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1.
Anim. Reprod. (Online) ; 19(2): e20220036, mai. 2022. graf, tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1393185

Resumo

Infertility is one of the most prevalent health disorders in reproductive-age males and females. Ficus carica (Fc), an herbal plant, has been used traditionally for the treatment of different diseases such as infertility especially in Iranian folk medicine. This study examined the effects of Fc leaf extract on the proliferation of mice spermatogonial stem cells (SSCs). Phenolic, flavonoid content, major polyphenolic compounds and antioxidant activity of the extract was evaluated respectively by Folin-Ciocateu, aluminum chloride, HPLC and the FRAP and DPPH methods. Testicular cells of neonate mice were extracted and their identity was confirmed using cytokeratin for Sertoli and Oct-4, CDHI and PLZF for SSCs. Effects of Fc (0.0875, 0.175, 0.35, 0.71 and 1.42 mg/ml) was evaluated at third, 7th, 9th and 14th days of culture by colony assay. The expression of the Mvh, GFRα1 and Oct-4 genes and the viability and proliferation of cultured cells was assessed at the end of the culture period. The extract has a rich phenolic and flavonoid content such as Rutin, Psoralen, Bergapten and Caffeoylmalic acid using HPLC analysis. It also had a potent reducing and radical scavenging activity. Morphology of colonies was similar in all groups. Higher viability, proliferation, colony number and diameter of SSCs was seen in the presence of Fc leaf extract in a dosedependent manner so that higher number and diameter of colonies were observed in two higher doses of 0.71 and 1.42 mg/ml, separately for each time point relative to other groups. The Mvh, Oct-4 and GFRα1 genes expression had no significant differences between groups. It seems that Fc leaf extract not only had no any cytotoxic effects on the viability and proliferation of SSCs but also support their stemness state. So, this culture system can be employed for enrichment of germ stem cells for use in clinical applications.(AU)


Assuntos
Animais , Camundongos , Extratos Vegetais/efeitos adversos , Ficus/efeitos adversos , Camundongos/embriologia , Citotoxicidade Imunológica , Células-Tronco Germinativas Adultas/citologia
2.
Anim. Reprod. (Online) ; 16(3): 508-523, 2019. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1461460

Resumo

The veterinary and animal science professions are rapidly developing and their inherent and historical connection to agriculture is challenged by more biomedical and medical directions of research. While some consider this development as a risk of losing identity, it may also be seen as an opportunity for developing further and more sophisticated competences that may ultimately feed back to veterinary and animal science in a synergistic way. The present review describes how agriculture-related studies on bovine in vitro embryo production through studies of putative bovine and porcine embryonic stem cells led the way to more sophisticated studies of human induced pluripotent stem cells (iPSCs) using e.g. gene editing for modeling of neurodegeneration in man. However, instead of being a blind diversion from veterinary and animal science into medicine, these advanced studies of human iPSC-derived neurons build a set of competences that allowed us, in a more competent way, to focus on novel aspects of more veterinary and agricultural relevance in the form of porcine and canine iPSCs. These types of animal stem cells are of biomedical importance for modeling of iPSC-based therapy in man, but in particular the canine iPSCs are also important for understanding and modeling canine diseases, as e.g. canine cognitive dysfunction, for the benefit and therapy of dogs.


Assuntos
Animais , Células-Tronco Pluripotentes Induzidas , Embrião de Mamíferos , Oócitos , Pesquisa Biomédica
3.
Anim. Reprod. ; 16(3): 508-523, 2019. ilus
Artigo em Inglês | VETINDEX | ID: vti-22363

Resumo

The veterinary and animal science professions are rapidly developing and their inherent and historical connection to agriculture is challenged by more biomedical and medical directions of research. While some consider this development as a risk of losing identity, it may also be seen as an opportunity for developing further and more sophisticated competences that may ultimately feed back to veterinary and animal science in a synergistic way. The present review describes how agriculture-related studies on bovine in vitro embryo production through studies of putative bovine and porcine embryonic stem cells led the way to more sophisticated studies of human induced pluripotent stem cells (iPSCs) using e.g. gene editing for modeling of neurodegeneration in man. However, instead of being a blind diversion from veterinary and animal science into medicine, these advanced studies of human iPSC-derived neurons build a set of competences that allowed us, in a more competent way, to focus on novel aspects of more veterinary and agricultural relevance in the form of porcine and canine iPSCs. These types of animal stem cells are of biomedical importance for modeling of iPSC-based therapy in man, but in particular the canine iPSCs are also important for understanding and modeling canine diseases, as e.g. canine cognitive dysfunction, for the benefit and therapy of dogs.(AU)


Assuntos
Animais , Oócitos , Embrião de Mamíferos , Pesquisa Biomédica , Células-Tronco Pluripotentes Induzidas
4.
R. bras. Reprod. Anim. ; 43(2): 315-326, abr.-jun. 2019. tab
Artigo em Português | VETINDEX | ID: vti-21819

