bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polyclonal antibodies to a 32‐KDA deglycosylated polypeptide from porcine zonae pellucidae will prevent human gamete interaction in vitro
Authors: Henderson Colin J. , Braude Peter , Aitken R. John 
Published: February 2005

AbstractThe major deglycosylated polypeptides of the porcine zona pellucida (ZP), with molecular masses of 66, 52, 36, and 32 kDa, were purified to homogenity with one‐dimensional sodium dodecyl sulphate/polyacrylamide gel electrophoresis (SDS/PAGE). Immunofluorescence studies demonstrated that antibodies to the DGZP fraction, and the 66‐ and 32‐kDa polypeptides, bound predominantly to the outer ZP; however, only the first two of these antisera formed an immunoprecipitate around the outer human ZP. In immunoblotting experiments using polyclonal antisera raised to these molecules all four polypeptides exhibited cross‐reactivity with each other and their parental glycoprotein families (ZP 1–4). In addition, the antisera were tested in an in vitro human gamete bioassay to determine their contraceptive potential; antibodies to the 32‐kDa deglycosylated polypeptide inhibited human gamete interaction to the greatest extent, 5.3% (± 1.2%), relative to a control value of 100%.
Influence of proteins in rat cauda epididymidal lumen fluid on cauda sperm motility
Authors: Turner T. T. , Reich G. W. 
Published: February 2005

AbstractRat cauda epididymidal spermatozoa are kept quiescent in the cauda lumen by a protein fraction termed “immobilin”, but it has not been shown whether or not this activity is unique to the immobilin fraction. Cauda fluid was subjected to gel filtration chromatography and the eluents contributing to three peaks of absorbance at A280 were pooled, lyophylized, and reconstituted at equivalent concentrations. Their relative viscoelasticity and their effects on sperm motility were determined. Peak 1 (P1), containing proteins > 400 kd, retained the greatest sperm‐immobilizing activity, but P2 and P3 also had sperm‐immobilizing activity related to their viscoelasticity. P1 and an immobilin fraction obtained by ultracentrifugation of rat cauda fluid were generally similar in their sperm‐immobilizing activity, viscoelasticity index, electrophoretic patterns, and binding characteristics to Concanavalin A; thus, the sperm‐immobilizing factor obtained by gel filtration chromatography and the immobilin fraction obtained by centrifugation are believed to be the same products. Further, it was shown that intraluminal testicular fluids did not inhibit cauda sperm motility even at epididymal‐like protein concentrations; thus, it is believed that the sperm‐immobilizing factor(s) is of epididymal, not testicular, origin.
Toxicity potential of residual ethylene oxide on fresh or frozen embryos maintained in plastic straws
Authors: Schiewe Mitchel C. , Schmidt P. M. , Pontbriand D. , Wildt D. E. 
Published: February 2005

AbstractThe toxic effects of residual ethylene oxide (EtO), a frequently used gas‐sterilant, on embryos either frozen for long‐term purposes or stored acutely for 30 min to 9 hr in a fresh condition in 0.25‐ml straw containers were evaluated. In Experiment 1, fresh embryos were frozen (using conventional technology) in straws previously aerated for 0 hr to 8 mo after EtO sterilization. With the exception of the 8‐mo group in which survival and quality ratings were depressed, embryo viability was not affected significantly by short‐term prefreeze and post‐thaw exposure to EtO residues. Experiment 2 was conducted to analyze the influence of prefreeze exposure to EtO residues on embryo development in vitro for embryos temporarily stored in previously sterilized straws aerated for different intervals. Compared to non‐EtO‐sterilized control straws, the development, quality, and viability of embryos exposed to EtO‐treated straws were compromised (p < 0.05) as the aeration interval decreased and the exposure interval increased. The combined results of both experiments indicate that EtO‐treated straws can be used to cryopreserve gametes efficiently, but only if the aeration interval is ≥72 hr and the prefreeze duration of exposure is ⩽3 hr.
Hamster sperm motility transformation during development of hyperactivation in vitro and epididymal maturation
Authors: Suarez Susan S. 
Published: February 2005

