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1
Nau, Jean-Yves. "Embryon humain, président républicain." Revue Médicale Suisse 8, no. 331 (2012): 548a—549a. http://dx.doi.org/10.53738/revmed.2012.8.331.548a.
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L. D. "Création d’un embryon mi-humain mi-animal." Bio Tribune Magazine 24, no. 1 (2007): 5. http://dx.doi.org/10.1007/bf03010318.
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Jouannet, Pierre. "CRISPR-Cas9, cellules germinales et embryon humain." Biologie Aujourd'hui 211, no. 3 (2017): 207–13. http://dx.doi.org/10.1051/jbio/2017032.
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Alessio, Renata L. Dos S., Thémistoklis Apostolidis, Maria de Fátima de S. Santos, and Lionel Dany. "Représentations sociales et embryon humain : une étude comparative Brésil / France." Les cahiers internationaux de psychologie sociale Numéro 92, no. 4 (2011): 371. http://dx.doi.org/10.3917/cips.092.0371.
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Nau, J. Y. "Des cellules souches issues d’un embryon humain obtenu par clonage." Revue Médicale Suisse 62, no. 2471 (2004): 469. http://dx.doi.org/10.53738/revmed.2004.62.2471.0469.
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Giraud, Anne-Sophie. "L’embryon humain en AMP, éléments pour une approche relationnelle." Enfances, Familles, Générations, no. 21 (July 22, 2014): 48–69. http://dx.doi.org/10.7202/1025959ar.
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L’analyse socio-anthropologique de la parenté en assistance médicale à la procréation (AMP) présuppose, qu’on le sache ou non, de donner un certain statut à l’embryon. Cependant, ce statut reste encore largement un point aveugle du débat des sciences sociales. L’anthropologie a beaucoup analysé la façon dont les techniques, et en particulier l’échographie, ont contribué à l’image de l’embryon comme « isolat », séparé en particulier du corps féminin dans lequel il était autrefois enclos et enfoui (Strathern, 1992). L’AMP, avec la congélation et la fécondation in vitro, a encore accentué cette représentation. Cependant, l’observation ethnographique des pratiques d’AMP révèle que l’embryon est en réalité toujours pris dans des réseaux relationnels (Thompson, 2005). Relations, d’une part, à des professionnels qui ont à un certain moment, du fait de leur statut, le pouvoir de sélectionner, détruire ou conserver cet embryon. D’autre part, et surtout, en référence à la parenté, à l’ensemble des personnes impliquées dans la procréation, l’engendrement ou la filiation, et qui de ce fait ont elles aussi un ensemble de pouvoirs et de devoirs à l’égard de cet embryon. Cet article s’appuie sur une enquête par entretiens semi-directifs auprès de 70 professionnels de l’AMP et a pour objectif d’analyser l’embryon en AMP grâce à une approche relationnelle inspirée de l’héritage maussien en matière d’analyse du genre et de la parenté (Théry, 2007). Cette approche permet de décrire autrement la scène de l’AMP et de comprendre comment l’embryon alterne entre diverses positions – entre enfant potentiel et pur matériau organique – selon le système de relations instituées dans lequel il se trouve inscrit. Notre hypothèse est qu’une telle approche éclaire de façons nouvelles les dilemmes parfois aigus des « parents » confrontés à l’embryon congelé hors projet et aux quatre grandes options prévues par la loi française : garder, donner à la recherche, « donner » à un autre couple ou détruire.
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Nau, Jean-Yves. "Le premier embryon humain transgénique a vu le jour aux Etats-Unis." Revue Médicale Suisse 4, no. 158 (2008): 1291. http://dx.doi.org/10.53738/revmed.2008.4.158.1291.
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Nau, Jean-Yves. "Feu vert britannique pour la production in vitro d’un embryon humain issu de deux femmes." Revue Médicale Suisse 1, no. 33 (2005): 2189. http://dx.doi.org/10.53738/revmed.2005.1.33.2189.
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Gaudreault, Marie-Claude. "L’embryon en droit français : titulaire d’un statut juridique ?" Revue générale de droit 28, no. 4 (2016): 467–93. http://dx.doi.org/10.7202/1035617ar.
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Les récents progrès de la biotechnologie ont mené à d’importantes découvertes dans le domaine des sciences de la vie et de la reproduction humaine. Lorsqu ’il s’agit de l’embryon humain, il n’en fallait pas plus pour relancer le débat quant à sa qualification juridique. Dans la mesure où la question s’est posée dès l’époque du droit romain, la problématique n’a donc vraiment de nouveau que le contexte dans lequel elle est maintenant soulevée : la procréation médicalement assistée. Par un rappel historique, l’auteure nous présente les diverses règles qui ont trouvé et qui continuent toujours de trouver application selon le droit civil français. L’on constatera ainsi que le droit a toujours hésité à reconnaître une personnalité juridique à l’enfant conçu. Par la suite, l’analyse s’arrête aux modifications apportées à la législation française en juillet 1994, par les lois dites « bioéthiques ». Encore une fois, la question semble simple; sommes-nous en présence d’un sujet ou d’un objet de droit ? Sans définir de statut précis pour l’embryon humain, le législateur français vient, par cet ensemble de lois, à tout le moins encadrer pour la première fois l’assistance médicale à la procréation et par le fait même, établir une protection pour tout embryon issu de cette dernière.
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Abid, B., R. Douard, N. Hentati, et al. "Reconstruction tridimensionnelle informatisée du segment rétrohépatique de la veine cave inférieure d’un embryon humain de 20mm." Morphologie 97, no. 317 (2013): 59–64. http://dx.doi.org/10.1016/j.morpho.2013.04.002.
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WANG, Hongqi. "生物醫學技術發展應該改變14天法則限制嗎？". International Journal of Chinese & Comparative Philosophy of Medicine 19, № 2 (2021): 87–91. http://dx.doi.org/10.24112/ijccpm.191949.
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LANGUAGE NOTE | Document text in Chinese; abstract also in English.
 Developments in research have made culturing human embryos beyond the 14-day limit seem technologically feasible. In the article “Emerging Human Embryo Research Technologies, the 14-day Rule, and the Special Status of the Embryo,” the authors examine a proposal for new human embryo and embryoid research guidelines by reviewing the history of the 14-day limit and emerging areas of research that are impacted by these guidelines. However, as noted by the authors, changes in science policy should not be developed solely by scientists. Instead, policy development should reflect the reality of science as a public endeavor. After 40 years of consensus, any attempts to revoke the 14-day limit on the in vitro culturing of human embryos should rely on public and stakeholder engagement.
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Matthews, Kirstin RW, and Daniel Moralí. "National human embryo and embryoid research policies: a survey of 22 top research-intensive countries." Regenerative Medicine 15, no. 7 (2020): 1905–17. http://dx.doi.org/10.2217/rme-2019-0138.
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Research using human embryos and embryoids has expanded in recent years due to technological advances. Surveying laws and guidelines among the top research and development (R&D) investing nations highlights existing barriers to expanding this area of research. Of the 22 nations surveyed, we found 12 countries with a 14-day limit, one with a seven-day limit, five with prohibitions and four without national laws or guidelines that limit or prohibit human embryo research. Sixteen national laws or guidelines define an embryo or related entities, with five nations limiting human embryoid research. Other laws are ambiguous in relation to embryoid research, leave unanswered questions regarding what research is permitted or restricted and need additional clarity for researchers.
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Casini, Carlo, and Marina Casini. "La fine del concetto di “pre-embrione” nella Convenzione di Oviedo / The end of the concept of “pre-embryo” in the Oviedo Convention." Medicina e Morale 66, no. 6 (2018): 735–45. http://dx.doi.org/10.4081/mem.2017.517.
