bluuebunny/crossref_metadata_2025_split huggingface dataset:
A glycoprotein of oviductal origin alters biochemical properties of the zona pellucida of hamster egg
Authors: Oikawa Taneaki , Sendai Yutaka , Kurata Sho‐Ichiro , Yanagimachi Ryuzo 
Published: February 2005

AbstractEggs were isolated from ovaries and oviducts of the golden hamster and the components of zonae pellucidae were examined using density gradient SDS‐polyacrylamide electrophoresis. Zonae of ovarian eggs (ZP‐OVA) had three major components corresponding to the so‐called ZP‐1, ZP‐2, and ZP‐3. Zonae of recently ovulated eggs collected from oviducts (ZP‐OVI) had a 200–240 K component (ZP‐O) in addition to the three components present in ZP‐OVA. When ovarian and oviductal eggs were stained with FITC‐conjugated B. simplicifolia‐1 lectin (BS‐1), which specifically binds to alpha‐D‐galactose‐ or alpha‐N‐acetyl‐D‐galactosamine‐like terminal saccharide residues, ZP‐OVI was intensely stained, while ZP‐OVA was not. ZP‐OVA gained the ability to bind to BS‐1 after a brief treatment with oviduct extracts. These results suggest that biochemical properties of hamster zonae change after transport of eggs from ovary to the oviduct. The addition of the 200–240 K component of oviductal origin to preexisting zona components seems to be responsible for this change.
Effects of delayed mating on preimplantation embryos in spontaneously ovulated mice
Authors: Sakai Nobuyoshi , Endo Akira 
Published: February 2005

AbstractThe effects of delayed mating on mouse preimplantation embryos (78 ± 1 hours) were studied by setting up different mating periods in relation to the estimated time of spontaneous ovulation. Copulation occurred even in the late morning and early afternoon after the night of spontaneous ovulation. However, females mated in the early afternoon had no viable embryos at the time of laparotomy. Although embryonic development was not affected in the groups mated 6 or 10 hours after estimated ovulation, the percentage of degenerated embryos was increased in these groups. These results suggest that prolonged intervals between the estimated time of ovulation and mating have some deleterious effects on preimplantation embryos.
Characterization of actin isoforms in ejaculated boar spermatozoa
Authors: Casale Antonella , Camatini Marina , Skalli Omar , Gabbiani Giulio 
Published: February 2005

AbstractActin was localized in boar ejaculated spermatozoa by using specific antisera against cytoplasmic isoforms of actin [Otey et al., J Cell Biol, 102:1726–1737, 1986; Skalli et al., J Cell Biol, 103:2787–2796, 1986; Miller et al., Biochemistry, 26:6064–6070, 1987]. Indirect immunofluorescence and immunoelectron microscopy showed that γ and β actins were codistributed in the acrosomal and postacrosomal regions. Sperm actin was also identified on two‐dimensional gel as two spots in the isoelectric point and molecular weight corresponding to β and γ actins. Coelectrophoresis of sperm actin and chicken gizzard actin and immunoblots stained with the specific antibodies confirmed the presence of these two isoforms of actin.
Apparent densities of spermatozoa of various mammalian species
Authors: Oshio Shigeru 
Published: February 2005

AbstractThe apparent densities of sperm cells in several mammalian species were determined by means of Percoll density‐gradient centrifugation. Semen samples were obtained from (1) ejaculates from the bull, human, and rabbit, and (2) from the cauda epididymis of the goat, golden hamster, house musk shrew, mastomys, and mouse. The profiles of sperm distribution showed a single peak after the centrifugation in the first group and goat, whereas two separate main peaks in the second group (except goat). This disparity in sperm distribution profiles may be due mainly to differences in the degree of maturity of the sperm. Highly motile and mature sperm were obtained at higher densities, whereas immotile or immature sperm were found at the apparent densities.Thus, in mammals, the profiles of sperm distribution in the Percoll density gradient are classified into two types, those with a single peak and those with two separate peaks. The apparent density of sperm cells may be of importance in sperm physiology.
Classification, inhibition, and specificity studies of the vitelline coat lysin from toad sperm
Authors: Yamasaki Hisashi , Takamune Kazufumi , Katagiri Chiaki 
Published: February 2005

