Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 347
Filter
1.
Int. j. morphol ; 42(1): 21-27, feb. 2024. ilus
Article in Spanish | LILACS | ID: biblio-1528821

ABSTRACT

El cobayo es un modelo animal ampliamente utilizado en la investigación biomédica debido a sus similitudes biológicas con los seres humanos. El objetivo de nuestro estudio es proporcionar sustento morfológico para utilizar preparados histológicos de embriones de cobayo como modelo de estudio para comprender los procesos del desarrollo embrionario humano. Nuestros resultados muestran que los embriones de cobayo presentan características morfológicas similares a las observadas en los embriones humanos, lo que sugiere que pueden utilizarse como un modelo efectivo para estudiar el desarrollo embrionario humano. Este hallazgo tiene importantes implicancias para la investigación y la docencia utilizando este modelo animal. Se analizaron preparados histológicos de embriones de cobayo teñidos con hematoxilina eosina, adquiridos por la Universidad Autónoma de Chile. Se tomaron microfotografías de preparados histológicos de cobayo en diferentes estadios del desarrollo y se seleccionaron las mejores imágenes para la descripción de estructuras y establecer estimados de la embriogénesis. Del análisis de los preparados se desprende que órganos como esófago, médula espinal y corazón presentan similitudes anatómicas e histológicas que hacen posible compararlas con el desarrollo embrionario humano y la edad de gestación en etapas tempranas. El uso de preparados de embriones de cobayo y su análisis desde un aspecto histológico resulta ser una estrategia metodológica factible debido a las similitudes en la embriogénesis de los mamíferos y las concordancias morfológicas con el desarrollo de los órganos entre humanos y roedores. Esto permite implementar este modelo animal como una herramienta para comprender el desarrollo embrionario humano.


SUMMARY: The guinea pig is an animal model widely used in biomedical research due to its biological similarities with humans. The objective of our study is to provide morphological support to use histological preparations of guinea pig embryos as a study model to understand the processes of human embryonic development. Our results show that guinea pig embryos present morphological characteristics similar to those observed in human embryos, suggesting that they can be used as an effective model to study human embryonic development. This finding has important implications for research and teaching using this animal model. Histological preparations of guinea pig embryos stained with hematoxylin eosin, acquired by the Autonomous University of Chile, were analyzed. Photomicrographs of histological preparations of guinea pigs at different stages of development were taken and the best images were selected to describe structures and establish estimates of embryogenesis. From the analysis of the preparations it is clear that organs such as the esophagus, spinal cord and heart present anatomical and histological similarities that make it possible to compare them with human embryonic development and gestation age in early stages. The use of guinea pig embryo preparations and their analysis from a histological aspect turns out to be a feasible methodological strategy due to the similarities in mammalian embryogenesis and the morphological concordances with the development of organs between humans and rodents. This allows this animal model to be implemented as a tool to understand human embryonic development.


Subject(s)
Humans , Animals , Guinea Pigs , Embryonic Development , Embryo, Mammalian/anatomy & histology
2.
Estud. Psicol. (Campinas, Online) ; 40: e210091, 2023. graf
Article in English | LILACS, INDEXPSI | ID: biblio-1448240

ABSTRACT

Objective: This study analyzed the relation between the position of scientists on embryo editing and the different types of knowledge involved. Methods: A lexical analysis of 151 scientific articles in the PubMed and Web of Science databases was conducted using the IRAMUTEQ software. Results: The results showed that gene editing in embryos is presented in two argumentative branches: the first refers to the editing technique and its possibilities; the second discusses the impacts of these techniques on the public arena. The results demonstrate a consensus regarding the potential of editing; however, dilemmas about its effectiveness were also highlighted. Conclusion: The presence of ethical conflicts with embryo editing among the specialists was evidenced especially regarding the birth of genetically modified babies. Therefore, gene editing is marked by conflicts that are not limited only to biological contexts, but that encompasses different aspects of social life.


Objetivo: O objetivo deste trabalho foi analisar a relação entre o posicionamento dos cientistas sobre a edição de embriões e os diferentes tipos de conhecimento envolvidos nesses debates. Método: Utilizando o software IRAMUTEQ realizou-se uma análise lexical de 151 artigos científicos nas bases de dados PubMed e Web of Science. Resultados: Os resultados demonstraram que a edição genética de embriões se apresenta em dois blocos argumentativos: o primeiro se refere à técnica de edição e suas possibilidades e o segundo discute os impactos dessas técnicas na arena pública. Os achados demonstram consenso sobre as potencialidades da edição, contudo dilemas sobre a sua eficácia foram também destacados. Conclusão: Evidenciou-se a presença de embates éticos sobre a edição de embriões entre os especialistas em relação ao nascimento de bebês geneticamente modificados. Observou-se que a edição genética é marcada por conflitos que não se limitam apenas a contextos biológicos, mas que tangem diferentes aspectos da vida social.


