Tensor decomposition of human narrowband oscillatory brain activity in frequency, space and time.

Many brain processes in health and disease are associated with modulation of narrowband brain oscillations (NBOs) in the scalp-recorded EEG, which exhibit specific frequency spectra and scalp topography. Isolating and tracking NBOs over time using algorithms is useful in domains such as brain-computer interfaces or when measuring the EEG effects of experimental manipulations. Previously, we successfully applied modified tensor methods for identifying and tracking NBO activity over time or conditions.

Profiling continuous sleep representations for better understanding of the dynamic character of normal sleep.

The amount and quality of sleep substantially influences health, daily behaviour and overall quality of life. The main goal of this study was to investigate to what extent sleep structure, as derived from the polysomnographic (PSG) recordings of nocturnal human sleep, can provide information about sleep quality in terms of correlating with a set of variables representing the daytime subjective, neurophysiological and cognitive states of a healthy population without serious sleep problems. We focused on a continuous sleep representation derived from the probabilistic sleep model (PSM), which describes the microstructure of sleep by a set of sleep probabilistic curves representing a finite number of sleep microstates.

Effects of mirror-box therapy on modulation of sensorimotor EEG oscillatory rhythms: a single-case longitudinal study.

We provide direct electrophysiological evidence that mirror therapy (MT) can change brain activity and aid in the recovery of motor function after stroke. In this longitudinal single-case study, the subject was a 58-yr-old man with right-hand hemiplegia due to ischemic stroke. Over a 9-mo period we treated him with MT twice a week and measured electroencephalograms (EEG) before, during, and after each therapy session.

Feature clustering of intracranial pressure time series for alarm function estimation in traumatic brain injury.

Objective: The conventional application of intracranial pressure (ICP) monitoring of traumatic brain injury (TBI) patients consists merely in the acquisition of ICP values in discrete time and their comparison to the established ICP threshold. An exceeding of this threshold triggers a special emergency treatment protocol. This paper addresses the possibility of making use of the rich information latent in the ICP records of known vital and fatal outcomes gathered during real clinical practice of treating TBI patients.

On the Individuality of Sleep EEG Spectra.

Research in recent years has supported the hypothesis that many properties of the electroencephalogram (EEG) are specific to an individual. In this study, the intra- and inter-individual variations of sleep EEG signals were investigated. This was carried out by analyzing the stability of the average EEG spectra individually computed for the Rechtschaffen and Kales (RK) sleep stages.

In search of objective components for sleep quality indexing in normal sleep.

The main goal of this study was to investigate to what extent polysomnographic (PSG) recordings of nocturnal human sleep can provide information about sleep quality in terms of correlation with a set of daytime measures. These measures were designed with the aim of comprising selected quality of night sleep and consist of subjective sleep quality ratings, neuropsychological tests and physiological parameters. First, a factor analysis model was applied to the large number of daytime measures of sleep quality in order to detect their latent structure.

Extracting more information from EEG recordings for a better description of sleep.

We are introducing and validating an EEG data-based model of the sleep process with an arbitrary number of different sleep stages and a high time resolution allowing modeling of sleep microstructure. In contrast to the standard practice of sleep staging, defined by scoring rules, we describe sleep via posterior probabilities of a finite number of states, not necessarily reflecting the traditional sleep stages. To test the proposed probabilistic sleep model (PSM) for validity, we correlate statistics derived from the state posteriors with the results of psychometric tests, physiological variables and questionnaires collected before and after sleep.

Mutation analysis of the MECP2 gene in patients of Slavic origin with Rett syndrome: novel mutations and polymorphisms.

Rett syndrome (RTT), an X-linked dominant neurodevelopmental disorder in females, is caused mainly by de novo mutations in the methyl-CpG-binding protein 2 gene (MECP2). Here we report mutation analysis of the MECP2 gene in 87 patients with RTT from the Czech and Slovak Republics, and Ukraine. The patients, all girls, with classical RTT were investigated for mutations using bi-directional DNA sequencing and conformation sensitive gel electrophoresis analysis of the coding sequence and exon/intron boundaries of the MECP2 gene.

Brain-computer interfaces for 1-D and 2-D cursor control: designs using volitional control of the EEG spectrum or steady-state visual evoked potentials.

We have developed and tested two electroencephalogram (EEG)-based brain-computer interfaces (BCI) for users to control a cursor on a computer display. Our system uses an adaptive algorithm, based on kernel partial least squares classification (KPLS), to associate patterns in multichannel EEG frequency spectra with cursor controls. Our first BCI, Target Practice, is a system for one-dimensional device control, in which participants use biofeedback to learn voluntary control of their EEG spectra.

