bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mucin‐like glycoproteins in the equine embryonic capsule
Authors: Oriol Julio G. , Betteridge K. J. , Clarke A. J. , Sharom F. J. 
Published: February 2005

AbstractThe equine embryonic capsule replaces the zona pellucida and envelops the conceptus during the second and third weeks of pregnancy. Although this capsule was described more than 100 years ago, its molecular structure has not been characterized. Here we present evidence that the glycoprotein(s) of the equine capsule resembles those of the mucin glycoprotein family. The resistance of the capsule to chemical and enzymatic solubilization was confirmed, and, as in mucins, protein constituted only 35–40% of its total dry mass. Determination of the sugar composition of the capsule using colorimetric assays and high‐performance anion‐exchange chromatography also showed it to have mucin‐like characteristics. Gal, GalNAc, sulfated sugars, and sialic acid make up a high proportion of the capsular carbohydrate, while GlcNAc, Glc, and Man are minor components. These findings were verified using lectin histochemical staining of frozen sections of conceptuses. The results of amino acid analysis were also consistent with the proposal that the capsular glycoproteins belong to the mucin family. Removal of the covalently bound carbohydrate by b̃‐elimination under reducing conditions demonstrated that the capsule is O‐glycosylated mainly on threonine residues. Affinity chromatography on jacalin‐agarose confirmed that, like mucins, the capsular glycoproteins are heavily O‐glycosylated. SDS‐PAGE analysis revealed a prominent 21‐kDa band, specific to the capsule, in preparations solubilized by trypsin but not by other proteases. Characterization of its constituent glycoprotein(s) should be helpful in elucidating the role of the capsule (and analogous blastocyst coverings in other species) during early pregnancy. © 1993 Wiley‐Liss, Inc.
The cleavage rate of digynic triploid mouse embryos during the preimplantation period
Authors: Henery C. C. , Kaufman M. H. 
Published: February 2005

AbstractTriploidy is a lethal condition in mammals, with most dying at some stage between implantation and term. In humans, however, a very small proportion of triploids are liveborn but display a wide range of congenital abnormalities. In particular, the placentas of human diandric triploid embryos consistently display “partial” hydatidiform molar degeneration, while those of digynic triploids generally do not show these histopathological features. In mice, the postimplantation development of diandric and digynic triploid embryos also differs. While both classes are capable of developing to the forelimb bud stage, no specific degenerative features of their placentas have been reported. Diandric triploid mouse embryos are morphologically normal while digynic triploid mouse embryos consistently display neural tube and occasionally cardiac abnormalities.Previously it was shown that the preimplantation development of micromanipulated diandric triploid mouse embryos was similar to developmentally matched diploid control embryos. In this study, the preimplantation development of micromanipulated digynic triploid mouse embryos is analysed and compared with that of diandric triploid mouse embryos in order to determine whether there is any difference in cleavage rate between these two classes of triploids.Standard micromanipulatory procedures were used to insert a female or a male pronucleus into a recipient diploid 1‐cell stage embryo. The karyoplast was fused to the cytoplasm of the embryo by electrofusion. These tripronucleate 1‐cell stage embryos were then transferred to pseudopregnant recipients and, at specific times after the HCG injection to induce ovulation, the embryos were recovered and total cell counts made. These results were plotted and regression lines drawn.An additional control group of embryos was subjected to similar micromanipulatory procedures to those used in the experimental study. These embryos had a single pronucleus removed and this was then reinserted into the perivitelline space. Diploidy was immediately restored by electrofusion. These embryos were transferred to recipients and at specific times after the HCG injection the embryos were recovered and total cell counts made. These results were also plotted and regression lines drawn.The results show that the cell doubling time of the digynic triploid embryos was 14.84 h (± 1.19). This was not significantly different from that of the diandric triploid embryos (13.55 h ± 0.86; P > 0.05) or of the manipulated diploid controls (12.12 h ± 0.79; P > 0.05). © 1993 Wiley‐Liss, Inc.
Incomplete development of human spermatozoa is associated with increased creatine phosphokinase concentration and abnormal head morphology
Authors: Huszar Gabor , Vigue Lynne 
Published: February 2005