Resumo

As biotecnologias para produção de embriões in vivo e in vitro são de grande importância para acelerar o ganho genético dos rebanhos de corte e de leite. No entanto, o sucesso desses processos depende diretamente da quantidade e da qualidade dos oócitos da doadora de embrião. Diversos fatores influenciam a produção de embriões como a população folicular, a idade da doadora, o estresse térmico, o status metabólico e o status reprodutivo. Na atualidade, vários estudos têm sido desenvolvidos para elaborar estratégias que contornem estes desafios e aumentem a eficiência das técnicas de produção de embriões. Dentre os tratamentos estabelecidos para melhorar a produção de embriões das doadoras destacam-se a utilização de FSH, rBST, propilenoglicol e células tronco mesenquimais.(AU)


Biotechnologies for producing in vivo and in vitro embryos are very important to accelerate the genetic gain of beef and dairy herds. However, the success of these processes depend directly on the quantity and quality of the donors oocytes. Many factors influence the embryo production, such as follicle population, age, heat stress, metabolic status and reproductive status. Recently, many studies have been conducted to elaborate strategies that can overcome these issues and increase the efficiency of the embryo production techniques. Among the treatments developed to improve the embryo production, the use of FSH, rBST, propylene glycol and mesenchymal stem cells stand out.(AU)


Assuntos
Animais , Masculino , Bovinos , Embrião de Mamíferos , Bovinos/embriologia , Melhoramento Genético , Transferência Embrionária/veterinária
5.
Rev. bras. reprod. anim ; 43(2): 315-326, abr.-jun. 2019. tab
Artigo em Português | VETINDEX | ID: biblio-1492584

Resumo

As biotecnologias para produção de embriões in vivo e in vitro são de grande importância para acelerar o ganho genético dos rebanhos de corte e de leite. No entanto, o sucesso desses processos depende diretamente da quantidade e da qualidade dos oócitos da doadora de embrião. Diversos fatores influenciam a produção de embriões como a população folicular, a idade da doadora, o estresse térmico, o status metabólico e o status reprodutivo. Na atualidade, vários estudos têm sido desenvolvidos para elaborar estratégias que contornem estes desafios e aumentem a eficiência das técnicas de produção de embriões. Dentre os tratamentos estabelecidos para melhorar a produção de embriões das doadoras destacam-se a utilização de FSH, rBST, propilenoglicol e células tronco mesenquimais.


Biotechnologies for producing in vivo and in vitro embryos are very important to accelerate the genetic gain of beef and dairy herds. However, the success of these processes depend directly on the quantity and quality of the donors oocytes. Many factors influence the embryo production, such as follicle population, age, heat stress, metabolic status and reproductive status. Recently, many studies have been conducted to elaborate strategies that can overcome these issues and increase the efficiency of the embryo production techniques. Among the treatments developed to improve the embryo production, the use of FSH, rBST, propylene glycol and mesenchymal stem cells stand out.


Assuntos
Masculino , Animais , Bovinos , Bovinos/embriologia , Embrião de Mamíferos , Melhoramento Genético , Transferência Embrionária/veterinária
6.
Semina Ci. agr. ; 40(1): 225-238, Jan.-Feb. 2019. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-19427

Resumo

The agouti has been used as an experimental model in several studies focused on reproductive biology. The umbilical cord, an embryonic attachment that connects the foetus to the placenta, has been reported as an important anatomical site for obtaining stem cells. The objective of this study was to describe macro- and microscopically the umbilical cord of agoutis at different stages of gestation, to expand and cultivate in vitro the progenitor cells and to report their morphological characteristics. Seven cutias were submitted to caesarean section to collect the umbilical cords: five were destined for studies of cord structure in different stages of gestation (30, 35, 50, 75 and 100 days postcoital), and two were collected in the third stage of gestation for isolation and cell culture. The umbilical cord of cutias assumes a spiral arrangement, with veins and arteries on it starting 50 days after coitus. The arteries present an outer layer of smooth muscle fibres in a longitudinal and circular arrangement and a medium layer of smooth muscle fibres with only longitudinal and intimate orientation and coated by the endothelium. The veins consist of longitudinal smooth muscle fibres with an extract of smooth muscle cells, and the endothelium, in all analysed gestational phases, is a structure bounded by simple pavement epithelial tissue originating from the amnion, adhered to Whartons Jelly and forming the umbilical vessels and allantoid duct. The proposed protocol allowed the collection of a high cellular concentration of umbilical cord progenitor cells from viable cutias.(AU)


A cutia vem sendo utilizada como modelo experimental em diversos estudos voltados à biologia reprodutiva. O cordão umbilical, anexo embrionário que une o feto à placenta, tem sido relatado como um importante sítio anatômico para obtenção de células-tronco. O objetivo deste estudo foi descrever macro e microscopicamente o cordão umbilical de cutias, em fases diferentes da gestação, expandir e cultivar in vitro as células progenitoras e relatar suas características morfológicas. Foram utilizadas sete cutias submetidas à cesariana para a coleta dos cordões umbilicais, cinco foram destinadas aos estudos da estrutura do cordão, em diferentes estágios de gestação (30, 35, 50, 75 e 100 dias pós-coito), e duas, no terço final da gestação, para isolamento e cultivo celular. O cordão umbilical de cutia assume disposição espiralada, com veias e artérias sobre ele a partir dos 50 dias após o coito. As artérias apresentam camada externa de fibras musculares lisas, disposição longitudinal e circular, camada média de fibras musculares lisas, apenas com disposição longitudinal e íntima revestida pelo endotélio. As veias constituídas por fibras musculares lisas longitudinais com um extrato de células musculares lisas e pelo endotélio. Em todas as fases gestacionais analisadas é uma estrutura delimitada por tecido epitelial simples pavimentoso, proveniente do âmnio, aderido a Geleia de Wharton e com formação de vasos umbilicais e ducto alantóide. O protocolo proposto permitiu a coleta de células progenitoras do cordão umbilical de cutias, viáveis com elevada concentração celular.(AU)


