Heart rate variability analysis indicates preictal parasympathetic overdrive preceding seizure‐induced cardiac dysrhythmias leading to sudden unexpected death in a patient with epilepsy

Evidence for seizure‐induced cardiac dysrhythmia leading to sudden unexpected death in epilepsy (SUDEP) has been elusive. We present a patient with focal cortical dysplasia who has had epilepsy for 19 years and was undergoing presurgical evaluation. The patient did not have any cardiologic antecedents. During long‐term video–electroencephalography (EEG) monitoring, following a cluster of secondarily generalized tonic–clonic seizures (GTCS), the patient had prolonged postictal generalized EEG suppression, asystole, followed by arrhythmia, and the patient died despite cardiopulmonary resuscitation. Analysis of heart rate variability showed a marked increase in the parasympathetic activity during the period preceding the fatal seizures, compared with values measured 1 day and 7 months before, and also higher than the preictal values in a group of 10 patients with GTCS without SUDEP. The duration of the QTc interval was short (335–358 msec). This unfortunate case documented during video‐EEG monitoring indicates that autonomic imbalance and seizure‐induced cardiac dysrhythmias contribute to the pathomechanisms leading to SUDEP in patients at risk (short QT interval). A PowerPoint slide summarizing this article is available for download in the Supporting Information section here .     

Effects of Neurofeedback Training on Inhibitory Capacities in ADHD Children: A Single-Blind,Randomized, Placebo-Controlled Study

Introduction. Studies performed during the last decades suggest that neurofeedback (NF) training can effectively reduce symptomatology in children with Attention deficit hyperactivity disorder (ADHD). Yet questions remain concerning specific effects of NF training in ADHD children, because these studies did not use a randomized, placebo-controlled approach. To address this issue, such an approach was used in the present study to measure the impact of NF training on inhibitory capacities.

Method. Nine ADHD children (with no comorbidity), aged 8 to 13 years, were randomly assigned to either an experimental group (n = 5) or a placebo group (n = 4). For both groups, training protocols comprised 40 one-hr sessions (20 meetings of 2 sessions each). Sensorimotor rhythm/Theta training was used in the experimental group. Prerecorded sessions of the first author's EEG activity were used in the placebo group. Pre- and posttraining assessments consisted of the Conner's Parent Rating Scales (CPRS–R) and neuropsychological tests. A multiple case study strategy was applied for data analysis using a Reliable Change Index when applicable.

Results. One experimental participant was a dropout, and one placebo participant had to be discontinued due to adverse effects. The latter participant accepted to undergo posttraining evaluations; hence an Intention-to-Treat analysis was performed on this participant's data. Remaining participants showed significant improvements on the CPRS–R. Improvements were measured on the Variability measure of the CPT–II consistently across the placebo group and on the Inhibition Condition of the Stroop Task for all but one placebo participant. The same trend was found for the Inhibition/Switching Condition (Stroop Task) across the experimental group (n = 4).

Conclusion. The small sample size precludes from evaluating specific neurofeedback effects. Still, the presence of placebo responses suggests that other factors, such as motivation or expectations, might contribute to the outcome of NF training in children with ADHD.     

The Production of High Affinity Monoclonal Antibodies to Human Chorionic Gonadotropin and Their Application to Immunoradiometric Assay

Abstract

Production of monoclonal antibodies against hCG has been studied using hCG as the antigen. This study reports the successful isolation of hybrid clones secreting monoclonal antibodies specific for hCG with an affinity constant higher than 10¹⁰M^?l. Of 23 fusions, only 17 fusions have produced positive clones which secrete antibodies giving high levels of binding with ^l25I-labelled hCG in the supernatant. Finally, 6 different monoclonal antibodies have been isolated; 4 of them, specific for the β-subunit, with a Ka approximately 1.1–4.0 ± 10¹¹M^?1 and 2 others, specific for the α-subunit, presenting an affinity of 2.5 ± 10¹⁰M^?l. When the antibodies specific for the β-subunit are used, specific and highly sensitive radioim-munoassays are obtained after only 3 hrs of incubation. Using iodinated monoclonal antibodies specific for the α-subunit and tubes coated with antibodies against the β-subunit, we have developped sensitive immunoradiometric assays.     

Fibrillin-1 genotype and risk of prevalent hypertension: A study in two independent populations

Abstract Objective. Mutations in the fibrillin-1 gene are the cause of Marfan syndrome. We wanted to investigate the relationship between a mutation in this gene and risk of prevalent hypertension. Methods. In a cross-sectional study, the effect of a G-A substitution in intron 27 in the fibrillin-1 gene (rs11856553) on risk of prevalent hypertension was studied in two large population-based studies: the Health 2006 study, consisting of 3193 women and men, age 18-69 years, and the MONICA10 study, consisting of 2408 women and men, age 41-72 years. In 1646 MONICA10 participants, blood pressure (BP) was also measured by 24-h ambulatory recordings. Results. Among the 3193 Health 2006 participants 23 had the G-A variant, and among the 2408 MONICA10 participants 18 had the G-A variant. In Health 2006, the odds ratio estimate (95% confidence intervals) for the G-A variant for risk of hypertension, defined as systolic (S) BP ≥?140 mmHg or diastolic (D) BP ≥?90 mmHg or on antihypertensive medicine, was 2.67 (1.14-6.18), p =?0.022. The corresponding figure for moderate to severe hypertension, defined as SBP ≥?160 mmHg or DBP ≥?100 mmHg, was 9.68 (4.24-22.12), p 相似文献   

Genetic variation in the natriuretic Peptide system, circulating natriuretic Peptide levels, and blood pressure: an ambulatory blood pressure study

BackgroundIn a large collaborative study (n > 50,000), common variants in the natriuretic peptide (NP) genes were found to be associated with circulating NP levels and also with blood pressure (BP) levels based on office BP measurements (OBPMs). It is unknown if determining an individual's BP by 24-h ambulatory BP measurements (ABPMs) will influence the effect of NP gene variations on BP levels.MethodsWe used rs632793 at the NPPB (NP precursor B) locus to investigate the relationship between genetically determined serum N-terminal pro-brain NP (NT-proBNP) concentrations and BP levels determined by both 24-h ABPMs and OBPMs in a population consisting of 1,397 generally healthy individuals taking no BP-lowering drugs.Resultsrs632793 was significantly correlated with serum Nt-proBNP levels (r = 0.10, P = 0.0003), and participants with the A:A genotype had lower serum Nt-proBNP levels than participants with the G:G genotype (geometric mean (95% confidence interval (CI)): 34.8 (31.5-38.4) pg/ml vs. 48.1 (41.9-55.3) pg/ml, P = 0.0002), but higher 24-h ambulatory BP levels (mean difference (95% CI): 2.0 (0.1-4.1) mm Hg, P = 0.043, for systolic BP and 1.7 (0.4-3.1) mm Hg, P = 0.011, for diastolic BP). Office BP decreased across the genotypes from A:A to G:G, but the differences did not reach statistical significance (P ≥ 0.12).ConclusionsThis study suggests that 24-h ABPMs is a better method than OBPMs to detect significant differences in BP levels related to genetic variance and provides further evidence that the NP system plays an important role in BP regulation.American Journal of Hypertension 2012; doi:10.1038/ajh.2012.96.