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Biomedical subjects

M Beranová

Publications and source records attributed to M Beranová.

9 recordsLinked to original sources
PubMed2003

Congenitally determined neurodegeneration "Lurcher" induces morphofunctional changes of thymus.

A significantly higher frequency of apoptosis was documented by flow cytometry and by ELISA analysis, and significantly higher numbers of necrotic cells were demonstrated by ELISA within the thymus of Lurcher mice in comparison with the control C3H mice. These can be regarded as important markers of degenerative changes in this primary immune organ. This tendency is supported by histological observation of the absence of a clear interface between thymic cortex and medulla and an insignificantly increased number of Hassall's corpuscles resembling an onset of thymic atrophy.

Animals↗
PubMed1993

Advanced EMG techniques in diagnostics of spinal muscular atrophies and motor neuron disease--magnetic stimulation, single fiber EMG and macro EMG.

Motor neuron disease (MND) and spinal muscular atrophies (SMA) are difficult to diagnose with classical EMG methods because significant findings appear relatively late and both groups of diseases show neurogenic type of record differing only in a relatively greater amount of fasciculations and higher amplitude of motor unit potential (MUP) in MND compared with SMA. We examined 12 patients with MND-amyotrophic lateral sclerosis and 7 patients with SMA type III and IV according to Swash with advanced EMG techniques-magnetic stimulation, single fiber and macro EMG. With transcranial magnetic stimulation, a significant prolongation of cortical latency was found in MND (P < 0.0001 right hand and P < 0.0005 left hand) against SMA, where it was almost normal. With single fiber EMG, mean jitter was less markedly increased in MND (P < 0.05 against SMA) and fiber density was lower in MND (P < 0.005). With macro EMG, no significant difference was found in either macro amplitude or area. Macro fiber density was also lower in MND (P < 0.005). Advanced EMG techniques proved to differentiate clearly the III. (Kugelberg-Welander) and IV. (adult) type of SMA from MND-amyotrophic lateral sclerosis.

Adult↗
PubMed1992

Single fiber EMG in multiple sclerosis.

A group of 25 patients with sclerosis multiplex (SM) was examined by means of single fiber (SF) EMG. This group had the mean value of jitter 55.0 +/- 4.5 microseconds and fiber density (FD) 2.15 +/- 0.12. The findings of the patients with the first attack of illness and the findings of the patients with twenty-year duration are the same. A hypothesis is suggested that not only the peripheral neuron but also the CNS structures take part in the increase of jitter. The different results of stimulated single fiber (SSF) and SF EMG are discussed; the former reflects only the peripheral part of the nervous system due to peripheral stimulation. The higher levels of CNS cannot take part in it.

Adolescent↗
PubMed1992

Single fiber EMG in cerebrovascular stroke (CVS).

This paper gives previously unpublished data about fiber density (FD) and jitter in patients with CVS. The cluster of these values is very similar to that found in sclerosis multiplex (SM). There is a problem whether both clusters represents the same disorder of CNS compared with amyotrophic lateral sclerosis (ALS) or spinal muscular atrophy which have different values. Another problem is the participation of presumed central lesion on the increased jitter, the mechanism of which is still unknown.

Aged↗
PubMed1992

Tetanic syndrome and its examination.

The article presents a new electromyographic method; it describes the non-invasive examination of tetany with surface electrodes. This method is more sensitive than the classical needle technique and, moreover, the necessity to use expensive disposable needle electrodes is avoided.

Electromyography↗
PubMed1990

Biodegradation of polyethylene foils by bacterial and liver homogenates.

The evaluation of structural changes of single linear and bifurcated polyethylene foils exposed to bacterial and liver homogenates was carried out by infrared spectrography, along with observations of changes of mechanical properties. Cell homogenates were fractionated by centrifugation and by coagulating the microsomal fraction using Ca2+ ions. Stimulation as well as inhibition of the presumed enzyme system were studied in bacterial cultures and liver homogenates of experiment animals. Results suggest that oxidation structures in polyethylene, after exposure to these cell homogenates, are caused by the monooxygenase hydroxylation system of the bacterial or liver cells.

Animals↗
PubMed1990

Effect of cytochrome P-450 inhibition and stimulation on intensity of polyethylene degradation in microsomal fraction of mouse and rat livers.

Polyethylene (PE) is degraded in microsomal fractions of mouse and rat livers with the formation of carbonyl groups. Infrared spectroscopy demonstrated formation of predominantly ketone groups and to a lesser degree ester and aldehyde groups. The inhibition and stimulation of cytochrome P-450 in mouse livers affected the formation of oxidative groups on PE. Phenobarbital doses of 3 x 0.05 mg per mouse increased the concentration of cytochrome P-450 and ketone groups on PE, whereas the vaccine Propionibacterium acnes (0.5 mg) and its pyridine fraction (0.5 and 1 mg) had the opposite effect. The coherence of cytochrome P-450 with oxidative changes on PE is compared and discussed with findings on implants in man.

Animals↗