Assuntos
Animais , Feminino , Gravidez , Dasyproctidae , Cordão Umbilical/anatomia & histologia , Cordão Umbilical/ultraestrutura , Idade Gestacional , Células Cultivadas , Plasticidade Celular , Separação Celular/veterinária , Cesárea/veterinária
7.
J. venom. anim. toxins incl. trop. dis ; 24: 1-16, 2018. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484750

Resumo

Background Peripheral nerve injury is a worldwide clinical problem, and the preferred surgical method for treating it is the end-to-end neurorrhaphy. When it is not possible due to a large nerve gap, autologous nerve grafting is used. However, these surgical techniques result in nerve regeneration at highly variable degrees. It is thus very important to seek complementary techniques to improve motor and sensory recovery. One promising approach could be cell therapy. Transplantation therapy with human embryonic stem cells (hESCs) is appealing because these cells are pluripotent and can differentiate into specialized cell types and have self-renewal ability. Therefore, the main objective of this study was to find conditions under which functional recovery is improved after sciatic nerve neurorrhaphy. We assumed that hESC, either alone or in combination with heterologous fibrin sealant scaffold, could be used to support regeneration in a mouse model of sciatic nerve injury and repair via autografting with end-to-end neurorrhaphy. Methods Five millimeters of the sciatic nerve of C57BL/6 J mice were transected off and rotated 180 degrees to simulate an injury, and then stumps were sutured. Next, we applied heterologous fibrin sealant and/or human embryonic stem cells genetically altered to overexpress fibroblast growth factor 2 (FGF2) at the site of the injury. The study was designed to include six experimental groups comprising neurorrhaphy (N), neurorrhaphy + heterologous fibrin sealant (N + F), neurorrhaphy + heterologous fibrin sealant + doxycycline (N + F + D), neurorrhaphy + heterologous fibrin sealant + wild-type hESC (N + F + W), neurorrhaphy + heterologous fibrin sealant + hESC off (N + F +T), and neurorrhaphy + heterologous fibrin sealant + hESC on via doxycycline (N + F + D + T). We evaluated the recovery rate using Catwalk and von Frey functional recovery tests, as well as immunohistochemistry analysis. Results The experiments indicated...


Assuntos
Humanos , Adesivo Tecidual de Fibrina , Bioengenharia , Células-Tronco , Nervo Isquiático , Regeneração Nervosa , Traumatismos dos Nervos Periféricos
8.
R. bras. Reprod. Anim. ; 42(3-4): 114-119, jul.-dez. 2018.
Artigo em Francês | VETINDEX | ID: vti-20948

Resumo

Células-tronco são conhecidas pela característica de alto potencial de auto-renovação e podem ser classificadas segundo seu estágio de indiferenciação e perfil epigenético. Células-tronco embrionárias (CTEs) e células-tronco adultas são bastante estudadas e caracterizadas, principalmente nos modelos humano e em camundongos por apresentarem novas possibilidades tanto para a medicina regenerativa quanto para o entendimento do desenvolvimento inicial dos mamíferos. Contudo, a derivação e a manutenção de CTEs em espécies domésticas é desafiadora e apresenta resultados inconsistentes em relação à manutenção da pluripotência in vitro. Nesse contexto, a geração das células pluripotentes induzidas in vitro (células iPS ou iPSCs) é imprescindível para a geração de novas possibilidades na medicina veterinária regenerativa e reprodutiva devido à capacidade de diferenciação destas em uma variedade de outros tipos celulares, inclusive em animais. Assim, esta revisão apresenta a geração das células iPS em animais domésticos, e em especial, recentes estudos sobre as etapas necessárias para a possibilidade de geração de gametas funcionais in vitro, uma importante contribuição na correção de infertilidades, conservação de espécies ameaçadas de extinção e geração de indivíduos geneticamente superiores ou modificados para aplicações agropecuárias ou biomédicas.(AU)


Stem cells are widely known for their high potential for self-renewal, being classified according to their stage of undifferentiation and epigenetic profile. Embryonic stem cells (ES) and adult stem cells are already well studied and characterized, mainly in human and mouse models, once they present new possibilities both for regenerative medicine and for understanding the initial development of mammals. However, the derivation and maintenance of ES in domestic species is challenging and presents inconsistent results regarding maintenance of in vitro pluripotency. In this context, the derivation of in vitro induced pluripotent cells (iPS cells or iPSCs) enables new possibilities in regenerative and reproductive veterinary medicine due to their ability to differentiate into a variety of other cell types. Therefore, this review presents the generation of iPS cells in domestic animals, and focuses on recent studies on the steps necessary for the generation of functional gametes in vitro, an important contribution of stem cells aiming the correction of infertility, the conservation of species in risk of extinction and for the generation of genetically superior or modified organisms for agricultural and biomedical applications.(AU)


