Base de dados : MEDLINE
Pesquisa : A16.166 [Categoria DeCS]
Referências encontradas : 2191 [refinar]
Mostrando: 1 .. 10   no formato [Detalhado]

página 1 de 220 ir para página                         

  1 / 2191 MEDLINE  
              next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28449669
[Au] Autor:Gleicher N; Metzger J; Croft G; Kushnir VA; Albertini DF; Barad DH
[Ad] Endereço:The Center for Human Reproduction, 21 East 69th Street, New York, NY, 10021, USA. ngleicher@thechr.com.
[Ti] Título:A single trophectoderm biopsy at blastocyst stage is mathematically unable to determine embryo ploidy accurately enough for clinical use.
[So] Source:Reprod Biol Endocrinol;15(1):33, 2017 Apr 27.
[Is] ISSN:1477-7827
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: It has become increasingly apparent that the trophectoderm (TE) at blastocyst stage is much more mosaic than has been appreciated. Whether preimplantation genetic screening (PGS), utilizing a single TE biopsy (TEB), can reliably determine embryo ploidy has, therefore, increasingly been questioned in parallel. METHODS: We for that reason here established 2 mathematical models to assess probabilities of false-negative and false-positive results of an on average 6-cell biopsy from an approximately 300-cell TE. This study was a collaborative effort between investigators at The Center for Human Reproduction in New York City and the Center for Studies in Physics and Biology and the Brivanlou Laboratory of Stem Cell Biology and Molecular Embryology, the latter two both at Rockefeller University in New York City. RESULTS: Both models revealed that even under best case scenario, assuming even distribution of mosaicism in TE (since mosaicism is usually clonal, a highly unlikely scenario), a biopsy of at least 27 TE cells would be required to reach minimal diagnostic predictability from a single TEB. CONCLUSIONS: As currently performed, a single TEB is, therefore, mathematically incapable of reliably determining whether an embryo can be transferred or should be discarded. Since a single TEB, as currently performed, apparently is not representative of the complete TE, this study, thus, raises additional concern about the clinical utilization of PGS.
[Mh] Termos MeSH primário: Blastocisto
Fase de Clivagem do Zigoto
Ectoderma/patologia
Ploidias
Diagnóstico Pré-Implantação/métodos
Trofoblastos/patologia
[Mh] Termos MeSH secundário: Aneuploidia
Biópsia
Blastocisto/metabolismo
Blastocisto/patologia
Fase de Clivagem do Zigoto/metabolismo
Fase de Clivagem do Zigoto/patologia
Implantação do Embrião/genética
Feminino
Seres Humanos
Modelos Teóricos
Gravidez
Diagnóstico Pré-Implantação/normas
Reprodutibilidade dos Testes
[Pt] Tipo de publicação:EVALUATION STUDIES; JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170429
[St] Status:MEDLINE
[do] DOI:10.1186/s12958-017-0251-8