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Il contributo si sofferma sulla questione riguardante la ricerca scientifica sugli embrioni generati in vitro. L’articolo 18 della Convenzione riguarda specificamente la sperimentazione sull’embrione in vitro e per questo esso è sottoposto ad una riflessione particolarmente approfondita. L’obiettivo è quello di capire se dalla Convenzione emergono linee idonee a definire lo statuto giuridico dell’embrione umano. Gli Autori concludono nel senso che nonostante il concetto di pre-embrione (formulato proprio per teorizzare l’insignificanza dell’embrione umano nei primi 14 giorni dalla fecondazione) sia stato accolto in alcune leggi e abbia implicitamente guidato l’interpretazione di alcuni aspetti relativi alla valutazione del valore dell’embrione, la Convenzione di bioetica lo ha definitivamente respinto con il massimo di autorevolezza. La conclusione è raggiunta attraverso l’esame dell’art. 18 considerandone anche la precedente formulazione contenuta in una bozza; mediante una interpretazione sistematica della Convenzione che esige il riconoscimento del concepito, fin dalla fecondazione, come un “essere umano”; esaminando i contributi preparatori elaborati dalla Assemblea Parlamentare del Consiglio d’Europa e del Parlamento Europeo; prendendo in considerazione gli sviluppi della Convenzione di Oviedo con specifico riferimento al tema del pre-embrione. L’indagine si avvale poi anche di ampi riferimenti alla giurisprudenza della Corte europea dei diritti dell’uomo del Consiglio d’Europa, alla giurisprudenza della Corte di Giustizia dell’Unione Europea, ad alcune recenti decisioni della Corte Costituzionale italiana. ---------- The paper focuses on the question concerning scientific research on human embryos generated in vitro. Article 18 of the Oviedo Convention specifically concerns the experimentation on the in vitro embryos and for this reason it is subject to a particularly in-depth reflection. The goal is to understand if the Convention shows suitable lines to define the legal status of the human embryo. The authors conclude that despite the concept of pre-embryo (formulated to theorize the insignificance of the human embryo in the first 14 days of fertilization) has been accepted in some laws and has implicitly guided the interpretation of some aspects related to the evaluation of the value of the embryo, the Bioethics Convention definitively rejected it with the utmost authority. The conclusion is reached through the examination of the art. 18 also considering the previous formulation contained in a draft; through a systematic interpretation of the Convention which requires the recognition of the conceived, from the moment of fertilization, as a “human being”; examining the preparatory contributions prepared by the Parliamentary Assembly of the Council of Europe and the European Parliament; taking into consideration the developments of the Oviedo Convention with specific reference to the theme of the pre-embryo. The investigation also makes use of extensive references to the jurisprudence of the European Court of Human Rights of the Council of Europe, to the jurisprudence of the Court of Justice of the European Union, to some recent decisions of the Italian Constitutional Court.
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Ventruba, Pavel, Jana Žáková, Michal Ješeta, et al. "Aspects of embryo selection and their preparation for the formation of human embryonic stem cells intended for human therapy." Česká gynekologie 86, no. 1 (2021): 5–10. http://dx.doi.org/10.48095/cccg20215.
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DING, Chunyan. "論人體胚胎研究“軟法”修改之正當性". International Journal of Chinese & Comparative Philosophy of Medicine 19, № 2 (2021): 69–73. http://dx.doi.org/10.24112/ijccpm.191946.
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LANGUAGE NOTE | Document text in Chinese; abstract also in English.
 This commentary briefly discusses the substantive and procedural justifications for amending the longstanding 14-day rule, a soft-law limitation on the culturing of human embryos. The 14-day rule was established on the basis of general recognition of the human embryo's special status, accompanied by widespread public conversation and engagement. In principle, amending this rule would require the same substantive and procedural justifications. However, such justifications were absent prior to the lifting of the rule by the ISSCR in its 2021 guidelines. This article also discusses the value and importance of the 14-day rule to the development of human embryo research in the last three decades. Discarding the rule without the proper substantive and procedural justifications is likely to damage public trust and confidence in future human embryo research.
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Konc, János, Katalin Kanyó, Rita Kriston, Bence Somoskői, and Sándor Cseh. "Cryopreservation of Embryos and Oocytes in Human Assisted Reproduction." BioMed Research International 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/307268.
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Both sperm and embryo cryopreservation have become routine procedures in human assisted reproduction and oocyte cryopreservation is being introduced into clinical practice and is getting more and more widely used. Embryo cryopreservation has decreased the number of fresh embryo transfers and maximized the effectiveness of the IVF cycle. The data shows that women who had transfers of fresh and frozen embryos obtained 8% additional births by using their cryopreserved embryos. Oocyte cryopreservation offers more advantages compared to embryo freezing, such as fertility preservation in women at risk of losing fertility due to oncological treatment or chronic disease, egg donation, and postponing childbirth, and eliminates religious and/or other ethical, legal, and moral concerns of embryo freezing. In this review, the basic principles, methodology, and practical experiences as well as safety and other aspects concerning slow cooling and ultrarapid cooling (vitrification) of human embryos and oocytes are summarized.
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Zorina, I. M., C. M. Eldarov, S. A. Yarigina, et al. "Metabolomic profiling in culture media of day-5 human embryos." Biomeditsinskaya Khimiya 63, no. 5 (2017): 385–91. http://dx.doi.org/10.18097/pbmc20176305385.
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The aim of this study was to determine the changes of metabolomic profiles in embryonic culture media (ECM) for the evaluation of quality and implantation potential of human embryos. ECM (n=163) were collected on day 5 before transfer or cryopreservation. Some embryos were used in preimplantation genetic screening for detection of aneuploidy karyotypes. Samples were subdivided into groups according to embryo morphological classification (by Gardner), genetic analysis and implantation data. ECM were extracted with methanol, precipitates were separated by centrifugation and metabolite production of individual embryo was analysed by LC-MS (the positive ion mode). After peak detection and retention time alignment, data were analysed using the PCA algorithm. MS fingerprinting analysis of embryo culture medium showed significant differences between morphologically divided groups. Intragroup comparisons did not reveal differences between subclasses. Genetic screening of embryos revealed 33 aneuploid karyotypes. It was shown that chromosome number did not affect the metabolite profiles comparing with the normal group. The culture media of embryos that were positive or negative for successful implantation showed specific signatures that allowed to distinguish embryos with different outcomes.The characterization of ECMs by LC-MS may facilitate more accurate selection of the best embryo for the implantation, improving single-embryo transfer and thus eliminating the risk and undesirable effects of multiple pregnancies.
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STOCK-MYER, Sharyn E. "Mosaicism in Human Embryos: What Do We Know?" Fertility & Reproduction 04, no. 03n04 (2022): 120. http://dx.doi.org/10.1142/s2661318222740322.
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Preimplantation Genetic Testing for Aneuploidy (PGT-A) involves performing aneuploidy testing on the small number of cells biopsied from a preimplantation embryo. It is well established that aneuploidy is a common cause of implantation failure and miscarriage. In an ideal world, a measure of the chromosome status of the cells from the embryo would produce a highly specific result that would predict the fate of that embryo. One of the difficulties with PGT-A however, has been putative chromosomal mosaicism present in a proportion of tested embryos. Chromosome mosaicism became more widely reported following the use of Next Generation Sequencing (NGS) as a tool for performing PGT-A. This was due to the higher dynamic range of the NGS profiles that made mosaicism in the trophectoderm biopsy more visible. Around this same time the first study was published that followed the transfer of 18 mosaic embryos, resulting in the birth of six healthy babies ( Greco et al 2015 ). Since then, several publications have described the results of mosaic embryo transfers, including the work by Viotti et al 2021 which summarised the results of transferring 1000 mosaic embryos. These studies have the common theme that a mosaic embryo result does not clearly predict a negative pregnancy outcome, unlike a uniform aneuploid result. However, it may predict a reduced chance of pregnancy, and an increased chance of miscarriage, depending on the type of mosaicism. Reassuringly, a mosaic result in an embryo also does not seem to indicate a higher chance of having a baby with an abnormality than euploid embryos. Chromosomally mosaic embryos should not be discarded and should be considered for use with appropriate counselling of the patients.
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Pereira Daoud, Ana M., Mina Popovic, Wybo J. Dondorp, et al. "Modelling human embryogenesis: embryo-like structures spark ethical and policy debate." Human Reproduction Update 26, no. 6 (2020): 779–98. http://dx.doi.org/10.1093/humupd/dmaa027.
