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Recoleta uterina como estratégia para aumentar a taxa de embriões em fêmeas bovinas de corte e leite; Uterine re-flushing as a strategy to improve embryo recovery rate in dairy and beef cattle

CRUZ, Fabiano Buss; ORTIGARI JUNIOR, Ivens; VIEIRA, Arnaldo Diniz; GERGER, Renato Pereira da Costa; RIBEIRO, Eduardo de Souza; BERTOLINI, Marcelo; MEZZALIRA, Alceu
Fonte: UNIV FED RIO GRANDE DO SUL Publicador: UNIV FED RIO GRANDE DO SUL
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
36.68%
Embryo recovery rate in superovulated cows after uterine flushing is lower than the ovulation rate, which contributes to the relative inefficiency of the conventional cervical recovery procedure. A simple and easy alternative to improve embryo recovery rate is the uterine re-flushing procedure. To evaluate the effect of re-flushing and the influence of breed and operator on bovine embryo recovery rate, 38 Nelore and 19 Jersey females were stimulated using FSH, with embryos being collected by one of two trained operators. At the end of flushing, the catheter was sealed and maintained into the uterine body, filled with flushing medium, while females were released to a paddock for 30 to 50 min, to be submitted to the re-flushing procedure by the same operator. A total of 599 structures were recovered out of 57 procedures, from which 423 (70.6%) were obtained in the first flushing and 176 (29.4%) after re-flushing. Mean recovery rates of 7.4 and 3.1 structures were obtained after the first and second flushing, respectively, for a total of 10.5 structures per cow. Structures were obtained in 73.6% ( 42 out of 57) of the re-flushing procedures. No breed effect was observed on total ova or embryo recovery, with 10.9 total ova collected from Jersey and 10.3 from Nelore females. Likewise...

Fatores associados à produção e à sobrevivência embrionária em programas de superovulação e transferência de embriões em fêmeas da raça Holandesa em clima tropical; Factors associated to embryo production and survival in superovulation programs and embryo transfer in Holstein females raised in tropical climate

Vieira, Lais Mendes
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 06/02/2013 PT
Relevância na Pesquisa
36.75%
A alta variabilidade na resposta aos tratamentos superovulatórios e na produção de embriões tem sido relacionada a causas multifatoriais. Além disso, são restritas as informações que relacionam fatores correlatos ao embrião à concepção. Dessa forma, o objetivo do presente estudo foi avaliar a influência de variáveis relacionadas às doadoras (categoria animal e época do ano de produção do embrião) na eficiência de programas de superovulação (SOV), assim como na eficiência reprodutiva de receptoras em programas de transferência de embrião. Foram avaliados dados de 1.562 protocolos de SOV (609 em vacas em lactação e 953 em novilhas da raça Holandesa) e 4.076 transferências de embrião (receptoras Holandesas em lactação). A taxa de SOV (número de doadoras com dois ou mais CL) foi semelhante entre novilhas e vacas em lactação (89,7 vs. 91,9%, respectivamente; P = 0,26). A época do ano, também, não influenciou a taxa de SOV (época quente = 89,3% vs. época não quente = 92,2%; P = 0,09). Doadoras lactantes apresentaram maior número de CL (10,6 ± 0,6 vs. 7,5 ± 0,4; P < 0,0001), de estruturas recuperadas (7,6 ± 0,6 vs. 4,6 ± 0,4; P < 0,0001) e taxa de recuperação (77,6 vs. 58,7%; P < 0,0001) que novilhas. Doadoras superovuladas na época quente apresentaram menor número de CL (8...

Produção de embriões e fisiologia ovariana em vacas nelore sob diferentes níveis nutricionais; Embryo production and ovarian physiology in cows under different levels nutritional nellore

