Search results for "Ploidy"
showing 10 items of 299 documents
False positive rate of an arrayCGH platform for single-cell preimplantation genetic screening and subsequent clinical application on day-3
2013
In this work, false positive rate of an arrayCGH platform for its use in day-3 single-blastomere analysis was calculated. For this purpose, 38 embryos diagnosed as abnormal on day-3 by FISH were re-biopsied on day-4. Single-cell day-4 arrayCGH diagnosis was then performed. A successful amplification was obtained in 97.4 % (37/38) of the day-4 cells analysed by arrayCGH. Day-3 FISH and day-4 arrayCGH diagnosis were concordant in 35/37 cases. The two discordant embryos were spread and all the cells from each embryo were re-analysed by FISH on day 5. The same error rate (2.7 %) for day-3 FISH and day-4 arrayCGH was obtained when comparing day-5 FISH re-analysis. After this pre-clinical phase, …
Retinoblastoma epidemiology: Does the evidence matter?
2007
It has been proposed that retinoblastoma is 'caused' by two sequential mutations affecting the RB1 gene, but this is a rather outdated view of cancer aetiology that does not take into account a large amount of new acquisitions such as chromosomal and epigenetic alterations. Retinoblastoma remains probably the only cancer in which the rather simplistic 'two hit' mutational model is still considered of value, although cancer is known to be associated with genomic and microsatellite instability, defects of the DNA mismatch repair system, alterations of DNA methylation and hystone acethylation/deacethylation, and aneuploidy. Moreover, as it is shown herein, the predictions made by the 'two hit'…
First-trimester screening for trisomy-21 using a simplified method to assess the presence or absence of the fetal nasal bone.
2005
Objective To determine the benefit of including nasal bone assessment in addition to standard first-trimester markers (nuchal translucency, free beta human chorionic gonadotropin and pregnancy-associated plasma protein A) as a screening test for Down syndrome, using a strict criterion for classification of nasal bone absence. Study design Nasal bone assessment was conducted in 2411 patients with crown-rump length between 45 and 84 mm, including 15 patients with Down syndrome. A patient was considered to have an absent nasal bone only if there was no evidence of present nasal bone. Unlike other studies, nasal bone was classified as present when there was evidence of a thin echogenic line und…
Forty-two supernumerary marker chromosomes (SMCs) in 43,273 prenatal samples: chromosomal distribution, clinical findings, and UPD studies.
2005
Fluorescence in situ hybridization (FISH) analyses were performed on supernumerary marker chromosomes (SMCs) detected in 43 273 prenatal diagnoses over a period of 11 years, 1993–2003. A total of 42 pregnancies with SMC were identified, indicating a prevalence of one in 1032. A total of 15 SMCs were endowed with detectable euchromatin (prevalence, 1/2884), including six SMCs containing the cat eye critical region (CECR) on chromosome 22q11.21 (1/7212). De novo SMCs were found in 29 pregnancies (1/1492), including 14 euchromatic SMCs (48.2%). Follow-up studies were available for 24 cases. Nine pregnancies (37.5%) were terminated; two children (8.3%) were born with Pallister–Killian syndrome …
Diagnostic genetic screening for assisted reproductive technologies patients with macrozoospermia
2017
International audience; Macrozoospermia is characterized by a high proportion of abnormal spermatozoa with enlarged heads. So far, it has been associated with mutations only in the Aurora Kinase C gene (AURKC) in some cases. Although many publications have reported failure to conceive in couples with macrozoospermia, a few others have described successful pregnancies, thus raising questions as to whether ICSI and AURKC genetic screening should be recommended in all patients with macrozoospermia. First, we report on two monozygotic twins presenting macrozoospermia for whom the genetic status was explored (Aurora Kinase C sequencing) and whole semen and gradient-selected spermatozoa were anal…
Evaluation of DNA ploidy and degree of DNA abnormality in benign and malignant melanocytic lesions of the skin using video imaging.
2000
BACKGROUND Making a morphologic distinction between benign and malignant melanocytic tumors of the skin is frequently difficult, especially because “gray zones” between these lesions often exist. DNA image cytometry as an adjuvant method for the diagnosis and prognostic prediction of premalignant lesions and malignant tumors of many other organs is already well established. The aim of this study was to determine whether DNA image cytometry is helpful in distinguishing benign from malignant melanocytic lesions and whether cytometry would give valid information with which to predict the prognoses associated with malignant melanomas. METHODS DNA image cytometry was performed on 127 benign and …
Cytogenetic findings in secondary acute nonlymphocytic leukemia
1992
Abstract We here report the results of cytogenetic studies carried out in eight patients with acute nonlymphocytic leukemia developed after primary neoplasias. In seven of the reported cases, clonal chromosome aberrations were found, some being specific of de novo acute nonlymphocytic leukemia (ANLL). Numerical abnormalities were detected, such as the total monosomy of chromosomes 5, 7, 21, trisomy of chromosomes 8, 11, 15, and duplication of chromosome Y. Structural changes were also observed: a del(12)(p12), a del(16)(q22), the translocations t(3;5)(p21;q35),t(3;7)(p21;q35), and t(12;14)(p12;q32) and other changes involving chromosome 8. The finding of a hypertetraploid karyotype with com…
Familial ring (18) mosaicism in a 23-year-old young adult with 46,XY,r(18) (::p11→q21::)/46,XY karyotype, intellectual disability, motor retardation …
2010
We report on a 23-year-old man with craniofacial findings of the holoprosencephaly spectrum disorder (microcephaly, hypotelorism, depressed nasal bridge, single median maxillary central incisor), fusion of C2-C3 vertebrae, intellectual disability, and severe sleep apnea. Chromosome analysis of blood lymphocytes showed 75% ring (18) cells and 25% normal cells, karyotype mos 46,XY,r(18)(::p11→q21::)[75]/46,XY[25]. His mother was phenotypically normal except for a double ureter and bifid renal pelvis as in his son. She had a supernumerary ring (18) in 10% of blood lymphocytes, karyotype mos 47,XX,+r(18)(::p11→q21::)[10]/46,XX[90]. Familial ring (18) is a rare cytogenetic abnormality. This is t…
FISH screening of aneuploidies in preimplantation embryos to improve IVF outcome
2005
Preimplantation genetic diagnosis (PGD) has transformed the approach to the infertility patient in the IVF setting. Although the principal applications of PGD have been to prevent the transmission of sex-linked diseases, in time and with growing knowledge of the chromosomal abnormalities observed in preimplantation embryos, its applications have widened. Nowadays, apart from its implications in the prevention of transmission of chromosomal and genetic abnormalities, PGD is being used with increased frequency to improve the IVF outcome in patients with advanced maternal age (or =38 years of age), recurrent miscarriage (or =2 miscarriages), recurrent IVF failure (or =3 failed IVF attempts) an…
Proliferative Activity and Cytometric Characteristics in Polyps of the Nasal Cavity and Paranasal Sinuses
2000
Although several investigations have revealed the influence of cytokines, allergy, and environmental factors in polyp development, the etiology of nasal polyps is still unknown. To estimate the biology of this common disease the operative specimens of 50 patients who underwent surgery for polyps of the nasal cavity and the paranasal sinuses were examined; of these, 10 patients had recurrent disease and 23 patients had an allergy. The investigations included routine histology and quantitative DNA measurements, along with immunohistochemical identification of proliferation markers (i.e., MIB-1; proliferating cell nuclear antigen, PCNA). Histologically, most polyps revealed an infiltration wi…