AbstractOur previous creatine phosphokinase (CK) activity studies in human sperm revealed differences among men and among sperm populations within the same specimen. Samples with low sperm concentrations, high incidence of abnormal sperm morphology, and diminished fertility had higher per sperm CK activity. In the present work, we demonstrated, with 14C‐FDNB covalent CK active site modification and with direct CK immunocytochemistry, that the higher CK activity is related to an increased content of CK and of other proteins in sperm. Also, sperm heads with higher CK content were significantly larger and rounder and showed a higher incidence of amorph configuration. We suggest that these biochemical and morphological irregularities are related and are due to a failure of spermatogenesis, more specifically, to a higher retention of cytoplasm, which in normal sperm development is lost to the Sertoli cells as residual bodies. Thus higher CK activity and larger or irregular head size in human sperm signify cellular immaturity and a failure to complete spermatogenesis. © 1993 Wiley‐Liss, Inc.
Simultaneous detection of X‐ and Y‐bearing human sperm by double fluorescence in situ hybridization
Authors: Han Tie Lan , Ford Judith H. , Webb Graham C. , Flaherty Sean P. , Correll Anthony , Matthews Colin D. 
Published: February 2005

AbstractDouble fluorescence in situ hybridization (FISH) was used to detect sex chromosomes in decondensed human sperm nuclei. Biotinylated X chromosome specific (TRX) and digoxigenin‐labeled Y chromosome specific (HRY) probes were simultaneously hybridized to sperm preparations from 12 normal healthy donors. After the hybridization, the probes were detected immuno‐cytochemically, using two different and independent affinity systems. Ninety‐six percent of the 12,636 sperm showed fluorescent labeling, of which 47.4% were haploid X and 46.8% were haploid Y. A frequency of 0.46% of XX‐bearing sperm (0.28% disomic, 0.18% diploid) and 0.38% YY‐bearing sperm (0.21% disomic, 0.17% diploid) was found. The overall proportions of X‐ and Y‐bearing sperm in the ejaculates were 47.9% and 47.2%, respectively, which was not significantly different from the expected 50:50 ratio. In addition 0.21% of cells appeared to be haploid XY‐bearing sperm, 0.62% were diploid XY‐bearing cells, and 0.05% of cells were considered to be tetraploid cells. The application of double FISH to human sperm using X‐chro‐mosome and Y‐chromosome probes has allowed a more accurate assessment of the sex chromosal complements in sperm than single FISH method and quinacrine staining for Y‐bodies. © 1993 Wiley‐Liss, Inc.
Developmental ability of enucleated bovine oocytes matured in vitro after fusion with single blastomeres of eight‐cell embryos matured and fertilized in vitro
Authors: Mitani Tasuku , Utsumi Kyozo , Iritani Akira 
Published: February 2005

AbstractSingle blastomeres from eight‐cell stage bovine embryos matured and fertilized in vitro were electrically fused with enucleated oocytes matured in vitro. In experiment 1, The percentage of these reconstituted embryos developed to the two‐ to eight‐cell stage 48 hr after electrofusion was increased when both the eight‐cell embryos and the enucleated oocytes were derived from oocytes cultured with granulosa cells (14% vs. 38%). In experiment 2, the relationship between activation of oocytes and developmental ability of reconstituted embryos was examined. Although both ethanol and electrical stimulation efficiently induced parthenogenetic activation of oocytes matured in vitro for 26–28 hr (ethanol, 89%; electrical stimulation, 73%), the ratio of the second polarbody extrusion differed (80% vs. 22%). Ethanol‐treated enucleated oocytes, however, were not significantly different from the early cleavage of the reconstituted embryos 48 hr after electrofusion (nontreated, 38%; treated, 43%). In experiment 3, reconstituted embryos at the two‐ to eight‐cell stage 48 hr after the electrofusion were cocultured with granulosa cells for 6–7 days. Of 69 embryos, one developed to a morula and three developed to blastocysts. © 1993 Wiley‐Liss, Inc.
Transgenic strategies in reproductive endocrinology
Authors: Kelley Kevin M. , Johnson Thomas R. , Gwatkin Ralph B. L. , Ilan Judith , Ilan Joseph 
Published: February 2005