  2 / 2191 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28887017
[Au] Autor:Henry JQ; Lyons DC; Perry KJ; Osborne CC
[Ad] Endereço:University of Illinois, Department of Cell&Developmental Biology, 601 S. Goodwin Ave., Urbana, IL 61801, United States. Electronic address: j-henry4@illinois.edu.
[Ti] Título:Establishment and activity of the D quadrant organizer in the marine gastropod Crepidula fornicata.
[So] Source:Dev Biol;431(2):282-296, 2017 11 15.
[Is] ISSN:1095-564X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:During development in metazoan embryos, the fundamental embryonic axes are established by organizing centers that influence the fates of nearby cells. Among the spiralians, a large and diverse branch of protostome metazoans, studies have shown that an organizer sets up the dorsal-ventral axis, which arises from one of the four basic cell quadrants during development (the dorsal, D quadrant). Studies in a few species have also revealed variation in terms of how and when the D quadrant and the organizer are established. In some species the D quadrant is specified conditionally, via cell-cell interactions, while in others it is specified autonomously, via asymmetric cell divisions (such as those involving the formation of polar lobes). The third quartet macromere (3D) typically serves as the spiralian organizer; however, other cells born earlier or later in the D quadrant lineage can serve as the organizer, such as the 2d micromere in the annelid Capitella teleta or the 4d micromere in the mollusc Crepidula fornicata. Here we present work carried out in the snail C. fornicata to show that establishment of a single D quadrant appears to rely on a combination of both autonomous (via inheritance of the polar lobe) and conditional mechanisms (involving induction via the progeny of the first quartet micromeres). Through systematic ablation of cells, we show that D quadrant identity is established between 5th and 6th cleavage stages, as it is in other spiralians that use conditional specification. Subsequently, following the next cell cycle, organizer activity takes place soon after the birth of the 4d micromere. Therefore, unlike the case in other spiralians that use conditional specification, the specification of the D quadrant and the activity of the dorso-ventral organizer are temporally and spatially uncoupled. We also present data on organizer function in naturally-occurring and experimentally-induced twin embryos, which possess multiple D quadrants. We show that supernumerary D quadrants can arise in C. fornicata (either spontaneously or following polar lobe removal); when multiple D quadrants are present these do not exhibit effective organizer activity. We conclude that the polar lobe is not required for D quadrant specification, though it could play a role in effective organizer activity. We also tested whether the inheritance of the small polar lobe by the D quadrant is associated with the ability to laterally inhibit neighboring quadrants by direct contact in order to normally prevent supernumerary organizers from arising. Finally, we discuss the variation of spiralian organizers in a phylogenetic context.
[Mh] Termos MeSH primário: Organismos Aquáticos/citologia
Organismos Aquáticos/crescimento & desenvolvimento
Gastrópodes/citologia
Gastrópodes/embriologia
Organizadores Embrionários/citologia
Organizadores Embrionários/embriologia
[Mh] Termos MeSH secundário: Animais
Fase de Clivagem do Zigoto/citologia
Embrião não Mamífero/citologia
Embrião não Mamífero/metabolismo
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171111
[Lr] Data última revisão:
171111
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170910
[St] Status:MEDLINE


  3 / 2191 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28847488
[Au] Autor:Fawzy M; Emad M; AbdelRahman MY; Abdelghafar H; Abdel Hafez FF; Bedaiwy MA
[Ad] Endereço:IbnSina IVF Center, IbnSina Hospital, Sohag, Egypt. Electronic address: drfawzy001@me.com.
[Ti] Título:Impact of 3.5% O culture on embryo development and clinical outcomes: a comparative study.
[So] Source:Fertil Steril;108(4):635-641, 2017 Oct.
[Is] ISSN:1556-5653
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:OBJECTIVE: To evaluate the effect of culturing human embryos in vitro in 3.5% oxygen (O ) concentration. DESIGN: Comparative study. SETTING: Private IVF center. PATIENT(S): The study included 558 women in two groups. INTERVENTION(S): After intracytoplasmic sperm injection (ICSI), women's oocytes were assigned to undergo cultivation in either 3.5% O concentration (intervention) or 5% O level (control group), continuously, from day 0 through day 5 or 6. MAIN OUTCOME MEASURE(S): Clinical pregnancy rate (PR) after ET. RESULT(S): There were significantly higher fertilization and cleavage rates in the 3.5% O group (odds ratio [OR] 1.72, 95% confidence interval [CI] 1.53-1.93) and (OR 3.74, 95% CI 2.30-6.07) than in the 5% O group. The compaction rate on day 3, and the number of formed, high-quality and cryopreserved blastocysts on day 5 were significantly lower in 3.5% O than in 5% O concentration ([OR 0.81, 95% CI 0.69-0.91], [OR 0.40, 95% CI 0.36-0.46], [OR 0.32, 95% CI 0.28-0.37] and [OR 0.47, 95% CI 0.40-0.54]), respectively. Culturing embryos in 3.5% O concentration led to significantly lower rates of biochemical pregnancy, clinical PR, and implantation ([OR 0.66, 95% CI 0.47-0.92], [OR 0.60, 95% CI 0.43-0.84] and [OR 0.61, 95% CI 0.46-0.81]), respectively. CONCLUSION(S): Culturing human embryos, continuously from day 0 to 5 or 6, in 3.5% O concentration is associated with significantly lower blastocyst formation rate and clinical outcomes parameters, but rather with significantly higher rates of fertilization and cleavage. Whether these findings hold true for other patient populations and culture media brands remain unknown.
[Mh] Termos MeSH primário: Blastocisto/efeitos dos fármacos
Técnicas de Cultura Embrionária/métodos
Desenvolvimento Embrionário/efeitos dos fármacos
Oxigênio/farmacologia
[Mh] Termos MeSH secundário: Adulto
Blastocisto/citologia
Blastocisto/fisiologia
Células Cultivadas
Fase de Clivagem do Zigoto/citologia
Fase de Clivagem do Zigoto/efeitos dos fármacos
Meios de Cultura/química
Meios de Cultura/farmacologia
Transferência Embrionária
Feminino
Seres Humanos
Masculino
Oxigênio/administração & dosagem
Gravidez
Taxa de Gravidez
Injeções de Esperma Intracitoplásmicas
[Pt] Tipo de publicação:COMPARATIVE STUDY; EVALUATION STUDIES; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Culture Media); S88TT14065 (Oxygen)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171013
[Lr] Data última revisão:
171013
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170830
[St] Status:MEDLINE


