RESUMO
In brief: Proper oocyte maturation is important in early embryo development. This study provides evidence that abnormal meiotic maturation can impact the developmental competency of preimplantation embryos. Abstract: This study aimed to investigate the potential role of the mouse SPECC1L (sperm antigen with calponin homology and coiled-coil domains 1 like), a microtubule and actin cytoskeleton-associated protein during oocyte meiotic maturation and its potential effects on preimplantation development. This study shows that the transcriptional levels of Specc1l did not significantly change from the germinal vesicle (GV) stage to the metaphase II (MII) stage, but maternal transcripts rapidly and gradually degraded after fertilization. SPECC1L was detected in both the cytoplasm and GV, but not in the nucleolus-like body in the GV intact oocyte. At the MII stages, SPECC1L was widely distributed in the cytoplasm but did not co-localize with chromatin. Knockdown of Specc1l expression in oocytes resulted in abnormal spindle morphology and misaligned chromosomes, as well as a decrease in the rate of polar body extrusion and a reduced developmental competence of oocytes, leading to decreased blastocyst formation rate. In conclusion, this study provides evidence that SPECC1L plays a critical role in mouse oocyte meiotic maturation and early embryo development, specifically in proper bipolar spindle assembly and extrusion of the first polar body.
RESUMO
Meat tenderness is considered the most important trait contributing to beef quality, level of consumer satisfaction, willingness to pay premium prices and industry profit. Genomic selection method would be helpful for genetic improvement of traits with low heritability and that are difficult to measure. The identification of core genes can aid genomic selection for complex traits with low heritability that are difficult to measure. We performed statistical analysis of associations between longissimus dorsi muscle tenderness and gene expression in 20 Hanwoo cattle, using Warner-Bratzler shear force and RNAseq data, respectively. We found a total of 166 core genes, from which six (ASAP1, CAPN5, ELN, SUMF2, TTC8 and MGAT4A) were regulated by 16 cis-expression quantitative trait loci (eQTL) SNPs. Notably, we found that a cis-eQTL SNP of the ELN gene contained an MFZ-1 binding site in its putative promoter region. These findings provide useful information for genomic prediction of beef tenderness in Hanwoo cattle.
Assuntos
Carne , Locos de Características Quantitativas , Bovinos/genética , Animais , Carne/análise , Fenótipo , Biomarcadores , República da Coreia , Músculo Esquelético/fisiologiaRESUMO
Cytoplasmic polyadenylation element-binding protein 2 (CPEB2) is an mRNA-binding protein that regulates the cytoplasmic polyadenylation of mRNA and is required for tight junction (TJ) assembly in the trophectoderm epithelium during porcine preimplantation development. However, the regulatory mechanism underlying TJ assembly by CPEB2 has not been examined. The aim of this study was to elucidate how Cpeb2 regulates the subcellular localisation and stabilisation of Tjp1 mRNA for TJ biogenesis during mouse preimplantation. CPEB2 was detected in nuclei during the early stages of development and was localised at apical cell membranes from the morula stage onwards. In the Cpeb2 knockdown (KD), we observed reduced blastocyst formation with impaired TJs, defective inner cell mass development in the blastocyst outgrowth assay, and loss of pregnancy after embryo transfer. More importantly, Tjp1 mRNA was localised apically in the outer cells of control morulae but not in the Cpeb2 KD embryos, indicating that CPEB2 mediated the translocalisation of Tjp1 mRNA from the nuclei. Finally, in the control embryos, the length of the Tjp1 mRNA poly (A) tail was varied, while only a single peak was detected in the Cpeb2 KD embryos. These findings suggest that the binding of CPEB2 to the cytoplasmic polyadenylation element in the 3'-UTR can confer stability on Tjp1 mRNA and translational regulation. In summary, we demonstrated for the first time that CPEB2 mediates Tjp1 mRNA stabilisation and subcellular localisation for TJ assembly during mouse blastocyst formation.
