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1.
Hum Reprod ; 34(2): 323-334, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30551136

RESUMO

STUDY QUESTION: Can vitrified baboon ovarian tissue survive >5 months after autotransplantation and subsequently restore fertility? SUMMARY ANSWER: Our results show that ovarian tissue grafts can survive at least 18 months, but fertility restoration could not be confirmed due to lack of pregnancy. WHAT IS KNOWN ALREADY: Ovarian function in baboons can be re-established after autografting of vitrified-warmed ovarian tissue fragments. STUDY DESIGN, SIZE, DURATION: Ovaries from five adult female baboons were used for this study. Unilateral ovariectomy was performed in each animal, followed by vitrification of ovarian fragments. Orthotopic autotransplantation of the vitrified-warmed ovarian fragments was carried out 1 day after ovariectomy. One month later, the other ovary was removed from each animal and vitrified. The next day, the ovarian samples were warmed and orthotopically autografted. Biopsies of grafted tissues were taken after 12 and 18 months for stromal tissue and follicle evaluation. Control samples were collected before vitrification. PARTICIPANTS/MATERIALS, SETTING, METHODS: After grafting, follicle survival, growth and function and also the quality of stromal tissue were assessed histologically and by immunohistochemistry. Estrogen levels were measured, and cyclicity was monitored. All five animals were mated several times. Male baboons used in the mating experiments were not of proven fertility. MAIN RESULTS AND THE ROLE OF CHANCE: After vitrification, warming and long-term grafting, follicles were able to grow. However, their function may have been negatively affected by vitrification and/or transplantation, as expression of kit ligand and c-kit differed from fresh ungrafted tissue (P < 0.05). Corpora lutea and/or ovulation stigma were observed in grafts, indicating successful ovulation in all the baboons, with estrogen levels comparable to those in adult female baboons. LARGE SCALA DATA: Not applicable. LIMITATIONS, REASONS FOR CAUTION: Despite our promising findings on ovarian function restoration, the vitrification procedure could not be validated. Moreover, male baboons used for mating were not of proven fertility. WIDER IMPLICATIONS OF THE FINDINGS: Our protocol of ovarian tissue vitrification successfully re-established ovarian function in a baboon model of autotransplantation. While more studies are required to determine whether this approach can indeed restore fertility, it may prove an easy way of cryopreserving ovarian tissue with a view to recovering ovarian function. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by grants from the Fonds National de la Recherche Scientifique (FNRS) (C.A.A. is an FRS-FNRS Research Associate; grant 5/4/150/5 awarded to M.M.D.), Fonds Spéciaux de Recherche, Fondation Saint Luc, Stichting tegen Kanker (Fondation contre le Cancer), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, Brazil; grant # 013/14 CAPES/WBI awarded to C.M.L.), Wallonie-Bruxelles International (awarded to C.A.A.), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq; grant awarded to Sarah R. Scalercio) and donations from the Ferrero family. None of the authors have any competing interests to declare.


Assuntos
Criopreservação , Sobrevivência de Enxerto , Ovário/transplante , Recuperação de Função Fisiológica , Vitrificação , Animais , Feminino , Seguimentos , Ovariectomia , Ovário/fisiologia , Ovário/cirurgia , Papio anubis , Fatores de Tempo , Transplante Autólogo
2.
Reprod Fertil Dev ; 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25993990

RESUMO

The aim of this study was to evaluate ovarian tissue pre-treatment with 50 µM Trolox followed by heterotopic transplantation in squirrel monkeys (Saimiri collinsi) and to assess tissue functionality via immunohistochemical analysis of the stroma and ovarian follicles. Five healthy and sexually mature squirrel monkey (Saimiri collinsi) females were used. Heterotopic autografting of fresh ovarian tissue with or without previous exposure to the antioxidant Trolox was performed and grafts were recovered for analysis 7 days later. Tissue vascularisation was confirmed by both macroscopic inspection and cluster of differentiation 31 (CD31) staining. Trolox prevented massive follicular activation and kept the percentages of morphologically normal follicles higher than in untreated grafts. Expression of anti-Müllerian hormone in developing follicles was observed only in controls and Trolox-treated grafts. Also, immunostaining for growth differentiation factor-9 was positive only in primordial follicles from controls and from Trolox-treated grafts. Although Trolox improved follicular quality and avoided apoptosis in stromal cells, ovarian tissue fibrosis was increased in Trolox-treated grafts, mainly due to an increase in collagen Type I synthesis.