Assuntos
Animais , Animais Domésticos/embriologia , Animais Domésticos/genética , Células-Tronco Pluripotentes Induzidas , Técnicas In Vitro , Células Germinativas
9.
Rev. bras. reprod. anim ; 42(3-4): 114-119, jul.-dez. 2018.
Artigo em Francês | VETINDEX | ID: biblio-1492523

Resumo

Células-tronco são conhecidas pela característica de alto potencial de auto-renovação e podem ser classificadas segundo seu estágio de indiferenciação e perfil epigenético. Células-tronco embrionárias (CTEs) e células-tronco adultas são bastante estudadas e caracterizadas, principalmente nos modelos humano e em camundongos por apresentarem novas possibilidades tanto para a medicina regenerativa quanto para o entendimento do desenvolvimento inicial dos mamíferos. Contudo, a derivação e a manutenção de CTEs em espécies domésticas é desafiadora e apresenta resultados inconsistentes em relação à manutenção da pluripotência in vitro. Nesse contexto, a geração das células pluripotentes induzidas in vitro (células iPS ou iPSCs) é imprescindível para a geração de novas possibilidades na medicina veterinária regenerativa e reprodutiva devido à capacidade de diferenciação destas em uma variedade de outros tipos celulares, inclusive em animais. Assim, esta revisão apresenta a geração das células iPS em animais domésticos, e em especial, recentes estudos sobre as etapas necessárias para a possibilidade de geração de gametas funcionais in vitro, uma importante contribuição na correção de infertilidades, conservação de espécies ameaçadas de extinção e geração de indivíduos geneticamente superiores ou modificados para aplicações agropecuárias ou biomédicas.


Stem cells are widely known for their high potential for self-renewal, being classified according to their stage of undifferentiation and epigenetic profile. Embryonic stem cells (ES) and adult stem cells are already well studied and characterized, mainly in human and mouse models, once they present new possibilities both for regenerative medicine and for understanding the initial development of mammals. However, the derivation and maintenance of ES in domestic species is challenging and presents inconsistent results regarding maintenance of in vitro pluripotency. In this context, the derivation of in vitro induced pluripotent cells (iPS cells or iPSCs) enables new possibilities in regenerative and reproductive veterinary medicine due to their ability to differentiate into a variety of other cell types. Therefore, this review presents the generation of iPS cells in domestic animals, and focuses on recent studies on the steps necessary for the generation of functional gametes in vitro, an important contribution of stem cells aiming the correction of infertility, the conservation of species in risk of extinction and for the generation of genetically superior or modified organisms for agricultural and biomedical applications.


Assuntos
Animais , Animais Domésticos/embriologia , Animais Domésticos/genética , Células-Tronco Pluripotentes Induzidas , Técnicas In Vitro , Células Germinativas
10.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 24: 1-16, 2018. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: vti-732655

Resumo

Background Peripheral nerve injury is a worldwide clinical problem, and the preferred surgical method for treating it is the end-to-end neurorrhaphy. When it is not possible due to a large nerve gap, autologous nerve grafting is used. However, these surgical techniques result in nerve regeneration at highly variable degrees. It is thus very important to seek complementary techniques to improve motor and sensory recovery. One promising approach could be cell therapy. Transplantation therapy with human embryonic stem cells (hESCs) is appealing because these cells are pluripotent and can differentiate into specialized cell types and have self-renewal ability. Therefore, the main objective of this study was to find conditions under which functional recovery is improved after sciatic nerve neurorrhaphy. We assumed that hESC, either alone or in combination with heterologous fibrin sealant scaffold, could be used to support regeneration in a mouse model of sciatic nerve injury and repair via autografting with end-to-end neurorrhaphy. Methods Five millimeters of the sciatic nerve of C57BL/6 J mice were transected off and rotated 180 degrees to simulate an injury, and then stumps were sutured. Next, we applied heterologous fibrin sealant and/or human embryonic stem cells genetically altered to overexpress fibroblast growth factor 2 (FGF2) at the site of the injury. The study was designed to include six experimental groups comprising neurorrhaphy (N), neurorrhaphy + heterologous fibrin sealant (N + F), neurorrhaphy + heterologous fibrin sealant + doxycycline (N + F + D), neurorrhaphy + heterologous fibrin sealant + wild-type hESC (N + F + W), neurorrhaphy + heterologous fibrin sealant + hESC off (N + F +T), and neurorrhaphy + heterologous fibrin sealant + hESC on via doxycycline (N + F + D + T). We evaluated the recovery rate using Catwalk and von Frey functional recovery tests, as well as immunohistochemistry analysis. Results The experiments indicated...(AU)


Assuntos
Humanos , Adesivo Tecidual de Fibrina , Fator 2 de Crescimento de Fibroblastos , Nervo Isquiático , Células-Tronco , Bioengenharia , Regeneração Nervosa , Traumatismos dos Nervos Periféricos
11.
Acta cir. bras. ; 32(7): 515-522, July 2017. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-17714

