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Full-Text Articles in Medicine and Health Sciences
The Gamma-Subunit Of The Na-K-Atpase As A Potential Regulator Of Apical And Basolateral Na+-Pump Isozymes During Development Of Bovine Pre-Attachment Embryos., L C Barcroft, S E Gill, A J Watson
The Gamma-Subunit Of The Na-K-Atpase As A Potential Regulator Of Apical And Basolateral Na+-Pump Isozymes During Development Of Bovine Pre-Attachment Embryos., L C Barcroft, S E Gill, A J Watson
Obstetrics & Gynaecology Publications
Expression and activity of the Na-K-ATPase within the basolateral membrane domains of the trophectoderm epithelium provide the driving force for accumulation of Na(+) and Cl(-) across the nascent epithelium, mediating fluid movement into the forming blastocoel. Within the trophectoderm of the bovine blastocyst, multiple isozymes of the Na-K-ATPase are expressed. Immunolocalization has demonstrated that the alpha1-isozyme localizes within the basolateral membrane, whereas the alpha 3-isozyme localizes to the apical cell margins. Gene-specific RT-PCR and wholemount indirect immunofluorescence confocal laser scanning microscopy were used to examine expression of the Na-K-ATPase gamma-subunit (a regulatory subunit of the Na-K-ATPase) throughout development of bovine …
Sensitivity Of Bovine Blastocyst Gene Expression Patterns To Culture Environments Assessed By Differential Display Rt-Pcr., D R Natale, P A De Sousa, M E Westhusin, A J Watson
Sensitivity Of Bovine Blastocyst Gene Expression Patterns To Culture Environments Assessed By Differential Display Rt-Pcr., D R Natale, P A De Sousa, M E Westhusin, A J Watson
Obstetrics & Gynaecology Publications
The use of culture media to support the development of preimplantation embryos to the blastocyst stage is often associated with detrimental effects on normal development. These effects have been uncovered largely by investigating the phenotypic abnormalities displayed by fetuses and newborns derived from cultured preimplantation embryos. Research to understand the impact of culture on the embryonic developmental programme has focused on embryo metabolism, gene expression and genomic imprinting. We have used differential display RT-PCR to examine culture influences on global transcript pools in bovine embryos. Others have examined culture influences on candidate "marker genes" in cultured murine, ovine and bovine …
Cyclooxygenase-2 And Prostaglandin E(2)(Pge(2)) Receptor Messenger Rnas Are Affected By Bovine Oocyte Maturation Time And Cumulus-Oocyte Complex Quality, And Pge(2) Induces Moderate Expansion Of The Bovine Cumulus In Vitro., M D Calder, A N Caveney, M E Westhusin, A J Watson
Cyclooxygenase-2 And Prostaglandin E(2)(Pge(2)) Receptor Messenger Rnas Are Affected By Bovine Oocyte Maturation Time And Cumulus-Oocyte Complex Quality, And Pge(2) Induces Moderate Expansion Of The Bovine Cumulus In Vitro., M D Calder, A N Caveney, M E Westhusin, A J Watson
Obstetrics & Gynaecology Publications
Expression of cyclooxygenase-2 (COX-2) and prostaglandin E(2) (PGE(2)) receptor 2 (EP2) are necessary for rodent cumulus expansion in vivo. Prostaglandin E(2) receptor 3 (EP3) has been detected in bovine preovulatory follicles and corpora lutea. The current experiments examined the effect of PGE(2) on bovine cumulus expansion in vitro and expression of COX-2, EP1, EP2, EP3, and EP4 mRNAs in bovine cumulus-oocyte complexes (COCs) at 0, 6, 12, 18, and 24 h time points during maturation in vitro. Concentrations of PGE(2) above 50 ng/ml resulted in moderate cumulus expansion of bovine COCs, but expansion did not occur in the absence of …
Amino Acid Concentrations In Fluids From The Bovine Oviduct And Uterus And In Ksom-Based Culture Media., Y M Elhassan, G Wu, A C Leanez, R J Tasca, A J Watson, M E Westhusin
Amino Acid Concentrations In Fluids From The Bovine Oviduct And Uterus And In Ksom-Based Culture Media., Y M Elhassan, G Wu, A C Leanez, R J Tasca, A J Watson, M E Westhusin
Obstetrics & Gynaecology Publications
