Spatiotemporal Neurodynamics Underlying Internally and Externally Driven Temporal Prediction: A High Spatial Resolution ERP Study

Temporal prediction (TP) is a flexible and dynamic cognitive ability. Depending on the internal or external nature of information exploited to generate TP, distinct cognitive and brain mechanisms are engaged with the same final goal of reducing uncertainty about the future. In this study, we investigated the specific brain mechanisms involved in internally and externally driven TP. To this end, we employed an experimental paradigm purposely designed to elicit and compare externally and internally driven TP and a combined approach based on the application of a distributed source reconstruction modeling on a high spatial resolution electrophysiological data array. Specific spatiotemporal ERP signatures were identified, with significant modulation of contingent negative variation and frontal late sustained positivity in external and internal TP contexts, respectively. These different electrophysiological patterns were supported by the engagement of distinct neural networks, including a left sensorimotor and a prefrontal circuit for externally and internally driven TP, respectively

Transcranial Magnetic Stimulation and Neuroimaging Coregistration

The development of neuroimaging techniques is one of the most impressive advancements in neuroscience. The main reason for the widespread use of these instruments lies in their capacity to provide an accurate description of neural activity during a cognitive process or during rest. This important advancement is related to the possibility to selectively detect changes of neuronal activity in space and time by means of different biological markers. Specifically, functional magnetic resonance imaging (fMRI), positron emission tomography (PET), single-photon emission computed tomography (SPECT), and nearinfrared spectroscopy (NIRS) use metabolic markers of ongoing neuronal activity to provide an accurate description of the activation of specific brain areas with high spatial resolution. Similarly, electroencephalography (EEG) is able to detect electric markers of neuronal activity, providing an accurate description of brain activation with high temporal resolution. The application of these techniques during a cognitive task allows important inferences regarding the relation between the detected neural activity, the cognitive process involved in an ongoing task, and behaviour: this is known as a \u201ccorrelational approach\u201d

TMS-evoked long-lasting artefacts: A new adaptive algorithm for EEG signal correction

OBJECTIVE: During EEG the discharge of TMS generates a long-lasting decay artefact (DA) that makes the analysis of TMS-evoked potentials (TEPs) difficult. Our aim was twofold: (1) to describe how the DA affects the recorded EEG and (2) to develop a new adaptive detrend algorithm (ADA) able to correct the DA. METHODS: We performed two experiments testing 50 healthy volunteers. In experiment 1, we tested the efficacy of ADA by comparing it with two commonly-used independent component analysis (ICA) algorithms. In experiment 2, we further investigated the efficiency of ADA and the impact of the DA evoked from TMS over frontal, motor and parietal areas. RESULTS: Our results demonstrated that (1) the DA affected the EEG signal in the spatiotemporal domain; (2) ADA was able to completely remove the DA without affecting the TEP waveforms; (3). ICA corrections produced significant changes in peak-to-peak TEP amplitude. CONCLUSIONS: ADA is a reliable solution for the DA correction, especially considering that (1) it does not affect physiological responses; (2) it is completely data-driven and (3) its effectiveness does not depend on the characteristics of the artefact and on the number of recording electrodes. SIGNIFICANCE: We proposed a new reliable algorithm of correction for long-lasting TMS-EEG artifacts

Transcranial Magnetic Stimulation Trains at 1 Hz Frequency of the Right Posterior Parietal Cortex Facilitate Recognition Memory

Neuroimaging, neuropsychological, and brain stimulation studies have led to contrasting findings regarding the potential roles of the lateral parietal lobe in episodic memory. Studies using brain stimulation methods reported in the literature do not offer unequivocal findings on the interactions with stimulation location (left vs. right hemisphere) or timing of the stimulation (encoding vs. retrieval). To address these issues, active and sham 1 Hz repetitive transcranial magnetic stimulation (rTMS) trains of 600 stimuli were applied over the right or left posterior parietal cortex (PPC) before the encoding or before the retrieval phase of a recognition memory task of unknown faces in a group of 40 healthy subjects. Active rTMS over the right but not the left PPC significantly improved non-verbal recognition memory performance without any significant modulation of speed of response when applied before the retrieval phase. In contrast, rTMS over the right or the left PPC before the encoding phase did not modulate memory performance. Our results support the hypothesis that the PPC plays a role in episodic memory retrieval that appears to be dependent on both the hemispheric lateralization and the timing of the stimulation (encoding vs. retrieval)

Young adult obese subjects with and without insulin resistance: what is the role of chronic inflammation and how to weigh it non-invasively?