Assuntos
Blastocisto , Junções Íntimas , Animais , Desenvolvimento Embrionário , Camundongos , Mórula/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Suínos , Junções Íntimas/metabolismo , Proteína da Zônula de Oclusão-1/metabolismoRESUMO
Genome-wide association studies (GWAS) have accelerated the identification of functional trait loci in cattle and identified single nucleotide polymorphisms (SNPs) in candidate genes associated with fertility and production traits in high milk yield dairy cattle. The fertility of Hanwoo (Korean native beef cattle) has declined after the adaptation of a selection program for high quantity and quality meat. However, there are few GWAS studies of fertility in beef cattle. We performed a genome-wide association study of 40 Korean native beef cattle heifers with imputed 770 K genotype and identified 12 significant SNPs within seven regions on three chromosomes (BTA 8, BTA 16 and BTA 24) associated with services per conception (SPC). Five SNPs were located in the ABCA1, BRINP3 and ESRRG genes, which are involved in early embryo development. In addition, 27 proximal genes were identified within 1 Mb of the candidate SNPs, which are involved in muscle cell differentiation and muscle structure development. However, we did not find any previously reported SNPs related to fertility in Holstein cows. Taken together, we identified SNPs associated with SPC and their proximal genes using gene-based analysis and the candidates were different from SNPs associated with subfertility of dairy cattle.
Assuntos
Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , Animais , Bovinos/genética , Feminino , Fertilidade/genética , Estudo de Associação Genômica Ampla/veterinária , Genótipo , Polimorfismo de Nucleotídeo Único/genética , República da CoreiaRESUMO
A synthetic progestin altrenogest (ALT) is used to synchronize the estrus cycle of swine for fixed-time artificial insemination (AI) and has been shown to improve follicular development and reproductive performances in post-weaning sows. However, the effects of ALT treatment on reproductive tracts, including the ovaries, oviducts and uterus have not been yet clarified. In this study, we examined the expression of genes involved in endometrial responses in ALT-treated sows. ALT did not significantly alter luteinizing hormone (LH), follicle-stimulating hormone (FSH) and estradiol profiles in blood compared to untreated control. Quantitative RT-polymerase chain reaction (qRT-PCR) analysis showed that the expression of genes encoding galectin-3 (LGALS3) and fibroblast growth factor 9 (FGF9) was upregulated in the reproductive tracts of ALT-treated sows, including the ovaries, oviducts and uteri. Moreover, ALT treatment induced the expression of FGF9 and galectin-3 proteins, and promoted their localization to the luminal epithelium of the oviducts and uterus. Our findings suggest that the enhancement of reproductive performance shown by ALT-treated sows is associated with the upregulation of galectin-3 and FGF9, which are essential for endometrial receptivity, successful implantation, and pregnancy.
Assuntos
Fator 9 de Crescimento de Fibroblastos , Galectina 3 , Suínos/genética , Acetato de Trembolona , Animais , Feminino , Fator 9 de Crescimento de Fibroblastos/metabolismo , Hormônio Foliculoestimulante , Galectina 3/metabolismo , Inseminação Artificial/veterinária , Ovário/efeitos dos fármacos , Ovário/metabolismo , Oviductos/efeitos dos fármacos , Oviductos/metabolismo , Gravidez , Acetato de Trembolona/análogos & derivados , Acetato de Trembolona/farmacologia , Útero/efeitos dos fármacos , Útero/metabolismoRESUMO
In mammals, the early embryo travels down the oviduct to the uterus and prepares for implantation. The unique features of preimplantation development include compaction followed by blastocyst formation. This first cell lineage specification involves various proteins including cell polarity regulators, kinases, and transcription factors. In this study, a novel gene named predicted gene 11545 (Gm11545) expressed predominantly in mouse early embryos was identified and characterized at the transcript, protein, cellular, and functional levels. The Gm11545 protein localized to both cytoplasmic and membrane regions of preimplantation embryos. Remarkably, knockdown of Gm11545 led to arrest of mouse embryos at the morula stage and consequent impairment of blastocyst formation. Expression patterns of the key transcription factors critical for early lineage specification, octamer-binding transcription factor 4 and caudal type homeobox 2, were affected by Gm11545 depletion. Based on the collective findings, we propose that the novel protein identified in this study, Gm11545, is implicated in cell proliferation and cell lineage specification critical for blastocyst formation.-Kim, J., Kim, J., Jeong, J., Hong, S. H., Kim, D., Choi, S., Choi, I., Oh, J. S., Cho, C. Identification of a novel embryo-prevalent gene, Gm11545, involved in preimplantation embryogenesis in mice.