Amino acids in bovine oviductal and uterine fluids were measured and compared with those in modified simplex optimized medium (KSOM) supplemented with either fetal calf serum or Minimum Essential Medium amino acids in addition to bovine serum albumin, fetal calf serum or polyvinyl alcohol. Concentrations of cysteine, threonine, tryptophan, alanine, aspartate, glycine, glutamate, proline, beta-alanine, and citrulline were higher in oviductal fluids than in KSOM-based culture media. Nonessential and essential amino acids were present in ratios of 5:1 and 2:1 in oviductal and uterine fluids, respectively. Concentrations of alanine (3.7 mM), glycine (14.1 mM) and glutamate (5.5 mM) were high …
Expression Of Pthrp And Pthr (Pth/Pthrp-R) Mrnas And Polypeptides In Bovine Ovary And Stimulation Of Bovine Blastocyst Development In Vitro Following Pthrp Treatment During Oocyte Maturation., P H Watson, M E Westhusin, A J Watson
Expression Of Pthrp And Pthr (Pth/Pthrp-R) Mrnas And Polypeptides In Bovine Ovary And Stimulation Of Bovine Blastocyst Development In Vitro Following Pthrp Treatment During Oocyte Maturation., P H Watson, M E Westhusin, A J Watson
Obstetrics & Gynaecology Publications
Parathyroid hormone related protein (PTHrP) and its receptor have well-established roles in the development and regulation of many tissues, including bone and mammary gland. The objectives of this study were: (1) to characterize the distribution of mRNAs encoding parathyroid hormone (PTH)-related protein (PTHrP) and receptor (PTHR) in bovine ovary; (2) to characterize the distribution of PTHrP and PTHR polypeptides in bovine ovary; (3) to examine the influences of PTHrP (1-141) treatment during bovine oocyte maturation in vitro on blastocyst development. mRNAs encoding PTHrP and PTHR were detected by in situ hybridization methods in oocytes, and granulosa cells in all follicles …
Mrnas Encoding Aquaporins Are Present During Murine Preimplantation Development., H Offenberg, L C Barcroft, A Caveney, D Viuff, P D Thomsen, A J Watson
Mrnas Encoding Aquaporins Are Present During Murine Preimplantation Development., H Offenberg, L C Barcroft, A Caveney, D Viuff, P D Thomsen, A J Watson
Obstetrics & Gynaecology Publications
The present study was conducted to investigate the mechanisms underlying fluid movement across the trophectoderm during blastocyst formation by determining whether aquaporins (AQPs) are expressed during early mammalian development. AQPs belong to a family of major intrinsic membrane proteins and function as molecular water channels that allow water to flow rapidly across plasma membranes in the direction of osmotic gradients. Ten different AQPs have been identified to date. Murine preimplantation stage embryos were flushed from the oviducts and uteri of superovulated CD1 mice. Reverse transcription-polymerase chain reaction (RT-PCR) methods employing primer sets designed to amplify conserved sequences of AQPs (1-9) …
Differential Involvement Of Na(+),K(+)-Atpase Isozymes In Preimplantation Development Of The Mouse., D J Macphee, D H Jones, K J Barr, D H Betts, A J Watson, G M Kidder
Differential Involvement Of Na(+),K(+)-Atpase Isozymes In Preimplantation Development Of The Mouse., D J Macphee, D H Jones, K J Barr, D H Betts, A J Watson, G M Kidder
Obstetrics & Gynaecology Publications
Na(+),K(+)-ATPase plays an essential role in mammalian blastocoel formation (cavitation) by driving trans-epithelial sodium transport. Previously, the alpha1 and beta1 subunit isoforms of this enzyme were identified in preimplantation mouse embryos and were assumed to be responsible for this function. Here we show that mRNAs encoding an additional alpha subunit isoform (alpha3) and the remaining two beta subunit isoforms are also present in preimplantation embryos. Whereas alpha3 mRNA accumulates between the four-cell and the blastocyst stages and thus results from embryonic transcription, the same could not be demonstrated for beta2 and beta3 mRNAs. Immunoblot analyses confirmed that these subunits are …
Impact Of Bovine Oocyte Maturation Media On Oocyte Transcript Levels, Blastocyst Development, Cell Number, And Apoptosis., A J Watson, P De Sousa, A Caveney, L C Barcroft, D Natale, J Urquhart, M E Westhusin
Impact Of Bovine Oocyte Maturation Media On Oocyte Transcript Levels, Blastocyst Development, Cell Number, And Apoptosis., A J Watson, P De Sousa, A Caveney, L C Barcroft, D Natale, J Urquhart, M E Westhusin
Obstetrics & Gynaecology Publications