Subject(s)
Bioethics , Embryo, Mammalian , Gene Editing , Social Representation
3.
Protein & Cell ; (12): 337-349, 2023.
Article in English | WPRIM | ID: wpr-982551

ABSTRACT

Human pluripotent stem cells provide an inexhaustible model to study human embryogenesis in vitro. Recent studies have provided diverse models to generate human blastoids by self-organization of different pluripotent stem cells or somatic reprogramming intermediates. However, whether blastoids can be generated from other cell types or whether they can recapitulate postimplantation development in vitro is unknown. Here, we develop a strategy to generate human blastoids from heterogeneous intermediates with epiblast, trophectoderm, and primitive endoderm signatures of the primed-to-naïve conversion process, which resemble natural blastocysts in morphological architecture, composition of cell lineages, transcriptome, and lineage differentiation potential. In addition, these blastoids reflect many features of human peri-implantation and pregastrulation development when further cultured in an in vitro 3D culture system. In summary, our study provides an alternative strategy to generate human blastoids and offers insights into human early embryogenesis by modeling peri- and postimplantation development in vitro.


Subject(s)
Humans , Pluripotent Stem Cells/metabolism , Embryo, Mammalian/metabolism , Cell Differentiation , Blastocyst , Cell Lineage , Embryonic Development
4.
Protein & Cell ; (12): 262-278, 2023.
Article in English | WPRIM | ID: wpr-982545

ABSTRACT

Self-organized blastoids from extended pluripotent stem (EPS) cells possess enormous potential for investigating postimplantation embryo development and related diseases. However, the limited ability of postimplantation development of EPS-blastoids hinders its further application. In this study, single-cell transcriptomic analysis indicated that the "trophectoderm (TE)-like structure" of EPS-blastoids was primarily composed of primitive endoderm (PrE)-related cells instead of TE-related cells. We further identified PrE-like cells in EPS cell culture that contribute to the blastoid formation with TE-like structure. Inhibition of PrE cell differentiation by inhibiting MEK signaling or knockout of Gata6 in EPS cells markedly suppressed EPS-blastoid formation. Furthermore, we demonstrated that blastocyst-like structures reconstituted by combining the EPS-derived bilineage embryo-like structure (BLES) with either tetraploid embryos or tetraploid TE cells could implant normally and develop into live fetuses. In summary, our study reveals that TE improvement is critical for constructing a functional embryo using stem cells in vitro.


Subject(s)
Pregnancy , Female , Animals , Mice , Tetraploidy , Blastocyst , Embryo, Mammalian , Cell Differentiation , Embryonic Development
5.
Acta bioeth ; 28(2): 239-247, oct. 2022. ilus
Article in Spanish | LILACS | ID: biblio-1402930

ABSTRACT

Resumen: Objetivo. Analizar las percepciones y prácticas de los clínicos en relación con el manejo del embrión sometido a técnicas de fecundación in vitro. Metodología. Cualitativa (subjetivista y fenomenológico). Se realizaron 15 las entrevistas semiestructuradas aplicando un muestreo por saturación dirigidas a personal clínico que haya participado en procedimientos de fecundación in vitro. Los datos se analizaron con el programa Atlas Ti 8.0®. Resultado. Los clínicos consideran al embrión como un ser humano o futuro ser humano y, además, merecedor de respeto y consideración, proponiendo incluso mejoras en los procesos de manipulación y almacenaje. Conclusión. Los embriones no son considerados como entes susceptibles de recibir daño, desde argumentos no solo técnicos sino éticos. Desde la corriente principialista, se describe la necesidad de promover actitudes de responsabilidad y prudencia para evitar el dogmatismo (objetivismo moral) proponiendo una postura deliberativa.


Abstract: The objective of this paper is to analyze the perceptions and practices of clinicians in relation to the management of embryos subjected to in vitro fertilization techniques. Methodology is Qualitative (subjectivist and phenomenological). A total of 15 semi-structured interviews were conducted using saturation sampling for clinical personnel who have participated in vitro fertilization procedures. The data is analyzed with the Atlas Ti 8.0® program. Results: Clinicians consider the embryo as a Human being or future human being, in addition, deserving of respect and consideration even proposing improvements in the processes of handling and storage. Conclusion. Embryos are not considered as entities susceptible of damage from not only technical but ethical arguments. From the principialist current, the need to promote attitudes of responsibility and prudence to avoid dogmatism (moral objectivism) is described, proposing a deliberative position.


Resumo: Objetivo. Analisar as percepções e práticas dos médicos em relação ao manejo do embrião submetido a técnicas de fertilização in vitro. Metodologia. Qualitativo (subjetivo e fenomenológico). Foram realizadas 15 entrevistas semiestruturadas por amostragem de saturação para pessoal clínico que participou de procedimentos de fertilização in vitro. Os dados são analisados com o programa Atlas Ti 8.0®. Resultado. Os médicos consideram o embrião como um ser humano ou futuro, além de merecer respeito e consideração, propondo até melhorias nos processos de manuseio e armazenamento. Conclusão. Os embriões não são considerados como entidades suscetíveis a receber danos não apenas de argumentos técnicos, mas éticos. A partir da corrente principialista, descreve-se a necessidade de promover atitudes de responsabilidade e prudência para evitar o dogmatismo (objetivismo moral), propondo uma posição deliberativa.