3.
J Ovarian Res ; 6(1): 83, 2013 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-24274108

RESUMO

BACKGROUND: Although transplantation of cryopreserved ovarian tissue is a promising approach to restore fertility in cancer patients, it is not advisable for women at risk of ovarian involvement due to the threat of reintroducing malignant cells. The aim of this study was therefore to find an alternative for these patients by development of an artificial ovary. METHODS: For construction of the artificial ovary matrix, we used a central composite design to investigate nine combinations of fibrinogen (mg/ml) and thrombin (IU/mL) (F/T): F1/T4, F12.5/T1, F12.5/T20, F25/T0.1, F25/T4, F25/T500, F50/T1, F50/T20 and F100/T4. From the first qualitative analyses (handling and matrix size), five combinations (F12.5/T1, F25/T4, F50/T20, F50/T1 and F100/T4) yielded positive results. They were further evaluated in order to assess fibrin matrix degradation and homogeneous cell encapsulation (density), survival and proliferation (Ki67), and atresia (TUNEL) before and after 7 days of in vitro culture. To determine the best compromise between maximizing the dynamic density (Y1) and minimizing the apoptosis rate (Y2), we used the desirability function approach. RESULTS: Two combinations (F12.5/T1 and F25/T4) showed greater distribution of cells before in vitro culture, reproducible degradation of the fibrin network and adequate support for isolated human ovarian stromal cells, with a high proportion of Ki67-positive cells. SEM analysis revealed a network of fibers with regular pores and healthy stromal cells after in vitro culture with both F/T combinations. CONCLUSION: This study reports two optimal F/T combinations that allow survival and proliferation of isolated human ovarian cells. Further studies are required to determine if such a scaffold will also be a suitable environment for isolated ovarian follicles.

4.
Pesqui. vet. bras ; 33(9): 1144-1150, set. 2013. ilus, graf
Artigo em Inglês | LILACS | ID: lil-694065

RESUMO

This paper aims to describe the uterine and ovarian ultrasonographic characteristics and Doppler velocimetric features of their arteries in bitches during the periovulatory period. Fifteen estrous cycles in 10 animals were evaluated. The ultrasonographic characteristics, resistance indices (RI) and pulsatility indices (PI) of the uterus and ovaries in each animal were recorded 5 days before and after ovulation (D0). The data were statistically analyzed, and the results were expressed as the mean ± standard error of mean (P<0.05). In results the ultrasonographic features of the uterus were the same on all of the cycles and evaluated days. The uterus had an average diameter of 0.85±0.02cm. An increase in the volume of the ovaries and the diameter of the ovarian follicles were measured. Ovaries had a volume of 0.64±0.06cm³, and the follicles cavities had a diameter of 0.46 ± 0.01 cm on the day of ovulation. After ovulation, it was observed that some follicles not collapse in some cycles. Two days prior to ovulation, the uterine blood perfusion decreased. This decrease remained unchanged until ovulation. Following ovulation, we measured a gradual increase in the uterine perfusion and in the ovarian artery. This artery directed blood flow to the ovaries and increased the intra-ovarian perfusion on the day after ovulation. In conclusion, specific features are observed in the uterus and ovarian ultrasound image and Doppler values of their arteries presented on the periovulatory days and when associated allow to estimate more accurately the date of ovulation.


Este trabalho teve como objetivo descrever as características ultrassonográficas uterinas e ovarianas, e dopplervelocimétricas das suas artérias nos dias periovulatórios em cadelas. Quinze ciclos estrais em 10 animais foram avaliados. As características ultrassonográficas, índices de resistência (IR) e índices de pulsatilidade (IP) do útero e dos ovários em cada animal foram registrados 5 dias antes e depois da ovulação (D0). Os dados foram analisados estatisticamente e os resultados foram expressos em média ± erro padrão da média (P<0,05). Como resultados as características ultrassonográficas uterinas foram semelhantes em todos os ciclos e dias avaliados, tendo o corpo uterino um diâmetro médio de 0,85±0,02cm. Foi observado um aumento no volume dos ovários e nos diâmetros dos folículos, tendo os ovários um volume de 0,64±0,06cm³, e a cavidade dos folículos um diâmetro de 0,46±0,01cm no dia da ovulação. Após a ovulação, foi observado colapso dos folículos somente em alguns ciclos. A perfusão sanguínea uterina diminuiu dois dias antes da ovulação e permaneceu inalterada até a ovulação. Após a ovulação, houve um aumento gradual na perfusão das artérias uterinas e ovarianas, direcionando o fluxo de sangue para os ovários e aumentando a perfusão da artéria intra-ovariana um dia após a ovulação. Conclui-se que características específicas são observadas na imagem ultrassonográfica uterina e ovariana, e dopplervelocimétricas de suas artérias nos dias periovulatórios, e quando associadas permitem estimar com mais precisão o dia da ovulação.


Assuntos
Animais , Feminino , Cães , Imagem de Perfusão/veterinária , Ovário/anatomia & histologia , Ultrassonografia Doppler/veterinária , Útero/anatomia & histologia , Artéria Uterina/anatomia & histologia , Ciclo Estral/fisiologia
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