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1.
Cryobiology ; 84: 95-97, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30125538

RESUMO

We evaluated the effects of the vitrification solution (i.e., ethylene glycol (EG) + dimethyl sulfoxide (DMSO) with or without propylene glycol (PG)) and of exposure time on the re-expansion and hatching rates of vitrified Bos indicus embryos. In vitro produced embryos (n = 1050) were divided into seven groups: control group (non-vitrified embryos) and six vitrification groups with different cryoprotectant concentrations and exposure times. After vitrification, embryos were cultured for determination of re-expansion and hatching rates. Vitrification with 25% DMSO +25% EG (exposure for 1 min and 20 s) resulted in the highest re-expansion (65.2%) and hatching (68.2%) rates. The lowest re-expansion and hatching rates were observed in vitrification with 12.5% DMSO + 25% EG + 12.5% PG with both tested exposure times (i.e., 3 min + 1 min and 1 min + 20 s). A combination of DMSO + EG is efficient to preserve blastocysts, especially following a short exposure time.


Assuntos
Blastocisto/efeitos dos fármacos , Criopreservação/métodos , Crioprotetores/farmacologia , Vitrificação , Animais , Bovinos , Dimetil Sulfóxido/farmacologia , Etilenoglicol/farmacologia , Feminino , Fertilização In Vitro , Propilenoglicol/farmacologia
2.
Reprod Fertil Dev ; 30(2): 359-370, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28768567

RESUMO

The aim of this study was to evaluate the viability, antrum formation and in vitro development of isolated secondary follicles from vitrified caprine ovarian cortex in a medium previously established for fresh isolated secondary follicles, in the absence (α-minimum essential medium (α-MEM+) alone) or presence of FSH and vascular endothelial growth factor (VEGF; α-MEM++FSH+VEGF). Ovarian fragments were distributed among five treatments (T1 to T5): fresh follicles were fixed immediately (T1), follicles from fresh tissue were cultured in vitro in α-MEM+ (T2) or α-MEM++FSH+VEGF (T3) and follicles from vitrified tissue were cultured in vitro in α-MEM+ (T4) or α-MEM++FSH+VEGF (T5). After 6 days of culture, treated follicles (T2, T3, T4 and T5) were evaluated for morphology, viability and follicular development (growth, antrum formation and proliferation of granulosa cells by Ki67 and argyrophilic nucleolar organiser region (AgNOR) staining). The levels of reactive oxygen species (ROS) in the culture media were also assessed. Overall, morphology of vitrified follicles was altered (P<0.05) compared with the fresh follicles. Follicular viability, antrum formation and ROS were similar between treatments (P>0.05). The average overall and daily follicular growth was highest (P<0.05) in T3. Granulosa cells in all treatments (T1, T2, T3, T4 and T5) stained positive for Ki67. However, fresh follicles from T3 had significantly higher AgNOR staining (P<0.05) compared with follicles of T1, T2, T4 and T5. In conclusion, secondary follicles can be isolated from vitrified and warmed ovarian cortex and survive and form an antrum when growing in an in vitro culture for 6 days.


Assuntos
Criopreservação/veterinária , Cabras/embriologia , Técnicas de Maturação in Vitro de Oócitos/veterinária , Folículo Ovariano/fisiologia , Ovário/citologia , Animais , Antígenos Nucleares/metabolismo , Proliferação de Células , Forma Celular , Sobrevivência Celular , Células Cultivadas , Feminino , Fármacos para a Fertilidade Feminina/farmacologia , Hormônio Foliculoestimulante/farmacologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/farmacologia
3.
Reprod Fertil Dev ; 30(3): 459-468, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28784201