Subject(s)
Humans , Fertilization in Vitro/ethics , Health Personnel/psychology , Embryo, Mammalian , Embryo Transfer/ethics , Perception , Interviews as Topic , Qualitative Research , Respect
7.
Protein & Cell ; (12): 316-335, 2022.
Article in English | WPRIM | ID: wpr-929165

ABSTRACT

Recent advances in genome editing, especially CRISPR-Cas nucleases, have revolutionized both laboratory research and clinical therapeutics. CRISPR-Cas nucleases, together with the DNA damage repair pathway in cells, enable both genetic diversification by classical non-homologous end joining (c-NHEJ) and precise genome modification by homology-based repair (HBR). Genome editing in zygotes is a convenient way to edit the germline, paving the way for animal disease model generation, as well as human embryo genome editing therapy for some life-threatening and incurable diseases. HBR efficiency is highly dependent on the DNA donor that is utilized as a repair template. Here, we review recent progress in improving CRISPR-Cas nuclease-induced HBR in mammalian embryos by designing a suitable DNA donor. Moreover, we want to provide a guide for producing animal disease models and correcting genetic mutations through CRISPR-Cas nuclease-induced HBR in mammalian embryos. Finally, we discuss recent developments in precise genome-modification technology based on the CRISPR-Cas system.


Subject(s)
Animals , CRISPR-Cas Systems/genetics , DNA/genetics , Embryo, Mammalian/metabolism , Endonucleases/metabolism , Gene Editing , Mammals/metabolism
8.
Protein & Cell ; (12): 490-512, 2022.
Article in English | WPRIM | ID: wpr-939864

ABSTRACT

LIN28 is an RNA binding protein with important roles in early embryo development, stem cell differentiation/reprogramming, tumorigenesis and metabolism. Previous studies have focused mainly on its role in the cytosol where it interacts with Let-7 microRNA precursors or mRNAs, and few have addressed LIN28's role within the nucleus. Here, we show that LIN28 displays dynamic temporal and spatial expression during murine embryo development. Maternal LIN28 expression drops upon exit from the 2-cell stage, and zygotic LIN28 protein is induced at the forming nucleolus during 4-cell to blastocyst stage development, to become dominantly expressed in the cytosol after implantation. In cultured pluripotent stem cells (PSCs), loss of LIN28 led to nucleolar stress and activation of a 2-cell/4-cell-like transcriptional program characterized by the expression of endogenous retrovirus genes. Mechanistically, LIN28 binds to small nucleolar RNAs and rRNA to maintain nucleolar integrity, and its loss leads to nucleolar phase separation defects, ribosomal stress and activation of P53 which in turn binds to and activates 2C transcription factor Dux. LIN28 also resides in a complex containing the nucleolar factor Nucleolin (NCL) and the transcriptional repressor TRIM28, and LIN28 loss leads to reduced occupancy of the NCL/TRIM28 complex on the Dux and rDNA loci, and thus de-repressed Dux and reduced rRNA expression. Lin28 knockout cells with nucleolar stress are more likely to assume a slowly cycling, translationally inert and anabolically inactive state, which is a part of previously unappreciated 2C-like transcriptional program. These findings elucidate novel roles for nucleolar LIN28 in PSCs, and a new mechanism linking 2C program and nucleolar functions in PSCs and early embryo development.


Subject(s)
Animals , Mice , Cell Differentiation , Embryo, Mammalian/metabolism , Embryonic Development , Pluripotent Stem Cells/metabolism , RNA, Messenger/genetics , RNA, Ribosomal , RNA-Binding Proteins/metabolism , Transcription Factors/metabolism , Zygote/metabolism
9.
In. Kimelman Flechner, Dana; Taranto González, Fernando Carlos. Oncofertilidad: aspectos prácticos y abordaje interdisciplinario. Montevideo, Oficina del Libro FEFMUR, c2022. p.167-173.
Monography in Spanish | LILACS, UY-BNMED, BNUY | ID: biblio-1413662
10.
Arq. bras. med. vet. zootec. (Online) ; 73(4): 799-811, Jul.-Aug. 2021. tab, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1285263

ABSTRACT

This study aimed to evaluate the ultrastructural morphometry of bovine embryos produced in vitro grown at different concentrations of antioxidants. After in vitro maturation and fertilization, the presumptive zygotes were assigned into five treatments. T1) without the addition of any antioxidants (negative control); T2) addition of 50µM/mL cysteamine; and T3, T4 and T5) adding 2.5µg/mL, 5.0µg/mL or 10.0µg/mL of the antioxidants derived from the oily extract from Lippia origanoides, respectively. On D7 of culture, the embryos in the blastocyst stage were fixed and prepared for electron transmission microscopy. These were evaluated for the proportion of cytoplasm-to-nucleus, cytoplasm-to-mitochondria, cytoplasm-to-vacuoles, cytoplasm-to-autophagic vacuoles and cytoplasm-to-lipid droplets. Blastocysts cultured in media containing oily extract of Lippia origanoides presented morphological characteristics such as high cell:mitochondria ratio and low cell:vacuoles and cell:autophagic vacuole ratio, possibly been morphological indicators of embryonic quality. Inner cell mass (ICM) from blastocysts cultured in media without any antioxidants had the highest cell:vacuole ratio. Similar results were found in the trophectoderm (TE) cells of blastocysts from treatment 2. Embryo culture media supplemented with antioxidants derived from Lippia origanoides oil produced embryos with a higher cytoplasmic proportion of organelles, such as mitochondria. Also, treatments without any antioxidants or with the addition of cysteamine presented cytoplasmic vacuolization, a characteristic related to production of poor-quality embryos.(AU)


