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Introduction: The autonomic nervous system (ANS) is likely to play a role in some of the etiologic factors of nocturnal enuresis (NE), such as nocturnal polyuria, disorder of arousal, or detrusor hyperactivity. The aim of this study was to evaluate ANS functions in children with NE. Methods: Twenty-two children with NE and 20 healthy children were allocated for this study. In electrophysiologic evaluation, palmar and plantar sympathetic skin responses (SSR) and RR interval variation (RRIV) were carried out in both groups. The minimum and mean latencies of SSRs, maximum and mean amplitudes of SSRs, RRIV at rest and during deep breathing, the difference between resting and deep breathing RRIVs, ratio of deep breathing to resting RRIV, and maximum to minimum RR interval at rest and during deep breathing were calculated. For group comparisons; Mann-Whitney U test was used for abnormally distributed data, independent t-test was used for normally distributed data for continuous variables. Results: The mean ages were 10.75±3.49 and 10.91±3.10 years for patients and controls, respectively. There was no significant difference between the groups in terms of age and sex (p>0.05). Palmar and plantar SSRs could be obtained in all subjects in NE and control groups. There was no significant difference between the groups in SSR or RRIV parameters (p>0.05). Discussion and Conclusion: This result suggests that ANS system functions may be normal in enuretic group when not classified for the etiologies. However, the effect of the ANS may be more evident for one of the above-mentioned etiologic factors. Therefore, assessing ANS functions in patients classified according to the etiologies may be more useful to demonstrate the link between ANS dysfunction and NE. [ABSTRACT FROM AUTHOR]

Background: Guillain-Barré syndrome (GBS) patients who present very early (< 4 days) to health-care services generally have severe clinical forms due to rapid progression. Little information exists on the clinical and short-term functional prognosis in patients with very-early GBS (VEGBS). Methods: A prospective cohort study was conducted. We performed Kaplan-- Meier survival analysis to observe the recovery of independent gait between groups, where a log-rank value < 0.05 was considered significant. All statistical analyzes were performed using SPSS version 22. Results: Ninety-nine patients were included in the study. Mean age was 46.7 ± 16.7 years, 61.9% were male. Regarding nerve conduction studies, the most frequent electrophysiological variants in the very early-onset GBS group were axonal (38.7%). Twenty-three percent were classified as equivocal. In the GBS group > 4 days, the most frequent electrophysiological variant was acute inflammatory demyelinating polyneuropathy (52.1%). Conclusion: Patients with VEGBS do not present different clinical characteristics, nor severity or poor short-term outcome in our population compared to different GBS presentations. Only mechanical ventilation requirement and distal compound muscle action potential reduction are associated with poor outcome in this subset of patients. [ABSTRACT FROM AUTHOR]

Background: Carpal tunnel release is recommended when patients have positive electrophysiologic test and their symptoms are not resolved in spite of conservative treatment. However, only some of them eventually undergo the surgery. The purposes of this study, therefore, were to evaluate the rate of carpal tunnel release performed among the patients with positive electrophysiologic test, and to identify which factors were associated with the rate of the surgery. Methods: Subjects of this study were 865 wrists of 508 patients (90 males and 418 females) who were diagnosed as carpal tunnel syndrome between January 2013 and December 2016. The diagnosis of carpal tunnel syndrome was confirmed by electrophysiologic test, and only the patients who were followed up for more than 1 year were enrolled in this study. The average age at the time of the electrophysiologic test performed was 61.4 years, and the severity of carpal tunnel syndrome was evaluated according to the Bland scale (Gr 1–6) based on the electrophysiologic test. Whether or not the patients received carpal tunnel release was evaluated at the last follow-up visit. Results: Among the 865 wrists, carpal tunnel release was performed on 528 wrists (61%). Rate of the surgery performed significantly increased in patients with more severe grades on electrophyisiologic test. More patients in female (63.3%) than in male (50.3%) and more patients with age under 60 (67.5%) than age over 60 (57.1%) received the surgery. However, there was no significant difference in the rate of carpal tunnel release according to the bilaterality or dominant hand. Conclusions: The rate of carpal tunnel release among the patients diagnosed and confirmed as carpal tunnel syndrome was not higher than we expected. We should also pay more attention to the patients who did not undergo carpal tunnel release and investigate the reasons why those patients did not undergo surgery. [ABSTRACT FROM AUTHOR]

When animals move or forage in groups, collective behaviors arise from independent decisions that individuals make based on limited information about the environment. In decentralized systems in which individuals use local cues to decide how to allocate their time amongst multiple tasks, a “global” signal detectable over large distances by all members of the group could have a profound effect on task allocation and coordination. Honeybees provide a unique opportunity to study how information transfer modulates behavior because they produce pheromones that can regulate the actions of thousands of individuals in a colony. We used electrophysiological and behavioral assays to compare the transmission modes of 2 larval pheromones to test the hypothesis that larval pheromones can act as “global” signals by rapidly regulating behavior throughout a colony without direct physical interactions between individuals. By studying mechanisms of pheromone transmission at the individual and colony level, we provide evidence that larval pheromones act as direct rapid and powerful regulators of behavior, even among individuals too far away from each other to use visual or tactile cues. Therefore, our results suggest that in some cases, global signals can be important regulators of collective behavior. [ABSTRACT FROM AUTHOR]

Background: Rheumatoid arthritis is a systemic rheumatic disease characterized by symmetrical, often erosive and deforming polyarthritis. Extra-articular manifestations occur in 10-20% of patients, especially those with high titers of rheumatoid factor. Neuromuscular ultrasound is useful for the work up of posterior tibial nerve neuropathy. Diagnosis of posterior tibial neuropathy is based on a combination of characteristic symptoms and electrophysiological abnormalities. Recently, neuromuscular ultrasound has become an attractive complement to electrodiagnostic (EDX) studies in the evaluation of peripheral nerves. Aim of the Work: To evaluate neuromuscular ultrasound versus electrophysiological studies in assessment of posterior tibial nerve neuropathy in rheumatoid arthritis patients. Patients and Methods: The subjects included in our study functionally were divided into two groups. Group (A): Thirty Egyptian patients with Rheumatoid Arthritis (RA), all fulfilled the American College of Rheumatology (ACR) 2010 criteria for diagnosis of RA and ACR criteria for classification of rheumatoid arthritis (1987). All were over the age of sixteen at time of diagnosis. They were recruited from Physical Medicine, Rheumatology and Rehabilitation Department at Al-Hussein and Sayed Galal University Hospitals during the period from November 2017 to April 2018. They were complaining of burning pain or paresthesia on the plantar aspect of the foot and toes. Group (B): Thirty healthy individuals, age and sex matched, were used as a control group after an informed consent from all subjects. Results: Neuromuscular ultrasound had a complementary role in the diagnosis of posterior tibial nerve neuropathy. The combined use of electrophysiology with neuromuscular ultrasonography further confirmed the diagnosis of posterior tibial nerve neuropathy. Conclusion: Neuromuscular ultrasound became an attractive complement to electrodiagnostic (EDX) studies in the evaluation of posterior tibial nerve neuropathy. [ABSTRACT FROM AUTHOR]

Epilepsy is one of the most common chronic neurological diseases, and its pharmacological treatment holds great importance for both physicians and national authorities, especially considering the high proportion of drug-resistant patients (about 30%). Lacosamide (LCM) is an effective and well-tolerated new-generation antiepileptic drug (AED), currently licensed as add-on therapy for partial-onset seizures. However, LCM mechanism of action is still a matter of debate, although its effect on the voltage sensitive sodium channels is by far the most recognized. This study aimed to retrospectively analyze a cohort of 157 drug-resistant patients treated with LCM to describe the most common and effective therapeutic combinations and to investigate if the LCM can affect also GABA A -mediated neurotransmission as previously shown for levetiracetam (LEV). In our cohort, LEV resulted the compound most frequently associated with LCM in the responder subgroup. We therefore translated this clinical observation into the laboratory bench by taking advantage of the technique of “membrane micro-transplantation” in Xenopus oocytes and electrophysiological approaches to study human GABA A -evoked currents. In cortical brain tissues from refractory epileptic patients, we found that LCM reduces the use-dependent GABA impairment (i.e., “rundown”) that it is considered one of the specific hallmarks of drug-resistant epilepsies. Notably, in line with our clinical observations, we found that the co-treatment with subthreshold concentrations of LCM and LEV, which had no effect on GABA A currents on their own, reduced GABA impairment in drug-resistant epileptic patients, and this effect was blocked by PKC inhibitors. Our findings demonstrate, for the first time, that LCM targets GABA A receptors and that it can act synergistically with LEV, improving the GABAergic function. This novel mechanism might contribute to explain the clinical efficacy of LCM-LEV combination in several refractory epileptic patients. [ABSTRACT FROM AUTHOR]

