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1.
J Mol Histol ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39249549

RESUMO

Conservation of the genetic diversity through skin and cartilage biobanks represents an essential strategy for maintaining biodiversity. Biobanks for the wild species of the order Rodentia have been little studied. Considering that the cryopreservation technique has specific relationships with the tissue and species of interest, we propose investigating different techniques for preserving tissue integrity and cell viability after cartilage and skin culture from Spix's yellow-toothed cavies. Subsequently, two techniques [solid-surface vitrification (SSV) vs. slow freezing (SF)] were used for cartilage and skin cryopreservation. Tissues not subjected to cryopreservation were used as controls. All tissues were evaluated for morphology and proliferation by histological techniques. Moreover, fragments were cultured, and cells were evaluated for viability, proliferation, metabolism, and apoptosis. Regardless of the cryopreservation technique, no differences were observed for the thickness of the epidermis, dermis, skin, spinous and basal layers, fibroblasts, and proliferative activity regarding the number of nucleolar organizer regions (NOR). SSV ensured better maintenance of epidermal cells, normal chondrocytes, filled gaps, collagen fibers, proliferative activity by NOR area/cell, and reduced perinuclear halos and empty gaps compared to SF. SF ensured the conservation of corneum thickness compared to the control. Although both techniques promoted cell recovery after culture, cells from SF resulted in better subconfluence time and day with cell growth around fragments compared to SSV. In conclusion, both cryopreservation techniques resulted in viable cells after culture. However, SSV promoted better maintenance of tissue morphological integrity, and SF ensured the preservation of all cell quality parameters in Spix's yellow-toothed cavies.

2.
JBRA Assist Reprod ; 28(3): 497-502, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-38838161

RESUMO

Ovarian tissue cryopreservation and transplantation (OTCT) has emerged in recent years as a potential method for reversing abnormal endocrine and reproductive functions, particularly in patients receiving gonadotoxic cancer treatments having longer survival rates. From its first rodent experiments to human trials, OTCT has evolved tremendously, opening new windows for further utilization. Since then, significant progress has been achieved in terms of techniques used for surgical removal of the tissue, optimal fragment size, freezing and thawing procedures, and appropriate surgical sites for the subsequent reimplementation of the graft. In addition, various approaches have been proposed to decrease the risk of ischemic injury, which is the leading cause of significant follicle loss during neo-angiogenesis. This review aims to discuss the pros and cons of ovarian and retroperitoneal transplantation sites, highlighting the justifications for the viability and efficacy of different transplantation sites as well as the potential advantages and drawbacks of retroperitoneal or preperitoneal area.


Assuntos
Criopreservação , Preservação da Fertilidade , Ovário , Humanos , Feminino , Ovário/transplante , Criopreservação/métodos , Preservação da Fertilidade/métodos , Espaço Retroperitoneal/cirurgia
3.
JBRA Assist Reprod ; 27(3): 579-581, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-36749815

RESUMO

OBJECTIVE: Cryopreservation techniques are used to preserve fertility before cancer treatment with gonadotoxic agents. Herein, we report a case of fertility preservation involving a 29-year-old G0P0 woman, married for one year, who was referred to our hospital for fertility preservation before starting rectal cancer treatment. CASE DESCRIPTION: Ovarian tissue and embryo cryopreservation were performed. Before the procedure, ovarian reserve was evaluated, and antral follicle counts were determined. Laparoscopic ovarian tissue cryopreservation was performed from the left side with a lower antral follicle count. Thus, we were able to keep the number of oocytes obtained in the following controlled ovarian hyperstimulation cycle at the highest level. Subsequently, the right ovary was transposed into the lateral wall of the abdomen under the peritoneum. Conventionally controlled ovarian hyperstimulation was initiated on the first postoperative day, depending on the menstrual cycle phase. Intracytoplasmic sperm injection was performed on four mature oocytes obtained, and one embryo was cryopreserved. Controlled ovarian hyperstimulation was initiated on the first postoperative day, and the process was repeated on the seventh postoperative day, yielding a total of seven viable embryos for cryopreservation. CONCLUSIONS: There is usually only one chance of controlled ovarian hyperstimulation in patients requiring a fertility-sparing approach due to malignancy. In the combined technique, performing ovarian tissue resection from the ovary with a lower number of antral follicles can keep the number of oocytes at the highest level in the following controlled ovarian hyperstimulation cycle.


