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Pierre Jouannet

Publications and source records attributed to Pierre Jouannet.

8 recordsLinked to original sources
PubMed2004

How can the genetic risks of embryo donation be minimized? Proposed guidelines of the French Federation of CECOS (Centre d'Etude et de Conservation des Oeufs et du Sperme).

Embryo donation is now an acceptable practice which offers new possibilities to many infertile couples wishing to procreate. In France, embryo donation, like gamete donation, is controlled by law, but its application has been poorly developed because too many questions remained unsolved and because of the lack of practical guidelines. Here we report the results of the debate which took place within the Genetics Commission of the French Federation of CECOS and the proposed recommendations which followed, emphasizing the genetic background to be considered for embryo donation.

France↗
PubMed2004

Mutation analysis of the BOULE gene in men with non-obstructive azoospermia: identification of a novel polymorphic variant in the black population.

The BOULE gene is a member of the 'deleted in azoospermia'DAZ family. As in flies and worms, disruption of the BOULE homologues leads to meiotic defects during the first meiotic division, we screened the coding region of the BOULE gene from 40 infertile men with non-obstructive azoospermia or severe oligoasthenoteratozoospermia by denaturing high-pressure liquid chromatography and direct sequencing in order to make progress in elucidating the aetiology of male infertility. Two infertile patients were heterozygous for a novel G to C transversion in exon 2 resulting in a Q2E amino acid substitution. As these two infertile men were from African origin, screening of fertile African subjects identified this novel variant in two fertile male subjects suggesting that this novel Q2E substitution had non-pathologic role. Taking into account the size of our sample, we conclude that BOULE coding sequence mutations are not an important factor in the aetiology of azoospermia.

Amino Acid Sequence↗
PubMed2003

In vitro follicular growth affects oocyte imprinting establishment in mice.

In vitro folliculogenesis of cryopreserved ovarian tissue could be an effective method for insuring fertility for patients who receive gonadotoxic treatment. Although several culture systems have been described for growing female gametes in vitro, the production of competent oocytes for further development remains a considerable challenge. The purpose of our study was to determine whether maternal primary imprinting progresses normally during mouse oocyte growth in vitro. We analysed the DNA methylation status of differentially methylated regions of the imprinted genes H19, Mest/Peg1 and Igf2R using fully grown germinal vesicle-stage oocytes (fg oocytes) produced by in vitro folliculogenesis from early preantral follicles. When compared to fg oocytes removal from control females, we observed after in vitro development, a loss of methylation at the Igf2R locus in six out of seven independent experiments and Mest/Peg1 locus (one out of seven), and a gain of methylation at the H19 locus (one out of seven). These results provide insight into the dysregulation of the process of primary imprinting during oocyte growth in vitro and highlight the need for effective new biomarkers to identify complete nuclear reprogramming competence after in vitro folliculogenesis.

Animals↗
PubMed2003

Deficit in cytochrome c oxidase activity induced in rat sperm mitochondria by in vivo exposure to zidovudine.

A decreased sperm motility has been reported in men treated with nucleoside analog reverse transcriptase inhibitors (NRTI). Sperm motility is correlated with enzymatic activities of the sperm mitochondrial respiratory chain (MRC), which may be impaired by NRTI. We compared sperm and skeletal muscle MRC and citrate synthase (CS) activities, sperm adenosine triphosphate (ATP) content and sperm motility between rats exposed to zidovudine (AZT) for 10 weeks and controls. Decreased levels of CS-normalized cytochrome c oxidase (COX, the MRC complex IV) activity were observed in the spermatozoa from AZT-treated rats, with no significant decrease in ATP content or motility. In muscle absolute COX activity increased after exposure to AZT but CS-normalized COX activity remained unchanged. These results suggest that exposure to NRTI can induce MRC dysfunction earlier in spermatozoa than in skeletal muscle.

Adenosine Triphosphate↗
PubMed2002

Assisted reproduction in HIV-1-serodifferent couples: the need for viral validation of processed semen.