Objectives: High‐resolution ultrasonography (US) can play an important role in studying nerves, as it has several advantages. Entrapments of distal tibial nerve branches can be mapped out or diagnosed with selective anesthetic blocks, and US can guide therapeutic procedures, such as radiofrequency ablation and selective infiltrations of specific nerve branches. The aim of this study was to verify that US is an effective method for accurately locating the posterior tibial nerve and its terminal branches, such as the medial calcaneal branch, the first calcaneal branch, and the medial and lateral plantar nerves. Methods: In this study, we analyzed the correlation between US mapping and real anatomy after cadaveric dissection, assessing the distribution and variability of the tibial nerve and its terminal branches. We used 12 fresh anatomic specimens of the foot and ankle, including the calf. A high‐resolution US study of the tibial nerve and its branches was performed. Results: The results of the US studies of the anatomic specimens were drawn as paper diagrams and in data collection tables. Both were completed twice per anatomic specimen, first using the results of the US study and second using the results from dissection of the anatomic specimens; this approach enabled us to compare the results and verify whether the US study and the dissection correlated on the topography of the tibial nerve and its terminal branches. We found almost total agreement between the US and dissection results, with no significant differences between the evaluations. Conclusions: On the basis of this work, we can conclude that high‐resolution US is almost 100% effective as a tool for identifying the tibial nerve and its branches, enabling the specialist to make diagnoses or perform selective treatments on each nerve branch and even to design surgical interventions by observing the patient's anatomy before performing the dissection [ABSTRACT FROM AUTHOR]

Fragile X syndrome (FXS) is the leading cause of inherited intellectual disability, with additional symptoms including attention deficit and hyperactivity, anxiety, impulsivity, and repetitive movements or actions. The majority of FXS cases are attributed to a CGG expansion that leads to transcriptional silencing and diminished expression of fragile X mental retardation protein (FMRP). FMRP, an RNA binding protein, regulates the synthesis of dendritically-translated mRNAs by stalling ribosomal translation. Loss of FMRP leads to increased translation of some of these mRNAs, including the CNS-specific tyrosine phosphatase STEP (STriatal-Enriched protein tyrosine Phosphatase). Genetic reduction of STEP in Fmr1 KO mice have diminished audiogenic seizures and a reversal of social and non-social anxiety-related abnormalities. This study investigates whether a newly discovered STEP inhibitor (TC-2153) could attenuate the behavioral and synaptic abnormalities in Fmr1 KO mice. TC-2153 reversed audiogenic seizure incidences, reduced hyperactivity, normalized anxiety states, and increased sociability in Fmr1 KO mice. Moreover, TC-2153 reduced dendritic spine density and improved synaptic aberrations in Fmr1 KO neuronal cultures as well as in vivo . TC-2153 also reversed the mGluR-mediated exaggerated LTD in brain slices derived from Fmr1 KO mice. These studies suggest that STEP inhibition may have therapeutic benefit in FXS. [ABSTRACT FROM AUTHOR]

The rapid extraction of facial identity and emotional expressions is critical for adapted social interactions. These biologically relevant abilities have been associated with early neural responses on the face sensitive N170 component. However, whether all facial expressions uniformly modulate the N170, and whether this effect occurs only when emotion categorization is task-relevant, is still unclear. To clarify this issue, we recorded high-resolution electrophysiological signals while 22 observers perceived the six basic expressions plus neutral. We used a repetition suppression paradigm, with an adaptor followed by a target face displaying the same identity and expression (trials of interest). We also included catch trials to which participants had to react, by varying identity (identity-task), expression (expression-task) or both (dual-task) on the target face. We extracted single-trial Repetition Suppression (stRS) responses using a data-driven spatiotemporal approach with a robust hierarchical linear model to isolate adaptation effects on the trials of interest. Regardless of the task, fear was the only expression modulating the N170, eliciting the strongest stRS responses. This observation was corroborated by distinct behavioral performance during the catch trials for this facial expression. Altogether, our data reinforce the view that fear elicits distinct neural processes in the brain, enhancing attention and facilitating the early coding of faces. [ABSTRACT FROM AUTHOR]

Objective The objective of this study was to determine the predictors of outcomes and refractoriness in status epilepticus (SE). Methods This is a prospective study of 59 adult patients with SE who were admitted to the Emergency Department between February 2012 and December 2013. The effects of clinical, demographic, and electrophysiologic features of patients with SE were evaluated. To evaluate outcome in SE, STESS, mSTESS, and EMSE scales were used. Results Logistic regression analysis showed that being aged ≥ 65 years (p = 0.02, OR: 17.68, 95% CI: [1.6–198.4]) for the short term and having potentially fatal etiology (p = 0.027, OR: 11.7, 95% CI: [1.3–103]) for the long term were the only independent predictors of poor outcomes; whereas, the presence of periodic epileptiform discharges (PEDs) in EEG was the only independent predictor of refractoriness (p = 0.032, OR: 13.7, 95% CI: [1.3–148.5]). The patients with ≥ 3 Status Epilepticus Severity Score (STESS) did not have poorer outcomes in the short- (p = 0.157) and long term (p = 0.065). There was no difference between patients with 0–2, 3–4, and ≥ 4 mSTESS in the short- and long term in terms of outcome (p = 0.28 and 0.063, respectively). Also, there was no difference between subgroups (convulsive SE [CSE], nonconvulsive SE [NCSE], and epilepsia partialis continua [EPC]) in terms of STESS and mSTESS. When patients with EPC were excluded, both STESS and mSTESS scores of the patients correlated with poorer long-term outcomes (p = 0.025 and 0.017, respectively). The patients with ≥ 64 points in the Epidemiology-based Mortality in SE-Etiology, age, comorbidity, EEG (EMSE-EACE) score and those with ≥ 27 points in EMSE-Etiology, age, comorbidity (EMSE-EAC) score did not have poorer outcomes in the short term (p = 0.06 and 0.274, respectively) while they had significantly poorer outcome in the long term (p < 0.001 and 0.002, respectively). In subgroup analysis, patients with CSE with ≥ 64 points in EMSE-EACE had significantly poorer outcome in the both short- and long term (p = 0.014 and 0.012, respectively), and patients with CSE with ≥ 27 points in EMSE-EAC had significantly poorer outcome in the long term (p = 0.03) but not in the short term (p = 0.186). Outcomes did not correlate with EMSE scores in patients with NCSE and EPC. Status epilepticus was terminated with intravenous (IV) levetiracetam (LEV) in 68.75% of patients and with IV phenytoin (PHT) in 83.3% of patients. No statistically significant difference was found between the two groups in terms of efficacy (p = 0.334). Conclusion Being aged ≥ 65 years predicts poor short-term outcomes, and having potentially fatal etiology predicts poor long-term outcomes, which highlight the importance of SE treatment management in the elderly. Both STESS and mSTESS are not predictive for poor outcomes in EPC. Excluding patients with EPC, STESS, and mSTESS could predict poor long-term outcomes but not in the short term in SE. Epidemiology-based Mortality in Status Epilepticus score could predict poor outcome in the long term better than STESS and mSTESS. Specifically, EMSE scores correlated with poor outcome in patients with CSE but not with NCSE and EPC. New scales are needed to predict outcome especially in patients with NCSE and EPC. The presence of PEDs in EEG is a predictor of RSE, and EMSE score can also be used to predict RSE. There was no difference in the efficacy of IV LEV and IV PHT in SE. This study is significant for having one of the longest follow-up periods in the literature. [ABSTRACT FROM AUTHOR]