  4 / 2191 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28432218
[Au] Autor:Auman T; Vreede BMI; Weiss A; Hester SD; Williams TA; Nagy LM; Chipman AD
[Ad] Endereço:Department of Ecology, Evolution and Behavior, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram 91904, Jerusalem, Israel.
[Ti] Título:Dynamics of growth zone patterning in the milkweed bug .
[So] Source:Development;144(10):1896-1905, 2017 05 15.
[Is] ISSN:1477-9129
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:We describe the dynamic process of abdominal segment generation in the milkweed bug We present detailed morphological measurements of the growing germband throughout segmentation. Our data are complemented by cell division profiles and expression patterns of key genes, including and as markers for different stages of segment formation. We describe morphological and mechanistic changes in the growth zone and in nascent segments during the generation of individual segments and throughout segmentation, and examine the relative contribution of newly formed versus existing tissue to segment formation. Although abdominal segment addition is primarily generated through the rearrangement of a pool of undifferentiated cells, there is nonetheless proliferation in the posterior. By correlating proliferation with gene expression in the growth zone, we propose a model for growth zone dynamics during segmentation in which the growth zone is functionally subdivided into two distinct regions: a posterior region devoted to a slow rate of growth among undifferentiated cells, and an anterior region in which segmental differentiation is initiated and proliferation inhibited.
[Mh] Termos MeSH primário: Padronização Corporal
Heterópteros/embriologia
[Mh] Termos MeSH secundário: Animais
Padronização Corporal/genética
Divisão Celular/genética
Proliferação Celular/genética
Fase de Clivagem do Zigoto/metabolismo
Embrião não Mamífero
Regulação da Expressão Gênica no Desenvolvimento
Heterópteros/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171126
[Lr] Data última revisão:
171126
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170423
[St] Status:MEDLINE
[do] DOI:10.1242/dev.142091


