Napping and cognitive performance during night shifts : A systematic review and meta-analysis

Study Objectives To examine the benefits of napping during night shifts on cognitive performance. Methods Medline, Cochrane Library, Science direct, and Embase databases were searched up to July 1, 2019. Cognitive performance during night shifts, both before and following napping or under control conditions (no nap), in working-aged adults, were analyzed by time and by type of cognitive function (executive function, attention, instrumental function, and memory). Estimates were pooled using random-effects meta-analysis. Results A total of 18 articles (6 in real-work and 12 in laboratory) with a total of 494 participants were included. The mean nap duration was 41.6 ± 28.3 min, occurring between 12.00 am and 4.10 am, with a mean time set at 2.12 am. Cognitive performance did not differ at baseline between the groups (effect size 0.02, 95% CI −0.09 to 0.13). There was an overall improvement in performance following a nap compared to the control condition without a nap (0.25, 0.10 to 0.41). Positioning naps early in the night and activity (simulated work tasks) tended to improve cognitive performance (−0.57, −1.16 to 0.002, and 0.082, −0.04 to 0.33, respectively). The improvements were primarily seen 30 min after awakening. Only memory deteriorated immediately after awakening without an overall change in global cognitive performance. Conclusion Napping during night shifts seems to improve cognitive performance. Napping early in the night and activity may benefit cognitive performance over time. Considering lack of data in real work environments, further studies are warranted before preconizing napping during night shifts as a preventive strategy (safety, health, and economic outcomes)

In cryptozoospermia or severe oligozoospermia is sperm freezing useful?

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Is sperm FISH analysis still useful for Robertsonian translocations? Meiotic analysis for 23 patients and review of the literature

Résumé Contexte Le mode de ségrégation chromosomique le plus fréquemment observé chez les patients porteurs de translocation robertsonienne est. un mode équilibré. Les données semblent varier peu selon la translocation analysée. La relative constance des résultats dans le cas de ces translocations robertsoniennes rend elle inutile ces analyses chromosomiques pour ces patients? Patients et méthodes Nous avons analysé de façon rétrospective les données spermatiques et de ségrégation méiotique de 23 patients porteurs de translocation robertsonienne, de 2003 à 2017 et comparé les résultats observés à ceux décrits dans la littérature pour 187 patients. Résultats Le mode de ségrégation alterne est. prépondérant dans notre série de patients avec 73.45% ±8.05 de spermatozoïdes équilibrés (min 50.92%; max 89.99%). Ces résultats sont en accord avec les données de la littérature, toutes translocations confondues et selon le type de translocation (p > 0.05) sauf pour la translocation der(13;15) où ces taux sont significativement plus faibles (p < 0.05 vs der(13;14), der(14;21), (13;21) et der(15;22)). Nous observons également des taux de spermatozoïdes équilibrés significativement plus élevés chez les patients à spermogramme normal (p < 0.01). Conclusions Les différences observées dans les taux d’aneuploïdies entre les translocations der(13;15) et les autres translocations robertsoniennes et entre les porteurs de translocation à spermogramme normal ou altéré, et l’utilité de ces données dans le conseil génétique conduisent à poursuivre l’analyse systématique de la ségrégation méiotique pour les patients porteurs de translocations robertsoniennes et ceci particulièrement pour les translocations rares

FISH and Chimps: Insights into Frequency and Distribution of Sperm Aneuploidy in Chimpanzees (Pan troglodytes)

Numerical chromosomal aberrations in sperm are considered to be a major factor in infertility, early pregnancy loss and syndromes with developmental and cognitive disabilities in mammals, including primates. Despite numerous studies in human and farm animals, the incidence and importance of sperm aneuploidies in non-human primate remains mostly undetermined. Here we investigated the incidence and distribution of sperm aneuploidy in chimpanzees (Pan troglodytes), the species closest to human. We identify evolutionary conserved DNA sequences in human and chimpanzee and selected homologous sub-telomeric regions for all chromosomes to build custom probes and perform sperm-FISH analysis on more than 10,000 sperm nuclei per chromosome. Chimpanzee mean autosomal disomy rate was 0.057 ± 0.02%, gonosomes disomy rate was 0.198% and the total disomy rate was 1.497%. The proportion of X or Y gametes was respectively 49.94% and 50.06% for a ratio of 1.002 and diploidy rate was 0.053%. Our data provide for the first time an overview of aneuploidy in non-human primate sperm and shed new insights into the issues of aneuploidy origins and mechanisms

PROK1 Level in the Follicular Microenvironment: A New Noninvasive Predictive Biomarker of Embryo Implantation

International audienceProkineticin 1 (PROK1), also called endocrine gland-derived vascular endothelial growth factor, is a well-established regulator of endometrial receptivity and placental development. However, its clinical usefulness as a noninvasive predictive biomarker of embryo implantation is yet to be validated.PROK1 levels in FF and FCM could constitute new predictive noninvasive markers of successful embryo implantation in conventional in vitro fertilization-embryo transfer

Prokineticin 1 is a new biomarker of human oocyte competence: expression and hormonal regulation throughout late folliculogenesis

International audienceProkineticin 1 (PROK1) quantification in global follicular fluid (FF) has been recently reported as a predictive biomarker of in vitro fertilization (IVF) outcome. It is now necessary to evaluate its clinical usefulness in individual follicles.Sixty-nine infertile couples underwent in vitro fertilization (IVF)

Spermaurin, an La1-like peptide from the venom of the scorpion Scorpio maurus palmatus , improves sperm motility and fertilization in different mammalian species