Purpose/aim: Memory impairment post-TBI is common, frequently persistent, and functionally debilitating. The purposes of this pilot study were to assess and to compare immediate behavioral auditory working memory and electrophysiologic effects of three different, randomized, conditions of left dorsolateral prefrontal cortex (LDLPFC) transcranial direct current stimulation (tDCS) applied to four neurotypical adults and four adults with chronic traumatic brain injury (TBI).Materials/methods: Pre- and post-anodal, cathodal, and sham tDCS auditory memory performance, auditory event-related potentials (P300 amplitude and latency) and power of alpha and theta EEG bands were measured across individuals in each group.Results: Post-anodal tDCS only, the neurotypical and TBI groups both demonstrated significantly improved immediate auditory memory function. Also post-anodal tDCS, the TBI group demonstrated significantly increased P300 amplitude versus post-sham tDCS. The neurotypical group demonstrated no pre- post-tDCS electrophysiologic changes across conditions.Conclusions: These findings are consistent with findings of other studies of immediate tDCS effects on other types of memory in neurotypical individuals and in individuals with Parkinson's disease, Alzheimer's disease and stroke and suggest that individuals with memory impairments second to chronic TBI may benefit from LDLPFC anodal tDCS. Pairing tDCS with traditional behavioral memory interventions may facilitate TBI rehabilitation outcomes and warrants continued investigation. [ABSTRACT FROM PUBLISHER]

In recent years, the clinical importance of laryngeal electromyography (LEMG) has been recognized. This method of investigation proved itself to be a valuable and indispensable tool regarding voice disorder management and requires multidisciplinary approach. In this article, we focus on the clinical usefulness of LEMG to assess inferior and superior motor neuron integrity by recording action potentials generated by muscle fibers of the larynx in the new field known as neurolaryngology. To facilitate the clinical application of this electrophysiologic test, we present a detailed description of LEMG techniques, which were applied for simultaneous bilateral recordings of the thyroarytenoid, cricothyroid and posterior cricoarytenoid muscles. Also, we analysed and measured the following electrophysiological parameters: 1) insertional activity; 2) spontaneous activity; 3) recruitment; 4) morphology of waveform. From a practical point of view, in our country, LEMG performance is still not a routine procedure in ENT and Phoniatric Departments. The difficulty of practical use of LEMG in Romania consists in technical limitations and it depends on the physician's experience regarding the examination technique and also the interpretation of electrophysiological results. Our current clinical experience shows that the use of LEMG contributes especially to the diagnosis, prognosis and treatment of patients with neurolaryngological disorders. [ABSTRACT FROM AUTHOR]

Background Cervical ribs have been reported to be present in about 0.5% of the general population, 10% of patients with cervical rib who are symptomatic usually have neurogenic symptoms, but some have arterial symptoms. In 1861, Coote was the first to excise a cervical rib through a supraclavicular approach and relieved the symptoms of thoracic outlet syndrome. Objective In this study, we address the efficacy and safety of a modification to the supraclavicular approach for resection of symptomatic cervical ribs. Patients and Methods The surgical team in collaboration with an anatomist performed cadaveric dissections of the posterior triangle of the neck in the Department of Anatomy, Ain Shams University. A prospective study was performed of 25 patients with moderate to severe neck or upper limb pain; this pain was resistant to medical treatment for at least 6 months. Preoperative cervical radiography showed cervical ribs. Pain was assessed by using the visual analog scale. Electrophysiologic tests were performed to confirm the diagnosis. In this study, we performed a modified supraclavicular interscalene approach with resection of the symptomatic rib and without resecting either of the scalene muscles or the first thoracic rib. Results A total of 25 patients were included in this study; the mean age was 36 years (± 12 standard deviation), and the mean follow-up period was 12.3 months. All patients had moderate (28%) to severe (72%) preoperative pain. Motor deficits were present in 6 cases (24%); Sensory manifestations were present in 80%. All patients had a relief of severe pain at the first postoperative visit in the first week. There were improvements in the motor power in 5 of the 6 patients who had preoperative motor deficit. Conclusions A modified supraclavicular interscalene approach for resection of symptomatic cervical ribs has been shown to be effective in the treatment of neuralgic pain. Compared with other approaches, it proved to be less invasive, with small transverse incision and without resection of scalenus anterior muscle. [ABSTRACT FROM AUTHOR]

Purpose: To assess the relationship between regional myocardial perfusion and sympathetic innervation parameters at myocardial scintigraphy and intra-cavitary electrophysiological data in patients with ventricular arrhythmias (VA) submitted to invasive electrophysiological study and ablation procedure. Methods: Sixteen subjects underwent invasive electrophysiological study with electroanatomical mapping (EAM) followed by trans-catheter ablations of VA. Before ablation all patients were studied with a combined evaluation of regional myocardial perfusion and sympathetic innervation by means of tomographic Tc-tetrofosmin and I- metaiodobenzylguanidine cadmium-zinc-telluride (CZT) scintigraphies, respectively. Off-line spatial co-registration of CZT perfusion and innervation data with the three-dimensional EAM reconstruction was performed in every patient. Results: CZT revealed the presence of myocardial scar in 55 (20 %) segments. Of the viable myocardial segments, 131 (60 %) presented a preserved adrenergic innervation, while 86 (40 %) showed a significantly depressed innervation (i.e. innervation/perfusion mismatch). On EAM, the invasively measured intra-cavitary voltage was significantly lower in scarred segments than in viable ones (1.7 ± 1.5 mV vs. 4.0 ± 2.2 mV, P < 0.001). Interestingly, among the viable segments, those showing an innervation/perfusion mismatch presented a significantly lower intra-cavitary voltage than those with preserved innervation (1.9 ± 2.5 mV vs. 4.7 ± 2.3 mV, P < 0.001). Intra-cardiac ablation was performed in 63 (23 %) segments. On multivariate analysis, after correction for scar burden, the segments showing an innervation/perfusion mismatch remained the most frequent ablation targets (OR 5.6, 95 % CI 1.5-20.8; P = 0.009). Conclusions: In patients with VA, intra-cavitary electrical abnormalities frequently originate at the level of viable myocardial segments with depressed sympathetic innervation that frequently represents the ultimate ablation target. [ABSTRACT FROM AUTHOR]

Hereditary neuropathy with liability to pressure palsies (HNPP) and Smith-Magenis syndrome (SMS) are genomic disorders associated with deletion copy number variants involving chromosome 17p12 and 17p11.2, respectively. Nonallelic homologous recombination (NAHR)-mediated recurrent deletions are responsible for the majority of HNPP and SMS cases; the rearrangement products encompass the key dosage-sensitive genes PMP22 and RAI1, respectively, and result in haploinsufficiency for these genes. Less frequently, nonrecurrent genomic rearrangements occur at this locus. Contiguous gene duplications encompassing both PMP22 and RAI1, i.e., PMP22- RAI1 duplications, have been investigated, and replication-based mechanisms rather than NAHR have been proposed for these rearrangements. In the current study, we report molecular and clinical characterizations of six subjects with the reciprocal phenomenon of deletions spanning both genes, i.e., PMP22- RAI1 deletions. Molecular studies utilizing high-resolution array comparative genomic hybridization and breakpoint junction sequencing identified mutational signatures that were suggestive of replication-based mechanisms. Systematic clinical studies revealed features consistent with SMS, including features of intellectual disability, speech and gross motor delays, behavioral problems and ocular abnormalities. Five out of six subjects presented clinical signs and/or objective electrophysiologic studies of peripheral neuropathy. Clinical profiling may improve the clinical management of this unique group of subjects, as the peripheral neuropathy can be more severe or of earlier onset as compared to SMS patients having the common recurrent deletion. Moreover, the current study, in combination with the previous report of PMP22- RAI1 duplications, contributes to the understanding of rare complex phenotypes involving multiple dosage-sensitive genes from a genetic mechanistic standpoint. [ABSTRACT FROM AUTHOR]