Resumo

Purpose: To evaluate the effects of mesenchymal stem cells on liver regeneration in rats following a 70% hepatectomy. Methods: Forty rats were subjected to 70% hepatectomy and then ~106 mesenchymal stem cells (test group), or saline solution (control group), were infused into their livers via the portal vein. Each treatment group was divided into early and late subgroups (euthanized 3 d and 5 d following the operation, respectively). Group comparisons of Albumin, aminotransaminases (AST, ALT), and Alcaline Phosphatase (AP) levels, proliferative index (ki-67+ straining), and mitotic cell counts were conducted. Results: No significant differences in liver regeneration rate, number of mitoses, proliferative index, or serum levels of albumin, AST, or AP were observed. ALT levels were higher in the test group than in the control group (p .05). Conclusions: Mesenchymal stem-cell therapy did not improve liver regeneration rate 3 d or 5 d after 70% hepatectomy in rats. Likewise, the therapy appeared not to affect liver function, proliferative index, or number of mitoses significantly.(AU)


Assuntos
Animais , Células-Tronco Embrionárias Murinas/transplante , Regeneração Hepática , Hepatectomia
12.
Anim. Reprod. (Online) ; 14(1): 82-88, Jan.-Mar. 2017. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1461256

Resumo

This review aims at putting in perspective the many new developments in our understanding of spermatogonial multiplication and stem cell renewal in non-primate mammals. In the rodent seminiferous epithelium, the spermatogonial compartment can be subdivided into A, In and B spermatogonia, that show no, some or abundant nuclear het erochromatin, respectively. At first, it was thought that all A spermatogonia were spermatogonial stem cells while In and B spermatogonia were in the differentiation pathway. Then there appeared to be a class of so -called undifferentiated A spermatogonia, subdivided according to their topographical arrangement in to singles (As), pairs (Apr) and chains of 4, 8 and 16 A Al spermatogonia. Four (in mouse and rat) subsequent generations of A spermatogonia together with In and B spermatogonia were called differentiating type spermatogonia. A socalled As model was proposed in which the As spermatogonia are the stem cells that self -renew by forming new singles or give rise to Apr spermatogonia that eventually will become spermatozoa. The As model was challenged by the fragmentation model in which stem cell renewal was supposed to occur by way of fragmentation of clones of A al spe rmatogonia.


Assuntos
Células Germinativas/crescimento & desenvolvimento , Células-Tronco Embrionárias Humanas , Espermatogênese
13.
Anim. Reprod. ; 14(1): 82-88, Jan.-Mar. 2017. ilus
Artigo em Inglês | VETINDEX | ID: vti-16117

Resumo

This review aims at putting in perspective the many new developments in our understanding of spermatogonial multiplication and stem cell renewal in non-primate mammals. In the rodent seminiferous epithelium, the spermatogonial compartment can be subdivided into A, In and B spermatogonia, that show no, some or abundant nuclear het erochromatin, respectively. At first, it was thought that all A spermatogonia were spermatogonial stem cells while In and B spermatogonia were in the differentiation pathway. Then there appeared to be a class of so -called undifferentiated A spermatogonia, subdivided according to their topographical arrangement in to singles (As), pairs (Apr) and chains of 4, 8 and 16 A Al spermatogonia. Four (in mouse and rat) subsequent generations of A spermatogonia together with In and B spermatogonia were called differentiating type spermatogonia. A socalled As model was proposed in which the As spermatogonia are the stem cells that self -renew by forming new singles or give rise to Apr spermatogonia that eventually will become spermatozoa. The As model was challenged by the fragmentation model in which stem cell renewal was supposed to occur by way of fragmentation of clones of A al spe rmatogonia.(AU)


Assuntos
Células-Tronco Embrionárias Humanas , Células Germinativas/crescimento & desenvolvimento , Espermatogênese
14.
Vet. Zoot. ; 24(3 Supl.1): 118-126, Sept. 2017.
Artigo em Inglês | VETINDEX | ID: vti-17341

Resumo

Buffaloes are dairy, meat and work farm animals very adapted to tropical regions, with large productivity and economic potential in several countries, including Brazil. In some states, the lack of technology in buffalo farming has increased reproductive and sanitary problems, turning imminent the extinction of these animals. In this contest, studies related to stem cell biotechnology have resulted in other possible utilization of buffaloes as experimental model, allowing the expansion of knowledge in this specie in particular cell characteristics. Stem cells have been the subject of many studies in several species, nevertheless buffaloes studies are scarce. Thus, this review aims to assemble and connect buffaloes and stem cells biotechnology studies to demonstrate the importance of research to increase the advancement of these two fields.(AU)


A Bubalinocultura abrange animais de tripla aptidão muito adaptados aos climas tropicais e com grande potencial produtivo e econômico em vários países, inclusive no Brasil. Em algumas regiões, a falta de tecnificação na produção de bubalinos tem agravado problemas reprodutivos e sanitários, tornando iminente a extinção desses animais. Nesse contexto, estudos relacionados à biotecnologia de células-tronco têm indicado resultados que viabilizam a utilização de búfalos como modelo experimental, além de permitir a ampliação dos conhecimentos acerca da espécie e de seu comportamento celular característico. As células-tronco têm sido alvo de muitas pesquisas em várias espécies, porém os estudos com bubalinos ainda são escassos. Desta forma, o objetivo dessa revisão foi reunir estudos relacionados à bubalinocultura e biotecnologia de células-tronco e demonstrar a importância das pesquisas que contribuem para o avanço dessas duas áreas.(AU)


