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J Rubes

Publications and source records attributed to J Rubes.

At least 19 recordsLinked to original sources
PubMed2006

Cytogenetic characterization of alpaca (Lama pacos, fam. Camelidae) prometaphase chromosomes.

The present study provides specific cytogenetic information on prometaphase chromosomes of the alpaca (Lama pacos, fam. Camelidae, 2n = 74) that forms a basis for future work on karyotype standardization and gene mapping of the species, as well as for comparative studies and future genetic improvement programs within the family Camelidae. Based on the centromeric index (CI) measurements, alpaca chromosomes have been classified into four groups: group A, subtelocentrics, from pair 1 to 10; group B, telocentrics, from pair 11 to 20; group C, submetacentrics, from pair 21 to 29; group D, metacentrics, from pair 30 to 36 plus sex chromosomes. For each chromosome pair, the following data are provided: relative chromosome length, centromeric index, conventional Giemsa staining, sequential QFQ/C-banding, GTG- and RBG-banding patterns with corresponding ideograms, RBA-banding and sequential RBA/silver staining for NOR localization. The overall number of RBG-bands revealed was 391. Nucleolus organizer-bearing chromosomes were identified as pairs 6, 28, 31, 32, 33 and 34. Comparative ZOO-FISH analysis with camel (Camelus dromedarius) X and Y painting probes was also carried out to validate X-Y chromosome identification of alpaca and to confirm close homologies between the sex chromosomes of these two species.

Animals↗
PubMed2005

Embryos produced in vitro from bulls carrying 16;20 and 1;29 Robertsonian translocations: efficiency and kinetics of oocyte fertilization and embryo development.

The present experiments were designed to study the effects of Robertsonian translocations on the efficiency and kinetics of in vitro fertilization and early and advanced embryo development. Spermatozoa from bulls with rob(16;20), rob(1;29) and normal karyotype (A, B and C, respectively) were used. Oocytes were matured, fertilized and cultured by the standard protocol described previously. Twenty-four hours after fertilization, adequate numbers of oocytes were fixed, stained and examined. The development of embryos was evaluated on days 2 (D2), 7 (D7) and 8 (D8) after fertilization. The rate of normally fertilized oocytes was significantly lower (p < or = 0.01) for bull A than for bulls B and C. However, no significant differences in the kinetics of fertilization were found between bulls A, B and C. The D2 cleavage rate of embryos was significantly lower (p < or = 0.01) for bull A than for bulls B and C. Both D7 and D8 blastocyst rates for bull A or bull B were significantly lower (p < or = 0.01 or p < or = 0.05) than those for bull C. The percentages of both D7 advanced blastocysts and D8 expanded blastocysts were significantly lower (p < or = 0.01) for bulls A and B than for bull C. In conclusion, for rob(16;20), the efficiency of fertilization was strongly reduced; it resulted in low early and advanced embryo development. On the other hand, for the rob(1;29), neither fertilization nor early embryo development were affected and only advanced embryo development was decreased. But for both translocations, blastocyst formation was significantly delayed.

Analysis of Variance↗
PubMed2005

Cytogenetic mapping of immunity-related genes in the domestic horse.

Chromosomal locations of 19 horse immunity-related loci (CASP1, CD14, EIF5A, FCER1A, IFNG, IL12A, IL12B, IL12RB2, IL1A, IL23A, IL4, IL6, MMP7, MS4A2, MYD88, NOS2A, PTGS2, TFRC and TLR2) were determined by fluorescence in situ hybridization. For IFNG and PTGS2, this study is a confirmation of their previously reported position. In addition, microsatellite (HMBr1) was localized in the same region as IFNG. All genes were assigned to regions of conserved synteny and the data obtained in this study enhance the comparative human-horse map. Cytogenetic localization of IL6 to ECA4q14-q21.1 suggested a new breakage point that changes the order of loci compared with HSA7. The map assignments of these loci serve as anchors for other loci and will aid in the search for candidate genes associated with traits in the horse.