International audienceSTUDY QUESTIONIs it possible to identify original compounds that are able to enhance sperm motility from the venom of the scorpion Scorpio maurus palmatus?SUMMARY ANSWERWe identified a potent disulfide-rich peptide (DRP) of 73 amino acids that significantly improved the motility of fresh and frozen-thawed sperm in different mammalian species, including human, and improved fertilization outcome in mouse IVF experiments.WHAT IS KNOWN ALREADYAny disturbance of sperm motility has a strong impact on fertilization and can lead to subfertility or infertility. Significant efforts have, therefore,  been made to identify pharmacological drugs that might improve sperm motility. Such compounds are particularly useful in azoospermia to improve testicular sperm extraction and in the domain of cryopreservation because the motility of frozen-thawed sperm is reduced.STUDY DESIGN, SIZE, DURATIONThis was a basic science/medical research study aimed at identifying original compounds from a library of venoms able to enhance mammalian sperm motility, including human. We first identified in the venom of a scorpion S. m. palmatus a fraction able to potently activate sperm motility. We next purified and characterized the compound by liquid chromatography, mass spectrometry and peptide synthesis. Finally, the potency and toxicity of both purified and synthetic versions of the identified compound on sperm motility were assessed using different in vitro tests in different mammalian species.PARTICIPANTS/MATERIALS, SETTING, METHODS For human sperm, biological samples were collected from normozoospermic donors and subfertile patients attending a reproduction department for diagnostic semen analysis. Testicular sperm was collected from cynomolgus monkeys (Macaca fascicularis) euthanized for the needs of specific authorized research projects. The peptide was also tested on bovine and mouse epidydimal sperm. We measured different sperm motility parameters with a computer-assisted sperm analysis system in the presence or absence of the peptide.MAIN RESULTS AND THE ROLE OF CHANCESize exclusion chromatography enabled us to isolate a fraction of the venom of S. m. palmatus able to increase sperm motility. By liquid chromatography and mass spectrometry, a peptide comprising 73 amino acids with 4 disulfide bridges was identified as responsible for the biological activity and called ‘spermaurin’. The identity of spermaurin was confirmed by chemical synthesis. We showed that the peptide increased the motility of fresh and frozen-thawed human sperm. We observed that the potency of the peptide was higher on fresh ejaculated spermatozoa with a low motility, achieving a 100% increase of curvilinear velocity in poorly performing sperm. We also demonstrated that peptide is effective on bovine and mouse fresh epididymal, bovine frozen-thawed ejaculated and fresh non-human primate testicular sperm. Finally, in mouse IVF, the production of 2-cell embryos was increased by 24% when sperm were treated with the peptide.LIMITATIONS, REASONS FOR CAUTIONThis work is an in vitro evaluation of the ability of spermaurin to improve sperm motility parameters. Another limitation of this study is the small number of human sperm samples tested with the natural (n = 36) and synthetic (n = 12) peptides. Moreover, the effect of the peptide on IVF outcome was only tested in mouse and further tests with human and bovine gametes are required to confirm and extend this result in other mammalian species.WIDER IMPLICATIONS OF THE FINDINGSThis work confirms our initial study showing that venoms represent an interesting source of molecules that are able to modify sperm physiology. Moreover, this work presents the first demonstrated biological action of a venom peptide from the scorpion S. m. palmatus with sequence similarities to La1 peptide from Liocheles australasiae (Wood scorpion), a widespread family of DRPs.STUDY FUNDING/COMPETING INTEREST(S)This work is part of the project ‘LAB COM-14 LAB7 0004 01-LIPAV’, funded by the program LabCom 2014 from t e French Research Agency (ANR). Dr Arnoult reports grants from IMV Technologies during the conduct of the study. In addition, Drs Arnoult, Martinez, Ray and Schmitt have a patent EP16305642.7 pending containing some of the information presented in this manuscript

Genetic analyses of a large cohort of infertile patients with globozoospermia, DPY19L2 still the main actor, GGN confirmed as a guest player

International audienceGlobozoospermia is a rare phenotype of primary male infertility inducing the production of round-headed spermatozoa without acrosome. Anomalies of DPY19L2 account for 50-70% of all cases and the entire deletion of the gene is by far the most frequent defect identified. Here, we present a large cohort of 69 patients with 20-100% of globozoospermia. Genetic analyses including multiplex ligation-dependent probe amplification, Sanger sequencing and whole-exome sequencing identified 25 subjects with a homozygous DPY19L2 deletion (36%) and 14 carrying other DPY19L2 defects (20%). Overall, 11 deleterious single-nucleotide variants were identified including eight novel and three already published mutations. Patients with a higher rate of round-headed spermatozoa were more often diagnosed and had a higher proportion of loss of function anomalies, highlighting a good genotype phenotype correlation. No gene defects were identified in patients carrying 50% of globozoospermia. In addition, results from whole-exome sequencing were scrutinized for 23 patients with a DPY19L2 negative diagnosis, searching for deleterious variants in the nine other genes described to be associated with globozoospermia in human (C2CD6, C7orf61, CCDC62, CCIN, DNAH17, GGN, PICK1, SPATA16, and ZPBP1). Only one homozygous novel truncating variant was identified in the GGN gene in one patient, confirming the association of GGN with globozoospermia. In view of these results, we propose a novel diagnostic strategy focusing on patients with at least 50% of globozoospermia and based on a classical qualitative PCR to detect DPY19L2 homozygous deletions. In the absence of the latter, we recommend to perform whole-exome sequencing to search for defects in DPY19L2 as well as in the other previously described candidate genes