Place de l’analyse du mouvement dans un bilan de fertilité: Valeurs prédictives des différents paramètres mesurés

Routine evaluation of semen characteristics-spermiogram-includes estimation of the percentage of motile sperm; however it does not provide quantitative informations about sperm movement characteristics, except under the form of qualitative appreciations (slow, sluggish, yawing, non progressive, etc.). Flagellar function is indeed directly involved in the migration of spermatozoa through the female genital tract, and in the fertilization process by itself (migration through the zona pellucida requires special motility state, generally called “hyperactivation”). Sperm flagellar movements can now be indirectly investigated by analysing movements of sperm head, which are more easily detectable under phase contrast illumination: video signals are digitalized then sperm tracks are reconstructed by the computer from coordinates of sperm centroids (these systems are called “computer-assisted semen analysis” or “CASA”). CASA systems are now so performing and rapid that sperm movement analysis (SMA) can be proposed in the same time of routine semen analysis. However SMA, together with other functional tests, offer more interest in some particular situations as unexplained infertility, or unexpected failure of IVF. Numerous studies have tried to identify the most discriminant parameters, generally by means of multiple regression analysis. The interpretation of litterature data is difficult because of several differences in the protocol design, concerning either the measurements conditions (before or after sperm washing and selection) or the nature of the functional test: migration into cervical mucus, zona-free hamster egg penetration, IVF, etc. Moreover, the most discriminant factors are generally represented by classical parameters as % of normal forms or of motile sperm. In the present study we showed that only the factor “% of motility” allowed a significant discrimination according to different classes of fertilization rate (FR) in an IVF system. FR increased with hyperactivation rate (HA), but the statistical test was not significant. However, the more numerous cases of IVF failure were found in the group corresponding to very low HA rate (0–5%). We conclude that one major interest of SMA is to reveal some flagellar dyskinesia (i.e. corresponding to low values of amplitude lateral displacement of the head, or straight line velocity). These cases could then benefit of assisted reproductive techniques well adapted to this motion dysfunction, as subzonal insemination (SUZI) or intra-cytoplasmic sperm injection (ICSI).     

Semen characteristics of the swamp buffalo (Bubalus bubalis)

The semen characteristics were studied in 182 ejaculates collected with a bovine artificial vagina from five swamp buffalo (Bubalus bubalis) bulls. The mean values were: volume, 2.9 ml; general motility, 70.7%; live (unstained) sperm, 86.5%; abnormal sperm, 10.3%; intact acrosomes, 82.4%; sperm concentration, 1.06 × 10⁹cells/ml and total sperm/ejaculate, 3.18 × 10⁹cells/ml. Among the sperm abnormalities noted were “knobbed” acrosome, abaxial implantation, the “Dag” defect and the corkscrew midpiece. There were no significant (P > 0.05) monthly variations for any of the semen characteristics studied.     

Automatic annular laser trapping: a system for high‐throughput sperm analysis and sorting

An automatic microscope system is designed to study the response of sperm motility to an annular laser trap. A continuous annular laser trap provides a parallel way to analyze and sort sperm based on their motility and to study the effects of laser radiation, optical force and external obstacles. In the described automatic microscope system, the phase contrast images of swimming sperm are digitized to the computer at video rates. The microscope stage is controlled in real‐time to relocate the sperm of interest to the annular trap with a normal or tangential entering angle. The sperm is continuously tracked and the swimming behavior is identified. Using this system, parallel sorting on human and gorilla sperm are achieved and threshold power levels separating the “fast” group and the “slow” group are compared for those two species. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Ranking the indicators of building performance and the users’ risk via Analytical Hierarchy Process (AHP): Case of Malaysia