AbstractThe sonicated supernatant of the sperm of the toad, Bufo japonicus, can digest easily the vitelline coat (VC) of uterine eggs, and to a lesser extent the VC of coelomic eggs, but not that of activated eggs. The VC lysis and fertilization were competitively inhibited in the presence of t‐butyloxycarbonyl‐L‐Gln‐L‐Arg‐L‐Arg‐4‐methylcoumaryl‐7‐amide (Boc‐Gln‐Arg‐Arg‐MCA), suggesting the involvement of proteases in the fertilization process. Starting from a sonicated supernatant, a potent VC lysin, possessing hydrolytic activity on Boc‐Gln‐Arg‐Arg‐MCA, was obtained by anion‐exchange chromatography and gel filtration. The activity of the partially purified lysin was inhibited by diisopropyl fluorophosphate (DFP) and by such trypsin inhibitors as soybean trypsin inhibitor, leupeptin, and (p‐amidinophenyl) methanesulfonyl fluoride hydrochloride, but not by chymostatin, E‐64, and ethylene glycol bis(β‐aminoethyl ether)‐N,N,N′,N′‐tetraacetic acid. The molecular weight of the lysin was estimated to be 32K, based on the fluorographic image of 3H‐DFP binding to the lysin on sodium dodecyl sulfate gel electrophoresis. The VC lysin was most active at pH 7.0–7.6 and under low ionic strength equivalent to fresh water. The release of the VC lysin was induced upon incubation of sperm with the contents of oviducal pars recta granules (PRG), which are known to induce the acrosome reaction. We conclude that the protease studied here represents the VC lysin of toad sperm that is involved in fertilization by digesting the VC of uterine eggs, probably released as a result of the acrosome reaction induced by PRG.
Cytology of lepidoptera. III. Giant cysts: A morphological trait of apyrene spermatogenesis in an Ephestia kuehniella strain
Authors: Wolf Klaus Werner , Baumgart Kirsten , Traut Walther 
Published: February 2005

AbstractA comparative investigation of testicular eupyrene cysts (in larvae) and apyrene cysts (in pupae) of Ephestia kuehniella laboratory strains was conducted using light and electron microscopy. Eupyrene cysts in the first meiotic division contained 64 spermatocytes, which showed only moderate asynchrony. In one of the strains, a wild‐type strain, L, normal‐sized cysts occurred together with abnormally large cysts. These are called giant cysts in this article. One of the premeiotic cysts, early giant cysts, studied in detail, contained approximately a fourfold number of cells compared with the number in a eupyrene cyst of the same stage. In cysts harboring spermatocytes and spermatids, late giant cysts, cell differentiation was highly asynchronous.Failure in one of two control mechanisms in early cyst development may have caused the appearance of the cysts. Control of cell division might have been sloppy in apyrene spermatogonia. Hence, the spermatogonia within the cyst could have passed through additional division cycles. Alternatively, the giant cysts may have originated from more than one predefinitive gonial cell enclosed in a common envelope of sheath cells. As a third possibility, giant cysts could have arisen by fusion of normal cysts at a later stage. In either case, this is evidence that separation of eupyrene and apyrene pathways is earlier than was previously expected.In two other Ephestia strains, apyrene sperm development proceeded without formation of giant cysts. One was a mutant strain, a, and the other one was a recently established wild‐type strain, Sbr. Apyrene sperm development is considered an example of degenerate evolution in which enhanced variability between species and even between populations of one species is a common phenomenon.
Trout sertoli and leydig cells: Isolation, separation, and culture
Authors: Loir Maurice 
Published: February 2005

AbstractTrout testes at various stages of maturation were dissociated by perfusion at 12°C with collagenase plus pronase and then with collagenase alone, followed by slight shaking overnight in 1% bovine albumin. This step provided a suspension of isolated somatic and germ cells, clusters of interstitial cells, and either intact spermatogenetic cysts (meiotic testes) or clusters of Sertoli cells (other testes). Most of the spermatozoa were removed from the testis cell suspension by centrifugation in Percoll (density 1.065 g/ml). Sertoli and Leydig cells were prepared by a two‐step separation method: (1) the testis cell suspension was separated by sedimentation at unit gravity into “isolated cell” and “cell cluster” populations; (2) these populations were fractionated by isopyknic centrifugation in Percoll gradients. In terms of somatic cell composition, a nearly pure Sertoli cell (clusters) population was obtained between 1.017 and 1.033 g/ml and a Leydig cell (clusters) enriched population of between 1.033 and 1.048 g/ml (testes resuming spermatogenesis) or 1.048 and 1.062 g/ml (other testes).These various cell populations were cultured in modified Leibovitz L15 medium for 10–15 days. When seeded, the Sertoli cells had a normal ultrastructure that remained unchanged for at least 10 days, and the steroidogenic activity of Leydig cells could be stimulated by salmon gonadotropin. Leydig cells remained 3β‐HSD positive and produced progesterone and 17α, 20β‐OH progesterone for at least 11 days.This study points out that viable and differentiated trout somatic testicular cells can be prepared and cultured for several days.
Freezing and thawing alter chromatin stability of ejaculated human spermatozoa: Fluorescence acridine orange staining and Feulgen‐DNA cytophotometric studies
Authors: Royere D. , Hamamah S. , Nicolle J. C. , Barthelemy C. , Lansac J. 
Published: February 2005