<p>Abstract</p> <p>Background</p> <p>Obesity is a leading risk factor for metabolic syndrome whose further expression is non-alcoholic fatty liver disease. Metabolic syndrome is associated with a proinflammatory state that contributes to insulin resistance. Finally, a "metabolically benign obesity" that is not accompanied by insulin resistance has recently been postulated to exist.</p> <p>Aim</p> <p>To find whether any inflammation markers were independently associated with the presence of insulin resistance, evaluating specific anthropometric, ultrasonographic and laboratory parameters in a population of young adult obese subjects.</p> <p>Methods</p> <p>Of forty two young individuals, divided into two groups (with or without insulin resistance), were studied serum C-reactive protein and fibrinogen as indexes of chronic pro-inflammatory status. Body mass index, waist circumference and metabolic syndrome presence were assessed as part of the metabolic evaluation. Ultrasonography weighted visceral and subcutaneous abdominal fat thickness, spleen size as longitudinal diameter and liver hyperechogenicity.</p> <p>Results and Discussion</p> <p>Serum C-reactive protein and fibrinogen as well as spleen longitudinal diameter were significantly increased in the obese young with insulin resistance compared to non-insulin resistance group. Insulin resistance was significantly associated with hepatic steatosis score at sonography (r = 0.33, P = 0.03), spleen longitudinal diameter (r = 0.35, P = 0.02) and C-reactive protein (r = 0.38, P = 0.01), but not with body mass index, visceral or subcutaneous abdominal adipose tissue, waist circumference and fibrinogen (P = 0.18, 0.46, 0.33, 0.37 and 0.4, respectively). Steatosis score at sonography was well associated with spleen volume (rho = 0.40, P = 0.01) and C-reactive protein levels (rho = 0.49, P = 0.002). Metabolic syndrome was much more frequent in obese patients with insulin resistance. These findings show that in young adults the only abdominal adiposity without insulin resistance, plays a scarce role in determining hepatic steatosis as well as metabolic syndrome.</p> <p>Conclusion</p> <p>Increases in spleen size and CRP levels represent a reliable tool in diagnosing insulin resistance.</p

ClearPath-assisted underwater endoscopic mucosal resection of a laterally spreading tumor of the colon

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Collaborative Interlaboratory Studies for the Validation of ELISA Methods for the Detection of Allergenic Fining Agents Used in Wine According to the Criteria of OIV Resolution 427–2010 Modified by OIV–Comex 502–2012

The clarification or fining of wine removes undesired substances (mainly proteins, phenols, and tannins), which would roil the wine and cause bitterness and astringency. A common fining agent, egg white, can be directly added to wine through the inlet of a circulating pump, but more typically egg white comes as commercial preparation in powdered form (commercially named egg albumin). Skimmed milk or more frequently purified caseinates are used to remove bitterness and hardness of white wine and sherry. Both egg white and caseinates are fining agents with optimal enological properties, but their residues could represent a risk for subjects suffering from food allergy. The rules for allergen labeling were detailed in Directives 2003/89/EC, and Directive 2005/26/EC established a list of food ingredients provisionally excluded from labeling, that included wine fining agents. Extended till June 2012, wine labeling exemption can be now maintained only if (1) egg and milk derivatives are not used and cross-contamination is under control; and (2) wine clarified with such products is negative for the presence of residues using techniques with detection and quantification limits of 0.25 and 0.5 ppm, respectively. Analytical requirements were defined in the OIV resolution 427–2010 (OIV 2010) modified by OIV/COMEX 502–2012 (OIV 2012). On the basis of a previous experience, an interlaboratory collaborative trial was organized to validate a commercial ELISA kit designed to measure allergenic residues in red wine fined with egg white proteins. In the meantime, the performance of the commercial caseinate ELISA kit for white wine was rechecked according to the new limit of detection and limit of quantification values, recommended by OIV in 2012. The collaborative interlaboratory studies showed that both ELISA kits had good reproducibility, repeatability, and robustness in detecting residues of allergenic fining agents in wine, in good agreement with the requirements of the OIV resolution 427–2010 modified by OIV/COMEX 502–2012

PCDH19 mutations in female patients from Southern Italy

AbstractPurposeMutations in PCDH19, encoding protocadherin 19 on chromosome X, cause familial epilepsy and mental retardation limited to females or Dravet-like syndrome. We wished to explore the causative role of PCDH19 gene (Xq22) in female patients with epilepsy, from Southern Italy.MethodsDirect sequencing of PCDH19 gene was conducted in 31 unrelated female patients with early onset (<1 year of age) epilepsy and a wide spectrum of phenotypes including febrile seizures, focal and generalized forms, with either sporadic or familial distribution.ResultsWe identified two de novo heterozygous novel mutations of PCDH19 gene (p.Arg550Pro, Ile508ProfsX59) in two of 31 unrelated female patients. We also identified a novel silent mutation p.Ser856=.ConclusionsThe present findings confirm that PCDH19 is a major causative gene for infantile onset familial or sporadic epilepsy in female patients with or without mental retardation

Long-term Memory of Sensory Experiences from the First Pregnancy, its Peri-partum and Post-partum in Women with Autism Spectrum Disorders without Intellectual Disabilities: A Retrospective Study

Purpose: To explore the recalled experience of pregnancy and motherhood in women diagnosed with Autism Spectrum Disorders (ASD) without intellectual disabilities, focusing on sensory perceptions and mood. Methods: We retrospectively evaluated, through an ad-hoc structured interview, the sensory sensitivity during the pre-partum, the peri-partum, and the post-partum of thirty-three mothers with ASD and thirty-two neurotypical mothers. Participants also underwent a psychometric assessment about autistic traits, general sensory sensitivity, and post-partum depressive symptomatology. Results: Mothers with ASD recalled a higher sensitivity than the comparison group across the three time-points; however, during the peri-partum their recalled hypersensitivity decreases, and in the post-partum it returned as high as before childbirth. The difference in the length of recall between groups did not statistically influence our results. Higher levels of autistic traits correlated with higher depressive post-partum symptomatology. Conclusions: Mothers with ASD seem to recall their experience of pregnancy, childbirth, and post-partum period differently from neurotypical mothers, particularly in terms of hypersensitivity. The correlation with depressive symptoms and the potential role of oxytocin and of long-term memory (encoding and recollection) are discussed. Further exploring these aspects might give fundamental hints to provide tailored support to mothers with ASD during pregnancy and motherhood