Biomedical subjects

Tal Anahory

Publications and source records attributed to Tal Anahory.

8 recordsLinked to original sources

PubMed2006

The human cumulus--oocyte complex gene-expression profile.

BACKGROUND: The understanding of the mechanisms regulating human oocyte maturation is still rudimentary. We have identified transcripts differentially expressed between immature and mature oocytes and cumulus cells. METHODS: Using oligonucleotide microarrays, genome-wide gene expression was studied in pooled immature and mature oocytes or cumulus cells from patients who underwent IVF. RESULTS: In addition to known genes, such as DAZL, BMP15 or GDF9, oocytes up-regulated 1514 genes. We show that PTTG3 and AURKC are respectively the securin and the Aurora kinase preferentially expressed during oocyte meiosis. Strikingly, oocytes overexpressed previously unreported growth factors such as TNFSF13/APRIL, FGF9, FGF14 and IL4 and transcription factors including OTX2, SOX15 and SOX30. Conversely, cumulus cells, in addition to known genes such as LHCGR or BMPR2, overexpressed cell-to-cell signalling genes including TNFSF11/RANKL, numerous complement components, semaphorins (SEMA3A, SEMA6A and SEMA6D) and CD genes such as CD200. We also identified 52 genes progressively increasing during oocyte maturation, including CDC25A and SOCS7. CONCLUSION: The identification of genes that were up- and down-regulated during oocyte maturation greatly improves our understanding of oocyte biology and will provide new markers that signal viable and competent oocytes. Furthermore, genes found expressed in cumulus cells are potential markers of granulosa cell tumours.

Aurora Kinase C↗

PubMed2006

Obesity does not adversely affect results in patients who are undergoing in vitro fertilization and embryo transfer.

OBJECTIVE: To examine the outcome of in vitro fertilization according to the body mass index of infertile patients. STUDY DESIGN: Between September 2003 and May 2005, 573 patients underwent 789 in vitro fertilization cycles or ICSI because of male factor, tubal factor, and unexplained infertility were retrospectively included from our IVF database. The patients were classified in four groups: BMI<20 kg/m2 (264 cycles), 20< or = BMI<25 (394 cycles), 25< or = BMI < 30 (83 cycles), and BMI> or = 30 (48 cycles). All patients had a long protocol for IVF with a combination of the GnRH agonist and recombinant FSH. RESULTS: All parameters of ovarian response were comparable except the total required r-FSH dose. This dose was statistically higher in the group of BMI> or = 30 compared to the other groups (p = 0.0003). All parameters of IVF outcome were comparable, including the cancellation rate, the implantation rate, and pregnancy rates. CONCLUSION: Obese patients require a higher r-FSH dose to achieve follicular maturation than normal weight patients. Obesity does not affect negatively results of in vitro fertilization.

Adult↗

PubMed2006

Comparative protein expression profiling in human cumulus cells in relation to oocyte fertilization and ovarian stimulation protocol.

Comparative profiling was performed on proteins synthesized in human cumulus cells (CC) from individual oocytes recovered after two different ovarian stimulation protocols for classical IVF (cIVF). Using high-resolution two-dimensional protein electrophoresis after metabolic labelling with [35S]-methionine, protein expression was profiled in CC of metaphase II oocytes obtained after two different ovarian stimulation protocols (rFSH versus human menopausal gonadotrophin). Analysis was done on CC from two cIVF cycles in the same patient and then extended to CC from individual oocytes from two groups of patients. CC from single oocytes have robust levels of protein expression into 600-800 protein spots. Comparison of CC protein expression from oocytes obtained from the same patient but after two different stimulation protocols shows that the type of hormonal treatment influences CC protein expression. In contrast, CC from oocytes obtained under the same stimulation protocol but with different fertilization outcome show a high profile similarity with differences in only a few spots. Comparison of two groups of patients indicates that dissimilarities in protein pattern between patients become very high, even when comparing the same stimulation protocol and oocyte fertilization outcome. Thus protein expression profiling of human CC may provide a correlation between the synthesis of specific cumulus proteins and maturity and fecundity.

Female↗

PubMed2006

PRINS as an efficient tool for aneuploidy assessment in human oocytes and preimplantation embryos.

An ultrarapid three- and four-color primed in situ (PRINS) procedure has been developed for rapid chromosome identification and aneuploidy assessment on isolated cells. Based on the direct in situ mixing of fluorochromes (fluorescein isothiocyanate, tetramethylrhodamine isothiocyanate, Cascade Blue), this multicolor PRINS procedure is described on unfertilized human oocytes and isolated human blastomeres.

Aneuploidy↗

PubMed2005

The occurrence of aneuploidy in human: lessons from the cytogenetic studies of human oocytes.