AbstractThe present discussion surveys some of the recently published studies utilizing transgenic strategies to address questions in reproductive endocrinology. Beginning with a brief introduction of the transgenic method itself, the following areas are covered: 1. Sexual development and Müllerian‐inhibiting substance; 2. Hypogonadal mice and hypothalamic GnRH; 3. The GnRH neuron: generation of immortalized rare cell types; 4. Glyco‐protein hormones: immortalized cells, development and evolution; 5. Growth hormone and reproduction; and, 6. Gestation and the insulin‐like growth factors. In each section, the discussion attempts to be integrative with respect to the significance of the results to physiological, cellular and molecular biology. We believe this approach is appropriate, as transgenic science itself is necessarily an integration of all of these levels of investigation and participation from those working at all levels is needed. © 1993 Wiley‐Liss, Inc.
Progressive expression of trophoblast‐specific genes during formation of mouse trophoblast giant cells in vitro
Authors: Carney E. W. , Prideaux V. , Lye S. J. , Rossant J. 
Published: February 2005

AbstractThe expression of a battery of trophoblast‐specific mRNAs was studied during trophectoderm development in vivo and in vitro to assess the use of these mRNAs as markers of trophoblast differentiation and to examine lineage relationships between various trophectoderm derivatives. In situ hybridization of sectioned day 6.5–18.5 mouse embryos localized mRNAs for mouse placental lactogens I and II and mouse proliferin (PLF) to trophoblast giant cells and proliferin‐related protein mRNA to the spongiotrophoblast and giant cell layers. A fifth marker, cDNA 4311, was found only in spongiotrophoblast. Day 3.5 blastocyst outgrowths and day 7.5 diploid extraembryonic ectoderm (EX) and ectoplacental cone (EPC) were then cultured to produce polyploid giant cells in vitro. Cultures were processed for in situ hybridization after 2, 4, or 6 days. EX and EPC both formed secondary giant cells, which expressed all markers in the same sequence as was observed in vivo, and primary giant cells in blastocyst outgrowths expressed the early giant cell markers PLF and PL‐I on days 4 and 6 of culture. EPC progressed through the sequence 2 days ahead of EX, indicating commitment of EPC to giant cell formation. These results suggest that EX, EPC, and primary and secondary giant cells all share in a common pathway of differentiation and that the highly ordered sequence of gene expression characteristic of this pathway occurs similarly in vivo and in vitro. © 1993 Wiley‐Liss, Inc.
Process of nuclear envelope reduction in spermiogenesis of a mosquito, Culex tigripes
Authors: Ndiaye Mady , Mattei Xavier 
Published: February 2005

AbstractWhen the Culex tigripes spermatid begins to elongate, the nucleus exhibits on its surface invaginations of the nuclear envelope. These invaginations have a uniform diameter of 0.3 μm. They separate from the envelope of the nucleus and form spherical intranuclear vesicles. In the old spermatids these vesicles are imprisoned in the condensed chromatin. The spermatozoon also possesses these vesicles which are then ovoid in shape. This process of vesiculation permits the diminution of the surface of the nucleus when it decreases in volume during spermiogenesis. © 1993 Wiley‐Liss, Inc.
Control of in vitro maturation of bovine cumulus‐oocyte complex by preovulatory granulosa cells
Authors: Rabahi Flora , Monniaux Danielle , Pisselet Claudine , Durand Philippe 
Published: February 2005

AbstractThe present study was designed to investigate (1) the influence of the secretions of follicular cells on the in vitro maturation of bovine cumulus‐oocyte complexes (COCs) and (2) the origin of the factors controlling the metabolic function of cumulus cells during the preovulatory period. Preovulatory granulosa cells were collected from synchronized heifers either before or 7–9 hr after the luteinizing hormone (LH) surge, and their secretions were recovered after a 3 hr incubation. Follicular fluids (FFs) originating from the same follicles and sera from the same animals were also collected. The effects of FFs, sera, and secretions of granulosa cells on COC metabolism were compared during 24 hr of culture. FF stimulated cumulus expansion, progesterone secretion, and overall protein synthesis by COCs but decreased the amount of a major protein of 28 kDa. The time at which FF was collected influenced both cumulus expansion and protein synthesis by COCs. The effects of FF on COC metabolism were detected at the lowest protein concentration studied (0.073 mg/ml) and could be mimicked with serum, but only at a protein concentration 100‐fold higher. The inhibitory effect of FF and serum on the amount of the 28 kDa protein was reproduced with the secretions of granulosa cells, acting at protein concentrations five‐ and 500‐fold lower, respectively. However, the secretions of granulosa cells enhanced slightly cumulus expansion and had no effect on progesterone secretion and overall protein synthesis by COCs. These results suggest that COC metabolism is influenced both by endocrine and by local factors secreted by granulosa cells in response to gonadotropins. The paracrine control of COC metabolism by preovulatory granulosa cells could be exerted not only via intercellular contacts but also via substances secreted in FF. © 1993 Wiley‐Liss, Inc.
Phosphorylcholine‐binding proteins from the seminal fluids of different species share antigenic determinants with the major proteins of bovine seminal plasma
Authors: Leblond E. , Desnoyers L. , Manjunath P. 
Published: February 2005

