This study was performed to investigate the toxicity of ochratoxin A (OA) to the chromosomes of K562 tumor cell-line in vitro. Chromosomes of K562 tumor cell-line resulted in pseudotriploidy on the control group. Chromosomes of K562 tumor cell-line treated with OA resulted in heteroploidy compared with the control group. The mean number of chromosomes in the karyotype of the control group (60) were 7 in the A group, 5 in the B group, 20 in the C+X group, 7 in the D group, 9 in the E group, 6 in the F group, and 6 in the G+Y group respectively. Treating with 0.7 micro M OA, the number of chromosomes were increased one in E and F group, two in G+Y group compared with control group. In treated with 1.5 micro M OA, the increasing number of chromosome was one in E and F group. In treated with 3 micro M OA, E and F group was increased one and G+Y group were increased two chromosome in G+Y group was decreased one. K562 tumor cell line treated with OA showed Philadelphia-Chromosome in the long arm of the G group karyotype chromosome. The rate of chromosome aberration in K562 tumor cell-line treated with OA was 77 % in 0.7 micro M OA group, 71 % in 1.5 micro M OA group, 82 % in 3 micro M OA group and 94 % in 6 micro M OA group respectively. The rate of chromosome aberration of K562 tumor cell-line treated with OA was high in the high dose level of OA, and chromosome aberration of K562 tumor cell-line treated with OA showed deletion, minute, dicentric-chromosome and translocation in the long arm of the C-group karyotype. As a result of this study, the toxicity of OA showed deletion, minute, dicentric-chromosome and translocation in the long arm of the C-group karyotype, and then, the toxicity of OA resulted in the damage to RNA and protein synthesis in K562 tumor cell-line, and the C-group karyotype of K562 tumor cell-line was target of the toxicity of OA.

Introduction: Canine transmissible venereal tumour (CTVT) is a sexually transmitted tumour affecting dogs worldwide, imposing a financial burden on dog owners. A stable culture cell line in continuous passages for >18 months has only been achieved once. The present study investigated a stable CTVT cell line isolated from a bitch and its potential as a vaccine. Material and Methods: A biopsy from a 2-year-old mongrel bitch with CTVT was obtained for histopathological confirmation and isolation of tumour cells. The isolated cells were cultured to passage 55 and characterised by flow cytometry, with karyotyping by GTG-banding and by PCR detection of myc S-2 and LINE AS1. The isolated CTVT cell line was also used as a preventive vaccine in a canine model. Results: Histopathological analysis of the isolated tumour cells revealed typical CTVT characteristics. Constant proliferation and stable morphological characteristics were observed during culture. Phenotypic analysis determined the expression of HLA-DR⁺, CD5.1⁺, CD14⁺, CD45⁺, CD83⁺, CD163⁺, and Ly-6G-Ly-6C⁺. GTG-banding revealed a mean of 57 chromosomes in the karyotype with several complex chromosomal rearrangements. LINE-c-myc insertion in the isolated CTVT cell line at 550 bp was not detected. However, a 340-bp band was amplified. Isolated CTVT cell line inoculation at a concentration of 1×10⁸ did not induce tumour growth in bitches, nor did a challenge with primary CTVT cells. Conclusion: The present study successfully identified and isolated a stable CTVT cell line that may be useful in CTVT prevention.

Comparative analysis of the karyotype structure was made in two hedgehog species: the northern white-breasted hedgehog (Erinaceus roumanicus) and the African pygmy hedgehog (Atelerix albiventris). The cytogenetic analysis used differential staining techniques (DAPI, Ag-NOR, and C-banding/DAPI) and sequential QFQ/FISH banding with NOR20 and TEL20 probes which showed 45S rDNA and (TTAGGG)ₙ repeat sequences, respectively, on hedgehog chromosomes. It was confirmed that the somatic cells of the hedgehogs have a constant number of chromosomes (2n = 48,XY). Differences were observed in the NOR number between the species. NORs were identified on three autosome pairs in the northern white-breasted hedgehog and on only two pairs in the African pygmy hedgehog. Chromosome analysis by C-banding/DAPI showed large segments of heterochromatin rich in A-T pairs on three autosome pairs in both the northern white-breasted and African pygmy hedgehogs. The heterochromatin segments encompassed large fragments of the longer arm of chromosome pairs 13, 14 and 20. The (TTAGGG)ₙ repeat sequences on the hedgehog chromosomes were only observed in the terminal position of all the chromosomes in both species. Our observations provide new information on the level of diversity within the Erinaceidae family.