La Bubalinocultura abarca animales de triple aptitud muy adaptados a los climas tropicales y con gran potencial productivo y económico en varios países, incluso en Brasil. En algunas regiones, la falta de tecnificación en la producción de bufalinos ha agravado problemas reproductivos y sanitarios, haciendo inminente la extinción de estos animales. En ese contexto, Estudios relacionados con la biotecnología de células madre han indicado resultados que viabilizan la utilización de búfalos como modelo experimental, además de permitir la ampliación de los conocimientos sobre la especie y su comportamiento celular característico. Las células madre han sido objeto de muchas investigaciones en várias espécies, pero los estudios con bubalinos todavía son escasos. De esta forma, el objetivo de esta revisión fue reunir estudios relacionados con la bubalinocultura y biotecnología de células madre y demostrar la importancia de las investigaciones que contribuyen al avance de estas dos áreas.(AU)


Assuntos
Animais , Búfalos , Biotecnologia/métodos , Células-Tronco , Pesquisa com Células-Tronco , Terapia Baseada em Transplante de Células e Tecidos/veterinária
15.
Vet. zootec ; 24(3 Supl.1): 118-126, Sept. 2017.
Artigo em Inglês | VETINDEX | ID: biblio-1503463

Resumo

Buffaloes are dairy, meat and work farm animals very adapted to tropical regions, with large productivity and economic potential in several countries, including Brazil. In some states, the lack of technology in buffalo farming has increased reproductive and sanitary problems, turning imminent the extinction of these animals. In this contest, studies related to stem cell biotechnology have resulted in other possible utilization of buffaloes as experimental model, allowing the expansion of knowledge in this specie in particular cell characteristics. Stem cells have been the subject of many studies in several species, nevertheless buffaloes studies are scarce. Thus, this review aims to assemble and connect buffaloes and stem cells biotechnology studies to demonstrate the importance of research to increase the advancement of these two fields.


A Bubalinocultura abrange animais de tripla aptidão muito adaptados aos climas tropicais e com grande potencial produtivo e econômico em vários países, inclusive no Brasil. Em algumas regiões, a falta de tecnificação na produção de bubalinos tem agravado problemas reprodutivos e sanitários, tornando iminente a extinção desses animais. Nesse contexto, estudos relacionados à biotecnologia de células-tronco têm indicado resultados que viabilizam a utilização de búfalos como modelo experimental, além de permitir a ampliação dos conhecimentos acerca da espécie e de seu comportamento celular característico. As células-tronco têm sido alvo de muitas pesquisas em várias espécies, porém os estudos com bubalinos ainda são escassos. Desta forma, o objetivo dessa revisão foi reunir estudos relacionados à bubalinocultura e biotecnologia de células-tronco e demonstrar a importância das pesquisas que contribuem para o avanço dessas duas áreas.


La Bubalinocultura abarca animales de triple aptitud muy adaptados a los climas tropicales y con gran potencial productivo y económico en varios países, incluso en Brasil. En algunas regiones, la falta de tecnificación en la producción de bufalinos ha agravado problemas reproductivos y sanitarios, haciendo inminente la extinción de estos animales. En ese contexto, Estudios relacionados con la biotecnología de células madre han indicado resultados que viabilizan la utilización de búfalos como modelo experimental, además de permitir la ampliación de los conocimientos sobre la especie y su comportamiento celular característico. Las células madre han sido objeto de muchas investigaciones en várias espécies, pero los estudios con bubalinos todavía son escasos. De esta forma, el objetivo de esta revisión fue reunir estudios relacionados con la bubalinocultura y biotecnología de células madre y demostrar la importancia de las investigaciones que contribuyen al avance de estas dos áreas.


Assuntos
Animais , Biotecnologia/métodos , Búfalos , Células-Tronco , Pesquisa com Células-Tronco , Terapia Baseada em Transplante de Células e Tecidos/veterinária
16.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 54(2): 168-177, 2017. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-875125

Resumo

The interest in embryology, the science of the development of a zygote into a completely developed foetus, has increased greatly in recent years due to a number of studies involving embryonic and induced pluripotent stem cells. In addition, the development of techniques such as cloning has aided to understand the critical events that occur during embryonic development. In this study, we describe the morphology of two sheep embryos and one foetus using macroscopic and microscopic techniques. We investigated sheep without defined breed on days 24, 32, and 50 of gestation (estimated by crown-rump length [CR]). Macroscopically, we observed the development of E1 (24 days), with visible optic vesicle, but without retinal pigmentation and the forelimbs bud in development. In the E2 (32 days), we noticed the presence of optic retinal pigmentation and forelimbs more developed in comparison with E1. As expected, F1 revealed an eyeball already covered and the forelimbs developed. Meanwhile, microscopic analysis revealed somite, ventricle, atrium, and oral cavity in development in E1. However, in F1 we were able to identify more complex structures, such as ossification in the spine, ventricle, atrium, intraventricular septum, pericardial sac, and oral cavity with tongue. This work brings more precise and detailed data on the morphological characteristics of the major organ systems (nervous, circulatory, respiratory, digestive, and urinary) at each embryonic and foetal stage analysed.(AU)