AbstractCryopreservation and freezing‐thawing effects on the fertilizing ability of human spermatozoa commonly are evaluated by post‐thaw motility. Various studies have depicted the ultrastructural changes caused by freezing‐thawing, yet the chromatin alterations have been studied very limitedly. Our aim was to determine the extent to which freezing‐thawing alters the chromatin of human spermatozoa, using two analytical methods: acridine orange staining and Feulgen‐DNA cytophotometric studies. Both methods revealed a dramatic effect of freezing‐thawing on sperm chromatin: the native DNA content decreased as did the Feulgen‐DNA content, and sperm surface area was reduced. These results indicate an effect on DNA, diminished accessibility for Feulgen, and a decrease in nuclear surface area and prompt us to hypothesize a relationship between an “overcondensation” state for sperm chromatin after freezing‐thawing and a lower conception rate for human semen after cryostorage.
Zonae pellucidae of salt‐stored hamster and human eggs: Their penetrability by homologous and heterologous spermatozoa
Authors: Yoshimatsu Nobuhiro , Yanagimachi R. , Lopata Alex 
Published: February 2005

AbstractZonae pellucidae of unfertilized hamster and human eggs remain penetrable by homologous spermatozoa when they are stored in highly concentrated salt solutions [Yanagimachi et al., 1979]. Neutralization of salt solutions with the appropriate pH buffers is recommended for long‐term storage of the eggs (zonae), because zonae may gradually swell or even dissolve in acidic or alkaline solutions. At least for the hamster, 2 M ammonium sulfate solution containing 40 mM Hepes and 0.5% dextran (pH 7.0) seems to serve the purpose satisfactorily. Thorough rinsing of salt‐stored zonae prior to insemination is important, but inclusion of protease inhibitors in the rinsing medium does not appear to be essential. A dialysis method is recommended when a large number of salt‐stored eggs must be rinsed at one time. Salt‐stored hamster zonae, like fresh (control) zonae, permit attachment and penetration of hamster spermatozoa, but not human spermatozoa. Salt‐stored human zonae, on the other hand, allow penetration by not only human spermatozoa, but also hamster spermatozoa.
Does autocatalytic amplification of maturation‐promoting factor (MPF) exist in mammalian oocytes?
Authors: Fulka J. , Fléchon J.‐E. , Motlik J. , Fulka J. 
Published: February 2005

AbstractThe method of polyethylene‐glycol‐induced fusion of mammalian oocytes was applied to study maturation‐promoting factor (MPF) activity. After homologous fusions of one maturing–late diakinesis (LD), metaphase I (MI)–pig or mouse oocyte to one, two, or three immature–germinal vesicle (GV)–oocytes, giant cells were cultured in control or cycloheximide supplemented medium for 3 hours. The occurrence of germinal vesicle breakdown (GVBD) and premature chromosome condensation (PCC) served as a control of MPF activity. In giant cells composed of one maturing and one, two, or three immature oocytes, GVBD and PCC were observed in all cases after cultivation in the control medium. In the presence of cycloheximide, the completion of GVBD and PCC remained high when one maturing and one immature oocyte were fused (83.7% and 95.7% of GVBD in pig and mouse, respectively). However, in giant cells composed of one maturing and up to three immature oocytes, all GVs were broken down only occasionally (4.8% and 11.7% in pig and mouse, respectively). These results suggest that in pig and mouse oocytes MPF does not amplify autocatalytically, but requires active protein synthesis for its production.
Flow sorting of X and Y chromosome‐bearing mammalian sperm: Activation and pronuclear development of sorted bull, boar, and ram sperm microinjected into hamster oocytes
Authors: Johnson L. A. , Clarke R. N. 
Published: February 2005