Este estudo teve como objetivo avaliar a morfometria ultraestrutural de embriões bovinos produzidos in vitro e cultivados em diferentes concentrações de antioxidantes. Após a maturação e a fertilização in vitro, os possíveis zigotos foram divididos em cinco tratamentos: T1) sem adição de antioxidantes (controle negativo); T2) adição de 50µM/mL de cisteamina; e T3, T4 e T5) adição de 2,5µg/mL, 5,0µg/mL ou 10,0µg/mL dos antioxidantes derivados do extrato oleoso de Lippia origanoides, respectivamente. No D7 de cultivo, os embriões em estágio de blastocisto foram fixados e preparados para microscopia eletrônica de transmissão. Estes foram avaliados para a proporção entre citoplasma e núcleo, citoplasma e mitocôndria, citoplasma e vacúolos, citoplasma e vacúolos autofágicos e citoplasma e gotículas lipídicas. Blastocistos cultivados em meio contendo extrato oleoso de Lippia origanoides apresentaram características morfológicas como alta relação célula:mitocôndria e baixa relação célula:vacúolos e célula:vacúolo autofágico, possíveis indicadores morfológicos de qualidade embrionária. A massa celular interna (MCI) de blastocistos cultivados em meio sem quaisquer antioxidantes teve a maior razão célula:vacúolo. Resultados semelhantes foram encontrados nas células do trofectoderma (TE) de blastocistos do tratamento 2. Portanto, o meio de cultivo embrionário suplementado com antioxidantes derivados do óleo de Lippia origanoides produziu embriões com maior proporção citoplasmática de organelas, como mitocôndrias. Além disso, tratamentos sem antioxidantes ou com adição de cisteamina apresentaram vacuolização citoplasmática, característica relacionada à produção de embriões de baixa qualidade.(AU)


Subject(s)
Blastocyst , Cysteamine , Lippia , Embryo, Mammalian/ultrastructure , In Vitro Techniques/veterinary , Antioxidants
11.
Arq. bras. med. vet. zootec. (Online) ; 73(1): 256-260, Jan.-Feb. 2021. tab, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1153048

ABSTRACT

As vantagens dos animais transgênicos têm sido demonstradas em diferentes aplicações, entretanto muitas metodologias usadas para gerar animais geneticamente modificados (GM) apresentam baixas taxas de eficiência. O objetivo deste estudo foi avaliar a entrega dos vetores lentivirais (VLs) em zigotos durante a fertilização in vitro (FIV), para gerar embriões GM, com o gene da proteína verde fluorescente (GFP) ou do fator IX de coagulação humana (FIX). Vetores lentivirais com os genes GFP (pLGW-GFP-LV) ou FIX (pLWE2-FIX-LV) foram utilizados na FIV ou na cultura de embriões in vitro (CIV). A coincubação de pLWE2-FIX-LV com espermatozoides e complexos oócitos-células do cumulus (COCs) durante a FIV diminuiu (P<0,05) as taxas de clivagem e de blastocistos, enquanto com pLGW-GFP-LV diminuiu (P<0,05) a taxa de blastocisto quando se comparou ao controle sem VL. A coincubação de pLWE2-FIX-LV e pLGW-GFP-LV com presumíveis zigotos durante a CIV não afetou (P>0,05) o desenvolvimento embrionário. A expressão da proteína GFP não foi detectada em embriões após a coincubação de FIV ou CIV, embora as células do cumulus expressassem a proteína até o dia oito de cultivo in vitro. Reações em cadeia da polimerase (PCR) não detectaram os genes GFP ou FIX em embriões, mas ambos foram detectados em células do cumulus. Assim, a coincubação de VL com espermatozoide bovino e COCs não é eficaz para produzir embriões geneticamente modificados por meio de FIV.(AU)


Subject(s)
Animals , Cattle , Zygote , Animals, Genetically Modified/genetics , Transgenes , Embryo, Mammalian , Genetic Vectors/analysis , Fertilization in Vitro/veterinary , Gene Transfer Techniques/veterinary
12.
Rev. bras. ginecol. obstet ; 43(1): 28-34, Jan. 2021. tab, graf
Article in English | LILACS | ID: biblio-1156078

ABSTRACT

Abstract Objective To determine embryo quality (mean graduated embryo score [GES]) in infertile patients with endometriosis undergoing in vitro fertilization with embryo transfer (IVF-ET) compared with infertile patients without endometriosis. Methods A case-control study was performed comparing 706 embryos (162 patients) divided into 2 groups: 472 embryos derived from patients without endometriosis (n= 109, infertile patients with tubal infertility) and 234 embryos from patients in the study group (n= 53, infertile patients with peritoneal endometriosis). All patients were subjected to IVF using an oestradiol-antagonist-recombinant follicle-stimulating hormone (FSH) protocol for ovarian stimulation. Themean GESwas performed to evaluate all embryos at 3 points in time: 16 to 18 hours, 25 to 27 hours, and 64 to 67 hours. Embryo evaluation was performed according to the following parameters: fragmentation, nucleolar alignment, polar body apposition, blastomere number/morphology, and symmetry. The primary outcomemeasure was the mean GES score.We also compared fertilization, implantation, and pregnancy rates. Results Although the number of embryos transferred was greater in patients with endometriosis than in the control group (2.38 ± 0.66 versus 2.15 ± 0.54; p= 0.001), the meanGESwas similar inbothgroups (71 ± 19.8 versus 71.9 ± 23.5; p= 0.881). Likewise, the fertilization ratewas similar in all groups, being 61% in patients with endometriosis and 59% in the control group (p= 0.511). No significant differences were observed in the implantation (21% versus 22%; [p= 0.989]) and pregnancy rates (26.4% versus 28.4%; p= 0.989). Conclusion Embryo quality measured by the mean GES was not influenced by peritoneal endometriosis. Likewise, the evaluated reproductive outcomes were similar between infertile patients with and without endometriosis.