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Abstract BACKGROUND Studying the human peri-implantation period remains hindered by the limited accessibility of the in vivo environment and scarcity of research material. As such, continuing efforts have been directed towards developing embryo-like structures (ELS) from pluripotent stem cells (PSCs) that recapitulate aspects of embryogenesis in vitro. While the creation of such models offers immense potential for studying fundamental processes in both pre- and early post-implantation development, it also proves ethically contentious due to wide-ranging views on the moral and legal reverence due to human embryos. Lack of clarity on how to qualify and regulate research with ELS thus presents a challenge in that it may either limit this new field of research without valid grounds or allow it to develop without policies that reflect justified ethical concerns. OBJECTIVE AND RATIONALE The aim of this article is to provide a comprehensive overview of the existing scientific approaches to generate ELS from mouse and human PSCs, as well as discuss future strategies towards innovation in the context of human development. Concurrently, we aim to set the agenda for the ethical and policy issues surrounding research on human ELS. SEARCH METHODS The PubMed database was used to search peer-reviewed articles and reviews using the following terms: ‘stem cells’, ‘pluripotency’, ‘implantation’, ‘preimplantation’, ‘post-implantation’, ‘blastocyst’, ‘embryoid bodies’, ‘synthetic embryos’, ‘embryo models’, ‘self-assembly’, ‘human embryo-like structures’, ‘artificial embryos’ in combination with other keywords related to the subject area. The PubMed and Web of Science databases were also used to systematically search publications on the ethics of ELS and human embryo research by using the aforementioned keywords in combination with ‘ethics’, ‘law’, ‘regulation’ and equivalent terms. All relevant publications until December 2019 were critically evaluated and discussed. OUTCOMES In vitro systems provide a promising way forward for uncovering early human development. Current platforms utilize PSCs in both two- and three-dimensional settings to mimic various early developmental stages, including epiblast, trophoblast and amniotic cavity formation, in addition to axis development and gastrulation. Nevertheless, much hinges on the term ‘embryo-like’. Extension of traditional embryo frameworks to research with ELS reveals that (i) current embryo definitions require reconsideration, (ii) cellular convertibility challenges the attribution of moral standing on the basis of ‘active potentiality’ and (iii) meaningful application of embryo protective directives will require rethinking of the 14-day culture limit and moral weight attributed to (non-)viability. Many conceptual and normative (dis)similarities between ELS and embryos thus remain to be thoroughly elucidated. WIDER IMPLICATIONS Modelling embryogenesis holds vast potential for both human developmental biology and understanding various etiologies associated with infertility. To date, ELS have been shown to recapitulate several aspects of peri-implantation development, but critically, cannot develop into a fetus. Yet, concurrent to scientific innovation, considering the extent to which the use of ELS may raise moral concerns typical of human embryo research remains paramount. This will be crucial for harnessing the potential of ELS as a valuable research tool, whilst remaining within a robust moral and legal framework of professionally acceptable practices.
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Kimber, S. J., S. F. Sneddon, D. J. Bloor, et al. "Expression of genes involved in early cell fate decisions in human embryos and their regulation by growth factors." REPRODUCTION 135, no. 5 (2008): 635–47. http://dx.doi.org/10.1530/rep-07-0359.
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Little is understood about the regulation of gene expression in human preimplantation embryos. We set out to examine the expression in human preimplantation embryos of a number of genes known to be critical for early development of the murine embryo. The expression profile of these genes was analysed throughout preimplantation development and in response to growth factor (GF) stimulation. Developmental expression of a number of genes was similar to that seen in murine embryos (OCT3B/4,CDX2,NANOG). However,GATA6is expressed throughout preimplantation development in the human. Embryos were cultured in IGF-I, leukaemia inhibitory factor (LIF) or heparin-binding EGF-like growth factor (HBEGF), all of which are known to stimulate the development of human embryos. Our data show that culture in HBEGF and LIF appears to facilitate human embryo expression of a number of genes:ERBB4(LIF) andLIFRandDSC2(HBEGF) while in the presence of HBEGF no blastocysts expressedEOMESand when cultured with LIF only two out of nine blastocysts expressedTBN. These data improve our knowledge of the similarities between human and murine embryos and the influence of GFs on human embryo gene expression. Results from this study will improve the understanding of cell fate decisions in early human embryos, which has important implications for both IVF treatment and the derivation of human embryonic stem cells.
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Liu, Yanhe, Jay Natalwala, and Vincent Chapple. "#64 : Developmental Elasticity and Self-Correction: How Much Can Human Embryos “Stretch”?" Fertility & Reproduction 05, no. 04 (2023): 458. http://dx.doi.org/10.1142/s2661318223742340.
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Background and Aims: The recent clinical application of time-lapse videography has enabled detection of abnormal cleavage (ABNC) in in vitro cultured human embryos and the quantification of their developmental speed. However, growing evidence has highlighted the inter-laboratory transferability issue when involving morphokinetics measures for embryo selection, as different culture conditions and patient profiles are known to alter embryo morphokinetics. Having originally reported several ABNC phenomena, our recent birth outcome data also implied a potential self-correction mechanism in ABNC affected embryos. In this abstract, we review the most up-to-date evidence in this field and highlight the elastic nature of embryo development. Method: Literature review. Results: In this abstract, data from both our group and others are analyzed from 2 different aspects. First, we discuss both embryo and patient factors that have been shown to alter embryo morphokinetics. We also share evidence supporting the ability of embryos to be elastic in morphokinetics without losing the ability to implant. We therefore stress that caution ought to be taken when applying morphokinetics based embryo selection, especially when such models were developed using an external dataset. Secondly, we present the various impacts of ABNC when it occurs at different developmental stages and with different number of occasions. We also present the live birth rates and neonatal outcomes of ABNC embryos that had successfully achieved blastulation. Based on that, we propose blastulation as a self-correction milestone, supported by time-lapse footage showing exclusion/extrusion of ABNC-affected cells. Conclusion: Human embryos demonstrate detectable developmental elasticity which may be related to their ability to stand physical and chemical stress during in vitro culture. Embryos affected by ABNC can self-correct at blastulation by excluding/extruding affected cells. However, the limits of such elasticity in human embryos before losing their viability remain unknown.
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Tvrdonova, Katerina, Silvie Belaskova, Tatana Rumpikova, et al. "Differences in Morphokinetic Parameters and Incidence of Multinucleations in Human Embryos of Genetically Normal, Abnormal and Euploid Embryos Leading to Clinical Pregnancy." Journal of Clinical Medicine 10, no. 21 (2021): 5173. http://dx.doi.org/10.3390/jcm10215173.
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The selection of the best embryo for embryo transfer (ET) is one of the most important steps in IVF (in vitro fertilisation) treatment. Preimplantation genetic testing (PGT) is an invasive method that can greatly facilitate the decision about the best embryo. An alternative way to select the embryo with the greatest implantation potential is by cultivation in a time-lapse system, which can offer several predictive factors. Non-invasive time-lapse monitoring can be used to select quality embryos with high implantation potential under stable culture conditions. The embryo for ET can then be selected based on the determined morphokinetic parameters and morphological features, which according to our results predict a higher implantation potential. This study included a total of 1027 morphologically high-quality embryos (552 normal and 475 abnormal PGT-tested embryos) from 296 patients (01/2016–06/2021). All embryos were cultivated in a time-lapse incubator and PGT biopsy of trophectoderm cells on D5 or D6 was performed. Significant differences were found in the morphological parameters cc2, t5 and tSB and the occurrence of multinucleations in the stage of two-cell and four-cell embryos between the group of genetically normal embryos and abnormal embryos. At the same time, significant differences in the morphological parameters cc2, t5 and tSB and the occurrence of multinucleations in the two-cell and four-cell embryo stage were found between the group of genetically normal embryos that led to clinical pregnancy after ET and the group of abnormal embryos. From the morphokinetic data found in the PGT-A group of normal embryos leading to clinical pregnancy, time intervals were determined based on statistical analysis, which should predict embryos with high implantation potential. Out of a total of 218 euploid embryos, which were transferred into the uterus after thawing (single frozen embryo transfer), clinical pregnancy was confirmed in 119 embryos (54.6%). Our results show that according to the morphokinetic parameters (cc2, t5, tSB) and the occurrence of multinucleations during the first two cell divisions, the best euploid embryo for ET can be selected with high probability.
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Doronin, Yu K., I. V. Senechkin, L. V. Hilkevich, and M. A. Kurcer. "Cleavage of Human Embryos: Options and Diversity." Acta Naturae 8, no. 3 (2016): 88–96. http://dx.doi.org/10.32607/20758251-2016-8-3-88-96.
