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Chromosome numbers are given for 2 Centaurea species endemic to Sicily. For both studied taxa, Centaurea valdemonensis and C. virescens, the somatic chromosome number, found on material from their loci classici, is diploid (2n = 18).

Objective: The purpose of this study is to obtain/create/develop an automatized procedure to personalize electrodes for transcranial electrical stimulation (tES) using individual brain magnetic resonance images (MRI). The electrode thus matches the individual cortical folding of the whole body bilateral primary somatosensory cortex (S1RePE). The selection of a specific regional brain target is a crucial part of any neuromodulation intervention, which is a promising tool in the enhancement of recovery from neurological or psychiatric damages. Methods: By employing highly standardized MRI analysis software, we developed an automatized procedure for S1RePE shaping. We applied this procedure in 14 healthy people and assessed the accuracy of the procedure by comparing the automatized S1RePE with that which was manually traced in individual brain 3D MRI. Results: In all subjects, the automatic and manual procedures were highly consistent, with mean Euclidean distance of 2.3 mm and mean intra-class correlation 0.995. Conclusion: We successfully developed an automatized procedure, which is simpler, more replicable and requires less time than the procedure used up to this point in shaping S1RePE. Significance: We provide an automatic procedure using the individual cerebral MRI exam to shape a tES personalized electrode that matches the individual cortical folding. This automatic procedure can be adapted to any cortical region in the case that a specific cortical sulcus demarcates it.

Recently, a procedure to personalize the electrode to stimulate specific cortical regions by transcranial electric stimulations (tES) has been proposed. Results of these studies documented that the cortical excitability was differently modulated depending on where the personalized electrode was positioned, thus refining previous evidences that it is possible to focus the effects of tES by properly shaping and positioning the electrodes to target a region of interest of the cerebral cortex. This study aims to assess, through computational modelling techniques, the distribution of the electric field (E) induced by tES via the regional personalized (RePE) and the non-personalized (ReNPE) electrode.

Introduction: The brain is a connected network, requiring complex-system measures to describe its organization principles [1,2]. Here, we aim at testing whether the normalized compression distance (NCD) [3] is a suitable quantifier of the functional connectivity between cortical regions. This new measure estimates the information shared by two signals comparing the compression length of one signal given the other, without requiring any representation of the single in harmonics or selecting a specific time window where to compare the two signals. We show that this new measure is a good candidate to estimate the inter-nodes connectivity since it displays features 'expected' for brain connectivity, i.e. it is maximal between homologous cortical areas, it is higher for dominant cortical areas, it depends on age. In order to do it we estimated the NCD between functionally homologous primary somatosensory areas (S1) activities, testing the above-mentioned properties. Methods: Twenty-eight healthy, right-handed volunteers participated in the study. We recorded brain magnetic activity in the left and right Rolandic regions by a 28-channel magnetoencephalographic (MEG) system. We recorded rest activity for 3 min in each hemisphere. MEG activity was also collected during the electrical stimulation of the contralateral median nerve at the wrist delivered via surface disks. Elicited electric pulses were 0.2 ms in duration and 631 ms of inter-stimulus interval. Left and right median nerves were separately stimulated, totaling about 200 artifact-free trials for each. We used the Functional Source Separation (FSS) [4,5] algorithm to identify functionally homologous areas in the two hemispheres devoted to the somatosensory hand representation (FS_S1). Therefore, we calculated NCD between the left and right FS_S1s at rest. NCD is a parameter-free, quasi-universal similarity measure, computed from the lengths of compressed data files, singly and in pairwise concatenation. In other terms, NCD defines that two objects are similar if we can significantly "compress" one given the information of the other. We compared the similarity between the left and right homologous areas in single subjects and across the whole group. In particular, we compared the similarity of the activities in the two hemispheres of the same subject, with that in the same or in the opposite hemisphere of different subjects in the group of people. Results: NCD was minimal (maximal functional connectivity) between the neuronal activities of hemispheric functionally homologous areas in the same subject, i.e the NCD between the left and right FS_S1 of the same person was smaller than across different subjects (p

The brain is a connected network, requiring complex-system measures to describe its organization principles. The normalized compression distance (NCD) [1] is a parameter -free, quasi universal similarity measure that estimates the information shared by two signals comparing the compression length of one signal given the other. Here, we aim at testing whether this new measure is a suitable quantifier of the functional connectivity between cortical regions. In particular, we tested whether NCD between homologous hemispheric regions is smaller (higher connectivity) in the same person than across different people, if it is smaller in the dominant hemisphere and if it depends on age. We used the Functional Source Separation (FSS) [2] algorithm on magnetoencephalographic (MEG) data in order to identify functionally homologous areas in the two hemispheres devoted to the somatosensory contra-lateral hand representation (FS_S1) in 28 healthy people. Therefore, we calculated NCD between the left and right FS_S1s activities at rest. We found that NCD 1) between left and right FS_S1s of the same person was smaller than across different people (p

