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Transcranial direct current stimulation (tDCS) has been widely used to modulate cognition and behavior. However, only a few studies have been probing the brain mechanism underlying the effects of tDCS on cognitive processing, especially throughout electrophysiological markers, such as the P3. This meta-analysis assessed the effects of tDCS in P3 amplitude and latency during an oddball, n-back, and Go/No-Go tasks, as well as during emotional processing. A total of 36 studies were identified, but only 23 were included in the quantitative analysis. The results show that the parietal P3 amplitude increased during oddball and n-back tasks, mostly after anodal stimulation over the left dorsolateral prefrontal cortex (p = 0.018, SMD = 0.4) and right inferior frontal gyrus (p

Anxiety disorders are highly prevalent and negatively impact daily functioning and quality of life. Transcranial direct current stimulation (tDCS) targeting the dorsolateral prefrontal cortex (dlPFC), especially in the right hemisphere impacts extinction learning; however, the underlying neural mechanisms are elusive. Therefore, we aimed to investigate the effects of cathodal tDCS stimulation to the right dlPFC on neural activity and connectivity patterns during delayed fear extinction in healthy participants.We conducted a two-day fear conditioning and extinction procedure. On the first day, we collected fear-related self-reports, clinical questionnaires, and skin conductance responses during fear acquisition. On the second day, participants in the tDCS group (Whole-brain searchlight classification during fear extinction showed higher classification accuracy of threat and safe cues in the left anterior dorsal and ventral insulae and hippocampus in the tDCS group than in the control group. Functional connectivity derived from the insula with the dlPFC, ventromedial prefrontal cortex, and inferior parietal lobule was increased after tDCS.tDCS over the right dlPFC may function as a primer for information exchange among distally connected areas, thereby increasing stimulus discrimination. The current study did not include a sham group, and one participant of the control group was not randomized. Therefore, to address potential allocation bias, findings should be confirmed in the future with a fully randomized and sham controlled study.

Attention and mind wandering are often seen as anticorrelated. However, both attention and mind wandering are multi-component processes, and their relationship may be more complex than previously thought. In this study, we tested the interference of different types of thoughts as measured by a Thought Identification Task TIT (on task thoughts, task related interference thoughts, external distractions, stimulus independent and task unrelated thoughts) on different components of the attention network system - ANT (alerting, orienting, executive). Results show that, during the ANT, individuals were predominantly involved in task related interference thoughts which, along with external distractors, significantly impaired their performance accuracy. However, mind wandering (i.e., stimulus independent and task unrelated thoughts) did not significantly interfere with accuracy in the ANT. No significant relationship was found between type of thoughts and alerting, orienting, or executive effects in the ANT. While task related interference thoughts and external distractions seemed to impair performance on the attention task, mind wandering was still compatible with satisfactory performance in the ANT. The present results confirmed the importance of differentiating type of "out of task" thoughts in studying the relationship between though distractors and attention., Oscar F. Goncalves was funded by the Brazilian National Counsel for Scientific and Technological Development (CNPq) as a Special Visiting Researcher of the Science Without Borders program (grant number: 401143/2014-7). This study was partially conducted at the Neuropsychophysiology Lab from the Psychology Research Centre (UID/PSI/01662/2013), University of Minho, and supported by the Portuguese Foundation for Science and Technology and the Portuguese Ministry of Science, Technology and Higher Education through national funds and co-financed by FEDER through COMPETE2020 under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007653). Paulo S Boggio is a CNPq researcher fellow (311641/2015-6) Gabriel Gaudencio Rego was supported by a PhD grant from Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP - 2015/18713-9). This work was also supported by the Portuguese Foundation for Science and Technology (FCT) and European Union (FSE-POPH) with two individual grants (SFRH/BPD/86041/2012 and SFRH/BPD/86027/2012)., info:eu-repo/semantics/publishedVersion

ResumoA rotura traumática da artéria vertebral é rara e no seu tratamento não é habitualmente possível preservar a sua permeabilidade. Apresentamos um caso de uma rotura submetida a tratamento endovascular com preservação do seu fluxo, com recurso a 2 stents cobertos, colocados em contexto de emergência.AbstractTraumatic rupture of the vertebral artery is a rare condition, treatment does not usually allow to preserve its permeability. We present a case of a endovascular treatment with preservation of the flow using two covered stents placed in emergency context.