Resumo Objetivo Determinar a qualidade do embrião (média de escore embrionário graduado [EEG]) em pacientes inférteis com endometriose submetidas à fertilização in vitro com transferência de embrião (FIV-TE) em comparação com pacientes inférteis sem endometriose. Métodos Realizamos um estudo de caso-controle comparando 706 embriões (162 pacientes) divididos em dois grupos: 472 embriões derivados de pacientes sem endometriose (n = 109, pacientes inférteis com infertilidade tubária) e 234 embriões de pacientes do grupo de estudo (n= 53, inférteis pacientes com endometriose peritoneal). Todos os pacientes foram submetidos à fertilização in vitro usando um protocolo follicle-stimulating hormone (FSH) recombinante de estradiol-antagonista para estimulação ovariana. A média do EEGfoi realizada para avaliar todos osembriõesemtrêsmomentos: de 16 a 18 horas, 25 a 27 horas e 64 a 67 horas.A avaliaçãoembrionária foi realizada de acordo comos seguintes parâmetros: fragmentação, alinhamento nucleolar, aposição do corpo polar, número de blastômeros/morfologia e simetria. A medida de desfecho primário foi o escore médios embrionário (EEG). Também avaliamos como desfechos secundários as taxas de fertilização, implantação e gravidez. Resultados Embora o número de embriões transferidos tenha sido maior em pacientes com endometriose do que no grupo controle (2,38 ± 0,66 versus 2,15 ± 0,54; p = 0,001), o EEGmédio foi semelhante nos dois grupos (71 ± 19,8 versus 71,9 ± 23,5; p = 0,881). Da mesma forma, a taxa de fertilização foi semelhante em todos os grupos, sendo 61% nos pacientes com endometriose e 59% no grupo controle (p = 0,511). Não foram observadas diferenças significativas nas taxas de implantação (21% versus 22%; [p = 0,989]) e nas taxas de gravidez (26,4% versus 28,4%; p = 0,989). Conclusão A qualidade embrionária medida pelo EEGmédio não foi influenciada pela endometriose peritoneal. Da mesma forma, os resultados reprodutivos avaliados foram semelhantes entre pacientes inférteis com e sem endometriose.


Subject(s)
Humans , Female , Pregnancy , Adult , Embryo, Mammalian , Embryo Transfer , Endometriosis , Infertility, Female , Ovulation Induction , Pregnancy Outcome , Fertilization in Vitro , Case-Control Studies , Prospective Studies
13.
Protein & Cell ; (12): 7-28, 2021.
Article in English | WPRIM | ID: wpr-880895

ABSTRACT

Mammalian fertilization begins with the fusion of two specialized gametes, followed by major epigenetic remodeling leading to the formation of a totipotent embryo. During the development of the pre-implantation embryo, precise reprogramming progress is a prerequisite for avoiding developmental defects or embryonic lethality, but the underlying molecular mechanisms remain elusive. For the past few years, unprecedented breakthroughs have been made in mapping the regulatory network of dynamic epigenomes during mammalian early embryo development, taking advantage of multiple advances and innovations in low-input genome-wide chromatin analysis technologies. The aim of this review is to highlight the most recent progress in understanding the mechanisms of epigenetic remodeling during early embryogenesis in mammals, including DNA methylation, histone modifications, chromatin accessibility and 3D chromatin organization.


Subject(s)
Animals , Female , Male , Mice , Chromatin Assembly and Disassembly , DNA Methylation , DNA Transposable Elements , Embryo, Mammalian , Embryonic Development/genetics , Epigenesis, Genetic , Epigenome , Fertilization/physiology , Gene Expression Regulation, Developmental , Histone Code , Histones/metabolism , Oocytes/metabolism , Spermatozoa/metabolism
14.
Rev. bras. ciênc. vet ; 27(2): 88-92, abr./jun. 2020. il.
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1378302

ABSTRACT

O objetivo do estudo foi comparar o efeito das técnicas hormonais e de luz artificial nas éguas receptoras de embrião acíclicas avaliando as taxas de gestação aos 14 e 28 dias durante a fase de transição de primavera. Os 48 animais foram distribuídos aleatoriamente nos grupos: controle (CONT, n=16), éguas cíclicas na fase ovulatória; luz artificial (LUZ, n=16), éguas acíclicas submetidas ao tratamento de luz artificial; e hormônio (HORM, n= 16), éguas acíclicas submetidas ao protocolo hormonal na fase de transição. As éguas do grupo LUZ foram estimuladas por 60 dias com luz artificial durante cinco horas por dia. Nos grupos CONT e LUZ, quando observada a presença de folículo ≥ 35 mm de diâmetro e edema uterino ≥ grau II, foram administrados 1,5 mg de acetato de deslorelina e 1500 UI de hCG para induzir a ovulação. As éguas do grupo HORM foram tratadas com três doses de 1,5 mg de benzoato de estradiol e seguiram os mesmos protocolos dos Grupos CONT e LUZ. Foi avaliada a taxa de gestação por ultrassonografia aos 14 dias e confirmação aos 28 em todos os grupos experimentais. Foi realizada análise descritiva e teste Qui-quadrado (significância de 5%). Taxas de gestação aos 14 e 28 dias foram semelhantes (p>0,05) entre todos os grupos. Os tratamentos HORM e LUZ durante o período de transição inverno-primavera mostraram-se eficazes para atender ao programa de transferência de embrião. Por ser um método mais natural, o protocolo LUZ tem potencial como mais uma ferramenta biotecnológica na reprodução de equinos.


