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Biomedical subjects

Moncef Benkhalifa

Publications and source records attributed to Moncef Benkhalifa.

7 recordsLinked to original sources

IVM rescue: Effect of growth hormone supplementation combined to autologous cumulus co-culture on GV oocyte maturation and competency.

OBJECTIVE: IVM rescue is based on the in vitro maturation of mainly Germinal Vesicle (GV) oocytes collected from stimulated cycles. The objective was to investigate the effects of growth hormone (GH) and autologous cumulus cells co culture (CC) on oocyte meiosis resumption and maturation after 32 h post cumulus denudation, in order to obtain additional embryos for the couple as a rescue system to increase the changes of cumulative pregnancy. MATERIAL AND METHODS: Our study concerned 300 patients who underwent ICSI cycles, during which a total of 1940 cumulus-complex-oocytes were retrieved, giving 1260 metaphase II stage (MII), 200 at the metaphase I stage, and 480 at the Germinal Vesicle (GV) stage. Mature oocytes were microinjected on the same day of retrieval. Immature GV oocytes were divided into four groups, with the first undergoing in vitro maturation (IVM) without cumulus cells (group 1) and the second undergoing IVM with CC (group 2), the third undergoing IVM without CC and with GH (group 3), the fourth undergoing IVM with CC and with GH (group 4). After 32 h of IVM, the matured oocytes, underwent microinjection, followed by embryonic development monitoring. RESULTS: When comparing the IVM outcomes, we observed a significant increase in oocyte maturation, fertilization rates and the percentage of 8-cell embryos on day 3 across the different study groups (p < 0.001) (Figs. 2-5). Furthermore, all study groups (1-4) exhibited notably blastulation rates, with group 3 demonstrating the most promising clinical outcomes. A preliminary pregnancy rate of approximately 20% was recorded in group 3, suggesting a potential improvement in the developmental competence of oocytes matured under specific conditions. CONCLUSION: The IVM rescue of germinal vesicle oocyte could serve as an additional strategy to increase the chance getting extra embryos to patients. Autologous cumulus cells co-culture combined to GH supplementation to IVM media, appear to play a crucial role to enhance successful meiosis resumption, oocyte maturation and competency to support embryos development when the injected spermatozoa is not carrier of severe genome and epigenomic decays.

Humans↗

Retrospective diagnosis of Pallister-Killian syndrome by CGH array.

OBJECTIVE AND METHODS: We report a girl presenting with a polymalformation syndrome. Despite a normal karyotype on peripheral lymphocytes and the unavailability of cultured fibroblasts, a tetrasomy 12p was identified on pulmonary DNA extracted from a postmortem biopsy, by use of comparative genomic hybridization (CGH) and confirmed by CGH array. The clinical picture of our patient was consistent, but not specific of the diagnosis of Pallister-Killian syndrome. She presented with the association of antenatal polyhydramnios, craniofacial dysmorphic features, skeletal abnormalities, and a congenital cardiopathy. CONCLUSION: We discuss the usefulness of CGH and CGH array in prenatal and constitutional cytogenetics.

Abnormalities, Multiple↗

De novo monosomy 9p24.3-pter and trisomy 17q24.3-qter characterised by microarray comparative genomic hybridisation in a fetus with an increased nuchal translucency.

OBJECTIVES: Increased nuchal translucency (NT) during the first trimester of pregnancy is a useful marker to detect chromosomal abnormalities. Here, we report a prenatal case with molecular cytogenetic characterisation of an abnormal derivative chromosome 9 identified through NT. METHODS: Amniocentesis was performed because of an increased NT (4.4 mm) and showed an abnormal de novo 46,XX,add(9)(p24.3) karyotype. To characterise the origin of the small additional material on 9p, we performed a microarray comparative genomic hybridisation (microarray CGH) using a genomic DNA array providing an average of 1 Mb resolution. RESULTS: Microarray CGH showed a deletion of distal 9p and a trisomy of distal 17q. These results were confirmed by FISH analyses. Microarray CGH provided accurate information on the breakpoint regions and the size of both distal 9p deletion and distal 17q trisomy. The fetus was therefore a carrier of a de novo derivative chromosome 9 arising from a t(9;17)(p24.3;q24.3) translocation and generating a monosomy 9p24.3-pter and a trisomy 17q24.3-qter. CONCLUSION: This case illustrates that microarray CGH is a rapid, powerful and sensitive technology to identify small de novo unbalanced chromosomal abnormalities and can be applied in prenatal diagnosis.

