Journal articles on the topic 'Fertilisation procedure'
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Metwally, Mostafa, Robin Chatters, Clare Pye, Munya Dimairo, David White, Stephen Walters, Judith Cohen, et al. "Endometrial scratch to increase live birth rates in women undergoing first-time in vitro fertilisation: RCT and systematic review." Health Technology Assessment 26, no. 10 (January 2022): 1–212. http://dx.doi.org/10.3310/jnzt9406.
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Background In vitro fertilisation is a widely used reproductive technique that can be undertaken with or without intracytoplasmic sperm injection. The endometrial scratch procedure is an in vitro fertilisation ‘add-on’ that is sometimes provided prior to the first in vitro fertilisation cycle, but there is a lack of evidence to support its use. Objectives (1) To assess the clinical effectiveness, safety and cost-effectiveness of endometrial scratch compared with treatment as usual in women undergoing their first in vitro fertilisation cycle (the ‘Endometrial Scratch Trial’) and (2) to undertake a systematic review to combine the results of the Endometrial Scratch Trial with those of previous trials in which endometrial scratch was provided prior to the first in vitro fertilisation cycle. Design A pragmatic, multicentre, superiority, open-label, parallel-group, individually randomised controlled trial. Participants were randomised (1 : 1) via a web-based system to receive endometrial scratch or treatment as usual using stratified block randomisation. The systematic review involved searching electronic databases (undertaken in January 2020) and clinicaltrials.gov (undertaken in September 2020) for relevant trials. Setting Sixteen UK fertility units. Participants Women aged 18–37 years, inclusive, undergoing their first in vitro fertilisation cycle. The exclusion criteria included severe endometriosis, body mass index ≥ 35 kg/m2 and previous trauma to the endometrium. Interventions Endometrial scratch was undertaken in the mid-luteal phase of the menstrual cycle prior to in vitro fertilisation, and involved inserting a pipelle into the cavity of the uterus and rotating and withdrawing it three or four times. The endometrial scratch group then received usual in vitro fertilisation treatment. The treatment-as-usual group received usual in vitro fertilisation only. Main outcome measures The primary outcome was live birth after completion of 24 weeks’ gestation within 10.5 months of egg collection. Secondary outcomes included implantation, pregnancy, ectopic pregnancy, miscarriage, pain and tolerability of the procedure, adverse events and treatment costs. Results One thousand and forty-eight (30.3%) women were randomised to treatment as usual (n = 525) or endometrial scratch (n = 523) and were followed up between July 2016 and October 2019 and included in the intention-to-treat analysis. In the endometrial scratch group, 453 (86.6%) women received the endometrial scratch procedure. A total of 494 (94.1%) women in the treatment-as-usual group and 497 (95.0%) women in the endometrial scratch group underwent in vitro fertilisation. The live birth rate was 37.1% (195/525) in the treatment-as-usual group and 38.6% (202/523) in the endometrial scratch group: an unadjusted absolute difference of 1.5% (95% confidence interval –4.4% to 7.4%; p = 0.621). There were no statistically significant differences in secondary outcomes. Safety events were comparable across groups. No neonatal deaths were recorded. The cost per successful live birth was £11.90 per woman (95% confidence interval –£134 to £127). The pooled results of this trial and of eight similar trials found no evidence of a significant effect of endometrial scratch in increasing live birth rate (odds ratio 1.03, 95% confidence interval 0.87 to 1.22). Limitations A sham endometrial scratch procedure was not undertaken, but it is unlikely that doing so would have influenced the results, as objective fertility outcomes were used. A total of 9.2% of women randomised to receive endometrial scratch did not undergo the procedure, which may have slightly diluted the treatment effect. Conclusions We found no evidence to support the theory that performing endometrial scratch in the mid-luteal phase in women undergoing their first in vitro fertilisation cycle significantly improves live birth rate, although the procedure was well tolerated and safe. We recommend that endometrial scratch is not undertaken in this population. Trial registration This trial is registered as ISRCTN23800982. Funding This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 10. See the NIHR Journals Library website for further project information.
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Daily, Michael F., Virginia H. Latham, Claudia M. Garcia, Cynthia L. Hockman, Helen Chun, Mark L. Oppenheimer, Steven P. West, et al. "Producing exposed cota-free embryos." Zygote 2, no. 3 (August 1994): 221–25. http://dx.doi.org/10.1017/s096719940000201x.
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SummaryProduction of embryos that are free of tough outer coats facilitates studies that are not possible with embryos surrounded by impenetrable envelopes. This report describes a new procedure for preventing formation of fertilisation membranes in the sea urchin (Lytechinus pictus) model. This procedure involves treating unfertilised eggs with the enzyme alpha-amylase, which cleaves alpha-1,4 glucosidic bonds in the vitelline layer. A major advantage of this method is that it is very well defined and completely controllable with alpha-amylase inhibitor. The results suggest that intact alpha-1,4 glucosidic bonds are essential for vitelline layer integrity required for formation of the fertilisation membrane. Eggs treated with alpha-amylase possessed the same surface lectin receptors as untreated eggs and, as shown by light and transmission electron microscopy, produced healthy, cleaving embryos that were free of fertilisation envelopes.
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Matłok, Natalia, Oskar Basara, Miłosz Zardzewiały, Józef Gorzelany, and Maciej Balawejder. "Effectiveness of a Complex Fertilisation Technology Applied to Zea mays, Assessed Based on Normalised Difference Vegetation Index (NDVI) from Terra Moderate Resolution Imaging Spectroradiometer (MODIS)." Agriculture 11, no. 8 (August 8, 2021): 754. http://dx.doi.org/10.3390/agriculture11080754.
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Assessment of effectiveness of fertilisation is a complex, multistage procedure. A few methods, used for this purpose, are based mainly on physiological measures acquired from a limited number of plants. Assessment of the process taking into account the entire area, in which the crop is grown, can be conducted using satellite remote sensing methods. The current study presents four fertilisation schemes applied to maize plants, including innovative foliar fertilizers and soil localized fertilization. Nutritional status and condition of the plants were assessed using Normalized Difference Vegetation Index (NDVI), and the results were analysed in relation to the grain yield. The findings show that the complex fertilisation technology applied to maize is most effective, producing grain yield which was 42.4% higher than the yield from the control variant.
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Chen, Juan, Yun Qian, Yong Tan, and Hirofumi Mima. "Successful pregnancy following oocyte activation by strontium in normozoospermic patients of unexplained infertility with fertilisation failures during previous intracytoplasmic sperm injection treatment." Reproduction, Fertility and Development 22, no. 5 (2010): 852. http://dx.doi.org/10.1071/rd09268.
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Fertilisation failures occur in 2–3% of intracytoplasmic sperm injection (ICSI) cycles and are mostly caused by failure of oocyte activation. Assisted oocyte activation (AOA) may be an efficient treatment option to overcome oocyte activation failure. To evaluate the effectiveness of ICSI combined with AOA by strontium, six couples with complete fertilisation failure or low fertilisation rates (ranging from 0% to 16.7%; mean = 7.7%) in previous ICSI cycles were involved in the present study. In the latest ICSI cycles, AOA by strontium treatment was combined with ICSI to improve clinical outcomes. Fifty-two mature oocytes retrieved from six females were stimulated by strontium treatment after ICSI procedure, and 41 (78.8%) of them were successfully fertilised. The high-quality embryo rate was 41.5% (17/41) after culture for 5 days. Thirteen embryos were transferred (ranging from 2 to 3 per individual) resulting in three clinical pregnancies and three healthy babies were born. Furthermore, a pregnancy resulting in the birth of a healthy female infant was achieved following transfer of three frozen–thawed embryos. In conclusion, it appears that strontium treatment would be an effective method for AOA to improve fertilisation rates and embryo quality in cases with fertilisation failure after ICSI.
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Nel, A. A., and A. A. Bloem. "The delta yield procedure for nitrogen fertilisation of maize in South Africa." South African Journal of Plant and Soil 23, no. 3 (January 2006): 203–8. http://dx.doi.org/10.1080/02571862.2006.10634755.
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Malo, Clara, Lydia Gil, Rafael Cano, Felisa Martinez, and Noelia Gonzalez. "Progesterone improves porcine in vitro fertilisation system." Acta Veterinaria Hungarica 62, no. 1 (March 1, 2014): 117–24. http://dx.doi.org/10.1556/avet.2013.048.
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In an effort to improve the quality of in vitro produced porcine embryos, the effect of progestagens — progesterone analogues — on the in vitro developmental competence of porcine oocytes was studied. A total of 1421 in vitro matured oocytes, from 4 replicates, were inseminated with frozen-thawed spermatozoa. Progestagens were added to late maturation and embryo cultures (10 IU/ml). Fertilisation success (pre-maturation, penetration, monospermy and efficiency) and nuclear maturation were evaluated. There were no differences among prematuration rates between groups (P = 0.221). Penetration rates were higher (P < 0.001) in the presence of progestagens (75.0%) as compared to the control (51.7%). However, no differences were observed in monospermy percentages (P = 0.246). The results indicated that supplementation with progestagens increased the efficiency of the in vitro fertilisation system (P < 0.001). An additional beneficial effect was observed in nuclear maturation with progestagens (P = 0.035). In summary, progestagen supplementation is an important factor to improve the in vitro fertilisation procedure.
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Zörb, Christian, Dorothee Steinfurth, Victoria Gödde, Karsten Niehaus, and Karl H. Mühling. "Metabolite profiling of wheat flag leaf and grains during grain filling phase as affected by sulfur fertilisation." Functional Plant Biology 39, no. 2 (2012): 156. http://dx.doi.org/10.1071/fp11158.