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In order to estimate the diversity of embryo cleavage relatives to embryo progress (blastocyst formation), time-lapse imaging data of preimplantation human embryo development were used. This retrospective study is focused on the topographic features and time parameters of the cleavages, with particular emphasis on the lengths of cleavage cycles and the genealogy of blastomeres in 2- to 8-cell human embryos. We have found that all 4-cell human embryos have four developmental variants that are based on the sequence of appearance and orientation of cleavage planes during embryo cleavage from 2 to 4 blastomeres. Each variant of cleavage shows a strong correlation with further developmental dynamics of the embryos (different cleavage cycle characteristics as well as lengths of blastomere cycles). An analysis of the sequence of human blastomere divisions allowed us to postulate that the effects of zygotic determinants are eliminated as a result of cleavage, and that, thereafter, blastomeres acquire the ability of own syntheses, regulation, polarization, formation of functional contacts, and, finally, of specific differentiation. This data on the early development of human embryos obtained using noninvasive methods complements and extend our understanding of the embryogenesis of eutherian mammals and may be applied in the practice of reproductive technologies.
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Herle, Dominik Janez. "Matične celice v službi življenja." Res novae: revija za celovito znanost 5, no. 2 (2020): 70–88. http://dx.doi.org/10.62983/rn2865.202.4.
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Human embryos should not be used to cure diseases because an embryo, from the moment of fertilization, is already a person who must be respected in an absolute way. An embryo has dignity as a human being, a person who is composed of body and soul. Because of being human, the embryo must be given the dignity of a human being. The great Christian and Greek philosophers recognized the human person in all its dignity. Stem cell research on embryos shows the violation of the rights of an embryo. To avoid immoral practice, doctors should instead use adult stem cells as a solution to a problem.
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Hardy, K., and S. Spanos. "Growth factor expression and function in the human and mouse preimplantation embryo." Journal of Endocrinology 172, no. 2 (2002): 221–36. http://dx.doi.org/10.1677/joe.0.1720221.
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There is increasing evidence that even before implantation, human development is regulated by embryonically and maternally derived growth factors. Studies in other mammalian species have shown that growth factors and their receptors are expressed by the preimplantation embryo and the reproductive tract. Furthermore, a number of growth factors have been shown to affect rate of embryo development, the proportion of embryos developing to the blastocyst stage, blastocyst cell number, metabolism and apoptosis. Growth factor ligands and receptors are also expressed in human embryos and the maternal reproductive tract, and supplementation of culture medium with exogenous growth factors affects cell fate, development and metabolism of human embryos in vitro. Autocrine, paracrine and endocrine pathways that may operate within the embryo and between the embryo and the reproductive tract before implantation are proposed.
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Gebhardt, K. M., D. Feil, M. Lane, and D. L. Russell. "262. Human cumulus cell gene expression as a marker of clinical embryo grade." Reproduction, Fertility and Development 20, no. 9 (2008): 62. http://dx.doi.org/10.1071/srb08abs262.
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In Australia, Assisted Reproductive Technology (ART) accounts for ~3% of births. However, the success rate remains around 65% for women under 35 years of age, hence multiple embryo transfer is frequently preferred to improve the probabiity of achieving a term pregnancy. A biochemical marker for oocyte and embryo developmental potential would augment successful pregnancy outcomes following IVF/ICSI by optimising oocyte and embryo selection, therefore increasing the number of single embryo transfers (SET) performed in ART cycles. Changes in expression levels in human cumulus cells may reflect the quality of their enclosed oocyte. We investigated cumulus cell gene expression and subsequent embryo development to find a marker of embryo quality. Paired samples of cumulus cells were collected from oocytes that progressed to embryos of either high or low grade from eleven IVF/ICSI patients. Following cumulus oocyte complex retrieval cumulus cells were trimmed from the oocyte, and all oocytes and resulting embryos were cultured and tracked individually. Cumulus cell gene expression was assessed using a real-time RT–PCR assay, measuring expression of cyclooxygenase 2 (COX2; PTGS2), Pentraxin 3 (PTX3), Versican (VCAN), Tumour Necrosis Factor Alpha Induced protein 6 (TNAIFP6; TSG6), Lactate Dehydrogenase A (LDHA), Phosphofructokinase Platelet (PFKP), Gremlin (GREM1), Glyceraldehyde-3-Phosphate Dehydrogenase (GAPDH) and 18S rRNA. Standard curves using plasmid subclones for each target were run to assess copy numbers of genes. Embryo morphology was assessed by an embryologist and correlated with relative gene expression. Cumulus cell gene expression was altered in cumulus cells from oocytes which subsequently developed into higher quality (Grade 1 and 2) embryos compared with cumulus cells from oocytes which developed into lower quality (Grade 3 and 4) embryos. This may lead to establishment of markers prognostic for developmental outcome, facillitating more reliable selection of higher quality embryos, increasing single embryo transfers and improving health outcomes from ART.
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Jones, GM. "Growth and viability of human blastocysts in vitro." Reproductive Medicine Review 8, no. 3 (2000): 241–87. http://dx.doi.org/10.1017/s0962279900000351.
Full textAbstract:
The transfer of a blastocyst established the first human clinical pregnancy following in vitro fertilization (IVF). Nine years later Cohen et al. reported pregnancies resulting from the transfer of cryopreserved human blastocysts. However, it was another six years before the first report of births resulting from the transfer of human blastocysts produced in vitro appeared in the medical literature. In the intervening period clinics have opted to transfer embryos at the early cleavage stage to the uterus, despite the fact that in vivo the embryo does not enter the uterus until two to three days later at the morula to blastocyst stage of development. The viability and potential for implantation of blastocysts is high, as indicated by the finding that more than 60% of in-vivo-derived blastocysts, recovered by uterine lavage following artificial insemination of fertile donors, implant and develop into viable fetuses when transferred to recipients. This is in stark contrast to the 10–20% of in-vitro-produced embryos transferred at the early cleavage stage of development that result in a live-birth. This reduction in viability following transfer of in-vitro-derived early cleavage stage embryos may have several possible explanations: (1) a failure of implantation due to poor synchronization between the embryo and the uterine endometrium; (2) a hostile environment in the uterus for early cleavage stage embryos; (3) sub-optimal in vitro culture conditions which result in a reduction in embryo viability; (4) the assumption that all oocytes retrieved in an IVF cycle have an equal ability to develop into viable embryos; and (5) the failure to identify the most viable embryo in a cohort. Certainly, improving culture conditions and laboratory techniques for developing high quality blastocysts routinely in vitro will not only address many of the above questions but will also improve the quality and viability of earlier stages of embryo development.
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UM, YOUNG-RHAN. "South Korea: Human Embryo Research." Cambridge Quarterly of Healthcare Ethics 12, no. 3 (2003): 268–78. http://dx.doi.org/10.1017/s0963180103123092.
Full textAbstract:
On May 18, 2001, the Korean Bioethics Advisory Commission (KBAC), sponsored by the Ministry of Science and Technology, published a set of recommendations for biotechnological research and application, including scientific experiments with human embryos. Four days later, the KBAC held a public hearing to finalize its recommendations. Since then, public reaction and debate over the ethical aspects of human embryo research have actively surfaced. Most leaders of religious organizations, especially Catholic churches, objected to any type of embryo research. On the other hand, some leaders of the scientific community supported freer scientific research on human embryos.
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Pallisco, Romina, Giacomo Lazzarino, Gabriele Bilotta, et al. "Metabolic Signature of Energy Metabolism Alterations and Excess Nitric Oxide Production in Culture Media Correlate with Low Human Embryo Quality and Unsuccessful Pregnancy." International Journal of Molecular Sciences 24, no. 1 (2023): 890. http://dx.doi.org/10.3390/ijms24010890.
