Search Results
Results 201 - 250 of 1207
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Chenoweth P J - - 2007
Early pregnancy failure or loss (EPL) represents a major source of wastage and inefficiency in livestock production systems. Although successful embryo development is dependent upon genetic and epigenetic contributions from both the male and female, potential adverse male affects on embryo quality and development are probably often underestimated. Of adverse ...
Isom S Clay - - 2007
Decades worth of research have consistently shown the adverse effects of elevated temperatures on reproductive parameters of livestock species. The objective of this study was to evaluate the developmental and apoptotic responses of porcine in vitro fertilized (IVF) and parthenogenetically activated (PA) embryos heat stressed at the late 1-cell stage. ...
Brooke D A - - 2007
Superovulation is a fundamental procedure for generating transgenic rodents. While various methods exist, zygote yield/quality remain suboptimal, making these techniques open to refinement. All require a follicle stimulating and a luteinising effect. The former can be induced by pregnant mare serum gonadotrophin (PMSG) or other compounds like human menopausal gonadotrophin ...
de Lacey Sheryl - - 2007
BACKGROUND: In the final decision for the disposition of unused IVF embryos patients must choose between options involving either donation or destruction, and this decision must be made in a context where there is tension about the status of embryos (i.e. whether viewed as potential children or as a base ...
Hammoud Ibrahim - - 2008
OBJECTIVE: To evaluate the pertinence of kinetic observations of embryonic development 25 hours after IVF, with a view to optimizing the choice of embryos for transfer. DESIGN: Retrospective study of 471 cycles with embryo transfer. SETTING: University Hospital. INTERVENTION(S): Observations of changes in zygotes, in the 25th hour after insemination ...
Vandaele Leen - - 2007
Embryo quality is most frequently evaluated at the blastocyst stage, although quality parameters further back along the developmental axis, such as early developmental kinetics or oocyte quality, can be equally valuable. Despite the fact that previous studies in bovine have linked oocyte diameter and early developmental kinetics with blastocyst formation ...
Mellor D J - - 2007
The neuroanatomical and neurophysiological development of the embryo and fetus and unique features of the physiological environment of the fetal brain, features which are lost at birth, support recent conclusions that under normal circumstances awareness (or consciousness) is probably not exhibited by the ovine embryo-fetus before birth and that it ...
Chorfi Younès - - 2007
The objective of this study was to determine the relationship between the number of transferable embryos (TE) and various blood chemistry parameters as a reflection of the metabolic state of cows after superovulatory treatment. Forty-nine Holstein cows were subjected to superovulatory treatment for commercial embryo production. At the time of ...
Rehman Khurram S - - 2007
OBJECTIVE: To define and validate metrics of embryo progression and morphology during extended embryo culture and to compare the effects of early cleavage (EC) vs. blastulation stages on clinical pregnancy. DESIGN: Retrospective observational study. SETTING: University-affiliated assisted reproduction center. PATIENT(S): One thousand two hundred ninety-two intracytoplasmic sperm injection and 842 ...
Liu Wei-Xin - - 2007
This study assessed whether the implantation potential of embryos that were partially damaged after freezing and thawing can be improved by removal of necrotic blastomeres. We retrospectively analyzed the pregnancy rate and implantation rate of 170 human frozen embryo transfer cycles. Laser-assisted hatching and micromanipulation were performed to remove the ...
Terriou P - - 2007
The aim of this study was, firstly, to define the different patterns of early cleavage (EC) observed at 26 h after either IVF or intracytoplasmic sperm injection (ICSI) and, secondly, to assess the predictive value of one of these patterns, even EC (EEC), on pregnancy rate in combination with day ...
Al-Hasani Safaa - - 2007
Cryopreservation of human oocytes and embryos is a necessary tool in assisted reproduction treatment that leads to an increased cumulative outcome while decreasing costs. Vitrification is a cryopreservation technique that leads to a glass-like solidification, with rapid cooling of cells or tissues. Nowadays vitrification is claimed to be the future ...
Merton J S - - 2007
Many environmental conditions for in vitro embryo production (IVP) systems for cattle have been relatively standardised, e.g. media composition, temperature, pH, water quality, and atmospheric composition. However, little attention has been paid to the quality of ambient laboratory air and the gas environment in incubators. Although a few studies have ...