AbstractThe major proteins of bovine seminal plasma, BSP‐A1, BSP‐A2, BSP‐A3, and BSP‐30kDa (collectively named BSP proteins) bind to phospholipids containing the phosphorylcholine moiety. An affinity purification method using a p‐aminophenyl phosphorylcholine‐Agarose (PPC‐Agarose) affinity matrix was developed for their purification. In this study, we investigated the distribution of BSP‐like analogues in seminal fluid of the human, porcine, hamster, mouse, and rat using this affinity matrix. Alcohol precipitates of the seminal plasma/seminal vesicle secretions (SP/SVS) were further delipidated using isopropyl ether:n‐butanol (60:40). The protein preparations obtained were solubilized in a minimal volume of buffer A (50 mM Tris‐HCl, pH 7.4, 150 mM NaCl, 5 mM EDTA, 0.02% NaN3), dialyzed against the same buffer, and applied to a PPC‐Agarose column connected to a FPLC system. The unbound material was washed out and the adsorbed proteins eluted with buffer A containing 10 mM phosphorylcholine (PrC) and 10 M urea. The fractions were separated by SDS‐PAGE, stained or transferred onto a nitrocellulose membrane, and probed with rabbit polyclonal anti‐BSP antibodies. Anti‐BSP cross‐reacting proteins were detected in the seminal fluids of all the species investigated. Moreover, many of these proteins bound to the affinity matrix. The BSP proteins and their immunoreacting analogues appear to be ubiquitous in mammals and may possibly be involved in a common function such as in the modification of the lipid content of the sperm plasma membrane. © 1993 Wiley‐Liss, Inc.
Effects of polyamine biosynthesis inhibitors on the progesterone‐initiated increase in intracellular free Ca2+ and acrosome reactions in human sperm
Authors: Meizel Stanley , Turner K. O. 
Published: February 2005

AbstractThis laboratory has previously reported that progesterone can initiate a rapid transient increase in the concentration of intracellular free Ca2+([Ca2+]i) and an increase in a Ca2+‐requiring exocytotic event, the acrosome reaction (AR) in human sperm. Rapid increases in Ca2+ fluxes of some mammalian cells caused by another steroid, testosterone, require polyamine biosynthesis. Herein, we tested two polyamine biosynthesis suicide inhibitors for their effects on the progesterone‐initiated increase in [Ca2+]i and AR in capacitated human sperm in vitro: DL‐α‐(difluoromethyl)ornithine hydrochloride (DFMO), an inhibitor of putrescine synthesis by ornithine decarboxylase and (5′‐{[(Z))‐4‐amino‐2‐butenyl]methylamino}‐5′‐deoxyadenosine (MDL 73811), an inhibitor of S‐adenosylmethionine decarboxylase (required for spermidine and spermine synthesis). Sperm were capacitated in vitro and preincubated 10 min with 4.9 mM DFMO or 9.8 μM MDL 73811 with or without various polyamines (245 μM). Progesterone (3.09 μM final concentration) or progesterone solvent (ethanol, 0.1% final concentration) was then added, sperm fixed 1 min after additions and AR assayed by indirect immunofluorescence or with fluorescein‐labeled Con A lectin. DFMO strongly inhibited the AR but putrescine (product of ornithine decarboxylase and precursor of spermidine and spermine) reversed that inhibition. Preincubation for 25 min with DMFO + spermidine also reversed DFMO inhibition. MDL 73811 inhibited the progesterone‐initiated AR, and a 10 min preincubation with spermidine, but not putrescine or spermine, reversed that inhibition. Preincubations with putrescine alone or with spermidine alone followed by addition of the progesterone solvent did not initiate the AR, and such preincubations followed by progesterone addition did not increase the AR more than progesterone alone. MDL 73811 and DFMO partially inhibited the rapid progesterone‐initiated increase in [Ca2+]i (assayed with fura‐2), and those inhibitions were partially reversed by putrescine and spermidine, respectively. Putrescine or spermidine alone did not increase [Ca2+]i nor did preincubation with either polyamine followed by progesterone addition increase [Ca2+]i more than progesterone alone. Neither inhibitor was able to inhibit the AR initiated by the calcium ionophore, ionomycin. Our results suggest that human sperm polyamine biosynthesis is necessary for the progesterone‐initiated rapid increase in [Ca2+]i and subsequent membrane events of the AR. © 1993 Wiley‐Liss, Inc.
PCR sexing and developmental rate differences in preimplantation mouse embryos fertilized and cultured in vitro
Authors: Valdivia Ruby P. A. , Kunieda Tetsuo , Azuma Sadahiro , Toyoda Yutaka 
Published: February 2005