The need to optimise the performance of buildings has increased consequently due to the expansive supply of facilities in higher education building (HEB). Hence, a proper performance assessment as a proactive measure may help university building in achieving performance optimization. However, the current maintenance programs or performance evaluation in the HEB is a systemic and cyclic process where maintenance is considered as an operational issue and not as opposed to a strategic issue. Hence, this paper proposed a Building Performance Risk Rating Tool (BPRT) as an improved measure for building performance evaluation by addressing the users' risk in health and safety aspects. The BPRT was developed from the result of a rating index using the Analytical Hierarchy Process (AHP) method. A total of 12 facilities management (FM) experts and practitioners were involved in the rating process. The subjective weightings were analysed by using the AHP computer software programme, the Expert Choice 11. The result of the AHP had successfully assigned weighting scores to all performance-risk indicators, with five indicators ranked as the most critical indicators; structural stability (14.9%), fire prevention services (9.1%), building-related illnesses (7.4%), emergency exits (6.8%), and electrical services (6.3%). The final indication to the assessed building using the BPRT provided a rating classification in terms of the following: “Excellent”, “Good”, “Medium”, “Low”, or “Poor”, which suggested further actions to improve the performance of the building, as well as to mitigate the users’ health and safety risks. Hence, the establishment of the BPRT was successfully employed as an aid of improvement towards the current performance assessment of HEB by emerging the concept of building performance and risk into a numerical strategic approach.     

Complex adaptive traits between mating behaviour and post-copulatory sperm behaviour in squids

Emergence of male dimorphism within a species is the evolutionary process of disruptive selection. In squids, two types of male mating behaviour, known as alternative reproductive tactics (ARTs), are causally associated with adult body size. Males inseminate promiscuously with the same females; large “consort” males internally, and small “sneaker” males externally. Previously we found that in Heterololigo bleekeri, sneaker (but not consort) spermatozoa are able to swarm by sensing self-emitted CO₂. This suggests that a swarming trait might have arisen in sneakers as a “sperm cooperation” strategy among sibling sperm in order to compete with consort males, or as a consequence of adaptation to external fertilization. To address these possibilities, we examined six species where three patterns of insemination are present, namely, only internal, only external, or both ARTs. In three species that employ both ARTs (H. bleekeri, Loligo reynaudii and Uroteuthis edulis), sneaker spermatozoa always exhibited self-swarming capacity. In Idiosepius paradoxus and Todarodes pacificus, which use only external insemination, spermatozoa formed a swarm. However, in Euprymna morsei, which use only internal insemination, sperm were unable to swarm. These results suggest that the self-swarming trait is likely to be linked to the mode of insemination rather than the alternative strategy used by sneaker males. Thus we propose a new hypothesis in which cooperative sperm behaviour has evolved not only through kin selection against sperm competition risks, but also through adaptation to the insemination/fertilization environment.     

REVIEW: Is the “flagellate” pattern of spermatogenesis plesiomorphic in Metazoa?

Summary

The phenomenon of “flagellate spermatogenesis” typically known among marine invertebrates with “primitive” sperm and external or external-internal fertilization is discussed. It is suggested that “flagella bearing” in early germinative cells might be explained by plesiomorphic similarity between these cells and flagellate somatic epithelial cells. The early germ cells of more apomorphic multicellular animals using internal fertilization with “modified” and “aberrant” sperm typically have no flagella and this organelle, as the sperm tail, first appears in spermatids. It is speculated that the “flagellate” pattern typifies the basal level and that the transition between “flagellate” and “specialized” spermatogenesis constitutes a significant step in evolution.     

Changes in the motility patterns of spermatozoa from the rabbit epididymis as assessed by computer-aided sperm motion analysis