  5 / 2191 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28421493
[Au] Autor:Edgar DH; Archer J; Gook DA
[Ad] Endereço:Reproductive Services/Melbourne IVF and Department of Obstetrics & Gynaecology, University of Melbourne, Royal Women's Hospital, Cnr Grattan Street and Flemington Road, Parkville, VIC, 3052, Australia. david.edgar@mivf.com.au.
[Ti] Título:Chapter 9 Slow Freezing and Thawing of Human Cleavage Stage Embryos.
[So] Source:Methods Mol Biol;1568:119-129, 2017.
[Is] ISSN:1940-6029
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The ability to store human embryos in a viable state at very low temperatures has been critical to the evolution of responsible practice in clinical Assisted Reproductive Technology (ART). It has encouraged a reduction in the frequency of simultaneous multiple embryo transfer and thereby reduced the risks associated with multiple pregnancy while maintaining high cumulative pregnancy rates from single oocyte collection cycles. In this chapter, we describe a simple slow freezing procedure for human early cleavage stage embryos that results in a high proportion of post-thaw embryos surviving and retaining their implantation potential.
[Mh] Termos MeSH primário: Fase de Clivagem do Zigoto
Criopreservação/métodos
Embrião de Mamíferos
[Mh] Termos MeSH secundário: Sobrevivência Celular
Fase de Clivagem do Zigoto/citologia
Criopreservação/instrumentação
Crioprotetores
Implantação do Embrião
Embrião de Mamíferos/citologia
Feminino
Seres Humanos
Gravidez
Taxa de Gravidez
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cryoprotective Agents)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170531
[Lr] Data última revisão:
170531
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170420
[St] Status:MEDLINE
[do] DOI:10.1007/978-1-4939-6828-2_9


  6 / 2191 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28325473
[Au] Autor:Charney RM; Forouzmand E; Cho JS; Cheung J; Paraiso KD; Yasuoka Y; Takahashi S; Taira M; Blitz IL; Xie X; Cho KW
[Ad] Endereço:Department of Developmental and Cell Biology, Ayala School of Biological Sciences, University of California, Irvine, CA 92697, USA.
[Ti] Título:Foxh1 Occupies cis-Regulatory Modules Prior to Dynamic Transcription Factor Interactions Controlling the Mesendoderm Gene Program.
[So] Source:Dev Cell;40(6):595-607.e4, 2017 Mar 27.
[Is] ISSN:1878-1551
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The interplay between transcription factors and chromatin dictates gene regulatory network activity. Germ layer specification is tightly coupled with zygotic gene activation and, in most metazoans, is dependent upon maternal factors. We explore the dynamic genome-wide interactions of Foxh1, a maternal transcription factor that mediates Nodal/TGF-ß signaling, with cis-regulatory modules (CRMs) during mesendodermal specification. Foxh1 marks CRMs during cleavage stages and recruits the co-repressor Tle/Groucho in the early blastula. We highlight a population of CRMs that are continuously occupied by Foxh1 and show that they are marked by H3K4me1, Ep300, and Fox/Sox/Smad motifs, suggesting interplay between these factors in gene regulation. We also propose a molecular "hand-off" between maternal Foxh1 and zygotic Foxa at these CRMs to maintain enhancer activation. Our findings suggest that Foxh1 functions at the top of a hierarchy of interactions by marking developmental genes for activation, beginning with the onset of zygotic gene expression.
[Mh] Termos MeSH primário: Endoderma/metabolismo
Fatores de Transcrição Forkhead/metabolismo
Regulação da Expressão Gênica no Desenvolvimento
Mesoderma/metabolismo
Fatores de Transcrição/metabolismo
Proteínas de Xenopus/metabolismo
Xenopus/embriologia
Xenopus/genética
[Mh] Termos MeSH secundário: Animais
Blástula/metabolismo
Fase de Clivagem do Zigoto/metabolismo
Proteínas Correpressoras/metabolismo
Embrião não Mamífero/metabolismo
Endoderma/embriologia
Elementos Facilitadores Genéticos/genética
Fatores de Transcrição Forkhead/genética
Genoma
Histonas/metabolismo
Lisina/metabolismo
Mesoderma/embriologia
Metilação
Proteína Nodal/metabolismo
Ligação Proteica/genética
RNA Polimerase II/metabolismo
RNA Mensageiro/genética
RNA Mensageiro/metabolismo
Sequências Reguladoras de Ácido Nucleico/genética
Análise de Sequência de RNA
Transdução de Sinais/genética
Transcrição Genética
Xenopus/metabolismo
Proteínas de Xenopus/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Co-Repressor Proteins); 0 (FOXH1 protein, Xenopus); 0 (Forkhead Transcription Factors); 0 (Histones); 0 (Nodal Protein); 0 (RNA, Messenger); 0 (Transcription Factors); 0 (Xenopus Proteins); EC 2.7.7.- (RNA Polymerase II); K3Z4F929H6 (Lysine)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170619
[Lr] Data última revisão:
170619
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170323
[St] Status:MEDLINE