AbstractFlow cytometric techniques were used to measure relative DNA content of X and Y chromosome‐bearing bull, boar, and ram sperm populations and to separate the two sex‐determining populations. Neat semen was prepared for flow cytometric analysis by washing, light sonication, and staining with 9 μM Hoechst 33342. Computer analysis of the bimodal histograms showed mean X‐Y DNA differences of 3.9, 3.7, and 4.2% for bull, boar, and ram, respectively. Flow cytometric reanalysis of sorted bull, boar, and ram sperm showed purities greater than 90%. Bull, boar, and ram sperm nuclei were microinjected into hamster oocytes. Microinjected sperm were either unsorted, sorted, unsorted plus dithio‐threitol (DTT) exposure, or sorted plus DTT exposure. Following microinjection, eggs were incubated 3 hr, fixed, and stained. A total of 579 eggs was observed for sperm activation (decondensation or formation of a male pronucleus). A lower percentage of sorted than unsorted (3 vs. 23%) boar sperm was activated (P <.05). However, sorted and unsorted DTT‐exposed boar sperm or sorted and unsorted bull or ram sperm, regardless of DTT treatment, did not differ significantly. Sorted sperm nuclei of both rams and bulls exhibited higher activation rates than sorted boar sperm (P <.05). Treatment of sperm with DTT increased the activation rate (P < .05) for sorted boar sperm but not for bull or ram sperm. These data represent the first separation of bull, boar, and ram X and Y chromosome‐bearing sperm populations and the first evidence that sperm of domestic animals sorted on the basis of DNA by flow cytometric procedures have the ability to decondense and to form pronuclei upon injection into a hamster egg.
New mutation causing sterility in the mouse
Authors: Handel M. A. , Lane P. W. , Schroeder A. C. , Davisson M. T. 
Published: February 2005

AbstractA new murine mutation, skeletal fusions with sterility, sks, has been identified. This mutation causes arrest during the pachytene stage of virtually all spermatogenic cells. Defects in chromosome pairing and appearance of the synaptonemal complex during meiosis in the male are apparent, but defective pairing is probably not the cause of sterility. Affected females are functionally infertile. Oocytes are capable of undergoing meiotic maturation in vitro but cannot be fertilized in vitro. Affected individuals of both sexes are characterized by fusions of vertebrae and of ribs. The sks gene has been mapped to Chromosome 4, 16.6 cM distal to the brown locus.
Oogenesis of the mayfly Habrophlebia eldae: Synthesis of vitelline and chorionic envelopes
Authors: Mazzini Massimo , Gaino Elda 
Published: February 2005

AbstractThe ultrastructure of developing ovarian follicles inside the panoistic ovarioles of Habrophlebia eldae were examined to observe the events occurring during egg maturation up to the full formation of the chorionic envelopes. The early vitellogenic follicles are coupled by gap junctions and are extensively interlocked with the oocyte plasma membrane via microvilli. With the onset of vitellogenesis, coated pits and coated vesicles are precursors to yolk deposition and are visible at the follicle cell‐oocyte interface. Postvitellogenic development entails the deposition of the egg envelopes. The vitelline envelope arises from the coalescence of rectangular plaques whose precursors are visible in Golgi complexes as heterogeneous electron‐opaque granules. A chorionic pattern of ridges on the egg surface characterizes the shell of H. eldae. The fully developed chorion shows three distinct regions with differently organized patterns. A fine layer of fibrous material (a secretion of the follicle cells, Ephemeroptera devoid of accessory glands) adheres to the egg chorion and is probably involved in attachment to the substrate.
Status of the rat acrosome during sperm‐zona pellucida interactions
Authors: Shalgi Ruth , Phillips David M. , Jones Roy 
Published: February 2005

AbstractOver the past 40 years evidence from many sources has indicated that the mammalian acrosome reaction occurs within or near the cumulus oophorus. Recently, however, workers investigating in vitro fertilization in the mouse have concluded that in this system the acrosome reaction takes place on the surface of the zona pellucida. We have investigated the interaction of rat spermatozoa and the zona pellucida by using the scanning electron microscope (SEM) and two monoclonal antibodies which are directed to antigens of the rat sperm acrosome.When in vitro inseminated eggs from which the cumulus has been removed are viewed with the SEM some sperm heads on the surface of the zona pellucida appear unaltered whereas others appear to be undergoing changes. In vivo, all displayed altered head morphology. Using immunogold labeling we found that the two antibodies employed, 2C4 and 5B1, were directed to acrosomal content and vesiculating acrosomal membranes. Immunofluoresence staining of zonae pellucidae in in vitro fertilization studies revealed numerous small positive regions. These were presumably acrosomal content and membranes which had been left on the zona surface by spermatozoa which had been associated with the zona surface. Our results suggest that the rat acrosome interacts with the zona pellucida. During this interaction some acrosomal content and membranes detach from the spermatozoon and remain on the surface of the zona pellucida.
Kinetics of spontaneous and induced acrosomal loss in human sperm incubated under capacitating and noncapacitating conditions
Authors: Byrd William , Tsu John , Wolf Don P. 
Published: February 2005