AbstractThe transformation of hamster sperm motility during capacitation in vitro and during maturation in the caudal epididymis was analyzed and compared using videomicrography. Sperm recovered from the distal portion of the caudal epididymis, as well as ejaculated sperm recovered from the uterus exhibited low amplitude, planar flagellar beating. By 3 hr of incubation under capacitating conditions, the caudal epididymal sperm were swimming in helical patterns apparently produced by significantly increased acuteness of flagellar bending and by torsion seen as abrupt, periodic turning of the head. By 4 hr, most sperm were hyperactivated, swimming in circles resulting from asymmetrical, planar flagellar bending that was significantly more acute than the preceding patterns. When motility parameters of fresh sperm were compared with those of sperm swimming in the transitional helical pattern and with hyperactivated sperm, transitional sperm had significantly higher net and average path velocities than the others, indicating that they covered space at the greatest rate. This suggests that the transitional phase plays an important role in sperm transport. Sperm recovered from the proximal region of the caudal epididymis, near the corpus, swam in either the helical or hyperactivated patterns, or a mixture of the two. The means of their flagellar curvature ratios and linear indices were intermediate between helical and hyperactivated mean values. Thus, sperm undergoing final maturation in the caudal epididymis reverse the pattern of development of hyperactivation. Also, the development of hyperactivated motility must therefore entail induction of a preexisting potential for flagellar movement, rather than a maturational process.
The role of membrane‐active lipids in the protection of ram spermatozoa during cooling and storage
Authors: Holt W. V. , North R. D. 
Published: February 2005

AbstractThe interactions of ram spermatozoa with exogenous liposomes of varying composition were studied, with the aim of examining the mechanisms by which some lipids protect against cold‐induced damage during cryostorage. Liposomes containing various preparations of phosphatidylcholine and cholesterol enhanced sperm survival during storage at 5°C, both in terms of motility and acrosomal integrity. A membrane‐fluidizing agent, A2C, was slightly deleterious in this respect. Cholesterol‐containing liposomes were not superior in their effects to those prepared without cholesterol. Thus stabilization of the plasma membrane by cholesterol loading may be unimportant.When sodium vanadate was used as a functional probe of membrane integrity, the cryoprotective effects of lipids were apparent despite increased plasma membrane permeability. Incubation of spermatozoa with positively charged liposomes, containing stearyl‐amine, caused considerable loss of motility and acrosomal damage, coupled with cellular aggregation. There was also some evidence that the presence of calcium lessened the effectiveness of liposomes in protecting spermatozoa against damage during cooling.
Differential distribution of the P1 and P2 protamine gene sequences in eutherian and marsupial mammals and a monotreme
Authors: Johnson Paula A. , Yelick Pamela C. , Liem Hetty , Hecht Norman B. 
Published: February 2005

AbstractAt the protein level, the P1 protamine is the predominant form of mammalian protamine, present in all mammalian spermatozoa analyzed to date. An additional variant, the P2 protamine, has been detected only in spermatozoa of the mouse, hamster and human. Southern blot analysis of a group of restriction enzyme‐digested mammalian DNAs has revealed the presence of sequences homologous to the P1 and the P2 mouse protamine genes in diverse species. In agreement with protein studies, nucleotide sequences homologous to the mouse P1 protamine cDNA are widespread, being present in the genomic DNAs of human, rat, dog, ram, horse, bull, hamster, baboon, flying fox (megabat), microbat, boar, North American opossum, and wallaby. Although we detect genomic sequences with strong homology to the mouse protamine 2 cDNA in rat and hamster, we also find weaker but reproducible hybridization to the genomic DNA of human, boar, dog, bull, microbat, wallaby, and platypus. With the exception of the human, the P2 protamine has not been detected in the spermatozoa of these latter species.
Ultrastructure of spermatogenesis in the sea star, Asterina minor
Authors: Yamagata Atsuko 
Published: February 2005

AbstractThe ultrastructural features of spermatogenesis were investigated in the hermaphroditic sea star Asterina minor. The primordial germ cells in the genital rachis contain small clusters of electron‐dense material (nuage material) and a stack of annulate lamellae. They also have a flagellum and basal body complex situated close to the Golgi complex. After the development of the genital rachis into the ovotestis, spermatogenic cells increase in number and differentiation begins. Nuage material is observed in spermatogonia, but it gradually disappears in spermatocytes. The annulate lamellae do not exist beyond the early spermatogonial stage. By contrast, a flagellum and basal body complex are found throughout spermatogenesis. The Golgi‐derived proacrosomal vesicles appear in the spermatocyte and coalesce to form an acrosomal vesicle in the early spermatid. The process of acrosome formation is as follows: (1) a lamella of endoplasmic reticulum (ER) continuous with the outer nuclear membrane encloses the posterior portion of the acrosomal vesicle; (2) the vesicle attaches to the cell membrane with its anterior portion; (3) periacrosomal material accumulates in the space between the acrosomal vesicle and the ER; (4) the nucleus proper changes its features to surround the acrosome; (5) amorphous, electron‐dense material is deposited under the electron‐dense disk; and (6) the nucleus forms a hollow opposite the electron‐dense material.
Quantitative comparison of the passage of homologous and heterologous spermatozoa through the uterotubal junction of the golden hamster
Authors: Smith T. Timothy , Koyanagi F. , Yanagimachi R. 
Published: February 2005