Assuntos
Blastocisto/fisiologia , Implantação do Embrião/genética , Embrião de Mamíferos/fisiologia , Desenvolvimento Embrionário/genética , Fatores de Transcrição/genética , Animais , Linhagem da Célula/genética , Polaridade Celular/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Masculino , CamundongosRESUMO
Understanding preimplantation embryo development has important implications for assisted reproductive technologies (ARTs) after the introduction of in vitro fertilisation and embryo transfer because most embryonic losses occur during pre/peri-implantation. Recent studies have shown that tight junctions (TJs) are important components for embryos to develop to the blastocyst stage. However, their biological function after cavitation has not been extensively studied. We examined TJ assembly focusing on coxsackievirus and adenovirus receptor (Cxadr) and A disintegrin and metalloproteinase 10 (Adam10) using siRNA and/or an Adam10-specific inhibitor (GI254023X). TJ-associated genes, including occludin and tight junction protein 1 (Tjp1), were downregulated in the Cxadr knockdown (KD) embryos but were unaltered in Adam10 KD embryos. However, Adam10 KD or chemical inhibition affected subcellular localisation of Adam10, Cxadr, and Tjp1, leading to disrupted TJ assembly. Furthermore, Cxadr KD or GI254023X-treated blastocysts showed a relatively smaller outgrowth area and aberrant expression of transcription factor AP-2γ, a trophoblast-specific marker in the in vitro embryo outgrowth assay. In summary, we demonstrated that the Cxadr-Adam10 complex might moderate TJ integrity/stability and play pivotal roles during early embryonic development. Collectively, understanding the establishment of the TJ complex and its integrity will provide insight into translational research for predicting and selecting developmental competency for ART.
Assuntos
Proteína ADAM10/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/metabolismo , Proteínas de Membrana/metabolismo , Complexos Multiproteicos/metabolismo , Junções Íntimas/metabolismo , Trofoblastos/metabolismo , Proteína ADAM10/genética , Secretases da Proteína Precursora do Amiloide/genética , Animais , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/genética , Regulação para Baixo , Proteínas de Membrana/genética , Camundongos , Complexos Multiproteicos/genética , RNA Interferente Pequeno/genética , Junções Íntimas/genética , Fator de Transcrição AP-2/genética , Fator de Transcrição AP-2/metabolismo , Trofoblastos/citologia , Proteína da Zônula de Oclusão-1/biossíntese , Proteína da Zônula de Oclusão-1/genéticaRESUMO
The evolution of surface cleanliness and the electronic properties-Dirac voltage(V Dirac), hysteresis and mobility (µ) of a graphene field-effect transistor (GFET)-were monitored by measuring lateral force microscopy and drain current (I D) as a function of gate voltage (V G), after mechanically cleaning the surface, scan-by-scan, with contact-mode atomic force microscopy. Both the surface cleanliness and the electronic properties evolved, showing a sudden improvement and then saturation for a mobility of around 2200 cm2 V-1 s-1. We found that the mobility suppression of the as-fabricated GFET deviated from a randomly distributed impurities model, which predicted a greater mobility than obtained from the measured V Dirac. Therefore, the substrate impurities are excluded from the origins of the extraordinary suppression of the mobility, and the possible origin will be discussed.
RESUMO
Cytoplasmic polyadenylation element binding protein (CPEB) is an RNA-binding protein that promotes elongation of poly(A) tails and regulates mRNA translation. CPEB depletion in mammary epithelium is known to disrupt tight-junction (TJ) assembly via mislocalisation of tight junction protein 1 (TJP1), but the role of CPEB in the biological functions associated with TJs has not yet been studied. The objective of this study was to investigate the roles of CPEB2 during porcine parthenote development. CPEB2 was detected in both the nuclei and apical cytoplasm at the 4- and 8-cell stages and was localised to cell-cell contact after the initiation of the morula stage. Its depletion led to retarded blastocyst formation caused by impaired TJ assembly. Moreover, transcription of TJ-associated genes, including TJP1, Coxsackie virus and adenovirus receptor (CXADR) and occludin (OCLN), was not affected, but the corresponding proteins were not properly localised at the apical cell membrane in morulae, suggesting that CPEB2 confers mRNA stability or determines subcellular localisation for translation. Remarkably reduced relative levels of TJP1 transcripts bearing the 3'-untranslated region were noted, indicating that CPEB2 mediates TJP1 mRNA stability. In conclusion, our findings demonstrate that because of its regulation of TJP1, CPEB2 is required for TJ assembly during porcine blastocyst development.