The objectives were 1) to investigate the effects of oocyte maturation in serum-free and amino acid-supplemented defined media on oocyte transcript levels, blastocyst cell number, and apoptosis; 2) to investigate the influence of oocyte maturation culture atmosphere on blastocyst development, total cell number, and apoptosis; and 3) to examine the influence of epidermal growth factor (EGF) during oocyte maturation on blastocyst cell number and apoptosis. The results demonstrate that blastocysts derived from in vitro maturation, fertilization, and embryo culture protocols undergo apoptosis but that apoptotic levels are not greatly influenced by the oocyte maturation environment. Amino acid supplementation of oocyte …
Effects Of Superovulated Heifer Diet Type And Quantity On Relative Mrna Abundances And Pyruvate Metabolism In Recovered Embryos., C Wrenzycki, P De Sousa, E W Overström, R T Duby, D Herrmann, A J Watson, H Niemann, D O'Callaghan, M P Boland
Effects Of Superovulated Heifer Diet Type And Quantity On Relative Mrna Abundances And Pyruvate Metabolism In Recovered Embryos., C Wrenzycki, P De Sousa, E W Overström, R T Duby, D Herrmann, A J Watson, H Niemann, D O'Callaghan, M P Boland
Obstetrics & Gynaecology Publications
This study investigated the effects of quantity and type of diet fed to superovulated donor heifers on molecular and metabolic indices of embryonic development. These effects included the relative abundances of mRNAs for the alpha 1 subunit of Na/K-ATPase and the antioxidant enzyme Cu/Zn-SOD, as well as pyruvate utilization in bovine morulae and blastocysts developed in vivo. Heifers were fed a daily ration of either grass silage and a citrus-beet pulp-based concentrate or grass silage and a barley-based concentrate for 116 days, both at 3 kg per day or ad libitum. In embryos derived from heifers fed the pulp-based diets, …
Igf Paracrine And Autocrine Interactions Between Conceptus And Oviduct., A J Watson, M E Westhusin, Q A Winger
Igf Paracrine And Autocrine Interactions Between Conceptus And Oviduct., A J Watson, M E Westhusin, Q A Winger
Obstetrics & Gynaecology Publications
Development in vitro is influenced by embryo density, serum, somatic cell co-culture and the production of 'embryotrophic' paracrine and autocrine factors. Research in our laboratory has focussed principally on the insulin-like growth factor (IGF) family. We have demonstrated that pre-attachment bovine and ovine embryos express mRNAs encoding a number of growth factor ligand and receptor genes including all members of the IGF ligand and receptor family throughout this developmental interval. In addition, early embryos express mRNAs encoding IGF-binding proteins (IGFBPs) 2-5 from the one-cell to the blastocyst stage and IGFBP5 mRNA at the blastocyst stage. Cultured bovine blastocysts release up …
Transient Expression Of A Translation Initiation Factor Is Conservatively Associated With Embryonic Gene Activation In Murine And Bovine Embryos., P A De Sousa, A J Watson, R M Schultz
Transient Expression Of A Translation Initiation Factor Is Conservatively Associated With Embryonic Gene Activation In Murine And Bovine Embryos., P A De Sousa, A J Watson, R M Schultz
Obstetrics & Gynaecology Publications
In the present study the abundance of mRNAs for eukaryotic translation initiation factors eIF-1A (formerly known as eIF-4C), -2alpha, -4A, -4E, and -5 was examined in in vivo-derived mouse embryos throughout preimplantation development using a semiquantitative reverse transcription-polymerase chain reaction assay. Although the mRNA profile for each gene is unique, only mRNA for eIF-1A transiently increases during embryonic gene activation (EGA) at the 2-cell stage, and this was confirmed by an independent hybridization-based assay. In in vitro-developed bovine embryos, mRNA for eIF-1A was transiently detected at the 8-cell stage, when the major activation of the genome occurs in this species. …
Na/K-Atpase-Mediated 86rb+ Uptake And Asymmetrical Trophectoderm Localization Of Alpha1 And Alpha3 Na/K-Atpase Isoforms During Bovine Preattachment Development., D H Betts, L C Barcroft, A J Watson
Na/K-Atpase-Mediated 86rb+ Uptake And Asymmetrical Trophectoderm Localization Of Alpha1 And Alpha3 Na/K-Atpase Isoforms During Bovine Preattachment Development., D H Betts, L C Barcroft, A J Watson
Obstetrics & Gynaecology Publications
