Genomic damage in children accidentally exposed to ionizing radiation: a review of the literature.

During the last decade, our knowledge of the mechanisms by which children respond to exposures to physical and chemical agents present in the environment, has significantly increased. Results of recent projects and programmes focused on children's health underline a specific vulnerability of children to environmental genotoxicants. Environmental research on children predominantly investigates the health effects of air pollution while effects from radiation exposure deserve more attention. The main sources of knowledge on genome damage of children exposed to radiation are studies performed after the Chernobyl nuclear plant accident in 1986. The present review presents and discusses data collected from papers analyzing genome damage in children environmentally exposed to ionizing radiation. Overall, the evidence from the studies conducted following the Chernobyl accident, nuclear tests, environmental radiation pollution and indoor accidental contamination reveals consistently increased chromosome aberration and micronuclei frequency in exposed than in referent children. Future research in this area should be focused on studies providing information on: (a) effects on children caused by low doses of radiation; (b) effects on children from combined exposure to low doses of radiation and chemical agents from food, water and air; and (c) specific effects from exposure during early childhood (radioisotopes from water, radon in homes). Special consideration should also be given to a possible impact of a radiochemical environment to the development of an adaptive response for genomic damage. Interactive databases should be developed to provide integration of cytogenetic data, childhood cancer registry data and information on environmental contamination. The overall aim is to introduce timely and efficient preventive measures, by means of a better knowledge of the early and delayed health effects in children resulting from radiation exposure.

Chromosomal abnormalities and DNA image cytometry of haematological neoplasms in fine needle aspirates of lymph nodes.

The current diagnostics of haematological neoplasms along with morphological analysis, immunophenotyping and molecular analysis inevitably includes cytogenetic analysis. In this work the possibility of cytomorphological subclassification of haematological neoplasms from lymph node fine needle aspirates was examined without depending upon the referential histological diagnosis and cytogenetic analysis. In addition, the feasibility of cytogenetic analysis of the material obtained by lymph node fine needle aspiration (FNA) was examined. By analysing the findings of cytogenetic analysis and DNA image cytometry, it was decided to examine the possibility of comparing the findings and supplementing diagnostic possibilities of these methods. In 15 cases cytological diagnoses and cytogenetic analysis of haematological neoplasms were performed on the material obtained by lymph node FNA. In 12 of 15 cases histological diagnosis was made separately. A good cytohistological correlation was available in 9 of 12 cases (75%). Cytomorphological diagnoses in 10 of 15 cases (76%) were confirmed by the finding of a specific chromosomal translocation. In two cases cytological diagnosis did not correlate with the histological diagnosis and was confirmed only with specific chromosomal translocations. The lymphocytes obtained by lymph node FNA were adequate material for cytogenetic analysis - in 15 of 18 (83%) cases mitoses in cell cultures were obtained. In 13 of 15 (87%) cases clonal chromosomal abnormalities were detected, whereas in 2 of 15 (13%) cases a normal karyotype was found. DNA image cytometry was performed on nine samples, whereas in six samples the material was not sufficient. Although a small number of samples was analysed in the cases with identical cytomorphological diagnoses, the analysed histograms regarding the DNA index values showed heterogeneity. In conclusion, a cell culture sampled by FNA of lymph nodes is an adequate method for the chromosomal analysis. The specific cytogenetic abnormality associated with cytological diagnosis provides an opportunity to make a definitive diagnosis and provides a powerful approach when reference diagnosis on biopsy material cannot be obtained.

[The usefulness of the chorionic villi technic in prenatal diagnosis]. / Korisnost korion frondozum tehnike u prenatalnoj dijagnozi.

The chorion frondosum technique was performed, after a pilot study, in 33 early pregnancies (1986-1988). The procedure was carried out between the 8th and the 12th week of pregnancy, and the indications were the gravida's age, chromosomal abnormality in parents and in the child previously born in the family, and sex-linked disease. Out of 33 cultures examined after transcervical CF biopsy, 11 were confirmed also by the findings of early amniocentesis. The method of Siloni et al. was applied to chorion frondosum cells, both by direct and indirect cultivation: 28 of the total of 33 cultures were successful, while 5 failed. Three fetuses, one with balanced translocation and two normal ones, were spontaneously aborted in the first two weeks following the procedure. Three fetuses were aborted due to medical indication, two translocation forms of DS with the mother carrier of t 21/21 and one translocation form of Sy. Patau with the mother having mixoploidy 46; XX/45,XX,t(13q;13q). So far nine children of the predicted kariotype and sex have been born and their development is normal. The course of the remaining pregnancies is also normal, except for one with the spontaneous abortion in the 24th week.