Introduction: Prosthetic graft infection is a major complication of vascular surgery associated with high morbid-mortality rates. This retrospective non-randomized single center study evaluated our experience in the management of prosthetic vascular graft infections. Methods: We review the clinical files of patients who had vascular grafts implanted at our center between June 2007 and December 2011 and analysed the cases that developed Samson group 3, 4 and 5 infections until December 2012. Results: From June 2007 to December 2012, 18 consecutive patients (14 males, 4 females) with median age 70 years were admitted to our institution with the diagnosis of vascular graft infection accounting for an incidence of 3.8%. 50% of these infections were early infections and MRSA was the most prevalent pathogen. 44% of infections were due to infection of a femoro-popliteal bypass. Using Samson classification, 72% were group 4 and 5 infections. We performed graft preservation in one patient, graft excision without revascularization in 50% (nine) patients; Excision + insitu replacement in 39% (seven) patients; Excision + Extra-anatomic bypass in one patient. Our amputation rate was 55% and our related death rate was 16%. Conclusions: Our amputation and mortality rates are according the published reviews. Besides allowing recognition of our reality this offers the opportunity to review diagnosis and therapeutic issues in prosthetic vascular graft infections. Each situation needs to be individualized as there is no consensus nor guiding algorithms about what should be the best medical treatment Introdução: A infeção de enxertos protésicos vasculares é uma complicação grave da cirurgia vascular, cursando com altas taxas de morbimortalidade. Este estudo retrospetivo não randomizado, unicêntrico, avaliou a sua experiência na gestão de infeções de próteses vasculares. Métodos: Fez-se uma revisão dos processos clínicos das revascularizações protésicas vasculares realizadas no nosso centro entre junho de 2007 e dezembro de 2011 e selecionaram-se aquelas que desenvolveram infeções do grupo 3, 4 e 5 da classificação de Samson até dezembro de 2012. Resultados: Desde junho de 2007 a dezembro de 2012, 18 doentes (14 homens, 4 mulheres), com uma média de idade 70 anos, foram admitidos no nosso centro com o diagnóstico de infeções de próteses vasculares contribuindo para uma incidência de 3,8%. 50% das infeções foram precoces sendo o MRSA o patogéneo mais isolado. 44% das infeções deveram-se a infeção de conduto femoro-poplíteo. Usando a classificação de Samson, 72% foram infeções grupo 4 e 5. Realizámos preservação do enxerto num doente, excisão da prótese sem revascularização em 50% (nove) doentes; Excisão + substituição in situ em 39% (sete) doentes; Excisão + bypass extra-anatómico num doente. A nossa taxa de amputação foi de 55% e a nossa mortalidade relacionada foi de 16%. Conclusões: As taxas de amputação e mortalidade da série estão de acordo com as revisões publicadas previamente. Para além de permitir reconhecer a nossa realidade esta publicação oferece a oportunidade de rever o diagnóstico e questões terapêuticas relacionadas com infeções de enxertos vasculares protésicos. Cada situação deve ser individualizada, pois não há consenso nem protocolos estabelecidos sobre qual deve ser o tratamento de eleição.