This study evaluated Na/K-ATPase alpha 1- and alpha 3-subunit isoform polypeptide expression and localization during bovine preattachment development. Na/K-ATPase cation transport activity from the one-cell to blastocyst stage was also determined by measuring ouabain-sensitive 86Rb+ uptake. Both alpha1- and alpha 3-subunit polypeptides were detected by immunofluorescence to encircle the entire cell margins of each blastomere of inseminated zygotes, cleavage stage embryos, and morulae. Immunofluorescent localization of alpha1-subunit polypeptide in bovine blastocysts revealed an alpha1 immunofluorescence signal confined to the basolateral membrane margins of the trophectoderm and encircling the cell periphery of each inner cell mass (ICM) cell. In contrast, alpha …
Bovine Oviductal And Embryonic Insulin-Like Growth Factor Binding Proteins: Possible Regulators Of "Embryotrophic" Insulin-Like Growth Factor Circuits., Q A Winger, P De Los Rios, V K Han, D T Armstrong, D J Hill, A J Watson
Bovine Oviductal And Embryonic Insulin-Like Growth Factor Binding Proteins: Possible Regulators Of "Embryotrophic" Insulin-Like Growth Factor Circuits., Q A Winger, P De Los Rios, V K Han, D T Armstrong, D J Hill, A J Watson
Obstetrics & Gynaecology Publications
Bovine oviductal monolayer and vesicle primary cultures express insulin-like growth factor (IGF)-I and -II mRNAs and polypeptides. Early bovine embryos also express IGF-I, IGF-II, IGF-I receptor, IGF-II receptor, and insulin receptor mRNAs. This study reports the expression of IGF binding protein (IGFBP) mRNAs and polypeptides in bovine oviduct primary cultures and IGFBP mRNAs in preattachment embryos. Release of immunoreactive IGF-I and IGF-II by oviduct cultures and bovine blastocysts was also determined. IGFBP-2, -3, -4, and -5 transcripts were observed in oviduct primary cultures throughout an 8-day interval. IGFBP-1 and -6 mRNAs were consistently not detected in the oviduct. Messenger RNAs …
Expression Of Genes Encoding Antioxidant Enzymes In Preimplantation Mouse And Cow Embryos And Primary Bovine Oviduct Cultures Employed For Embryo Coculture., M B Harvey, M Y Arcellana-Panlilio, X Zhang, G A Schultz, A J Watson
Expression Of Genes Encoding Antioxidant Enzymes In Preimplantation Mouse And Cow Embryos And Primary Bovine Oviduct Cultures Employed For Embryo Coculture., M B Harvey, M Y Arcellana-Panlilio, X Zhang, G A Schultz, A J Watson
Obstetrics & Gynaecology Publications
Preimplantation embryos from a variety of mammalian species contrast markedly in their response to culture in vitro. Murine preimplantation embryos display a wider tolerance than other mammalian species to culture environments, and this has contributed to the development of several effective defined culture media. Embryo coculture on somatic cells remains the most effective method of supporting reasonable rates of bovine preimplantation development in vitro. The patterns of gene expression for several antioxidant enzymes during preimplantation murine and bovine development were examined by use of the reverse transcription-polymerase chain reaction technique to determine whether the differential developmental capacity of mammalian preimplantation …
A Growth Factor Phenotype Map For Ovine Preimplantation Development., A J Watson, P H Watson, M Arcellana-Panlilio, D Warnes, S K Walker, G A Schultz, D T Armstrong, R F Seamark
A Growth Factor Phenotype Map For Ovine Preimplantation Development., A J Watson, P H Watson, M Arcellana-Panlilio, D Warnes, S K Walker, G A Schultz, D T Armstrong, R F Seamark
Obstetrics & Gynaecology Publications
The reverse transcription-polymerase chain reaction (RT-PCR) was used to determine the patterns of expression for several growth factor ligand and receptor genes during ovine preimplantation development. Transcripts for insulin-like growth factor (IGF)-I, IGF-II, and the receptors for insulin and IGF-I were detected throughout ovine preimplantation development from the 1-cell to the blastocyst stage. Transforming growth factor alpha (TGF alpha) transcripts were also detected throughout ovine preimplantation development. The mRNAs encoding basic fibroblast growth factor (bFGF) were detected in all stages of the ovine preimplantation embryo, although the relative abundance of this transcript consistently decreased from the 1-cell to the blastocyst …
Preimplantation Development Of In Vitro-Matured And In Vitro-Fertilized Ovine Zygotes: Comparison Between Coculture On Oviduct Epithelial Cell Monolayers And Culture Under Low Oxygen Atmosphere., A J Watson, P H Watson, D Warnes, S K Walker, D T Armstrong, R F Seamark