Surjus, Ricardo da Silva
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 28/02/2013 PT
Relevância na Pesquisa
36.68%
A nutrição está intimamente relacionada com a reprodução nos animais e ainda há muito a se estudar sobre essa inter-relação, principalmente porque ainda há muita controvérsia na literatura sobre este tema. Por exemplo, alguns estudos sugerem ser benéfico o uso do "flushing" nutricional na produção de embriões em ruminantes. Entretanto, a maioria dos trabalhos mostra resultados negativos da alta ingestão de matéria seca (IMS). Dessa forma, existe a necessidade em se avançar nos estudos comparando a fisiologia reprodutiva e produção de embriões em fêmeas sob diferentes níveis nutricionais. Foram utilizadas 33 vacas Nelores não lactantes recebendo um dos quatro tratamentos a seguir: Os grupos Mantença (M), Restrição (0,7M) e Alta IMS (1,5M) receberam a mesma dieta padrão variando a quantidade oferecida. O grupo Alta ingestão de energia (E), recebeu uma dieta com alto teor de amido, com a mesma energia do grupo 1,5M, porém, com a mesma IMS do grupo M. Todas as vacas passaram por todos os tratamentos, em um modelo crossover. Estes animais tiveram o ciclo estral sincronizado e acompanhamento ovariano diário, por meio de ultrassonografia até confirmação da ovulação. Posteriormente, nos dias 7 e 10 do ciclo estral foi avaliado o volume do corpo lúteo (CL). Concentrações circulantes de hormônios esteróides (progesterona [P4] e estradiol [E2]) foram mensuradas em dias estratégicos. Os animais foram submetidos à aspiração intrafolicular (OPU) por volta do dia 12 do ciclo estral e dois dias após a OPU...

Effects of timing of induced luteolysis in embryo donor mares on reproductive performance and pregnancy rate in recipient mares

Goretti, R. G.; Araujo, R. R.; Rocha Filho, A. N.; Araujo, G. H. M.; Lopes, E. P.; Guimaraes, J. D.
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 1170-1174
ENG
Relevância na Pesquisa
36.75%
The objective was to evaluate the effects of giving prostaglandin F(2 alpha) (PGF) to donor mares 48 h prior to embryo collection. Non-lactating donor mares (n = 20 estrous cycles in 10 mares), ranging from 2.5 to 10 y of age and 400 to 500 kg of body weight were used from September 2004 to February 2005 in the southern hemisphere (Brazil). Donor mares were randomly assigned in a cross-over design study. During a Treated cycle, 7.5 mg PGF was given 48 h prior to embryo collection, whereas in the Control cycle, 7.5 mg PGF was given at embryo collection. In Treated Cycles, serum progesterone concentrations decreased between the day of PGF treatment and the day of embryo collection (13.9 +/- 5.4 and 0.5 +/- 0.3 ng/mL, respectively; P < 0.05). In Treated versus Control cycles, the interovulatory interval was shorter (14.9 +/- 0.9 vs 17.5 +/- 1.1 d, P < 0.05). However, there was no significant difference between these groups for the interval from PGF to ovulation (average, 9.8 d), embryo recovery rate (average, 75%), embryo quality, uterine protein concentration, and pregnancy rate in recipient mares (average, 87% at 15 d after ovulation, with no pregnancy loss detected by 60 d). In conclusion, giving donor mares PGF 48 h prior to embryo collection reduced the average interovulatory interval by approximately 2.5 d...

The effect of type of vaginal insert and dose of pLH on embryo production, following fixed-time AI in a progestin-based superstimulatory protocol in Nelore cattle

Nogueira, Marcelo F. Gouveia; Fragnito, Paulo S.; Trinca, Luzia A.; Barros, Ciro M.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 655-660
ENG
Relevância na Pesquisa
36.7%
The objective was to analyze and report field data focusing on the effect of type of progesterone-releasing vaginal insert and dose of pLH on embryo production, following a superstimulatory protocol involving fixed-time artificial insemination (FTAI) in Nelore cattle (Bos taurus indicus). Donor heifers and cows (n = 68; 136 superstimulations over 2 years) received an intravaginal, progesterone-releasing insert (CIDR® or DIB®, with 1.9 or 1.0 g progesterone, respectively) and 3-4 mg of estradiol benzoate (EB) i.m. at random stages of the estrous cycle. Five days later (designated Day 0), cattle were superstimulated with a total of 120-200 mg of pFSH (Folltropin-V®), given twice daily in decreasing doses from Days 0 to 3. All cattle received two luteolytic doses of PGF2α at 08:00 and 20:00 h on Day 2 and progesterone inserts were removed at 20:00 h on Day 3 (36 h after the first PGF2α injection). Ovulation was induced with pLH (Lutropin-V®, 12.5 or 25 mg, i.m.) at 08:00 h on Day 4 with FTAI 12, 24 and in several cases, 36 h later. Embryos were recovered on Days 11 or 12, graded and transferred to synchronous recipients. Overall, the mean (±S.E.M.) number of total ova/embryos (13.3 ± 0.8) and viable embryos (9.4 ± 0.6) and pregnancy rate (43.5%; 528/1213) did not differ among groups...