Background Although intraoperative nerve monitoring (IONM) is utilized increasingly, the information on the related anesthesia technique is limited. This study presents an up-to-date clinical algorithm, including setup and troubleshooting of an IONM system, endotracheal tube placement, and anesthetic parameters. To our knowledge, this is the first interdisciplinary collaborative protocol for monitored neck surgery based on the published evidence and clinical experience. Methods The Departments of Otolaryngology Head and Neck Surgery, Anesthesiology, and Audiology collaboratively developed a protocol for IONM of the recurrent laryngeal nerve (RLN) based on published evidence and our experience with 3000 patients over a 16-year period. Results No complications related to monitoring or endotracheal tube placement were noted when the IONM protocol was implemented at Massachusetts Eye and Ear Infirmary (MEEI). The IONM protocol has proven to be vital in standardizing care and in avoiding intraoperative errors. Conclusion An IONM system entails an anesthesiologist who understands the challenges posed by this technique; muscle relaxation must be minimized/eliminated to optimize IONM. © 2016 Wiley Periodicals, Inc. Head Neck 38: First-1494, 2016 [ABSTRACT FROM AUTHOR]

Objective: To review the literature systematically to determine whether noninvasive or invasive risk stratification, such as with an electrophysiological study of patients with asymptomatic pre-excitation, reduces the risk of arrhythmic events and improves patient outcomes.Methods: PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials (all January 1, 1970, through August 31, 2014) were searched for randomized controlled trials and cohort studies examining noninvasive or invasive risk stratification in patients with asymptomatic pre-excitation. Studies were rejected for low-quality design or the lack of an outcome, population, intervention, or comparator of interest or if they were written in a language other than English.Results: Of 778 citations found, 9 studies met all the eligibility criteria and were included in this paper. Of the 9 studies, 1 had a dual design-a randomized controlled trial of ablation versus no ablation in 76 patients and an uncontrolled prospective cohort of 148 additional patients-and 8 were uncontrolled prospective cohort studies (n=1,594). In studies reporting a mean age, the range was 32 to 50 years, and in studies reporting a median age, the range was 19 to 36 years. The majority of patients were male (range, 50% to 74%), and <10% had structural heart disease. In the randomized controlled trial component of the dual-design study, the 5-year Kaplan-Meier estimates of the incidence of arrhythmic events were 7% among patients who underwent ablation and 77% among patients who did not undergo ablation (relative risk reduction: 0.08; 95% confidence interval: 0.02 to 0.33; p<0.001). In the observational cohorts of asymptomatic patients who did not undergo catheter ablation (n=883, with follow-up ranging from 8 to 96 months), regular supraventricular tachycardia or benign atrial fibrillation (shortest RR interval >250 ms) developed in 0% to 16%, malignant atrial fibrillation (shortest RR interval ≤250 ms) in 0% to 9%, and ventricular fibrillation in 0% to 2%, most of whom were children in the last case.Conclusions: The existing evidence suggests risk stratification with an electrophysiological study of patients with asymptomatic pre-excitation may be beneficial, along with consideration of accessory-pathway ablation in those deemed to be at high risk of future arrhythmias. Given the limitations of the existing data, well-designed and well-conducted studies are needed. [ABSTRACT FROM AUTHOR]

Background: Cardiac electrophysiologic study and radiofrequency ablation (RFA) have become an established mode of treatment for patients with refractory arrhythmias. These procedures are carried out regularly at the cardiac catheterization laboratory of Madras Medical Mission India. Objective: The purpose of this study was to evaluate our experience with cardiac electrophysiologic studies (EPS) and RFA catheter of atrial fibrillation (AF). Materials and Methods: This was a retrospective study carried out in the Cardiac Electrophysiology Department of the Institute of Cardiovascular Diseases, Madras Medical Mission, India. All cases diagnosed to have AF following cardiac EPS between January 2010 and April 2014 was selected for the study. The records, which were obtained from the Cardiac Electrophysiology Clinical Research Office of Madras Medical Mission, were reviewed. Forty-nine cases were chosen for analysis, using SPSS statistical software version 15. Results: There were 49 patients, 23 males and 26 females. The mean age was 57.53 years. Commonly associated diseases were diabetes mellitus 8 (16.3%), hypertension 18 (36.7%), and coronary heart disease 14 (28.5%). The ventricular rate was rapid most cases (91.2%). AF was diagnosed as being paroxysmal in 40 (81.6%), persistent in 5 (10.2%), chronic in 3 (6.1%), and lone in 1 (2.0%). Ablation was carried out in 28 (57.1%), the success rate being 90% for pulmonary vein isolation, and 90.9% for atrioventricular node ablation. Complication rate was 2.04%. Conclusions: Treatment of AF by RFA is highly effective and safe. [ABSTRACT FROM AUTHOR]

Background: Stem cell therapy can be used for alleviating the neuropathic pain induced by spinal cord injuries (SCIs). However, survival and differentiation of stem cells following their transplantation vary depending on the host and intrinsic factors of the cell. Therefore, the present study aimed to determine the effect of stem cells derived from bone marrow (BM-MSC) and umbilical cord (UC-MSC) on neuropathic pain relief. Methods: A compression model was used to induce SCI in a rat model. A week after SCI, about 1 million cells were transplanted into the spinal cord. Behavioral tests, including motor function recovery, mechanical allodynia, cold allodynia, mechanical hyperalgesia, and thermal hyperalgesia, were carried out every week for 8 weeks after SCI induction. A single unit recording and histological evaluation were then performed. Results: We show that BM-MSC and UC-MSC transplantations led to improving functional recovery, allodynia, and hyperalgesia. No difference was seen between the two cell groups regarding motor recovery and alleviating the allodynia and hyperalgesia. These cells survived in the tissue at least 8 weeks and prevented cavity formation due to SCI. However, survival rate of UC-MSC was significantly higher than BM-MSC. Electrophysiological evaluations showed that transplantation of UC-MSC brings about better results than BM-MSCs in wind up of wide dynamic range neurons. Conclusions: The results of the present study show that BM-MSC and UC-MSC transplantations alleviated the symptoms of neuropathic pain and resulted in subsequent motor recovery after SCI. However, survival rate and electrophysiological findings of UC-MSC were significantly better than BM-MSC. [ABSTRACT FROM AUTHOR]

In humans, spontaneous movements are often preceded by early brain signals. One such signal is the readiness potential (RP) that gradually arises within the last second preceding a movement. An important question is whether people are able to cancel movements after the elicitation of such RPs, and if so until which point in time. Here, subjects played a game where they tried to press a button to earn points in a challenge with a brain-computer interface (BCI) that had been trained to detect their RPs in real time and to emit stop signals. Our data suggest that subjects can still veto a movement even after the onset of the RP. Cancellation of movements was possible if stop signals occurred earlier than 200 ms before movement onset, thus constituting a point of no return. [ABSTRACT FROM AUTHOR]

Surgical treatment of traumatic nerve lesions is a matter of debate, mostly about the timing and technical aspects of the procedure. In deciding about and planning the operation, it is often necessary to repeat the electrophysiological and neuroradiological studies several times. Here we present our experience with ultrasonography taken before and after surgery: this simple and handy tool allowed clear visualization of the preoperative anatomy, thorough preparation and fast carrying out of surgery, and accurate postoperative monitoring of the graft's vitality at follow-up. Though this is a limited series, the importance of ultrasonographic evaluation in traumatic peripheral nerve lesions appears remarkable. [ABSTRACT FROM AUTHOR]