Abnormalities, Multiple↗

Multiple displacement amplification on single cell and possible PGD applications.

Multiple displacement amplification (MDA) is a technique used in the amplification of very low amounts of DNA and reported to yield large quantities of high-quality DNA. We used MDA to amplify the whole genome directly from a single cell. The most common techniques used in PGD are PCR and fluorescent in-situ hybridization (FISH). There are many limitations to these techniques including, the number of chromosomes diagnosed for FISH or the quality of DNA issued from a single cell PCR. This report shows, for the first time, use of MDA for single cell whole genome amplification. A total of 16 short tandem repeats (STRs) were amplified successfully with a similar pattern to the genomic DNA. Furthermore, allelic drop out (ADO) derived from MDA was assessed in 40 single cells by analysing (i) heterozygosity for a known beta globin mutation (IVSI-5 C-G) and by studying (ii) the heterozygous loci present in the STRs. ADO turned out to be 10.25% for the beta globin gene sequencing and 5% for the fluorescent PCR analysis of STRs. Moreover, the amplification accuracy of MDA permitted the detection of trisomy 21 on a single cell using comparative genome hybridization-array. Altogether, these data suggest that MDA can be used for single cell molecular karyotyping and the diagnosis of any single gene disorder in PGD.

Alleles↗

Cytogenetic abnormalities and the failure of development after round spermatid injections.

OBJECTIVE: To assess cytologic and cytogenetic abnormalities following round spermatid injection. DESIGN: Prospective analysis. SETTING: In vitro fertilization centers. PATIENT(S): Fourteen couples accepted to a round spermatid injection (ROSI) and preimplantation genetic diagnosis (PGD) program after appropriate counseling. INTERVENTION(S): ROSI, PGD, with fluorescence in situ hybridization for chromosome enumeration. MAIN OUTCOME MEASURE(S): Cytologic and cytogenetic abnormalities in oocytes, zygotes, and blastomeres. RESULT(S): The fertilization rate following ROSI was 36%. Only 11 of 143 (7.7%) oocytes developed to have several blastomeres. Cytologic and cytogenetic abnormalities accounted for the vast majority of blockage at oocyte, zygote, and early mitotic division stages. Four biopsied embryos were normal. These and seven others were implanted, but no pregnancy was achieved. CONCLUSION(S): A PGD diagnosis for common aneuploidies and blastocyst stage transfer is feasible for ROSI cases. Failure with ROSI is cause primarily by chromosome abnormalities, so use of ROSI in assisted reproductive technologies should be limited.

Chromosome Aberrations↗

Could sperm aneuploidy rate determination be used as a predictive test before intracytoplasmic sperm injection?

Chromosome abnormalities in embryos are a major cause of implantation and development failures. Some couples with normal karyotypes have repeated implantation failures after intracytoplasmic sperm injection (ICSI). In order to value patients at risk for genetic ICSI failures and the validity of sperm aneuploidy analysis, we have studied cytogenetic abnormalities in sperm from ICSI patients. Twenty-nine patients with normal karyotypes were included. Ten patients had at least 4 ICSI treatments without pregnancy (group A). Nine patients had a pregnancy after 1 to 3 ICSI treatments (group B). Ten fertile men with normal semen parameters were studied as controls (group C). Fluorescent in situ hybridization (FISH) was used for sperm nucleus cytogenetic analysis using chromosomes 8, 9, 13, 18, 21, X, and Y specific probes. Aneuploidy for each chromosome and diploidy rates were significantly higher in group A than in group B and in group B than in group C (P < .05). Considering each patient in groups A and B, aneuploidy rate for each chromosome was too variable to be considered as a significant test. We proposed analysis of the total sperm aneuploidy. Chromosomal sperm nuclei profile could be used as a predictive biological test before ICSI in order to improve genetic counseling for oligoasthenoteratozoospermia patients.

Aneuploidy↗