AbstractA quantitative method was used to determine whether the spermatozoa of foreign species could pass through the uterotubal junction (UTJ) of the hamster as efficiently as homologous (hamster) spermatozoa. Estrous female hamsters were artificially inseminated with epididymal spermatozoa of homologous and heterologous (foreign) species. The number and distribution of spermatozoa in the oviduct were determined several hours after insemination (shortly before ovulation). The passage of immotile (dead) hamster spermatozoa through the UTJ was also examined.It was found that the spermatozoa of all foreign species tested (rat, mouse, guinea pig, and rabbit), as well as immotile hamster spermatozoa, could pass through the UTJ but did so in much smaller numbers compared to live hamster spermatozoa. This was not specifically due to poor survival of foreign spermatozoa in the hamster uterus, as the viability of all inseminated spermatozoa (including hamster spermatozoa) was considerably reduced by 1 h after insemination. While a large number of live hamster spermatozoa were distributed throughout the caudal isthmus at the time of examination, none or only a very few foreign spermatozoa had advanced this far. The few foreign and immotile spermatozoa that reached the caudal isthmus were confined to the first ascending loop of this segment. Some possible causes for the small number and retarded advance of foreign spermatozoa in the hamster oviduct were discussed.
Fertilizing potential of acrosome‐defective sperm following microsurgical injection into eggs
Authors: Lanzendorf S. , Maloney M. , Ackerman S. , Acosta A. , Hodgen G. 
Published: February 2005

AbstractEjaculates from three infertile men were examined ultrastructurally and found to include a high number of amorphous acrosomeless spermatozoa. Two of the patient's spermatozoa exhibited the typical characteristics of round‐head syndrome—spherical‐shaped heads completely absent of acrosome and postacrosomal sheath. The semen of the third patient was found to contain a mixture of round‐headed and irregularly shaped acrosomeless sperm and a small percentage of normal acrosome‐intact sperm. Previous studies have shown that acrosomeless sperm do not have the ability to bind or penetrate zona‐free hamster eggs (Weissenberg et al., Syms et al.). In an attempt to determine if such amorphous sperm are capable of decondensation and pronuclear formation, sperm of all three men were microsurgically injected into zona‐intact hamster eggs. All of the sperm injected were found to be capable of decondensation or pronuclear formation, suggesting that if the inability to penetrate an egg is bypassed, the sperm of these infertile men are capable of participating in the early events of fertilization.
Chimerization of highly asynchronous murine blastomeres: Developmental alteration?
Authors: Prather R. S. , First N. L. 
Published: February 2005

AbstractPrevious studies have shown that early embryos contain information that can alter the developmental fate of adjacent cells and transferred nuclei. In this report we show that a specific combination of cells from early murine embryos, a single blastomere from an eight‐cell embryo placed under the zona pellucida with a two‐cell embryo, results in a difference in incorporation of 3H‐uridine and expression of two protein bands between the chimeric treatment group and the nonchimeric controls, a single blastomere from an eight‐cell embryo in a separate zona pellucida and a two‐cell embryo. The incorporation of 3H‐uridine in the chimeric group and nonchimeric control group was significantly different at 45 hours after chimerization (P < .02). A stage‐specific protein band (52k) on a polyacrylamide gel detected with fluorography was found to be qualitatively different (present more often; P < .01) and another stage‐specific protein band (48k) was found to be quantitatively different (more protein; P equals; .07) in the chimeric treatment vs. the nonchimeric controls at 45 hours after chimerization. These results suggest communication between the cells resulting in a change in their incorporation of uridine and protein synthetic profiles.
DNA content of spermatozoa in different genetic lines of turkeys
Authors: Lamošová D. , Baumgartner J. 
Published: February 2005

