collected imaging and clinical data of 47 ALS patients (12 with UMN predominance (UMN-ALS), 16 with LMN predominance (LMN-ALS), and 19 with no clinically defined predominance (Np-ALS)). We further enrolled 23 healthy controls (HC) and 15 ALS mimics (ALS-Mim). These participants underwent brain 3-T magnetic resonance imaging (3-T MRI) with T1-weighted and gradient-echo multi-echo sequences. Automatic segmentation and quantitative susceptibility mapping (QSM) were performed. The skewness of the susceptibility values in the precentral cortex (SuscSKEW) was automatically computed, compared among the groups, and correlated to the clinical variables. The Kruskal-Wallis test showed significant differences in terms of SuscSKEW among groups (χ2(3) = 24.2, p < 0.001), and pairwise tests showed that SuscSKEW was higher in UMN-ALS compared to those in LMN-ALS (p < 0.001), HC (p < 0.001), Np-ALS (p = 0.012), and ALS-Mim (p < 0.001). SuscSKEW was highly correlated with the Penn UMN score (Spearman's rho 0.612, p < 0.001). This study demonstrates that the clinical ALS phenotypes based on UMN/LMN sign predominance significantly differ in terms of magnetic susceptibility properties of the precentral cortex. Combined MRI-histopathology investigations are strongly encouraged to confirm whether this evidence is due to iron overload in UMN-ALS, unlike in LMN-ALS. • Magnetic susceptibility in the precentral cortex reflects the prevalence of UMN/LMN impairment in the clinical ALS phenotypes. • The degree of UMN/LMN impairment might be well described by the automatically derived measure of SuscSKEW in the precentral cortex. • Increased SuscSKEW in the precentral cortex is more relevant in UMN-ALS patients compared to those in Np-ALS and LMN-ALS patients

Eimerídeos em coelhos de criações comerciais do estado do Rio Grande do Sul, Brasil : resultados parciais

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Peri-lead edema and local field potential correlation in post-surgery subthalamic nucleus deep brain stimulation patients

Implanting deep brain stimulation (DBS) electrodes in patients with Parkinson's disease often results in the appearance of a non-infectious, delayed-onset edema that disappears over time. However, the time window between the DBS electrode and DBS stimulating device implant is often used to record local field potentials (LFPs) which are used both to better understand basal ganglia pathophysiology and to improve DBS therapy. In this work, we investigated whether the presence of post-surgery edema correlates with the quality of LFP recordings in eight patients with advanced Parkinson's disease implanted with subthalamic DBS electrodes. The magnetic resonance scans of the brain after 8.5 +/- 1.5 days from the implantation surgery were segmented and the peri-electrode edema volume was calculated for both brain hemispheres. We found a correlation (rho = -0.81, p < 0.0218, Spearman's correlation coefficient) between left side local field potentials of the low beta band (11-20 Hz) and the edema volume of the same side. No other significant differences between the hemispheres were found. Despite the limited sample size, our results suggest that the effect on LFPs may be related to the edema localization, thus indicating a mechanism involving brain networks instead of a simple change in the electrode-tissue interface

Role of prothrombotic polymorphisms in successful or unsuccessful aging

The study of the genetic profile of centenarians aims to identify the genes and allelic variants which may influence a greater life expectancy and that can be considered as predisposing factors associated to the aging diseases, such as Alzheimer. Centenarians, that represent a cohort of selected survivors, show an hypercoagulability state characterised by striking signs of high coagulation enzyme activity, as directly assessed by the tested higher plasma level of some important factors involved in the haemostasis balance. Anyway, these individuals seem to have a reduced susceptibility to dementia, as well as to cardiovascular events. In this study we analyze the frequencies of Leiden Factor V polymorphism (G1691A), and G20210A of prothrombin (FII) in three cohorts of subjects: patients with Alzheimer\u2019s disease (unsuccessful aging), nonagenarians (successful aging) and young healthy controls, to assess whether allelic variants associated to the modification of haemostatic system function, may play a role in the protection or susceptibility to Alzheimer disease, as well as to reach a successful aging. No significant differences were observed in the frequencies of the three groups studied. These results indicate that the presence or absence of the gene variants examined did not influence the achievement of advanced age and are not risk factors for Alzheimer\u2019s disease. The state of hypercoagulability and the possession of these risk alleles appear to be compatible with the achievement of longevity and are not implied as risk factors in Alzheimer disease development