Analbuminemia in a Slovak Romany (gypsy) family: case report and mutational analysis.

Background: Analbuminemia is a rare autosomal recessive disorder manifested by the absence, or severe reduction, of circulating serum albumin. Here we report three new cases of hereditary analbuminemia, fortuitously detected in three Slovak Romany children, members of the same family, and define the molecular defect that causes the analbuminemic trait.

Methods: Total DNA, extracted from peripheral blood samples from six members of the family, was PCR-amplified using oligonucleotide primers designed to amplify the 14 exons of the human albumin gene and the flanking intron regions.

[Congenital disorder of type Ia protein glycosylation: clinical, biochemical and molecular characteristics in 2 siblings with cerebellar hypoplasia].

Background: Congenital disorders of glycosylation (CDG syndrome) represent a newly delineated group of inherited diseases of glycoprotein synthesis. We present results of biochemical and molecular analyses in two Czech patients with CDG Ia syndrome.

Methods And Results: Serum concentrations of the nonglycosylated and hypoglycosylated transferrin were measured using turbidimetric immunoassay.

Multimodal neuroelectric interface development.

We are developing electromyographic and electroencephalographic methods, which draw control signals for human-computer interfaces from the human nervous system. We have made progress in four areas: 1) real-time pattern recognition algorithms for decoding sequences of forearm muscle activity associated with control gestures; 2) signal-processing strategies for computer interfaces using electroencephalogram (EEG) signals; 3) a flexible computation framework for neuroelectric interface research; and d) noncontact sensors, which measure electromyogram or EEG signals without resistive contact to the body.

[Analysis of the most frequent mutations in girls with Rett syndrome].

Background: Rett syndrome is an X-linked dominant neurodevelopmental disorder affecting 1 from 10,000 to 15,000 females worldwide. The responsible gene, encoding methyl-CpG binding protein 2 was recently identified. Methyl-CpG binding protein 2 is thought to act as a global transcriptional repressor.

Evaluation of mutation screening by heteroduplex analysis in acute intermittent porphyria: comparison with denaturing gradient gel electrophoresis.

Acute intermittent porphyria is the major autosomal dominant form of acute hepatic porphyrias. The disease is due to mutations in the gene encoding for porphobilinogen deaminase (PBGD). Many different strategies have been developed to screen for mutations.

Systematic analysis of coproporphyrinogen oxidase gene defects in hereditary coproporphyria and mutation update.

Hereditary coproporphyria (HC) is an acute hepatic porphyria with autosomal dominant inheritance caused by deficient activity of coproporphyrinogen III oxidase (CPO). Clinical manifestations of the disease are characterized by acute attacks of neurological dysfunction often precipitated by drugs, fasting, cyclical hormonal changes, or infectious diseases. Skin photosensitivity may also be present.

Neonatal hemolytic anemia due to inherited harderoporphyria: clinical characteristics and molecular basis.

Porphyrias, a group of inborn errors of heme synthesis, are classified as hepatic or erythropoietic according to clinical data and the main site of expression of the specific enzymatic defect. Hereditary coproporphyria (HC) is an acute hepatic porphyria with autosomal dominant inheritance caused by deficient activity of coproporphyrinogen III oxidase (COX). Typical clinical manifestations of the disease are acute attacks of neurological dysfunction; skin photosensitivity may also be present.

Molecular analysis of porphobilinogen (PBG) deaminase gene mutations in acute intermittent porphyria: first study in patients of Slavic origin.

Acute intermittent porphyria (AIP) is an autosomally dominant inherited metabolic disorders caused by decreased activity of porphobilinogen deaminase, the third enzyme in the human heme biosynthetic pathway. We report here the first mutations in the human porphobilinogen deaminase gene in seven unrelated patients from the Czech and Slovak Republics with acute intermittent porphyria. We used denaturing gradient gel electrophoresis to screen all 15 exons and exon/intron boundaries of the porphobilinogen deaminase gene.

Protoporphyrinogen oxidase: complete genomic sequence and polymorphisms in the human gene.

Variegate porphyria (VP) is an autosomal dominant disorder of heme synthesis caused by a partial deficiency of protoporphyrinogen oxidase (PPOX). Human cDNA encoding PPOX has been recently sequenced and the gene has been cloned, assigned to chromosome 1q23, and its exon/intron organization has been characterized. We report here the complete nucleotide sequence of the Human PPOX gene.