Background Transcranial direct current stimulation (tDCS) has been studied as an add-on enhancer of extinction-based treatments for anxiety disorders. Previous studies have showed that although anodal tDCS enhances fear extinction it also leads to decreased stimuli discrimination and consequent generalization of the fear response. Here we aim to understand the impact of cathodal tDCS in the neural activity and connectivity patterns between the tDCS target site (the right dorsolateral prefrontal cortex; rDLPFC) and the extant fear network (the bilateral amygdala, bilateral hippocampus, bilateral insula and the ventro medial prefrontal cortex [vmPFC]). Additionally we aim to see if cathodal tDCS leads to adverse effects similar to the ones observed with anodal stimulation. Methods We used a three-day fear conditioning procedure (day 1–fear acquisition; day 2–20-min 1 mA cathodal tDCS (only tDCS group)+ fear extinction; day 3–fear re-instatement and fear re-extinction). Thirty-four female participants where randomly assigned to either the tDCS group (n = 16) or the control group (n = 18). In day 1 fear acquisition was confirmed by self-reported contingency ratings. In day 2 we observed the between group differences in neural activity and connectivity patterns during extinction. In day 3 we observed the self-reported measures of stimuli contingency and reaction times during an approach-avoidance task to tackle the unconscious, automatic and involuntary avoidance responses. Results Functional magnetic resonance imagining (fMRI) group-level maps showed that cathodal tDCS over rDLPFC effectively reduces the right hippocampus activity during the processing of the conditioned stimuli during extinction. Furthermore, group-level psychophysiological interaction analysis (PPI) showed that cathodal tDCS effectively interferes with the fear response neural network. In particular, during the processing of the conditioned stimuli in late extinction phase, tDCS inverts the positive coupling between the vmPFC and a broad range of prefrontal structures, in particular the right and left DLPFC that participate in the regulation of negative emotions. Finally, day 3 measures showed decreased contingency ratings for the neutral cue and increased stimuli discrimination in the tDCS group, suggesting that cathodal tDCS does not lead to increased generalization. Conclusion Our promising results show that 1 mA cathodal tDCS effectively interferes with a large-scale cortico-subcortical fear network during extinction, and confirms that tDCS is a potential add-on strategy to enhance extinction-based treatments. Future studies should observe the adequate parameters of stimulation for the simultaneous enhancement of extinction learning and increased stimuli discrimination.

Objectivos: A nefropatia induzida pelo contraste é a terceira causa de insuficiência renal aguda (IRA) hospitalar. Este estudo pretende determinar a incidência de IRA induzida pelo contraste durante procedimentos angiográficos. Materiais e métodos: Estudo prospectivo de 54 doentes internados no serviço para realização de procedimentos angiográficos de diagnóstico ou terapêutica. O contraste administrado foi o Ultravist 370®. Todos os doentes foram submetidos a profilaxia pré e pós-procedimento com bicarbonato sódico. Considerou-se IRA a elevação da creatinina em 0,5 mg/dl ou 25% do valor inicial, ou diminuição de 25% na taxa de filtração glomerular (TFG). Para o cálculo da TFG utilizou-se a fórmula de Cockcroft-Gault. A doença renal crónica (DRC) e insuficiência renal crónica (IRC) foram definidas conforme a TFG < 90 ml/min ou < 60 ml/min, respectivamente. Aplicou-se o teste não paramétrico Kruskal-Wallis para estudar a influência de possíveis factores de risco para a IRA. Considerou-se significância estatística p < 0,05. Resultados: Estudo com 47 doentes do sexo masculino (87%) e 7 do sexo feminino, com idade média de 62,3 ± 11,1 anos. Entre os factores considerados, observou-se hipertensão arterial (HTA) em 46 doentes (85,2%), DRC em 23 (43%), IRC em 10 (18,5%) e diabetes mellitus (DM) em 13 (24,1%). O volume de contraste utilizado foi em média 234,8 ml, com 209,7 ml nos procedimentos diagnósticos e 345,5 ml nos terapêuticos. A incidência de IRA foi 24,1% (13 casos) e 9,3% (5) utilizando a variação de creatinina e da TFG, respectivamente. A DM (p = 0,049) e IRC (p = 0,013) tiveram significância na indução de IRA. Uma reavalição posterior de 38 doentes evidenciou a irreversibilidade da insuficiência renal em 2 casos (5,2%). Conclusões: A incidência de nefropatia foi elevada apesar da profilaxia utilizada. A DM e IRC foram os factores predisponentes à IRA. A maior parte dos casos de IRA parece reversível. A utilização de contraste iso-osmolar e em menores quantidades poderá melhorar os resultados. Objectives: Contrast induced nephropathy is the third cause of hospital acute renal failure. This study aims to determine the incidence of acute renal failure (ARF) induced by contrast after angiographic procedures. Material and methods: Prospective study with 54 patients admitted to perform a diagnostic or therapeutic angiographic procedure. Ultravist 370® was used as contrast agent in all procedures. All patients were submitted to prophylaxis with sodium bicarbonate before and after procedure. ARF was considered if an increase in creatinine of more than 0.5 mg/dl or 25% of basal value, or a decrease of more than 25% in glomerular filtration rate (GFR) was observed. Cockcroft-Gault formula was used for GFR calculation. Chronic renal disease and chronic renal failure were defined as GFR