Arroyo Gemma - - 2007
To relate pronuclear patterns (PN) and zygote cytoplasmic appearance and embryo morphology. The usefulness of PN classification described by Tesarik et al. 1999 (patterns p0-5) and Scott et al. 2000 (Z1-4), for embryo selection is assessed. Sinchrony on polarization and number of nucleolar precursor bodies (NPB) were associated with good ...
Hong Q-H - - 2007
The aim of this study was to investigate the effects of different vitrification solutions [EFS30 or EFS40 contains 30% (v/v) ethylene glycol (EG), 40% (v/v) EG; EDFS30 or EDFS40 contains 15% (v/v) EG and 15% (v/v) dimethyl sulfoxide (DMSO), 20% (v/v) EG and 20% (v/v) DMSO], equilibrium time during vitrification ...
Warkentin Karen M - - 2007
Prey assessing risk may miss cues and fail to defend themselves, or respond unnecessarily to false alarms. Error rates can be ameliorated with more information, but sampling predator cues entails risk. Red-eyed treefrogs have arboreal eggs and aquatic tadpoles. The embryos use vibrations in snake attacks to cue behaviorally mediated ...
Desai Nina - - 2007
Vitrification technology has shown great promise for cryopreservation of human embryos. The majority of this work has been with blastocyst-stage embryos. This report describes initial clinical results following vitrification of human embryos on day 3 of culture at the 6- to 8-cell stage. A total of 236 embryos were cryopreserved ...
Chagas e Silva J - - 2008
This prospective and randomised experiment was designed to compare the luteotrophic effect of whole versus half embryos and, to evaluate the relationship between the plasma progesterone (P4) profiles and the rates of early embryonic (from Days 7 to 25), late embryonic (Days 25-42) and foetal (Days 42-63) mortalities of whole ...
Patrizio P - - 2007
The vast majority of embryos produced in vitro and transferred fail to develop into an infant, supporting the concept that only a small fraction of embryos is destined to become a live birth. One of the main reasons for such a low embryo-to-infant ratio is the remarkably high number of ...
Stumm Camila L - - 2007
Blastocyst reception and implantation require various adaptations of the uterine microenvironment. We have previously shown that in mice, remodeling of the extracellular matrix begins early in pregnancy, characterized by synthesis, degradation and alteration of collagen fibrillogenesis, accompanied by pregnancy stage-dependent expression of glycosaminoglycans and proteoglycans. Fibrillin-1 is a matrix glycoprotein ...
Talent Nadia - - 2007
Apomixis in Crataegus is primarily aposporous and requires pollination. The embryo sac is of the Polygonum type. A combination of meiotically unreduced embryo sacs with apparently reduced pollen would violate the usual requirement for a 2 : 1 ratio of maternal to paternal contributions to the endosperm. We therefore investigated ...
Fuller Barry J - - 2007
The cryopreservation of mammalian embryos has expanded over the past 20 yr by encompassing a range of sophisticated methods to deal with different developmental stages and different sensitivities to low-temperature exposure. We have described a method for slow, controlled-rate freezing of early stage embryos based on exposure to 1,2-propanediol and ...
Pierce Lain X - - 2007
Patterning of zebrafish and other vertebrate embryos proceeds according to consistent, predictable developmental time courses. Because zebrafish spawn primarily during the first few hours after dawn, many important developmental stages typically occur during the middle of the night. As an automatic, accurate way to fix embryos at these inconvenient times, ...
Linklater W L - - 2007
Many sex allocation mechanisms are proposed but rarely have researchers considered and tested more than one at a time. Four facultative birth sex ratio (BSR) adjustment mechanisms are considered: (1) hormone-induced conception bias; (2) sex-differential embryo death from excess glucose metabolism; (3) sex-differential embryo death from embryo-uterine developmental asynchrony; and ...
Patrizio P - - 2007
The vast majority of embryos produced in vitro and transferred fail to develop into an infant, supporting the concept that only a small fraction of embryos is destined to become a live birth. One of the main reasons for such a low embryo-to-infant ratio is the remarkably high number of ...
Sega Martiana F - - 2007
Epigenetic modification of core histone proteins plays an important role in gene transcription and chromatin structure. It is known that the methylation status of the lysine 9 residue of histone H3 (H3K9) is closely linked with repression of transcription and heterochromatin formation. It has been reported that a strict asymmetric ...