  7 / 2191 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28228320
[Au] Autor:Desch L; Bruno C; Luu M; Barberet J; Choux C; Lamotte M; Schmutz E; Sagot P; Fauque P
[Ad] Endereço:Laboratoire de Biologie de la Reproduction, Hôpital François Mitterrand, Université de Bourgogne, Dijon, France.
[Ti] Título:Embryo multinucleation at the two-cell stage is an independent predictor of intracytoplasmic sperm injection outcomes.
[So] Source:Fertil Steril;107(1):97-103.e4, 2017 Jan.
[Is] ISSN:1556-5653
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:OBJECTIVE: To determine the prognostic impact of the nuclear status at the two-cell stage on intracytoplasmic sperm injection (ICSI) outcomes. DESIGN: Retrospective study. SETTING: Hospital. PATIENT(S): Only ICSI cycles with time-lapse monitoring of transferred embryos with known implantation/delivery data from November 2012 to December 2014 were included. A total of 2,449 embryos were assessed for multinucleation rates at the two- and four-cell stage, and 608 transferred embryos were studied for ICSI outcomes. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Implantation rate (IR) and live birth rate (LBR) according to the number of multinucleated blastomeres at the two-cell stage: none (Without-MNB ), one (MNB ), and two (MNB ); morphokinetics of MNB embryos. RESULT(S): Embryos with MNB led to lower IR (27.7%) and LBR (22.7%) than embryos Without-MNB (33.4% and 29.8%, respectively). The MNB embryos led to significantly lower IR (18.3%) and LBR (13.4%) than embryos Without-MNB . This difference remained significant in multivariate analysis for implantation (odds ratio 0.57; 95% confidence interval 0.34-0.94) and birth (odds ratio 0.46; 95% confidence interval 0.26-0.80), independently of the other significant parameters (women's age, time of two-cell formation, and multinucleation at the four-cell stage). Among implanted MNB , if cleavage into four cells occurred later than 37 hours after insemination, embryos were significantly more likely to lead to birth. CONCLUSION(S): The presence of multinucleation at the two-cell stage and more specifically in both blastomeres had a significant negative impact on birth potential. Thus, embryo multinucleation at the two-cell stage should be used as an additional noninvasive criterion for embryo selection.
[Mh] Termos MeSH primário: Blastômeros/citologia
Núcleo Celular
Embrião de Mamíferos/citologia
Infertilidade/terapia
Injeções de Esperma Intracitoplásmicas/efeitos adversos
[Mh] Termos MeSH secundário: Distribuição de Qui-Quadrado
Fase de Clivagem do Zigoto
Implantação do Embrião
Transferência Embrionária/efeitos adversos
Feminino
Fertilidade
Seres Humanos
Infertilidade/diagnóstico
Infertilidade/fisiopatologia
Nascimento Vivo
Modelos Logísticos
Microscopia de Vídeo
Análise Multivariada
Razão de Chances
Gravidez
Taxa de Gravidez
Estudos Retrospectivos
Fatores de Risco
Imagem com Lapso de Tempo/métodos
Resultado do Tratamento
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170714
[Lr] Data última revisão:
170714
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170224
[St] Status:MEDLINE