The aim of this study was to compare the effect of hormonal and artificial light techniques on acyclic embryo recipient mares by assessing pregnancy rates at 14 and 28 days during the spring transition period. The 48 animals were randomly assigned to the groups: control (CONT, n = 16), cyclic mares in the ovulatory phase; artificial light (LIGHT, n = 16), acyclic mares subjected to artificial light treatment; and hormone (HORM, n = 16), acyclic mares submitted to hormonal protocol in transition phase. In the LIGHT group, mares were stimulated with artificial light for five hours a day, for 60 days. In CONT and LIGHT groups, when a follicle ≥ 35 mm in diameter and uterine edema ≥ grade II were observed, 1.5 mg of deslorelin acetate and 1500 IU hCG were administered to induce ovulation. In the HORM group, mares were treated with three doses of 1.5 mg of estradiol benzoate and followed the same protocols as the CONT and LIGHT groups. Pregnancy rate was assessed by ultrasound at 14 days and confirmation at 28 days in all experimental groups. Descriptive analysis and chi-square test (5% significance) were performed. Pregnancy rates at 14 and 28 days were similar (p> 0.05) among all groups. The HORM and LIGHT treatments during the winter-spring transition period proved to be effective during the embryo transfer programs. As it is a more natural method, the LIGHT protocol has the potential to be one more biotechnological tool in equine reproduction.


Subject(s)
Animals , Ovulation/physiology , Pregnancy, Animal/physiology , Reproductive Techniques, Assisted/veterinary , Embryo, Mammalian , Embryo Transfer/veterinary , Fertility , Horses/embryology , Phototherapy/veterinary , Seasons , Anestrus
15.
Rev. bras. ciênc. vet ; 27(1): 34-39, jan./mar. 2020. il.
Article in English | LILACS, VETINDEX | ID: biblio-1379256

ABSTRACT

In the present study we aimed to test the best insemination dose for in vitro embryo production (IVEP) and to correlate sperm traits in bovine. In vitro matured oocytes were inseminated with three different sperm concentrations of the same bull: G1 (1*106), G2 (2*106) and G3 (4*106) sperm/mL. At 18 h post-insemination (hpi), presumptive zygotes [G1 (n=114), G2 (n=139) and G3 (n=136)] were stained to evaluate the pronuclei numbers, or continued to in vitro culture [G1 (n=102), G2 (n=111) and G3 (n=106)]. Sperm kinetics were analyzed using Computer-Assisted Semen Analysis (CASA). Sperm plasma membrane, acrosome integrity and mitochondrial activity were analyzed using fluorescent probes. In vitro fertilization (IVF) and IVEP data were compared using chi-square (P<0.05) and correlated with CASA and fluorescence data using Person Correlation (P<0.05). The IVF efficiency, cleavage and total blastocyst rates did not show any significant difference (P>0.05) among the groups. In G3, the polyspermy rate was the highest (7.4%; P<0.05) without difference (P>0.05) between G1 (0%) and G2 (0%). In G1, the early blastocyst rate was the highest (7.8%; P<0.05), without significant difference (P>0.05) between G2 (1.8%) and G3 (0.9%). The IVF efficiency and total blastocyst rates were positively correlated with curvilinear velocity (VCL) (r≃+1; P<0.05). We concluded that the reduction of insemination dose may negatively affect embryo development and VCL may be used as a parameter to improve the IVEP outcomes.


O objetivo deste estudo foi testar a melhor dose inseminante para a produção de embriões in vitro (IVEP) e sua correlação com as características espermáticas na espécie bovina. Oócitos maturados in vitro foram inseminados com três concentrações diferentes de espermatozoides de único touro: G1 (1*106), G2 (2*106) e G3 (4*106) espermatozoides/mL. Às 18h pós-inseminação (hpi), os presumíveis zigotos [G1 (114), G2 (139) e G3 (136)] foram corados para avaliar o número de pronúcleos, ou continuaram para o cultivo in vitro [G1 (102), G2 (111) e G3 (106)]. Os parâmetros da cinética espermática foram analisados usando o Computer-Assisted Semen Analysis (CASA). A integridade de membrana plasmática espermática, acrossomal e a atividade mitocondrial foram analisadas usando sondas fluorescentes. Os dados da fertilização in vitro (FIV) e IVEP foram comparadas com qui-quadrado (P=0,05) e correlacionados com dados de CASA e Fluorescência usando Correlação de Pearson (r=±1; P<0,05). A eficiência da FIV, taxas de clivagem e blastocisto total não mostraram diferença significativa (P>0,05) entre os grupos. Em G3, a taxa de polispermia foi a maior (7,4%; P<0,05), sem diferença (P>0,05) entre G1 (0%) e G2 (0%). Em G1, a taxa de blastocisto inicial foi a maior (7,8%; P<0,05), sem apresentar diferença significativa (P>0,05) com G2 (1,8%) e G3 (0,9%). A eficiência de FIV e a taxa de blastocisto total foram positivamente correlacionadas com velocidade curvilinear (VCL) (P<0,05). Concluímos que a dose inseminante reduzida pode negativamente afetar o desenvolvimento embrionário e VCL pode ser usada como parâmetro para melhorar os resultados da PEIV.