Tibary A A Department of Veterinary Clinical Sciences, Center for Reproductive Biology, Washington State University, Pullman, WA 99164-6610, USA. - - 2007
Reproductive biology research on camelids offers some interesting peculiarities and challenges to scientists and animal production specialists. The objective of this paper is to review camelid reproduction, advances in reproductive physiology and reproductive biotechnologies in camelids and discuss some areas for further research. In the female, the focus has been ...
Rebmann Vera - - 2007
Human leukocyte antigen G (HLA-G) molecules are crucial for the maternal tolerance against the fetus during pregnancy. Thus, the presence of soluble HLA-G (sHLA-G) in embryo cultures is thought to be correlated to a successful pregnancy after assisted reproductive techniques (ART). Here, we established a rapid detection assay based on ...
Gilbert L - - 2007
Maternal effects occur when offspring phenotype is affected by environmental factors experienced by the mother and, in egg-laying species, are often mediated via egg resources. There is currently great interest among behavioural ecologists in maternally allocated yolk androgens, especially their relationship with offspring sex and development. Such studies need embryonic ...
Gil Mónica - - 2007
To analyze the results of our transferred embryos, especially those that "changed" their blastomere nuclearity from Multinucleated (MN) to Mono-nucleated during development. Pregnancies where at least one MN embryo was transferred were retrospectively evaluated and categorized in order to record and follow-up on the ones that were implanted. Embryos were ...
Nomura Masao - - 2007
To investigate the cleavage stage embryo quality by the correlation between the morphological features and blastocyst development rate to develop a new embryo grading system. A retrospective analysis, including 216 cycles of cleavage stage embryo transfer and 251 cycles of blastocyst transfer. The correlation with blastocyst development of the embryo ...
Rajamohan A - - 2007
This report presents details of a vitrification methodology for the cryopreservation of embryos of the Mexican fruit fly, Anastrepha ludens. The overall summary of the data indicates that selecting the correct developmental stage for cryopreservation is the most important criterion. The key aspect in selection of the correct stage is ...
Fiegel H C - - 2006
INTRODUCTION: Dilatation and impaired function of the gut is a condition often seen in newborns with bowel obstruction caused by intestinal atresia. In a previous experimental study in chicken embryos, we established a model to study ultrastructural changes during the development of the enteric nervous system after small bowel ligation. ...
Sawamura Chigusa - - 2006
To examine the effect of immobilization on the development of articular cartilage, we assessed glycosaminoglycan (GAG) content in the chick articular surface by delayed gadolinium-enhanced MRI of cartilage (dGEMRIC). Chick embryos were paralyzed by decamethonium bromide (DMB) from day 10 to either day 13 or day 16. The GAG content ...
López Teijón M - - 2006
Although embryos can theoretically be frozen for an unlimited period of time, there is still uncertainty about how long embryos can be cryopreserved without compromising pregnancy outcome. Following transfer of fresh embryos obtained after IVF, surplus embryos are usually frozen for personal use in later treatments. A 40-year-old woman was ...
Markham Rebecca G RG Department of Psychology, Florida International University, Miami, FL 33199, - - 2006
Neonatal studies suggest elevated arousal can negatively influence perceptual and cognitive processes during early development. The authors explored this issue during the prenatal period by pharmacologically elevating physiological arousal in bobwhite quail (Colinus virginianus) embryos during exposure to a maternal call, then assessing preference for the familiar call following hatching. ...
Glujovsky Demián - - 2007
OBJECTIVE: To evaluate clinical and assisted reproductive technology (ART) cycle variables related to spontaneous embryo reduction. DESIGN: Observational retrospective cohort study. SETTING: Private ART center. PATIENT(S): A total of 3,467 patients achieving a first-trimester pregnancy after IVF. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Rate of any spontaneous embryo reduction and rate ...
Yang Qi-En - - 2007
In the present study, mouse blastocysts were employed to investigate the feasibility and efficiency of stepwise in-straw dilution and direct transfer using the open pulled straw (OPS) method. In experiment I, the effects of various vitrification solutions (VS) on embryo survival were examined. After thawing, the expanded blastocyst rates (97.59 ...