Sperm maturation in the epididymis includes changes in their potential for motility that enables spermatozoa to reach the egg and penetrate its investments. The motility characteristics of spermatozoa from the testis, the epididymis, and vas deferens of the rabbit were investigated by computer-assisted sperm analysis (CASA). Various forms of motility were displayed by sperm from different regions of the epididymis released into incubation medium Testicular sperm were motile, although nonprogressive. The maximum percentage motility was expressed by sperm in the proximal cauda epididymidis, and forward progression was developed by spermatozoa from the distal caput. Once forward progression was established, the curvilinear velocity was about the same for sperm from all regions of the tract, whereas straight-line velocity increased between the mid-corpus and cauda and paralleled the decline in lateral displacement of the head. The maintenance of motility in vitro was best maintained by sperm from the distal regions of the tract although sperm from the distal caput maintained motility better than sperm from the proximal and midcorpus regions. Analysis of the motile sperm cells revealed several types of trajectories (“irregular,” “small circular,” “large circular and arcs,” “jagged” and “straight-line”) that were analyzed by discriminant analysis using the variables generated by CASA. Accuracy of classification varied from 70% to 96%, depending on the type of track. The classification function was then applied to the changes that occurred during incubation and showed that irregular trajectories gave way to small and then large circular tracks and progressive forms as sperm matured. © 1996 Wiley-Liss, Inc.     

INDIVIDUAL VARIATION IN SPERM COMPETITION SUCCESS OF YELLOW DUNG FLIES,SCATOPHAGA STERCORARIA

Intraspecific variation in the proportion of offspring sired by the second male to mate with a female (P₂) is an aspect of sperm competition that has received little attention. We examined variation in the sperm competition success of individual male dung flies, Scatophaga stercoraria. In unmanipulated matings, copula duration was dependent on male size with smaller males copulating for longer. A principal component analysis was used to generate uncorrelated scores based on a male's size and copula duration. Using these scores demonstrated that P₂ values were dependent both on the relative size and copula durations of competing males. When copula duration was held constant, the success of an individual male increased as his body size, relative to the first male, increased. We interrupted copulations of “large” and “small” second males and fitted the resultant P₂ values to a linear model of sperm competition with unequal ejaculates. The data fit well to a model of sperm displacement in which sperm mix quickly on introduction to the sperm stores. Furthermore, they show that “large” males have a greater rate of sperm displacement than “small” males. The levels of prey availability during testis maturation may influence a male's success in sperm competition although his immediate mating history does not. We show why an understanding of variation in sperm competition success is important for understanding the mechanisms and evolutionary significance of sperm competition.     

An electrical block is required to prevent polyspermy in eggs fertilized by natural mating of Xenopus laevis

In 27% DeBoer's saline (DBS), which yields maximum fertility rates, Xenopus eggs fertilized in vitro are monospermic, regardless of sperm concentration. One block to polyspermy (the “slow” block), described previously, occurs at the fertilization envelope that is elevated in response to the cortical reaction. This paper describes properties of an earlier, “fast” block at the plasma membrane and evaluates the functional significance of the two blocks at physiological sperm concentrations in natural mating conditions. Unfertilized eggs have a resting membrane potential of ?19 mV in 27% DBS. Fertilization triggers a rapid depolarization to +8 mV (the fertilization potential, FP); the potential remains positive for ca. 15 min. Activation of eggs with the ionophore, A23187, produces a slower but similar depolarization (the activation potential, AP). As in other amphibian eggs, the FP appears to result from a net efflux of Cl^?, since the peak of the FP (or the AP in ionophore-activated eggs) decreases as the concentration of chloride salts in the medium is increased. In 67% DBS no FP or AP is observed; eggs fertilized in 67% DBS become polyspermic and average 2 sperm entry sites per egg. In the 5–37 mM range, I^? and Br^?, but not F^?, are more effective than Cl^? in producing polyspermy. In 20 mM NaI the plasma membrane hyperpolarizes in response to sperm or ionophore; 100% levels of polyspermy and an average of 14 sperm entry sites per egg are observed. NaI does not inhibit or retard elevation of the fertilization envelope; the cortical reaction and fertilization envelope are normal in transmission electron micrographs. In 67% DBS, which also inhibits the fast block, the slow block was estimated to become functional 6–8 min after insemination. Eggs fertilized by natural mating in 20 mM NaI exhibit polyspermy levels of 50–90% and average 5 sperm entry sites per egg. Since eggs become polyspermic when fertilized by natural mating under conditions that inhibit the fast, but not the slow, block to polyspermy, we conclude that the fast block is essential to the prevention of polyspermy at the sperm concentrations normally encountered by the egg.     