  8 / 2191 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28151020
[Au] Autor:Liu L; Cai J; Li P; Jiang X; Ren J
[Ad] Endereço:a Reproductive Medicine Center, Affiliated Chenggong Hospital of Xiamen University , Xiamen , Fujian , China.
[Ti] Título:Clinical outcome of cycles with oocyte degeneration after intracytoplasmic sperm injection.
[So] Source:Syst Biol Reprod Med;63(2):113-119, 2017 Apr.
[Is] ISSN:1939-6376
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:There are variant rates of oocyte degeneration after intracytoplasmic sperm injection (ICSI) among different patients. Oocyte degeneration after ICSI may reflect the cohort of oocyte quality and subsequent embryo development capacity and clinical outcome. This retrospective study analyzed 255 cycles with at least one degenerated oocyte after ICSI (degeneration group) and 243 cycles with no degenerated oocytes after ICSI (control group). Basic characteristics like female age, body mass index, duration of infertility, hormone (FSH, LH, E ) levels on day 3 of menses, and primary infertility patient rate were similar between the two groups (p > 0.05). Total dose of gonadotropin and length of stimulation were also similar between the two groups (p > 0.05), but the degeneration group exhibited a more exuberant response to ovarian stimulation as reflected by more oocytes retrieved (p < 0.05). The number of 2PN embryos available and high quality embryos were similar between the two groups (p > 0.05), but the high quality embryo rate, early cleavage embryo rate, and available embryo rate were all statistically lower than the control group (p < 0.05). Embryo developmental kinetics seemed to be disturbed and embryo fragmentation rate increased in the degeneration group (p < 0.05). However, there was no statistical difference in the distribution of graded embryos transferred, and there were no statistical differences in the pregnancy rate, implantation rate, and abortion rate between the two groups (p > 0.05). We deduce that the presence of oocyte degeneration after ICSI may be associated with decreased embryo quality with embryo development kinetics disturbed. However, the clinical outcomes may not be affected if the premise that sufficient high quality degeneration group embryos are available for transfer.
[Mh] Termos MeSH primário: Fertilidade
Infertilidade/terapia
Oócitos/patologia
Injeções de Esperma Intracitoplásmicas
[Mh] Termos MeSH secundário: Aborto Espontâneo/etiologia
Adulto
Blastocisto/patologia
Fase de Clivagem do Zigoto/patologia
Técnicas de Cultura Embrionária
Implantação do Embrião
Transferência Embrionária
Desenvolvimento Embrionário
Feminino
Fármacos para a Fertilidade Feminina/uso terapêutico
Seres Humanos
Infertilidade/patologia
Infertilidade/fisiopatologia
Cinética
Masculino
Recuperação de Oócitos
Oócitos/efeitos dos fármacos
Indução da Ovulação
Gravidez
Taxa de Gravidez
Estudos Retrospectivos
Injeções de Esperma Intracitoplásmicas/efeitos adversos
Resultado do Tratamento
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fertility Agents, Female)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170807
[Lr] Data última revisão:
170807
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170203
[St] Status:MEDLINE
[do] DOI:10.1080/19396368.2016.1272648


