EEG correlation at a distance: a re-analysis of two studies using a machine learning approach

Background: In this paper, data from two studies relative to the relationship between the electroencephalogram (EEG) activities of two isolated and physically separated subjects were re-analyzed using machine-learning algorithms. The first dataset comprises the data of 25 pairs of participants where one member of each pair was stimulated with a visual and an auditory 500 Hz signals of 1 second duration. The second dataset consisted of the data of 20 pairs of participants where one member of each pair received visual and auditory stimulation lasting 1 second duration with on-off modulation at 10, 12, and 14 Hz. Methods and Results: Applying a 'linear discriminant classifier' to the first dataset, it was possible to correctly classify 50.74% of the EEG activity of non-stimulated participants, correlated to the remote sensorial stimulation of the distant partner. In the second dataset, the percentage of correctly classified EEG activity in the non-stimulated partners was 51.17%, 50.45% and 51.91%, respectively, for the 10, 12, and 14 Hz stimulations, with respect the condition of no stimulation in the distant partner. Conclusions: The analysis of EEG activity using machine-learning algorithms has produced advances in the study of the connection between the EEG activities of the stimulated partner and the isolated distant partner, opening new insight into the possibility to devise practical application for non-conventional "mental telecommunications" between physically and sensorially separated participants

A new method to detect event-related potentials based on Pearson's correlation

Event-related potentials (ERPs) are widely used in brain-computer interface applications and in neuroscience. Normal EEG activity is rich in background noise, and therefore, in order to detect ERPs, it is usually necessary to take the average from multiple trials to reduce the effects of this noise. The noise produced by EEG activity itself is not correlated with the ERP waveform and so, by calculating the average, the noise is decreased by a factor inversely proportional to the square root of N, where N is the number of averaged epochs. This is the easiest strategy currently used to detect ERPs, which is based on calculating the average of all ERP's waveform, these waveforms being time- and phase-locked. In this paper, a new method called GW6 is proposed, which calculates the ERP using a mathematical method based only on Pearson's correlation. The result is a graph with the same time resolution as the classical ERP and which shows only positive peaks representing the increase-in consonance with the stimuli-in EEG signal correlation over all channels. This new method is also useful for selectively identifying and highlighting some hidden components of the ERP response that are not phase-locked, and that are usually hidden in the standard and simple method based on the averaging of all the epochs. These hidden components seem to be caused by variations (between each successive stimulus) of the ERP's inherent phase latency period (jitter), although the same stimulus across all EEG channels produces a reasonably constant phase. For this reason, this new method could be very helpful to investigate these hidden components of the ERP response and to develop applications for scientific and medical purposes. Moreover, this new method is more resistant to EEG artifacts than the standard calculations of the average and could be very useful in research and neurology. The method we are proposing can be directly used in the form of a process written in the well-known Matlab programming language and can be easily and quickly written in any other software language

Fantastic animals as an experimental model to teach animal adaptation

Background: Science curricula and teachers should emphasize evolution in a mannercommensurate with its importance as a unifying concept in science. The concept of adaptationrepresents a first step to understand the results of natural selection. We settled an experimentalproject of alternative didactic to improve knowledge of organism adaptation. Students wereinvolved and stimulated in learning processes by creative activities. To set adaptation in a historicframe, fossil records as evidence of past life and evolution were considered.Results: The experimental project is schematized in nine phases: review of previous knowledge;lesson on fossils; lesson on fantastic animals; planning an imaginary world; creation of an imaginaryanimal; revision of the imaginary animals; adaptations of real animals; adaptations of fossil animals;and public exposition. A rubric to evaluate the student's performances is reported. The projectinvolved professors and students of the University of Modena and Reggio Emilia and of the "G.Marconi" Secondary School of First Degree (Modena, Italy).Conclusion: The educational objectives of the project are in line with the National Indications ofthe Italian Ministry of Public Instruction: knowledge of the characteristics of living beings, themeanings of the term "adaptation", the meaning of fossils, the definition of ecosystem, and theparticularity of the different biomes. At the end of the project, students will be able to graspparticular adaptations of real organisms and to deduce information about the environment in whichthe organism evolved. This project allows students to review previous knowledge and to form theirpersonalities

