Short term priming effect of brain-actuated muscle stimulation using bimanual movements in stroke.

OBJECTIVE: Brain-computer interface triggered-functional electrical stimulation (BCI-FES) is an emerging neurorehabilitation therapy post stroke, mostly for the affected hand. We explored the feasibility of a bimanual BCI-FES and its short-term priming effects, i.e. stimuli-induced behaviour change. We compared EEG parameters between unimanual and bimanual movements and differentiated the effect of age from the effect of stroke. METHODS: Ten participants with subacute stroke, ten age-matched older healthy adults, and ten younger healthy adults underwent unimanual and bimanual BCI-FES sessions. Delta alpha ratio (DAR) and brain symmetry index (BSI) were derived from the pre- and post- resting-state EEG. Event-related desynchronization (ERD) and laterality index were derived from movement- EEG. RESULTS: Participants were able to control bimanual BCI-FES. ERD was predominantly contralateral for unimanual movements and bilateral for bimanual movements. DAR and BSI only changed in healthy controls. Baseline values indicated that DAR was affected by stroke while BSI was affected by both age and stroke. CONCLUSIONS: Bimanual BCI control offers a larger repertoire of movements, while causing the same short-term changes as unimanual BCI-FES. Prolonged practice may be required to achieve a measurable effect on DAR and BSI for stroke. SIGNIFICANCE: Bimanual BCI-FES is feasible in people affected by stroke.

The Fourier analysis applied to the relationship between (7)Be activity in the Serbian atmosphere and meteorological parameters.

Air sample monitoring in Serbia, Belgrade started in the 1960s, while (7)Be activity in air and total (dry and wet) deposition has been monitored for the last 22 years by the Environment and Radiation Protection Department of the Institute for Nuclear Sciences, Vinca. Using this data collection, the changes of the (7)Be activity in the air and the total (wet and dry) deposition samples, as well as their correlation with meteorological parameters (temperature, pressure, cloudiness, sunshine duration, precipitation and humidity) that affect (7)Be concentration in the atmosphere, were mathematically described using the Fourier analysis. Fourier analysis confirmed the expected; the frequency with the largest intensity in the harmonic spectra of the (7)Be activity corresponds to a period of 1 year, the same as the largest intensity frequency in Fourier series of meteorological parameters. To analyze the quality of the results produced by the Fourier analysis, we compared the measured values of the parameters with the values calculated according to the Fourier series. Absolute deviations between measured and predicted mean monthly values are in range from 0.02 mBq/m(3) to 0.7 mBq/m(3) for (7)Be activity in air, and 0.01 Bq/m(2) and 0.6 Bq/m(2) for (7)Be activity in deposition samples. Relatively good agreement of measured and predicted results offers the possibility of prediction of the (7)Be activity.

The chaotic sequences in the Bray-Liebhafsky reaction in an open reactor.

Attractor reconstruction is done from the time series obtained by experimental investigation and by deterministic and stochastic simulation of the Bray-Liebhafsky oscillatory reaction. The appearance of deterministic chaos is confirmed and proven by both simulation and experiment, determining Lyapunov exponents for the sequences of flow rate values, as the control parameter. Moreover, unusual chaotic series were additionally recorded in the experiments, which cannot be found in deterministic numerical simulations. Therefore, an explanation of the difference between the dynamic behavior in the experiment and the deterministic simulation was sought and stochastic simulations based on the same reaction model were particularly useful. The fine structure of the chaotic windows, derived from the analysis of deterministic simulations in the range of flow rate values, made the system highly susceptible to noise induced effects, in general.

Pregnancy-associated CA125 antigen as mucin: evaluation of ferning morphology.

CA125 antigen is a high molecular mass, structurally heterogeneous, mucin-type molecule expressed during embryonic development as well as in adult human tissues. This study was aimed at investigating its mucin-related property of ferning, as a general complementary way of characterization. Pregnancy-associated CA125 antigen (pCA125) was examined using light, transmission and scanning electron microscopy and compared with cancer-derived CA125 antigen (cCA125). The results obtained for spread-out, air-dried pCA125 and cCA125 samples revealed clear differences in the patterns of crystalline as well as amorphous material. Thus, the fern-like crystals were mainly sparsely distributed and their morphology was atypical. The extent of crystallization of pCA125 was moderately lower than that of cCA125 antigen, whereas variation in the size and spatial organization of fern crystals was evident. Besides the material with a crystalline appearance, differences in the organic substrate were also noticeable. In contrast to the sponge-like appearance of pCA125, cCA125 had a more compact structure. These initial data may be relevant for relating biochemical properties of CA125 antigen with its morphology as a basis for elucidating its still obscure function under different physiological conditions.

Sialylation and fucosylation of cancer-associated prostate specific antigen.

PURPOSE: To examine sialylation and fucosylation of prostate cancer-associated prostate-specific antigen (PCa PSA) from localized prostate cancer and from metastatic prostate cancer, as relevant indicators of tumour stage-dependent microheterogeneity of its oligosaccharide chain. MATERIALS AND METHODS: Sera and urine were collected from a group of consenting patients and used as source of the examined PSA. Lectin-affinity chromatography was performed on the columns with immobilized sialic acid-specific lectins Sambucus nigra agglutinin (SNA) and Maackia amurensis lectin (MAA), and fucose-specific lectins Aleuria aurantia agglutinin (AAA) and Ulex europaeus agglutinin (UEA). PSA elution from the corresponding columns was monitored by measuring immunoreactivity to free (f) PSA form. RESULTS: The results of lectin affinity chromatographies of PCa PSA indicated distinct and high microheterogeneity of its oligosaccharide chain in respect to the presence of glycoforms differing in the position and the type of linkage of sialic acid or fucose, as well as alterations related to the examined PSA source (localized or metastatic prostate cancer). CONCLUSION: The observed decrease in SNA reactivity to metastatic PCa PSA in comparison with PCa PSA from localized prostate cancer may be of interest in the monitoring of response to therapy and scoring of its metastatic potential.