Introduction: Recently we developed a new procedure to personal- ize the electrode to selectively stimulate specific cortical regions by transcranial electric stimulations (tES).This study aims to assess by computational approach the distribution of the intra-cerebral elec- tric field induced by tES through the personalized in comparison with a non-personalized electrode in human models. Methods: We used two realistic human models and 40 tissue con- ductivities.We targeted bilateral primary motor (M1) and somatosensory cortex (S1) alternatively with the personalized and non-personalized electrode, with the reference on the occipital area. We estimated the distribution of the electric field across the brain structures. Results: The personalized electrode was able to modulate more deeply and strongly the area of the central sulcus than the non- personalized one. This trend was more evident in the regions along the central sulcus more far away from Cz, where the two electrodes are less overlapped and for both targets (M1 and S1). Moreover, the personalized electrode used to target S1 more selectively modulated the postcentral gyrus, whereas the personalized electrode used to target M1 broadened its effects over both the pre and postcentral gyrus. Discussions: This work strengthens the notion that tES can be focused by properly shaping and positioning the stimulating elec- trodes according to the target regions. doi:10.1016/j.clinph.2015.11.419

There is a lack of information on the characteristics of patients with chronic hepatitis C virus infection (HCV) who fail to respond to antiviral treatment. We studied HCV-positive subjects with chronic liver diseases treated with pegylated-interferon (PEG-IFN) and ribavirin (RBV) who failed to clear HCV in routine clinical practice. A total of 2150 consecutive adult patients treated with PEG-IFN plus RBV therapy in 46 Italian centres between 1 July 2004, and 30 June 2005, were studied. Of the 2150 patients, 923 (42.9%) (M/F 585/335, mean age 54.8 years) failed to achieve a serum HCV-RNA clearance. Of these 923 patients, 429 (46.5%) were nonresponders, 298 (32.3%) relapsers, 168 (18.2%) drop-outs for noncompliance or adverse events and 28 (3.0%) were lost during follow-up. Overall, 642 (70.6%) patients received adequate therapy (defined as more than 80% of the drug doses for >80% of the time). Genotypes 1-4 were observed in 76.9% of cases; genotypes 2-3 in 21.2% and mixed in 1.9%, respectively. Multiple logistic regression analysis identified genotypes 1 and 4 as the sole independent predictors of the likelihood of nonresponse to therapy compared with relapse (OR: 4.38; 95% CI = 2.28-8.4). Age older than 65 years was the sole independent factor associated with no adherence to therapy (OR: 2.22; 95% CI = 1.36-3.62). Patients who fail to respond to treatment are a nonhomogeneous population with different features, and the sole factor that discriminates nonresponse from relapse is the distribution of genotypes 1-4. Co-morbidities are unable to determine the type of treatment failure and inadequate adherence to therapy mostly affects patients older than 65 years of age. © 2009 Blackwell Publishing Ltd.

OBJECTIVE: Evaluation of the interaction between alcohol intake and cofactors [hepatitis B virus (HBV), hepatitis C virus (HCV), body mass index] and coffee consumption on the risk of cirrhosis. DESIGN: Seven hundred and forty-nine consecutive patients with chronic liver disease referring to units for liver or alcohol diseases in Italy during a 6-months period. Teetotalers were excluded. The odds ratios (OR) for cirrhosis were evaluated using chronic hepatitis cases as the control group. RESULTS: An alcohol intake of more than 3 units/day resulted associated with the likelihood of cirrhosis both in males (OR 4.3; 95% CI=2.5-7.3) and in females (OR 5.7; 95% CI=2.3-14.5). A multiplicative interaction on the risk of cirrhosis between risky alcohol intake and HBsAg or HCV-Ab/HCV-RNA positivity was observed. A reduction of cirrhosis risk was observed in subjects consuming more than 3 alcohol units/day with increasing coffee intake. The OR for the association with cirrhosis decreased from 2.3 (95% CI=1.2-4.4) in subjects drinking 0-2 cups of coffee/day to 1.4 (95% CI=0.6-3.6) in those drinking more than 2 cups/day. CONCLUSIONS: In subjects with an alcohol intake >3 units/day the coexistence of HBV or HCV multiplies the risk of cirrhosis. Coffee represents a modulator of alcoholic cirrhosis risk.