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Objectives: Left dorsolateral prefrontal cortex anodal transcranial direct current stimulation (tDCS) was applied in a group of patients with disorders of consciousness to determine the effects of modulation of spontaneous oscillatory brain activity., Methods: 12 patients in an unresponsive wakefulness syndrome (UWS) and 12 in a minimally conscious state (MCS) underwent 2-weeks active and 2-weeks sham tDCS. Neurophysiological assessment was performed with EEG power spectra and coherence analysis directly before and after each session., Results: An increase of power and coherence of the frontal and parietal alpha and beta frequency bands and significant clinical improvements were seen after the active tDCS in MCS patients. In contrast, UWS patients showed some local frontal changes in the slow frequencies. No treatment effect was observed after sham., Conclusions: tDCS could induce changes in cortical EEG oscillations, modulating the travel of alpha and beta waves between anterior and posterior brain areas when some cognitive functions were preserved. This plays an important role in consciousness by integrating cognitive-emotional processing with the state of arousal. In unresponsive people, brain integration seems to be lost., Significance: Our results further support the critical role of long-range fronto-parietal connections in consciousness and show the potential therapeutic utility of tDCS., (Copyright © 2018. Published by Elsevier B.V.)

Background: The outcome of stroke survivors is difficult to anticipate. While the extent of the anatomical brain lesion is only poorly correlated with the prognosis, functional measures of cortical synchrony, brain networks and cortical plasticity seem to be good predictors of clinical recovery. In this field, gamma (>30 Hz) cortical synchrony is an ideal marker of brain function, as it plays a crucial role for the integration of information, it is an indirect marker of Glutamate/GABA balance and it directly estimates the reserve of parvalbulin-positive neurons, key players in synaptic plasticity. In this study we measured gamma synchronization driven by external auditory stimulation with magnetoencephalography and tested whether it was predictive of the clinical outcome in stroke survivors undergoing intensive rehabilitation in a tertiary rehabilitation center., Material and Methods: Eleven stroke survivors undergoing intensive rehabilitation were prospectively recruited. Gamma synchrony was measured non-invasively within one month from stroke onset with magnetoencephalography, both at rest and during entrainment with external 40 Hz amplitude modulated binaural sounds. Lesion location and volume were quantitatively assessed through a high-resolution anatomical MRI. Barthel index (BI) and Functional Independence Measure (FIM) scales were measured at the beginning and at the end of the admission to the rehabilitation unit., Results: The spatial distribution of cortical gamma synchrony was altered, and the physiological right hemispheric dominance observed in healthy controls was attenuated or lost. Entrained gamma synchronization (but not resting state gamma synchrony) showed a very high correlation with the clinical status at both admission and discharge (both BI and FIM). Neither clinical status nor gamma synchrony showed a correlation with lesion volume., Conclusions: Cortical gamma synchrony related to auditory entrainment can be reliably measured in stroke patients. Gamma synchrony is strongly associated with the clinical outcome of stroke survivors undergoing rehabilitation., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Repetitive transcranial magnetic stimulation (rTMS) induces prolonged functional changes in the cerebral cortex in normal conditions and in altered states of consciousness. Its therapeutic effects have been variously documented., Objective: The aim of this study was to investigate the reactivity of electroencephalography (EEG) and the clinical response in six severely brain-injured patients in an altered state of consciousness (minimally conscious state [MCS] or vegetative state [VS]). EEG rhythm and brain excitability were measured before and after a protocol of high-frequency rTMS., Methods: All six patients underwent clinical and neurophysiological evaluation before rTMS and immediately thereafter. EEG data in resting state were acquired at the beginning of the exam (T0), after rTMS (T1), and 38 min after rTMS (T2). From these data the power values were computed using Fast Fourier Transform., Results: rTMS over the motor cortex induced long-lasting behavioral and neurophysiological modifications in only one patient in MCS. No significant clinical or EEG modifications were detected in any of the other patients, except for changes in motor threshold and motor evoked potential amplitude over the stimulated motor areas., Conclusions: The main finding of the study is the correlation between EEG reactivity and clinical response after rTMS. Reappearance of fast activity and an increase in slow activity were noted in the one patient with transitory arousal, whereas no significant reliable changes were observed in the other patients showing no clinical reactivity., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Objective: Studies on brain computer interfaces (BCIs) have been mainly concerned with algorithm improvement for better signal classification. Fewer studies, however, have addressed to date the role of cognitive mechanisms underlying the elicitation of brain-signals in BCIs. We tested the effect of visuospatial attention orienting on a P300-guided BCI, by comparing the effectiveness of three visual interfaces, which elicited different modalities of visuospatial attention orienting (exogenous vs. endogenous)., Methods: Twelve healthy participants performed 20 sessions, using the abovementioned P300-guided BCI interfaces to control a cursor. Brain waves were recorded on each trial and were subsequently classified on-line using an ad hoc algorithm. Each time the P300 was correctly classified, the cursor moved towards the target position., Results: The "endogenous" interface was associated with significantly higher performance than the other two interfaces during the testing sessions, but not in the follow-up sessions., Conclusions: Endogenous visuospatial attention orienting can be effectively implemented to increase the performance of P300-guided BCIs., Significance: The study of visuospatial attention underlying participants' performance is essential for implementing efficient visual BCIs., (Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

