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I Chudoba

Publications and source records attributed to I Chudoba.

23 records · Page 2Linked to original sources
PubMed1996

Additional copies of a 25 Mb chromosomal region originating from 17q23.1-17qter are present in 90% of high-grade neuroblastomas.

Neuroblastoma shows remarkable heterogeneity, ranging from spontaneous regression to progression toward highly malignant tumors. In search of genetic abnormalities that could explain this variability, we have characterized neuroblastoma tumors by using multiple fluorescent hybridizations. Our results indicate that chromosome 17 is rearranged very frequently in the form of unbalanced translocations with numerous chromosomal partners, all leading to the presence of supernumerary copies of a 25 Mb chromosomal region originating from 17q23.1-qter. Additional 17q material was detected in more than 90% of untreated high-grade neuroblastomas and, along with 1p36 deletion, should represent the most frequent genetic abnormality of neuroblastoma observed until now.

Blotting, Southern↗
PubMed1992

Cytogenetic abnormalities in a rare case of giant cell osteogenic sarcoma.

The cytogenetic analysis of a rare, nonirradiated case of giant cell tumor of bone with osteogenic sarcoma transformation is presented for the first time in a 19-year-old female. Telomeric associations involving 4p, 8p, 11p, 14p, 17p, 17q, and 20q were observed. Additionally, monosomy 13, 11p abnormalities and marker chromosomes were identified in tumor cells. Chromosome 11 involvement, particularly 11p translocations and 11p telomeric associations, were frequently observed in the tumor cells obtained from our patient, which suggests that chromosome 11p may play a role in the development of giant cell osteogenic sarcoma.

Adolescent↗
PubMed1989

Investigations of chorionic villi after chorionic villus sampling (CVS). Correlation of morphological with clinical and laboratory data.

This report documents the first 262 cases of chorionic villus sampling (CVS) performed in parallel with cytogenetic and morphological investigations. Histomorphological examination of these CVS specimens gave suitable results in about 96% (251 cases). Of the latter, 201 samples (80.1%) exhibited villi and 176 (70.1%), maternal tissue. Viability and maturation of the chorionic villi were determined light microscopically even in cases with few villus trees. Smooth avascular villi with poorly defined margins observed under an inverted microscope, less than 10 mitoses after short-term incubation, and reduced growth of cell cultures were significantly correlated with sampling at the chorion laeve by means of histomorphologic criteria. Villi from cases exhibiting cytogenetically proved chromosomal abnormalities were characterized by molar degeneration or stromal fibrosis, or both, in 4 out of 9 cases, including 3 mosaics. In early abortions (within 3 weeks after CVS), an unexpectedly high rate of pathohistological changes within maternal tissue was evident. These results need further confirmation by investigation of a greater number of samples with immunohistochemical and morphometric methods.

Adult↗
PubMedDate not supplied

Microdissection and reverse painting reveals a microdeletion 6(q26qter) in a de novo r(6) chromosome.

Ring chromosomes 6 are rare constitutional abnormalities with inconsistent phenotypic and clinical features. One of the reasons for this variability is the cytogenetically undetectable loss of chromosomal material from the telomeric segments at 6p or 6q. We have therefore used fluorescence in situ hybridization (FISH) to analyse a ring chromosome 6 that was detected in a newborn boy with dysmorphic features. Reverse painting of the microdissected ring chromosome onto normal metaphase spreads revealed a small deletion of the terminal region of the long arm, 6(q26qter). Moreover, the simple all-telomeric sequence (TTAGG)n was lost, whereas the p-specific subtelomeric sequence was still present. Our findings confirm that microdeletions occur during the formation of r(6) chromosomes and, therefore, are an important determinator of the associated phenotype.

Adult↗