Use of long-acting progesterone to acyclic embryo recipient mares

Greco,Gabriel Maksoud; Burlamaqui,Fábio Luis Gonçalves; Pinna,Aline Emerim; Queiroz,Fernando José Rohen de; Cunha,Maria Pia dos Santos; Brandão,Felipe Zandonadi
Fonte: Sociedade Brasileira de Zootecnia Publicador: Sociedade Brasileira de Zootecnia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2012 EN
Relevância na Pesquisa
36.75%
The objective of this study was to evaluate the efficiency of cyclic and acyclic progesterone-treated recipient mares in a commercial embryo transfer program. Acyclic recipients were treated with decreasing amounts of estradiol cypionate (ECP® - Pfizer Saúde Animal, São Paulo, Brazil), followed by 1500 mg of a sustained-release progesterone injection (P4LA150® - Laboratórios B.E.T., Rio de Janeiro, Brazil). Out of all 1506 embryo recovery attempts performed, 59.36% were positive (894/1506). Pregnancy rates of cyclic and acyclic mares were, respectively, 44.12% (319/723) and 57.68% (139/241) - higher in acyclic recipients under progesterone treatment. Embryo loss was similar between groups (9.72% 31/319 vs. 11.51% - 16/139). When fertility data on acyclic mares treated with long-action progesterone were grouped in relation to the interval of the beginning of the treatment with progesterone to the embryo transfer, there was no difference in pregnancy rates at 12 days (51.28% - 20/39; 58.92% - 33/56; 60.52% - 46/76 and 58.57% - 41/70 for embryos transferred 3 (P3), 4 (P4), 5 (P5) and 6 (P6) days after the beginning of the treatment with progesterone). Groups P3, P4, P5 and P6 showed embryo loss rates of 20.00% (4/20), 12.12% (4/33)...

Frozen-thawed embryo transfer: influence of clinical factors on implantation rate and risk of multiple conception

Wang, X.; Yap, Y.; Matthews, C.
Fonte: Oxford Univ Press Publicador: Oxford Univ Press
Tipo: Artigo de Revista Científica
Publicado em //2001 EN
Relevância na Pesquisa
36.77%
BACKGROUND: Frozen embryo transfer is an important supplementary procedure in the treatment of infertility. While general information concerning the outcome of frozen embryo transfer has been documented, few studies have addressed the potential of embryo implantation in particular clinical situations. Importantly, the risk of multiple conception following frozen embryo transfer has been poorly documented compared with the information available for fresh embryo transfer. METHODS: This is a retrospective study analysing 3570 frozen embryo transfer cycles (1438 couples) with a view to increasing our understanding of the clinical circumstances that influence the potential for embryo implantation. RESULTS: The overall implantation rate was 9.1%. The characteristics associated with a more favourable implantation rate were the success of the previous fresh embryo transfer cycle, age < 40 years and non-tubal factor aetiology of infertility. Such women had an increased risk of multiple conception. CONCLUSION: Female age, the aetiology of infertility and the outcome of fresh embryo transfer are the most important factors influencing the implantation rate following frozen embryo transfer. A prognostic table has been constructed that may assist with the determination of the optimal number of embryos to be replaced in frozen embryo transfer to provide better individualized counselling and to secure an optimal chance of pregnancy while reducing the risk of multiple conception.; Wang...