To be or not to be [fertile], that is the question

Background

According to our literature analysis, there are no data focused on spermatozoa emotional representations in childless men and data on the emotional repercussions of a diagnosis of infertility on men are still scarce. Thus, in this work, we investigated what the presence or absence of spermatozoa in the semen symbolize for men.

Material and methods

To answer this question, 441 childless heterosexual men participated in an anonymous, prospective, Internet-based survey.

Results

In response to the question “What would having a high or normal sperm count symbolize for you?” the most frequent answer was “ability to father a child”. Men living with a partner were significantly more likely than single men to answer “ability to father a child” (p?<?0.05) and less likely to answer “virility” and/or “ability to have an erection/ejaculation” (p?=?0.001). In response to the question “If you found out that you had a low sperm count or no spermatozoa at all, how would you feel?”, most of the men stated that they would be disappointed. Men living with a partner were more likely to state that they would feel ashamed (p?<?0.05) or guilty with regard to their partner (p?<?0.0001).

Conclusions

These preliminary results should help us to improve (i) the way that male infertility is announced (it is easier to find the right words if one understands the possible importance of having a high sperm count) and (ii) the psychological, marital and sexual counselling provided to men with a diagnosis of infertility.

     

Chromosomes of the caryophyllidean tapeworm Glaridacris laruei

The chromosomes of the monozoic tapeworm Glaridacris laruei, from 4 locations in New York State, were studied in leucobasic fuchsin stained squashes of testes and vitelline cells. The diploid chromosome number is 16. Metaphase figures from vitelline cells consist of 3 pairs of metacentrics (“V's”), 4 pairs of acrocentrics (“rods”), and 1 pair of submetacentrics (“J's”). The complement is characterized by a pair of metacentrics 9 μm long, representing 11.5% of the total chromosome length. The shortest are acrocentrics, 2–4 μm long. Meiosis was observed only in spermatogenesis, which proceeds as usual with normal sperm formed after 2 meiotic divisions. Colchicine pretreatment did not facilitate analysis of chromosomes. The scarcity of cell division in 2 populations of G. laruei suggests a possible mitotic rhythm or temperature effect on cell division. Similarities were observed between the the complements of G. laruei and Hunterella nodulosa (2n = 14). A theoretical idiogram, constructed from that of G. laruei, closely resembles H. nodulosa, indicating that there may be a close cytological relationship between these phenotypically different caryophyllids. An idiogram and photographs of chromosomes supplement the paper.     

Ploidy determination of three Kappaphycus alvarezii strains (Rhodophyta, Gigartinales) by confocal fluorescence microscopy

Kappaphycus alvarezii is a red alga that is commercially important as a source of carrageenan. Since K. alvarezii presents large phenotypic plasticity and rarely develops reproductive structures in culture, identification of gametophytic and tetrasporophytic phases in cultivation systems are difficult. The aim of this study was to determine the ploidy of three K. alvarezii strains previously identified as brown “tetrasporophyte”, brown “gametophyte” and “Edison de Paula” (EP). Nuclei from these strains were stained with DAPI, and analyzed using confocal fluorescence microscopy and ImageJ software. The brown “tetrasporophyte” had the highest nuclear fluorescence intensity, consistent with a diploid tetrasporophyte (2N). The brown “gametophyte” and “EP” strains had nuclear fluorescence intensities of 55.78% and 57.10% in relation to the tetrasporophyte, respectively, consistent with haploid gametophytes (N). The present study demonstrated that this technique can be used as a rapid and effective tool to distinguish between haploid (gametophytic) and diploid (tetrasporophytic) plants of K. alvarezii, in addition to help identify new strains developed through alterations of ploidy level.     