O interesse em Embriologia, a ciência do desenvolvimento de um zigoto em um feto completamente desenvolvido, tem aumentado consideravelmente nos últimos anos devido a uma série de estudos envolvendo células-tronco pluripotentes embrionárias e induzidas. Além disso, o desenvolvimento de técnicas como a clonagem tem ajudado a compreender os eventos críticos que ocorrem durante o desenvolvimento embrionário. Neste estudo, descrevemos a morfologia de dois embriões de ovinos e um feto utilizando técnicas macroscópicas e microscópicas. Obtivemos ovelhas sem raça definida com 24, 32 e 50 dias de gestação (estimado pelo método de Crown-Rump, CR). Os conceptos foram mensurados, pesados e caracterizados a olho nu. Macroscopicamente, observamos o desenvolvimento dos embriões E1 (24 dias), apresentando globo ocular sem pigmentação de retina e broto do membro torácico e pélvico. Já o E2 (32 dias), apresentava globo ocular com pigmentação na retina e os membros torácicos e pélvicos mais desenvolvidos. O F1 apresentou olhos cobertos com uma membrana e membros torácicos e pélvicos mais desenvolvidos. Enquanto isso, microscopicamente observamos no E1 somitos, ventrículo, átrio e cavidade oral ainda em desenvolvimento. Porém, no F1 já era possível observar ossificação da coluna espinhal, coração com estruturas mais complexas, como ventrículo, átrio, septo interventricular e saco pericárdio. Além disso, na cavidade oral observamos a formação da língua. Este trabalho fornece informações precisas e detalhadas sobre as características morfológicas dos principais órgãos dos sistemas (nervoso, circulatório, respiratório, digestivo e urinário) em cada fase embrionária e fetal analisadas.(AU)


Assuntos
Animais , Embrião de Mamíferos/anatomia & histologia , Desenvolvimento Embrionário , Desenvolvimento Fetal , Feto/anatomia & histologia , Ovinos/embriologia
17.
Braz. j. vet. res. anim. sci ; 54(2): 168-177, 2017. ilus
Artigo em Inglês | VETINDEX | ID: vti-15689

Resumo

The interest in embryology, the science of the development of a zygote into a completely developed foetus, has increased greatly in recent years due to a number of studies involving embryonic and induced pluripotent stem cells. In addition, the development of techniques such as cloning has aided to understand the critical events that occur during embryonic development. In this study, we describe the morphology of two sheep embryos and one foetus using macroscopic and microscopic techniques. We investigated sheep without defined breed on days 24, 32, and 50 of gestation (estimated by crown-rump length [CR]). Macroscopically, we observed the development of E1 (24 days), with visible optic vesicle, but without retinal pigmentation and the forelimbs bud in development. In the E2 (32 days), we noticed the presence of optic retinal pigmentation and forelimbs more developed in comparison with E1. As expected, F1 revealed an eyeball already covered and the forelimbs developed. Meanwhile, microscopic analysis revealed somite, ventricle, atrium, and oral cavity in development in E1. However, in F1 we were able to identify more complex structures, such as ossification in the spine, ventricle, atrium, intraventricular septum, pericardial sac, and oral cavity with tongue. This work brings more precise and detailed data on the morphological characteristics of the major organ systems (nervous, circulatory, respiratory, digestive, and urinary) at each embryonic and foetal stage analysed.(AU)


O interesse em Embriologia, a ciência do desenvolvimento de um zigoto em um feto completamente desenvolvido, tem aumentado consideravelmente nos últimos anos devido a uma série de estudos envolvendo células-tronco pluripotentes embrionárias e induzidas. Além disso, o desenvolvimento de técnicas como a clonagem tem ajudado a compreender os eventos críticos que ocorrem durante o desenvolvimento embrionário. Neste estudo, descrevemos a morfologia de dois embriões de ovinos e um feto utilizando técnicas macroscópicas e microscópicas. Obtivemos ovelhas sem raça definida com 24, 32 e 50 dias de gestação (estimado pelo método de Crown-Rump, CR). Os conceptos foram mensurados, pesados e caracterizados a olho nu. Macroscopicamente, observamos o desenvolvimento dos embriões E1 (24 dias), apresentando globo ocular sem pigmentação de retina e broto do membro torácico e pélvico. Já o E2 (32 dias), apresentava globo ocular com pigmentação na retina e os membros torácicos e pélvicos mais desenvolvidos. O F1 apresentou olhos cobertos com uma membrana e membros torácicos e pélvicos mais desenvolvidos. Enquanto isso, microscopicamente observamos no E1 somitos, ventrículo, átrio e cavidade oral ainda em desenvolvimento. Porém, no F1 já era possível observar ossificação da coluna espinhal, coração com estruturas mais complexas, como ventrículo, átrio, septo interventricular e saco pericárdio. Além disso, na cavidade oral observamos a formação da língua. Este trabalho fornece informações precisas e detalhadas sobre as características morfológicas dos principais órgãos dos sistemas (nervoso, circulatório, respiratório, digestivo e urinário) em cada fase embrionária e fetal analisadas.(AU)