Granulocyte-macrophage colony-stimulating factor alleviates adverse consequences of embryo culture on fetal growth trajectory and placental morphogenesis

Sjoblom, C.; Roberts, C.; Wikland, M.; Robertson, S.
Fonte: Endocrine Soc Publicador: Endocrine Soc
Tipo: Artigo de Revista Científica
Publicado em //2005 EN
Relevância na Pesquisa
36.72%
Growth factors secreted by the female reproductive tract promote development of the preimplantation embryo and potentially act as epigenetic determinants of postimplantation developmental competence and pregnancy outcome. In a comprehensive embryo transfer study in mice, we examined the late gestational and postnatal effects of embryo exposure to the cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF), identified as a key physiological regulator of cell number and viability in mouse and human blastocysts. Embryo development in culture in the absence of GM-CSF restricted fetal growth, accelerated postnatal growth, and increased adult body mass and adiposity in offspring compared with in vivo-grown embryos, especially in males. Addition of GM-CSF to embryo culture medium increased the proportion of transferred embryos that generated viable progeny and alleviated the effects of in vitro culture on fetal and postnatal growth trajectory but did not prevent programming of adult obesity. Placental morphogenesis was modified by embryo culture, which inhibited development of labyrinthine exchange tissue and adversely altered some structural correlates of placental transfer function. GM-CSF reversed the effect of culture on labyrinthine growth and increased the surface area of placental trophoblast available for nutrient exchange. These findings indicate that the detrimental influence of embryo culture on fetal viability and growth may be largely mediated through altered placental morphogenesis and can be alleviated by GM-CSF. This demonstrates that embryonic exposure to GM-CSF is essential for normal placental development and fetal growth.; Cecilia Sjöblom...

Day 4 embryo selection is equal to Day 5 using a new embryo scoring system validated in single embryo transfers

Inglis, D.; Henshaw, R.; Lane, M.
Fonte: Oxford Univ Press Publicador: Oxford Univ Press
Tipo: Artigo de Revista Científica
Publicado em //2008 EN
Relevância na Pesquisa
36.7%
BACKGROUND: Single embryo transfers (SETs) require the most viable embryo from a cohort to be selected. Day 4 embryos may provide a selection advantage similar to blastocyst transfer as embryos are replaced post-embryonic genome activation and into the uterus where they would normally reside. However, there is currently no adequate morphological system to assess Day 4 embryos. Therefore, we developed an assessment system for Day 4 embryos and retrospectively assessed Day 4 SET success rates compared with Day 5 SETs. METHODS: Embryos (n = 996 after IVF or ICSI) were assessed on Day 4 of development, prior to implementing Day 4 embryo transfers, to obtain a descriptive range of embryo morphologies observed at this time point. A morphological scoring system was developed from this. All patients having an SET after extended culture (Day 4, n = 124 or Day 5, n = 193), at Repromed, Adelaide, Australia, during June 2006-January 2007 were analysed for pregnancy outcome. Ongoing pregnancy was determined by fetal cardiac activity at 6-8 weeks after oocyte collection. RESULTS: Day 4 and 5 SETs resulted in similar ongoing pregnancy rates of 38.7% and 32.1%, respectively. CONCLUSIONS: A Day 4 scoring system was successfully developed and implemented. Day 4 SETs were found to be a viable option or alternative to Day 5 SETs with no difference in pregnancy rates.; Deanne Feil...

The impact of in vitro stress on pre-implantation embryo development, viability and mitochondrial homestasis.

Zander, Deirdre Linda
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2010
Relevância na Pesquisa
36.79%
It is recognised that the environment to which the fetus is exposed in utero, after implantation, can program longer term health outcomes and alter the possibility of disease onset later in life. It is becoming evident that the environment, to which the pre-implantation embryo is exposed, can also affect the ability of the embryo to form a viable pregnancy as well as altering fetal growth. Despite this understanding, little is known about the mechanism by which the environment can ‘program’ the pre-implantation embryo. Using model stress systems, either ammonium or DMO in the culture medium, this thesis addressed the hypothesis that suboptimal environmental conditions may alter mitochondrial homeostasis and function and/or epigenetic parameters and these are the possible mechanisms responsible for the altered fetal outcomes seen. While common measures of embryo quality such as on time blastocyst development were not affected by either stress, more in-depth investigations found several striking differences. Exposure to DMO significantly decreased blastocyst cell number and allocation to the inner cell mass and trophectoderm, as well as increased blastocyst apoptosis. After exposure to DMO, blastocysts were transferred to pseudopregnant recipients...

Alterations in mouse embryo intracellular pH by DMO during culture impair implantation and fetal growth

Zander, D.; Mitchell, M.; Thompson, J.; Lane, M.
Fonte: Reproductive Healthcare Ltd. Publicador: Reproductive Healthcare Ltd.
Tipo: Artigo de Revista Científica
Publicado em //2010 EN
Relevância na Pesquisa
36.72%
The preimplantation embryo is highly susceptible to in-vitro stress, and although this does not necessarily perturb blastocyst development, it can significantly affect embryo physiology and the ability to form a viable pregnancy. This study determined that the preimplantation mouse embryo is highly sensitive to a small decrease in intracellular pH (<0.2 pH units). Embryos cultured in media containing a weak acid (5,5-dimethyl-2,4-oxazolidinedione; DMO) formed blastocysts with decreased cell number and inner cell mass number, as well as increased apoptosis, even though blastocyst development and morphology were unchanged. Interestingly, the effects were similar regardless of whether the pH stress was present for a short-term ‘acute’ exposure (during the zygote to 2-cell, or 2-cell to 8-cell division) or an extended ‘chronic’ period of time (continually from the zygote to the blastocyst stage). Exposure to DMO during the first cleavage division did not alter implantation; however, fetal weight and crown–rump length were significantly decreased (P < 0.05). In contrast, continuous exposure to DMO throughout preimplantation development reduced not only implantation but also fetal weight and crown–rump length. This study highlights the importance of correct intracellular pH and demonstrates that slight deviations can significantly impact embryo development and viability. The early embryo is known to be sensitive to its environment. This study determined the effect of a small alteration to pH of the culture environment on the ability of the embryo to grow and develop into a successful pregnancy. We found that the younger the embryo was the less capable it was to cope with the stress. Also embryos that appeared normal by observation were often not and by closer examination were showing signs of stress within the cells of the embryo resulting in poor pregnancy outcomes.; Deirdre L. Zander-Fox...

Clinical effectiveness of elective single versus double embryo transfer: meta-analysis of individual patient data from randomised trials

McLemon, D.; Harrild, K.; Bergh, C.; Davies, M.; de Neubourg, D.; Demoulin, J.; Gerris, J.; Kremer, J.; Martikainen, H.; Mol, B.; Norman, R.; Thurin-Kjellberg, A.; Tiitinen, A.; van Montfoort, A.; van Peperstraten, A.; van Royen, E.; Bhattacharya, S.
Fonte: British Med Journal Publ Group Publicador: British Med Journal Publ Group
Tipo: Artigo de Revista Científica
Publicado em //2010 EN
Relevância na Pesquisa
36.83%
Objective: To compare the effectiveness of elective single embryo transfer versus double embryo transfer on the outcomes of live birth, multiple live birth, miscarriage, preterm birth, term singleton birth, and low birth weight after fresh embryo transfer, and on the outcomes of cumulative live birth and multiple live birth after fresh and frozen embryo transfers. Design: One stage meta-analysis of individual patient data. Data sources: A systematic review of English and non-English articles from Medline, Embase, and the Cochrane Central Register of Controlled Trials (up to 2008). Additional studies were identified by contact with clinical experts and searches of bibliographies of all relevant primary articles. Search terms included embryo transfer, randomised controlled trial, controlled clinical trial, single embryo transfer, and double embryo transfer. Review methods: Comparisons of the clinical effectiveness of cleavage stage (day 2 or 3) elective single versus double embryo transfer after fresh or frozen in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI) treatments were included. Trials were included if the intervention differed only in terms of the intended number of embryos to be transferred. Trials that involved only blastocyst (day five) transfers were excluded. Results: Individual patient data were received for every patient recruited to all eight eligible trials (n=1367). A total of 683 and 684 women randomised to the single and double embryo transfer arms...

Single blastocyst embryo transfer maintains comparable pregnancy rates to double cleavage-stage embryo transfer but results in healthier pregnancy outcomes

Zander-Fox, D.; Tremellen, K.; Lane, M.
Fonte: Blackwell Publishing Asia Publicador: Blackwell Publishing Asia
Tipo: Artigo de Revista Científica
Publicado em //2011 EN
Relevância na Pesquisa
36.7%
Background: The optimal outcome after IVF is a live, healthy, singleton term baby. This can be achieved by transferring a single embryo, but at the possible expense of reducing pregnancy rates. Recent studies suggest that delaying transfer of embryos to the blastocyst stage (day 4 ⁄ 5), rather than the more traditional cleavage stage (day 2–3), allows for better selection of the best embryo, maximising pregnancy rates from a single embryo transfer (SET). The aim of this study was to assess pregnancy outcomes in relation to changing embryo transfer practices. Methods: A retrospective analysis of pregnancy outcomes was made between IVF cycles conducted in 2007 when blastocyst SET became standard practice, with IVF cycles in 2003 when double cleavage-stage embryo transfer was the norm. Results: The implementation of a blastocyst SET policy resulted in a significant decrease in multiple birth rates, while maintaining live birth delivery rate comparable to double cleavage-stage transfer (27.2% versus 24.8%, respectively, N.S.). Conclusion: Improvements in culturing protocols have facilitated extended culture, increasing embryo selection capability. These results indicate that it is now possible to maintain excellent pregnancy rates with SET blastocyst culture...

Perceptions of embryo status and embryo use in an Australian community

De Lacey, S.; Rogers, W.; Braunack-Mayer, A.; Avery, J.; Smith, D.; Richards, B.
Fonte: Reproductive Healthcare Ltd. Publicador: Reproductive Healthcare Ltd.
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
36.72%
Increasingly, important areas of medical therapy and research rely on the donation and use of human embryos. Yet their use is commonly determined by community tolerance and ethico-legal regulation. The aim of this study was to explore the views of an Australian community about what an embryo is, how it should be used and who should make disposition decisions. The findings of a large representative population survey showed that most participants thought of an embryo as human or potentially human but that this did not affect a majority community view that embryos should be used rather than discarded. This study also found divergent views about what the community perceived to be acceptable uses of embryos. The majority perceived the couple as having the authority to make a disposition decision. Women held different views to men across all three questions. The way an embryo was perceived related significantly to how it should be used and who should decide its disposition. These differences and relationships should be considered when developing clinic practices and ethico-legal frameworks to regulate embryo use in science or treatment.; Sheryl de Lacey, Wendy Rogers, Annette Braunack-Mayer, Jodie Avery, David Smith, Bernadette Richards

Stimulation of mitochondrial embryo metabolism via dichloroacetate acid in an aged mouse model improves embryo development and viability

McPherson, N.; Zander-Fox, D.; Lane, M.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2014 EN
Relevância na Pesquisa
36.72%
OBJECTIVE To determine whether supplementation of embryo culture media with a substrate to stimulate mitochondrial activity improves embryo viability and pregnancy establishment in aged mice. DESIGN Female mice were superovulated and mated. Zygotes were collected and cultured in either G1/G2 or G1/G2 with 1.0 mM dichloroacetic acid (DCA), a stimulator of pyruvate dehydrogenase complex. Embryos were cultured to the blastocyst stage and transferred into pseudopregnant female mice. SETTING University research facility. ANIMAL(S) Swiss female mice 26- to 28-week-old. INTERVENTION(S) The addition of DCA to the embryo culture media. MAIN OUTCOME MEASURE(S) Embryo development, total, trophectoderm, inner cell mass (ICM) and epiblast cell number, mitochondrial membrane potential, reactive oxygen species, pyruvate oxidation, adenosine triphosphate (ATP) output, implantation rates, and fetal and placental size and weights. RESULT(S) Supplementation of the embryo culture medium with DCA significantly increased blastocyst development rates in vitro, significantly improved total, trophectoderm, and ICM cell numbers and pluripotency of the ICM, significantly increased pyruvate oxidation and ATP output, and significantly increased fetal weights and size comparable to in vivo conditions. CONCLUSION(S) This study demonstrates that the addition of DCA to embryo culture media improves mitochondrial output in embryos produced from aged mice. Although DCA itself may be of limited therapeutic value in a clinical setting due to its low threshold of dosage and high toxicity...

Cytokines and programming the pre-implantation embryo.

Chin, Peck Yin
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2014
Relevância na Pesquisa
36.8%
As the pre-implantation embryo traverses the female reproductive tract, it experiences fluctuations in the composition of the surrounding maternal environment, including the availability of nutrients, growth factors and cytokines. In particular, the cytokine milieu surrounding the early embryo is pivotal in programming optimal embryo development. The pre-implantation embryo is sensitive to a range of perturbations such as maternal diet or in vitro culture. These and other insults influencing the maternal environment including infection, stress and environmental toxins may in part act via impact on oviduct and uterine cytokine synthesis. However the effect of maternal perturbation to inflammation or infection, on the embryo and the role of cytokines in mediating this is not fully elucidated. The studies described in this thesis employed an in vivo mouse model of maternal systemic inflammation with the proinflammatory bacterial lipopolysaccharide (LPS), where a pro-inflammatory cytokine response was elicited on days 2.5 and 3.5 post coitum (pc), prior to implantation. This model was studied in wildtype C57Bl/6 (Il10 ⁺ʹ⁺) mice and mice with a null mutation in the Il10 gene (Il10 ⁻ʹ⁻) were studied to investigate the effects of maternal deficiency in the anti-inflammatory cytokine IL-10 during LPS treatment. We demonstrated that the altered cytokine signals resulting from a low level pro inflammatory LPS challenge (0.5 μg/mouse) in the pre-implantation period elicit changes in the embryo developmental trajectory that in turn alter fetal growth and delay postnatal growth in the male progeny from LPS-treated mothers. As LPS did not directly impact development of the embryo at low and moderate doses...

Der Hühnerembryo als Modell für intrauterine, ultraschallgesteuerte Herzinterventionen; The chick embryo as model for intrauterine ultrasound-guided heart intervention

Fechner, Sandra
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
DE_DE
Relevância na Pesquisa
36.7%
Für Kinder mit einer pränatal diagnostizierten Aorten- oder Pulmonalklappenstenose oder einem hypoplastischen Linksherzsyndrom kommt die derzeit durchgeführte postnatale Behandlung häufig zu spät. Die Krankheitsbilder verlaufen progredient. Durch die veränderte intrakardiale und intravaskuläre Hämodynamik treten irreversible Sekundärschädigungen auf. Die Langzeitüberlebenschancen sind trotz postpartaler chirurgischer Maßnahmen gering, Spontanheilungen wurden bisher nicht beschrieben. Daher gewinnt die frühzeitige pränatale Behandlung immer mehr an Bedeutung. Derzeit gibt es auf dem Gebiet der pränatalen, minimalinvasiven, ultraschallgesteuerten Herzpunktion zur kathetergesteuerten Ballondilatation, abgesehen von experimentellen Einzelfallberichten, noch keine etablierten Behandlungsmöglichkeiten. Auch bisher durchgeführte Tierversuche stehen weit hinter dem theoretisch Möglichen zurück. Da minimalinvasive Behandlungen in der Zukunft der Pränatalmedizin eine wichtige Rolle spielen, wurde in der vorliegenden Arbeit der Hühnerembryo als Tiermodell für ultraschallgesteuerte, intrauterine Herzpunktionen untersucht. Beim menschlichen Feten ist eine Intervention zwischen der 18. und 33. Schwangerschaftswoche möglich...

Seminal plasma cytokines as determinants of ovulation, embryo development and pregnancy success in the pig.

O'Leary, Sean
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2010
Relevância na Pesquisa
36.7%
Determinants of litter size in the pig are ovulation rate, fertilisation rate and embryo and fetal mortality. In practice, litter size is normally about half the ovulation rate with 40% or more of potential piglets being lost before day 30 of pregnancy. Successful embryo development depends on optimal timing of events beginning with ovulation, fertilisation and preparation of the uterine environment for the attachment of the developing embryo. In the pig these processes are tightly controlled and are highly sensitive to disruption. The determinants of optimal early embryo development remain to be fully elucidated but evidence provided in mouse and human studies indicate that constituents of seminal plasma may provide a beneficial ‘priming’ stimulus acting at natural mating to synchronise and enhance early reproductive events. The cytokine transforming growth factor beta (TGFβ) is present in large quantities in mouse and human seminal plasma and is a principal active constituent in mediating seminal fluid signalling in the female reproductive tract. Experiments described in this thesis were designed to investigate whether boar seminal plasma can exert changes in the female reproductive tract during the pre-attachment period in the pig that are comparable to those described in mouse and human. Studies in this thesis demonstrate that seminal plasma causes a transient inflammatory response in the uterus characterised by induction of cytokine gene expression and immune cell changes that occur during the critical period in which the pig embryo is most vulnerable to demise. Seminal factors were also observed to enhance ovarian function...

Prevention of multiple pregnancies in couples with unexplained or mild male subfertility: randomised controlled trial of in vitro fertilisation with single embryo transfer or in vitro fertilisation in modified natural cycle compared with intrauterine insemination with controlled ovarian hyperstimulation

Bensdorp, A.J.; Tjon-Kon-Fat, R.I.; Bossuyt, P.M.M.; Koks, C.A.M.; Oosterhuis, G.J.E.; Hoek, A.; Hompes, P.G.A.; Broekmans, F.J.M.; Verhoeve, H.R.; De Bruin, J.P.; van Golde, R.; Repping, S.; Cohlen, B.J.; Lambers, M.D.A.; van Bommel, P.F.; Slappendel, E.
Fonte: BMJ Publishing Group Publicador: BMJ Publishing Group
Tipo: Artigo de Revista Científica
Publicado em //2015 EN
Relevância na Pesquisa
36.72%
OBJECTIVES: To compare the effectiveness of in vitro fertilisation with single embryo transfer or in vitro fertilisation in a modified natural cycle with that of intrauterine insemination with controlled ovarian hyperstimulation in terms of a healthy child. DESIGN: Multicentre, open label, three arm, parallel group, randomised controlled non-inferiority trial. SETTING: 17 centres in the Netherlands. PARTICIPANTS: Couples seeking fertility treatment after at least 12 months of unprotected intercourse, with the female partner aged between 18 and 38 years, an unfavourable prognosis for natural conception, and a diagnosis of unexplained or mild male subfertility. INTERVENTIONS: Three cycles of in vitro fertilisation with single embryo transfer (plus subsequent cryocycles), six cycles of in vitro fertilisation in a modified natural cycle, or six cycles of intrauterine insemination with ovarian hyperstimulation within 12 months after randomisation. MAIN OUTCOME MEASURES: The primary outcome was birth of a healthy child resulting from a singleton pregnancy conceived within 12 months after randomisation. Secondary outcomes were live birth, clinical pregnancy, ongoing pregnancy, multiple pregnancy, time to pregnancy, complications of pregnancy...

Eficiência da recuperação de embriões e os efeitos de consecutivas colheitas sobre o aparelho reprodutor de doadoras da espécie caprina; Efficiency and effect of consecutive embryo recoveries on the reproductive system of goat donnors

Andrioli, Alice; Simplicio, Aurino Alves; Soares, Adriana Trindade; Visintin, José Antonio
Fonte: Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia Publicador: Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
Publicado em 01/01/1999 POR
Relevância na Pesquisa
36.72%
O objetivo deste experimento foi comparar a eficiência e o efeito de consecutivas colheitas de embriões, por três diferentes métodos (transcervical-T1, laparoscopia-T2 e laparotomia-T3), sobre a atividade reprodutiva de doadoras da espécie caprina. Utilizaram-se 10 cabras em cada método (T1, T2 e T3), sendo as colheitas de embriões repetidas três vezes consecutivas, nas mesmas fêmeas, com intervalo de 56 dias. As fêmeas foram sincronizadas com esponjas vaginais impregnadas com 60 mg de acetato de medroxiprogesterona durante 10 dias e 100 µg de cloprostenol aplicados pela via IM no oitavo dia da sincronização. No 8º dia, iniciou-se a superovulação com 250 UI de FSH de origem suína, divididas em oito doses decrescentes, aplicadas em intervalo de 12 horas. As fêmeas foram acasaladas e as colheitas de embriões realizadas no 5º ou 6º dia após a última cobertura. Após 56 dias da terceira colheita de embriões, foram realizados o abate e a necrópsia das doadoras. O tempo necessário para a colheita de embriões em cada método foi de 21 minutos e 32 segundos; 37 minutos e 14 segundos e 56 minutos e 22 segundos, respectivamente, para T1, T2 e T3 (p<0,01). A maior taxa de recuperação da solução de lavagem foi no T3 (83...