The objective of this study was to investigate the psycholinguistic abilities of children with Williams syndrome (WS) and typically developing children using the Illinois Test of Psycholinguistic Abilities (ITPA). Performance on the ITPA was analysed in a group with WS (N = 20, mean age = 8.5 years, SD = 1.62) and two typically developing groups, matched in mental (MA, N = 20, mean age = 4.92 years, SD = 1.14) and chronological age (CA, N = 19, mean age = 8.35 years, SD = 3.07). Overall, within-group analyses showed that individuals with WS displayed higher scalar scores on the visual reception and visual association subtests. When groups were compared, we observed inferior performance of the WS group on all ITPA subtests when compared with typically developing groups. Moreover, an interaction between reception and group was found, only the WS group demonstrated superior performance on the visual reception subtest when compared to the auditory reception subtest. Evidence from this study offers relevant contributions to the development of educational intervention programs for children with WS., Coordenação de Aperfeiçoamento de Pessoal de Nível Superior/CAPES (Processo: 1551/08-6) e Prope-UNESP-Santander and grant PIC/IC/83290/2007 from the Fundação para a Ciência e Tecnologia (FCT).

The present study analyses the modulatory effects of affective pictures in the early posterior negativity (EPN), the late positive potential (LPP) and the human startle response on both the peripheral (eye blink EMG) and central neurophysiological levels (Probe P3), during passive affective pictures viewing. The affective pictures categories were balanced in terms of valence (pleasant; unpleasant) and arousal (high; low). The data shows that EPN may be sensitive to specific stimulus characteristics (affective relevant pictures versus neutral pictures) associated with early stages of attentional processing. In later stages, the heightened attentional resource allocation aswell as themotivated significance of the affective stimuliwas found to elicit enhancedamplitudes of slow wave processes thought to be related to enhanced encoding, namely LPP,. Although pleasant low arousing pictureswere effective in engaging the resources involved in the slowwave processes, the highly arousing affective stimuli (pleasant and unpleasant) were found to produce the largest enhancement of the LPP, suggesting that high arousing stimulimay are associatedwith increasedmotivational significance. Additionally the response to high arousing stimulimay be suggestive of increasedmotivational attention, given the heightened attentional allocation, as expressed in the P3 probe, especially for the pleasant pictures. The hedonic valencemay then serve as amediator of the attentional inhibition to the affective priming, potentiating or inhibiting a shift towards defensive activation, as measured by the startle reflex., Portuguese Foundation for Science and Technology with individual grants (SFRH/BD/41484/2007 and SFRH/BD/64355/2009) and by the Spanish Xunta de Galicia – with FEDER funds – (DOG 233 — Resolution date: 2009 November 18th

Williams syndrome (WS) is a neurodevelopmental genetic disorder, often referred as being characterized by dissociation between verbal and non-verbal abilities, although the number of studies disputing this proposal is emerging. Indeed, although they have been traditionally reported as displaying increased speech fluency, this topic has not been fully addressed in research. In previous studies carried out with a small group of individuals with WS, we reported speech breakdowns during conversational and autobiographical narratives suggestive of language difficulties. In the current study, we characterized the speech fluency profile using an ecologically based measure – a narrative task (story generation) was collected from a group of individuals with WS (n = 30) and typically developing group (n = 39) matched in mental age. Oral narratives were elicited using a picture stimulus – the cookie theft picture from Boston Diagnosis Aphasia Test. All narratives were analyzed according to typology and frequency of fluency breakdowns (non-stuttered and stuttered disfluencies). Oral narratives in WS group differed from typically developing group, mainly due to a significant increase in the frequency of disfluencies, particularly in terms of hesitations, repetitions and pauses. This is the first evidence of disfluencies in WS using an ecologically based task (oral narrative task), suggesting that these speech disfluencies may represent a significant marker of language problems in WS., Conselho Nacional de Desenvolvimento Cientı´fico e Tecnolo´ gico (CNPq, Process GM/GD 141307/2006-4, MCT/CNPq 14/2009-474092/2009-7), Brazil, Coordenac¸a˜o de Aperfeic¸oamento de Pessoal de Nı´vel Superior (CAPES) - Programa de Doutorado no Paı´s com Esta´ gio no Exterior (PDEE, Process 1551/08-6), Brazil and Fundac¸a˜o para a Cieˆncia e Tecnologia (FCT, Process PTDC/PSI-PCL/115316/2009), Portugal