In this study, we aimed to compare the results of transesophageal electrophysiologic studies (TEEPS) and intracardiac electrophysiologic studies (IEPS) in a cohort of pediatric patients with SVTs. The medical records of children aged between 0 and 18 years who underwent TEEPS between January 2007 and June 2012 were systematically reviewed, and those without pre-excitation and who underwent subsequent IEPS were identified. Post-procedural diagnoses were compared for compatibility. A total of 162 patients were included in the study with a mean age at diagnosis 11.6 ± 3.6 years. Tachycardia was induced in 152 patients by TEEPS and in 154 patients by IEPS. Overall, in 147 patients, tachycardia was induced by both TEEPS and IEPS. Diagnoses were compatible in 135 out of 147 patients (91.8 %). Nine out of the 12 patients with discrepant results were diagnosed with atrioventricular-reentrant tachycardia (AVRT) and three with atrioventricular nodal reentrant tachycardia (AVNRT) after TEEPS. Following IEPS, TEEPS diagnosis of AVRT was revised to typical AVNRT in 5 patients and atypical AVNRT in 4 patients. Two of the 3 patients who were diagnosed as having AVNRT following TEEPS were confirmed to have atrial tachycardia after IEPS, while the other patient was diagnosed with AVRT. Tachycardia terminated spontaneously in 3 patients, while overdrive pacing was attempted to terminate the tachycardia in 149 patients, with a success rate of 93.2 % (139/149). The diagnostic compatibility between TEEPS and IEPS is quite high. A diagnostic discrepancy mostly occurs in patients diagnosed with AVRT by TEEPS, and the possibility of atypical AVNRT should be considered in patients with a VA ≥70 ms to avoid such discrepancies. [ABSTRACT FROM AUTHOR]

Models are valuable tools to assess how deeply we understand complex systems: only if we are able to replicate the output of a system based on the function of its subcomponents can we assume that we have probably grasped its principles of operation. On the other hand, discrepancies between model results and measurements reveal gaps in our current knowledge, which can in turn be targeted by matched experiments. Models of the auditory periphery have improved greatly during the last decades, and account for many phenomena observed in experiments. While the cochlea is only partly accessible in experiments, models can extrapolate its behavior without gap from base to apex and with arbitrary input signals. With models we can for example evaluate speech coding with large speech databases, which is not possible experimentally, and models have been tuned to replicate features of the human hearing organ, for which practically no invasive electrophysiological measurements are available. Auditory models have become instrumental in evaluating models of neuronal sound processing in the auditory brainstem and even at higher levels, where they are used to provide realistic input, and finally, models can be used to illustrate how such a complicated system as the inner ear works by visualizing its responses. The big advantage there is that intermediate steps in various domains (mechanical, electrical, and chemical) are available, such that a consistent picture of the evolvement of its output can be drawn. However, it must be kept in mind that no model is able to replicate all physiological characteristics (yet) and therefore it is critical to choose the most appropriate model-or models-for every research question. To facilitate this task, this paper not only reviews three recent auditory models, it also introduces a framework that allows researchers to easily switch between models. It also provides uniform evaluation and visualization scripts, which allow for direct comparisons between models. [ABSTRACT FROM AUTHOR]

Objectives: Characterize treatment responsiveness in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) patients with diabetes mellitus (DM). Methods: We performed a retrospective chart review of CIDP subjects assessed between 1997 and 2013 and compared treatment response rates in those with and without DM, using different sets of criteria. Results: 99 CIDP patients were included, 34 CIDP+DM and 65 CIDP−DM patients, both having similar treatment response rates. CIDP patients fulfilling European Federation of Neurological Societies/Peripheral Nerve Society (EFNS/PNS) criteria had higher treatment response rates. Responders fulfilled a higher number of American Academy of Neurology (AAN) and EFNS/PNS criteria and had a higher number of demyelinating features in the total cohort and in CIDP−DM but not in CIDP+DM patients. CIDP+DM responders, however, had unique electrophysiologic characteristics. Conclusion: Fulfilling EFNS/PNS and AAN criteria, and higher number of demyelinating features, are associated with higher treatment response rates in CIDP−DM but not in CIDP+DM patients, implying the need for adjusting current criteria to predict treatment response rates in CIDP−DM patients. [ABSTRACT FROM AUTHOR]

The cause and treatment of functional movement disorders and nonepileptic spells in children is poorly understood, and an association with migraine has not previously been reported. We retrospectively reviewed children diagnosed with chronic or episodic migraine at our institution from 2006 to 2013 to determine the proportion with nonorganic movement disorders, their phenomenology, provoking factors, and natural history. Thirty-two patients were identified, representing 4.3% of patients with chronic migraine and 0.9% of patients with episodic migraine. Twenty-four of the 32 (75%) had chronic migraine, whereas 8 (25%) had episodic migraine. Nonepileptic spells was the most common phenomenon in both cohorts, followed by tremor and functional gait disorders. Severe migraine attacks preceded these movements in the majority of patients. With appropriate migraine therapy, significant reduction or resolution of these movements was reported. We conclude that nonorganic movement disorders are observed in pediatric migraine, are more prevalent among chronic migraineurs, and can resolve with improved pain control. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the accuracy of exercise testing for predicting accessory pathway characteristics in children with Wolff-Parkinson-White (WPW) syndrome. The study enrolled 37 children with WPW syndrome and candidates for invasive electrophysiologic study (EPS). Exercise testing was performed for all the study participants before the invasive study. Data from the invasive EPS were compared with findings from the exercise testing. The sudden disappearance of the delta (Δ) wave was seen in 10 cases (27 %). No significant correlation was found between the Δ wave disappearance and the antegrade effective refractory period of the accessory pathway (AERP-AP) or the shortest pre-excited RR interval (SPERRI). The sensitivity, specificity, and positive and negative predictive values of Δ wave disappearance, based on AERP-AP as gold standard, were respectively 29.4, 80, 71.4, and 40 %. The corresponding values with SPERRI as the gold standard were respectively 23.8, 71.4, 71.4 and 23.8 %. Exercise testing has a medium to low rate of accuracy in detecting low-risk WPW syndrome patients in the pediatric age group. [ABSTRACT FROM AUTHOR]

The role of IKCa in cardiac repolarization remains controversial and varies across species. The relevance of the current as a therapeutic target is therefore undefined. We examined the cellular electrophysiologic effects of IKCa blockade in controls, chronic heart failure (HF) and HF with sustained atrial fibrillation. We used perforated patch action potential recordings to maintain intrinsic calcium cycling. The IKCa blocker (apamin 100 nM) was used to examine the role of the current in atrial and ventricular myocytes. A canine tachypacing induced model of HF (1 and 4 months, n = 5 per group) was used, and compared to a group of 4 month HF with 6 weeks of superimposed atrial fibrillation (n = 7). A group of age-matched canine controls were used (n = 8). Human atrial and ventricular myocytes were isolated from explanted end-stage failing hearts which were obtained from transplant recipients, and studied in parallel. Atrial myocyte action potentials were unchanged by IKCa blockade in all of the groups studied. IKCa blockade did not affect ventricular myocyte repolarization in controls. HF caused prolongation of ventricular myocyte action potential repolarization. IKCa blockade caused further prolongation of ventricular repolarization in HF and also caused repolarization instability and early afterdepolarizations. SK2 and SK3 expression in the atria and SK3 in the ventricle were increased in canine heart failure. We conclude that during HF, IKCa blockade in ventricular myocytes results in cellular arrhythmias. Furthermore, our data suggest an important role for IKCa in the maintenance of ventricular repolarization stability during chronic heart failure. Our findings suggest that novel antiarrhythmic therapies should have safety and efficacy evaluated in both atria and ventricles. [ABSTRACT FROM AUTHOR]