Introduction: The objective of the study was immunophenotypic and cytogenetic analysis of mesenchymal stem cells from equine bone marrow and foal umbilical cords during in vitro culture.Material and Methods: The mesenchymal stem cells were obtained from equine bone marrow of three horses and from foal umbilical cords of six foals. The cells were cultured in CO₂ incubators by standard procedure. Quantitative abnormalities of chromosomes, i.e. aneuploidy and polyploidy, and structural aberrations, i.e. breaks in chromosomes and chromatid, were taken into account during the study.Results: The results of cytogenetic analysis of equine bone marrow mesenchymal stem cells at the third and fourth passages indicated that the level of karyotype variability of these cells corresponded to the spontaneous level of karyotype variability typical of the peripheral blood lymphocytes of this species. Equine bone marrow contained several clones of stem cells that differed in the expression of specific nuclear markers characteristic of proliferating cells.Conclusion: Mesenchymal stem cells from foal umbilical cords during in vitro cultivation are characterised by quantitative abnormalities of the chromosomal apparatus.

The nucleotide sequence of a chromosomally encoded antigen-expressing gene of Borrelia coriaceae was determined and used as a target for the polymerase chain reaction (PCR). Two primer sets were designed specifying the amplification of 269- and 701-bp DNA fragments. Primer set I, producing the short amplicon, was tenfold more sensitive than primer set II. As little as 10 fg of purified B coriaceae DNA could consistently be detected. The PCR assays, containing controlled numbers of whole spirochetes, allowed detectable amplification of 2 to 10 organisms. An internal, nonradioactively labeled gene-specific probe verified specificity of the PCR amplicons. Neither primer set cross-reacted with other related spirochetes. This PCR assay was adapted and found suitable for identification of B. coriaceae in biological samples, such as blood and thymus. Evidence for presence of B. coriaceae in biological samples was not found in tissue samples obtained from experimentally infected cows and their fetuses. These data failed to establish a definite association between B. coriaceae and epizootic bovine abortion.

Random fragments of DNA were obtained from a cosmid library of Salmonella agona genomic DNA. from this library, 2 fragments were chosen and pooled to probe isolates of S typhimurium obtained during an episode of salmonellosis in a veterinary medical teaching hospital. Chromosomal DNA from the Salmonella isolates was digested with restriction endonucleases, and was probed with the random fragments of chromosomal DNA. This procedure resulted in a fingerprint pattern for each isolate. We found that the method permitted discrimination between isolates involved in the disease episode and S typhimurium obtained prior to the episode. We conclude that random fragments of chromosomal DNA are useful for fingerprinting isolates of S typhimurium. Analysis of plasmid DNA obtained from the isolates was not as useful. Some isolates found to be identical by restriction site analysis, had plasmids of different molecular weight. These results indicate that plasmid analysis may not be as useful a fingerprinting tool as previously reported.

Lymphocytes from 5 clinically normal lambs and 5 lambs affected with ovine hereditary chondrodysplasia (spider syndrome) were cultured, G-banded, and karyotyped. Fifty metaphase karyotypes and one heterogram were evaluated for chromosome number and morphologic features. All lambs had normal diploid (2n) chromosome numbers of 54,XX or 54,XY, and there were no apparent differences in the morphologic features of the chromosomes.

A pig rhabdomyosarcoma cell line (PRUM59) was established, and the immuno(histo)chemical and cytogenetic characterization of these cells was determined. At various swine farms in the Netherlands, pigs were observed that had solitary or multiple skin nodules, which were diagnosed as rhabdomyosarcomas. Cells of a tumor derived from a 3.5-week-old female pig were cultured for immunochemical and cytogenetic analyses. The cell line had characteristic features of undifferentiated muscle cells, similar to those observed in tumor tissue sections; they contained titin, a high-molecular weight protein specific for striated muscle, as dot-like aggregates and as filaments, desmin filaments and cross-striations, smooth muscle actin stress fibers, and vimentin filaments. The cells stained positively for striated muscle actin and tropomyosin as well. The immunohistochemical staining results were supported by results of immunoblotting experiments. Karyotyping of the cells revealed a deletion of a major part of Xq24-qter, a part of the long arm of 1 of the 2 X chromosomes. The other X chromosome and all autosomes appeared to be normal.