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M Kubat

Publications and source records attributed to M Kubat.

9 recordsLinked to original sources

A study of the short tandem repeat systems HUMVWA and HUMTH01 in an Austrian population sample.

The genotype distributions for the short tandem repeat systems (STRs) HUMVWA and HUMTH01 have been studied in 128 unrelated Caucasians fromêAustria. The allelic distributions were in accordance with Hardy-Weinberg expectations. The heterozygosities were 0.82 and 0.81, whereas the mean exclusion chance was 0.62 and 0.55, respectively. In one person, a VWA-allele consisting of 11 repeats was found.

Austria

Population genetic study from the Zagreb area using 3 STR systems.

Population genetic studies were carried out on Caucasians from north-west Croatia (Zagreb-area) using the short tandem repeat (STR) systems HumTHO1, HumVWA and HumACTBP2. After electrophoresis in PAG, 6 alleles could be identified for HumTHO1 in a sample size of 100 unrelated individuals and 7 alleles were found for VWA. For ACTBP2, 25 alleles have been identified. No significant deviations from Hardy-Weinberg equilibrium could be observed.

Alleles

AI-based approach to automatic sleep classification.

The primary goal of this paper is to introduce the potential of artificial intelligence (AI) methods to researchers in sleep classification. AI provides learning procedures for the construction of a sleep classifier, prescribing how to combine the observed parameters and how to derive the corresponding decision thresholds. A case study reporting a successful application of an automatic induction of decision trees and of a learning vector quantizer to this domain is presented.

Artificial Intelligence

Towards automated sleep classification in infants using symbolic and subsymbolic approaches.

The paper addresses the problem of automatic sleep classification. A special effort is made to find a method of extracting reasonable descriptions of the individual sleep stages from sample measurements of EGG, EMG, EOG, etc., and from a classification of these measurements provided by an expert. The method should satisfy three requirements: classification accuracy, interpretability of the results, and the ability to select the relevant and discard the irrelevant variables. The solution suggested in this paper consists of a combination of the subsymbolic algorithm LVQ with the symbolic decision tree generator ID3. Results demonstrating the feasibility and utility of our approach are also presented.

Algorithms

Gangliosides in the human brain development and aging.

In this study, brain gangliosides in prenatal and postnatal human life were analyzed. Immunohistochemically, the presence of "c"-pathway of gangliosides (GQ1c) in embryonic brain was only recorded at 5 weeks of gestation. Biochemical results indicated a twofold increase in human cortex ganglioside concentration between 16 and 22 weeks of gestation. The increasing ganglioside concentration was based on an increasing GD1a ganglioside fraction in all regions analyzed except cerebellar cortex, which was characterized by increasing GT1b. In this developmental period, GD3 was found to be localized in the ventricular zone of the cortical wall. After birth, GD1b ganglioside in neuropil of granular cell layer corresponding to growing mossy fibers was expressed in cerebellar cortex. Between birth and 20/30 years of age, a cerebral neocortical difference of ganglioside composition was observed, characterized by lowest GD1a in visual cortex. Analyzing the composition of gangliosides in cortical regions during aging, they were observed to follow region-specific alterations. In frontal cortex, there was a greater decrease in GD1a and GM1 than in GT1b and GD1b, but in occipital (visual) cortex there was no change in individual gangliosides. In hippocampus, GD1a moderately decreased, whereas other fractions were stable. In cerebellar cortex, GD1b and GT1b fractions decreased with aging.

Abortion, Legal

Structural basis of the developmental plasticity in the human cerebral cortex: the role of the transient subplate zone.

We correlated neuroanatomical developmental parameters with sequential ultrasonography scans to reveal the structural basis of functional recovery after early focal hypoxic lesions of the human frontal lobe in premature infants. We studied the transient fetal subplate zone in the premotor and prefrontal cortex in premature, newborn, infant, and young adult brains by acetylcholinesterase (AChE) histochemical, Golgi, and immunocytochemical methods. The structural in vivo rearrangements of the cerebral wall after perinatal lesions were studied on serial real-time sector scans (5-MHz transducer). The subplate zone contains "waiting" axons and randomly oriented fetal neurons, its developmental peak is between 22 and 34 weeks of gestation, and it is present in the frontal cortex of newborns and disappears after the sixth postnatal month, but individual subplate-like neurons remain until adulthood. Ultrasonography revealed remarkable structural rearrangements of the cerebral wall when the hypoxic lesion occurred during the developmental peak of the subplate zone: anechoic cavities ("cysts") develop rapidly (within 3 weeks) in premature brains, the rebuilding of these lesions continues after birth, and cavities disappear around the 11th month. We propose that the transient population of "waiting" axons and cells of the subplate zone participate in the structural and functional plasticity of the human cerebral cortex after perinatal brain damage.

Adult

[Gangliosides in the serum in lung carcinoma].

In this study, tumor and serum gangliosides were analyzed in patients bearing lung planocellular carcinoma (LPC) before and after operative therapy. Tumor tissue, pathohistologically characterized as carcinoma planocellulare corneum (Ca. epidermoide, type 8070/3, WHO, Geneva, 1981), showed an elevated concentration of gangliosides in comparison to normal tung tissue. The composition of gangliosides in LPC tissue varied from one tumor sample to another, however, two general features were observed. First, LPC contained an increased amount of GM3 and a decreased amount of GD3 gangliosides. Second, an elevated proportion of gangliosides migrating as polysialogangliosides (x3, x5, x6) characterized the majority of LPC tissues. On the other hand, serum of patients with LPC contained an elevated amount of gangliosides (15.8 +/- 0.3 mumols/L) in comparison to control serum (6.1 +/- 0.8 mumols/L) (P less than 0.01). However, analyzing the composition of serum gangliosides by thin-layer chromatography, all serum gangliosides were more or less elevated. By day 21 after the surgical removal of LPC, serum gangliosides dropped by approximately 50% approaching the normal values. It seems that elevated serum gangliosides in LPC patients were secreted from carcinoma cells, because they normalized after surgical removal of LPC. Thus, serum gangliosides might be a useful biochemical tool for diagnosis and therapy monitoring of this carcinoma.

Carcinoma