Search results for "Karyotype"
showing 10 items of 150 documents
Response to lenalidomide in myelodysplastic syndromes with del(5q): influence of cytogenetics and mutations.
2012
Summary Lenalidomide is an effective drug in low-risk myelodysplastic syndromes (MDS) with isolated del(5q), although not all patients respond. Studies have suggested a role for TP53 mutations and karyotype complexity in disease progression and outcome. In order to assess the impact of complex karyotypes on treatment response and disease progression in 52 lenalidomide-treated patients with del(5q) MDS, conventional G-banding cytogenetics (CC), single nucleotide polymorphism array (SNP-A), and genomic sequencing methods were used. SNP-A analysis (with control sample, lymphocytes CD3+, in 30 cases) revealed 5q losses in all cases. Other recurrent abnormalities were infrequent and were not ass…
Incidence and Prognostic Value of FLT-3 and NPM1 Genes Abnormalities in Acute Myeloid Leukemia in the Côte D’or Population, France
2008
Abstract Context: In acute myeloid leukemia (AML), the recently described FLT-3 and NPM1 genes abnormalities were found to have a prognostic value in AML with normal karyotype and a specific therapeutic strategy was proposed according to these abnormalities. We look for the incidence and prognostic value of these abnormalities in cases diagnosed on a well defined population. Material and Methods: AML diagnosed according to WHO classification between 01/01/2001 and 31/12/2006 in the population of the Côte d’Or department, were included. Karyotype analyses were performed in 81% of the cases. The FLT3 D835 mutation, the FLT3 internal duplication (ITD) and the NPM1 mutation were systematically…
Antioxidant therapy counteracts the disturbing effects of diamide and maternal ageing on meiotic division and chromosomal segregation in mouse oocytes
1998
This study aims (i) to ascertain whether oxidative-stress-induced disturbances in chromosomal distribution in the metaphase-II spindle of mouse oocytes can be counteracted by supplementing culture medium with antioxidants; and (ii) to determine whether supplemental intake of antioxidants neutralizes the disturbing effects of maternal ageing on segregation of chromosomes during the first meiotic division and distribution of chromosomes in the metaphase-II spindle. (i): Germinal vesicle oocytes from unstimulated 10-12 week old mice were matured in vitro in the presence or absence of diamide and/or dithiothreitol. Metaphase-II oocytes were fixed and stained with 4',6-diamidino-2-phenylindole (…
Phylogenomics of species from four genera of New World monkeys by flow sorting and reciprocal chromosome painting
2007
Abstract Background The taxonomic and phylogenetic relationships of New World monkeys (Platyrrhini) are difficult to distinguish on the basis of morphology and because diagnostic fossils are rare. Recently, molecular data have led to a radical revision of the traditional taxonomy and phylogeny of these primates. Here we examine new hypotheses of platyrrhine evolutionary relationships by reciprocal chromosome painting after chromosome flow sorting of species belonging to four genera of platyrrhines included in the Cebidae family: Callithrix argentata (silvered-marmoset), Cebuella pygmaea (pygmy marmoset), Callimico goeldii (Goeldi's marmoset) and Saimiri sciureus (squirrel monkey). This is t…
Endometrial stromal sarcomas: immunohistochemical, electron microscopical and cytogenetic findings in two cases.
1999
Uterine sarcomas are approximately 3% of all malignant uterine corpus tumours. Of these, the tumours that originate solely in the stromal elements of the uterine wall are infrequent and have not been well characterized cytogenetically. We report two cases of endometrial stromal sarcomas (ESS), one low grade and one high grade, diagnosed by conventional histology, immunocytochemistry, electron microscopy and cytogenetics. Morphologically clear-cut differential structures were seen at optical, immunohistochemical, and electron microscopic levels, permitting a clear differential diagnosis. The low-grade ESS expressed hormonal receptors and vimentin, whereas the high-grade ESS showed no hormone…
Haploinsufficiency of 16.4 Mb from chromosome 22pter-q11.21 in a girl with unilateral conductive hearing loss.
