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Biomedical subjects

J Melnyk

Publications and source records attributed to J Melnyk.

11 recordsLinked to original sources
PubMed1976

Karyotype analysis by computer and its application to mutagenicity testing of environmental chemicals.

Large scale population monitoring by cytogenetics would require vast amounts of effort for meaningful results. Computer techniques promise to assume some of this burden and thus render large scale monitoring a more practical alternative than it is now. A system recently developed at the California Institute of Technology, Jet Propulsion Laboratory and the City of Hope Medical Center, contains many of the features required by a large scale population monitoring system. One part of the system is a semi-automated slide preparation assembly which can process up to 576 specimens per day with uniform treatment. The second part of the system consists of a computer-controlled microscope which performs automatic slide search, metaphase location, and karyotype analysis under the interactive supervision of an operator. While the system was developed primarily for clinical cytogenetics, some aspects of our operating experience suggest promising approaches for population cytogenetics.

Chromosome Aberrations↗
PubMed1968

Nonrandomness of translocations in man: preferential entry of chromosomes into 13-15-21 translocations.

Lymphocytes from 20 individuals with Down's syndrome due to 13-15/21 centric-fusion translocations were studied by autoradiography after continuous late labeling with tritiated thymidine. In no case was chromosome 13 involved; chromosome 14 was involved in 18 cases, and chromosome 15 in two cases. These results are similar to those from 13 previously studied cases and indicate that the entry of chromosomes 13-15 into translocations is nonrandom. This nonrandomness is not a simple function of chromosome size or shape, since chromosomes 13-15 are acrocentrics of similar size.

Autoradiography↗