RESUMO
Cytoplasmic polyadenylation element binding protein (CPEB) is an RNA-binding protein that promotes elongation of poly(A) tails and regulates mRNA translation. CPEB depletion in mammary epithelium is known to disrupt tight-junction (TJ) assembly via mislocalisation of tight junction protein 1 (TJP1), but the role of CPEB in the biological functions associated with TJs has not yet been studied. The objective of this study was to investigate the roles of CPEB2 during porcine parthenote development. CPEB2 was detected in both the nuclei and apical cytoplasm at the 4- and 8-cell stages and was localised to cell-cell contact after the initiation of the morula stage. Its depletion led to retarded blastocyst formation caused by impaired TJ assembly. Moreover, transcription of TJ-associated genes, including TJP1, Coxsackie virus and adenovirus receptor (CXADR) and occludin (OCLN), was not affected, but the corresponding proteins were not properly localised at the apical cell membrane in morulae, suggesting that CPEB2 confers mRNA stability or determines subcellular localisation for translation. Remarkably reduced relative levels of TJP1 transcripts bearing the 3'-untranslated region were noted, indicating that CPEB2 mediates TJP1 mRNA stability. In conclusion, our findings demonstrate that because of its regulation of TJP1, CPEB2 is required for TJ assembly during porcine blastocyst development.
Assuntos
Blastocisto/metabolismo , Desenvolvimento Embrionário/fisiologia , Oócitos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Junções Íntimas/metabolismo , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Maturação in Vitro de Oócitos , Ocludina/metabolismo , Poliadenilação , Proteínas de Ligação a RNA/genética , Suínos , Proteína da Zônula de Oclusão-1/metabolismoRESUMO
Coxsackie virus and adenovirus receptor (CXADR) is a member of the immunoglobulin superfamily as well as a member of the junctional adhesion molecule family of adhesion receptor. In human pre-implantation embryos, CXADR was detected and co-localized with tight junction (TJ) proteins on the membrane of the trophectoderm. However, its physiological roles were not elucidated in terms of blastocyst formation. Here, we reported expression patterns and biological functions of CXADR in porcine pre-implantation embryos. The transcripts of CXADR were detected at all stages of pre-implantation. Particularly, its expression dramatically increased and preferentially localized at the edge of cell-cell contacts, rather than in the nucleus from the eight-cell stage onwards. CXADR expression was knocked down (KD) by microinjecting double-stranded RNA into one-cell parthenotes. The vast majority of CXADR KD embryos failed to develop to the blastocyst stage, and a few developed KD blastocysts did not expand fully. Analysis of adherens junction (AJ)- and TJ-associated genes/proteins using qRT-PCR, immunocytochemistry and assessment of TJ permeability using FITC-dextran uptake assay revealed that the developmental failure and relatively small cavities are attributed to the defects of TJ assembly. In summary, CXADR is necessary for the AJ and TJ assembly/biogenesis during pre-implantation development.
Assuntos
Junções Aderentes/metabolismo , Blastocisto/citologia , Blastocisto/metabolismo , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Junções Íntimas/metabolismo , Animais , Western Blotting , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/genética , Humanos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SuínosRESUMO
The trophectoderm epithelium is the first differentiated cell layer to arise during mammalian development. Blastocyst formation requires the proper expression and localization of tight junction, polarity, ion gradient and H2O channel proteins in the outer cell membranes. However, the underlying transcriptional mechanisms that control their expression are largely unknown. Here, we report that transcription factor AP-2γ (Tcfap2c) is a core regulator of blastocyst formation in mice. Bioinformatics, chromatin immunoprecipitation and transcriptional analysis revealed that Tcfap2c binds and regulates a diverse group of genes expressed during blastocyst formation. RNA interference experiments demonstrated that Tcfap2c regulates genes important for tight junctions, cell polarity and fluid accumulation. Functional and ultrastructural studies revealed that Tcfap2c is necessary for tight junction assembly and paracellular sealing in trophectoderm epithelium. Aggregation of control eight-cell embryos with Tcfap2c knockdown embryos rescued blastocyst formation via direct contribution to the trophectoderm epithelium. Finally, we found that Tcfap2c promotes cellular proliferation via direct repression of p21 transcription during the morula-to-blastocyst transition. We propose a model in which Tcfap2c acts in a hierarchy to facilitate blastocyst formation through transcriptional regulation of core genes involved in tight junction assembly, fluid accumulation and cellular proliferation.