Animals↗
PubMed2005

Individual variation in the frequency of sperm aneuploidy in humans.

To examine interindividual differences in sperm chromosome aneuploidy, repeated semen specimens were obtained from a group of ten healthy men, aged 20-21 at the start of the study, and analyzed by multi-color fluorescence in situ hybridization (FISH) analysis to determine the frequencies of sperm aneuploidy for chromosomes X, Y, 8, 18 and 21 and of diploidy. Semen samples were obtained three times over a five-year period. Statistical analysis examining the stability of sperm aneuploidy over time by type and chromosome identified two men who consistently exhibited elevated frequencies of sperm aneuploidy (stable variants): one with elevated disomy 18 and one with elevated MII diploidy. Differences among frequencies of aneuploidy by chromosome were also seen. Overall, disomy frequencies were lower for chromosome X, 8 and 18 than for chromosomes 21 or Y and for XY aneuploidy. The frequency of chromosome Y disomy did not differ from XY sperm frequency. Also, the frequency of meiosis I (XY) and II (YY + XX) sex chromosome errors did not differ in haploid sperm, but the frequency of MII errors was lower than MI errors in diploid sperm. Frequencies of sperm aneuploidy were similar between the first sampling period and the second, two years later. However, the frequency of some types of aneuploidy (XY, disomy Y, disomy 8, total autosomal disomies, total diploidy, and subcategories of diploidy) increased significantly between the first sampling period and the last, five years later, while others remained unchanged (disomy X, 21 and 18). These findings confirm inter-chromosome differences in the frequencies of disomy and suggest that some apparently healthy men exhibit consistently elevated frequencies of specific sperm aneuplodies. Furthermore, time/age-related changes in sperm aneuploidy may be detected over as short a period as five years in a repeated-measures study.

Adult↗
PubMed2003

Aneuploidy detection in porcine embryos using fluorescence in situ hybridization.

In contrast to human embryos, there are very few studies published on the frequency of chromosomal aneuploidy in farm animals. The objectives of this study were to apply a three-color fluorescent in situ hybridization (FISH) method for evaluating aneuploidy in porcine embryos using chromosome-specific DNA probes, establish baseline frequencies of aneuploidy in embryos and compare the results with our previous findings of aneuploidy in spermatozoa and oocytes. The embryos were collected from superovulated gilts, which were slaughtered 48 h after insemination. FISH was performed using probes specific for the centromeric regions of porcine chromosomes 1, 10 and Y. Altogether 403 blastomeres from 114 porcine embryos were successfully investigated. Diploidy was observed in 101 (88.6%) embryos, triploidy in 2 (1.8%) embryos, mosaicism/mixoploidy in 9 (7.9%) embryos, and trisomy for chromosomes 1 or 10 in 2 (1.8%) embryos. No blastomere showed aneuploidy for chromosome Y. These findings correspond with the frequencies of aneuploidy we have found previously in porcine germ cells.

Aneuploidy↗
PubMed2003

[Preimplantation genetic diagnosis (PGD) of chromosomal aberrations using the fluorescence in situ hybridization method (FISH)--introduction to problems, sampling methods and examination techniques].

OBJECTIVE: Presentation of preimplantation genetic diagnosis and the set of laboratory processes like aspiration, preparation and evaluation of polar bodies, sperm cells and blastomeres using FISH method (fluorescent in situ hybridization) in ART. DESIGN: Review. SETTING: Sanatorium REPROMEDA, Brno, Veterinary Research Institute, Brno. METHODS: Overview of published data and own clinical experience with the cell aspiration methods, evaluated sample preparation and the proper chromosomes visualisation using FISH method. CONCLUSION: The review brings an overview of conditions and methods including sample obtaining, FISH analysis preparation and implementation, processed during PGD.

Chromosome Disorders↗
PubMed2002

Assignment of porcine cyclin-dependent kinase 4 (CDK4) and oncogene c-mos (MOS) by nonradioactive nonfluorescence in situ hybridization.