BACKGROUND: Many HIV-infected men and women have a strong desire for a child. Assisted reproductive technologies (ART) are an option for HIV-serodifferent couples to reduce the risk of HIV transmission from an infected man to the woman. Potential HIV contamination of selected spermatozoa after semen processing is an important issue in this context. METHODS: HIV in processed semen obtained in our laboratory since 1995 were analysed. HIV RNA and DNA detection was performed in the selected spermatozoa of 125 men. HIV RNA was analysed in blood and semen plasma as well as HIV DNA in non-sperm cells. RESULTS: HIV RNA and DNA were detected in the selected spermatozoa of eight and two men (6.4% and 1.6%), respectively. HIV RNA was detected with a median load of 5 copies/10(6) spermatozoa. Six of the eight men were untreated, one was taking nucleoside analogue therapy and one was on highly active antiretroviral treatment (HAART). HIV RNA detection was more likely to be positive in selected spermatozoa of men with high seminal plasma viral load. HIV RNA was detected in 26% and 11% of selected spermatozoa fractions when the seminal plasma load was > 10,000 copies/ml and 20-10,000 copies/ml, respectively, but in none when the seminal plasma tested negative. CONCLUSION: Selected spermatozoa may be positive for HIV RNA detection even in treated patients. Viral validation of processed semen is necessary in ART programmes for serodifferent couples, particularly in men with only partially or poorly controlled HIV infection.

Anti-HIV Agents↗
PubMed2002

The human "prion-like" protein Doppel is expressed in both Sertoli cells and spermatozoa.

The prion-like Doppel protein (Dpl) has many biochemical and structural properties in common with the cellular prion protein (PrP(c)), and the physiological role of neither protein is known. Experimental data suggest either direct or indirect interaction between the two proteins. In this study, we investigated the expression pattern and biochemical characteristics of Dpl in human tissues and in Chinese hamster ovary cells transfected with wild-type or variant human Dpl gene constructs. Human Dpl appears to be a glycosylphosphatidylinositol-anchored glycoprotein with N- and O-linked sugars. It was found on Sertoli cells in the testis, on the flagella of epididymal and mature spermatozoa, and in seminal plasma. Dpl coexists only with N-terminally truncated isoforms of PrP(c) on mature spermatozoa. The localization of human Dpl on both Sertoli cells (somatic cells) and spermatozoa (germinal cells) strongly suggests that this protein may play a major role in human male fertility. Finally, our data indicate that spermatozoa are thus an interesting model for studies of the potential interaction between Dpl and PrP(c).

Animals↗
PubMed2002

Human ovarian tissue cryopreservation: indications and feasibility.

BACKGROUND: The cryopreservation of ovarian tissue may enable women exposed to gonadotoxic treatments to have children at a later date. METHODS: Between April 1998 and October 2000, we evaluated the feasibility of long-term ovarian tissue cryopreservation in 51 women who were all at risk of becoming sterile following treatment. RESULTS: Ovarian tissue was not cryopreserved in 20 cases because of the woman's age or premature ovarian failure. In 31 patients, ovarian tissue was frozen by a slow cooling technique using DMSO and sucrose as cryoprotectants. The patients were aged 2.7-34 years and 16 of them were <18 years old. Cryopreservation could be performed in all cases. Ovarian cortex histology was performed for all patients to evaluate the concentration of follicles. The mean number of primordial and primary follicles per mm(2) was 20.36 +/- 19.03 before 10 years of age, 4.13 +/- 2.9 between 10 and 15 years of age and 1.63 +/- 3.35 after 15 years of age. An average mean number of 26 +/- 8.2 ovarian fragments (range 13-50) were cryopreserved per patient for future autografts or for in-vitro growth of follicles. CONCLUSION: Cryopreservation of ovarian tissue may be systematically proposed to young women and girls at risk of becoming sterile as a result of gonadotoxic treatment.

Adolescent↗