Full textAbstract:
Notwithstanding the great improvement of ART, the overall rate of successful pregnancies from implanted human embryos is definitely low. The current routine embryo quality assessment is performed only through morphological criteria, which has poor predictive capacity since only a minor percentage of those in the highest class give rise to successful pregnancy. Previous studies highlighted the potentiality of the analysis of metabolites in human embryo culture media, useful for the selection of embryos for implantation. In the present study, we analyzed in blind 66 human embryo culture media at 5 days after in vitro fertilization with the aim of quantifying compounds released by cell metabolism that were not present as normal constituents of the human embryo growth media, including purines, pyrimidines, nitrite, and nitrate. Only some purines were detectable (hypoxanthine and uric acid) in the majority of samples, while nitrite and nitrate were always detectable. When matching biochemical results with morphological evaluation, it was found that low grade embryos (n = 12) had significantly higher levels of all the compounds of interest. Moreover, when matching biochemical results according to successful (n = 17) or unsuccessful (n = 25) pregnancy, it was found that human embryos from the latter group released higher concentrations of hypoxanthine, uric acid, nitrite, and nitrate in the culture media. Additionally, those embryos that developed into successful pregnancies were all associated with the birth of healthy newborns. These results, although carried out on a relatively low number of samples, indicate that the analysis of the aforementioned compounds in the culture media of human embryos is a potentially useful tool for the selection of embryos for implantation, possibly leading to an increase in the overall rate of ART.
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Walin, Laura. "Ambiguity of the Embryo Protection in the Human Rights and Biomedicine Convention: Experiences from the Nordic Countries." European Journal of Health Law 14, no. 2 (2007): 131–48. http://dx.doi.org/10.1163/092902707x199104.
Full textAbstract:
AbstractUntil 1998 research on in vitro human embryos concentrated on the issues related to assisted reproduction. The situation changed dramatically when the first scientific report on the laboratory culture of human embryonic stem cells was published. This scientific breakthrough with new therapeutic promises put human embryo into a new, more vulnerable position. Combined with creation of embryos via somatic cell nuclear transfer, it inveigles into mass production of embryos, first for scientific purposes, but later perhaps for the healing of people.This article examines the efficacy of the Convention on Human Rights and Biomedicine in protecting embryos in this new era of embryo research. The interpretative latitude of Article 18 of the Convention is demonstrated, and legislation in three Nordic countries with highly variable approach to embryo research regulation is analysed. I examine how this divergence is possible in the light of the Convention text. In the end, potential reasons for variation in regulation in the otherwise similar Nordic countries are discussed, as well as under what conditions harmonisation of regulation on embryo research, a highly value-charged matter, could be possible at the European level.
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Kustova, Maria E., Vasilina A. Sokolova, Oksana V. Kidgotko, Mikhail G. Bass, Faina M. Zakharova, and Vadim B. Vasilyev. "Distribution of introduced human mitochondrial DNA in early stage mouse embryos." Medical academic journal 20, no. 2 (2020): 69–78. http://dx.doi.org/10.17816/maj34657.
Full textAbstract:
Objective. The aim of study was the analysis of human mitochondrial DNA (mtDNA) distribution among murine blastomeres in the embryos developing after an injection of human mitochondria suspension at the stage of one or two cells is presented.
 Material and methods. Mice CBA/C57Black from Rappolovo aged three weeks were used. Zygotes were obtained upon hormonal stimulation of animals and mated with males. 310 pL of mitochondrial suspension from HepG2 cells was injected into a zygote or one blastomere of a two-cell embryo. Zygotes or two-cell embryos cultured in M3 medium drops covered with mineral oil in Petri dishes. Upon reaching the two-, four- or eight-cell stage the cultured embryos were separated into blastomeres. The latter were lysed and the total DNA was isolated. Human mtDNA was detected by PCR using species-specific primers.
 Results. The development of 2848 mouse embryos was monitored. In 520 embryos that achieved the stage of 2, 4, 8 in proper time the presence of human mtDNA was assayed in each blastomere. Along with murine mtDNA all embryos contained human mitochondrial genome, which is an evidence of artificially modelled heteroplasmy. Not every blastomere of transmitochondrial embryos contained foreign (human) mtDNA. Mathematical elaboration evidenced an uneven distribution of human mtDNA in cytoplasm within the time elapsed between the injection of human mitochondria and the subsequent splitting of the embryo.
 Conclusion. The results obtained confirm our previous notion of the presence of 1011 segregation units of human mtDNA in the total amount of mitochondria (about 5 ∙ 102) injected into an embryo.
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Dederer, Hans-Georg. "Der manipulierbare Embryo: Konsequenzen für das Recht." Jahrbuch für Recht und Ethik / Annual Review of Law and Ethics 28, no. 1 (2020): 53–82. http://dx.doi.org/10.3790/jre.28.1.53.
Full textAbstract:
Innovative techniques of developmental biology facilitate the artificial creation of embryo-like entities. This contribution analyses, first, whether certain artificially created embryo-like entities are ‘embryos’ within the meaning of existing statutory law definitions laid down in the Embryo Protection Act, the Stem Cell Act and the Patent Act. These definitions are non-uniform and their interpretation and application with regard to artificially created embryo-like entities is not always conclusive. Accordingly, the legal definitions of the term ‘embryo’ should be harmonised and, thereby, adapted to the state of developmental biology. Any such legislative efforts need to be in conformity with the constitution, primarily with the guarantee of human dignity (Article 1(1) of the Basic Law). However, said provision cannot provide guidance to the legislature because the constitutional status of both embryos and embryo-like entities in vitro is highly disputed. It is held that this irresolvable debate is due to a fundamental lack of a widely shared experience that such entities possess a supreme unique value. This article argues that in such a situation it is, in the first instance, for the legislature (i. e. parliament) to determine the legal status of embryos and embryo-like entities in vitro. This argument is based on a particular doctrinal approach according to which the individual right to respect of one’s human dignity arising from Article 1(1) BL depends on recognition of the relevant entity as being a ‘human’ or a member of ‘humankind’ respectively. Such recognition has, hitherto, not been accomplished with a view to embryos and embryo-like entities in vitro. Against this backdrop, for the time being, the legislature may determine the legal status of embryos and embryo-like entities in vitro, lay down rules regarding their creation and particular use, and, especially, define the legal term ‘embryo’, albeit within some outer constitutional limits. The article, finally, analyses several elements of, and submits a proposal for, a new legal definition of the term ‘embryo’.
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Gutierrez-Adan, Alfonso, Carlee R. White, Ann Van Soom, and Mellissa R. W. Mann. "Why we should not select the faster embryo: lessons from mice and cattle." Reproduction, Fertility and Development 27, no. 5 (2015): 765. http://dx.doi.org/10.1071/rd14216.
Full textAbstract:
Many studies have shown that in vitro culture can negatively impact preimplantation development. This necessitates some selection criteria for identifying the best-suited embryos for transfer. That said, embryo selection after in vitro culture remains a subjective process in most mammalian species, including cows, mice and humans. General consensus in the field is that embryos that develop in a timely manner have the highest developmental competence and viability after transfer. Herein lies the key question: what is a timely manner? With emerging data in bovine and mouse supporting increased developmental competency in embryos with moderate rates of development, it is time to question whether the fastest developing embryos are the best embryos for transfer in the human clinic. This is especially relevant to epigenetic gene regulation, including genomic imprinting, where faster developing embryos exhibit loss of imprinted methylation, as well as to sex selection bias, where faster developmental rates of male embryos may lead to biased embryo transfer and, in turn, biased sex ratios. In this review, we explore evidence surrounding the question of developmental timing as it relates to bovine embryo quality, mouse embryo quality and genomic imprint maintenance, and embryo sex.
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Shaw, Lisa, Sharon F. Sneddon, Daniel R. Brison, and Susan J. Kimber. "Comparison of gene expression in fresh and frozen–thawed human preimplantation embryos." REPRODUCTION 144, no. 5 (2012): 569–82. http://dx.doi.org/10.1530/rep-12-0047.
Full textAbstract:
Identification and characterisation of differentially regulated genes in preimplantation human embryonic development are required to improve embryo quality and pregnancy rates in IVF. In this study, we examined expression of a number of genes known to be critical for early development and compared expression profiles in individual preimplantation human embryos to establish any differences in gene expression in fresh compared to frozen–thawed embryos used routinely in IVF. We analysed expression of 19 genes by cDNA amplification followed by quantitative real-time PCR in a panel of 44 fresh and frozen–thawed human preimplantation embryos. Fresh embryos were obtained from surplus early cleavage stage embryos and frozen–thawed embryos from cryopreserved 2PN embryos. Our aim was to determine differences in gene expression between fresh and frozen–thawed human embryos, but we also identified differences in developmental expression patterns for particular genes. We show that overall gene expression among embryos of the same stage is highly variable and our results indicate that expression levels between groups did differ and differences in expression of individual genes was detected. Our results show that gene expression from frozen–thawed embryos is more consistent when compared with fresh, suggesting that cryopreserved embryos may represent a reliable source for studying the molecular events underpinning early human embryo development.