Assuntos
Desenvolvimento Embrionário/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Junções Íntimas/metabolismo , Fator de Transcrição AP-2/metabolismo , Animais , Blastocisto/metabolismo , Técnicas de Cultura de Células , Diferenciação Celular , Polaridade Celular , Proliferação de Células , Imunoprecipitação da Cromatina , Biologia Computacional , Células-Tronco Embrionárias/citologia , Feminino , Íons , Masculino , Camundongos , Microscopia Eletrônica de Transmissão , Interferência de RNA , Fator de Transcrição AP-2/genética , Transcrição GênicaRESUMO
To investigate effects of heat stress on developmental competence, in-vitro fertilized zygotes were incubated at different temperatures until 96 h post human chorionic gonadotrophin (HCG). Under severe and moderate conditions (41°C and 40°C), most embryos did not overcome the 2-cell block. In long-term mild heat stress (39°C until 96 h post HCG), cleavage and blastocyst formation were comparable to non-heat-stress control, but the number of live pups per transferred embryo and mean litter size were significantly affected (P < 0.05) in the mild-heat-stress group (19.4%, and 5.1 ± 0.4, respectively), compared with control (41.7% and 8.3 ± 0.3, respectively). To elucidate the different competence, gene expression was examined and the numbers of inner cell mass (ICM) and trophectoderm (TE) cells were counted. Aberrant expression of genes for embryonic viability and trophoblast differentiation in the mild-heat-stressed blastocysts was found. Moreover, the expanded blastocysts in the heat-stressed group and the control had a ICM:TE ratio of 1:2.47 and 1:2.96 with average total cell numbers of 59.21 ± 2.38 and 72.79 ± 2.40, respectively (P < 0.05), indicating lower cell numbers in TE. These findings underscore that prevention of heat stress in early embryos is important for maintaining embryo viability embryos during pregnancy.
Assuntos
Desenvolvimento Embrionário , Resposta ao Choque Térmico , Animais , Implantação do Embrião , Camundongos , RNA Mensageiro/genéticaRESUMO
Transcription factor AP-2? (TFAP2C) is a member of the transcription factor activating enhancer binding protein (AP) family. In the present study we determined the temporal and spatial expression patterns of TFAP2C in porcine parthenotes during preimplantation development. Porcine TFAP2C transcripts were expressed at all stages of preimplantation development, with highest expression at the 8-cell stage. In contrast with the mouse, TFAP2C protein was not restricted to the trophectoderm and was also detected in the ICM in blastocyst stage porcine parthenotes. In knockdown (KD) experiments, most TFAP2C-depleted embryos were arrested before the compacted 8-cell stage. This developmental failure is attributed to abnormal expression of genes involved in cell adhesion, tight junction biogenesis and cell proliferation. Interestingly, although the conserved region 4 (CR4) of the porcine OCT4 5? upstream regionlacked the AP2C-binding motif, OCT4 transcript levels were elevated in porcine TFAP2C-KD 8-cell embryos, suggesting TFAP2C may be involved in the regulation of OCT4 in porcine embryos through other mechanisms. In summary, the results suggest that TFAP2C is necessary for the transition from de novo transcript synthesis by activation to compaction and further development, and the different expression patterns of TFAP2C in porcine embryos may reflect species-specific functions during preimplantation embryo development.
RESUMO
Subclinical ketosis (SCK) is a prevalent metabolic disorder that occurs during the transition to lactation period. It is defined as a high blood concentration of ketone bodies (beta-hydroxybutyric acid f ≥ 1.2 mmol/L) within the first few weeks of lactation, and often presents without clinical signs. SCK is mainly caused by negative energy balance (NEB). The objective of this study is to identify single nucleotide polymorphisms (SNPs) associated with SCK using genome-wide association studies (GWAS), and to predict the biological functions of proximal genes using gene-set enrichment analysis (GSEA). Blood samples were collected from 112 Holstein cows between 5 and 18 days postpartum to determine the incidence of SCK. Genomic DNA extracted from both SCK and healthy cows was examined using the Illumina Bovine SNP50K BeadChip for genotyping. GWAS revealed 194 putative SNPs and 163 genes associated with those SNPs. Additionally, GSEA showed that the genes retrieved by Database for Annotation, Visualization, and Integrated Discovery (DAVID) belonged to calcium signaling, starch and sucrose, immune network, and metabolic pathways. Furthermore, the proximal genes were found to be related to germ cell and early embryo development. In summary, this study proposes several feasible SNPs and genes associated with SCK through GWAS and GSEA. These candidates can be utilized in selective breeding programs to reduce the genetic risk for SCK and subfertility in high-performance dairy cows.