Wang Haibin H Department of Pediatrics, Division of Reproductive and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232, - - 2007
Preimplantation embryo development to the blastocyst stage and uterine differentiation to the receptive state are prerequisites for embryo implantation. Burgeoning evidence suggests that endocannabinoid signaling is critical to early pregnancy events. Anandamide (N-arachidonoylethanolamine) and 2-AG (2-arachidonoylglycerol) are two major endocannabinoids that bind to and activate G-protein coupled cannabinoid receptors CB1 ...
Lopes A S - - 2007
BACKGROUND: Quantification of oxygen consumption by individual preimplantation embryos has the potential to improve embryo selection. This study investigated whether respiration rates of individual embryos are useful indicators of embryo viability. The effect of the Nanorespirometer on embryo viability was also evaluated. METHODS: The respiration rates of individual day 7 ...
Vega-López Armando - - 2007
Goodeid fish have matrotrophic viviparity, and unlike lecitotrophic fish, yolk loss forces the female to provide the nutritional requirements for embryonic development. Vitellogenin (VTG) is the yolk precursor protein synthesized in the maternal liver, but there is only circumstantial evidence regarding VTG supply during the ontogenesis of bony fish with ...
Petersen Claudia Guilhermino - - 2006
Laser-assisted hatching is little documented in the literature regarding its efficacy in cryopreserved-thawed (CT) embryo transfer cycles. The aim of the present study was to evaluate in a randomized manner the efficacy of thinning one quarter of the zona pellucida of CT embryos to a depth of 50-80% of the ...
Nichols Krista M - - 2007
Effects of maternal cytoplasmic environment (MCE) on development rate in rainbow trout were evaluated within a quantitative trait loci (QTL) analysis framework. Previous research had identified QTL for development rate in doubled haploid (DH) progeny produced from a cross between the Oregon State University (OSU) and the Swanson (SW) River ...
Sommer Jeffrey R - - 2007
An efficient protocol was developed to synchronize and superovulate mature pigs for the collection of pronuclear stage embryos suitable for DNA microinjection. A timed and coordinated regimen of Lutalyse, PG600 and Chorulon along with daily checking for estrus allowed synchronization of groups of gilts having estrous cycles at regular intervals. ...
de Graaf S P - - 2007
An experiment was undertaken to assess the fertilizing capacity of sex-sorted, frozen-thawed ram spermatozoa, artificially inseminated into superovulated ewes, and the quality and survivability of the resultant pre-sexed embryos. Synchronized (intravaginal progestagen pessary and GnRH) donors were superovulated using PMSG and repeat ovarian stimulation with FSH before insemination. Ewes (n=67) ...
Romano Juan E - - 2007
The objective was to estimate the effect of palpation per rectum (for early pregnancy diagnosis) on embryo/fetal viability in dairy cattle. A controlled, randomized block-design experiment with two blocks, one by category, and the other by number of embryos, was conducted. Five-hundred-and-twenty pregnant dairy cows and heifers with a viable ...
Lu Chenggang - - 2007
The C. elegans embryo supports both meiotic and mitotic spindles, requiring careful regulation of components specific to each spindle type. The MEI-1/katanin microtubule-severing complex is required for meiosis but must be inactivated prior to mitosis. Downregulation of MEI-1 depends on MEL-26, which binds MEI-1, targeting it for degradation by the ...
Fujino Yukihiro - - 2007
The viability or developmental ability of porcine embryos after slow-freezing and thawing differs depending on the embryonic stage or the batch, which is defined as a group of embryos obtained from one donor at one time. We froze porcine blastocysts in batches and assessed their cryotolerance by using two expanded ...
Scott L - - 2007
BACKGROUND: Many different embryo selection criteria have been used in assisted reproductive technologies (ART), but there are no published prospective studies to ascertain their usefulness in predicting implantation. METHODS: In a prospective trial, 20 early scoring parameters previously reported to influence clinical outcome were collected, but embryos were selected for ...
Sifer Christophe - - 2006
A retrospective study was performed to determine the differences in embryo survival and frozen-thawed embryo transfers outcome between cryopreservation performed on day 3 versus day 2. We conclude that freezing supernumerary embryos on day 3 provides similar thawing survival parameters, better implantation, pregnancy, and live-birth rates compared with day 2 ...
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