Objective: The limited evidence and inconsistency of purposeful behaviors in patients in a minimally conscious state (MCS) asks for objective electrophysiological marker of the level of consciousness. Here, a comparison between event-related potentials (ERPs) was investigated using different level of stimulus complexity., Methods: The patients in vegetative state were 11 and the MCS patients were 6 [corrected]. Three oddball paradigms with different level of complexity were applied: sine tones, the subject's own name versus sine tones and other first names. Latencies and amplitudes of N1 and P3 waves were compared., Results: Cortical responses were found in all MCS patients, and in 6 of 11 patients in VS. Healthy controls and MCS patients showed a progressive increase of P3 latency in relation to the level of stimulus complexity. No modulation of P3 latency was observed in the vegetative patients., Conclusions: These results suggest that the modulation of P3 latency related to stimulus complexity may represent an objective index of higher-order processing integration that predicts the recovery of consciousness from VS to MCS when clinical manifestations are inconsistent., Significance: Modulation of P3 latency related to stimulus complexity could provide valuable information about the cognitive capabilities of unresponsive patients., (Copyright © 2010 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

7,12-Dimethylbenzanthracene (DMBA) is an abundant environmental contaminant, which undergoes bioactivation, primarily by the CYP1 family, both in liver and extra-hepatic tissues. Dietary acetylsalicylic acid (ASA) has been recently reported to inhibit DMBA-mediated mammary tumour formation in rats. Chemopreventive substances may reduce the risk of developing cancer by decreasing metabolic enzymes responsible for generating reactive species (phase I enzymes) and/or increasing phase II enzymes that can deactivate radicals and electrophiles. To test these hypotheses, Sprague-Dawley female rats were orally administered ASA as lysine acetylsalicylate (50 mg per capita/day for 21 days in water), DMBA (10 mg per capita in olive oil on day 7, 14, and 21), ASA and DMBA in combination, and vehicles only, respectively. Six rats for each group were sacrificed on day 8, 15, and 22. The DMBA-mediated increase in hepatic CYP1A expression and related activities was not significantly affected by ASA, which, conversely, enhanced in a time-dependent manner the liver reduced glutathione content (up to 52%) and the activity of NAD(P)H-quinone oxidoreductase (up to 34%) in DMBA-treated rats. It is proposed that the positive modulation of the hepatic antioxidant systems by ASA may play a role in the chemoprevention of mammary tumourigenesis induced by DMBA in the female rat.

Objective: This study aimed to describe the use of the P300 event-related potential as a control signal in a brain computer interface (BCI) for healthy and paralysed participants., Methods: The experimental device used the P300 wave to control the movement of an object on a graphical interface. Visual stimuli, consisting of four arrows (up, right, down, left) were randomly presented in peripheral positions on the screen. Participants were instructed to recognize only the arrow indicating a specific direction for an object to move. P300 epochs, synchronized with the stimulus, were analyzed on-line via Independent Component Analysis (ICA) with subsequent feature extraction and classification by using a neural network., Results: We tested the reliability and the performance of the system in real-time. The system needed a short training period to allow task completion and reached good performance. Nonetheless, severely impaired patients had lower performance than healthy participants., Conclusions: The proposed system is effective for use with healthy participants, whereas further research is needed before it can be used with locked-in syndrome patients., Significance: The P300-based BCI described can reliably control, in 'real time', the motion of a cursor on a graphical interface, and no time-consuming training is needed in order to test possible applications for motor-impaired patients.

The effect of Dexamethasone (DEX) on cell division and macromolecular synthesis was investigated in a line (McCoy cells, A 9) of synovial fibroblast-like cells derived from human osteoarthritic joints. DEX markedly reduced the proliferation of McCoy cells in a time and dose-dependent manner. The maximal inhibition (45%) was found at 500 nM DEX 24 h after incubation and was accompanied by the appearance of giant macrophage-like cells. After DEX treatment cells showed increased content of DNA, proteins and RNA together with the reduction of [3H]-thymidine incorporation into the TCA-precipitable fraction.