Interleukin‐21 (IL‐21) synergizes with IL‐2 to enhance T‐cell receptor‐induced human T‐cell proliferation and counteracts IL‐2/transforming growth factor‐β‐induced regulatory T‐cell development

Interleukin‐2 (IL‐2) is a mainstay for current immunotherapeutic protocols but its usefulness in patients is reduced by severe toxicities and because IL‐2 facilitates regulatory T (Treg) cell development. IL‐21 is a type I cytokine acting as a potent T‐cell co‐mitogen but less efficient than IL‐2 in sustaining T‐cell proliferation. Using various in vitro models for T‐cell receptor (TCR)‐dependent human T‐cell proliferation, we found that IL‐21 synergized with IL‐2 to make CD4⁺ and CD8⁺ T cells attain a level of expansion that was impossible to obtain with IL‐2 alone. Synergy was mostly evident in naive CD4⁺ cells. IL‐2 and tumour‐released transforming growth factor‐β (TGF‐β) are the main environmental cues that cooperate in Treg cell induction in tumour patients. Interleukin‐21 hampered Treg cell expansion induced by IL‐2/TGF‐β combination in naive CD4⁺ cells by facilitating non‐Treg over Treg cell proliferation from the early phases of cell activation. Conversely, IL‐21 did not modulate the conversion of naive activated CD4⁺ cells into Treg cells in the absence of cell division. Treg cell reduction was related to persistent activation of Stat3, a negative regulator of Treg cells associated with down‐modulation of IL‐2/TGF‐β‐induced phosphorylation of Smad2/3, a positive regulator of Treg cells. In contrast to previous studies, IL‐21 was completely ineffective in counteracting the suppressive activity of Treg cells on naive and memory, CD4⁺ and CD8⁺ T cells. Present data provide proof‐of‐concept for evaluating a combinatorial approach that would reduce the IL‐2 needed to sustain T‐cell proliferation efficiently, thereby reducing toxicity and controlling a tolerizing mechanism responsible for the contraction of the T‐cell response.     

CANVAS: a late onset ataxia due to biallelic intronic AAGGG expansions

Journal of Neurology - The ataxias are a group of disorders that manifest with balance, movement, speech and visual problems. They can arise due to dysfunction of the cerebellum, the vestibular...     

Real world experience with teriflunomide in multiple sclerosis: the TER-Italy study

Journal of Neurology - To identify baseline factors associated with disease activity in patients with relapsing–remitting multiple sclerosis (RRMS) under teriflunomide treatment. This was an...     

Stroke incidence and case fatality: a 9-year prospective population-based study in an elderly population of Bagheria,Italy

Neurological Sciences - The incidence of stroke in high-income countries has been on the decline; however, few epidemiological surveys have been conducted in recent years to specifically estimate...     

Ventricular activity cancellation in electrograms during atrial fibrillation with constraints on residuals’ power

During atrial fibrillation (AF), cancellation of ventricular activity from atrial electrograms (AEG) is commonly performed by template matching and subtraction (TMS): a running template, built in correspondence of QRSs, is subtracted from the AEG to uncover atrial activity (AA). However, TMS can produce poor cancellation, leaving high-power residues. In this study, we propose to modulate the templates before subtraction, in order to make the residuals as similar as possible to the nearby atrial activity, avoiding high-power ones. The coefficients used to modulate the template are estimated by maximizing, via Multi-swarm Particle Swarm Optimization, a fitness function. The modulated TMS method (mTMS) was tested on synthetic and real AEGs. Cancellation performances were assessed using: normalized mean squared error (NMSE, computed on simulated data only), reduction of ventricular activity (VDR), and percentage of segments (PP) whose power was outside the standard range of the atrial power. All testings suggested that mTMS is an improvement over TMS alone, being, on simulated data, NMSE and PP significantly decreased while VDR significantly increased. Similar results were obtained on real electrograms (median values of CS1 recordings PP: 2.44 vs. 0.38 p < 0.001; VDR: 6.71 vs. 8.15 p < 0.001).     

The effects of simulated obstructive apnea and hypopnea on arrhythmic potential in healthy subjects

Preliminary evidence supports an association between OSA and cardiac dysrhythmias. Negative intrathoracic pressure, as occurring during OSA, may provoke cardiac dysrhythmias. Thus, we aimed to study the acute effects of simulated apnea and hypopnea on arrhythmic potential and measures of cardiac repolarization [QT_C and T _peak to T _end intervals ( $ T_{\text{p}} T_{{{\text{e}}_{\text{c}} }} $ )] in humans. In 41 healthy volunteers, ECG was continuously recorded prior, during and after simulated obstructive hypopnea (inspiration through a threshold load), simulated apnea (Mueller maneuver), end-expiratory central apnea and normal breathing in randomized order. The number of subjects with premature beats was significantly higher during inspiration through a threshold load (n = 7), and the Mueller maneuver (n = 7) compared to normal breathing (n = 0) (p = 0.008 for all comparisons), but not during end-expiratory central apnea (n = 3, p = 0.125). Inspiration through a threshold load was associated with a non-significant mean (SD) increase of the QT_C interval [+5.4 (22.4) ms, 95 %CI ?1.7 to +12.4 ms, p = 0.168] and a significant increase of the $ T_{\text{p}} T_{{{\text{e}}_{\text{c}} }} $ interval [+3.7 (8.9) ms, 95 %CI +0.9 to +6.6 ms, p = 0.010]. The Mueller maneuver induced a significant increase of the QT_C interval [+8.3 (23.4) ms, 95 %CI 0.9 to +15.6 ms, p = 0.035] and the $ T_{\text{p}} T_{{{\text{e}}_{\text{c}} }} $ interval (+4.2 (8.2) ms, 95 %CI +1.6 to +6.8 ms, p = 0.002). There were no significant changes of the QT_C and $ T_{\text{p}} T_{{{\text{e}}_{\text{c}} }} $ intervals during central end-expiratory apnea. These data indicate that simulated obstructive apnea and hypopnea are associated with an increase of premature beats and prolongation of QT_C and $ T_{\text{p}} T_{{{\text{e}}_{\text{c}} }} $ intervals. Therefore, negative intrathoracic pressure changes may be a contributory mechanism for the association between OSA and cardiac dysrhythmias.     

Non-invasive indirect monitoring of intra-abdominal pressure using microwave reflectometry: system design and proof-of-concept clinical trial

Journal of Clinical Monitoring and Computing - Monitoring intra-abdominal pressure (IAP) has become a standard in intensive care units. Correlation between the abdominal wall’s thickness...