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Shurygina, O. V., G. B. Nemkovskiy, D. Y. Rusakov, et al. "MODERN APPROACHES TO CULTIVATION AND AUTOANALYSIS OF HUMAN EMBRYO MORPHODYNAMICS IN VIVO." Reproductive Medicine, no. 3(48) (September 20, 2021): 35–43. http://dx.doi.org/10.37800/rm.3.2021.35-43.
Full textAbstract:
Relevance: Currently, it is extremely important to identify predictors of the development of a competent embryo that determine its implantation potential. In this case, the predictors are predictive parameters that should be assessed together to rank and select human embryos.
 We introduced the concept of «human embryo morphodynamic profile» to standardize the description of the development of human embryos cultured in vitro. We identified a set of morphokinetic states that are included in the profile and located on the time scale depending on the moment of their registration. All timing cutoffs (points) are given in chronological order relative to the moment of fertilization.
 The purpose of the study was to implement an information system utilizing artificial intelligence technologies for an automated formation of the morphodynamic profile of a human embryo based on time-lapse photography of the process of human embryo cultivating to the blastocyst stage.
 Materials and methods: Visual information about the pre-implantation development of human embryos to the blastocyst stage (0 - 6 days from insemination) was collected using an «Embryovisor» incubator for IVF laboratories with a time-lapse (hyperlapse) video fixation system (LLC «WESTTRADE LTD,” Russia). The embryos were cultivated individually in special microwells of WOW dishes (Vitrolife, Sweden). Visual information about cultured human embryos was collected, marked, and prepared at the Laboratory of assisted reproductive technologies (ART) of the Clinical Hospital IDK CJSC “Medical Company IDK” (Group of Companies “Mother and Child,” Samara, Russia) and the medical center “Semya” (Ufa, Russia). The morphodynamic profile was marked using the EmbryoVisor software (customized version). Graphics and markup information was uploaded to the SberCloud cluster. A convolutional neural network for solving the multiclass classification task was implemented on the Christofari supercomputer of the SberCloud cluster.
 Results: Based on the available database, we have developed a system for forming the morphodynamic profile of a human embryo, taking into account the placement of markers of fixed morphokinetic states.
 Conclusion: The ability to record major morphodynamic events and assess them allows a more comprehensive approach to evaluating and ranking developing embryos and selecting the most promising embryo for implantation.
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Gazina, N. I. "Legal regimes for using human embryos for scientific purposes in the light of the international bodies’ practice." Courier of Kutafin Moscow State Law University (MSAL)), no. 7 (October 13, 2021): 153–59. http://dx.doi.org/10.17803/2311-5998.2021.83.7.153-159.
Full textAbstract:
The research on human embryos evolves rapidly, raising a number of ethical and legal issues and directly affecting human rights. Approaches to the legal regulation of human embryo research differ significantly from country to country. Some of them employ prohibitive practices (e.g. Switzerland and Italy), and the others have a regime that allows using embryos for scientific purposes with restrictions of different extent (e.g. the UK and Japan). There is no the international consensus on the issue of human embryo research. The objective of the article is to find out whether there are positions of the international bodies that may become or have already become the general guidance for different countries, allowing therefore to regulate effectively the use of human embryos for scientific purposes.The conclusion is drawn that there are positions of international bodies that may serve as the guidance within the regulation of the area concerned. States may enjoy a wide margin of appreciation within the framework of human embryo research regulation, considering the need to update their regulations regularly to harmonize them with the development of human rights and scientific progress and also to ensure a certain level of the embryo protection.
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Victoria, Sokaliuk (Galushko). "The Moral Status of the Human Embryo." Legal Ukraine 6, no. 6 (2021): 45–50. http://dx.doi.org/10.37749/2308-9636-2021-6(222)-6.
Full textAbstract:
Recognizing the importance of the state’s special protection of the prenatal stage of human development, most countries establish strict control over the research of the human embryo. One way to argue the limitations of embryo research is its moral status as a potential human being and representative of the human species. In the insufficient study of the moral status of the embryo, the article identifies approaches to its understanding and formulates its main features. The paper also examines the theoretical question that is at the heart of practical and professional ethics: by what criteria is the embryo attributed to have the moral status? The answer to this question reveals the importance of moral considerations regarding the proper handling of the embryos as well as the importance of the moral duty of others to treat an unborn child with respect. Some ways of understanding the principle of respect are examined separately. The moral significance, value, and respect for the embryo are all prerequisites for establishing the limits of acceptable and unacceptable behaviour during the research on human embryos. This article highlights the problem of conflict of interests of the embryo as the one with moral status, with the interests of society to continue embryonic research due to the potential for usefulness for a huge number of people suffering from various diseases. Such conflict can be resolved through the establishment of ethical principles, which can be used to describe the limits of research on human embryos in the international and national guidelines for such research. Given the generality of such principles, it is also important to establish a national specialized committee on the ethics of research on human embryos. Despite the results of the study, the article emphasizes the need for more detailed and deeper participation of representatives of legal, bioethical, embryological science, and the public in conversation. Key words: moral significance, value, respect, moral obligations, legal status.
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Bavister, Barry. "The role of animal studies in supporting human assisted reproductive technology." Reproduction, Fertility and Development 16, no. 7 (2004): 719. http://dx.doi.org/10.1071/rd04087.
Full textAbstract:
Although average success rates of human IVF have increased progressively during the past two decades, the efficiency of this technique, based on each embryo produced or transferred, is still low. High success rates are usually achieved by transferring several embryos to the patient, which is often associated with multiple pregnancies. The quality of in vitro produced embryos is a major area that needs attention. Because there is no in vivo database for human embryos, the properties of normal embryos are not known, and so it is difficult to know how to improve quality and viability. In addition, selection of the most viable embryos for transfer is a rather subjective process. The origins of human assisted reproductive technology (ART) are based on animal ART; however, the two areas of research (animal and human ART) appear to have become disconnected. Re-examination of progress in animal ART could help improve human embryo quality and thereby assist efforts to sustain high pregnancy rates with only one or two embryos transferred. Some key areas in which animal ART can help guide progress in human ART are discussed.
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Lansford, Rusty, and Sandra Rugonyi. "Follow Me! A Tale of Avian Heart Development with Comparisons to Mammal Heart Development." Journal of Cardiovascular Development and Disease 7, no. 1 (2020): 8. http://dx.doi.org/10.3390/jcdd7010008.
Full textAbstract:
Avian embryos have been used for centuries to study development due to the ease of access. Because the embryos are sheltered inside the eggshell, a small window in the shell is ideal for visualizing the embryos and performing different interventions. The window can then be covered, and the embryo returned to the incubator for the desired amount of time, and observed during further development. Up to about 4 days of chicken development (out of 21 days of incubation), when the egg is opened the embryo is on top of the yolk, and its heart is on top of its body. This allows easy imaging of heart formation and heart development using non-invasive techniques, including regular optical microscopy. After day 4, the embryo starts sinking into the yolk, but still imaging technologies, such as ultrasound, can tomographically image the embryo and its heart in vivo. Importantly, because like the human heart the avian heart develops into a four-chambered heart with valves, heart malformations and pathologies that human babies suffer can be replicated in avian embryos, allowing a unique developmental window into human congenital heart disease. Here, we review avian heart formation and provide comparisons to the mammalian heart.
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Morris, Samantha A. "Human embryos cultured in vitro to 14 days." Open Biology 7, no. 1 (2017): 170003. http://dx.doi.org/10.1098/rsob.170003.