EEG correlates of social interaction at distance

This study investigated EEG correlates of social interaction at distance between twenty-five pairs of participants who were not connected by any traditional channels of communication. Each session involved the application of 128 stimulations separated by intervals of random duration ranging from 4 to 6 seconds. One of the pair received a one-second stimulation from a light signal produced by an arrangement of red LEDs, and a simultaneous 500 Hz sinusoidal audio signal of the same length. The other member of the pair sat in an isolated sound-proof room, such that any sensory interaction between the pair was impossible. An analysis of the Event-Related Potentials associated with sensory stimulation using traditional averaging methods showed a distinct peak at approximately 300 ms, but only in the EEG activity of subjects who were directly stimulated. However, when a new algorithm was applied to the EEG activity based on the correlation between signals from all active electrodes, a weak but robust response was also detected in the EEG activity of the passive member of the pair, particularly within 9 – 10 Hz in the Alpha range. Using the Bootstrap method and the Monte Carlo emulation, this signal was found to be statistically significant

Impaired testicular signaling of vitamin A and vitamin K contributes to the aberrant composition of the extracellular matrix in idiopathic germ cell aplasia

Objective: To study pathogenic features of the somatic testicular microenvironment associated with idiopathic germ cell aplasia. Design: Cross-sectional study. Setting: Tertiary referral center for reproductive medicine. Patient(s): Testicular specimens from men with idiopathic nonobstructive azoospermia (iNOA) prospectively submitted to microdissection testicular sperm extraction. Of 20 specimens used for histology, 10 were also available for proteomic analysis. Primary Sertoli cells with normal karyotype and phenotype were also used. Intervention(s): Patients with iNOA were dichotomized according to a positive versus negative sperm retrieval at microdissection testicular sperm extraction, and on the isolated extracellular matrix (ECM) the proteomic analysis was performed. Main Outcome Measure(s): Proteomic analysis of the ECM from testicular specimens with positive versus negative sperm retrieval. Gene ontology enrichment was used to identify upstream regulators based on the 11 deregulated ECM proteins, which were validated by immunohistochemistry and quantitative polymerase chain reaction. Continuous variables were expressed as medians and interquartile range. Result(s): Germ cell aplasia was characterized by an increased signaling of the retinoic acid in Sertoli cells and associated with decreased expression of the basal membrane markers nidogen-2 and heparan sulfate proteoglycan-2. Decreased levels of the interstitial matrisome-associated factor IX and its regulator VKORC1 were, instead, coupled with decreased signaling of vitamin K in Leydig cells. An altered expression of a further eight ECM proteins was also found, including laminin-4 and laminin-5. Peripheral levels of the two vitamins were within the reference range in the two cohorts of iNOA men. Conclusion(s): We identified the pathogenetic signature of the somatic human testicular microenvironment, providing two vitamin-related mechanistic insights related to the molecular determinants of the idiopathic germ cell aplasia

Mucinous Cystic Neoplasm of the Pancreas is Not an Aggressive Entity

Objective: Mucinous cystic neoplasms (MCNs) of the pancreas have often been confused with intraductal papillary mucinous neoplasms. We evaluated the clinicopathologic characteristics, prevalence of cancer, and prognosis of a large series of well-characterized MCNs in 2 tertiary centers. Methods: Analysis of 163 patients with resected MCNs, defined by the presence of ovarian stroma and lack of communication with the main pancreatic duct. Results: MCNs were seen mostly in women (95%) and in the distal pancreas (97%); 25% were incidentally discovered. Symptomatic patients typically had mild abdominal pain, but 9% presented with acute pancreatitis. One hundred eighteen patients (72%) had adenoma, 17 (10.5%) borderline tumors, 9 (5.5%) in situ carcinoma, and 19 (12%) invasive carcinoma. Patients with invasive carcinoma were significantly older than those with noninvasive neoplasms (55 vs. 44 years, P = 0.01). Findings associated with malignancy were presence of nodules (P = 0.0001) and diameter ≥60 mm (P = 0.0001). All neoplasms with cancer were either ≥40 mm in size or had nodules. There was no operative mortality and postoperative morbidity was 49%. Median follow-up was 57 months (range, 4 –233); only patients with invasive carcinoma had recurrence. The 5-year disease-specific survival for noninvasive MCNs was 100%, and for those with invasive cancer, 57%. Conclusions: This series, the largest with MCNs defined by ovarian stroma, shows a prevalence of cancer of only 17.5%. Patients with invasive carcinoma are older, suggesting progression from adenoma to carcinoma. Although resection should be considered for all cases, in low-risk MCNs (≤4 cm/no nodules), nonradical resections are appropriate