Subject(s)
Animals , Cattle , Blastocyst/cytology , Cattle/embryology , Insemination, Artificial/veterinary , Fertilization in Vitro/veterinary , Embryonic Development/genetics , Embryo, Mammalian/cytology , Semen Analysis/veterinary , Fertility
16.
Arq. bras. med. vet. zootec. (Online) ; 72(1): 33-39, Jan.-Feb. 2020. graf
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1088915

ABSTRACT

A biópsia embrionária associada à genotipagem permite a obtenção de informações genômicas antes mesmo da transferência dos embriões. Neste estudo, foram avaliadas amostras biopsiadas de blastocistos bovinos transferidos para receptoras (n=47), sob a hipótese de que a raça (Gir ou Girolando), o estádio embrionário (blastocisto ou blastocisto expandido) e a competência para estabelecimento de prenhez (positiva ou negativa) afetariam a quantidade e a qualidade do DNA da amostra obtida. O DNA foi extraído, amplificado, quantificado por eletroferograma e genotipado. O parâmetro call rate (CR) foi adotado para mensurar a qualidade da genotipagem. Obteve-se concentração de DNA de 86,07±171,66ng/µL e CR 0,73±0,17. O CR não variou em função da quantidade de DNA nas amostras. As variáveis raça e estádio embrionário não influenciaram a concentração de DNA, nem o CR. Houve efeito da prenhez sobre o CR (P=0,0187), mas, como houve maior CR nas amostras provenientes do grupo prenhez negativa, não foi possível associar esse parâmetro à qualidade embrionária. Concluiu-se que a raça e a qualidade embrionária não afetam os parâmetros aqui estudados em amostras embrionárias, ou seja, embriões com maiores chances de implantação não refletem alta qualidade nas amostras de biópsia genotipadas.(AU)


Embryo biopsy associated with genotyping allows genomic information before embryo transfer. In this study, blastocyst biopsy samples from embryos transferred to recipients (n= 47) were evaluated, under the hypothesis that breed (Gyr or Girolando), embryonic stage (blastocyst or expanded blastocyst) and competence to establish pregnancy (positive or negative) would affect the quantity and DNA quality of samples. DNA was extracted, amplified, quantified by electropherogram and genotyped. The parameter call rate (CR) was used to measure the quality of genotyping. DNA concentration of 86.07±171.66ng/µl, and CR 0.73±0.17 was obtained. CR did not vary according to the amount of DNA in the samples. The variables breed and embryonic stage had no influence on DNA concentration or CR. There was pregnancy effect on the CR (P= 0.0187), but since there was a higher CR in the samples from the negative pregnancy group, it was not possible to associate this parameter with the embryonic quality. We conclude that the breed and embryo quality do not affect the evaluated parameters in embryonic samples. Embryos with higher chances of implantation do not reflect high quality in embryo biopsy genotyped samples.(AU)


Subject(s)
Animals , Cattle , Selection, Genetic , Biopsy/veterinary , Sequence Analysis, DNA/veterinary , Embryo, Mammalian , Genotyping Techniques/veterinary , In Vitro Techniques/veterinary
17.
Braz. arch. biol. technol ; 63: e20200234, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132219

ABSTRACT

Abstract Curcumin (CUR) shows potential use for treating cancer. However, CUR has low solubility and reduced bioavailability, which limit its clinical effect. Therefore, the development of nanocarriers can overcome these problems and can ensure the desired pharmacological effect. In addition, it is mandatory to prove the quality, the efficacy, and the safety for a novel nanomedicine to be approved. In that sense, this paper aimed (a) to prepare CUR-loaded polyethylene glycol-poly(ε-caprolactone) nanocapsules; (b) to validate an analytical method by high performance liquid chromatography (HPLC) for quantifying CUR in these nanoformulations; (c) to evaluate the physicochemical stability of these formulations; and to investigate their cytotoxicity on NIH-3T3 mouse fibroblast cells. The HPLC method was specific to CUR in the loaded nanocapsules, linear (r = 0.9994) in a range of 10.0 to 90.0 µg.mL-1 with limits of detection and quantification of 0.160 and 0.480 µg.mL-1, respectively. Precision was demonstrated by a relative standard deviation lower than 5%. Suitable accuracy (102.37 ± 0.92%) was obtained. Values of pH, particle size, polydispersity index, and zeta potential presented no statistical difference (p > 0.05) for CUR-loaded nanoparticles. No cytotoxicity was observed against NIH-3T3 mouse embryo fibroblast cell line using both the tetrazolium salt and sulforhodamine B assays. In conclusion, a simple and inexpensive HPLC method was validated for the CUR quantification in the suspensions of nanocapsules. The obtained polymeric nanocapsules containing CUR showed suitable results for all the performed assays and can be further investigated as a feasible novel approach for cancer treatment.