AbstractThe variability of DNA content in turkey spermatozoa of four different lines and its correlation with body weight and sperm concentration were studied. In lines selected for lower body weight the DNA content was 2.034 and 2.036 pg per spermatozoon. In lines selected for higher body weight the DNA content was 2.267 and 2.370 pg per spermatozoon. Sperm concentration in 1 mm3 of semen, however, was higher in lines with a lower body weight (6.08–6.21 million) in comparison with lines selected for higher body weight (5.46–5.67 million). The correlations between the DNA content and sperm concentration were negative (r ranged from −.457 to −.860).
Actin synthesis is not regulated by granulosa cells in mouse growing and preovulatory oocytes
Authors: Canipari R. , Bevilacqua A. , Colonna R. , De Felici M. , Mangia F. 
Published: February 2005

AbstractThe synthesis and intracellular distribution of actin were studied in isolated dictyate and metaphase II mouse oocytes by (1) sodium dodecyl sulfate‐polyacrylamide gel electrophoresis of newly synthetized oocyte protein and (2) cytochemical F‐actin labeling by fluorescent phalloidin. Unpermeabilized, fully grown oocytes bound phalloidin intensely at the level of the zona pellucida (ZP), such ZP‐associated actin representing a significant portion of total actin found in these cells. In contrast, phalloidin binding to ZP was very low in growing oocytes and was undetectable in ovulated, metaphase II eggs. When ZP‐associated actin of fully grown oocytes was removed by prolongedly exposing oocytes to α‐chymotrypsin, the amount of newly synthesized actin displayed by cumulus‐enclosed oocytes was reduced to a level comparable to that shown by oocytes isolated from granulosa cells. We demonstrate that ZP‐associated actin belongs to granulosa cell processes that remain within the ZP as a consequence of oocyte isolation procedures. We conclude that actin synthesis of mouse oocytes is not regulated by granulosa cells.
Viability of mouse half‐embryos in vitro and in vivo
Authors: Lawitts Joel A. , Graves Charles N. 
Published: February 2005

AbstractMouse embryos at the 2‐, 4‐, 8‐cell, and morula stage were divided in half by using microsurgical procedures and were either grown in vitro up to the blastocyst stage or transferred at the late morula stage into the uteri of pseudopregnant recipients. A relatively high percentage of the half embryos from 2‐cell (70%), 4‐cell (75%), 8‐cell (93%), or morula stage embryos (75%) developed into blastocysts in vitro. However, the overall development in vivo of half embryos was low, as 3%, 13%, 8%, and 1% of half embryos from the 2‐cell, 4‐cell, 8‐cell, and morula stages, respectively, developed into live fetuses.Embryos which were divided in half at different stages developed at different rates in vitro. This determined the stage of embryonic development at the time of transfer, which might have interacted with the stage of pseudopregnancy of the recipients to influence embryo survival in vivo.
Culture of in vitro fertilized rabbit ova
Authors: Keefer C. L. , Fayrer‐Hosken R. A. , Brown L. M. , Brackett B. G. 
Published: February 2005

AbstractEmbryonic development of in‐vitro fertilized rabbit ova was assessed following in‐vitro culture in four different serum supplemented media. A mixture of Basal Medium Eagle (BME) and Ham's F10 medium (1:1) provided better support for in‐vitro development than Ham's F10, BME, or regular acidic saline (RAS). In‐vitro embryonic development in the BME/Ham's F10 mixture was synchronous with in‐vivo development through at least 55 hr of culture. After 54 hr of culture, embryos transferred to the oviduct of a synchronous pseudopregnant recipient were able to implant at the same rate as simultaneously transferred embryos grown in vivo. BME/Ham's F10 supplemented with 10% newborn calf serum was highly supportive of rabbit embryo development following in‐vitro fertilization.
Refertilization in eggs of the sea urchin Strongylocentrotus purpuratus
Authors: Kubota Lynda F. , Carroll Edward J. 
Published: February 2005

