Search results for "Cytogenetic"
showing 10 items of 159 documents
Centromeric enrichment of LINE-1 retrotransposon in two species of South American monkeys Alouatta belzebul and Ateles nancymaae (Platyrrhini, Primat…
2022
LINE-1 sequences have been linked to genome evolution, plasticity and speciation; however, despite their importance, their chromosomal distribution is poorly known in primates. In this perspective, we used fluorescence in situ hybridization (FISH) to map LINE-1 probes onto two representative platyrrhine species, Aotus nancymaae (Cebidae) and Alouatta belzebul (Atelidae), both characterized with highly rearranged karyotypes, in order to investigate their chromosomal distribution and role and to better characterize the two genomes. We found centromeric enrichment of LINE-1 sequences on all biarmed and acrocentric chromosomes co-localized with heterochromatin C-positive bands. This distributio…
L’IMPIEGO DELLA MORFOMETRIA GEOMETRICA E IL CONTRIBUTO DELLA CITOGENETICA NELLO STUDIO DELLA TRIBÙ CERCOPITHECINI (ORDINE PRIMATES)
The tribe Cercopithecini is a large and colourful taxon of African primates. Together with the tribe Papionini, it belongs to the subfamily Cercopithecinae (Gray, 1821). Despite several studies carried on the present species of Cercopithecini (guenons and sister genera), up to date a strong and clear systematics is missing. The evolutionary relationships inside the tribe are controversial, as are the numbers of genera and species. This lack prevents our full comprehension of the evolution of the tribe. We decided to investigate the tribe Cercopithecini through the use of two methodologies: geometric morphometrics and cytogenetics. The geometric morphometric survey was conducted on 1126 cran…
Loss of heterozygosity at the short arm of chromosome 3 in renal‐cell cancer correlates with the cytological tumour type
1993
A majority of renal-cell tumours retain heterozygosity at the short arm of chromosome 3. To investigate possible histopathological differences between tumours with and without such losses, we compared loss of heterozygosity data from 51 tumours with 1 histological and 2 different cytological classifications of renal-cell tumour. Using the cytological classification of Thoenes et al., we only found tumours with loss of heterozygosity in these authors' clear-cell category. Possibly, only these tumours arise by a mechanism of double loss of a tumour-suppressor gene on 3p, non-clear-cell renal tumours having a different genetic background. Alternatively, deletions may occur in all subtypes, in …
Concentration-Dependent Protection by Ethanol Extract ofPropolis against γ
2011
[EN] Radioprotection with natural products may be relevant to the mitigation of ionizing radiation-induced damage in mammalian systems; in this sense, propolis extracts have shown effects such as antioxidant, antitumoral, anti-inflammatory, and immunostimulant. We report for the first time a cytogenetic study to evaluate the radioprotective effect, in vitro, of propolis against radiation-induced chromosomal damage. Lymphocytes were cultured with increasing concentrations of ethanol extract of propolis (EEP), including 20, 40, 120, 250, 500, 750, 1000, and 2000 ¿g mL-1 and then exposed to 2 Gy ¿-rays. A significant and concentration-dependent decrease is observed in the frequency of chromoso…
Mapping the Wolf-Hirschhorn (wp 4p16.3) Locus on non-human primates
2008
MOLECULAR CYTOGENETIC APPROACH BY WOLF-HIRSCHHORN PROBE-MAPPING AND OTHERS BAC PROBES TO STUDY GENOME EVOLUTION IN PRIMATES
2009
Clinical application of embryo aneuploidy testing by next-generation sequencing
2019
Abstract We review here the evolution in the field of embryo aneuploidy testing over the last 20 years, from the analysis of a subset of chromosomes by fluorescence in situ hybridisation to the transition toward a more comprehensive analysis of all 24 chromosomes. This current comprehensive aneuploidy testing most commonly employs next-generation sequencing (NGS). We present our experience in over 130 000 embryo biopsies using this technology. The incidence of aneuploidy was lower in trophectoderm biopsies compared to cleavage-stage biopsies. We also confirmed by NGS that embryo aneuploidy rates increased with increasing maternal age, mostly attributable to an increase in complex aneuploid …
Frequency of dicentrics and contamination levels in Ukrainian children and adolescents from areas near Chernobyl 20 years after the nuclear plant acc…
2013
International audience; Purpose To survey the possible presence of chromosomal damage and internal contamination in a group of Ukrainian children and adolescents, 20 years after the Chernobyl accident at the Nuclear Power Plant. Materials and methods Cytogenetical procedures were performed according to dicentric assay in 55 Ukrainian children and adolescents (29 boys and 26 girls), living near Chernobyl. In addition, a whole body detector and urinalysis were used to detect internal contamination. Results 36 dicentrics were found in a total of 53,477 metaphases scored in these children, which reflected a frequency of dicentrics below the background level. On the other hand, internal contamin…
Clinical significance of complex karyotype at diagnosis in pediatric and adult patients with de novo acute promyelocytic leukemia treated with ATRA a…
2019
Although additional cytogenetic abnormalities (ACA) do not affect the prognosis of patients with t(15;17) acute promyelocytic leukemia (APL), the role of a complex karyotype (CK) is yet to be clarified. We aimed to investigate the relationship of CK with relapse incidence in 1559 consecutive APL patients enrolled in three consecutive trials. Treatment consisted of AIDA induction followed by risk-adapted consolidation. A CK (CK) was defined as the presence of ≥2 ACA, and a very CK (CK+) as ≥3 ACA. Eighty-nine patients (8%) had a CK, of whom 41 (4%) had CK+. The 5-year cumulative incidence of relapse (CIR) in patients with CK was 18%, and 12% in those with <2 ACA (p=.09). Among patients wi…
Frequent genomic imbalances suggest commonly altered tumour genes in human hepatocarcinogenesis
2001
Hepatocellular carcinoma (HCC) is one of the most frequent-occurring malignant tumours worldwide, but molecular changes of tumour DNA, with the exception of viral integrations and p53 mutations, are poorly understood. In order to search for common macro-imbalances of genomic tumour DNA, 21 HCCs and 3 HCC-cell lines were characterized by comparative genomic hybridization (CGH), subsequent database analyses and in selected cases by fluorescence in situ hybridization (FISH). Chromosomal subregions of 1q, 8q, 17q and 20q showed frequent gains of genomic material, while losses were most prevalent in subregions of 4q, 6q, 13q and 16q. Deleted regions encompass tumour suppressor genes, like RB-1 a…