Assuntos
Animais , Ovinos/embriologia , Desenvolvimento Embrionário , Embrião de Mamíferos/anatomia & histologia , Desenvolvimento Fetal , Feto/anatomia & histologia
18.
Anim. Reprod. (Online) ; 14(4): 1110-1123, Oct.-Dec. 2017. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1461307

Resumo

The birth of cloned goats has been well documented, but the overall goat cloning efficiency by somatic cell nuclear transfer procedures is still low, which may be further intensified in extreme environments. The aim of this study was to produce cloned goats under the conditions of the Brazilian Semi Arid region, in a transgenic program for the expression of human lysozyme in the milk to target childhood diarrhea and malnutrition, comparing the effects of oocyte source, cell type, and embryo reconstruction procedures on in vitro and in vivo embryo survival after cloning by micromanipulation or by handmade cloning. The use of in vitro-matured oocytes resulted in more viable embryos after cloning than in vivo-matured cytoplasts, but no differences in pregnancy rates on day 23 were seen between oocyte sources (77.5 vs. 77.8%, respectively). The presence or absence of the zona pellucida for embryo reconstruction (78.8 vs. 76.0%, respectively) did not affect pregnancy outcome after transfer. However, pregnancy rate on day 23 was higher for embryos chemically activated by a conventional than a modified protocol (88.1 vs. 50.0%), and for embryos reconstructed with mesenchymal stem cells and fetal fibroblasts (100.0 and 93.3%) than with adult fibroblasts (64.7%). Although most pregnancies were lost, the birth of a cloned female was obtained from embryos reconstructed by micromanipulation using non-transgenic control cells and in vitro-matured oocytes with intact zona pellucida, after conventional activation and transfer at the 1-cell stage.


Assuntos
Animais , Cabras/embriologia , Clonagem de Organismos , Clonagem de Organismos/tendências , Técnicas de Maturação in Vitro de Oócitos/veterinária
19.
Anim. Reprod. ; 14(4): 1110-1123, Oct.-Dec. 2017. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-18090

Resumo

The birth of cloned goats has been well documented, but the overall goat cloning efficiency by somatic cell nuclear transfer procedures is still low, which may be further intensified in extreme environments. The aim of this study was to produce cloned goats under the conditions of the Brazilian Semi Arid region, in a transgenic program for the expression of human lysozyme in the milk to target childhood diarrhea and malnutrition, comparing the effects of oocyte source, cell type, and embryo reconstruction procedures on in vitro and in vivo embryo survival after cloning by micromanipulation or by handmade cloning. The use of in vitro-matured oocytes resulted in more viable embryos after cloning than in vivo-matured cytoplasts, but no differences in pregnancy rates on day 23 were seen between oocyte sources (77.5 vs. 77.8%, respectively). The presence or absence of the zona pellucida for embryo reconstruction (78.8 vs. 76.0%, respectively) did not affect pregnancy outcome after transfer. However, pregnancy rate on day 23 was higher for embryos chemically activated by a conventional than a modified protocol (88.1 vs. 50.0%), and for embryos reconstructed with mesenchymal stem cells and fetal fibroblasts (100.0 and 93.3%) than with adult fibroblasts (64.7%). Although most pregnancies were lost, the birth of a cloned female was obtained from embryos reconstructed by micromanipulation using non-transgenic control cells and in vitro-matured oocytes with intact zona pellucida, after conventional activation and transfer at the 1-cell stage.(AU)


Assuntos
Animais , Cabras/embriologia , Técnicas de Maturação in Vitro de Oócitos/veterinária , Clonagem de Organismos/tendências , Clonagem de Organismos
20.
Anim. Reprod. (Online) ; 14(1): 61-68, Jan.-Mar. 2017. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1461254

Resumo

All the somatic cells composing a mammalian organism are genetically identical and contain the same DNA sequence. Nevertheless, they are able to adopt a distinct commitment, differentiate in a tissue specific way and respond to developmental cues, acquiring a terminal phenotype. At the end of the differentiation process, each cell is highly specialized and committed to a distinct determined fate. This is possible thanks to tissue-specific gene expression, timely regulated by epigenetic modifications, that gradually limit cell potency to a more restricted phenotype-related expression pattern. Complex chemical modifications of DNA, RNA and associated proteins, that determine activation or silencing of certain genes are responsible for the ‘epigenetic control’ that triggers the restriction of cell pluripotency, with the acquisition of the phenotypic definition and the preservation of its stability during subsequent cell divisions. The process is however reversible and may be modified by biochemical and biological manipulation, leading to the reactivation of hypermethylated pluripotency genes and inducing cells to transit from a terminally committed state to a higher plasticity one.These epigenetic regulatory mechanisms play a key role in embryonic development since they drive phenotype definition and tissue differentiation. At the same time, they are crucial for a better understanding of pluripotency regulation and restriction, stem cell biology and tissue repair process.


Assuntos
Epigênese Genética/fisiologia , Epigênese Genética/genética , Plasticidade Celular , Células Híbridas , Sequência de Bases
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