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Fresh Embryos (fresh + embryo)
Terms modified by Fresh Embryos Selected AbstractsAcquisition of desiccation tolerance in developing wheat embryos correlates with appearance of a fluid phase in membranesPLANT CELL & ENVIRONMENT, Issue 11 2003E. A. GOLOVINA ABSTRACT Membrane behaviour in developing wheat (Triticum aestivum cv Priokskaya) embryos was studied in relation to the acquisition of desiccation tolerance, using spin probe techniques. Fresh embryos were able to develop into seedlings at day 15 after anthesis, but it took 18 d before fast-dried, isolated embryos could germinate. On the basis of membrane integrity measurements it was estimated that between 14 and 18 d after anthesis the proportion of embryonic cells surviving fast drying increased and the critical moisture content, to which embryonic cells could be dehydrated, decreased. Apparently, embryonic cells do not acquire the same level of desiccation tolerance simultaneously. Only when all cells had become desiccation tolerant was germination of air-dried embryos possible. Using 5-doxylstearic acid as the probe molecule, an approximately similar lipid,water interface ordering of membranes was observed in all hydrated embryos, irrespective of age. Dehydration had a dual effect on the lipid interface: further ordering of the major part of the interface and the appearance of additional, disturbed regions. The proportion of these regions correlated with the proportion of desiccation-tolerant cells. We propose that the membrane surface disturbance be caused by endogenous amphiphiles that partition from the cytoplasm into membranes during drying. The absence of such disturbed regions in dried, desiccation-sensitive embryos might reflect a lack of sufficient amphiphiles. The relevance of membrane surface disturbance for desiccation tolerance is discussed. [source] Determination of sex and scrapie resistance genotype in preimplantation ovine embryosMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 2 2009Florence Guignot Abstract The aim of this study was to test the accuracy of genotype diagnosis after pre-amplification of DNA extracted from biopsies obtained by microblade cutting of ovine embryos and to evaluate the viability of biopsied embryos after vitrification/warming and transfer to recipients. Sex and PrP genotypes were determined. Sex diagnosis was done by PCR amplification of ZFX/ZFY and SRY sequences after PEP-PCR while PrP genotype determination was performed after specific pre-amplification of specific target including codons 136, 154 and 171. Embryos were collected at Day 7 after oestrus. Blastocysts and expanded blastocysts were biopsied immediately after collection whereas compacted morulae were biopsied after 24 hr of in vitro culture. Eighty-nine biopsied embryos were frozen by vitrification. Fresh and vitrified whole embryos were kept as control. DNA of biopsies was extracted and pre-amplified. Sex diagnosis was efficient for 96.6% of biopsies and PrP genotyping was determined in 95.8% of codons. After embryo transfer, no significant difference was observed in lambing rate between biopsied, vitrified control and fresh embryos (54.5%, 60% and 66.6%, respectively). Embryo survival rate was not different between biopsied and whole vitrified embryos (P,=,0.38). At birth, 96.7% of diagnosed sex and 95.4% of predetermined codons were correct. Lamb PrP profiles were in agreement with parental genotype. PEP-PCR coupled with sex diagnosis and nested PCR coupled with PrP genotype predetermination are very accurate techniques to genotype ovine embryo before transfer. These original results allow planning of selection of resistant genotype to scrapie and sex of offspring before transfer of cryopreserved embryo. Mol. Reprod. Dev. 76: 183,190, 2009. © 2008 Wiley-Liss, Inc. [source] Fertilisation and pregnancy outcome after ICSI in globozoospermic patients without assisted oocyte activationANDROLOGIA, Issue 1 2009S. Bechoua Summary The successful outcome of intracytoplasmic sperm injection (ICSI) with globozoospermic sperm and non-activated oocytes is reported. Three couples underwent ICSI treatment and two of the patients were siblings. Forty-four non-activated oocytes were injected, 26 oocytes fertilised normally and 17 good quality embryos were obtained. Six embryo transfers were carried out, three with fresh embryos and three with frozen-thawed embryos. Three pregnancies resulted from the fresh embryo transfers and additionally two pregnancies were obtained after the transfer of frozen-thawed embryos. Two healthy babies were born. One twin pregnancy is ongoing. Our case reports demonstrate that in some ICSI attempts undertaken with globozoospermic sperm cells from two of our patients, high fertilisation rates, pregnancies and live births can be achieved, without artificially activated oocytes. Our data also suggest that in some cases, round-headed spermatozoa lack the capacity to activate the oocyte. Therefore, it cannot be excluded that artificial oocyte activation could be of help in globozoospermic patients with complete fertilisation failure. [source] DONATING FRESH VERSUS FROZEN EMBRYOS TO STEM CELL RESEARCH: IN WHOSE INTERESTS?BIOETHICS, Issue 9 2007CAROLYN MCLEOD ABSTRACT Some stem cell researchers believe that it is easier to derive human embryonic stem cells from fresh rather than frozen embryos and they have had in vitro fertilization (IVF) clinicians invite their infertility patients to donate their fresh embryos for research use. These embryos include those that are deemed ,suitable for transfer' (i.e. to the woman's uterus) and those deemed unsuitable in this regard. This paper focuses on fresh embryos deemed suitable for transfer , hereafter ,fresh embryos', which IVF patients have good reason not to donate. We explain why donating them to research is not in the self-interests specifically of female IVF patients. Next, we consider the other-regarding interests of these patients and conclude that while fresh embryo donation may serve those interests, it does so at unnecessary cost to patients' self-interests. Lastly, we review some of the potential barriers to the autonomous donation of fresh embryos to research and highlight the risk that female IVF patients invited to donate these embryos will misunderstand key aspects of the donation decision, be coerced to donate, or be exploited in the consent process. On the basis of our analysis, we conclude that patients should not be asked to donate their fresh embryos to stem cell research. [source] |