RESUMO

The aim of the present study was to evaluate the development of fresh and vitrified agouti ovarian tissue after xenografting to C57Bl/6 severe combined immunodeficiency (SCID) female mice. Ovaries were obtained from five female agoutis and divided into 16 fragments. Five fragments were transplanted immediately to ovariectomised SCID mice and the others were vitrified, stored for 2 weeks and transplanted only after rewarming. Tissue fragments were transplanted under the kidney capsule in recipients. The return of ovarian activity in recipients was monitored by the observation of external signs of oestrus and vaginal cytology over a period of 40 days after transplantation, after which the grafts were removed and evaluated for morphology, cell proliferation and the occurrence of DNA fragmentation. Ovarian activity returned in four of five mice that received fresh ovarian tissue from agoutis and in one of six mice that had received vitrified tissue a mean (±s.e.m.) 20.6±8.6 days after xenotransplantation. After graft removal, a predominance of primordial and primary follicles was observed in all grafts. Vitrification reduced cell proliferation and increased the occurrence of DNA fragmentation in grafted agouti ovarian tissue. In conclusion, the present study demonstrates that xenografted agouti ovarian tissue, fresh or vitrified, is able to promote the return of ovarian activity in ovariectomised SCID C57B1/6 mice. However, improvements to vitrification protocols for agouti ovarian tissue are necessary.


Assuntos
Criopreservação , Preservação da Fertilidade/métodos , Ovariectomia , Ovário/transplante , Animais , Proliferação de Células , Fragmentação do DNA , Ciclo Estral , Feminino , Sobrevivência de Enxerto , Xenoenxertos , Camundongos Endogâmicos C57BL , Camundongos SCID , Ovário/metabolismo , Ovário/patologia , Gravidez , Recuperação de Função Fisiológica , Fatores de Tempo , Vitrificação
4.
Reprod Fertil Dev ; 29(3): 594-602, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28442066

RESUMO

The aim of the present study was to characterise the ovarian preantral follicle (PF) population and to establish a solid surface vitrification (SSV) process using dimethyl sulfoxide (DMSO) as a cryoprotectant for preservation of ovarian tissue from yellow-toothed cavies (Galea spixii). Ovaries were fixed for PF population analysis or were subjected to the SSV process. The mean (± s.e.m.) PF population per ovarian pair was estimated to be 416.0±342.8. There were 140.0±56.0 (63.4%) and 125.0±58.0 (64.0%) primary follicles on the right and left ovaries, respectively. The proportion of this follicle category was significantly greater than that of other follicle categories (P<0.05). The diameter of follicles (123.7±18.3µm), oocytes (50.1±5.0µm) and nuclei (14.27±2.01µm) was larger for secondary ones when compared with other PFs categories. Most PFs were morphologically normal (94.6%), with light microscopy identifying only a few atretic follicles (5.4%). After SSV, there was a reduction in the proportion of morphologically normal PFs compared with the non-vitrified group (69.5% vs 91.2%, respectively). Transmission electron microscopy revealed preservation of oocytes and granulosa cell membranes and the morphological aspect of follicles; the primary change observed in some vitrified PFs was the presence of vacuoles in the oocytes and granulosa cells cytoplasm and turgid mitochondria. In conclusion, the present study provides an estimative and characterization for the PF population in ovaries of G. spixii. Moreover, we report its PFs cryopreservation using an SSV process.


Assuntos
Criopreservação , Folículo Ovariano/anatomia & histologia , Ovário/anatomia & histologia , Vitrificação , Animais , Feminino , Microscopia Eletrônica de Transmissão , Folículo Ovariano/ultraestrutura , Ovário/ultraestrutura , Roedores
6.
Biopreserv Biobank ; 6(4): 269-76, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24835524

RESUMO

The aim of the present study was to determine the amount of dimethyl sulfoxide (DMSO) present in sheep ovarian tissue after exposure to cryoprotectant at different times (5, 10, 20, or 30 min) and at different concentrations (1.0, 1.5, or 2.0 M). To quantify the levels of DMSO in the ovarian tissue, the high-performance liquid chromatography (HPLC) method was applied. In addition, viability of preantral follicles after toxicity test and cryopreservation of ovarian tissue using the above mentioned concentrations of DMSO and exposure times was evaluated. We have observed that the presence of ∼0.6 mg of DMSO into the ovarian tissue may be deleterious to the sheep preantral follicles. In addition, the application of a short exposure time (5 min at 1.5 or 2.0 M DMSO) or low concentration (1.0 M for 10 min) of DMSO successfully preserves sheep preantral follicles following cryopreservation.