AbstractA two‐step polymerase chain reaction (PCR) assay was used to determine the sex of mouse preimplantation embryos obtained from oocytes fertilized and cultured in vitro, to investigate the differences in the developmental rates of mouse embryos according to the sex. All the in vitro developed embryos could be analyzed by this method. When the embryos were classified according to the time of morula to blastocyst transition as fast‐intermediate‐ and slow‐growing embryos, a significantly high percentage (78.0%) of the fast‐developing embryos were identified as males; while a significantly lower percentage (42.5%) of slow‐developing embryos were identified as males. The intermediate‐developing embryos presented a sex ratio not significantly different from the total (57.5%). The deviation of sex ratio was further confirmed by embryo transfer experiment, where fast‐ and slow‐developing embryos gave 76.2% and 25.7% male fetuses, respectively. We concluded that male mouse embryos fertilized and cultured in vitro develop faster than female embryos. © 1993 Wiley‐Liss, Inc.
High frequency of DNA ploidy abnormalities in preimplantation embryos of the rabbit
Authors: Schumacher Armin , Fischer Bernd , Agorastos Theodoros , Beier Henning M. 
Published: February 2005

AbstractThe DNA ploidy of Feulgen‐stained cell nuclei of in vivo preimplantation rabbit embryos was assayed by cytophotometry. DNA ploidy abnormalities were detected in single‐cell nuclei readings by the criterion of ≥5C DNA. These hypermodal DNA contents are referred as to DNA aneuploidy. Two, 4 and 6 days old rabbit embryos, all of normal gross morphology, were investigated.The incidence of embryos with DNA ploidy abnormalities increased from 17% in 2‐day‐old cleavage stages to 51% in 6‐day‐old expanded blastocysts. All these embryos were mosaics and the percentage of DNA aneuploid nuclei per embryo did not usually exceed 9%. Fifteen percent of the expanded blastocysts, however, contained up to 23% abnormal nuclei. Throughout the embryonic stages studied, the DNA content of abnormal nuclei was remarkably constant and averaged 5.8C. DNA aneuploid and euploid blastocysts did not differ in size. A maternal FSH treatment did not influence the DNA ploidy.This is the first report on the DNA ploidy pattern in preimplantation rabbit embryos. Our results indicate that DNA aneuploidy of single blastomeres is common in this species and occurs more often than generally assumed. The embryonic viability does not seem to be affected by the presence of DNA aneuploid blastomeres supporting earlier findings that a limited number of abnormal blastomeres is compatible with normal preimplantation development. © 1993 Wiley‐Liss, Inc.
Sites of transcription of the Müllerian inhibiting substance gene in mouse testis
Authors: Ao Asangla , Erickson Robert P. , Stalvey John R. D. 
Published: February 2005

AbstractWe have examined the transcription of Müllerian inhibiting substance (MIS) in testis by the sensitive technique of reverse transcription polymerase chain reaction (RTPCR). A developmental study of testis by this nonquantitative technique showed expression at all postnatal stages, including adults while liver and kidney provided negative controls. Cell separation studies indicated that highly purified interstitial cells, as well as less homogeneous Sertoli cell‐enriched and germ cell‐enriched fractions, contained RNA for MIS. The transcription of MIS in an interstitial cell type was confirmed by finding MIS mRNA in purified Leydig cells. Inasmuch as the germ cell‐enriched fraction contains some Sertoli cells, and XX,Sxra and XX,Sxrb which have germ cell‐depleted testes, contain MIS mRNA, a Sertoli cell source remains likely for the seminiferous tubule compartment. © 1993 Wiley‐Liss, Inc.