Anti-Mullerian Hormone-to-Testosterone Ratio is Predictive of Positive Sperm Retrieval in Men with Idiopathic Non-Obstructive Azoospermia

The lack of clinically-reliable biomarkers makes impossible to predict sperm retrieval outcomes at testicular sperm extraction (TESE) in men with non-obstructive azoospermia (NOA), resulting in up to 50% of unnecessary surgical interventions. Clinical data, hormonal profile and histological classification of testis parenchyma from 47 white-Caucasian idiopathic NOA (iNOA) men submitted to microdissection TESE (microTESE) were analyzed. Logistic regression analyses tested potential clinical predictors of positive sperm retrieval. The predictive accuracy of all variables was evaluated using the receiver operating characteristic-derived area under the curve, and the clinical net benefit estimated by a decision-curve analysis (DCA). Overall, 23 (49%) and 24 (51%) patients were classified as positive and negative sperm retrievals at microTESE. While circulating hormones associated to a condition of primary hypogonadism did not predict sperm retrieval, levels of anti-Mullerian hormone (AMH) and the ratio AMH-to-total Testosterone (AMH/tT) achieved independent predictor status for sperm retrieval at microTESE, with a predictive accuracy of 93% and 95%. Using cutoff values of <4.62 ng/ml for AMH and <1.02 for AMH/tT, positive sperm retrieval was predicted in all individuals, with 19 men out of 47 potentially spared from surgery. DCA findings demonstrated clinical net benefit using AMH and AMH/tT for patient selection at microTESE

Characterization of cytosolic proliferating cell nuclear antigen (PCNA) in neutrophils: antiapoptotic role of the monomer.

We have shown previously that PCNA, a nuclear factor involved in DNA replication and repair in proliferating cells, is localized exclusively in the cytoplasm of neutrophils, where it regulates their survival. Nuclear PCNA functions are tightly linked to its ring-shaped structure, which allows PCNA to bind to numerous partner proteins to orchestrate DNA-related processes. We have shown that only monomeric PCNA can expose its NES to be relocalized from nucleus to cytosol during granulocyte differentiation. This study tested the hypothesis that monomeric PCNA could have a biological role in neutrophils. With the use of a combination of cross-linking and gel-filtration experiments, trimeric and monomeric PCNAs were detected in neutrophil cytosol. The promyelocytic cell line PLB985 was next stably transfected to express the monomeric PCNAY114A mutant to examine its function compared with the WT trimeric PCNA. Monomeric PCNAY114A mutant potentiated DMF-induced differentiation, as evidenced by an increased percentage of CD11b- and gp91phox-positive PLB985PCNAY114A cells and by an increased, opsonized zymosan-triggered NADPH oxidase activity compared with PLB985PCNA or PLB985 cells overexpressing WT PCNA or the empty plasmid, respectively. Regarding antiapoptotic activity, DMF-differentiated PLB985 cells overexpressing WT or the monomeric PCNAY114A mutant displayed a similar antiapoptotic activity following treatment with gliotoxin or TRAIL compared with PLB985. The molecular basis through which cytoplasmic PCNA exerts its antiapoptotic activity in mature neutrophils may, at least in part, be independent of the trimeric conformation