Full textAbstract:
We know a great deal about the development of the mammalian embryo until the time that the blastocyst implants into the uterus. With model organisms such as the mouse, we have also developed a considerable understanding of development immediately around gastrulation as embryos can be recovered at this stage for short-term in vitro culture. However, the intervening period of development remained a ‘black box’ because it takes place as the blastocyst is implanting into the uterus. Over the past 6 years, techniques pioneered and developed in Magdalena Zernicka-Goetz's laboratory for the in vitro culture of embryos through these implantation stages have opened up this box, affording the first glimpse of embryonic development through these previously hidden stages. Remarkably, the techniques developed with mouse embryos are equally applicable to human embryos, ushering the very first opportunities for studying our own development throughout this time. Here, I outline how the culture methods were developed, paving the way to culture of the human embryo to the point of gastrulation, an accomplishment recognized as the People's Choice for the Scientific Breakthrough of 2016 in Science magazine. I also discuss the new ethical challenges raised by the possibility of extending the time limits for human embryo culture.
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Reed, Michael L., Bryan J. Woodward, and Jason E. Swain. "Single or Group Culture of Mammalian Embryos: The Verdict of the Literature." Journal of Reproductive and Stem Cell Biotechnology 2, no. 2 (2011): 77–87. http://dx.doi.org/10.1177/205891581100200203.
Full textAbstract:
During infertility treatment with IVF, embryos are cultured either in groups or individually. Each approach has potential benefits and detriments, and the purpose of this review is to try to come to a consensus based on the literature as to which approach yields superior results. Group culture of embryos may produce better quality embryos via secretion of embryotrophic factors, while opponents of the approach argue that embryos cultured together may either deplete the media of substrates or negatively affect nearby embryos via the transmission of other secreted factors. In these cases, quantity of embryos, volume of media and proximity and quality of companion embryos are also important factors to consider. While it has long been accepted that group culture is beneficial for embryos from various animal species, emerging data also suggest a similar benefit in the human. Conversely, embryos cultured individually avoid potential substrate depletion, negative impact from factors secreted from companion embryos, while more practically permitting the ability to monitor and track the embryo for identification via morphology or molecular analysis to select and transfer potentially superior embryos. Importantly, advancements in embryo culture platforms now permit tracking of individual embryos, while also offering ability to reap the benefits of group culture. These approaches utilize confined microenvironments immediately surrounding the embryos that may be conducive for periodic sampling/analysis, while also allowing access to a larger media reservoir to avoid substrate depletion. Thus, though questions remain as to optimal embryo density and volume of culture media, group embryo culture in the correct culture platform is likely to be superior to individual embryo culture.
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de Sousa e Brito, Clara Sattler. "Biopatenting: “Angst” v. European Harmonization – The ECJ Decision on Stem Cell Patents." European Journal of Risk Regulation 3, no. 1 (2012): 130–34. http://dx.doi.org/10.1017/s1867299x00001938.
Full textAbstract:
Case C-34/10 Brüstle v. Greenpeace1.Article 6(2)(c) of Directive 98/44/EC of the European Parliament and of the Council of 6 July 1998 on the legal protection of biotechnological inventions must be interpreted as meaning that:–any human ovum after fertilisation, any non-fertilised human ovum into which the cell nucleus from a mature human cell has been transplanted, and any non-fertilised human ovum whose division and further development have been stimulated by parthenogenesis constitute a ‘human embryo’;–it is for the referring court to ascertain, in the light of scientific developments, whether a stem cell obtained from a human embryo at the blastocyst stage constitutes a ‘human embryo’ within the meaning of Article 6(2)(c) of Directive 98/44.2.The exclusion from patentability concerning the use of human embryos for industrial or commercial purposes set out in Article 6(2)(c) of Directive 98/44 also covers the use of human embryos for purposes of scientific research, only use for therapeutic or diagnostic purposes which is applied to the human embryo and is useful to it being patentable.3.Article 6(2)(c) of Directive 98/44 excludes an invention from patentability where the technical teaching which is the subject-matter of the patent application requires the prior destruction of human embryos or their use as base material, whatever the stage at which that takes place and even if the description of the technical teaching claimed does not refer to the use of human embryos.
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Eldarov, Chupalav, Alina Gamisonia, Vitaliy Chagovets, et al. "LC-MS Analysis Revealed the Significantly Different Metabolic Profiles in Spent Culture Media of Human Embryos with Distinct Morphology, Karyotype and Implantation Outcomes." International Journal of Molecular Sciences 23, no. 5 (2022): 2706. http://dx.doi.org/10.3390/ijms23052706.
Full textAbstract:
In this study we evaluated possible differences in metabolomic profiles of spent embryo culture media (SECM) of human embryos with distinct morphology, karyotype, and implantation outcomes. A total of 153 samples from embryos of patients undergoing in vitro fertilization (IVF) programs were collected and analyzed by HPLC-MS. Metabolomic profiling and statistical analysis revealed clear clustering of day five SECM from embryos with different morphological classes and karyotype. Profiling of day five SECM from embryos with different implantation outcomes showed 241 significantly changed molecular ions in SECM of successfully implanted embryos. Separate analysis of paired SECM samples on days three and five revealed 46 and 29 molecular signatures respectively, significantly differing in culture media of embryos with a successful outcome. Pathway enrichment analysis suggests certain amino acids, vitamins, and lipid metabolic pathways to be crucial for embryo implantation. Differences between embryos with distinct implantation potential are detectable on the third and fifth day of cultivation that may allow the application of culture medium analysis in different transfer protocols for both fresh and cryopreserved embryos. A combination of traditional morphological criteria with metabolic profiling of SECM may increase implantation rates in assisted reproductive technology programs as well as improve our knowledge of the human embryo metabolism in the early stages of development.
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McLeod, Carolyn, and Françoise Baylis. "Feminists on the Inalienability of Human Embryos." Hypatia 21, no. 1 (2006): 1–14. http://dx.doi.org/10.1111/j.1527-2001.2006.tb00961.x.
Full textAbstract:
The feminist literature against the commodification of embryos in human embryo research includes an argument to the effect that embryos are “intimately connected” to persons, or morally inalienable from them. We explore why embryos might be inalienable to persons and why feminists might find this view appealing. But, ultimately, as feminists, we reject this view because it is inconsistent with full respect for women's reproductive autonomy and with a feminist conception of persons as relational, embodied beings. Overall, feminists should avoid claims about embryos’ being inalienable to persons in arguments for or against the commodification of human embryos.
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Doetschman, Thomas C., Harald Eistetter, Margot Katz, Werner Schmidt, and Rolf Kemler. "The in vitro development of blastocyst-derived embryonic stem cell lines: formation of visceral yolk sac, blood islands and myocardium." Development 87, no. 1 (1985): 27–45. http://dx.doi.org/10.1242/dev.87.1.27.
Full textAbstract:
The in vitro developmental potential of mouse blastocyst-derived embryonic stem cell lines has been investigated. From 3 to 8 days of suspension culture the cells form complex embryoid bodies with endoderm, basal lamina, mesoderm and ectoderm. Many are morphologically similar to embryos of the 6- to 8-day egg-cylinder stage. From 8 to 10 days of culture about half of the embryoid bodies expand into large cystic structures containing alphafoetoprotein and transferrin, thus being analagous to the visceral yolk sac of the postimplantation embryo. Approximately one third of the cystic embryoid bodies develop myocardium and when cultured in the presence of human cord serum, 30 % develop blood islands, thereby exhibiting a high level of organized development at a very high frequency. Furthermore, most embryonic stem cell lines observed exhibit similar characteristics. The in vitro developmental potential of embryonic stem cell lines and the consistency with which the cells express this potential are presented as aspects which open up new approaches to the investigation of embryogenesis.
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Otasevic, Vesna, Lela Surlan, Milica Vucetic, et al. "Expression patterns of mitochondrial OXPHOS components, mitofusin 1 and dynamin-related protein 1 are associated with human embryo fragmentation." Reproduction, Fertility and Development 28, no. 3 (2016): 319. http://dx.doi.org/10.1071/rd13415.