Background. The assessment by electrophysiological study of sudden cardiac death risk of pure arrhythmological origin in the athletes with positive history of tachycardia was not previously described by the literature. Method and results. A prospective study conducted between 2010 and 2014 which included 62 patients, all athletes, performing category IIA sports or higher according to Bethesda Classification of sports, with positive history of arrhythmia (ECG documentation; syncope or aborted cardiac arrest; suggestive symptoms). All patients were evaluated by non invasive (ECG, effort testing) and invasive testing (electrophysiological study). The radiofrequency ablation was done in selected patients. The mean age of all patients was 17.62±6 years. There were found 29 patients (46.77%) with sudden cardiac death risk, from which 15 patients (24.19%) had only symptoms, not previous ECG documentation of arrhythmia and were discovered with high sudden death risk at electrophysiological study. The most common types of arrhythmia associated with sudden death risk were found to be the Wolff-Parkinson-White syndrome, atrioventricular nodal reentrant tachycardia and atrioventricular reciprocating orthodromic tachycardia due to concealed accessory pathways, ventricular tachycardia and premature ventricular contractions with degeneration into ventricular tachycardia. Conclusions. The sudden death risk is much more spread than thought among the athletes. This is due to cardiac remodeling at one hand and to associated discrete pathologic conditions on the other hand. Even if there is no documented tachycardia but the symptoms are suggestive for arrhythmic events, further investigation by effort testing and electrophysiological study in selected cases must be done. The two mechanisms of death that we assessed in association with the above described arrhythmias are degeneration into VF or hypo diastolic shock with hemodynamic collapse due to very fast tachycardia. In almost all cases, the radiofrequency ablation was the complete curative method, permitting the continuation of sports. [ABSTRACT FROM AUTHOR]

Abstract: Background: Morton's neuroma causes metatarsalgia due to the interdigital neuropathy. The small nerve diameter compromises their evaluation in image studies. To overcome this problem we propose a new electrophysiological test. Methods: We conducted a prospective case–control study performing a orthodromic electroneurography using subdermal electrodes in controls and patients to assess the validity. Additionally all patients were tested with magnetic resonance. Some patients required surgery and subsequent histological evaluation. Results: The new ENG procedure showed higher sensitivity and specificity. Methodological standardization was easy and the test was well tolerated by the subjects. Conclusions: Our test demonstrated remarkable diagnostic efficiency, and also was able to identify symptomatic patients undetected by magnetic resonance, which underlines the lack of correlation between the size and intensity of the lesion. This new electrophysiological method appears to be a highly sensitivity, well-tolerated, simple and low-cost for Morton's neuroma diagnosis. [Copyright &y& Elsevier]

Object-substitution masking (OSM) occurs when a target stimulus and a surrounding mask are displayed briefly together, and the display then continues with the mask alone. Target identification is accurate when the stimuli co-terminate but is progressively impaired as the duration of the trailing mask is increased. In reentrant accounts, OSM is said to arise from iterative exchanges between brain regions connected by two-way pathways. In an alternative account, OSM is explained on the basis of exclusively feed-forward processes, without recourse to reentry. Here I show that the feed-forward account runs afoul of the extant, behavioral, brainimaging, and electrophysiological evidence. Further, the feed-forward assumption that masking occurs when attention finds a degraded target is shown to be entirely ad hoc. In contrast, the evidence is uniformly consistent with a reentrant-processing account of OSM. [ABSTRACT FROM AUTHOR]

Our knowledge of the hearing abilities of frogs and toads is largely defined by work with a few well-studied species. One way to further advance comparative work on anuran hearing would be greater use of minimally invasive electrophysiological measures, such as the auditory brainstem response (ABR). This study used the ABR evoked by tones and clicks to investigate hearing in Cope's gray treefrog ( Hyla chrysoscelis). The objectives were to characterize the effects of sound frequency, sound pressure level, and subject sex and body size on ABRs. The ABR in gray treefrogs bore striking resemblance to ABRs measured in other animals. As stimulus level increased, ABR amplitude increased and latency decreased, and for responses to tones, these effects depended on stimulus frequency. Frequency-dependent differences in ABRs were correlated with expected differences in the tuning of two sensory end organs in the anuran inner ear (the amphibian and basilar papillae). The ABR audiogram indicated two frequency regions of increased sensitivity corresponding to the expected tuning of the two papillae. Overall, there was no effect of subject size and only small effects related to subject sex. Together, these results indicate the ABR is an effective method to study audition in anurans. [ABSTRACT FROM AUTHOR]

Background Ranolazine is evaluated for antiarrhythmic therapy of atrial fibrillation ( AF). The electrophysiologic mechanisms of ranolazine in combination with class III drugs were studied in an isolated whole-heart model of stretch-related AF. Methods and Results Thirty rabbits were fed with amiodarone (50 mg/kg/day, n = 10), dronedarone (50 mg/kg/day, n = 10), or placebo (n = 10) for 6 weeks. Subsequently, in isolated hearts, AF was induced by high-rate atrial pacing and acute atrial dilatation. In placebo-treated hearts, d,l-sotalol (50 μM) was acutely administered. Ranolazine (10 μM) was additionally infused in all groups. Chronic amiodarone (+26 ± 7 ms, P < 0.05) or dronedarone (+22 ± 4 ms, P < 0.05) as well as acute application of d,l-sotalol (+20 ± 3 ms, P < 0.05) increased atrial action potential duration (a APD90). Additional treatment with ranolazine did not significantly change a APD90 ( P = ns). Class III drugs did not affect interatrial conduction time, while ranolazine significantly increased it (amiodarone group: +15 ± 3 ms, dronedarone group: +11 ± 3 ms, sotalol group: +15 ± 6 ms; P < 0.05 each). Ranolazine led to an additional increase in atrial effective refractory period (a ERP), thus leading to an enhanced atrial postrepolarization refractoriness (a PRR, +17 ± 6 ms, +21 ± 4 ms and +16 ± 8 ms, P < 0.05, respectively). Acute atrial dilatation increased AF incidence compared with baseline. Amiodarone-pretreated hearts showed a lower incidence of AF. Additional infusion of ranolazine further diminished AF. Dronedarone or acute infusion of sotalol did not significantly suppress AF, while additional treatment with ranolazine in these groups also reduced AF incidence. Conclusion In this study, ranolazine on top of class III antiarrhythmic therapy had a beneficial effect. The increase in interatrial conduction time and marked atrial a PRR suppressed AF. These results shed further light on a potential therapeutic benefit of ranolazine on top of conventional antiarrhythmic therapy for rhythm control in AF. [ABSTRACT FROM AUTHOR]

An electrophysiologic study (EPS) of children and teenagers with paroxysmal supraventricular tachycardia (SVT) and normal electrocardiography (ECG) in sinus rhythm was evaluated. Generally, EPS is performed only before paroxysmal SVT ablation in these patients. In this study, 140 patients (mean age, 15 ± 3 years) with normal ECG in sinus rhythm were studied for SVT by a transesophageal route in baseline state and after isoproterenol. Idiopathic left or right ventricular tachycardia was diagnosed in four patients (3 %). Anterograde conduction over an atrioventricular (AV) left lateral ( n = 10) or septal ( n = 9) accessory pathway (AP) was noted in 19 patients (13.5 %) at atrial pacing. Orthodromic AV reentrant tachycardia (AVRT) was induced in these children. Five of the patients had a high rate conducted over AP (>240 bpm in baseline state or >290 bpm after isoproterenol). Two of the patients (a 10-year-old girl with well-tolerated SVT and a 17-year-old with syncope-related SVT) had the criteria for a malignant form with the induction of atrial fibrillation conducted over AP at a rate exceeding 290 bpm in baseline state. Of the 140 patients, 74 (53 %) had typical AV node reentrant tachycardia (AVNRT), nine had atypical AVNRT (6 %), 1 had atrial tachycardia (0.7 %), and 33 (23.5 %) had AVRT related to a concealed AP with only retrograde conduction. Electrophysiologic study is recommended for children with paroxysmal SVT and normal ECG in sinus rhythm. The data are helpful for guiding the treatment. Ventricular tachycardia or atrial tachycardia can be misdiagnosed. Masked preexcitation syndrome with anterograde conduction through AP was present in 13.5 % of the patients, and 1.4 % had a malignant preexcitation syndrome. [ABSTRACT FROM AUTHOR]

The article describes a single center findings validating a novel, noninvasive, whole heart, beat by beat, 3-dimensional mapping technology with invasive electrophysiological studies, including ablation, where applicable. Using an electrocardiographic mapping (ECM) system, the study involved 27 patients with various rhythm disorders. Findings showed that ECM successfully provided valid activation sequence maps that correlated well with invasive electrophysiological studies.