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Increasing prices for wheat products and fertilisers call for an adjusted agricultural management to maintain yield and to improve product quality. With the increased use of sulfur-free fertilisers in modern cropping systems and the decrease of atmospheric sulfur emissions by industry, sulfur has become a major limiting factor for crop production. The presented data showed that by using GC-MS it was possible to quantitatively detect a set of 72 different metabolites including amino acids, organic acids, sugars, sugar phosphates, and sugar alcohols, phenolic compounds and nucleotides from wheat grains and flag leaves of a pot experiment. A principal component analysis (PCA) revealed a clear separation of flag leaves and grains and a clear separation of non-fertilised and fertilised flag leaves. It could further be shown by PCA, that the low level sulfur fertilisation is also separated from the higher fertilised grains. A considerable influence of the sulfur fertilisation not only on sulfur rich amino acids but also on the sugar metabolism was detected. With increasing sulfur fertilisation six sugars and sugar derivates in the grain such as glucose-6P, galactose, trehalose, cellobiose, melibiose, fumarate, glycerate and the nucleotide uracil were enhanced. Therefore, it was concluded that photosynthesis was limited in developing plants suffering from sulfur deficiency. Late sulfur fertilisation is a procedure that can help to prevent sulfur deficiency. A latent sulfur deficiency at ear emergence can be compensated by late sulfur fertilisation, as wheat plants can replenish sulfate deficits within a short time.
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Song, Y. P., M. Suquet, I. Quéau, and L. Lebrun. "Setting of a procedure for experimental fertilisation of Pacific oyster (Crassostrea gigas) oocytes." Aquaculture 287, no. 3-4 (February 2009): 311–14. http://dx.doi.org/10.1016/j.aquaculture.2008.10.018.
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Stephenson, J. L., and B. G. Brackett. "Influences of zinc on fertilisation and development of bovine oocytes in vitro." Zygote 7, no. 3 (August 1999): 195–201. http://dx.doi.org/10.1017/s096719949900057x.
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The effects of zinc (as ZnCl2) on in vitro production of bovine embryos (IVMFC) and components of the procedure, that is in vitro oocyte maturation (IVM), fertilisation (IVF) and embryo development in culture (IVC), and the effect of added zinc on sperm motility were studied. Immature cumulus oocyte complexes (COCs) were aspirated from ovarian follicles (2-5 mm diameter) at slaughter, and matured, fertilised and cultured in chemically defined conditions. The presence of zinc (10, 100 or 1000 μg added per millilitre) throughout IVMFC inhibited fertilisation. After addition of 10 μg zinc per millilitre separately to media for IVM and IVF, fertilisation was inhibited only when zinc was present for IVM. When present for IVF, 80% of oocytes selected for IVM reached 2- to 4-cell stages by 46 h after insemination whereas 67% of control oocytes (inseminated without added zinc) cleaved. Higher zinc concentrations (100 and 1000 μg added per millilitre) for IVF inhibited fertilisation. Sperm motility was reduced with addition of 10 μg per millilitre of zinc for sperm preparation (i.e. capacitation interval). Addition of 1.0 μg zinc per millilitre to media used through IVMFC, or to the IVC medium alone, resulted in inhibition of development after 2- to 4-cell stages. When added to IVM or to both IVM and IVF media 1.0 μg/ml of zinc compromised development to the morula stage and beyond. Maturing bovine oocytes may be more sensitive to 1.0 μg ml of zinc in vitro than in vivo because a concentration of 3.0 μg/ml has been reported for bovine follicular fluid. Fertilisation was not adversely affected by 10 μg/ml of zinc; however, higher concentrations were inhibitory.
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Jordan, Bertrand. "Scores polygéniques : vers l’embryon à la carte ?" médecine/sciences 36, no. 3 (March 2020): 289–91. http://dx.doi.org/10.1051/medsci/2020028.
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A new company is offering extensive genetic analysis of embryos during an in vitro fertilisation procedure, allowing the derivation of polygenic scores for several diseases and embryo choice based on these results. Polygenic scores, if properly implemented, can indeed have substantial predictive value, and the possibility of embryo choice based on these data has become real, raising a number of practical and ethical problems. ‡
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Sood, Aradhana, Suvash Sahu, Sandeep Karunakaran, Rajneesh K. Joshi, and Deep Kumar Raman. "Dermatological Manifestations in Patients Undergoing In Vitro Fertilisation: A Prospective Study." Journal of Cutaneous Medicine and Surgery 22, no. 3 (January 13, 2018): 280–84. http://dx.doi.org/10.1177/1203475417752370.
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Background: Changing sociodemographic patterns with an increase in the age of childbirth have affected fertility rates worldwide. With advancing reproductive medicine, assisted reproductive techniques (ARTs) are becoming common. While dermatological manifestations in normal pregnancies have been well documented, there is a paucity of data regarding cutaneous manifestations in patients undergoing ART. Objectives: The objectives of our study were to estimate the incidence and types of dermatological manifestations in patients undergoing in vitro fertilisation (IVF) and to study their associations with age, type of infertility, and outcome of the procedure. Methods: A prospective cohort of 200 patients undergoing IVF in a tertiary care centre was observed for occurrence of any dermatological manifestations from initiation of the IVF protocol to the outcome of the procedure at 3 weeks after embryo transfer. Results: Dermatological manifestations were seen in 27% of the study group, with urticaria being the most common cutaneous finding seen in 13.5%, followed by acneform eruptions (3%). Twenty-six (96.3%) of patients who manifested with urticaria were on progesterone. No statistically significant association was found between the occurrence of dermatological manifestations and the outcome of IVF, type of infertility, history of ART, and ovum donation in our study. Association between the age of the patient and the outcome of IVF cycle was statistically significant. Conclusion: Dermatological manifestations are seen in almost one-quarter of patients undergoing IVF, with progesterone-induced urticaria being the most common. Occurrence of cutaneous manifestations has no significant association with the outcome of IVF.
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Bingel, Daniel D. "An Ethical Examination of the Challenges of In Vitro Fertilisation in Nigeria." International Letters of Social and Humanistic Sciences 14 (October 2013): 20–25. http://dx.doi.org/10.18052/www.scipress.com/ilshs.14.20.
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It is the position of this paper that the availability of In-Vitro Fertilisation (IVF) treatment clinics in Nigeria‟s healthcare system has moral implications which are as yet not fully considered nor critically understudied. The paper argues that the availability of such procedures ought to be properly considered and the many ramifications it may have to individuals as well as to national values be comprehensively examined at this early stage before it becomes widespread so as to preserve both our national values and the good of the individual citizen. It proceeds by identifying the need for Nigeria as a country to dedicate resources for research based innovations; it also examines the practice of IVF in Nigeria highlighting history, procedure and accessibility. The paper then proceeds to discuss some challenges of IVF in Nigeria before arguing that there are moral objections to IVF that call for national discussion at an early stage. It concludes that IVF has the potential to change the values of Nigerians and it would be wise if these values change consciously rather than unconsciously
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Hagger, Lynn. "The Role of the Human Fertilisation and Embryology Authority." Medical Law International 3, no. 1 (September 1997): 1–22. http://dx.doi.org/10.1177/096853329700300101.
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The recent publicity surrounding Diane Blood and the theoretical possibility of cloning human beings has highlighted yet again the important role of the Human Fertilisation and Embryology Authority (HFEA). It will be remembered that Mrs Blood sought to establish a right to be inseminated with her dead husband's sperm without his written consent. The HFEA, following the strict letter of the Human Fertilisation and Embryology Act 1990, withheld its permission for the procedure. Following a Court of Appeal decision to allow Mrs Blood access to treatment abroad the Department of Health commissioned an independent ethicist to address the relevant issues. The use of such an expert which avoids any potential conflicts of interest, when the body has many members with the relevant expertise, is another example of how important the HFEA's integrity is viewed. It strives to act in an exemplary manner in the often hostile environment of uninformed public concern and against a backdrop of a statutory framework that is generally thought to suffer from a democratic deficit. This article will provide an outline of the HFEA's background, structure and manner of operation in an attempt to demonstrate that it offers a model of regulation for the new reproductive technologies despite the constraints it faces.
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Xhelili, Malbora, Sokrat Xhaxho, Eti Muharremi, and Jera Kruja. "Double risk: Stroke in a patient after in vitro fertilisation (IVT) procedure and foramen ovale apertum." Journal of the Neurological Sciences 429 (October 2021): 119642. http://dx.doi.org/10.1016/j.jns.2021.119642.
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MacKellar, Calum. "Can Maternal Spindle Transfer and Pronuclear Transfer Be Prohibited under eu Legislation?" European Journal of Health Law 25, no. 1 (December 11, 2018): 57–74. http://dx.doi.org/10.1163/15718093-12460338.
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Abstract The question whether maternal spindle transfer (mst) and pronuclear transfer (pnt) can be prohibited under eu legislation was examined by the non-governmental organisation European Bioethics Research (ebr). It did so by submitting an official complaint to the eu Commission proposing that the uk Human Fertilisation and Embryology (Mitochondrial Donation) Regulations 2015 breached the prohibition on the modification of a person’s germ line genetic identity of the eu Clinical Trials Directive 2001/20/EC and the new Regulation eu 536/2014. A discussion then took place, during 2016, between ebr and the eu Commission whether mst and pnt principally involved a ‘medicinal product’ in which case the eu Clinical Trials Directive 2001/20/EC and Regulation eu 536/2014 would be applicable or whether the procedures just involved a medical procedure in which case the Tissue and Cells Directive 2004/23/EC was applicable which did not include any prohibition on the intentional modification of a person’s germline.
