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Amplification of c-MYCand MLLGenes as a Marker of Clonal Cell Progression in Patients with Myeloid Malignancy and Trisomy of Chromosomes 8 or 11Gene amplification (amp) is one of the basic mechanisms connected with overexpression of oncogenes. The c-MYC(located in 8q24) and MLL(located in 11q23) are the most often over represented genes that lead to a rapid proliferation of the affected cell clone in patients with myeloid neoplasms. Assessment of the level of amp c-MYCor amp MLLin the cases with trisomy 8 (+8) or trisomy 11 (+11) and myeloid malignances is necessary for a more precise estimation of the disease progression.A total of 26 patients with acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) were included in the study: 18 with +8, six with +11 and two with complex karyotypes suspected of the partial trisomy. Routine cytogenetic analysis and fluorescent in situhybridization (FISH) were applied to indicate the chromosome alterations and genes ampin the bone marrow cells.Amp c-MYCwas observed in 12 from 18 (66.7%) patients with +8. All the patients with +11 demonstrated a different level of amp MLL. In most of the cases with MDS (9/10), the coincidence of the +8 or +11 with amp c-MYCor amp MLL, respectively, leads to transformation to AML and/or short overall survival. Our data suggest that amp c-MYCand amp MLLdevelop in conformity with +8 and +11, especially in cases with progressive deviations in the karyotype as an aggressive expansion of an aberrant cell clone and appearance of additional chromosome anomalies.

An analysis of electrocardiographic pattern recognition parameters for premature ventricular contraction (PVC) and normal (N) beat classification is presented. Twenty-six parameters were defined: 11 × 2 for the two electrocardiogram (ECG) leads, width of the complex and three parameters derived from a single-plane vectorcardiogram (VCG). Some of the parameters include amplitudes of maximal positive and maximal negative peaks, area of absolute values, area of positive values, area of negative values, number of samples with 70% higher amplitude than that of the highest peak, amplitude and angle of the QRS vector in a VCG plane. They were measured for all heartbeats annotated as N or PVC in all 48 ECG recordings of the MIT-BIH arrhythmia database. Two reference sets for the Kth nearest-neighbours rule were used-global and local. The classification indices obtained with the global reference set were 75.4% specificity and 80.9% sensitivity. Using the local reference set we increased the specificity to 96.7% and the sensitivity to 96.9%. The achieved specificity and sensitivity are comparable with, and greater than, the results reported in the literature.

The propagation of light pulses with partial spatial and temporal coherence is analysed. It is shown that the introduction of the second-order coherence function enables the description of both spatial and temporal radiation characteristics to be described in the angular spectrum approach. A strong correlation between the spatial and temporal parameters is obtained.

A configuration with dispersive properties, consisting of gratings and lenses is proposed. It is shown that such a scheme allows one to achieve simultaneously both positive and negative group velocity dispersion. It has lens-like properties in time and can be considered as a compound 'time lens', assembled by positive and negative 'time lenses'. A promising application in the form of a device for 'magnification' of light pulses is also illustrated.

A theoretical analysis of an optical processing system for time-space shaping of short light pulses is presented. The optical scheme considered consists of two gratings with a 4-f Fourier-processing system placed between them. Using an expansion of the field over a set of temporal and spatial modes, we find an expression for the output field as a function of the input field and of the system parameters. Our approach allows the solving of the inverse problem: a determination of the filter function, which will give a preliminary designed output pulse shape. The formalism developed could be applied in the description of other similar systems.

An amplifier scheme which allows control of the spectrum of the amplified pulse is proposed. The spectral components of the initial pulse are sent into laterally shifted regions of the amplifying medium, which enables control of the gain of particular frequency components. By the use of a properly formed pump, spectral narrowing during amplification can be avoided. A 'spectrum preserving' amplification of ultra-broadband (f.w.h.m. of about 30 nm) nanosecond pulses is demonstrated.