RESUMO
Early diagnosis of pregnancy is directly related to cost-effective livestock production. We produced a rat monoclonal antibody (mAb) against synthesized porcine early pregnancy factor (pEPF) using conventional hybridoma technology and used it as a tool for the detection of early pregnancy in Duroc sows. The rat pEPF-mAb showed reactivity to uterine tissues of pregnant sows 20 or 30 days post-mating (day 0 defined as the day of mating) and non-pregnant sows (confirmed signs of estrus) in western blotting. Immunohistochemical analysis confirmed that pEPF was located in the stromal and grand epithelial tissues of pregnant sows 20 or 30 days post-mating. In the enzyme-linked immunosorbent assay, pEPF expression in urine and blood showed similar results, with the highest expression observed in pregnant sows 20 days post-mating, whereas there was no significant difference in expression levels between non-pregnant sows and pregnant sows 30 days post-mating. The pEPF-mAb-based pregnancy diagnostic kit can be applied to pig urine samples non-invasively collected at 20 days post-mating with 70 % accuracy. Further improvements to the kit's diagnostic performance may lead to substantial benefits for the swine industry, facilitating more efficient and accurate reproductive management.
RESUMO
The bovine embryo production industry has seen significant growth over the past two decades, particularly in the production of in vitro produced embryos. This growth, driven by advancements in cryopreservation, in vitro culture mediums, ovum pick-up (OPU) procedures, ultrasonography devices, and embryo transfer (ET) has been notable. Particularly, ET is crucial for disseminating high genetic merit and amplifying foreign breeds by importing frozen embryos. This retrospective study aimed to assess factors affecting conception per embryo transfer (CPET) in Holstein-Friesian cattle in South Korea from October 2008 to July 2022. We evaluated type of embryo breed, type of embryo production (fresh and frozen; in vitro and in vivo production), recipient conditions including estrus type, corpus luteum quality, parity (nulliparous heifers, primiparous, and multiparous cows), and the daily mean temperature-humidity index (THI) as an index for heat stress. Type of embryo breed and estrus had no significant impact on CPET. However, we observed higher CPET in recipients with good quality corpus luteum, nulliparous heifers, and surrogates receiving fresh in vitro and frozen in vivo embryos. Importantly, CPET was not adversely affected by mild heat stress conditions (up to daily mean THI 76), indicating that using frozen in vivo embryos produced by multiple ovulation embryo transfer and fresh in vitro embryos by OPU-ET can help alleviate the subfertility issues in dairy cattle caused by global warming in Korea.
Assuntos
Transferência Embrionária , Animais , Bovinos/fisiologia , Transferência Embrionária/veterinária , Transferência Embrionária/métodos , Estudos Retrospectivos , República da Coreia , Feminino , Gravidez , Criopreservação/veterinária , Fertilização , Fertilização in vitro/veterináriaRESUMO
The cryopreservation of immature oocytes at the germinal vesicle (GV) stage would create an easily accessible, non-seasonal source of female gametes for research and reproduction. The present study investigated the ability of ovine oocytes vitrified at the GV stage using a cryoloop to be subsequently matured, fertilised and cultured in vitro to blastocyst-stage embryos. Selected cumulus-oocyte complexes obtained from mature ewes at the time of death were randomly divided into vitrified, toxicity and control groups. Following vitrification and warming, viable oocytes were matured in vitro for 24 h. Matured oocytes were either evaluated for nuclear maturation, spindle and chromosome configuration or fertilised and cultured in vitro for 7 days. No significant differences were observed in the frequencies of IVM (oocytes at the MII stage), oocytes with normal spindle and chromatin configuration and fertilised oocytes among the three groups. Cleavage at 24 and 48 h post insemination was significantly decreased (P<0.01) in vitrified oocytes. No significant differences were observed in the proportion of blastocyst development between vitrified and control groups (29.4% v. 45.1%, respectively). No significant differences were observed in total cell numbers, the number of apoptotic nuclei or the proportion of diploid embryos among the three groups. In conclusion, we report for the first time that ovine oocytes vitrified at the GV stage using a cryoloop have the ability to be matured, fertilised and subsequently developed in vitro to produce good-quality blastocyst embryos at frequencies comparable to those obtained using fresh oocytes.