During the last 4 decades, the cytogenetic investigation of human oocytes has never stopped to progress, according to the advents of new technologies. Both karyotyping and molecular cytogenetic studies have been reported to date, providing a large body of data on the incidence and the distribution of chromosomal abnormalities in human female gametes. However, these studies display a great variability in results, which may be essentially attributable to the limitations of these techniques when applied to human oocytes. The most relevant analysis have led to the estimate that 15-20% of human oocytes present chromosome abnormalities, and they have emphasized the implication of both whole chromosome nondisjunction and chromatid separation in the occurrence of aneuploidy in human oocytes. The effect of advanced maternal age on the incidence of aneuploidies in human oocytes has also been clearly evidenced by recent reports based on large sample of oocytes or polar bodies, whereas most of initial studies have failed to confirm any relationship between maternal age and aneuploidy in human oocytes.

Aneuploidy↗

PubMed2004

Fast multicolor primed in situ protocol for chromosome identification in isolated cells may be used for human oocytes and polar bodies.

OBJECTIVE: To present and evaluate the use of a new ultra-fast multicolor primed in situ (PRINS) procedure for karyotyping human oocytes and first polar bodies. DESIGN: In situ chromosomal identification on isolated cells, using combinations of specific primers for chromosomes 1, 7, 9, 16, and 18 and fluorescent nucleotides. SETTING: Sixteen unfertilized oocytes were obtained from women participating in an IVF program. PATIENT(S): Five patients undergoing an IVF-ET. INTERVENTION(S): In vitro unfertilized oocytes were fixed on slides, and sequential PRINS reactions were performed on each preparation. MAIN OUTCOME MEASURE(S): Ultrarapid in situ identification of three or four chromosomes on oocyte and polar body chromosome spreads. RESULT(S): On the basis of the direct in situ mixing of the colors of fluorochromes (FITC, TRITC, Cascade Blue) that were incorporated in sequential PRINS reactions, this method allows rapid and efficient labeling of three or four individual chromosomes. Each PRINS reaction consists of a unique 4- to 6-minute step for both in situ annealing and elongation. The procedure can be combined with fluorescence in situ hybridization (FISH) reactions. CONCLUSION(S): By simplifying the multicolor PRINS procedure, this new protocol should facilitate the use and adaptation of PRINS to chromosome screening. This approach could be used in parallel or in combination with FISH for efficient aneuploidy assessment on isolated cells.

Chromosome Mapping↗

PubMed2004

Fluorescence in situ hybridization analysis of human oocytes: advantages of a double-labeling procedure.

OBJECTIVE: To improve the fluorescence in situ hybridization (FISH) chromosomal analysis of human oocytes and first polar bodies. DESIGN: In situ chromosomal identification on isolated cells, with combinations of centromeric (or locus-specific) probes and whole-chromosome painting probes for chromosomes 9, 13, 16, 18, 21, and X. SETTING: Montpellier University Hospital. PATIENT(S): Women participating in an IVF program. INTERVENTION(S): Fifty-four in vitro unfertilized oocytes were fixed on slides, and simple or double FISH labeling procedures were performed on preparations. MAIN OUTCOME MEASURE(S): Simultaneous in situ visualization of specific domains and chromosome arms of each targeted chromosome. RESULT(S): Eight chromosomal abnormalities were identified, including two hyperhaploidies, three cases of extra single chromatid, and three cases of balanced separation of sister chromatids. Also, the double-labeling procedure allowed the avoidance of five interpretation errors, owing to additional artefactual signals. CONCLUSION(S): By ensuring precise identification of both chromosomes and single chromatids, the FISH double-labeling procedure limits the risk of erroneous interpretation and allows a more accurate cytogenetic analysis of human oocytes.

Chromosome Aberrations↗

PubMed2002

Identification of new proteins in follicular fluid of mature human follicles.

Proteins present in human follicular fluid (HFF) have been poorly characterized to date. The purpose of our study was to analyse the protein content and identify new proteins originating from fluid of mature human follicles. A total of six females from infertile couples referred for in vitro fertilization (IVF) were stimulated and 44 follicular fluid samples from mature follicles yielding an oocyte were collected 34-36 h after human chorionic gonadotropin administration. HFF samples were processed for high-resolution two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). Comparative analysis of the 2-D gels revealed up to 600 spots, of which four were selected because of variations in their expression level. Using direct sequencing procedures (Edman degradation) or matrix assisted laser desorption/ionization-mass spectrometry (MALDI-MS), these four spots were identified as three new proteins: thioredoxin peroxydase 1 (TDPX1), transthyretin (TTR) and retinol-binding protein (RBP). The proteins identified here may emerge as potential candidates for specific functions during folliculogenesis and may prove useful as biomedical markers for follicle and/or oocyte maturation.

Amino Acid Sequence↗