7.
Anim Reprod Sci ; 99(1-2): 53-64, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-16787716

RESUMO

Isolated or cortical tissue-enclosed (in situ) sheep early-stage follicles were exposed to 1.5 M dimethyl sulfoxide (DMSO), ethylene glycol (EG) or unexposed, or frozen/thawed in the presence of these cryoprotectants and then cultured for 5 days in enriched minimal essential medium (MEM) or not cultured. Cultured and uncultured follicles were classified as non-viable/viable when they were stained/not stained with trypan blue, respectively. Follicular diameter was measured and the percentages of primordial and developing follicles calculated. Exposure of isolated or in situ follicles to DMSO or EG led to a marked decrease in the percentage of viable follicles. The percentage of viable isolated and in situ follicles further decreased when they were in vitro-cultured for 5 days, EG-exposed follicles generally showing a more damaging effect than DMSO-exposed follicles. Cultured follicles, both isolated and in situ, which were exposed to EG and DMSO, as well as in situ follicles, which had been frozen/thawed in the presence of one of these cryoprotectants, showed similar growth rates as cultured, untreated follicles, while in these groups significantly lower percentages of primordial follicles and higher percentages of more advanced follicular stages were observed. Among the treated groups, the highest percentage (71-75%) of developing follicles was observed after culturing cryoprotectant-exposed isolated follicles. In contrast, when cryopreserved, isolated follicles were cultured, they did not increase in diameter and did not develop into more advanced stages. In conclusion, exposure to or cryopreservation in the presence of EG and DMSO, as well as their further in vitro culture, negatively affected the viability of ovine isolated and in situ early-stage follicles. In vitro growth of early-stage follicles and activation of primordial follicles were better maintained when follicles had been frozen/thawed and cultured in situ.


Assuntos
Criopreservação/veterinária , Folículo Ovariano/fisiologia , Ovinos/fisiologia , Animais , Crioprotetores/toxicidade , Dimetil Sulfóxido/toxicidade , Etilenoglicol/toxicidade , Feminino , Folículo Ovariano/citologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/crescimento & desenvolvimento , Fatores de Tempo , Azul Tripano/metabolismo
8.
Anim Reprod Sci ; 91(3-4): 249-63, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15985344

RESUMO

The aim of this study was to verify the histological and ultrastructural characteristics of sheep preantral follicles after exposure of ovarian tissue to cryopreservation in glycerol (GLY), ethylene glycol (EG), propanediol (PROH) or dimethyl sulfoxide (DMSO) in order to determine the optimum method to store sheep ovarian tissue for later experimental or clinical use. Each ovarian pair from five mixed-breed ewes was divided into 17 fragments. One (control) fragment was immediately fixed for routine histological and ultrastructural studies and the remaining (test) fragments were randomly distributed in cryotubes, equilibrated at 20 degrees C/20 min in 1.8 mL of minimal essential medium (MEM) containing 1.5 or 3 M GLY, EG, PROH or DMSO and then either fixed for morphological studies to determine their possible toxic effect or frozen/thawed and then fixed to test the effect of cryopreservation on preantral follicles. Histological analysis showed that, compared to control fragments, all cryoprotectants at both concentrations significantly reduced the percentage of normal preantral follicles in ovarian fragments prior to or after cryopreservation. PROH 3.0 M appeared to exert a more toxic effect (P<0.05) than the other cryoprotectants in noncryopreserved tissues. After freezing/thawing, the highest (P<0.05) percentages of lightmicroscopical normal preantral follicles were observed in ovarian fragments cryopreserved in EG (1.5 and 3 M) or DMSO (1.5 M). However, transmission electronic microscopical (TEM) examination showed that only the DMSO-cryopreserved preantral follicles had normal ultrastructure. The data suggest that sheep preantral follicles should be cryopreserved with 1.5 M DMSO for later clinical or experimental application.


Assuntos
Criopreservação/veterinária , Crioprotetores , Folículo Ovariano/ultraestrutura , Ovinos , Preservação de Tecido/veterinária , Animais , Núcleo Celular/ultraestrutura , Citoplasma/ultraestrutura , Dimetil Sulfóxido , Etilenoglicol , Feminino , Glicerol , Temperatura Alta , Microscopia Eletrônica , Ovário/ultraestrutura , Propilenoglicóis
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