2009
We present the postnatal diagnosis of a de novo der(18)t(18;22)(p11.32;q11.21)pat, resulting in an unbalanced 45,XX,der (18)t(18;22) karyotype in a girl with conductive hearing loss on the left and ptosis of the right upper eye-lid. Unilateral ptosis was also observed in the patient’s 2 years and 8 months younger sister, who grows noticeably faster and appears to be a much quicker learner. After speech therapy the patient was eventually placed in normal school. The haploinsufficient 16.4-Mb region on chromosome 22pter→q11.21 contains 10 genes as well as many predicted genes, pseudogenes, and retrotransposed sequences with unknown functions. This observation may prove useful for prenatal dia…
The Phylogenetic position of Daubentonia madagascariensis (Gmelin, 1788; primates, Strepsirhini) as revealed by chromosomal analysis
2012
One of the major topics in primate evolution is the phylogenetic position of the bizarre Daubentonia madagascariensis (DMA, aye-aye). The principal points that have been discussed for many decades are whether the aye-aye is: (i) the sister group of primates; (ii) the sister group of strepsirhines; or (iii) the sister group of lemurs. Very little is known about Daubentonia evolution, particularly on the chromosomal background. The present report focuses on the chromosomal history of this species. We used available chromosome painting data as the main source to identify conserved chromosomes, chromosomal segments and syntenic associations that have characterized the aye-aye karyotype. The dat…
Cytogenetic analyses of culture failures by comparative genomic hybridisation (CGH)–Re-evaluation of chromosome aberration rates in early spontaneous…
2001
Comparative genomic hybridisation (CGH) represents an alternative molecular-cytogenetic technique capable of detecting chromosomal imbalances by reverse fluorescence in situ hybridisation. As the technique uses genomic DNA for assessment it does not rely on metaphase chromosomes in the test material and thus circumvents technical problems associated with tissue culturing. In the present study, we applied CGH to identify chromosome anomalies in 60 spontaneous abortions of the first trimester, that had failed to grow in culture. In 57 out of 60 cases CGH analyses were successful. The overall aneuploidy rate detected was 72%. Trisomy was the predominant chromosome anomaly accounting for 68.0% …
NOR regions of polychaete worms of the genus Ophryotrocha studied by chromosome banding techniques and FISH.
2000
This article reports the results of cytogenetic analyses carried out on 10 species of polychaete worms belonging to the genus Ophryotrocha (Dorvilleidae). Nucleolar organizer regions (NORs) were characterized by Ag staining, C-banding, CMA3 staining, and ribosomal fluorescent in situ hybridization (rDNA FISH). Extensive intraspecific variation in NOR number and distribution were observed in O. costlowi, O. sp. macrovifera, O. notoglandulata, O.l. labronica, O. l. pacifica (2n = 6), O. p. puerilis, O. diadema (2n = 8), O. hartmanni, O. gracilis (2n = 10). In O. sp. robusta (2n = 10), Ag-NORs were always located on a single chromosome pair. CMA3 staining suggests a possible trend toward a GC-…
Gene polymorphisms and HLA-G expression in spontaneous abortions
2015
Abstract Introduction HLA-G and HLA-E are claimed to play a role in establishing maternal–fetal immune tolerance and in maintaining pregnancy. The presence of polymorphism in the HLA-G gene could cause a deficient or excessive expression of the HLA-G and HLA-E molecules. These anomalies could eventually cause pregnancy losses. Materials and methods Clinical study. A total of 90 patients were included in this study. These patients suffered spontaneous abortions between weeks 6 and 11 of pregnancy. We have analysed the most important polymorphisms of the HLA-G gene through different genetic studies and HLA-G and HLA-E expression through immunostaining in human cytotrophoblast cells from first…