Preimplantation Development Of In Vitro-Matured And In Vitro-Fertilized Ovine Zygotes: Comparison Between Coculture On Oviduct Epithelial Cell Monolayers And Culture Under Low Oxygen Atmosphere., A J Watson, P H Watson, D Warnes, S K Walker, D T Armstrong, R F Seamark
Obstetrics & Gynaecology Publications
The roles of medium composition, serum source, embryo coculture, and culture under low O2 conditions on the development of in vitro-matured and in vitro-fertilized (IVMF) ovine zygotes were investigated in three separate experiments. In the first experiment, the proportion of cocultured IVMF zygotes developing to the blastocyst stage was significantly higher (38.0% vs. 3.5%; p < 0.05) than that of non-cocultured zygotes treated within three embryo culture media (TCM-199 + 10% fetal bovine serum [FBS]; bicarbonate-buffered, glucose-free synthetic oviduct fluid medium [mod-SOFM] + 10% FBS; and bicarbonate-buffered BSA-free Tyrode's salt solution [mod-TALP] + 10% FBS) under a 5% CO2 atmosphere in air. In a second experiment, a significantly higher (p < 0.05) proportion of cocultured zygotes placed in TCM-199 medium survived to the blastocyst stage (37.4% blastocysts vs. 23.4% in mod-SOFM). No significant effect of serum (FBS vs. human serum [HS]) was observed on embryonic development, but coculture was confirmed to exert a significant influence on development to the blastocyst stage. In the final experiment, survival of the embryo under a reduced oxygen (5% CO2:5% O2:90% N2) atmosphere was investigated. In contrast to results in the initial experiments, embryonic survival was significantly higher (p < 0.05) in the non-cocultured treatment groups (21.9% blastocysts vs. 0.4% for cocultured zygotes). Serum source also had a significant (p < 0.05) influence upon the development of non-cocultured zygotes: 32.3% of zygotes cultured with HS progressed to the blastocyst stage vs. 11.5% of zygotes cultured in FBS-supplemented medium. These results have characterized two distinct culture environments, each capable of supporting the development of high frequencies of unselected IVMF zygotes to the blastocyst stage in vitro.
Possible Roles Of Insulin And Insulin-Like Growth Factors In Rat Preimplantation Development: Investigation Of Gene Expression By Reverse Transcription-Polymerase Chain Reaction., X Zhang, G M Kidder, A J Watson, G A Schultz, D T Armstrong
Possible Roles Of Insulin And Insulin-Like Growth Factors In Rat Preimplantation Development: Investigation Of Gene Expression By Reverse Transcription-Polymerase Chain Reaction., X Zhang, G M Kidder, A J Watson, G A Schultz, D T Armstrong
Obstetrics & Gynaecology Publications
The sensitive mRNA phenotyping technique of reverse transcription-polymerase chain reaction was used to demonstrate that insulin receptor mRNA is present in rat embryos during the preimplantation period. In addition, mRNA encoding insulin-like growth factor (IGF) type I and type II receptors have also been detected in rat preimplantation embryos. IGF-I mRNA was not detected in preimplantation embryos but was found in oviducts and uteri of prepubertal and early pregnant rats. IGF-II mRNA was present in both embryos and in oviducts and uteri during the preimplantation period. These findings suggest that insulin and IGF-I could influence early embryo development in endocrine …
How To Make A Blastocyst., A J Watson, G M Kidder, G A Schultz
How To Make A Blastocyst., A J Watson, G M Kidder, G A Schultz
Obstetrics & Gynaecology Publications
Several of the new reproductive technologies have been cultivated from our current understanding of the genetic programming and cellular processes that are involved in the major morphogenetic events of mammalian preimplantation development. Research directed at characterizing the patterns of gene expression during early development has shown that the embryo is initially under maternal control and later superseded by new transcriptional activity provided by the activation of the embryonic genome. Several embryonic transcripts encoding: (i) growth factors, (ii) cell junctions, (iii) plasma membrane ion transporters, and (iv) cell adhesion molecules have been identified as contributing directly to the progression of the …