Assuntos
Blastocisto/citologia , Criopreservação/veterinária , Ectogênese , Fertilização in vitro/veterinária , Oócitos/citologia , Carneiro Doméstico/fisiologia , Vitrificação , Animais , Apoptose , Blastocisto/metabolismo , Núcleo Celular/metabolismo , Sobrevivência Celular , Fase de Clivagem do Zigoto/citologia , Fase de Clivagem do Zigoto/metabolismo , Criopreservação/instrumentação , Células do Cúmulo/fisiologia , Técnicas de Cultura Embrionária/veterinária , Feminino , Técnicas de Maturação in Vitro de Oócitos/veterinária , Masculino , Oócitos/metabolismo , Oogênese , Preservação do Sêmen/veterinária , Fuso Acromático/metabolismoRESUMO
Summary Poor embryo quality is a major problem that contributes to the failure of pregnancy in somatic cell nuclear transfer (SCNT). The aims of this study were to improve the quality of ovine SCNT embryos by modifying the conventional activation protocol with the addition of SrCl2. In order to achieve this objective we conducted a series of experiments with in vitro-matured oocytes to optimize conditions for oocyte activation with strontium, and subsequently applied the protocol to SCNT embryos. The results showed that in vitro-matured oocytes could be activated effectively by 10 mM SrCl2 + 5 mg/ml cytochalasin B (CB) for 5 h in the absence of Ca2+ and that the blastocyst rate on day 7 (33.2%) was similar to that in the control group (31.0%) (5 M calcium ionophore [IP] A23187 for 5 min and cultured in CB/cycloheximide [CHX] for 5 h; P > 0.05). In SCNT experiments, the total cell number/blastocyst (104.12 ± 6.86) in the IP + SrCl2/CB-treatment group was, however, significantly higher than that in the control group (81.07 ± 3.39; P < 0.05). Apoptotic index (12.29 ± 1.22%) was significantly lower than the control (17.60 ± 1.39%; P < 0.05) when a combination of IP and SrCl2/CB was applied to SCNT embryos. In addition, karyotyping of the SCNT embryos showed that the percentage of diploid blastocysts in the IP + SrCl2/CB-treatment group was slightly higher than that in the control (P > 0.05). We conclude that the modified activation protocol with IP + SrCl2/CB can improve significantly the quality of ovine SCNT embryos in terms of total cell number, apoptosis and ploidy.
Assuntos
Blastocisto/efeitos dos fármacos , Ionóforos de Cálcio/farmacologia , Embrião de Mamíferos/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Técnicas de Transferência Nuclear , Oócitos/efeitos dos fármacos , Estrôncio/farmacologia , Animais , Apoptose/efeitos dos fármacos , Blastocisto/citologia , Cálcio/metabolismo , Sinergismo Farmacológico , Embrião de Mamíferos/citologia , Feminino , Oócitos/citologia , Partenogênese/efeitos dos fármacos , Gravidez , Prenhez , OvinosRESUMO
Intracranial hemorrhage (ICH) is a type of stroke with a high mortality rate and failing to localize even minor ICH can put a patient's life at risk. However, its patterns are diverse in shapes and sizes and, sometimes, even hard to recognize its existence. Therefore, it is challenging to accurately detect and localize diverse ICH patterns. In this article, we propose a novel Perihematomal Edema Guided Scale Adaptive R-CNN (PESA R-CNN) for accurate segmentation of various size hemorrhages with the goal of minimizing missed hemorrhage regions. In our approach, we design a Center Surround Difference U-Net (CSD U-Net) to incorporate Perihematomal Edema (PHE) for more accurate Region of Interest (RoI) generation. We trained CSD U-Net to predict PHE and hemorrhage regions as targets in a weakly supervised manner and utilized its prediction results to generate RoI. By including more informative features of PHE around hemorrhage, this enhanced RoI generation allows a model to reduce the false-negative rate. Furthermore, these expanded RoIs are aligned with the Scale Adaptive RoI Align (SARA) module based on their size to prevent the loss of fine-scale information and small hemorrhage patterns. Each scale adaptively aligned RoI is processed with the corresponding separate segmentation network of Multi-Scale Segmentation Network (MSSN), which integrates the results from each scale's segmentation network. In experiments, our model shows significant improvement on dice coefficient (0.697) and Hausdorff distance (12.918), compared to all other segmentation models. It also minimizes the number of missing small hemorrhage regions and enhances overall segmentation performance on diverse ICH patterns.