AbstractThe kinetics of spontaneous and induced acrosomal loss have been studied in human sperm incubated in capacitating and noncapacitating media. Acrosomal status was quantitated using indirect immunofluorescence with a monoclonal antibody. The response of sperm to induction by calcium ionophores was time dependent reaching a maximum after 6 hours of incubation under capacitating conditions. The inducible population slowly decreased in size through the balance of a 24‐hour incubation. The time‐dependent development of ionophore responsiveness by sperm exposed to capacitating conditions corroborates the idea that only capacitated cells can respond to undergo acrosomal loss in response to ionophore. In contrast, only a small, constant percentage of sperm incubated under noncapacitating conditions responded to ionophore. Substitution experiments involving the addition or deletion of human serum albumin suggest that albumin is not absolutely required for capacitation but is essential for the maintenance of motility. Polyvinyl alcohol can be substituted for serum albumin, but it does not support capacitation or motility as well as HSA. These studies may provide a basis for optimizing capacitating conditions for human sperm in vitro as well as for diagnosing fertility or fertility potential based on measurements of spontaneous and ionophore induced acrosomal loss under defined culture conditions.
In vitro capacitation and fertilizing ability of ejaculated rabbit sperm treated with lysophosphatidylcholine
Authors: Kim C. K. , Im K. S. , Zheng X. , Foote R. H. 
Published: February 2005

AbstractFour experiments were replicated 1) to establish dose‐response relationships between lysophosphatidylcholine (LPC), sperm motility, and the acrosome reaction (AR), 2) to evaluate the influence of rabbit serum (RS) on these endpoints, 3) to compare buck differences in induction of the AR, and 4) to examine fertilizing ability in vitro of sperm tested under the first three objectives. Semen was collected from Dutch‐belted rabbits, washed once by centrifugation, resuspended, and preincubated for 2 or 4 hr in a chemically defined medium (DM), DM plus 20% RS, or BSA‐free DM plus 20% RS at 37°C. At the end of preincubation LPC was added to the preincubated sperm at concentrations of from 0 to 100 μg/ml. Sperm were examined .5–4 hr later for AR and sperm motility. For in vitro fertilization, sperm and ova were coincubated in DM up to 24 hr after insemination and in a more complex medium for another 24 hr. Addition of LPC to 4‐hr‐preincubated sperm was more effective for inducing the AR than addition to 2‐hr‐preincubated sperm. A significant increase (P < .05) in the AR occurred in 15 and 30 min following exposure to 100 and 80 μg of LPC per ml, respectively, but the higher concentration of LPC decreased sperm motility. Addition of 20% RS to DM with or without BSA surprisingly inhibited the AR but maintained sperm motility, as expected. Bucks differed (P < .05) in the initial percentage and the induced percentage of AR sperm. For the AR the optimal concentration of LPC per ml was 80 μg, but for in vitro fertilization 60 μg tended to be superior.
Effects of transglutaminase substrates and inhibitors on the motility of demembranated reactivated spermatozoa
Authors: de Lamirande Eve , Gagnon Claude 
Published: February 2005

AbstractThe effects of transglutaminase (TGase) substrates putrescine, dansylcadaverine, spermine, etc., and the TGase inhibitor cystamine were tested on the motility of demembranated mammalian spermatozoa. These products blocked within a few seconds the motility of demembranated reactivated spermatozoa at concentrations ranging from 0.25 to 5 mM. These minimal inhibitory concentrations could be decreased 5–150‐fold when TGase substrates and inhibitor were incubated with demembranated spermatozoa for 15 min prior to the addition of Mg·ATP. The inhibition was reversed by higher concentrations of Mg·ATP but none of these TGase substrates or inhibitor could inhibit bull sperm dynein ATPase. TGase activities, as measured by the incorporation of 3H‐putrescine into TCA‐precipitable proteins, were present in both sperm Triton‐soluble and ‐insoluble fractions. On the other hand, amine acceptor protein substrates for the TGase‐catalyzed reaction were present only in the insoluble fraction. The Triton‐soluble TGase was similar to the known “tissue” TGases; the Triton‐insoluble TGase activity was calcium independent. The same TGase substrates and inhibitor that blocked the motility of reactivated spermatozoa also blocked TGase activities. Linear relationships were observed between the concentrations of these substances required to block sperm motility and those to block TGase activities. These data suggest the involvement of a TGase activity in sperm motility.