Subject(s)
Animals , Mice , Curcumin/pharmacology , Embryonic Stem Cells/drug effects , Fibroblasts/drug effects , Chromatography, High Pressure Liquid , Toxicity Tests , Nanotechnology , NIH 3T3 Cells , Embryo, Mammalian/cytology , Nanocapsules
19.
Rev. bras. ginecol. obstet ; 41(9): 525-530, Sept. 2019. tab, graf
Article in English | LILACS | ID: biblio-1042339

ABSTRACT

Abstract Objective The etiology of embryonic demise is multifactorial, with chromosomal abnormalities being the most common (40%). The purpose of the present study is to evaluate the correlation between a serum biomarker, progesterone, and an ultrasonographic parameter, the distance between yolk sac and embryo (DYSE) in assessing the prognosis of pregnancy outcome in the 1st trimester. Methods The present study is a prospective case-control analysis that includes 2 groups of patients: 81 patients with first-trimester normal evolutive pregnancy and 89 patients with embryonic demise, all of the patients having between 6 and 11 weeks of amenorrhea. Endovaginal ultrasonographic exploration was performed to evaluate the distance between the lower pole of the embryo and the yolk sac. From each subject enrolled in the study, 20ml of blood was collected for progesterone serum level measurement. Results Regarding the DYSE in the case group, lower values were observed compared with the control group, the difference being statistically significant. In the statistical analysis of serum progesterone values, statistically significant differences were observed between the 2 groups (p<0.05). Conclusion The DYSE has a high positive predictive value in identifying pregnancies with potentially reserved outcome, with the present study demonstrating that a DYSE<3mm causes an unfavorable evolution of the pregnancy. Low serum levels of progesterone are associated with an increased rate of nonviable embryos. The correlation between these two parameters increases the effectiveness of screening methods in prenatal monitoring and improves the diagnostic methods for the firsttrimester pregnancies whose outcome potential can be reserved.


Subject(s)
Humans , Female , Pregnancy , Pregnancy Trimester, First/physiology , Pregnancy Trimester, First/blood , Progesterone/blood , Pregnancy Outcome/epidemiology , Ultrasonography, Prenatal , Prognosis , Yolk Sac/diagnostic imaging , Case-Control Studies , Embryo, Mammalian/diagnostic imaging
20.
Int. j. morphol ; 36(3): 1087-1094, Sept. 2018. graf
Article in English | LILACS | ID: biblio-954235

ABSTRACT

Catha edulis Forsk leaves (Khat) is a flowering plant. A high proportion of the adult population in the Arabian Peninsula and the Horn of Africa chews it for its mild stimulant effect. The aim of the current study was to investigate the embryotoxic and teratogenic effects of the Khat extract using 60 female pregnant rats. These were divided to a Khat extract-treated group and a control group. Methanolic extract of Khat was orally given to the treated group 4 days before mating and up to day 16 of pregnancy with a dose of 100 mg/kg. Our results showed that significant number of embryos of the Khat-treated mothers were malformed and different in size and shape compared to embryos from the mothers of the control group. At day 8 of pregnancy, malformed embryos had ill developed primitive layers. By day 10 of pregnancy, neural tube and the somite were not formed compared to the control embryos. At later stages of pregnancy, embryos of the Khat-treated mothers appeared severely abnormal with opened neural groove and visceral pouches. Disrupted normal neural tube development, undifferentiated brain vesicles, incomplete closure of the brain flexures were also observed in these embryos. Highly significant increase in the number of the resorbed embryos of the Khat-treated mothers were observed (P < 0.01). The resorbed embryos appeared as a cellular collection in their placenta with some of their decidua had no visible embryonic tissues. In conclusions, Khat induced embryotoxic effects as well as severely affected the early normal embryonic development in rat.


Catha edulis (Khat) es una planta floreciente. Una alta proporción de la población adulta en la Península Arábiga y el Cuerno de África la mastica por su efecto estimulante. El objetivo del presente estudio fue investigar los efectos embriotóxicos y teratogénicos del extracto de Khat utilizando 60 ratas hembras preñadas. Estas se dividieron en un grupo tratado con extracto de Khat y un grupo control. El extracto metanólico de Khat se administró por vía oral al grupo tratado 4 días antes del apareamiento y hasta el día 16 de preñez con una dosis de 100 mg / kg. Los resultados mostraron que una cantidad significativa de embriones de las madres tratadas con Khat tenían malformaciones y eran diferentes en tamaño y forma en comparación con los embriones de las madres del grupo control. En el día 8 de preñez, los embriones malformados tenían capas primitivas mal desarrolladas. Para el día 10 de preñez, el tubo neural y el somito no se formaron en comparación con los embriones del grupo control. En etapas posteriores de la preñez, los embriones de las madres tratadas con Khat parecían severamente anormales con surcos neurales abiertos y bolsas viscerales. También se observaron alteraciones en el desarrollo normal del tubo neural, vesículas cerebrales indiferenciadas y el cierre incompleto de las flexiones cerebrales en estos embriones. Se observó un aumento altamente significativo en el número de embriones reabsorbidos de las madres tratadas con Khat (P <0,01). Los embriones reabsorbidos aparecieron como una colección celular en su placenta con algunas de sus deciduas sin tejidos embrionarios visibles. Khat indujo efectos embriotóxicos y afectó severamente el desarrollo embrionario normal temprano en la rata.


Subject(s)
Animals , Female , Pregnancy , Rats , Plant Extracts/toxicity , Catha/chemistry , Embryo, Mammalian/drug effects , Teratogens , Rats, Sprague-Dawley
SELECTION OF CITATIONS
SEARCH DETAIL