Full textAbstract:
Developmental dysfunction in embryos, such as a lethal level of fragmentation, is assumed to be mitochondrial in origin. This study investigated the molecular basis of mitochondrial impairment in embryo fragmentation. Transcription patterns of factors that determine mitochondrial functionality: (i) components of the oxidative phosphorylation (OXPHOS) – complex I, cytochrome b, complex IV and ATP synthase; (ii) mitochondrial membrane potential (MMP); (iii) mitochondrial DNA (mtDNA) content and (iv) proteins involved in mitochondrial dynamics, mitofusin 1 (Mfn1) and dynamin related protein 1 (Drp1) were examined in six-cells Day 3 non-fragmented (control), low-fragmented (LF) and high-fragmented (HF) human embryos. Gene expression of mitochondria-encoded components of complex I and IV, cytochrome b and mtDNA were increased in HF embryos compared with control and LF embryos. In LF embryos, expression of these molecules was decreased compared with control and HF embryos. Both classes of fragmented embryos had decreased MMP compared with control. LF embryos had increased gene expression of Mfn1 accompanied by decreased expression of Drp1, while HF embryos had decreased Mfn1 expression but increased Drp1 expression. The study revealed that each improper transcriptional (in)activation of mitochondria-encoded components of the OXPHOS during early in vitro embryo development is associated with a decrease in MMP and with embryo fragmentation. The results also showed the importance of mitochondrial dynamics in fragmentation, at least in the extent of this process.
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Kumar, Akash, Kate Im, Milena Banjevic, et al. "Whole-genome risk prediction of common diseases in human preimplantation embryos." Nature Medicine 28, no. 3 (2022): 513–16. http://dx.doi.org/10.1038/s41591-022-01735-0.
Full textAbstract:
AbstractPreimplantation genetic testing (PGT) of in-vitro-fertilized embryos has been proposed as a method to reduce transmission of common disease; however, more comprehensive embryo genetic assessment, combining the effects of common variants and rare variants, remains unavailable. Here, we used a combination of molecular and statistical techniques to reliably infer inherited genome sequence in 110 embryos and model susceptibility across 12 common conditions. We observed a genotype accuracy of 99.0–99.4% at sites relevant to polygenic risk scoring in cases from day-5 embryo biopsies and 97.2–99.1% in cases from day-3 embryo biopsies. Combining rare variants with polygenic risk score (PRS) magnifies predicted differences across sibling embryos. For example, in a couple with a pathogenic BRCA1 variant, we predicted a 15-fold difference in odds ratio (OR) across siblings when combining versus a 4.5-fold or 3-fold difference with BRCA1 or PRS alone. Our findings may inform the discussion of utility and implementation of genome-based PGT in clinical practice.
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Aguilera, C., D. Veraguas, C. Henriquez, A. Velasquez, F. O. Castro, and L. Rodriguez-Alvarez. "80 Evaluation of extracellular vesicles from culture medium of human embryos as a possible method of pre-implantation genetic diagnosis." Reproduction, Fertility and Development 32, no. 2 (2020): 166. http://dx.doi.org/10.1071/rdv32n2ab80.
Full textAbstract:
Noninvasive methods are the clue to increase the efficiency of invitro-derived embryo selection without decreasing their competence. Embryos selection based on their morphology is the most used method but only 40% of selected embryos are able to implant and develop correctly. In humans, pre-implantation genetic diagnosis increases the efficiency of selection by excluding embryos with chromosomal abnormalities. However, pre-implantation genetic diagnosis needs embryonic cells, which might compromise embryo viability. On the other hand, embryos release extracellular vesicles (EVs: microvesicles and exosomes) to the culture medium that contain biological cargo-like proteins and mRNA lipids, and might contain genomic DNA (gDNA). For this study we evaluated the culture medium from embryos generated by intracytoplasmic sperm injection in a certified fertility clinic. Embryos were cultured in Global Total serum-free medium. The embryos were assessed at Day 3 of development and classified in three categories: top, fair, and poor quality. Corresponding medium was collected for isolation of EVs. The nature of EVs was confirmed by their size and concentration using nanoparticle tracking analysis (NTA), presence of surface markers (CD9, CD63, CD81, and CD40L), and morphology using transmission electron microscopy. A correlation analysis between NTA results (EV size and concentration) and embryo quality was performed. To evaluate chromosomal abnormalities of gDNA present in isolated EVs from embryo culture medium, microarray-based comparative genomic hybridization (aCGH) assay was performed. In a second experiment, aCGH analysis was performed and compared between arrested embryos and EVs isolated from corresponding culture medium. Isolated nanoparticles from embryo culture medium were positive to all markers CD9 (30.9%), CD63 (27.2%), CD81 (31.7%), CD40L (8.7%) and had a morphology accordingly to exosomes. The analysis of NTA data indicated that top-quality embryos had EVs with higher diameter (mean: 112.17nm, mode: 91.74nm) than embryos classified as fair (mean: 108.02nm, mode: 89.67nm) and poor quality (mean: 102.78nm, mode: 88.17 nm; P<0.05). The aCGH analysis showed the representation of the 23 pairs of chromosomes in EVs from culture medium and the chromosomal abnormalities were detected in chromosome 4 (C4: 6/15 (40%)) and chromosome 13 (C13: 6/15 (40%)). In the second experiment, the aCGH assay also showed abnormalities in different chromosomes from samples of EVs from culture medium (24.9%) and were more frequent than those observed in the arrested embryos (8.7%; P=0.03). However, the rate of similitude in chromosomal abnormalities between EVs and their respective embryo was 70-80%. In conclusion, the size and gDNA of EVs from culture medium might be an alternative to evaluate the competence of human embryos. This research was supported by FONDECYT-1170310 and Corfo 17Cote-72437, Chile.
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Ain, Rupasri, and P. B. Seshagiri. "Micromolar concentration of pentoxifylline improves development in vitro of hamster 8-cell embryos: conrmation of biological viability by embryo transfer." Reproduction, Fertility and Development 9, no. 7 (1997): 697. http://dx.doi.org/10.1071/r97052.
Full textAbstract:
The inßuence of the sperm motility stimulant pentoxifylline (PF) on preimplantation embryo development in hamsters was evaluated. Eight-cell embryos were cultured in hamster embryo culture medium (HECM)-2, with or without PF (0· 0233·6 mM). There was 90%, 37% and 29% inhibition of blastocyst development by 3·6 (used for human sperm), 0·9 and 0 ·45 mM PF, respectively. However, 23 µM PF (exposed to hamster oocytes during IVF) signicantly (P < 0·05) improved blastocyst development (63· 6% v. 51· 8%); morulae development was, however, not curtailed by 0·45 mM or 0·9 mM PF (51·8%±6·0 or 50·5%±11·3, respectively). Post-implantation viability of PF-treated embryos was assessed by embryo transfer; 43% of 80 PF-treated embryos implanted compared with 40% of 79 control embryos. Of the 9 recipients, 6 females delivered pups (19, i.e. 16% of transferred embryos or 53% of implanted embryos). These data show that in hamsters, continuous presence of PF at 0·45-3·6 mM is detrimental to 8-cell embryo development whereas 23 µM PF improves the development of embryos to viable blastocysts which produce live offspring.
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Kvit, Natalia M., Sibilla B. Buletsa, and Vasyl V. Kopcha. "RESEARCH USE OF HUMAN IN VITRO EMBRYOS: LEGAL BOUNDARIES." Wiadomości Lekarskie 74, no. 11 (2021): 3060–66. http://dx.doi.org/10.36740/wlek202111234.
Full textAbstract:
The aim: The purpose of this research is to study foreign experience in the field of legal regulation of the use of embryos in vitro to suggest ways to fill the gaps in current Ukrainian legislation and bring it into line with international law. Materials and methods: The subject of the research was the legal regulation of the in vitro embryo research use, which is completely outside of the current Ukrainian legislation. That is why the European models of its regulation were analyzed. The experience of Germany and Hungary in the field of in vitro embryo research use regulation was considered as an example and was compared with the current Ukrainian regulation. Conclusion: As the use of non-implanted embryos is outside the legal field, the anatomical materials of a dead embryo, whether implanted or not, can be removed both for scientific research within the statutory framework (subject to approval by the ethics committee) and with the therapeutic purpose (for cell transplantation), subject to the relevant proposed amendments to the legislation to comply with the requirements of the Convention on Human Rights and Biomedicine (Art. 18). Instead, the creation and further use of embryos for any purpose other than reproductive is illegal and should be prohibited by law with the imposition of appropriate criminal penalties. The right to dispose of embryos for research purposes may be granted by the woman and the man for whom the embryo was created, subject to informed consent and personal data processing consent.