Transplantation studies in mice and rats have shown that human embryonic-stem-cell-derived cardiomyocytes (hESC-CMs) can improve the function of infarcted hearts, but two critical issues related to their electrophysiological behaviour in vivo remain unresolved. First, the risk of arrhythmias following hESC-CM transplantation in injured hearts has not been determined. Second, the electromechanical integration of hESC-CMs in injured hearts has not been demonstrated, so it is unclear whether these cells improve contractile function directly through addition of new force-generating units. Here we use a guinea-pig model to show that hESC-CM grafts in injured hearts protect against arrhythmias and can contract synchronously with host muscle. Injured hearts with hESC-CM grafts show improved mechanical function and a significantly reduced incidence of both spontaneous and induced ventricular tachycardia. To assess the activity of hESC-CM grafts in vivo, we transplanted hESC-CMs expressing the genetically encoded calcium sensor, GCaMP3 (refs 4, 5). By correlating the GCaMP3 fluorescent signal with the host ECG, we found that grafts in uninjured hearts have consistent 1:1 host-graft coupling. Grafts in injured hearts are more heterogeneous and typically include both coupled and uncoupled regions. Thus, human myocardial grafts meet physiological criteria for true heart regeneration, providing support for the continued development of hESC-based cardiac therapies for both mechanical and electrical repair. [ABSTRACT FROM AUTHOR]

Activation of hyperpolarization-activated cyclic nucleotidegated (HCN) channels is facilitated in vivo by direct binding of the second messenger cAMP. This process plays a fundamental role in the fine-tuning ofHCNchannel activity and is critical for the modulation of cardiac and neuronal rhythmicity. Here, we identify the pyrimidine cyclic nucleotide cCMP as another regulator of HCN channels. We demonstrate that cCMP shifts the activation curves of two members of the HCN channel family, HCN2 and HCN4, to more depolarized voltages. Moreover, cCMP speeds up activation and slows down deactivation kinetics of these channels. The two other members of theHCNchannel family, HCN1 and HCN3, are not sensitive to cCMP. The modulatory effect of cCMP is reversible and requires the presence of a functional cyclic nucleotide-binding domain. We determined an EC50 value of ∼30μM for cCMP compared with 1 μM for cAMP. Notably, cCMP is a partial agonist of HCN channels, displaying an efficacy of _0.6. cCMP increases the frequency of pacemaker potentials from isolated sinoatrial pacemaker cells in the presence of endogenous cAMP concentrations. Electrophysiological recordings indicated that this increase is caused by a depolarizing shift in the activation curve of the native HCN current, which in turn leads to an enhancement of the slope of the diastolic depolarization of sinoatrial node cells. In conclusion, our findings establish cCMP as a gating regulator of HCN channels and indicate that this cyclic nucleotide has to be considered in HCN channelregulated processes. [ABSTRACT FROM AUTHOR]

Patients with periventricular nodular heterotopia (PVNH) often have severe epilepsy. However, it is unclear how the heterotopia contributes to epileptogenesis. Recently, electrophysiologic studies using intraoperative depth electrodes have indicated that interaction between the heterotopia and overlying cortex is crucial for seizure onset. We performed an in vitro physiologic study using slices of resected brain from a 22-year-old man with PVNH, who manifested medically refractory mesial temporal lobe epilepsy. Preoperative evaluation indicated that the right mesial temporal structure and PVNH were the epileptogenic focus. The resected tissue was immediately immersed in cold artificial cerebrospinal fluid, and then slices of the brain tissue including the heterotopic nodules and overlying hippocampus were prepared. We electrically stimulated the incubated slices, and the elicited neural activities were analyzed as changes in the flavoprotein fluorescence signals. When we stimulated either the heterotopic nodule or the overlying hippocampus, clear functional coupling of neural activities between these structures was observed. The coupling response evoked by stimulation of the subiculum and developing within the heterotopic nodule was enhanced by application of bicuculline. Therefore, activities of the hippocampus and the nodule are closely correlated. [ABSTRACT FROM AUTHOR]

Associations between early deprivation and memory functioning were examined in 9- to 11-year-old children. Children who had experienced prolonged institutional care prior to adoption were compared to children who were adopted early from foster care and children reared in birth families. Measures included the Paired Associates Learning task from the Cambridge Neuropsychological Test and Automated Battery (CANTAB) and a continuous recognition memory task during which ERPs were also recorded. Children who experienced prolonged institutionalization showed deficits in both behavioral memory measures as well as an attenuated P300 parietal memory effect. Results implicate memory function as one of the domains that may be negatively influenced by early deprivation in the form of institutional care. [ABSTRACT FROM AUTHOR]

Psychiatric and neurologic disorders are associated with deficits in the postconflict recruitment of cognitive control. The primary aim of this study was to validate the relationship between cognitive functioning and indices of conflict adaptation. Event-related potentials were obtained from 89 healthy individuals who completed an Eriksen flanker task. Neuropsychological domains tested included memory, verbal fluency, and attention/executive functioning. Behavioral measures and N2 amplitudes showed significant conflict adaptation (i.e., previous-trial congruencies influenced current-trial measures). Higher scores on the attention/executive functioning and verbal fluency domains were associated with larger incongruent-trial N2 conflict adaptation; measures of cognitive functioning were not related to behavioral indices. This study provides initial validation of N2 conflict adaptation effects as cognitive function-related aspects of cognitive control. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to determine whether the timing of the most recent cardiac implantable electronic device (CIED) procedure, either a permanent pacemaker or implantable cardioverter-defibrillator, influences the clinical presentation and outcome of lead-associated endocarditis (LAE). Background: The CIED infection rate has increased at a time of increased device use. LAE is associated with significant morbidity and mortality. Methods: The clinical presentation and course of LAE were evaluated by the MEDIC (Multicenter Electrophysiologic Device Cohort) registry, an international registry enrolling patients with CIED infection. Consecutive LAE patients enrolled in the Multicenter Electrophysiologic Device Cohort registry between January 2009 and May 2011 were analyzed. The clinical features and outcomes of 2 groups were compared based on the time from the most recent CIED procedure (early, <6 months; late, >6 months). Results: The Multicenter Electrophysiologic Device Cohort registry entered 145 patients with LAE (early = 43, late = 102). Early LAE patients presented with signs and symptoms of local pocket infection, whereas a remote source of bacteremia was present in 38% of patients with late LAE but only 8% of early LAE (p < 0.01). Staphylococcal species were the most frequent pathogens in both early and late LAE. Treatment consisted of removal of all hardware and intravenous administration of antibiotics. In-hospital mortality was low (early = 7%, late = 6%). Conclusions: The clinical presentation of LAE is influenced by the time from the most recent CIED procedure. Although clinical manifestations of pocket infection are present in the majority of patients with early LAE, late LAE should be considered in any CIED patient who presents with fever, bloodstream infection, or signs of sepsis, even if the device pocket appears uninfected. Prompt recognition and management may improve outcomes. [ABSTRACT FROM AUTHOR]

Objective To perform a patient-pooled analysis of a routine invasive versus a selective invasive strategy in elderly patients with non-ST segment elevation acute coronary syndrome. Methods A meta-analysis was performed of patient-pooled data from the FRISC II-ICTUS-RITA-3 (FIR) studies. (Un)adjusted HRs were calculated by Cox regression, with adjustments for variables associated with age and outcomes. The main outcome was 5-year cardiovascular death or myocardial infarction (MI) following routine invasive versus selective invasive management. Results Regarding the 5-year composite of cardiovascular death or MI, the routine invasive strategy was associated with a lower hazard in patients aged 65-74 years (HR 0.72, 95% CI 0.58 to 0.90) and those aged ≥75 years (HR 0.71, 95% CI 0.55 to 0.91), but not in those aged <65 years (HR 1.11, 95% CI 0.90 to 1.38), p=0.001 for interaction between treatment strategy and age. The interaction was driven by an excess of early MIs in patients <65 years of age; there was no heterogeneity between age groups concerning cardiovascular death. The benefits were smaller for women than for men (p=0.009 for interaction). After adjustment for other clinical risk factors the HRs remained similar. Conclusion The current analysis of the FIR dataset shows that the long-term benefit of the routine invasive strategy over the selective invasive strategy is attenuated in younger patients aged <65 years and in women by the increased risk of early events which seem to have no consequences for long-term cardiovascular mortality. No other clinical risk factors were able to identify patients with differential responses to a routine invasive strategy. [ABSTRACT FROM AUTHOR]