Improved cryosurvival of stallion spermatozoa after colloid centrifugation is independent of the addition of seminal plasma

Addition of seminal plasma (SP) prior to cryopreservation may influence stallion sperm cryosurvival. The objective of this study was to investigate the addition of pooled SP from “good” or “bad” freezer stallions to spermatozoa selected by single layer centrifugation (SLC) prior to cryopreservation on post-thaw sperm quality. Semen from 12 stallions was collected; 5 mL was frozen as control (C) and the remainder was processed by SLC to remove SP and was divided into three aliquots: i) SLC sample without SP (SLC); ii) SLC plus pooled SP from “good freezer” stallions (SLC-GF); iii) SLC plus pooled SP from “bad freezer” stallions (SLC-BF). After thawing, the following parameters were evaluated: chromatin integrity (DNA fragmentation index; %DFI), mitochondrial membrane potential (MMP), membrane integrity (MI), reactive oxygen species (ROS) and sperm kinematics. The %DFI was reduced (P < 0.0001) in SLC samples compared to controls. The SLC group showed a lower proportion of spermatozoa with low MMP and a higher proportion of spermatozoa with high MMP than other groups (P < 0.0001), and had lower hydrogen peroxide content than control. Sperm kinematics were not different. In conclusion, selection by SLC prior to cryopreservation improved post-thaw sperm quality; inclusion of SP from “good” and “bad” freezer stallions did not have an additional beneficial effect.     

Modelling the vasculature of the stem of <Emphasis Type="Italic">Cyperus involucratus</Emphasis> Rottb.: evidence for three patterns of vascular bundles

Main conclusion

Three independent patterns of vein formation in Cyperus involucratus Rottb. were identified based on rare spontaneous interruptions of scape vein development. A number of developmental anomalies of vascular bundles in Cyperus involucratus Rottb. were identified and they include “turnabout”, “absent”, “twins”, “doublet”, amphivasal and various stages of “arrested”. These were used to develop a computer program to explain the three vasculature patterns of the scape of (a) ordered deployment of vascular bundles, (b) arrangement of tissues within vascular bundles and (c) orientation of vascular bundles with respect to stem edge. The computer model is a cell-by-cell determination of cell types and facet states.

     

When do sperm of the sea urchin,Pseudocentrotus depressus,undergo the acrosome reaction at fertilization?

Jelly coats of the sea urchin, Pseudocentrotus depressus, were stripped off the eggs, and the eggs were “inseminated.” After penetration through the isolated jelly hull, sperm swarmed in the cavity previously occupied by the egg. Electron microscopic examination could not detect any sperm with reacted acrosome. Observation was also made of the sperm penetrating through the intact jelly coat-egg complex. Although a number of sperm were examined in ultrathin sections, only those attached to the vitelline layer had undergone the acrosome reaction; those sperm embedded in jelly but not attached to the vitelline layer had not undergone the acrosome reaction. The sequence of events in fertilization of this species and of other echinoids is discussed.     

Evaluation de l’apport de la méthode d’observation des spermatozoïdes à fort grossissement en ICSI

Due to the growing interest in the method of high-magnification sperm observation and selection proposed for the specific indication of ICSI failure, the authors evaluated the technique in unselected ICSI. The aim of this study was to evaluate the relevance of Motile Sperm Organelle Morphology Examination (MSOME) compared with usual selection performed in ICSI. In a series of conventionally selected sperm for ICSI, the number with an abnormal appearance on high magnification was determined and the predictive value of this parameter on ICSI outcome was assessed. The study included 25 successive unselected ICSI attempts in the IVF Laboratory of Poissy Hospital (France). ICSI were performed according to usual protocols used in the laboratory. Twenty five motile spermatozoa of the migrated fraction, still available after ICSI, and “injectable— according to conventional morphology assessment in ICSI (“normal” or “as normal as possible” with magnification of ×200–400) were assessed by MSOME (higher than ×4500) and classified according to criteria adapted from Bartoov’s work and taking into account David’s sperm morphology classification. We compared the results of MSOME and ICSI results. In this small series of ICSI with diverse indications, we found very high frequencies of abnormalities (more than 70%), particularly nuclear vacuoles. No predictive value of the morphology of sperm assessed with high magnification (including vacuoles) was found for fertilization rate, embryo quality and ICSI outcome. In contrast with previous reports, pregnancies were obtained with very abnormal sperms. In this series of unselected ICSI, nuclear vacuoles do not seem to have a pejorative impact on pregnancy outcome. This study raises several perspectives. It would be interesting to understand the “anatomical” basis for vacuoles observed with MSOME and their meaning. The question of the phenotype-genotype relation, i.e. the possible correlation between sperm morphology and genetic content could be investigated. Finally, a prospective analysis should be performed in clearly defined indications to validate the potential applications of the method for high-magnification sperm observation and selection.     