Mini Quadrotor UAV: Design and Experiment

The purpose of this work is to design a new-layout quadrotor UAS for experimental customized control systems validation. Geometrical and structural properties have been computed, whereas commercial-off-the-shelf equipments have been selected. The flight control system, both hardware and software has been custom developed; the same applies for the mathematical model describing the flight dynamics. Two Proportional- Derivative (PD) controllers have been designed and experimentally tested. A different control strategy with a state feedback controller has been implemented, assigning a robust eigenstructure and the desired dynamic specifications. An adaptive algorithm, which guarantees uniformly bounded response for both the inputs and the outputs, has been presented. A L1 adaptive controller has been studied and implemented, including the state predictor, the adaptive and the control laws. Tests with PD controller have shown slowly stable response even if numerical and vibrational noise carried on. In conclusion L1 adaptive controller permits to obtain optimal response characteristics and the low pass filter integrated in control law, combined with a Kalman filter, can reduce noise and correlate data between different sensor

Steroid Pulse Therapy for Severe Central Nervous System Involvement in Shiga Toxin-Producing Escherichia coli-Related Hemolytic Uremic Syndrome

We report on the case of a 7-year-old boy with Shiga toxin-producing Escherichia coli-related hemolytic uremic syndrome (STEC-HUS), initially presenting with abdominal pain as the only clinical feature and thus requiring differential diagnosis with a surgical emergency. Diagnosis of STEC-HUS was made with the appearance of bloody diarrhea and renal function impairment, and the clinical picture rapidly progressed to multiorgan failure. Relatively late and severe central nervous system (CNS) involvement was present, characterized by subacute encephalitis progressing to coma, which became apparent when the acute phase of thrombotic microangiopathy was resolving. Therefore, neurologic manifestations were thought to be related to reperfusion damage to the CNS and high-dose IV steroid pulse therapy was empirically administered. Following this therapeutic scheme, neurologic involvement resolved with no sequelae. This case offers several points of discussion on the clinical presentation and the diagnostic approach to STEC-HUS, on the related neurologic complications, and on a novel approach to their management

Neural correlates of empathic impairment in the behavioral variant of frontotemporal dementia

Abstract Objective: Loss of empathy is a symptom of the behavioral variant of frontotemporal dementia (bvFTD), constituting a clue for early diagnosis. In this study, we directly compared two empathy components (intention attribution [IA] and emotion attribution [EA]), correlating them with possible specific patterns of gray-matter density reduction within the mentalizing network. Methods: We evaluated IA and EA in 18 mild bvFTD patients compared with 36 healthy controls (HCs) using a single nonverbal test. A subgroup entered a voxel-based morphometry study. Results: Compared with HC, bvFTD patients showed IA and EA impairments. EA performance correlated with gray-matter reduction in the right amygdala, left insula, and posterior-superior temporal sulcus extending into the temporoparietal junction. Conclusion: We proved an empathic impairment, with the ability to infer emotional states showing the most severe deficit. These results provide further evidence of selective disease-specific vulnerability of the limbic and frontoinsular network in bvFTD and highlight the usefulness of empathy assessment in early patients

Delayed Perihematomal Hypoperfusion is associated with Poor Outcome in Intracerebral Hemorrhage

Background: we aimed to characterize the temporal evolution and prognostic significance of perihematomal perfusion in acute intracerebral hemorrhage (ICH). Methods: single center prospective cohort of patients with primary spontaneous ICH receiving computed tomography perfusion (CTP) within 6 h from onset (T0) and at 7 days (T7). Cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT) were measured in the manually outlined perihematomal low-density area. Poor functional prognosis (modified Rankin Scale 3-6) at 90 days was the outcome of interest and predictors were explored with multivariable logistic regression. Results: a total of 150 patients were studied, of whom 52 (34.7%) had a mRS 3-6 at 90 days. Perihematomal perfusion decreased from T0 to T7 in all patients but the magnitude of CBF and CBV reduction was larger in patients with unfavorable outcome (median CBF change -7.8 vs. -6.0 mL/100g/min, p&lt;0.001 and median CBV change -0.5 vs. -0.4 mL/100g, p=0.010 respectively). This finding remained significant after adjustment for confounders (odds ratio [OR] for 1mL/100g/min CBF reduction: 1.33, 95% confidence interval [CI] (1.15-1.55), p&lt;0.001; OR for 0.1 mL/100g CBV reduction 1.67, 95% CI 1.18-2.35, p=0.004). The presence of CBF&lt;20 mL/100g/min at T7 was then demonstrated as an independent predictor of poor functional outcome (adjusted OR: 2.45, 95% CI 1.08-5-54, p=0.032). Conclusion: perihemorrhagic hypoperfusion becomes more severe in the days following acute ICH and is independently associated with poorer outcome. Understanding the underlying biological mechanisms responsible for delayed decrease in perihematomal perfusion is a necessary step towards outcome improvement in patients with ICH