AbstractTo determine the role of the sea urchin egg plasma membrane in the species‐specificity of fertilization, the ability of denuded activated eggs to be heterospecifically refertilized was determined. Our initial studies included evaluating the effectiveness of three commonly used methods of vitelline envelope (VE) removal using indirect immunofluorescence microscopy with antibodies directed against the VE. Unfertilized Strongylocentrotus purpuratus eggs were extracted with 0.01 M dithiothreitol (DTT) for 3 min or digested with 1.0 mg/ml pronase for 1 hr. Eggs were also fertilized, then diluted into a divalent‐free medium to produce thin, elevated envelopes (VE*s) that were mechanically removed by sieving the eggs through nylon mesh. We found that both DTT extraction and pronase digestion were not completely effective in VE removal, and mechanical removal methods gave rise to a mixed population of eggs, those that had their VEs removed and those with a collapsed envelope that was not detectable at the light microscope level. Therefore, a new method of VE removal was developed. Eggs with VE*s were prepared followed by treatment with 0.01 M DTT to solubilize the envelopes. Nearly 100% of the denuded activated eggs incorporated one or more homologous and heterologous sperm, suggesting that the egg plasma membrane does not function in determining the species‐specificity of fertilization.
Effect of cholesterol and phosphatidylcholine of different chain length on acrosome breakdown and fertilizing capacity of amphibian spermatozoa
Authors: Fontdevila Marina F. Diaz , Bloj Bernabe , Cabada Marcelo O. 
Published: February 2005

AbstractThe effect of different lipids on the fertilizing capacity of Bufo arenarum spermatozoa and on acrosome breakdown of Leptodactylus chaquensis spermatozoa was studied. Sonicated vesicles of egg yolk phosphatidylcholine (1 mM) were as effective as vesicles of egg yolk phosphatidylcholine:cholesterol (molar ratio 1:0.9) in inhibiting the fertilizing capacity of Bufo arenarum spermatozoa. This suggests that cholesterol depletion from the spermatozoa was not the cause of the fertility loss. Bufo arenarum spermatozoa were incubated with phosphatidylcholines with even chain length from 6 to 18 carbons. At a concentration of 0.01 mM, didecanoyl‐phosphatidylcholine reduced fertilizing capacity to 10% in a few minutes and to 0% within 60 minutes. Didodecanoyl‐phosphatidylcholine required 2 hours to reduce fertility to 10% and 4 hours to cause a 100% loss of fertilizing capacity. A concentration of didecanoyl‐phosphatidylcholine as low as 5 × 10−4 mM caused a more than 95% fertility loss in less than five minutes. At a concentration of 0.1 mM, didecanoyl‐phosphatidylcholine induced complete acrosome breakdown in Leptodactylus chaquensis spermatozoa in 15 minutes, whereas didodecyl‐phospatidylcholine required 2 hours. At a concentration 100‐fold lower didecanoyl‐phosphatidylcholine induced complete acrosome breakdown in 2 hours. Electron microscopic observations in both species showed loss of acrosome caused by the action of the didecanoyl‐phosphatidylcholine. Longer chain phosphatidylcholines exerted an inhibitory effect on Bufo arenarum spermatozoa fertilizing capacity at a higher concentration when in a vesicular form.
A major secretory protein from rat seminal vesicle binds ejaculated spermatozoa
Authors: Manco G. , Abrescia P. 
Published: February 2005

AbstractThe rat seminal vesicle produces large amounts of a protein‐rich fluid that greatly contributes to semen volume. RSV IV, a protein abundantly secreted from this gland, binds in vitro to rat epididymal spermatozoa. However, there is no evidence that this protein may have an in vivo role as a sperm‐coating antigen. We report in this paper that high‐molecular‐weight RSV IV immunologically related proteins can be detected on ejaculated spermatozoa, but not on epididymal spermatozoa. After incubation of purified RSV IV with ejaculated spermatozoa in freshly recovered semen or with epididymal spermatozoa in a medium containing the coagulating gland secretion, sperm‐bound proteins with analogous properties were detected. These results support the hypothesis that RSV IV is modified at ejaculation to an high‐molecular‐weight, sperm‐coating antigen.
Phagocytosis of sperm heads lacking the acrosomal process by unfertilized starfish oocytes
Authors: Kyozuka Keiichiro , Osanai Kenzi 
Published: February 2005

AbstractIn sperm of the starfish Asterina pectinifera, the acrosomal process and the flagellum were mechanically separated from the sperm head with a disperser. The sperm head fraction was then used to examine the direct interaction between the sperm head and the egg surface. Sperm heads lacking the acrosomal process and the flagellum did not fertilize oocytes, even after removal of the vitelline coat. Transmission electron microscopy showed that each denuded oocyte engulfed the sperm head without gamete membrane fusion. The sperm‐engulfing response, similar to phagocytosis, was induced without the mediation of the acrosomal process. The present results suggest that the process of sperm incorporation consists of two independent events, acrosomal process‐egg surface fusion and the phagocytotic movement of the egg surface.