Alterations in primate sperm motility with maturation and during exposure to theophylline

Micropuncture was used to collect pure suspensions of sperm from the caput and cauda regions of chimpanzee epididymides, which were analyzed with a Motion Analysis VP-110. Sperm recovered from the caput region showed no forward motility. Incubation of these sperm with cauda epididymal fluid affected motility in 62%–90% of the sperm. Dilution of cauda sperm into buffer containing >50 mM theophylline resulted in immediate initiation of progressive forward motility. Although this motility was maintained by at least 50% of the sperm for over 5 hr, these “activated” caput sperm did not penetrate zona-free hamster ova. These data show that sperm from the caput epididymis of the chimpanzee have the capacity for normal motility but do not have the capacity to bind to and penetrate an ovum. Cauda epididymal chimpanzee sperm were motile at the time of recovery and this motility was maintained for over 5 hr. These sperm penetrated both hamster zona-free ova and intact chimpanzee ova. These data show that sperm from the cauda epididymis of the chimpanzee have the capacity for normal motility and also have the capacity to bind to and penetrate an ovum. This is the first use of computer assisted analysis to quantify motility in maturing nonhuman primate sperm.     

Studies on mixing in horizontal rotating tubular bioreactor

A horizontal rotating tubular bioreactor (HRTB) is a combination of a “thin-layer bioreactor” and a “biodisc” reactor. Its interior is divided by O-ring shaped partition walls. Mixing properties of this new type of the bioreactor were investigated by using a temperature step method. The mixing simulations were done by Runge-Kutta-Fehlberg numerical integration. Adjustable parameters of the “spiral flow” model were optimised by Monte-Carlo method. In this investigation, the structured “spiral flow” model (containing four adjustable parameters) was tested in a wide range of experimental conditions. The results show that the structured “spiral flow” model is capable to describe the mixing in HRTB in the whole range of both bioreactor operational parameters (n and D).     

Design of an automated temperature mapping system for ultrasound or microwave hyperthermia

An automated temperature mapping system was designed to accomplish the following goals: remote control mapping; a maximum position error of 0.5 mm; mapping simultaneously on several channels; real-time screen display on a dedicated computer; to be inexpensive; and have a simple patient interface and set up. A four channel, microstepper system was fabricated for less than $1000 and controlled by an IBM-AT computer. The system utilizes direct drive of Luxtron fibre-optic probes fed through thin flexible Teflon^® tubing which allows for patient movement. The driving and control software were written in the programming language “C”. Mapping parameters for each independent channel include start and stop positions and map increment. The software permits the user to automatically find the maximum temperature along a track in three passes of 2.0, 1.0 and 0.5 mm steps. The latter two passes take five or seven readings centred about the maximum of the previous pass. A high resolution monitor plots the temperatures in real time, overlaying the previous map in a new colour. A screen dump was written to drive a colour printer with the plot information. The computer evaluates each plot to safeguard against any shift in the maximum location. Visualization of orthogonal pullbacks provides rapid feedback and aids in the repositioning of superficial hyperthermia transducers. The time saved over the previous manual mapping methods easily justifies the additional set up time.