Objective The aim of this study was to examine the accuracy in predicting pathway location in children with Wolff--Parkinson--White syndrome for each of seven published algorithms. Patients and interventions ECGs from 100 consecutive children with Wolff--Parkinson--White syndrome undergoing electrophysiological study were analysed by six investigators using seven published algorithms, six of which had been developed in adult patients. Main outcome measures Accuracy and concordance of predictions were adjusted for the number of pathway locations. Results Accessory pathways were left-sided in 49, septal in 20 and right-sided in 31 children. Overall accuracy of prediction was 30-49% for the exact location and 61-68% including adjacent locations. Concordance between investigators varied between 41% and 86%. No algorithm was better at predicting septal pathways (accuracy 5-35%, improving to 40-78% including adjacent locations), but one was significantly worse. Predictive accuracy was 24-53% for the exact location of right-sided pathways (50-71% including adjacent locations) and 32-55% for the exact location of left-sided pathways (58-73% including adjacent locations). Conclusions All algorithms were less accurate in our hands than in other authors' own assessment. None performed well in identifying midseptal or right anteroseptal accessory pathway locations. [ABSTRACT FROM AUTHOR]

Abstract: The primary somatosensory cortex (S1) projects to the thalamus and brainstem somatosensory nuclei and modulates somatosensory information ascending to the S1 itself. However, the projections from the S1 to the brainstem second-order somatosensory neuron pools have not been fully studied. To address this in rats, we first revealed the somatotopic representation of orofacial areas in the S1 by recording cortical surface potentials evoked by stimulation of the lingual, mental, infraorbital, and frontal nerves. We then examined the morphology of descending projections from the electrophysiologically defined orofacial S1 areas to the pons and medulla after injections of an anterograde tracer, biotinylated dextranamine (BDA), into the orofacial S1 areas. BDA-labeled axon terminals were seen mostly in the trigeminal sensory nuclear complex (TSNC) and had a strong contralateral predominance. They also showed a somatotopic arrangement in dorsoventral and superficial-deep directions within almost all rostrocaudal TSNC levels, and in a rostrocaudal direction within the trigeminal caudal subnucleus. In the principal nucleus (Vp) or oral subnucleus (Vo) of TSNC, the BDA-labeled axon terminals showed a somatotopic arrangement closely matched to that of the electrophysiologically defined projection sites of orofacial primary afferents; these projection sites were marked by injections of a retrograde tracer, Fluorogold (FG), into the Vp or Vo. The FG injections labeled a large number of S1 neurons, with a strong contralateral predominance, in a somatotopic manner, which corresponded to that presented in the electrophysiologically defined orofacial S1 areas. The present results suggest that the orofacial S1 projections to somatotopically matched regions of trigeminal second-order somatosensory neuron pools may allow the orofacial S1 to accurately modulate orofacial somatosensory transmission to higher brain centers including the orofacial S1 itself. [Copyright &y& Elsevier]

Coherence at the frequency of θ, α, and β EEG rhythms was analyzed in 14 adults and 23 children of 7-8 years old while they performed cognitive tasks requiring an involvement of working memory (WM). We used the pair matching paradigm in which subjects had to match a pair of stimuli shown in succession in the central visual field. The pairs of verbal and visuo-spatial stimuli were mixed together and presented in a pseudo random order. Each pair was preceded by a warning signal that did not specify a modality of upcoming stimuli. We analyzed EEG segments recorded (i) in the rest condition, (ii) prior to the first (reference) stimulus (maintenance of nonspecific voluntary attention), and (iii) prior to the second (test) stimulus (retention of information in WM). In the present study we focused on the regulatory functional components of WM, and therefore, the stimulus modality has not been taken into account. In adults, maintaining nonspecific voluntary attention was accompanied by an increase of the strength of θ-related functional coupling between medial areas of the frontal cortex and temporal cortical zones and by a strengthening of local β-related functional connectivity in the fronto-central areas of the cortex. In children, no such increase was found for θ rhythm; for β rhythm the increase was limited to several short-range functional links. In adults, the retention of information in WM was accompanied by the growth in α coherence in distant fronto-parietal links, predominantly in the right hemisphere, while in children information retention was accompanied by the growth of θ coherence in the inferio-temporal and parietal cortical regions. The results of the study point to a relative immaturity of the mechanisms of executive control of WM in children of 7-8 years old. [ABSTRACT FROM AUTHOR]

Background: Motor impairments are common in autism spectrum disorders (ASD). Electrophysiologic studies reveal abnormalities in the preparation of movement; repetitive transcranial magnetic stimulation (rTMS) to key motor cortical sites may therefore be a useful technique for improving motor function in ASD. Objective: To examine whether rTMS can improve electrophysiologic and behavioral indices of motor activity. Methods: Eleven participants with ASD completed three sessions in which they were administered one of three rTMS conditions (left M1, supplementary motor area [SMA], sham) at 1 Hz for 15 minutes. Movement-related cortical potentials (MRCPs) were assessed before and after rTMS. Results: rTMS to the SMA was associated with a gradient increase to the early component of MRCPs, whereas rTMS to left M1 produced a stronger gradient in the late component. Conclusions: rTMS appears to improve movement-related electrophysiologic activity in ASD, perhaps through an influence on cortical inhibitory processes. [Copyright &y& Elsevier]

Critical care has focused on recovery from acute organ failure and resuscitation. Neuromuscular abnormalities related to critical illness is not uncommon in critically ill patients, but ihey were relatively underestimated and unnoticed. Intensive care unit acquired weakness (ICUAW) leading to severe functional impairments in ICU survivors can be divided into two disease entities: critical illness polyneuropathy (CIP) and critical illness myopathy (CIM). Electrophysiologic study, muscle biopsy anc physical examination are helpful to diagnose ICUAW. Several researches and reviews identified many risk factors including systemic inflammation, corticosteroids, hyperglycemia, and immobility. Additional research is needed to identify the pathogenesis of this disorder and to testify its preventive or therapeutic modalities. [ABSTRACT FROM AUTHOR]

J. Neurochem. (2011) 119, 676-685. Abstract Tyrosine 37 in the first transmembrane (TM1) domain is highly conserved in ATP-gated P2X receptors suggesting its fundamental role. We tested whether Y37 contributes to the desensitization of P2X3 receptors, which is currently not well understood. By combining electrophysiological, imaging and modeling approaches, we studied desensitization of various Y37 P2X3 mutants and potential partners of Y37. Unlike the membrane current of the WT receptor, which desensitized in seconds, Y37A mutant current did not fully desensitize even after minutes-long applications of β,γ-meATP, α,β-meATP, ATP or 2MeS-ATP. The fractional calcium current was enhanced in the Y37A mutant. Y37F did not rescue the native P2X3 phenotype indicating a role for the hydroxyl group of Y37 for the WT receptor. Homology modeling indicated I318 or I319 in TM2 as potential partners for Y37 in the receptor closed state. We tested this hypothesis by creating a permanent interaction between the two residues via disulfide bond. Whereas single Y37C, I318C and I319C mutants were functional, the double mutants Y37C-I318C and Y37C-I319C were non-functional. Using a cyclic model of receptor operation, we suggest that the conserved tyrosine 37 links TM1 to TM2 of adjacent subunit to stabilize desensitized states and restricts calcium permeability through the ion channel. [ABSTRACT FROM AUTHOR]