Two pig genes, cyclin-dependent kinase 4 (CDK4) and the oncogene c-mos (MOS) were mapped by means of nonradioactive nonfluorescence in situ hybridization. Our approach was based on the detection of hybridized biotinylated probe by peroxidase conjugated extravidin and the reaction of peroxidase with its substrate diaminobenzidine (DAB) resulting in a dark precipitate. To increase the sensitivity of the method in single-copy gene mapping, two amplifications of the peroxidase signal were used: immunological amplification by biotinylated antiavidin, and peroxidase-catalysed deposition of biotinylated tyramide. Using this method, two 2-kb-long probes for the porcine genes CDK4 and MOS were mapped to pig chromosomes 5p12 and 4q14-15, respectively. Non-radioactive nonfluorescence in situ hybridization described here is a method of choice for gene mapping of short probes.

3,3'-Diaminobenzidine↗
PubMed2002

Characterization of the NRAMP1 (SLC11A1) gene in the horse (Equus caballus L.).

The complete coding cDNA sequence of the horse NRAMP1 (SLC11A1) gene was determined (GenBank accession number AF354445). The nucleotide sequence of the horse NRAMP1 gene is similar to sequences of this gene in other species. The gene contains 15 exons whose total length of 1,635 bp corresponds to 544 amino acids constituting the resulting putative protein. Hydrophobicity profile analysis of the deduced horse NRAMP1 gene product showed a nearly identical structure with the mouse NRAMP1 protein. The gene was found to be located on the short arm of ECA 6p12-13 by fluorescence in situ hybridization (FISH) analysis. Five allelic variants of the 5' untranslated region (UTR) were identified at the nucleotide sequence level. PCR-RFLP polymorphisms for NlaIII, TaqI, MspI and AciI were detected. Four out of five alleles could be detected using TaqI and MspI restriction enzymes. Their haplotype frequencies were different in four genetically distinct horse breeds.

5' Untranslated Regions↗
PubMed2001

Frequency of aneuploidy in pig oocytes matured in vitro and of the corresponding first polar bodies detected by fluorescent in situ hybridization.

The objectives of this study were to develop a two-color fluorescent in situ hybridization (FISH) method for evaluating aneuploidy in gilt oocytes using chromosome-specific DNA probes, and to establish baseline frequencies of aneuploidy in pig oocytes matured in vitro. The ovaries were collected from gilts at the local slaughterhouse. Immature oocytes were isolated by slicing the cortex of the ovaries. The oocytes were matured in microplate wells using TCM-199 medium supplemented with 10% estrous cow serum, sodium pyruvate, antibiotics, and gonadotrophins. After 44 h of maturation the oocytes were incubated with hyaluronidase and the cumulus cells were removed by vortexing. Single oocytes were transferred into 1 microL drops of a lysing buffer (0.01 N HCl/0.1% Tween 20) on clean microscopic slides. Two-color FISH was performed using probes specific for Chromosomes 1 and 10. The probe for Chromosome 1 was labeled with Cy3-dUTP and a probe labeled with fluorescein-11-dUTP was used for Chromosome 10. Only oocytes in which a complementary first polar body was found were confirmed as aneuploid. The final assessment of aneuploidy was based on results of 1189 haploid oocytes. Thirty-four (3%) of the examined oocytes were aneuploid. Disomy of Chromosome 1 and Chromosome 10 was found in 12 of 34 and 8 of 34 of the aneuploid oocytes, respectively. Nullisomy of Chromosome 1 and Chromosome 10 was found in 8 of 34 and 6 of 34 of the aneuploid oocytes. No significant differences were found in the frequencies of disomies and nullisomies of oocytes or in the frequencies of aneuploidies of Chromosomes 1 and 10. The frequency of aneuploid oocytes determined by FISH seems to be higher than that determined by conventional methods in other laboratories.

Aneuploidy↗