Assuntos
Preservação da Fertilidade , Síndrome de Hiperestimulação Ovariana , Neoplasias Retais , Masculino , Feminino , Humanos , Adulto , Preservação da Fertilidade/métodos , Sêmen , Criopreservação/métodos , Oócitos/fisiologia , Neoplasias Retais/complicações , Neoplasias Retais/cirurgia
4.
Cryobiology ; 103: 116-122, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34464611

RESUMO

Piracanjunba (Brycon orbignyanus) is an endangered South American fish, and ovarian tissue cryopreservation is an alternative method for preserving maternal germplasm and genetic diversity. Therefore, our aim was to test a vitrification protocol for ovarian tissue containing primary growth (PG) oocytes of B. orbignyanus as a strategy to avoid the threat of extinction. Two vitrification solutions were evaluated (VS1: 1.5 M methanol + 4.5 M propylene glycol and VS2: 1.5 M methanol + 5.5 M Me2SO) and compared using control/fresh ovarian tissue. After vitrification, the following factors were analyzed: membrane integrity using trypan blue, morphology using a histological assessment, oxidative stress (total reactive antioxidant potential (TRAP) and reduced thiol [-SH]), mitochondrial activity using MTT, and DNA damage using a comet assay. The vitrified oocytes (VS1 = 24.3 ± 0.49% and VS2 = 24.8 ± 0.69%) showed higher DNA damage than the control group (control = 20.7 ± 1.03%) (P = 0.004). In contrast, in most evaluations (membrane integrity, membrane damage, oxidative stress, and mitochondrial activity), there were no discernible differences between the control group and the vitrified samples. In addition, oocyte (P = 0.883) and nuclear diameter (P = 0.118) did not change after vitrification. VS2 treatment resulted in higher nuclear damage (15.7 ± 1.45%) than in the control treatment (3.5 ± 1.19%); however, VS1 treatment did not result in significantly more damage (9.5 ± 3.01%) than in the control (P = 0.015). Therefore, the protocol for ovarian tissue vitrification tested in this study resulted in high maintenance of PG oocyte cell integrity, making it a promising alternative for B. orbignyanus maternal genome preservation.


Assuntos
Caraciformes , Vitrificação , Animais , Criopreservação/métodos , Feminino , Oócitos , Ovário
5.
Zoo Biol ; 40(4): 280-287, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33739467

RESUMO

Biological resource banks represent valuable tools for the conservation of species vulnerable to extinction, such as the jaguar. Cryobanks of skins have the potential to safeguard rare genotypes, allowing the potential exploitation of biological samples in animal multiplication technologies and the study of genetic variability. Determination of the most suitable skin regions for tissue conservation can help increase the efficiency of cryobanks and the storage of biological samples. To this end, we evaluated the effects of vitrification of skin tissues from the ear, caudal, and femoral regions of a post-mortem jaguar belonging to a zoo in Brazil. Non-vitrified and vitrified samples were evaluated and compared using quantitative methods, focusing on skin thickness, cell quantification, number of perinuclear halos, collagen and elastic density, and proliferative activity. No differences were observed in skin thickness, number of perinuclear halos, elastic density, and proliferative activity between non-vitrified and vitrified tissues in skin from any region. However, vitrified tissues derived from femoral skin showed a reduction in the number of fibroblasts, epidermal cells and collagen density compared to non-vitrified tissues. In summary, the ear and caudal regions provided the best conservation of somatic tissues derived from jaguars, and skin samples from these regions are therefore the most suitable for the formation of cryobanks.


Assuntos
Criopreservação/veterinária , Panthera/fisiologia , Fenômenos Fisiológicos da Pele , Pele/anatomia & histologia , Manejo de Espécimes , Vitrificação , Animais , Orelha , Cauda
6.
Biopreserv Biobank ; 18(3): 235-243, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32282240

RESUMO

Systematic cryo-banking of reproductive tissues could enhance reproductive management and ensure sustainability of rare mammalian genotypes. Testicular tissues contain a vast number of germ cells, including at early stages (spermatogonia and spermatocytes), that can potentially develop into viable spermatozoa after grafting or culture in vitro, and the resulting sperm cells then can be used for assisted reproductive techniques. The objective of this review was to describe current advances, limitations, and perspectives related to the use of testicular tissue preservation as a strategy for the conservation of male fertility. Testes can be obtained from mature or prepubertal individuals, immediately postmortem or by orchiectomy, but testicular biopsies could also be an alternative to collect samples from living individuals. Testicular fragments can be then cryopreserved by using slow or ultra-rapid freezing, or even vitrification methods. The composition of cryopreservation media can vary according to species-specific characteristics, especially regarding the cryoprotectant type and concentration. Finally, spermatozoa have been usually obtained after xenografting of testicular fragments into severely immunodeficient mice, while this method still has to be optimized after in vitro culture conditions.


Assuntos
Criopreservação/métodos , Testículo/citologia , Técnicas de Cultura de Tecidos/métodos , Animais , Biópsia , Humanos , Masculino , Camundongos , Testículo/cirurgia , Testículo/transplante , Transplante Heterólogo
7.
Cryobiology ; 91: 53-60, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31678072

RESUMO

The objective was to evaluate different permeating cryoprotectants to vitrify testicular tissue biopsies from adult collared peccaries. Five pairs of testicles were dissected into fragments (9 mm³) that were allocated to non-vitrified (control) and vitrified groups using a solid-surface method following exposure to different cryoprotectants (3.0 M dimethyl sulfoxide (DMSO), 3.0 M ethylene glycol (EG) or 1.5 M DMSO + 1.5 M EG). After warming, samples were evaluated for histomorphology, ultrastructure, viability, and proliferative capacity potential. The appropriate conservation of the ultrastructural organization of the seminiferous tubule in terms of lumen presence and cell junctions was only observed at the use of DMSO/EG combination. Regardless of the cryoprotectant, the vitrification effectively preserved cell nuclear visualization and condensation similarly as observed at the non-vitrified group. Moreover, DMSO/EG combination provided a better preservation of basal membranes of seminiferous tubules than DMSO (P < 0.05). The occurrence of cell swelling was more evident in the use of DMSO than EG (P < 0.05), but both isolate cryoprotectants were similar to the DMSO/EG combination. Only the DMSO/EG combination maintained the proliferative capacity potential for spermatogonia (3.69 NORs/cell) and Sertoli cell (3.19 NORs/cell) similar to controls (3.46 and 3.31 NORS/cell, respectively). Moreover, ~40% cell viability was found after vitrification independent of cryoprotectant. In conclusion, DMSO/EG in combination is better than DMSO or EG alone for SSV of testicular tissue biopsies from adult collared peccaries.


Assuntos
Criopreservação/veterinária , Crioprotetores/farmacologia , Dimetil Sulfóxido/farmacologia , Etilenoglicol/farmacologia , Testículo/citologia , Animais , Artiodáctilos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Criopreservação/métodos , Crioprotetores/química , Feminino , Masculino , Vitrificação
8.
Rev Urol ; 17(4): 211-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26839518

RESUMO

Approximately 0.2% of Americans aged 20 to 39 years are childhood cancer survivors. Advances in cancer detection and therapy have greatly improved survival rates for young cancer patients; however, treatment of childhood cancers can adversely impact reproductive function. Many cancer patients report a strong desire to be informed of existing options for fertility preservation and future reproduction prior to initiation of gonadotoxic cancer therapies, including surgery, chemotherapy, and radiotherapy. This article discusses, in detail, the effects of cancer treatment on fertility in men and women, and outlines both current and experimental methods of fertility preservation among cancer patients.

9.
JBRA Assist Reprod ; 18(1): 16-23, 2014 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-35761719

RESUMO

Malignant and cardiovascular diseases are the main causes of death in Brazil. Estimates for 2013 predict the occurrence of 189,150 new cases of cancer in Brazilian women. With advanced detection tools, patients are diagnosed and treated for cancer at a younger age and are more likely to survive. The cytotoxic action of chemotherapeutic agents and radiotherapy very frequently implies serious damage to the gonads, and consequences due to the hypoestrogenism, such as osteoporosis, infertility and premature ovarian failure, are expected. Oncofertility, then, appears as a new area of reproductive medicine, which is dedicated to the development of strategies for the reduction of therapeutic sequels in cancer survivals, ultimately aiming the maintenance of their quality of life and the possibility of biological maternity. This article aims to present an overview of possible options for female fertility preservation after cancer and future perspectives in oncofertility.

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