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1.
Gynecol Obstet Invest ; 75(3): 157-62, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23391858

RESUMO

BACKGROUND: Ovarian tissue cryopreservation by vitrification is an attractive technique for fertility preservation in women. However, this technique has not been optimized. The aim of this study was to evaluate the baboon as a model for the preclinical study of ovarian tissue cryopreservation by vitrification and thawing. METHODS: Ovarian cortical tissues (1-mm cubes) were obtained surgically from adult female olive baboons (n = 9) maintained in captivity and vitrified using dimethyl sulphoxide and ethylene glycol protocol. The proportion of morphologically intact follicles (primordial, primary and secondary) in paired fresh and cryopreserved (vitrified-thawed) ovarian tissues was compared. RESULTS: Overall, 67.1% of follicles were morphologically normal after vitrification. When compared to fresh ovarian tissue, vitrified-thawed ovarian tissue contained a comparable number of intact primordial follicles (48.9 vs. 52.9%), and a lower number of both primary (14.8 vs. 29.5%; p < 0.05) and secondary (2.0 vs. 0.7%; p < 0.05) follicles. CONCLUSION: After vitrification and thawing, baboon ovarian tissue retains about 67% of morphologically normal follicles, which is comparable to results for human ovarian tissue, and suggests that the olive baboon is a promising animal model for preclinical assessment of ovarian vitrification, thawing and autotransplantation studies.


Assuntos
Criopreservação/métodos , Preservação de Órgãos/métodos , Ovário , Vitrificação , Animais , Criopreservação/normas , Feminino , Preservação da Fertilidade/métodos , Modelos Animais , Folículo Ovariano , Papio anubis , Projetos Piloto
2.
Semin Reprod Med ; 30(3): 191-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22585630

RESUMO

Since 2004, assisted conception is encompassed by the European Directive on the Quality and Safety of Tissues and Cells (2004/23/EC). The aim of a standard for quality and safety is to minimize risks of errors, contamination, and accidents and to maximize efficiency of use. This article presents a case study of the implementation of the Tissues and Cells Directive in the Leuven University Fertility Center (LUFC) with a focus on the assisted reproductive technologies laboratory with respect to laboratory facilities, quality management system, traceability, storage conditions as well as serological screening. Although the current European Union (EU) Directive can be considered a step in the right direction to improve patient safety, questions remain as to whether the implementation of this EU Directive, requiring extra time and money, has resulted in higher quality with respect to the quality dimensions of effectiveness, efficiency, timeliness, equity, and patient centeredness.


Assuntos
Laboratórios/normas , Segurança do Paciente/normas , Técnicas de Reprodução Assistida/normas , Bancos de Tecidos/normas , Bélgica , Análise Custo-Benefício , União Europeia , Hospitais , Humanos , Controle de Qualidade
3.
Reprod Biol Endocrinol ; 9: 127, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21920032

RESUMO

BACKGROUND: Quality control programs are necessary to maintain good clinical practice. Embryo grading has been described as one of the external quality assurance schemes. Although the evaluation of embryos is based on the assessment of morphological characteristics, considerable intra- and inter-observer variability has been described. In this multicentre study, the variability in the embryo evaluation has been evaluated using morphological characteristics on day 1, day 2 and day 3 of embryo development. METHODS: Five embryologists of four different IVF centers participated in this study. Multilevel images of embryos were presented on a website at different time points to evaluate intra-and inter-observer agreement in the assessment of embryo morphology. The embryos were evaluated on day 1, day 2 and day 3 of their development and each embryologist had to decide if the embryo had to be transferred, cryopreserved or discarded. RESULTS: Both intra-observer agreement and inter-observer agreement were good to excellent for the position of the pronuclei on day 1, the number of blastomeres on day 2 and day 3 and the clinical decision (transfer, cryopreservation, discard). For all other characteristics (size of pronuclei, presence of cytoplasomic halo, degree of fragmentation and size of blastomeres) the intra- and inter-observer agreement was moderate to very poor. CONCLUSIONS: Mono- or multicentre quality control on embryo scoring by morphological assessment can easily be performed through the design of a simple website. In the future the website design can be adapted to generate statistical feedback upon scoring and can even include a training module.


Assuntos
Blastocisto/ultraestrutura , Tomada de Decisões Assistida por Computador , Desenvolvimento Embrionário , Fertilização in vitro , Blastômeros/citologia , Núcleo Celular/ultraestrutura , Tamanho Celular , Citoplasma/ultraestrutura , Embrião de Mamíferos/ultraestrutura , Embriologia , Humanos , Internet , Variações Dependentes do Observador , Controle de Qualidade , Reprodutibilidade dos Testes , Recursos Humanos , Zigoto/ultraestrutura
4.
Gynecol Obstet Invest ; 67(2): 127-33, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19005260

RESUMO

BACKGROUND/AIMS: Some embryo implantation problems in patients with recurrent implantation failure may be explained by the inability of the embryo to hatch out of its zona pellucida. In this case-control study, a study group which had received modified quarter laser-assisted zona thinning (mQLAZT) was compared with a control group which had not received mQLAZT with respect to reproductive outcome. METHODS: Cycles from patients with a 4th fresh embryo transfer (ET) after 3 previously failed ET cycles (no beta-hCG detected) were included. Cases (group A, n = 53) included ET cycles from patients who received a 4th ET with fresh embryos after mQLAZT. Controls (group B, n = 86) included ET cycles from patients who had a 4th ET without mQLAZT. The clinical implantation rate and live birth rate per embryo transferred were measured. RESULTS: The clinical implantation rate with positive fetal heart beat per embryo transferred was significantly higher (p = 0.035) in group A (22/107 or 21%) than in group B (18/166 or 11%). CONCLUSION: The data of this case-control study suggest that mQLAZT can be effective in the treatment of patients with recurrent implantation failure, but need to be confirmed by randomized trials.


Assuntos
Transferência Embrionária/métodos , Transferência Embrionária/estatística & dados numéricos , Terapia a Laser/métodos , Taxa de Gravidez , Zona Pelúcida , Adulto , Estudos de Casos e Controles , Terapia Combinada , Implantação do Embrião , Transferência Embrionária/efeitos adversos , Feminino , Seguimentos , Humanos , Infertilidade Feminina/diagnóstico , Infertilidade Feminina/terapia , Gravidez , Resultado da Gravidez , Prevalência , Probabilidade , Valores de Referência , Retratamento , Estudos Retrospectivos , Medição de Risco , Resultado do Tratamento
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