  9 / 2191 MEDLINE  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo
[PMID]:28043361
[Au] Autor:Ochota M; Nizanski W
[Ad] Endereço:Department of Reproduction and Clinic of Farm Animals, Wroclaw University of Environmental and Life Sciences, Faculty of Veterinary Medicine, Wroclaw, Poland. Electronic address: malgorzata.ochota@up.wroc.pl.
[Ti] Título:Time of early cleavage affects the developmental potential of feline preimplantation embryos in vitro.
[So] Source:Theriogenology;89:26-31, 2017 Feb.
[Is] ISSN:1879-3231
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The study compared developmental competence of embryos, based on the timing of the first cleavage and morula formation, with their subsequent ability to reach the blastocyst stage and the resulting blastocyst morphology and quality. Cleaved embryos were separated at 18 hours post insemination (hpi), 24 hpi, and 30 hpi and then cultured in droplets to follow the individual embryo development. The significantly higher percentage of the blastocyst formation was noted in the group I of embryos cleaving within less than 18 hpi (12.7%) compared with the group II cleaving within 18 to 24 hpi (10.7%), None of the late-cleaving embryos (group III >24-30 hpi) reached blastocyst stage in our experiment. Interestingly, the hatching ability was similar regardless the time of the first cleavage (I: <18 hpi; 6.4% and II: 18-24 hpi; 5.4%). The ability to hatch was correlated with the time of morula formation; only embryos that reached morula on Day 4 or Day 5 were able to develop into hatching blastocyst (8.4% and 3.3%, respectively). The differential cell staining revealed significantly more blastomeres in blastocysts obtained from embryos cleaving within 18 to 24 hpi than the blastocysts obtained from embryos cleaving less than 18 hpi (188.6 ± 21.9 vs. 129.3 ± 16). Embryos cleaving within 18 to 24 hpi also demonstrated the higher number and percentage of embryoblast cells (97.2 ± 12.6, 51.6 ± 2.9 vs. 46.6 ± 9, 36.3 ± 6.6). The presented results confirmed the association among the onset of the first cleavage, time reaching morula, and subsequent blastocyst formation and quality.
[Mh] Termos MeSH primário: Blastocisto/fisiologia
Gatos/embriologia
Desenvolvimento Embrionário/fisiologia
Fertilização In Vitro/veterinária
[Mh] Termos MeSH secundário: Animais
Fase de Clivagem do Zigoto/fisiologia
Feminino
Masculino
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170926
[Lr] Data última revisão:
170926
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170104
[St] Status:MEDLINE


  10 / 2191 MEDLINE  
              first record previous record
seleciona
para imprimir
Fotocópia
[PMID]:27975272
[Au] Autor:Hasley A; Chavez S; Danilchik M; Wühr M; Pelegri F
[Ad] Endereço:Laboratory of Genetics, University of Wisconsin-Madison, Genetics/Biotech Addition, Room 2424, 425-G Henry Mall, Madison, WI, 53706, USA.
[Ti] Título:Vertebrate Embryonic Cleavage Pattern Determination.
[So] Source:Adv Exp Med Biol;953:117-171, 2017.
[Is] ISSN:0065-2598
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The pattern of the earliest cell divisions in a vertebrate embryo lays the groundwork for later developmental events such as gastrulation, organogenesis, and overall body plan establishment. Understanding these early cleavage patterns and the mechanisms that create them is thus crucial for the study of vertebrate development. This chapter describes the early cleavage stages for species representing ray-finned fish, amphibians, birds, reptiles, mammals, and proto-vertebrate ascidians and summarizes current understanding of the mechanisms that govern these patterns. The nearly universal influence of cell shape on orientation and positioning of spindles and cleavage furrows and the mechanisms that mediate this influence are discussed. We discuss in particular models of aster and spindle centering and orientation in large embryonic blastomeres that rely on asymmetric internal pulling forces generated by the cleavage furrow for the previous cell cycle. Also explored are mechanisms that integrate cell division given the limited supply of cellular building blocks in the egg and several-fold changes of cell size during early development, as well as cytoskeletal specializations specific to early blastomeres including processes leading to blastomere cohesion. Finally, we discuss evolutionary conclusions beginning to emerge from the contemporary analysis of the phylogenetic distributions of cleavage patterns. In sum, this chapter seeks to summarize our current understanding of vertebrate early embryonic cleavage patterns and their control and evolution.
[Mh] Termos MeSH primário: Evolução Biológica
Divisão Celular/genética
Desenvolvimento Embrionário/genética
Vertebrados/embriologia
[Mh] Termos MeSH secundário: Animais
Ciclo Celular/genética
Fase de Clivagem do Zigoto/metabolismo
Regulação da Expressão Gênica no Desenvolvimento
Mamíferos
Fuso Acromático/genética
Vertebrados/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.; REVIEW
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170916
[Lr] Data última revisão:
170916
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161216
[St] Status:MEDLINE



página 1 de 220 ir para página                         
   


Refinar a pesquisa
  Base de dados : MEDLINE Formulário avançado   

    Pesquisar no campo  
1  
2
3
 
           



Search engine: iAH v2.6 powered by WWWISIS

BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde