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1.
Zygote ; 30(5): 600-610, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35674131

RESUMO

Despite previous research demonstrating the benefits of including growth factors and antioxidants to maturation medium to support embryo production, to date the effect of epidermal growth factor (EGF) and melatonin (Mel) on oocyte competency has not been studied. This study supplemented in vitro maturation (IVM) medium with EGF (10 ng/ml) and Mel (50 ng/ml) alone, or in combination, and evaluated cumulus cell (CC) gene expression and the development and quality of parthenogenetic blastocysts. No differences in CC gene expression levels indicative of developmental potential were found among the treatment groups. Antioxidant gene CuZnSOD was significantly (P < 0.05) decreased in CCs from the Mel group. Moreover, blastocyst rates on day 7 were significantly increased in EGF or Mel (P < 0.05), but not EGF+Mel. Significant decrease (P < 0.05) in GPX1, CuZnSOD, SLC2A1 and HSPA1A (P = 0.07) mRNA levels was observed in blastocysts from the Mel group. OCT4 gene expression was significantly increased (P < 0.05) in EGF+Mel and confirmed using immunofluorescence. Our results indicate that, despite the lack of changes of competence-related genes in CCs, IVM medium supplemented with Mel improved the culture environment sufficiently, resulting in improved blastocysts. Moreover, EGF and Mel combined during maturation increased OCT4 gene and protein expression in blastocysts, indicating its potential for stem cells.


Assuntos
Células do Cúmulo , Melatonina , Animais , Antioxidantes/metabolismo , Blastocisto , Bovinos , Desenvolvimento Embrionário , Fator de Crescimento Epidérmico/genética , Fator de Crescimento Epidérmico/farmacologia , Feminino , Expressão Gênica , Técnicas de Maturação in Vitro de Oócitos/métodos , Melatonina/farmacologia , Oócitos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
2.
Zygote ; 26(4): 333-335, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30277454

RESUMO

SummaryThe aim of this study was to evaluate the effect of incubating semen for different periods (90, 270 or 450 min) with or without Trolox® (100 or 150 µM) on the quality of sperm from Saimiri collinsi. Sperm motility, vigour, and plasma membrane integrity (PMI) were evaluated in both fresh semen and semen incubated for different time periods, i.e. 90, 270 or 450 min of incubation. Supplementation of semen extender with Trolox® 100 µM improved sperm motility, vigour and PMI for up to 270 min of incubation.


Assuntos
Cromanos/farmacologia , Criopreservação/veterinária , Crioprotetores/farmacologia , Saimiri/fisiologia , Preservação do Sêmen/veterinária , Espermatozoides/fisiologia , Animais , Antioxidantes/farmacologia , Membrana Celular , Masculino , Análise do Sêmen , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos
3.
Reprod Domest Anim ; 52(5): 905-910, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28543808

RESUMO

Cryopreservation causes damage to spermatozoa, and methods minimizing this damage are therefore needed. Although much discussed, seminal plasma removal has become an alternative to improve sperm quality and viability after freezing and has been applied to different species in attempt to obtain good results. The objective of this study was to evaluate semen quality in buffaloes submitted to two methods for seminal plasma removal (filtration and centrifugation). Semen samples were collected from seven Murrah buffalo bulls (Bubalus bubalis) once a week for 8 weeks. Each ejaculate was divided into three groups: control (presence of seminal plasma), centrifugation and filtration. Sperm kinetics was evaluated with the computer-assisted sperm analysis (CASA) system. Plasmalemma and acrosomal membrane integrity, mitochondrial membrane potential and reactive oxygen species (ROS) were measured by flow cytometry, and lipid peroxidation was evaluated by the thiobarbituric acid reactive substances (TBARS) assay. Seminal plasma removal did not improve sperm kinetics compared to the control group. Centrifugation increased the number of cells with damaged acrosomal membranes (0.77 ± 0.05) and filtration caused greater plasmalemma and acrosomal membrane damage (22.18 ± 1.07). No difference in the mitochondrial membrane potential was observed between groups. In contrast, ROS production was higher in the centrifugation group compared to the control and filtration groups, although no differences in TBARS formation were detected. In conclusion, seminal plasma removal did not improve the quality of thawed buffalo semen compared to control in terms of sperm kinetics, membrane integrity, mitochondrial membrane potential or lipid peroxidation.


Assuntos
Búfalos , Criopreservação/veterinária , Preservação do Sêmen/veterinária , Sêmen , Animais , Centrifugação , Criopreservação/métodos , Filtração/veterinária , Masculino , Análise do Sêmen , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides
4.
Anim Genet ; 46(3): 325-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25789691

RESUMO

In this study, we report an approach to characterize individual BoLA haplotypes using cells from parthenogenetic bovine embryos derived from slaughterhouse ovaries. Eight of the 15 parthenogenetic embryos so obtained had not undergone meiotic recombination on the BoLA region and were suitable to describe BoLA haplotypes. Detailed analysis of the BoLA class IIa region identified seven different class IIa haplotypes, including six not previously described and two new alleles of BoLA-DQA and one BoLA-DQB. Our method provided reliable sources of homozygous DNA to describe BoLA haplotypes.


Assuntos
Bovinos/genética , Genes MHC da Classe II , Haplótipos , Alelos , Animais , Embrião de Mamíferos , Partenogênese
5.
Genet Mol Res ; 14(1): 53-62, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25729935

RESUMO

Adult stem cells are known for their plasticity and their potential to differentiate into several different cell types; these characteristics have implications for cell therapy and reproductive biotechnologies. In this study, we report on the isolation and characterization of mesenchymal stem cells (MSC) derived from bovine and buffalo adipose tissue. Cells isolated using enzymatic digestion of bovine and buffalo adipose-tissue biopsy samples were grown in vitro for at least 15 passages, verifying their capacity to proliferate. These cells were also subjected to immunophenotypic characterization for the presence of CD90, CD105, and CD79, and the absence of CD45, CD34, and CD73, which are positive and negative markers of MSC, respectively. To prove their multipotency, the cells were induced to differentiate into three different cell types, chondrocytes, osteoblasts, and adipocytes, which were stained with tissue-specific dyes (Chondrogenic-Alcian Blue, Osteogenic-Alizarin Red, and Adipogenic-Oil-Red O, respectively) to confirm differentiation. Gene expression analysis of pluripotency-related genes was also conducted. Our results suggest that adipose tissue from bovines and buffalos can be used as a source of MSC, making adipose tissue-derived cells an interesting option for cell therapy and regenerative medicine. Additionally, these findings have implications for reproductive biotechnology because the use of MSC as nuclear donors has been linked to an increase in the efficiency of nuclear transfer.


Assuntos
Tecido Adiposo/citologia , Separação Celular/métodos , Células-Tronco Multipotentes/citologia , Adipogenia , Animais , Búfalos , Bovinos , Proliferação de Células , Condrogênese , Imunofenotipagem , Osteogênese
6.
Cell Tissue Res ; 355(2): 471-80, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24362491

RESUMO

Ovarian fragments were exposed to 0.5 M sucrose and 1 M ethylene glycol (freezing solution; FS) with or without selenium or Trolox. Histological and ultrastructural analyses showed that the percentages of normal follicles in control tissue and in tissue after exposure to FS + 50 µM Trolox were similar. Trolox prevented endoplasmic reticulum (ER)-related vacuolization, which is commonly observed in oocytes and stromal tissue after exposure to FS. From the evaluated stress markers, superoxide dismutase 1 (SOD1) was up-regulated in ovarian tissue exposed to FS + 10 ng/ml selenium. Ovarian fragments were subsequently frozen-thawed in the presence of FS with or without 50 µM Trolox, followed by in vitro culture (IVC). Antioxidant capacity in ovarian fragments decreased after freeze-thawing in Trolox-free FS compared with FS + 50 µM Trolox. Although freezing itself minimized the percentage of viable follicles in each solution, Trolox supplementation resulted in higher rates of viable follicles (67 %), even after IVC (61 %). Furthermore, stress markers SOD1 and ERp29 were up-regulated in ovarian tissue frozen-thawed in Trolox-free medium. Relative mRNA expression of growth factors markers was evaluated after freeze-thawing followed by IVC. BMP4, BMP5, CTGF, GDF9 and KL were down-regulated independently of the presence of Trolox in FS but down-regulation was less pronounced in the presence of Trolox. Thus, medium supplementation with 50 µM Trolox prevents ER stress and, consequently, protects ovarian tissue from ER-derived cytoplasmic vacuolization. ERp29 but not ERp60, appears to be a key marker linking stress caused by freezing-thawing and cell vacuolization.


Assuntos
Cebus/metabolismo , Cromanos/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Congelamento , Ovário/efeitos dos fármacos , Ovário/patologia , Vitamina E/análogos & derivados , Animais , Calreticulina/metabolismo , Crioprotetores/farmacologia , Feminino , Proteínas de Choque Térmico HSP70/metabolismo , Ovário/metabolismo , Ovário/ultraestrutura , Superóxido Dismutase/metabolismo
7.
Toxicol In Vitro ; 98: 105847, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38759936

RESUMO

Hydroxychloroquine (HCQ) is a safe antimalarial drug but its overdosage or inappropriate use, such as during the pandemic, may cause adverse effects once this drug is considered a potent inhibitor of autophagy. Information about HCQ's effects on the reproductive field, including gametes and initial embryos, is limited. In this study, we evaluated the effect of HCQ (1, 6, 12, and 24 µM) on pre-implantation embryo development, autophagy, and apoptosis of bovine embryos produced in vitro. A dose-response experiment showed a reduction (p < 0.05) in cleavage only at the highest concentration. Blastocyst rate was gradually reduced (p < 0.05) with the increase of HCQ dosage starting at 6 µM, with no embryo formation occurring at 24 µM. Further analysis showed that embryos treated with 12 µM of HCQ had a higher (p < 0.05) accumulation of acidic autophagic vesicles on Days 5 and 7 of development and a higher (p < 0.01) apoptotic index on Day 7. To our knowledge, this is the first study to evaluate the effects of HCQ on embryo pre-implantation development in mammals. The results contribute with more information related to the study of autophagy in embryology as well as add some discussion on HCQ toxicology and its effects on reproductive cells.


Assuntos
Apoptose , Autofagia , Blastocisto , Desenvolvimento Embrionário , Hidroxicloroquina , Animais , Bovinos , Hidroxicloroquina/toxicidade , Desenvolvimento Embrionário/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Blastocisto/efeitos dos fármacos , Feminino , Antimaláricos/toxicidade , Fertilização in vitro , Técnicas de Cultura Embrionária
8.
Zygote ; 21(2): 167-71, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22475447

RESUMO

There is no tradition in studies reporting the effect of exposure to cryoprotectants or simply hypoxia and hypothermia on gene expression in the ovarian tissue and there has been only one study on reference or target genes quantification, and comparisons of normoxic with hypoxic, hypothermic and toxic conditions. Our aim in the present study was to investigate the stability of three reference genes in the ovarian tissue of capuchin monkeys (Cebus apella). To this end, fresh and cryoprotectant-exposed ovarian biopsies were used. Both fresh and exposed ovarian tissues were subjected to total RNA extraction and synthesis of cDNA. cDNA was amplified by real-time polymerase chain reaction (PCR), and GeNorm, BestKeeper and NormFinder software were used to evaluate the stability of glyceraldehyde-2-phosphate dehydrogenase (GAPDH), hypoxanthine phosphoribosyltransferase 1 (HPRT1) and TATA-binding protein (TBP). Results demonstrated that, in the ovarian tissue from capuchin monkeys, HPRT1 and TBP were the most suitable reference genes and thus could be used as parameters to normalize data in future studies. In contrast, GAPDH appeared as the least stable gene among the tested reference genes. In conclusion, HPRT1 and TBP were the most stable reference genes in fresh and cryoprotectant-exposed ovarian tissue from capuchin monkeys.


Assuntos
Gliceraldeído-3-Fosfato Desidrogenases/genética , Hipoxantina Fosforribosiltransferase/genética , Ovário/efeitos dos fármacos , Padrões de Referência , Proteína de Ligação a TATA-Box/genética , Animais , Cebus , Crioprotetores/farmacologia , Feminino , Hipotermia , Ovário/citologia , Ovário/metabolismo , Oxigênio/farmacologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Reprod Domest Anim ; 46(1): e17-22, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20403125

RESUMO

The objective of this study was to determine the number, morphology and ultrastructure of preantral ovarian follicles of buffalo (Bubalus bubalis) foetuses at different ages. Quantification revealed number of primordial, primary and secondary follicles of 48,857 ± 17,506, 26,000 ± 20,452, 18,428 ± 10,875 and 18,375 ± 19,690, 225 ± 349, 326 ± 288 at 12-34 cm and 35-60 cm crown rump length (CRL), respectively. Follicular diameter values were 28.9 (± 3.4), 34.7 (± 5.9) and 59.4 (± 12.6) µm; oocyte diameters were 21.7 (± 2.8), 24.3 (± 3.4) and 33.0 (± 7.7) µm, and the numbers of follicular cells in the follicle equatorial section were 7.1 (± 1.4), 12.0 (± 2.4) and 13.8 (± 2.4) for primordial, primary and secondary follicles, respectively. The primordial follicle consisted of an oocyte surrounded by a layer of flattened follicular cells with a normally eccentric oocyte nucleus. Dispersed Golgi complex, smooth endoplasmic reticulum, rounded mitochondria and several lipid vesicles were observed in the cytoplasm and cell junctions between the follicle cell membranes and the oocyte. This work describes the number, morphometry and ultrastructure of preantral follicles of buffalo foetuses, concluding that folliculogenesis is established between 8 and 34 cm CRL and that follicle number varies individually and according to age and that further studies are needed in this species.


Assuntos
Búfalos/embriologia , Folículo Ovariano/embriologia , Animais , Núcleo Celular/ultraestrutura , Citoplasma/ultraestrutura , Feminino , Idade Gestacional , Microscopia Eletrônica de Varredura/veterinária , Microscopia Eletrônica de Transmissão/veterinária , Oócitos/ultraestrutura , Folículo Ovariano/ultraestrutura
10.
Oper Dent ; 36(6): 678-82, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21864123

RESUMO

The aim of this study was to describe a technique and report the success of a clinical case in which a modified technique of in-office bleaching with hydrogen peroxide at 35% was performed for two sessions in a premolar pigmented by amalgam followed by placement of a posterior direct composite resin restoration.


Assuntos
Amálgama Dentário/efeitos adversos , Clareamento Dental/métodos , Descoloração de Dente/etiologia , Descoloração de Dente/terapia , Adulto , Dente Pré-Molar , Corrosão , Feminino , Humanos , Peróxido de Hidrogênio/administração & dosagem , Retratamento , Clareadores Dentários/administração & dosagem
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