Williams syndrome (WS), a neurodevelopmental genetic disorder due to a microdeletion in chromosome 7, is described as displaying an intriguing socio-cognitive phenotype. Deficits in prosody production and comprehension have been consistently reported in behavioral studies. It remains, however, to be clarified the neurobiological processes underlying prosody processing in WS. This study aimed at characterizing the electrophysiological response to neutral, happy, and angry prosody in WS, and examining if this response was dependent on the semantic content of the utterance. A group of 12 participants (5 female and 7male), diagnosed with WS, with age range between 9 and 31 years, was compared with a group of typically developing participants, individually matched for chronological age, gender and laterality. After inspection of EEG artifacts, data from 9 participants with WS and 10 controls were included in ERP analyses. Participants were presented with neutral, positive and negative sentences, in two conditions: (1) with intelligible semantic and syntactic information; (2) with unintelligible semantic and syntactic information (‘pure prosody’ condition). They were asked to decide which emotion was underlying the auditory sentence. Atypical event-related potentials (ERP) components were related with prosodic processing (N100, P200, N300) in WS. In particular, reduced N100 was observed for prosody sentences with semantic content; more positive P200 for sentences with semantic content, in particular for happy and angry intonations; and reduced N300 for both types of sentence conditions. These findings suggest abnormalities in early auditory processing, indicating a bottomup contribution to the impairment in emotional prosody processing and comprehension. Also, at least for N100 and P200, they suggest the top-down contributions of semantic processes in the sensory processing of speech. This study showed, for the first time, that abnormalities in ERP measures of early auditory processing in WS are also present during the processing of emotional vocal information. This may represent a physiological signature of underlying impaired on-line language and socio-emotional processing., This work was supported by a Doctoral Grant (SFRH/BD/35882/2007) awarded to APP, as well as by the grant PIC/IC/83290/2007, Fundação para a Ciência e a Tecnologia (FCT)

Williams syndrome (WS), a genetic neurodevelopmental disorder due to microdeletion in chromosome 7, has been described as a syndrome with an intriguing socio-cognitive phenotype. Cognitively, the relative preservation of language and face processing abilities coexists with severe deficits in visual-spatial tasks, as well as in tasks involving abstract reasoning. However, in spite of early claims of the independence of language from general cognition in WS, a detailed investigation of language subcomponents has demonstrated several abnormalities in lexical-semantic processing. Nonetheless, the neurobiological processes underlying language processing in Williams syndrome remain to be clarified. The aim of this study was to examine the electrophysiological correlates of semantic processing in WS, taking typical development as a reference. A group of 12 individuals diagnosed with Williams syndrome, with age range between 9 and 31 years, was compared with a group of typically developing participants, individually matched in chronological age, gender and handedness. Participants were presented with sentences that ended with words incongruent (50%) with the previous sentence context or with words judged to be its best completion (50%), and they were asked to decide if the sentence made sense or not. Results in WS suggest atypical sensory ERP components (N100 and P200), preserved N400 amplitude, and abnormal P600 in WS, with the latter being related to late integration and re-analysis processes. These results may represent a physiological signature of underlying impaired on-line language processing in this disorder, This research was supported by a Doctoral Grant (SFRH/BD/35882/2007) awarded to the first author, as well as by the grant PIC/IC/83290/2007, both from FCT (Fundação para a Cieˆncia e a Tecnologia), in Portugal.