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Fernandez-Gonzalez, Lorena, Valeria Kozhevnikova, Eugeny Brusentsev, Stefanie Jänsch, Sergei Amstislavsky, and Katarina Jewgenow. "IGF-I Medium Supplementation Improves Singly Cultured Cat Oocyte Maturation and Embryo Development In Vitro." Animals 11, no. 7 (June 27, 2021): 1909. http://dx.doi.org/10.3390/ani11071909.
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Embryo production is a routine procedure in several species. However, in felids, the effectiveness of this approach is far behind that in the majority of laboratory species. The development of a suitable environment starts with the proper composition of culture media. Therefore, for the improvement of assisted reproduction techniques and their outcome in cats, this is an urgent task. As the addition of insulin-like growth factors (IGF-I, IGF-II) or granulocyte-macrophage colony-stimulating factor (GM-CSF) was beneficial in other mammalian species, this study aims to check whether these components, combined with other factors (such as type of fertilisation or type of culture) can provide a benefit in the felid culture system in current use. Thus, these supplements, in different concentrations and combinations, were merged with the use of two fertilisation techniques and randomly assigned to single or group culturing. The results showed that the addition of IGF-I and/or GM-CSF produced an increase in morula and blastocyst rate in a single culture system. In particular, the supplementation with 20 ng/mL of IGF-I incremented the maturation rate by 10% and significantly increased the morula and blastocyst rates in single culturing. This result is especially remarkable for wild felids, where only a few oocytes and/or embryos are available.
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McLennan, Hanna J., Melanie L. Sutton-McDowall, Sabrina Heng, Andrew D. Abell, and Jeremy G. Thompson. "Time-lapse confocal imaging-induced calcium ion discharge from the cumulus–oocyte complex at the time of cattle oocyte activation." Reproduction, Fertility and Development 32, no. 14 (2020): 1223. http://dx.doi.org/10.1071/rd20143.
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Oocyte activation, the dynamic transformation of an oocyte into an embryo, is largely driven by Ca2+ oscillations that vary in duration and amplitude across species. Previous studies have analysed intraoocyte Ca2+ oscillations in the absence of the oocyte’s supporting cumulus cells. Therefore, it is unknown whether cumulus cells also produce an ionic signal that reflects fertilisation success. Time-lapse confocal microscopy and image analysis on abattoir-derived cattle cumulus–oocyte complexes coincubated with spermatozoa revealed a distinct discharge of fluorescence from the cumulus vestment. This study demonstrated that this Ca2+ fluorescence discharge was an artefact induced by the imaging procedure independently of oocyte activation success. The fluorescence discharge was a direct result of cumulus cell membrane integrity loss, and future studies should consider the long-term effect of fluorescent labels on cells in time-lapse imaging. However, this study also demonstrated that the distinctive pattern of a coordinated fluorescence discharge was associated with both the presence of spermatozoa and subsequent embryo development to the morula stage, which was affected by Ca2+ chelation and a reduction in the active efflux of the fluorophore. This indicates that the cumulus vestment may have a relationship with oocyte activation at and beyond fertilisation that requires further investigation.
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Harper, Joyce C. "Preimplantation genetic screening." Journal of Medical Screening 25, no. 1 (June 14, 2017): 1–5. http://dx.doi.org/10.1177/0969141317691797.
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Preimplantation genetic diagnosis was first successfully performed in 1989 as an alternative to prenatal diagnosis for couples at risk of transmitting a genetic or chromosomal abnormality, such as cystic fibrosis, to their child. From embryos generated in vitro, biopsied cells are genetically tested. From the mid-1990s, this technology has been employed as an embryo selection tool for patients undergoing in vitro fertilisation, screening as many chromosomes as possible, in the hope that selecting chromosomally normal embryos will lead to higher implantation and decreased miscarriage rates. This procedure, preimplantation genetic screening, was initially performed using fluorescent in situ hybridisation, but 11 randomised controlled trials of screening using this technique showed no improvement in in vitro fertilisation delivery rates. Progress in genetic testing has led to the introduction of array comparative genomic hybridisation, quantitative polymerase chain reaction, and next generation sequencing for preimplantation genetic screening, and three small randomised controlled trials of preimplantation genetic screening using these new techniques indicate a modest benefit. Other trials are still in progress but, regardless of their results, preimplantation genetic screening is now being offered globally. In the near future, it is likely that sequencing will be used to screen the full genetic code of the embryo.
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Krishna, Murali, Kapil Chaudhary, and Aditya Prakash Sharma. "Primary bladder neck obstruction in female: ‘an enigmatic disorder’." BMJ Case Reports 15, no. 4 (April 2022): e248851. http://dx.doi.org/10.1136/bcr-2022-248851.
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A 36-year-old woman presented with problems of lower urinary tract symptoms for 2 years duration. Patient was being managed as a case of urethral stricture with routine calibration. Micturating cystourethrogram showed failure of bladder neck to open. On urodynamic study, she was found to have bladder outlet obstruction with high pressure, low flow pattern. Based on these findings, patient was diagnosed to have primary bladder neck obstruction (PBNO). She was also being evaluated for primary infertility and was to undergo in vitro fertilisation. She successfully underwent bladder neck incision after discussion about management options. Bladder neck incision is one of the accepted management options for PBNO. Post procedure patient was relieved of symptoms and also had an uneventful full-term pregnancy. Bladder neck incision in women is an effective treatment option when patient has been properly selected and procedure done with expert hands.
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Keck, G., N. Reichel, A. Zimmermann, I. Trinkaus, A. Schultz, and W. Distler. "291. Potential role of Glycodelin for fertilization success in ART." Reproduction, Fertility and Development 17, no. 9 (2005): 123. http://dx.doi.org/10.1071/srb05abs291.
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Background: Glycodelin (Gd), a dimeric glycoprotein, appears in the female and male reproductive tract in isoforms like GdA from amniotic fluid and endometrium, GdF from follicular fluid, GdS from seminal plasma and on sperm surface as well. Little is known about the role of Gd in IVF. The aim of our study was to investigate the influence of the Gd-amount in supernatants of IVF-cultures to fertilization success. Methods: Employing monoclonal antibody (mAb) M4f8 soluble Gd levels were evaluated by an enzyme-linked immunosorbent assay (ELISA). We assayed 107 supernatants after 18 h in-vitro fertilisation of single cultured oocytes (S18) with 100000 motile spermatozoa derived from 11 couples undergoing conventional IVF procedure. The results have been compared to blanks comprised of sperm suspensions incubated without any oocytes. The Gd-content in S18 were correlated to fertilization success and characterized by PN-scoring 18 h after insemination. Furthermore we evaluated supernatants (n = 21) of oocytes after ICSI. Total protein (TP) of all supernatants was assessed for calculating the Gd/TP-ratio. Results: The soluble Gd values were calculated for the cultures belonging to each couple. The levels of Gd differed interindividually by a wide range from 4.9 up to 69.2 ng/mL (0.1–3.0% Gd/TP) and in the blanks 2.0–59.5 ng/mL (0.1–4.5% Gd/TP) as well. We associated a couple specific Gd level from 10.0–60.0 ng/mL with a high fertilisation rate (FR = 88%). Both a soluble Gd at a lower level in sperm–oocyte suspensions and a S18 > 60.0 ng/mL were accompanied by a decreased FR (25%). The supernatants (n = 21) after ICSI (FR = 14%) were found Gd-free. Conclusions: Gd-amounts in S18 fluctuated both between the different patients and within their individual sperm–egg cultures. Therefore the protein is suggested not being introduced by spermatozoa only but rather by cumulus cell effects. Beside other parameters one of the fertilisation-dependant factors may be the patient-specific Gd concentration in the surrounding medium.
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Li, Dun-Gao, Yan Zhu, Feng-Ying Xing, Shan-Gang Li, Xue-Jin Chen, and Man-Xi Jiang. "Microtubule organisation, pronuclear formation and embryonic development of mouse oocytes after intracytoplasmic sperm injection or parthenogenetic activation and then slow-freezing with 1,2-propanediol." Reproduction, Fertility and Development 25, no. 4 (2013): 609. http://dx.doi.org/10.1071/rd12124.
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The goal of this study was to investigate the effect of cryopreservation on oocytes at different times after intracytoplasmic sperm injection (ICSI) and parthenogenetic activation. The study was performed in mouse oocytes fertilised by ICSI, or in artificially-activated oocytes, which were cryopreserved immediately, one hour or five hours later through slow-freezing. After thawing, the rates of survival, fertilisation–activation, embryonic development of oocytes–zygotes and changes in the cytoskeleton and ploidy were observed. Our results reveal a significant difference in survival rates of 0-, 1- and 5-h cryopreserved oocytes following ICSI and artificial activation. Moreover, significant differences in two pronuclei (PN) development existed between the 0-, 1- and 5-h groups of oocytes frozen after ICSI, while the rates of two-PN development of activated oocytes were different between the 1-h and 5-h groups. Despite these initial differences, there was no difference in the rate of blastocyst formation from two-PN zygotes following ICSI or artificial activation. However, compared with ICSI or artificially-activated oocytes cryopreserved at 5 h, many oocytes from the 0- and 1-h cryopreservation groups developed to zygotes with abnormal ploidy; this suggests that too little time before cryopreservation can result in some activated oocytes forming abnormal ploidy. However, our results also demonstrate that spermatozoa can maintain normal fertilisation capacity in frozen ICSI oocytes and the procedure of freeze–thawing did not affect the later development of zygotes.
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Pessina, Domenico, Davide Facchinetti, Javier Tardaguila, Isabella Ghiglieno, and Leonardo Valenti. "Mechanical behaviour of three organic fertilisers to optimise spreading methods in the vineyard." RIVISTA DI STUDI SULLA SOSTENIBILITA', no. 2 (January 2020): 375–90. http://dx.doi.org/10.3280/riss2019-002-s1024.
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Organic viticulture is attracting increasing interest worldwide. Fertilisation can be carried out with different products, such as manure, the solid fraction of digestate and compost. In order to optimise the distribution rate, it is very important to previously check the physical characteristics of these materials, which are typically subjected to progressive compression during the spreading procedure. In this context, the use of dedicated sensors and specialised software devoted to piloting the rotors and bulkhead speed of the spreader is highly recommended, taking into account also the different rheological characteristics of the different matrices. A series of laboratory tests to determine the load-deformation curve were arranged. The results showed that digestate and manure behaved in a similar way, but the former was more compact with the same load.
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Stoops, Monica A., Jennifer B. Bond, Helen L. Bateman, Mark K. Campbell, Gregory P. Levens, Todd R. Bowsher, Shannon T. Ferrell, and William F. Swanson. "Comparison of different sperm cryopreservation procedures on post-thaw quality and heterologous in vitro fertilisation success in the ocelot (Leopardus pardalis)." Reproduction, Fertility and Development 19, no. 5 (2007): 685. http://dx.doi.org/10.1071/rd06078.
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Cryopreservation of spermatozoa from free-living ocelots (Leopardus pardalis) could benefit their conservation by facilitating gene flow between in situ and ex situ populations without requiring removal of additional cats from the wild. The objective of this study was to investigate three different methods of ocelot sperm cryopreservation to identify the most appropriate technique for use in a field environment. Male ocelots (n = 10), housed in North American zoos, were anaesthetised with tiletamine–zolazepam (7mg kg–1 bodyweight; i.m.) and subjected to a regimented electroejaculation procedure. Recovered semen was evaluated for sperm concentration, motility and morphology and processed for cryopreservation by three methods: (1) pelleting on dry ice, (2) freezing in straws over liquid nitrogen vapour; and (3) freezing in straws in a dry shipper. Frozen samples were thawed and assessed for post-thaw acrosome status, viability, motility over time and ability to fertilise viable domestic cat oocytes. Although several post-thaw sperm parameters varied (P < 0.05) among freezing methods, frozen–thawed ocelot spermatozoa from all treatments showed a similar (P > 0.05) capacity to bind, penetrate and fertilise viable domestic cat oocytes. These findings suggest that spermatozoa collected from male ocelots under field conditions may be frozen in straws either using liquid nitrogen alone or in a charged dry shipper to retain adequate functional competence after thawing for use with assisted reproductive procedures.
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Garalejic, Eliana, Biljana Arsic, Dragana Bojovic-Jovic, Milija Veljkovic, Biljana Macanovic, Dejan Pavlovic, Bojan Vasic, and Dragana Lekic. "Woman with surgical reconstruction of anal atresia who realized pregnancy with in vitro fertilisation." Vojnosanitetski pregled 67, no. 3 (2010): 249–51. http://dx.doi.org/10.2298/vsp1003249g.
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Introduction. Anal atresia is a congenital anomaly, very life threatening and urgent. Surgical treatment of this anomaly consists of colostomy first, and then of anal reconstruction. Case report. We presented a 31-year old female with the surgery treatment of anal atresia in the early childhood. In the reproductive period, due to tubal infertily, the patient was included in the program of in vitro fertilization (IVF), in the Clinic for Gynecology and Obstetrics 'Narodni front', Belgrade. Within this program a long protocol of ovarian stimulation was performed. Ultrasonographic and color Doppler monitoring of the patient was applied by the use of an ultrasonographic apparatus type Siemens Acuson X 150, while any hormonal examinations were performed by an Architect Abbott unit. During the IVF program, the growth of follicules was controlled by the use of ultrasonography, microcirculation of the ovaries and the uterus was marked by a power-pulsating color Doppler, and hormonal examination was performed starting from the day of stimulation up to the day of injecting Pregnyl?. The patient was administered Suprefact? (buserelin) sc from the 21st day of the menstrual cycle, as well as from the 3rd day of the cycle, for totally 11 days. The patient was given 29 ampoules of Gonal F? (recombinant human FSH) 75 IJ im and 15 ampoules of Menopur? (menotrophin) im. Due to a modified pelvic anatomy, the left ovary aspiration was disabled, while the right ovary aspired seven oocytes successfully. Three embryos were inserted in the uterus. The delivery was performed by cesarean section. Conclusion. In the reported patient with a modified pelvic anatomy due to four corrective surgeries of anal atresia, and tubal infertility in the reproductive period, the method of choice for the realization of pregnancy was the IVF procedure. The realized pregnancy and the delivery could be considered highly successful in regard to possible risks.
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Varga, Erika, J. C. Gardón, and Ágnes Bali Papp. "Effect of open pulled straw (ops) vitrification on the fertilisation rate and developmental competence of porcine oocytes." Acta Veterinaria Hungarica 54, no. 1 (January 1, 2006): 107–16. http://dx.doi.org/10.1556/avet.54.2006.1.11.
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Freezing technologies are very important to preserve gametes and embryos of animals with a good pedigree or those having high genetic value. The aim of this work was to compare immature and in vitromatured porcine oocytes regarding their morphology and ability to be fertilised after vitrification by the open pulled straw (OPS) method. In four experiments 830 oocytes were examined. To investigate the effect of cumulus cells on oocyte survival after OPS vitrification, both denuded and cumulus-enclosed oocytes were vitrified at the germinal vesicle (GV) stage, then after vitrification they were matured in vitro. Besides, in vitromatured oocytes surrounded with a cumulus and those without a cumulus were also vitrified. The survival of oocytes was evaluated by their morphology. After in vitrofertilisation the rates of oocytes penetrated by spermatozoa were compared. Our results suggest that the vitrification/warming procedure is the most effective in cumulus-enclosed oocytes (22.35 ± 1.75%). There was no difference between the order of maturation and vitrification in cumulus-enclosed oocytes, which suggests the importance of cumulus cells in protecting the viability of oocytes during cryopreservation.
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Yesiladali, Mert, Erdinc Saridogan, and Ertan Saridogan. "Successful pregnancy and delivery following surgical treatment of postmyomectomy uterocutaneous fistula." BMJ Case Reports 12, no. 12 (December 2019): e231594. http://dx.doi.org/10.1136/bcr-2019-231594.
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Uterocutaneous fistula is an extremely rare clinical condition that may be caused by postoperative or postpartum complications, such as infection or inflammation. Although fibroids and myomectomy are common clinical entities among women of reproductive age, there are very few postmyomectomy uterocutaneous fistula cases in the literature. This article presents the first reported case of a succesful pregnancy and live birth following treatment of a postmyomectomy uterocutaneous fistula. After laparoscopic adhesiolysis, a minilaparotomy was performed to excise the fistula tract completely from both the abdominal wall and the uterus. The uterine wall defect was repaired in multiple layers. The patient had a good recovery after surgery, and the uterocutaneous fistula resolved completely. Due to obliteration of both tubal ostia, the patient was referred for in vitro fertilisation treatment. She conceived after the third frozen embryo transfer procedure and gave birth to a 4.4 kg baby at full term by caesarean section.
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Clarke, G. N., D. Y. Liu, and H. W. G. Baker. "Improved sperm cryopreservation using cold cryoprotectant." Reproduction, Fertility and Development 15, no. 7 (2003): 377. http://dx.doi.org/10.1071/rd03007.
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It has generally been assumed that very rapid cooling above freezing point would be deleterious to human sperm because it would result in cold shock. Consequently, most routine cryopreservation protocols involve the use of warm (20–30°C) cryoprotectant and slow cooling above the freezing point in order to minimise the risk of cold shock. In order to test this assumption, we added an equal volume of cold (4°C) cryoprotectant in a single aliquot to warm (20, 30 or 37°C) semen to induce rapid cooling. The results of this procedure were compared with those obtained using warm cryoprotectant or with the routine cryopreservation protocol used in this laboratory. The use of cold cryoprotectant resulted in a significant (P = 0.016) improvement (mean 63%, range 42%–79%) in post-thaw motility recovery compared with a standard procedure(mean 47%, range 35%–67%) and a significant (P = 0.016) improvement in post-thaw sperm velocity. A cold glycerol/egg yolk/citrate (GEYC) mixture also gave significantly higher motility recovery than GEYC equilibrated to either room temperature (20°C) or body temperature (37°C). Sperm frozen using the cold cryoprotectant protocol were as efficient at binding to and penetrating the human zona pellucida as sperm frozen with a standard protocol.The modified cryopreservation procedure may lead to improved pregnancy rates in donor insemination and in vitro fertilisation. Further investigation is required to determine how the cold cryoprotectant improves the cryopreservation outcome.
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MAGUIRE, ABIGAIL. "An Examination into the Embryo Disposal Practices of Human Fertilization and Embryology Authority Licenced Fertility Centers in the United Kingdom." Cambridge Quarterly of Healthcare Ethics 30, no. 1 (December 29, 2020): 161–74. http://dx.doi.org/10.1017/s096318012000064x.
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AbstractWhen fertility centers dispose of embryos, how should this be done? Current regulatory guidelines by the Human Fertilisation and Embryology Authority state that, when terminating the development of human embryos, a clinic should act with sensitivity, taking account of the embryo’s “special status” and respecting the interests of the gamete providers and recipients. As yet, it is unclear as to how and to what extent this achieved within fertility clinics in the UK. Resultantly, this paper examines the largely undocumented domain of embryo disposal practice. By undertaking an empirical study into policy and procedure and noting divergence in clinic practice, it then comments on the ethical implications of these protocols for patients and practitioners. Specifically, this paper argues for a more holistic approach to embryo disposal. An approach that effectively meets the requirements of the lab, is respectful of the “special status” of the human embryo, and, perhaps most importantly, reflects the multifaceted needs of the patient.
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Adamczak, Rafał, Natalia Ukleja-Sokołowska, Kinga Lis, and Mariusz Dubiel. "Function of Follicular Cytokines: Roles Played during Maturation, Development and Implantation of Embryo." Medicina 57, no. 11 (November 16, 2021): 1251. http://dx.doi.org/10.3390/medicina57111251.
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A balance within the immune system is necessary for the proper development of ovarian follicles. Numerous cytokines were detected in follicular fluid, the role of which in reproductive physiology seems crucial. They influence the development and maturation of the follicle, ovulation, and corpus luteum formation, as well as embryo implantation and maintenance of pregnancy. The analysis of follicular fluid requires its collection by puncturing of the ovary, which is usually executed in connection with various gynaecological procedures. When interpreting such test results, clinical indications for a given procedure and the method of patient preparation should be taken into account. This review revealed the results of currently available studies on the concentration of pro-inflammatory cytokines in follicular fluid in various forms of infertility. Additionally, it presented cytokines, whose concentration has a significant impact on the size of ovarian follicles, their number, the effectiveness of in vitro fertilisation, development of the embryo, and chances of correct implantation. Despite the many recent publications, the knowledge of follicular fluid immunology in the context of reproductive pathology is superficial and further research is required to extensively understand the roles of individual cytokines in reproductive pathology. In the future, this knowledge may enable patients’ individual qualifications to individual methods of infertility treatment, as well as the possible adjustment of the treatment regimen to the patient’s immune profile.
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Zheng, Xiaoying, Wei Guo, Lin Zeng, Danni Zheng, Shuo Yang, Lina Wang, Rui Wang, Ben W. Mol, Rong Li, and Jie Qiao. "Live birth after in vitro maturation versus standard in vitro fertilisation for women with polycystic ovary syndrome: protocol for a non-inferiority randomised clinical trial." BMJ Open 10, no. 4 (April 2020): e035334. http://dx.doi.org/10.1136/bmjopen-2019-035334.
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IntroductionPolycystic ovary syndrome (PCOS) is the first common cause of anovulatory infertility. Currently, in vitro fertilisation (IVF) is recommended when conventional attempts have failed. In vitro maturation (IVM) of human oocytes is an emerging treatment option in infertile women with PCOS. It is a patient-friendly intervention, avoiding the risk of ovarian hyperstimulation syndrome, which is a serious complication of controlled ovarian stimulation in the standard IVF procedure. We plan a randomised controlled trial (RCT) to evaluate whether IVM is non-inferior to the standard IVF for live birth in women with PCOS.Methods and analysisThis is a single-centre, open-label, non-inferiority RCT performed in a large reproductive medicine centre in China. Infertile women with PCOS will be randomised to receive either IVM or standard IVF in a 1:1 treatment ratio after informed consent. IVF procedures used in our study are all standard treatments and other standard-assisted reproductive technologies will be similar between the two groups. The primary outcome is ongoing pregnancy leading to live birth within 6 months of the first oocyte retrieval cycle after randomisation. Pregnancy outcome, maternal safety and obstetric and perinatal complications will be secondary outcomes. The planned sample size is 350 (175 per group).Ethics and disseminationEthical permission was acquired from the Ethics Committee of Peking University Third Hospital. The results will be issued to publications through scientific journals and conference reports.Trial registration numberNCT03463772.
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Huang, Jin, Li Rong, Lin Zeng, Liang Hu, Juanzi Shi, Liyi Cai, Bing Yao, et al. "Embryo selection through non-invasive preimplantation genetic testing with cell-free DNA in spent culture media: a protocol for a multicentre, double-blind, randomised controlled trial." BMJ Open 12, no. 7 (July 2022): e057254. http://dx.doi.org/10.1136/bmjopen-2021-057254.
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IntroductionMorphological evaluation is used to select embryos for in vitro fertilisation. However, it does not fully reflect the implantation potential. Preimplantation genetic testing for aneuploidies (PGT-A) can detect embryonic aneuploidy, but biopsy procedure is invasive. Currently, a non-invasive PGT (ni-PGT) approach using spent medium is being evaluated. However, the clinical benefit of ni-PGT has not been clearly demonstrated. A multicentre randomised trial is needed to verify whether ni-PGT can be an new effective tool for evaluating embryos.Methods and analysisOverall, 1148 couples aged 35~42 (women) receiving in vitro fertilization–intracytoplasmic sperm injection are planned to be enrolled. Couples will be digitally randomised to (1) ni-PGT and (2) conventional morphology groups at a 1:1 treatment ratio. The primary outcome will be the ongoing pregnancy rate related to the first transfer cycle within 6 months after oocyte retrieval.Ethics and disseminationThe study protocol is approved by the Ethics Committee of Peking University Third Hospital and the participating hospitals. The results will be disseminated through international conferences and scientific journals.Trial registration numberNCT04339166.
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Dierke, Ariane, Bastian-Jesper Klußmann-Fricke, Paula Rosam, Christoph Brandt-Wunderlich, Luise Knorre, Michael Stiehm, Andrea Bock, et al. "Microstent for minimally invasive treatment of Fallopian tube occlusions – porcine implantation ex vivo." Current Directions in Biomedical Engineering 8, no. 2 (August 1, 2022): 628–31. http://dx.doi.org/10.1515/cdbme-2022-1160.
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Abstract Involuntary female infertility represents a sensitive issue, which is frequently caused by an impaired patency of the Fallopian tube. Current treatment options, such as in vitro fertilisation (IVF) or tubal reconstruction, are related to high costs or surgical risks. Therefore, a need for an alternative highly safe and effective minimally invasive therapy option is assumed. The current work presents a proof-of-concept for a novel microstent in combination with a delivery system for treatment of proximal Fallopian tube occlusions. For this purpose, a microstent prototype was implanted into a porcine Fallopian tube ex vivo using the presented delivery system. The results of the procedure were analyzed using a micro-computed tomography (μ-CT). Based on the μ-CT imaging, critical parameters of the microstent, such as radial patency, were assessed. The microstent implantation leads to an increased opening area of the Fallopian tube. Additionally, the microstent does not impair the anatomical shape of the tube epithelium and adapts well to the anatomical path. In further studies, the functionality of the Fallopian tube will be examined after microstent implantation in vivo.
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Mogas, Teresa. "Update on the vitrification of bovine oocytes and invitro-produced embryos." Reproduction, Fertility and Development 31, no. 1 (2019): 105. http://dx.doi.org/10.1071/rd18345.
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The combined use of reproductive technologies, such as transvaginal ovum-pick up and invitro embryo production followed by direct transfer of cryopreserved embryos, has great potential for enhancing genetic selection and optimising cross-breeding schemes in beef and dairy cattle production systems. This, along with an effective cryopreservation procedure for cow oocytes, will enable the long-term conservation of female genetic traits and the advance of embryo biotechnology in this species. However, the low fertilisation rates and developmental competence of cryopreserved oocytes still need to be improved. Over the past two decades, many research efforts tried to overcome individual features of the bovine oocyte that make it notoriously difficult to cryopreserve. In addition, pregnancy rates associated with invitro-produced (IVP) embryos remain lower than those obtained using invivo counterparts. This, together with a lack of a standard methodology for IVP embryo cryopreservation that provides easier and more practical logistics for the transfer of IVP embryos on farms, has hindered international genetic trade and the management of embryo banks. This review updates developments in oocyte and IVP embryo vitrification strategies targeting high production efficiency and better outcomes.
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Kanyó, Katalin, J. Konc, L. Solti, and S. Cseh. "Assisted reproductive research: Laser assisted hatching and spindle detection (spindle view technique)." Acta Veterinaria Hungarica 52, no. 1 (January 1, 2004): 113–23. http://dx.doi.org/10.1556/avet.52.2004.1.11.
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Animal experiments are very important for the development of new assisted reproductive techniques (ART) for use in human and animal reproductive medicine. Most technical aspects of reproductive manipulation of humans and animals are very similar, and many components of successful human ART used nowadays have been derived from animal studies. In this study we examined (1) the use of 'non-contact' laser for assisted hatching, (2) whether spindles in living mouse oocytes could safely be imaged/examined by polarisation microscope (polscope) and (3) the influence of environment (e.g. temperature, in vitro culture, etc.) on spindle detection/visualisation. The data of the study presented here show that (1) laser assisted hatching (AH) is a fast, very accurate and safe procedure without any harmful effect on embryo development and it can support very effectively the implantation of embryos, (2) the use of polscope facilitates the evaluation of oocyte quality and the selection of oocytes with spindle, (3) by monitoring the spindle position during intracytoplasmic sperm injection (ICSI), we can reduce spindle damage and increase the chance of fertilisation. Further studies are underway to test the hypothesised connection between spindle birefringence and developmental capacity of oocytes/embryos.
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Chastant-Maillard, Sylvie, Martine Chebrout, Sandra Thoumire, Marie Saint-Dizier, Marc Chodkiewicz, and Karine Reynaud. "Embryo biotechnology in the dog: a review." Reproduction, Fertility and Development 22, no. 7 (2010): 1049. http://dx.doi.org/10.1071/rd09270.
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Canine embryos are a scarce biological material because of difficulties in collecting in vivo-produced embryos and the inability, to date, to produce canine embryos in vitro. The procedure for the transfer of in vivo-produced embryos has not been developed adequately, with only six attempts reported in the literature that have resulted in the birth of 45 puppies. In vitro, the fertilisation rate is particularly low (∼10%) and the incidence of polyspermy particularly high. So far, no puppy has been obtained from an in vitro-produced embryo. In contrast, cloning of somatic cells has been used successfully over the past 4 years, with the birth of 41 puppies reported in the literature, a yield that is comparable to that for other mammalian species. Over the same period, canine embryonic stem sells and transgenic cloned dogs have been obtained. Thus, the latest reproductive technologies are further advanced than in vitro embryo production. The lack of fundamental studies on the specific features of reproductive physiology and developmental biology in the canine is regrettable in view of the increasing role of dogs in our society and of the current demand for new biological models in biomedical technology.
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Wilmut, Ian, Gareth Sullivan, and Jane Taylor. "A decade of progress since the birth of Dolly." Reproduction, Fertility and Development 21, no. 1 (2009): 95. http://dx.doi.org/10.1071/rd08216.
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The greatest effect of the birth Dolly, the first cloned animal derived from an adult, has been in prompting biologists to consider ways of reprogramming adult nuclei to a pluripotent state directly. The first procedure depends upon use of viral vectors to introduce selected transcription factors, but this procedure is slow and very inefficient. Research in our laboratory has demonstrated that exposure of differentiated nuclei to an extract of embryo stem cells induces expression of key pluripotency genes within 8 h, suggesting that it may be possible to identify and use other factors to enhance direct reprogramming. A study of mechanisms that bring about changes in DNA methylation in early sheep embryos identified a developmental isoform of Dnmt1, the expression of which was limited to early stages of pregnancy. Reduction in the level of transcript of this isoform at the time of fertilisation caused sheep embryo development to cease at the early morula stage, revealing a key role for the isoform that remains to be characterised. The ability to obtain pluripotent cells from specific patients is providing important new opportunities to study inherited diseases when the causative mutation is not known. The initial objective of this research is not cell therapy, but to use cells with the characteristics of those in a patient who has inherited the disease to establish a high-throughput screen to identify drugs that are able to prevent progression of the symptoms of the disease. Research is in progress with cells from patients with amyotropic lateral sclerosis.
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Estrada-Cortés, E., and P. J. Hansen. "54 Choline alters the pattern of DNA methylation and lipid content of pre-implantation bovine embryos." Reproduction, Fertility and Development 32, no. 2 (2020): 152. http://dx.doi.org/10.1071/rdv32n2ab54.
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Choline is a methyl donor for DNA methylation and a precursor for phosphatidylcholine, which is the major phospholipid of cell membranes. Early embryonic development involves processes of DNA demethylation and remethylation as well as synthesis of new cell membranes. Addition of choline chloride (ChCl) to culture medium of embryos produced invitro increased birthweight of Brahman calves after embryo transfer. The objective was to determine whether the addition of ChCl to culture medium alters the pattern of DNA methylation and lipid content of pre-implantation embryos produced invitro. Embryos were incubated after fertilisation in BBH7 culture medium containing 0.0, 0.004, 1.3, or 1.8mM ChCl (adjusted with NaCl to maintain isotonicity). Concentrations were chosen to approximate free choline (0.004mM) and total choline (1.30mM) in plasma of cows at week 1 postpartum and concentration of total choline in plasma of cows fed rumen-protected choline (1.8mM). Cleavage and blastocyst rate (n=8 replicates) were evaluated at Days 3 and 7.5 post-insemination, respectively. Embryos ≥8 cells (range 8 to 24 cells; stages near embryonic genome activation) and expanded blastocysts were harvested at Day 3.75 (n=232) and 7.5 (n=204) to estimate global DNA methylation by immunostaining for 5-methyl-cytosine. Methylation of DNA was estimated by calculating the ratio of fluorescence for 5-methyl-cytosine to that of propidium iodide (DNA). Another group of expanded blastocysts was harvested (n=99) to estimate lipid content using Nile Red. Embryo development was analysed by GLIMMIX procedure and fluorescence data by GLM procedure of SAS (SAS Institute Inc.). The proportion of zygotes that cleaved after fertilisation (77.5±2.3, 78.1±2.3, 74.5±2.4, and 80.1±2.2% for 0.0, 0.004, 1.3, and 1.8mM ChCl; P=0.2736) and cleaved embryos that became blastocysts (37.8±4.4, 41.5±4.6, 42.8±4.6, and 39.6±4.4%; P=0.5764) was similar between treatments. The DNA methylation at both days was affected by treatment (P<0.001). At Day 3.75, 1.3mM choline reduced methylation and there were no effects of other concentrations (1.13a±0.03, 1.04a±0.03, 0.92b±0.03, and 1.13a±0.04; means with different superscripts differ at P<0.05). For blastocysts, in contrast, DNA methylation was increased for embryos treated with 1.3 and 1.8mM choline (0.98a±0.04, 1.04ab±0.03, 1.25c±0.03, and 1.11b±0.03). Lipid content in blastocysts was also affected by treatment (P=0.0139). In particular, lipid content was higher for embryos treated with 1.3 and 1.8mM choline (409.1a±54.3, 542.3ab±62.3, 651.3b±54.3, and 583.9b±55.0). In conclusion, addition of ChCl to culture medium altered DNA methylation in bovine pre-implantation embryos produced invitro in a manner dependent on developmental stage and choline concentration. Likewise, ChCl increased lipid content in the resultant blastocysts. Support was provided by the Red Larson Endowment.
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Kasimir Klemedtsson, Å., and K. A. Smith. "The significance of nitrous oxide emission from biofuel crops on arable land: a Swedish perspective." Biogeosciences Discussions 8, no. 4 (July 8, 2011): 6743–74. http://dx.doi.org/10.5194/bgd-8-6743-2011.
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Abstract. The current regulations governing biofuel production in the European Union require that they have to mitigate climate change, by producing >35 % less greenhouse gases (GHG) than fossil fuels. There is a risk that this may not be achievable, since land use for crop production inevitably emits the strong GHG nitrous oxide (N2O), due to nitrogen fertilisation and cycling in the environment. We conclude that efficient agricultural crop production resulting in a good harvest and low N2O emission can fulfill the EU standard, and is possible under certain conditions for the Swedish agricultural and refinery production systems. However, in years having low crop yields total GHG emissions can be even higher than those released by burning of fossil fuels. In general, the N2O emission size in Sweden and northern Europe is such that there is a >50 % chance that the 35 % saving requirement will not be met. Thus ecosystem N2O emissions have to be convincingly assessed. Here we compare Swedish emission data with values estimated by means of statistical models and by a global, top-down, procedure; the measurements and the predictions often show higher values that would fail to meet the EU standard and thus prevent biofuel production development.
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Lavitrano, Marialuisa, Marco Busnelli, Maria Grazia Cerrito, Roberto Giovannoni, Stefano Manzini, and Alessia Vargiolu. "Sperm-mediated gene transfer." Reproduction, Fertility and Development 18, no. 2 (2006): 19. http://dx.doi.org/10.1071/rd05124.
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Since 1989, a new method for the production of transgenic animals has been available, namely sperm-mediated gene transfer (SMGT), based on the intrinsic ability of sperm cells to bind and internalise exogenous DNA molecules and to transfer them into the oocyte at fertilisation. We first described the SMGT procedure in a small animal model, with high efficiency reported in the mouse. In addition, we successfully adapted and optimised the technique for use in large animals; it was, in fact, highly efficient in the generation of human decay accelerating factor transgenic pig lines, as well as multigene transgenic pigs in which three different reporter genes, namely enhanced green fluorescent protein, enhanced blue fluorescent protein and red fluorescent protein, were introduced. The major benefits of the SMGT technique were found to be its high efficiency, low cost and ease of use compared with other methods. Furthermore, SMGT does not require embryo handling or expensive equipment. Sperm-mediated gene transfer could also be used to generate multigene transgenic pigs that would be of benefit as large animal models for medical research, for agricultural and pharmaceutical applications and, in particular, for xenotransplantation, which requires extensive genetic manipulation of donor pigs to make them suitable for grafting to humans.
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Ombelet, W., I. Van der Auwera, H. Bijnens, J. Onofre, C. Kremer, L. Bruckers, G. Mestdagh, R. Campo, and N. Dhont. "Improving IUI success by performing modified slow-release insemination and a patient-centred approach in an insemination programme with partner semen: a prospective cohort study." Facts, Views and Vision in ObGyn 13, no. 4 (December 2021): 359–67. http://dx.doi.org/10.52054/fvvo.13.4.045.
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Background: Pregnancy rates after in vitro fertilisation (IVF) treatment continue to improve, while intrauterine insemination (IUI) programmes show no such trend. There is a need to improve success rates with IUI to retain it as a viable option for couples who prefer avoiding IVF as a first line treatment. Objective: To investigate if a modified slow-release insemination (SRI) increases the clinical pregnancy rate (CPR) after intrauterine insemination (IUI) with partner semen. Materials and Methods: This was a prospective cohort study in a Belgian tertiary fertility centre. Between July 2011 and December 2018, we studied data from an ongoing prospective cohort study including 989 women undergoing 2565 IUI procedures for unexplained or mild/moderate male infertility. These data were analysed in order to study the importance of different covariates influencing IUI success. Generalised estimating equations (GEEs) were used for statistical analysis. Results of two periods (2011-2015, period 1 and 2016-2018, period 2) were examined and compared. From January 2016 (period 2) onwards, a standardised SRI procedure instead of bolus injection of sperm was applied. The primary outcome parameter was the difference in clinical pregnancy rate (CPR) per cycle between period 1 (bolus IUI) and period 2 (modified SRI). Secondary outcome results included all other parameters significantly influencing CPR after IUI. Results: Following the application of modified SRI the CPR increased significantly, from 9.03% (period 1) to 13.52% (period 2) (p = 0.0016). Other covariates significantly influencing CPR were partner’s age, smoking/non-smoking partner, BMI patient, ovarian stimulation protocol and Inseminating Motile Count (after semen processing). Conclusions: The intentional application of modified slow-release of processed semen appears to significantly increase CPRs after IUI with homologous semen. Future studies should investigate whether SRI, patient-centred measures, or a combination of both, are responsible for this improvement.
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Poppe, Kris, Peter Bisschop, Laura Fugazzola, Gesthimani Minziori, David Unuane, and Andrea Weghofer. "2021 European Thyroid Association Guideline on Thyroid Disorders prior to and during Assisted Reproduction." European Thyroid Journal 9, no. 6 (2020): 281–95. http://dx.doi.org/10.1159/000512790.
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Severe thyroid dysfunction may lead to menstrual disorders and subfertility. Fertility problems may persist even after restoring normal thyroid function, and then an assisted reproductive technology (ART) may be a solution. Prior to an ART treatment, ovarian stimulation is performed, leading to high oestradiol levels, which may lead to hypothyroidism in women with thyroid autoimmunity (TAI), necessitating levothyroxine (LT4) supplements before pregnancy. Moreover, women with the polycystic ovarian syndrome and idiopathic subfertility have a higher prevalence of TAI. Women with hypothyroidism treated with LT4 prior to ART should have a serum TSH level <2.5 mIU/L. Subfertile women with hyperthyroidism planning an ART procedure should be informed of the increased risk of maternal and foetal complications, and euthyroidism should be restored and maintained for several months prior to an ART treatment. Fertilisation rates and embryo quality may be impaired in women with TSH >4.0 mIU/L and improved with LT4 therapy. In meta-analyses that mainly included women with TSH levels >4.0 mIU/L, LT4 treatment increased live birth rates, but that was not the case in 2 recent interventional studies in euthyroid women with TAI. The importance of the increased use of intracytoplasmic sperm injection as a type of ART on pregnancy outcomes in women with TAI deserves more investigation. For all of the above reasons, women of subfertile couples should be screened routinely for the presence of thyroid disorders.
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Obrador, A., J. M. Alvarez, M. D. Fernández, and L. M. López-Valdivia. "Changes with time of zinc forms in an acid, a neutral, and a calcareous soil amended with three organic zinc complexes." Soil Research 40, no. 1 (2002): 137. http://dx.doi.org/10.1071/sr00099.
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Three zinc (Zn) fertilisers were added as soluble organic salts (Zn-ethylenediaminetetraacetate plus fulvic and humic acids, Zn-lignosulfonate plus ethylenediaminetetraacetate, and Zn-2-hydroxy-1,2,3-propanetricarboxilate) at several levels, to 3 representative types of soils, to study the behaviour of Zn applied. Samples of treated and untreated soils were incubated for 15, 30, and 60 days at 22˚C and field capacity. A selective sequential dissolution procedure and DTPA extraction were employed to determine the changes in Zn distribution. The distribution and the percentage conversion into different forms of the added metal were dependent on soil type, Zn sources, and Zn loading level. After an initial increase in all forms of Zn in the treated soils, Zn concentration in the water-soluble plus exchangeable fraction and the amounts extracted with DTPA began to decrease. At the end of the experiment, Zn in the most labile fraction was detected in the calcareous soil (pHw 8.3) only when the mixture of fulvic and humic acids with Zn-EDTA chelate was applied (e.g. 1.59 mg/kg of Zn in the 20 mg/kg treatment). The highest conversion values of Zn applied in this calcareous soil occurred in the amorphous Fe-oxide bound and residual fractions of all fertilisation treatments and a low conversion value occurred in the carbonate-bound fraction. fulvic acid, humic acid, Zn-EDTA, Zn-lignosulfonate, Zn-2-hydroxy-1,2,3-propanetricarboxilate, Zn extractability.
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Prasad, Bheem, Padamjeet Panchal, and Dayanidhi Kumar. "Dermatoglyphic study in Azoospermic and Oligozoospermic males." Biosciences Biotechnology Research Asia 17, no. 4 (January 15, 2021): 757–62. http://dx.doi.org/10.13005/bbra/2880.
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Introduction:Infertility resulting in men has evoked considerable medical and social interest. The dermatoglyphic study has been proven to be a useful diagnostic tool for different diseases. It is easy due to its cost-effectiveness and non-invasive procedure. Multiple aetiological factors are responsible for azoospermia and oligozoospermia. This study was done to know thedermatoglyphic patterns among male patients suffering from azoospermia and oligozoospermia and compare the findings with the general population. Methods:Total seventy-six cases suffering from azoospermia and oligozoospermia were taken with an equal number of individuals in the control group. The fingerprint patterns and ridge counts were compared with healthy age-matched control subjects. The fingerprint patterns were collected by standard ink method. The data was collected and subjected to Chi-square and analysis of variance at a 95 % confidence interval. Results:The overall frequency was loop was higher, followed by whorls and arches in men with azoospermia and oligozoospermia. It was observed that comparing the fingertip ridge patterns and their frequencies were significant (p<.05) inazoospermia and oligozoospermia as compared to controls.The increase in the total number of arches wasobserved in men with oligozoospermia as compared with respect to the control group. Thedifferencesin cases and control groups with respect to parameters such as Total finger ridge count (TFRC)as well as Absolute finger ridge count (AFRC) were found statistically insignificant. Conclusions:There is a substantial correlation between fingerprint patterns of men withazoospermia and oligozoospermiamales attending the In Vitro fertilisation Centre. These correlations may have an essential role in the early diagnosis of reproductive dysfunction in the future.
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Bongrani, Alice, Namya Mellouk, Christelle Ramé, Marion Cornuau, Fabrice Guerif, Pascal Froment, and Joëlle Dupont. "Vaspin, a novel adipokine in woman granulosa cells physiology and PCOS pathogenesis?" Journal of Endocrinology 249, no. 1 (April 2021): 57–70. http://dx.doi.org/10.1530/joe-20-0550.
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Vaspin is a novel adipokine mainly expressed in visceral adipose tissue and closely related to obesity and insulin-resistance. Currently, data about its ovarian expression are limited to animal models and its role in human reproduction is largely unexplored. Our study’s aims were then to characterise vaspin expression in the human ovary and to study in vitro its effects on granulosa cells physiology. Secondly, we assessed vaspin and its receptor GRP78 variations in granulosa cells and follicular fluid of a cohort of 112 infertile women undergoing an in vitro fertilisation procedure and allocated to three groups, each including normal-weight and obese subjects: 34 PCOS patients, 33 women with isolated polycystic ovary morphology (ECHO group) and 45 controls. Vaspin and GRP78 expression in the ovary was assessed by immunohistochemistry, RT-qPCR and Western blot. Granulosa cells and follicular fluid were analysed by RT-qPCR and ELISA, respectively. In vitro, granulosa cells metabolism was studied after stimulation with recombinant human vaspin, with and without a siRNA directed against GRP78. Vaspin was highly expressed in the human ovary and concentration-dependently enhanced granulosa cells steroidogenesis, proliferation and viability through GRP78 (P < 0.0001). Vaspin levels in both granulosa cells and follicular fluid were significantly higher in obese women (P < 0.0001) and in the normal-weight ECHO group (P < 0.001), which also had the highest expression rates of GRP78 (P < 0.05). Although further investigation is needed, vaspin appears as a novel modulator of human granulosa cells physiology and possibly plays a role in PCOS pathogenesis, notably protecting from insulin-resistance induced complications.
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Popović, Miroslav, and Tanja Milić-Radić. "Factors associated with frequency of ectopic pregnancy." Scripta Medica 53, no. 1 (2022): 47–50. http://dx.doi.org/10.5937/scriptamed53-35117.
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Background/Aim: Ectopic pregnancy is defined as a pregnancy outside the uterine cavity, most often in the fallopian tube. It is a life-threatening condition and requires early diagnosis and adequate care. Aim of this study was to examine the frequency of ectopic pregnancy, as well as the influence of parity, age of patients and previous in vitro fertilisation (IVF) procedure on the occurrence of ectopic pregnancy. Methods: A retrospective research was conducted in the Clinic for Gynaecology and Obstetrics of the University Clinical Centre of the Republic of Srpska from 1st of January 2016 up to 31 of December 2018, which included 125 hospitalised patients with a confirmed diagnosis of ectopic pregnancy. Data on the age of patients , parity and previous IVF, as well as the method of treatment of patients with ectopic pregnancy were analysed and compared. Results: In the observed period, there were a total of 9781 births and in the same period, 125 patients with a diagnosis of ectopic pregnancy were hospital-ised, which is 1.27 %. Pregnancy did not occur after IVF. Laparoscopy and drug therapy are represented almost equally, depending on the clinical picture and the wishes of the patients and open access was represented only sporadically. Conclusion: According to this research, the onset of ectopic pregnancy is not affected by age, parity and previous IVF, which does not fit into the results of world research. The most common form of treatment in our country is both lap-aroscopy and medical approach and open access occurs only sporadically, which fits into the recommendations of the relevant guides.
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Harris, J. P., J. L. Edwards, L. A. Rispoli, N. R. Rorhbach, T. M. Prado, A. M. Saxton, and F. N. Schrick. "13 MOTILITY CHARACTERISTICS OF SPERMATOZOA FROM BULLS GRAZING TALL FESCUE PASTURES." Reproduction, Fertility and Development 26, no. 1 (2014): 121. http://dx.doi.org/10.1071/rdv26n1ab13.
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Fertilisation is less than expected with spermatozoa from bulls consuming toxic endophyte-infected (E+) tall fescue. The objective of this study was to evaluate motility characteristics of spermatozoa from bulls grazing tall fescue pastures using computer-assisted sperm analysis (CASA). Semen was collected from six Angus bulls (average age = 15.1 ± 0.04 months) during a three-month grazing study. Bulls grazed Kentucky 31 tall fescue (Festuca arundinacea Schreb.) infected with Neotyphodium coenophialum, an ergot alkaloid-producing endophyte (n = 3), or Jesup tall fescue with Max-Q™ (NTE), a non-ergot alkaloid producing endophyte (n = 3), and grouped by body weight and scrotal circumference to graze pastures from April 18 to June 26. Semen was collected once per week between 0600–0800 h beginning in mid-May and ending the last week of June. Gross motility and morphology was evaluated before extending with Bioxcell® animal protein-free formula (IMV, Aigle, France) and antibiotics (CSS 100, 2% of total volume). Extended semen was then evaluated using CASA to determine final dilution and packaged into straws (20 million sperm/straw), where equilibration occurred over 3 h in a cold room at 4°C. Straws were frozen for 7 min in static vapor of liquid nitrogen and plunged into goblets filled with liquid nitrogen. Semen was thawed and assessed using CASA at 0 and 3 h post-thaw. Data were analysed as a randomised block design with the fixed effects of treatment, blocking on semen collection date, utilising the mixed models procedure of SAS 9.2 (SAS Institute Inc., Cary, NC, USA). Data were tested for normality (Shapiro-Wilk W ≥ 0.90), and treatment differences were determined using F-protected least significant differences. Path velocity (P = 0.001) and progressive velocity (P = 0.003) were lower in spermatozoa from bulls grazing E+ during the last 2 weeks of collection in June independent of time of assessment post-thaw. Sperm head area decreased in size in spermatozoa from E+ grazing bulls at 3 h post-thaw (P = 0.04) compared with NTE grazing bulls. Percent of rapid (progressive % with path velocity >50 μm s–1) and medium (progressive % with path velocity <50 μm s–1 but > 30μm s–1) velocity spermatozoa was decreased for E+ grazing bulls compared to NTE grazing bulls (P < 0.0001 and P = 0.004, respectively) and was accompanied by an increase in static (immobile) spermatozoa from E+ bulls (P < 0.0001). These findings indicate that spermatozoa movement and velocity are impaired in bulls grazing E+ tall fescue pastures compared to bulls grazing NTE tall fescue pastures after the freeze and thaw process, which may explain decreased fertilisation and cleavage rates of oocytes co-incubated with these spermatozoa.
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Messinis, Ioannis E. "Drugs Used in In Vitro Fertilisation Procedures." Drugs 38, no. 1 (July 1989): 148–59. http://dx.doi.org/10.2165/00003495-198938010-00006.
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Kamata, Yasuyuki, Kazuyuki Endo, Hiroyuki Nozaki, Akiko Fujiwara, and Ikuo Yasumasu. "Morphogenesis of exogut isolated from vegetalised embryo of sea urchin." Zygote 8, S1 (December 1999): S84. http://dx.doi.org/10.1017/s0967199400130497.
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It is well known that sea urchin embryos treated with lithium chloride (LiC1) develop to abnormally into vegetalised embryos, in which differentiation of ectodermal cells is inhibited. When embryos of the sea urchins, Hemicentrotus pulcherrimus and Anthocidaris crassispina were treated with 20 mM LiC1 from the 8-cell stage to the corresponding early gastrula stage, they developed to vegetalised embryos with a large exogut 45 h after fertilisation. In these vegetalised embryos, high activity of alkaline phosphatase (AP) was detected histochemically at the end of the exogut where it is attached to the embryo body. High activity of AP is known to be detected specifically in the gut of sea urchin pluteus larvae by the same procedure as used in this study. Hence, we concluded that this part of the exogut is composed of the cells which develop into the cells of the gut in normal development.When exogut isolated from vegetalised embryos was cultured in the extract obtained from eggs or embryos, the end composed of the cells in which high AP activity was detected, expanded during culture and formed a large spherical structure about 24 h after the initiation of culture. The minimum concentration of extract to cause expansion of isolated exogut was 5 × 103 egg or embryo equivalent/ml ASW (artificial seawater). The extract boiled at 95 °C for 1 h also caused expansion of isolated exogut at the same concentrations as non-boiled extract. On the other hand, the extract obtained from eggs or embryos by chloroform–methanol extraction did not cause any expansion of exogut, but the aqueous phase, heat-dried and dissolved in ASW, induced expansion of isolated exogut.
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Flechard, C. R., C. Spirig, A. Neftel, and C. Ammann. "The annual ammonia budget of fertilised cut grassland – Part 2: Seasonal variations and compensation point modeling." Biogeosciences Discussions 6, no. 5 (October 7, 2009): 9627–75. http://dx.doi.org/10.5194/bgd-6-9627-2009.
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Abstract. The net annual NH3 exchange budget of a fertilised, cut grassland in Central Switzerland is presented. The observation-based budget was computed from semi-continuous micrometeorological fluxes over a time period of 16 months and using a process-based gap-filling procedure. The data for emission peak events following the application of cattle slurry and for background exchange were analysed separately to distinguish short-term perturbations from longer-term ecosystem functioning. A canopy compensation point model of background exchange is parameterised on the basis of measured data and applied for the purposes of gap-filling. The data show that, outside fertilisation events, grassland behaves as a net sink for atmospheric NH3 with an annual dry deposition flux of −3.0 kg N ha−1 yr−1, although small NH3 emissions by the canopy were measured in dry daytime conditions. The median Γs ratio in the apoplast (=[NH4+]/[H+]) estimated from micrometeorological measurements was 620, equivalent to a stomatal compensation point of 1.3 μg NH3 m−3 at 15°C. Non-stomatal resistance to deposition Rw was shown to increase with temperature and decrease with surface relative humidity, and Rw values were among the highest published for European grasslands, consistent with a relatively high ratio of NH3 to acid gases in the boundary layer at this site. Since the gross annual NH3 emission by slurry spreading was of the order of +20 kg N ha−1 yr−1, the fertilised grassland was a net NH3 source of +17 kg N ha−1 yr−1. A comparison with the few other measurement-based budget values from the literature reveals considerable variability, demonstrating both the influence of soil, climate, management and grassland type on the NH3 budget and the difficulty of scaling up to the national level.
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Flechard, C. R., C. Spirig, A. Neftel, and C. Ammann. "The annual ammonia budget of fertilised cut grassland – Part 2: Seasonal variations and compensation point modeling." Biogeosciences 7, no. 2 (February 8, 2010): 537–56. http://dx.doi.org/10.5194/bg-7-537-2010.
Full textAbstract:
Abstract. The net annual NH3 exchange budget of a fertilised, cut grassland in Central Switzerland is presented. The observation-based budget was computed from semi-continuous micrometeorological fluxes over a time period of 16 months and using a process-based gap-filling procedure. The data for emission peak events following the application of cattle slurry and for background exchange were analysed separately to distinguish short-term perturbations from longer-term ecosystem functioning. A canopy compensation point model of background exchange is parameterised on the basis of measured data and applied for the purposes of gap-filling. The data show that, outside fertilisation events, grassland behaves as a net sink for atmospheric NH3 with an annual dry deposition flux of −3.0 kg N ha−1 yr−1, although small NH3 emissions by the canopy were measured in dry daytime conditions. The median Γs ratio in the apoplast (=[NH4+]/[H+]) estimated from micrometeorological measurements was 620, equivalent to a stomatal compensation point of 1.3 μg NH3 m−3 at 15 °C. Non-stomatal resistance to deposition Rw was shown to increase with temperature and decrease with surface relative humidity, and Rw values were among the highest published for European grasslands, consistent with a relatively high ratio of NH3 to acid gases in the boundary layer at this site. Since the gross annual NH3 emission by slurry spreading was of the order of +20 kg N ha−1 yr−1, the fertilised grassland was a net NH3 source of +17 kg N ha−1 yr−1. A comparison with the few other measurement-based budget values from the literature reveals considerable variability, demonstrating both the influence of soil, climate, management and grassland type on the NH3 budget and the difficulty of scaling up to the national level.