Über die Mittelpunktkurve und ihre Sonderfälle

Alle Sonderfälle der Mittelpunktkurve werden mit den zugehörigen Polkonfigurationen, Kreispunktkurven und Anordnungen der Lagen der bewegten Ebene zusammengestellt für die Fälle, daß vier Lagen endlich benachbart sind, daß zwei und daß drei von vier Lagen unendlich benachbart sind.All special cases of the center-point curve are put together with the corresponding pole-configurations, circle-point curves and arrangements of positions of the moved plane for the cases that four positions are finitaly separated, that two of four positions and that three of four positions are infinitesimally close

The hierarchically organized splitting of chromosomal bands for all human chromosomes

<p>Abstract</p> <p>Background</p> <p>Chromosome banding is widely used in cytogenetics. However, the biological nature of hierarchically organized splitting of chromosomal bands of human chromosomes is an enigma and has not been, as yet, studied.</p> <p>Results</p> <p>Here we present for the first time the hierarchically organized splitting of chromosomal bands in their sub-bands for all human chromosomes. To do this, array-proved multicolor banding (aMCB) probe-sets for all human chromosomes were applied to normal metaphase spreads of three different G-band levels. We confirmed for all chromosomes to be a general principle that only Giemsa-dark bands split into dark and light sub-bands, as we demonstrated previously by chromosome stretching. Thus, the biological band splitting is in > 50% of the sub-bands different than implemented by the ISCN nomenclature suggesting also a splitting of G-light bands. Locus-specific probes exemplary confirmed the results of MCB.</p> <p>Conclusion</p> <p>Overall, the present study enables a better understanding of chromosome architecture. The observed difference of biological and ISCN band-splitting may be an explanation why mapping data from human genome project do not always fit the cytogenetic mapping.</p

Automated detection of residual cells after sex-mismatched stem-cell transplantation – evidence for presence of disease-marker negative residual cells

<p>Abstract</p> <p>Background</p> <p>A new chimerism analysis based on automated interphase fluorescence in situ hybridization (FISH) evaluation was established to detect residual cells after allogene sex-mismatched bone marrow or blood stem-cell transplantation.</p> <p>Cells of 58 patients were characterized as disease-associated due to presence of a bcr/abl-gene-fusion or a trisomy 8 and/or a simultaneous hybridization of gonosome-specific centromeric probes. The automatic slide scanning platform Metafer with its module MetaCyte was used to analyse 3,000 cells per sample.</p> <p>Results</p> <p>Overall 454 assays of 58 patients were analyzed. 13 of 58 patients showed residual recipient cells at one stage of more than 4% and 12 of 58 showed residual recipient cells less than 4%, respectively. As to be expected, patients of the latter group were associated with a higher survival rate (48 vs. 34 month). In only two of seven patients with disease-marker positive residual cells between 0.1–1.3% a relapse was observed. Besides, disease-marker negative residual cells were found in two patients without relapse at a rate of 2.8% and 3.3%, respectively.</p> <p>Conclusion</p> <p>The definite origin and meaning of disease-marker negative residual cells is still unclear. Overall, with the presented automatic chimerism analysis of interphase FISH slides, a sensitive method for detection of disease-marker positive residual cells is on hand.</p

Determination of telomerase activity for differential analysis of multifocal renal cell carcinomas

Determination of telomerase activity for differential analysis of multifocal renal cell carcinomas. Secondary tumors are found in approximately 12 to 22% of all renal cell carcinoma, and their origin is currently unknown. To determine their potential for malignancy, we examined the telomerase activity of primary tumors and secondary lesions, and found that 86% of the lesions had an identical telomerase status as the related primary tumors, and thus probably share their malignancy potential